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Getting Started Using ZEMAX

1. Wavelength Data Use Wavelength um Weight mai oseei327 0 amp 8 of M2 osses fi m3 loee75 8 8ft Da bs jfi Os fs fi De fs j fi 0 55 a Page 28 of 74 In the drop down list next to the Select button choose the spectrum F d C visible and press the Select button to copy this spectrum into the Wavelength Data dialog This sets three wavelengths in ascending order and sets wavelength 2 as the primary wavelength Note In real life any time you find yourself making assumptions about what specifications mean always refer back to the customer Part of your QA process should be to do a point by point comparison of each specified parameter how it has been entered into ZEMAX and how it will be tested in the built system Last we will define the field of view which is 10 full field of view hence 5 half field Click on the Fie button or click on System Field and enter Field Data Type Angle Deg Object Height e Field Normalization Radial Use X Field Y Hield Weight VDX vif p o pg v2 E 1 0000 foomo j Dag o 0 0000 0 00000 Note As the lens is rotationally symmetric we do not need to specify a field point at y 5 or at x 5 or 5 Always define your field points in y only unless you specifically require a non rotationally symmetric lens system We have now entered everything we need about the light coming into the lens its
2. 2 1 The Address Tab This is shown above and it allows you to enter information about your organization which is then printed on most graphics windows 2 2 The Folders Tab This tab defines the folders that ZEMAX will use for the various file types it needs They can be redirected wherever you wish by pressing the button for any path and navigating to the desired location 2 7 3 The Editors Tab This tab allows you to adjust the appearance of the various Editors that ZEMAX uses Adjusting the Decimals setting affects how many decimal places ZEMAX displays in the Editor cells but does not affect the accuracy of the data itself All data is stored in ZEMAX as double precision floating point numbers Selecting Compact will vary the number of decimals displayed to minimize the space required to display numbers so Page 6 of 74 that trailing decimals are not displayed unless necessary You can change the font font size and cell widths of all the editors Page 7 of 74 3 The ZEMAX User Interface Start ZEMAX and open the sample file Samples Sequential Objectives Double Gauss 29 degree field Even if you intend to use only the non sequential mode of ZEMAX you should still follow this example as the user interface is common to both sequential and non sequential ray tracing The user interface consists of three main elements 1 The program frame that consists of the menu strip and toolbar at the top and a status ba
3. 4 u a H u fa P 4 oJ m H a 4 i 36 45 5 E Incident Angle In Degrees Reflection vs Angle Coating AR on Surface 1 Incident media Air Substrate SK Wavelength 0 5876 Double Gauss 24 degree field zm Configuration 1 of 1 Other plots in the same menu let you see transmission diattenuation phase retardance etc In the coating column of surface 1 press the spacebar to delete the coating and note how the reflection vs angle plot changes Coating names can be typed directly into the coating column to apply the coating to the surface 6 2 2 Adding Coatings to Non Sequential Objects It is only a little more complex to add coatings to non sequential objects Because objects are volumes and not surfaces one object may have several faces that can take different coatings Open the sample file Non sequential Ray splitting Beam Splitter zmx Page 66 of 74 A En i El i H h LOL Update Settings Print Window Text Zoom Beam splitter using coatings Contiquration 1 of 1 Double click on the second prism object object 3 to open its properties and go to the Coat Scatter tab This object has two faces face 1 which is the splitter face the hypotenuse of the prism and face 0 is everything else Face 1 is coated with an IDEAL coating 1 5 which transmits 50 and reflects 50 of the ray energy and face 0 is coated with 1 95 which transmits 95 and reflects 5 of energy Diffraction Sources Draw
4. Apodization Factor C Telecentric Object Space Afocal Image Space tterate Solves When Updating In this case we define the Entrance Pupil Diameter to be 33 33 lens units Click on the Units tab to see that millimeters are the defined lens units in this file Other options are Page 11 of 74 meters centimeters and inches Once the lens 50 units are defined any length where the units Update Settings Print Window Text Zoom are not explicitly given is in lens units Entrance Pupil Diameter EPD defines the size of the on axis bundle of light entering the lens system In the double Gauss sample file we are using which is a traditional SLR type camera lens ZEMAX traces rays at this height through the lens and computes the size of the aperture stop surface marked as STO in the Lens Data Editor drawn in red opposite The aperture stop surface is usually a ring diaphragm so in reality the radial size of this surface defines the EPD not the other way around lf you prefer this alternative definition then choose the Aperture Type in the General dialog box to be Float by Stop and then change the semi diameter of the STO surface to say 8 mm Double click all the open Analysis windows to make them update to reflect this change and notice the change in the lens apertures and performance ZEMAX automatically computes the appropriate size of each surface so that all light passes through each surfa
5. Points M Use Polarization Aberrations IV Apply Fixed Apertures 4 Use Relative Illumination Detector and Display Settings Simulated Image Pixel Size Chief Ray X Pooels Y Pixels This will produce a simulation of what a real source scene described by an input bitmap will look like when imaged by the lens This analysis is amazingly fast taking literally only a few seconds to produce the image below This feature is ideal for communicating real world optical performance to non optical specialists OUL 2 Image Simulation Update Settings Print Window Text Zoom Page 39 of 74 4 8 Glass Optimization There is an important difference between optimizing glasses and other system parameters Parameters like radii of curvature thicknesses etc can be smoothly varied a thickness of 10 0 mm can become 10 00001mm for example However glasses are only available with discrete properties you cannot simply perturb a glass to get a slightly different refractive index Instead we use a method called Glass Substitution to swap out the glasses that the design currently uses for other glasses The first step is to define a template for the glasses ZEMAX is allowed to choose Click on Tools Optimization Glass Substitution Template and set it up like so Glass Substitution Template if Use Glass Substitution Template if Exclude Glasses With Incomplete Data Standard Ww Preferred Obsolete Special i Maximum
6. Type Coat Scatter Scatter To Face Bulk Se Face 1 Splitter suface 1 Splitter surface x y Profile Use definitions below ll Save Coating 1 50 z Face ls Obs No Scattering Scatter Fraction o Lampbertia A OF hays All native ZEMAX objects use faces to define the various regions of optical interest in the object and these are documented in the object definition section of the manual Alternatively you can use Analysis Layout NSC object viewer to view individual objects If you click on a face of the object with the mouse that face will highlight and will be identified in the title bar of the window Update Settings Print Window Text Zoom Spin Page 67 of 74 6 2 3 Defining the Faces of CAD objects ZEMAX uses the Imported object to load objects created by CAD packages such as SolidWorks M CATIA and Pro Engineer These are defined by a potentially huge number of NURBS surfaces Some CAD programs create data files that have many more small surfaces than is useful for optical analysis For example a simple cylinder may be described in the CAD file by hundreds of small surfaces while for optical analysis only two or three different optical properties are applied to the entire object Rather than assign optical properties to each of the many surfaces it is usually more convenient to group CAD surfaces by assigning a single face number to all surfaces that form a continuous smooth portion of the object
7. Y Phase Initial Phase deg Coherence Length Pre Propagation Bulk Scatter Array Type Sampling Method Random y C Source Color System Wavelengths CIE 1931 Tristimulus XYZ x CIE 1931 Chromaticity xY p CIE 1931 RGB Saturated Spectrum File Uniform Power Spectrum Previous Object Next Object View Object Page 60 of 74 Any number of sources each with its own unique color can be defined For example if you have CIE 1976 u v data for a source where u 31 and v 0 5 ZEMAX can fit this color exactly using just four wavelengths SS gt TS Ds i A a a Pe Source Color CIE 1976 u v s u 10 31 v 10 5 Spectrum 4 Wavelengths From 0138 To 0 83 Spectrum File sample spectrum 1 sped Fit u 0 3100 v 0 5000 Previous Object Nest Object View Object In general you should use the minimum number of wavelengths that gives adequate color rendering Rays are then traced using either the specified or synthesized spectra of each source until they are detected by a Detector Color or Detector Polar object which can provide either True Color photometric or False Color radiometric data as required by the user For example open the sample file sub folder Colorimetry in the non sequential samples folder and open Example 1 two color mixing gives white White LEDs can be produced by using two phosphors in the LED die giving spectra in the blue and yellow For simplicity in this file
8. i 1 3D Layout Update Settings Print Window Tet Zoom 3D Layout a MO Double Gauss 28 degree field zmx Configuration 1 at 1 You can see that the second group of elements has been shifted in the y direction upwards in the 3D Layout and rotated around x the x axis points into the screen Click anywhere inside the 3D Layout window so that this window is active the title bar will appear brighter than the other ZEMAX Analysis windows The layout can be rotated by using the cursor keys and the PageUp PageDown keys or by the Rotation X Y Z controls in the Settings dialog box for this window Return to the Lens Data Editor and see that ZEMAX has now entered two new surfaces into the design These are called Coordinate Break CB surfaces Coordinate Break surfaces have no optical effect they just define a new coordinate system relative to the previous surface s coordinate system Click on the first CB surface and scroll to the right in the Editor See that the surface has a decentration in x then y and a tilt in x y and z If you filled in the dialog as shown above you should see a decentration in y of 2 mm a tilt about x of 5 degrees and have an order flag of 0 This means that the CB will execute left to right meaning that the decentration in x is done first then the decentration in y then the tilt in x etc Now look at the second CB It has a decentration in y of 2 mm and a tilt in x of 5 degrees This undoes the
9. this guide also points you to some of the other resources you can use to learn ZEMAX In particular the User s Manual is a detailed reference on all aspects of ZEMAX It is supplied in PDF format and is found in ZEMAX by clicking on Help Manual This guide refers to the various chapters and sections of the manual as it goes along as well as to some of the many sample files distributed along with ZEMAX Also our web based Knowledge Base at www zemax com kb is an indispensible resource for all ZEMAX users It contains tutorials worked examples and answers to many frequently asked questions Page 3 of 74 2 Installing ZEMAX To use ZEMAX there are two programs that must be installed on your computer The latest versions of both can be downloaded from www zemax com updates The two programs are e The ZEMAX installer which has a name like ZEMAX_YYYY MM_ DD exe where YYYY MM and DD are the year month and day of the release Different releases of ZEMAX are identified by their release date instead of a version number The same installer is used for both ZEMAX SE and ZEMAX EE and it contains all program files sample files and a detailed User s Manual in PDF format e The key driver installer ZEMAX is not copy es protected and may be installed on as many i machines as you wish ZEMAX is supplied with a black USB device which allows ZEMAX to run on the machine it is plugged into and determines whether the SE or EE feature set
10. Clear Detectors fan Ray Trace Control example Trace a Teis O Auto Update Note that the source object has a total ree 7 Ignore Emre power of 27 Lumens uses 30 layout rays git Ras Scatter Rays for drawing purposes and uses 1 million T Save Rays simple LXHL BDO1 LED model ZRD Analysis rays Now click on ZRD Format Compressed Full Data Analysis Ray Tracing Ray Trace a Control or press the Rtc button AS AN Lost energy thresholds 0 0000000 000 Click Clear Detectors and then press Lost energy erore 0 000000E 000 Trace to trace the million Analysis rays Page 52 of 74 then click Exit If you have more than one CPU in your computer the calculation will be automatically split up over all available CPUs Click on Analysis Ray Tracing Detector Viewer to see the data inside the Detector The Settings dialog for the Detector Viewer is very powerful and allows you to select incoherent illuminance Luminous intensity coherent illuminance and phase not meaningful in this case and luminance Multiple Detector Viewer windows can be open simultaneously to display multiple views of the same data You can also show the data in false color grey scale or look at cross sections through the data using the Show As control When using cross section views row or column 0 always means the central row column Data can be scaled linearly or logarithmically I 4 Detector Viewer o lea Updat
11. EXAMPLE A ASA 44 Page 1 of 74 5 2 OBJECT POSITIONING amp DEFINITION ratio eti 47 5 3 COMBINING SEQUENTIAL AND NON SEQUENTIAL RAY TRACING oocccocccccoccnccconconcncnoncnonnncncnnnnnnnnncnonnrnnonnrnrnnnrnronarannnanoss 50 54 TRACING RAYS ANDE TUNSDIA Sardinas 51 5 5 COMPLEX OBJECT CREATION ooccccccccccnnnnnnnnonnononononnnnnnnnnnnnnnnnnnn nn nnnnnnnnnnnnnnnnnnnnnnn nn nn nnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnnrnnonenenaninnnes 55 5 6 OPTIMIZING NON SEQUENTIAL SYSTEMS csccccccsseeccsesececeeseeecceuseecceaseecsaececseuseeeseaseeessageeecsaaseeessageeessasseessegsessseaes 57 r COOR TRY stated 60 6 POLARIZATION COATINGS amp SCATTERING EE ONLY oo ooccccnccncccccncccccncccccnconcnccononononcnononnnonnnnnnonnnnnnnnnononenennncnnnos 63 61 POARZATON narrar ie EEAS KASE ENIRE SEES EEEE saan ASENA EEAS ENAR 63 52 TANF COAT oeae EE E E EE etna E E E 64 BRING ER te gt elec AEE EE AERE EEE A E ood ta EEEE EEE E ENA E EE 68 GA PACO ATT TIN mentes A AE E AE EA AE AOE AAA 68 Bi INPORTANGE SAMPLING sacarina ea aE a aa O E A E vacated grata O A E A SAE 70 6 6 BULK AND FLUORESCENT SCATTERING ccccccccccccccccccecccsssssseesesaeeeeeeeceeeeeeeecessssusneeaaaeeeeececeeeeeeeeseesenensenaaaeeeeeeeeeeeees 71 FE CANAS Opera see erate crs cata a asas 73 7 1 GETTING TECHNICAL SUPPORT ccccceeeeeeesnsseeeeeeeeeececceesscseseeessaaeaeeeeeeeeeeeeecessssseseeesssaaaaaeeeseeeeeeeeseeseceeneeestsaaeeeeeeeeeess 74 ZEMAX is a registered trademark of
12. Factor 0 Telecentric Object Space L y I fa ne F p Lens units are millimeters by default which you can confirm by clicking on the Units tab of the dialog box We also have a requirement for the lens to be mechanically 2 mm larger in diameter than its working aperture so click on the Miscellaneous tab and enter a 1mm semi diameter margin like so General za Aperture Title Notes Units GlassCatalogs Environment Files Non Sequential Polarization Ray Aiming Miscellaneous Reference OPD Exit Pupil recommended Parada h ER lar Hie an Cile eS A recommended Jon Semi Diameter Margin Millimeters 1 Semi Diameter Margin o he ely Toon ate Pere ice Aumeze PO AA Note that ZEMAX works with semi diameters not diameters so a 1 mm semi diameter margin gives a 2 mm diameter margin Press OK We will now define the wavelength of the light This specification is a little vague on this important system parameter For example what is the visible spectrum and at exactly what wavelength should the system be f 5 We will assume that the visible region is that covered by the F d and C spectroscopic lines This is a very common assumption in visible system design We will further assume that the d line being the central wavelength should be the wavelength at which the f of the lens is defined We will therefore enter the System wavelengths as follows press the Wav button or click on System Wavelength
13. Locoted ot end of Light iyinet er E RRC Hee Size LE li Pinel I ik otal Hi Chaat Freeform optimization ZMK Configuration 1 af 1 Page 59 of 74 Note also that the detector object has shifted position and increased in size because of the pick up solves used Y 6 NSC ES Mi del Update Settings Print Window Text Zoom Spin Try experimenting with this file by repeating the optimization with the Damped Least Squares optimizer and with the Hammer optimizer 5 Colorimetry Colorimetry is the study of color which is the response of the human eye to optical radiation in the wavelength range 0 38 to 0 83 microns The color of any non sequential source object can be defined in many ways If the wavelength spectrum of a source is known it can be entered directly in the system Wavelength dialog up to 24 data points or via an ASCII text file up to 100 data points If the source spectrum is not known then the color coordinates of the source can be entered using several common definitions and ZEMAX will synthesize a spectrum of up to 100 wavelengths to produce this color The fitted color coordinates are provided along with an RGB equivalent of the fitted color on the Sources tab of the Object Properties dialog Type Coat Scatter ScatterTo Face Bulk Scatter Gradient Index Diffraction Sources Draw Birefringence Only source objects use these properties 4 Random Polarization Reverse Rays de Po dy X Phase
14. Note See the description of the Face Mode parameter of the Imported Object and the Face tab of the Object properties dialog in the User s Manual for full details of how to group NURBS surfaces into the appropriate number of optical faces 6 3 Ray Splitting Either sequential or non sequential ray tracing may be done while accounting for polarization effects or polarization may be ignored If polarization ray tracing is being used transmission reflection and absorption of optical energy is accounted for at all surfaces and bulk absorption by the optical media is also accounted for In pure non sequential ray tracing rays may also be split at interfaces In this case reflection losses are not just accounted for but a new ray is launched that takes the reflected energy away Because accurate reflection and transmission computation requires polarization information ray splitting is only allowed when performing polarization ray tracing Ray splitting can be turned off and in this case the transmitted path is always taken at a refractive interface unless the ray totally internally reflects The reflected path is of course always taken if the object is a mirror The layout above shows some of the ray paths possible in the beamsplitter example when rays are split There is only 1 input ray drawn The ray termination criteria defined under General Non Sequential are essential for efficient calculation when ray splitting is on It is advis
15. Start At h Ignore Lateral Color Relative X Weight 1 0000 Configuration Al z Overall Weight 1 0000 Cancel Save Load TER Help ZEMAX will then write out a merit function like so Page 33 of 74 I Merit Function Editor 1 339325E 001 Edit Tools View Help over tye weve om my ex ey target weignt varme 3 contrap ewes es Mp pp y O 2 BLE BLME Default merit function EMS spot radius centroid GO 4 rings 6 arms 3 BLNK BLNK No default air thickness boundary constraints 4 BLNK BLNK No default glass thickness boundary constraints BuxKjoperands for fiel 20 Each row in the Merit Function Editor contains an operand which computes some value The TRAC operand for example computes the radial point at which a specified ray lands on the image plane relative to the average of all rays from that field point Note that each TRAC operand traces a ray defined by its wavelength number and its Hy Hy Px Py normalized coordinates Different operands will take different arguments and the names of the arguments are given in the header row of the Editor Each operand that computes a value returns that value in the Value column of the editor The operand is also given a target value to achieve and a weight The merit function value is then computed as SWV T where Wi is the weight of the operand V is its computed value and T is its target value and the summation is
16. diameter wavelength and angular extent We now need to enter the first guess data for the optical surfaces in this lens system As we know we will be designing a cemented doublet we know we will need a total of six surfaces the OBJect surface STOp surface the front middle and rear doublet lens surfaces and the IMAge surface Click on the IMAge surface in the Lens Data Editor and press the Insert key 3 times to insert the correct number of surfaces and enter the following data ji Lens Data Editor Edit Solves View Help osa stanara me e _ _ sto se A E E E a stanaaza maaane marime 520000 a remanra wear tntinay 0 0000 Taal sia o gt F Because the specification says that the OBJect scene is a very long distance away from the lens we have set the OBJect surface thickness to Infinity You do this by typing the word Infinity without the quotation marks in the editor cell Do not enter anything in the semi diameter data column ZEMAX will work this out for you and include the requested margin so that the lens is larger than the incoming beam Page 29 of 74 I 1 Layout Update Settings Print Window Text Zoom Now our system has a requirement that it must be f 5 There is a simple way to achieve this just double click the radius of curvature of the last lens surface and choose an f number solve like so Curvature solve on surface 4 Solve Type F Numb
17. hold the left mouse button down and move the mouse The model will rotate and the axes of rotation are defined by the Spin Mode which maps the 2D motion of the mouse into the 3D geometry of the Shaded Model Update Settings Print Window Text Zoom Spin 3 Multiple Configurations ZEMAX can also work with multiple configurations or versions of a design This is typically used to model zoom lenses where the spacings between lenses changes systems where the temperature changes and systems where the angle of a scanning mirror changes amongst many others We will use this now to model a system in which the spot produced by a catalog lens is scanned by a mirror over the image surface ZEMAX includes the lens catalogs of all the major vendors so you can easily find catalog lenses Click File New to clear ZEMAX and click on Tools Catalogs Lens Catalog or press the Len button and configure the dialog box like so Search Crteria Vendor EDMUND OPTICS x ore EFL 100 D0 EPD 24 00 z S iw Use Effective Focal Length mm 45512 EFL 100 00 EPD 24 00 PS E ais EFL 100 00 EPD 22 86 3 1 Min 99 00 Max 101 00 pan M Use Entrance Pupil Diameter mm E Mac 48286 EFL 100 00 EPD 2400 P 51 as 20 ou 25 48774 EFL 100 00 EPD 24 00 P S 1 E ue 48825 EFL 100 00 EPD 24 00 P S 1 48965 EFL 100 00 EPD 24 00 P S 1 M Eai T Soheticdl 63810 EFL 100 00 EPD 24 00 P 51 Erpa 65467 EFL 100 00
18. lens on an MTF measurement rig use RMS wavefront error MTF improves aS RMS wavefront error approaches zero If you need further improvement use the various MTF operands described in the Optimization chapter of the User s Man ual to target MTF performance at specific spatial frequencies e If you are designing an afocal system like a beam expander switch the lens to Afocal Mode via the switch on the General dialog box Aperture tab and use RMS Angular Ra dius if you expect more than about 2 waves of aberration in the final system and RMS wavefront error if you expect less than 2 waves of aberration 4 9 2 Don t Optimize Aberration Coefficients Directly It is tempting to attempt to control the lens under optimization by targeting Seidel aberrations like SPHA COMA etc directly in the merit function and then using fifth order aberrations for better control see the macro fifthord zpl or the optimization macro ZPLO3 zpl for example While this is perfectly possible to do in ZEMAX we do not recommend it for the following reasons e Aberrations are difficult to compute in tilted and decentered systems or systems with components like aspheric surfaces diffractive components or GRINs The Gaussian Quadrature GQ method ZEMAX uses for RMS Spot Radius and RMS Default Merit Functions are exact to a specified order of wavefront aberration If you use n rings in the default merit function you then have control of all wavefront abe
19. object 1 and all other object numbers have automatically incremented The Lenslet Array object that serves as the reference for the homogenizer assembly is therefore now object 4 Null objects have no optical properties and so they are useful for defining reference and pivot points for example Position the null object at y 40 z 70 and then double click on the object type to show the object properties tab Page 47 of 74 Type Coat Scatter E Scatter To Face Bulk Scatter Gr Diffraction Do Not Draw Object On the Draw tab check the Draw Local Axis control On the NSC 3D Layout the Null object s local axes are now drawn note that local axes are never drawn in the Shaded Model Print Window Text Zoom LL LL ta O O CC et a SR ee ola par On the Non Sequential Component Editor s menu bar choose Tools Modify Reference Object Replicate Object Create Polygon Object Combine Objects 3 Asphe i Modify Reference Objects oe Create Source Ray From Last Geometry Error Insert Freeform Point Delete Freeform Point Export Polar Detector Data as Source File Save Detector Data Page 48 of 74 And set it like so Modify Reference Object First Object Object 4 r Last Object Object 4 Refer To 1h Cancel Hep ZEMAX will now modify object 4 s properties so that it is
20. of your ZEMAX key run Help About in ZEMAX to get this o A clear description of your problem Include the sample file that demonstrates the is sue if you can Use File Backup to Archive and send the resulting ZAR file This single file contains everything we need to reproduce your design exactly as you have it on your computer e You will get a response within a maximum of one working day and usually a lot sooner lf support for your key is not current you can renew it easily by sending an email to sales zemax com or your local distributor and requesting a quotation for support renewal Page 74 of 74
21. or three dimensional arrays of any object for example an array of Boolean objects y 3 NS cf Sh O di i aes el te Settings Print Window Text Zoom Spin Using the Array object is highly recommended over the alternative method of multiple object definitions for several reasons e t uses much less memory than the equiv Update Settings Print Window Text Zoom Spin alent number of individual objects typical ly only slightly more than one instance of the parent object e It employs sophisticated ray trace accel eration techniques to trace orders of magnitude faster than the equivalent number of individual objects e Itis less error prone than entering multiple objects and only one object needs to be updated or optimized to update or opti mize the whole array The Array Ring can also be used to create cir cular hexapolar and spiral arrays It has the same advantages as the Array object outlined above 5 5 4 The Source Object Any geometry object may be used as a source by using the Source object This is ideal for infra red and Narcissus analysis where the emissivity of opto mechanical components must be accounted for 5 6 Optimizing Non Sequential Systems Optimization is fully supported in both pure non sequential and hybrid non sequential sequential optical systems In pure non sequential mode there is no default merit function tool as non sequential ray tracing is too general a technology The most common w
22. reflects the blue i 1 NSC 3D Layout 1 Update Settings Print Window Text Zoom Page 71 of 74 Bulk scattering properties are defined on the Bulk Scatter tab of the Object Properties dialog Object 2 Properties Ea Diffraction l Sources l Draw Birefringence Type Coat Scatter ScatterTo Face Bulk Scatter Gradient Index Model E Mean Path 10 5 Angle 110 DLL lbulk_samp_1 dll Wavelength Shift Previous Object Next Object View Object The Wavelength Shift control allows definition of wavelength transitions during bulk scatter events The syntax is in out prob where in is the input wavelength number out is the output wavelength number prob is the relative probability that this shift will occur when tracing the in wavelength Multiple transitions may be defined using a semi colon separator For example if a single input wavelength 1 will shift to wavelength 2 50 of the time wavelength 3 40 of the time and the remaining 10 of the time will remain at the input wavelength then the wavelength shift string is 1 2 50 0 1 3 40 0 1 1 10 0 Page 72 of 74 7 What s Next Well done on working through this booklet This guide is by necessity brief and has only scratched the surface of what you can achieve with ZEMAX The goal was to get you started using ZEMAX in just an hour or two There is plenty that is not covered For example it does not discuss Tol
23. see the exported rays visit the ZEMAX User s Knowledge Base at www zemax com kb and search for SolidWorks to get advice on how to set SolidWorks importer options This lets you see easily the range of motion of the mirror the envelope of the rays and the optical components Multiple configurations can be exported as separate files as separate layers of the same file or all at once as done here Importing CAD objects is discussed in the non sequential ray tracing section of this Guide 3 9 Summary Congratulations You have finished the first part of the Getting Started Using ZEMAX guide By now you should be familiar with e The Lens Data Editor surface parameters and surface properties e How to configure Analysis windows by right mouse clicking the window to access the Settings dialog box e The normalized coordinate system used to define rays e The local coordinate system used to position surfaces e Multiple configurations of a design e Exporting optical components and ray sets to mechanical CAD packages These are fundamental concepts in using ZEMAX If you re not sure you get it yet review this chapter read the User s Manual and read the appropriate Knowledge Base articles until you re ready to proceed Page 26 of 74 4 Optimization So far we have loaded a lens file and used Analysis features to look at the performance of the system Optimization takes this to the next level ZEMAX will acti
24. EPD 24 00 P S 1 Br M GRIN 65487 EFL 100 00 EPD 25 00 P S 1 65507 EFL 100 00 EPD 25 00 P S 1 Mi Plano 7 Aspheric 65527 EFL 100 00 EPD 25 00 P S 1 65547 EFL 100 00 EPD 25 000 P 51 gg gt gt O Tia 67097 EFL 100 00 EPD 21 25 P S 1 67550 EFL 100 00 EPD 24 00 P S 1 Elements Singlet 67956 EFL 100 00 EPD 21 25 P5 1 Selected 27 out of 4060 files 43020 EFL 99 78 EPD 22 86 P S 1 Page 19 of 74 This searches for plano convex singlet lenses with focal lengths between 99 and 101 mm and Entrance Pupil Diameters between 20 and 25 mm Note that there are 27 lenses that meet these criteria out of the 4060 files included in the Edmund Optics catalog Select the lens 32481 and press the Load button ZEMAX then loads this stock lens i 1 Layout Update Settings Print Window Text Zoom 32481 PCX Total Axial Length 101 46538 mm Our goal is to design a scanning mirror that scans the focal spot through 10 around a nominal 90 reflection angle First note that the lens has been entered so that it is illuminated right up to the edge of its mechanical aperture Since the lens will be held in a mount of some sort we need to reduce the Entrance Pupil Diameter a little since this is a catalog lens the mechanical diameter is fixed Under General Aperture set the Entrance Pupil Diameter to 18 Check the Units tab to see what the Lens Units are Click anywhere on surface 2 Note that
25. Field Coordinates Normalized field coordinates H and H are used throughout ZEMAX its documentation and in the wider optical design literature The normalized field coordinate 0 1 for example is always at the top of the field of view in y whether the field points are defined as angles or heights and regardless of the magnitude of the field coordinates similarly the field coordinate 0 0 is always at the center of the field of view For example suppose 3 field points are defined in the x y directions using object height in lens units of millimeters at 0 0 10 0 and 0 3 The field point with the maximum radial coordinate is the second field point and the maximum radial field is therefore 10 mm The normalized coordinate H 0 H 1 refers to the location on the object surface as the field of view is defined in object height of x 0 y 10 mm The normalized coordinate H 1 H 0 refers to the object surface location 10 0 You can then define any point within the field of view of the lens by its Hx Hy coordinates as long as H H lt 1 This is referred to as radial field normalization as the normalized field coordinates represent points on a unit circle ZEMAX also supports rectangular field normalization in which the normalized field coordinates represent points on a unit rectangle Page 13 of 74 A Hy Fg al a A E ba 0 0 3 0 1 Maximum Y field La i A
26. Getting Started Using ZEMAX Version 2 1 Table of Contents t ABOUTTHS SUITE a eee ar 3 Z INSTALLINO Z2ZEVMAS ios 4 2 1 INSTANTE KEY DRIVER a LS 4 2 2 INSTALLING RA PREREQUISITES A tend lect aleaiely ee autces 4 2 3 INSTALLING ZENA esc eraser wea nents cn eaaceao r ays Aa 5 2 4 LICENSE CODE ts cia asco 5 2 5 NETWORK KE YS AND CLIENT T inae a a a AA a E 5 2 6 TROUBLESHOOTING e lcd e ace tas 6 2 1 CUSTOMIZING YOUR ZEMAX INSTALLATION aio 6 3 THE ZEMAX USER INTERFACES noo 8 3 1 TAE LENS DATA EDITOR arrea o da e o ae 8 3 2 ANALYSIS WINDOWS illes ati cede 10 3 3 MAE r TEMMEN tan dia 11 3 4 THEANORMALIZED COORDINATE SYSTEM aia 13 3 5 DEFINING amp POSITIONING SURFACE Sires am aa a 15 3 6 WORKING INET AREE DIMENSIONS 2 e aa E a a rete 17 3 7 MULTIPLE GONFICURATION S etea A a a 19 3 8 EXPORTING TO MECHANICAL CAD PACKAGES 00 AEEA E EAE EEEE A CATENE E 25 3 9 e o Hi A a E 26 E PAIZO IN por ooo eta 21 4 1 WHELENS SPECIFICA MON 0 taa aaa iaa 27 4 2 ENTERING THE BASIC SYSTEM a a a ai liceo dy 27 4 3 SETFUNOG VARIABLES ie uaida 32 4 4 DEFINING THE MERIT FUNG TION ati o atleta 33 4 5 OPTIMIZING THE LENS seceaasccu teas eea a udtusiad wceaaastane sans vavaamaw athesaan uaeveamaiinae yaa uave unin onan en inemanaeaeuaneue 34 4 6 THE HANME R OPTIMIZER sodio adds 37 4 7 ARE THERE ENOUGH FIELD POINTS tia 38 4 8 GLASS OPTIMIZATION atada 40 4 9 UPS FORSUCOESS UL DE TIM ON dido olaaa 42 S INON SEQUENTIAL RAY TRACING EE ONLY Fanlo 44 5 1 A SINPLE
27. Hx i o 0 1 0 Hx radial field Pa J ral j ye y LA Fd Meximum X field Note See the User s Manual chapter 3 Conventions and Definitions for full details of these conventions and all the basic definitions ZEMAX uses 3 4 2 Normalized Pupil Coordinates Similarly normalized pupil coordinates are also used throughout ZEMAX its documentation and in the wider optical design literature You define the system aperture using whatever definition is most useful and thereafter we use the normalized pupil coordinates Px and Py to define any point within a unit circle Therefore the point 0 1 represents a point at the top of the bundle of rays entering the system and 0 0 is a point at the center of the ray bundle no matter what the definition of system aperture is or what value it has 3 4 3 Using the Normalized Coordinates Re open the double Gauss 28 degree field sample file in order to undo any changes you may have made in the earlier sections Open the Field dialog box and note that the field is defined as angle in degrees and the maximum field point has a value of 14 This is a half angle and so the full field of view is 28 Note ZEMAX is always clear on the definitions it uses but these definitions are not universal in the optics industry Always clarify with your customers what definitions they use for important system specifications to avoid costly errors Then open the General dialog box and under the ap
28. MS RMS vs Field and configure it like so RMS Diagram Settings Use Dashes Use Polarization I 1 RMS vs Field Update Settings Print Window Text Zoom Poly 0 466 0 588 0 656 LENG ZHE Reference Centroid Conficuration 1 of 1 This plot shows how the RMS spot radius varies as a function of field with field as a continuous variable We are using 50 points across the 5 field and plotting the RMS spot radius for each wavelength individually and as a polychromatic average Note that the RMS spot never exceeds its value at the extreme fields of 0 and 5 Therefore two Page 38 of 74 field points provide adequate control in this design If the curve shows exceeds the value at the maximum or minimum field points add more field points as required Note If you change the number of field points or the number of wavelengths you must rebuild the merit function to include your changes into it A similar RMS vs Wavelength plot allows you to check that you have adequate control with the defined number of wavelengths as does Analysis Miscellaneous Chromatic Focal Shift and Analysis Miscellaneous Lateral Color Another excellent way to look at the optical behavior over field and wavelength is to use Analysis Image Simulation Image Simulation Configure it like so Source Bitmap Settings Guard Band Wavelength Field Convolution Grid Settings Image Sampling PSF X Points PSF
29. Radiant ZEMAX LLC Page 2 of 74 1 About This Guide Congratulations on your purchase of ZEMAX ZEMAX is the industry standard optical system design software combining sequential lens design analysis optimization tolerancing physical optics non sequential optical system design polarization thin film modeling and mechanical CAD Import Export in a single easy to use package Although ZEMAX is easy to use optical system design is a very broad area of engineering This guide is intended to get you started using ZEMAX quickly lt is the first place to start if you are new to ZEMAX or if you are returning to it after having not used ZEMAX for some time You may learn something even if you have used ZEMAX for many years We strongly recommend you take the time to work all the way through this booklet lt covers e Installing ZEMAX and customizing its appearance and file locations to your preference e Entering a simple sequential design e Understanding the normalized definitions ZEMAX uses e An overview of the multiple configurations capability e How to export components and rays to mechanical CAD packages e Optimizing a simple lens e Using some of the powerful tools ZEMAX makes available e Tilting and decentering optical components e Entering a simple non sequential system tracing rays and using detectors e Colorimetry e Thin Film Coatings e Surface bulk and fluorescent scattering As well as getting you started
30. Relative Cost 10 0000 gt Maximum Climatic Resistance CR Rown W Maximum Stain Resistance FR 1 0000 Maximum Acid Resistance SR 100 0000 Maximum Alkali Resistance AR 100 0000 Maximum Phosphate Resistance PR 100 0000 56 glasses meet these criteria Save As New Glass Catalog OK Cancel Reset We are telling ZEMAX to use only Preferred optical glasses a status flag that indicates the glass is easily available and does not have any unusual properties In addition each glass must cost no more than 10 times the price of N BK 7 the relative cost and must have a Climate Resistance factor of 2 or better and a Stain Resistance factor of 1 or better see the Using Glass Catalogs chapter of the User s Manual for full details There are a total of 58 glasses in the currently loaded catalog by default the Schott glass catalog is loaded that meet these criteria and these are the only ones that will be selected for substitution Then double click on the glass of surface number 2 which is currently N BK 7 and in the solve dialog box set a Substitute solve Glass solve on surface 2 solve Type Substitute e Cancel Repeat this for the F2 on surface 3 The Lens Data Editor should show an S status next to the glasses to indicate that these glasses may be substituted Page 40 of 74 Lens Data Editor Edit Solves View Help Infinity a standard miare 36 584 v 20 0000 al standar
31. USS Total Axial Length 132 98842 mm Page 15 of 74 lf you move the mouse across the Layout window you will see the Z coordinate change and as you move the mouse up or down the window the Y value will change The Lens Data Editor shows the following data for surface 1 Radius of curvature 64 2153 Thickness 8 1747 Glass SKZ Semi diameter PEAS Conic 0 Remember that any lengths where the units are not explicitly given are in Lens Units which are in mm for this file See System General and the Units tab The radius of curvature of surface 1 is 54 153 mm This is a positive number because the center of curvature lies in positive Z By contrast surface 7 has a radius of curvature of 25 685 mm because its center of curvature lies in Z Surface 1 s thickness of 8 747 mm means that surface 2 is located 8 747 in positive Z relative to surface 1 Thickness is therefore the distance along Z of two surfaces We refer to this as thickness in the editor rather than z distance because if you were to hold the lens formed by surfaces 1 and 2 in your hand you would naturally describe the lens as having a center thickness Surface 1 s Glass type is set to SK2 which means that the space between surface 1 and surface 2 is filled by a particular glass called SK2 Click on the SK2 glass in the editor and then click on Tools Catalogs Glass Catalogs or press the Gla button on the toolbar Glass Catalo
32. Use Polarization if Suppress Frame The ray will now be split into the unscattered ray and five scattered rays I 1 NSC 3D Layout Update Settings Print Window Tet Zoom Update this layout a few times and note that you always get the unscattered ray and five randomly scattered rays The number of scattered rays is defined by the Number of Rays parameter in the Coat Scatter tab of the Object properties 6 5 Importance Sampling A very large number of rays may need to be traced to find a relatively small number of scattered rays that strike an object of interest such as a detector ZEMAX supports two powerful ways to improve the efficiency of the scattering analysis The first method is to scatter a ray according to the scatter distribution but only trace the ray if the ray propagates towards an object of interest This method may be implemented by defining a Scatter To list of objects using the Scatter To tab of the Object Properties dialog box The Scatter To method works well for wide angle scatter such as Lambertian scatter and when the object of interest subtends a relatively large angle as seen from the scattering surface The second method is to always scatter the ray towards the object s of interest and then to normalize the energy the ray carries to account for the probability the ray would have actually scattered in that direction This method is called Importance Sampling Importance Sampling is gen
33. able to set the relative ray transmission reasonably high around 0 001 until the model is working well and more detailed results are needed ZEMAX also supports an option to randomly choose either the reflected or the refracted path rather than split the ray into two and trace both This is controlled by the Simple Ray Splitting switch on the Non Sequential tab of the General dialog box The decision to trace the reflected or the refracted ray is random with the reflection and transmission coefficients being interpreted as a relative probability of taking that path 6 4 Ray Scattering In addition to partial reflections at the surfaces of optical components rays can also scatter due to microscopic roughness of the surface ZEMAX supports many detailed models of scattering from optical surfaces including Lambertian used for very rough highly scattering surfaces Gaussian typically used for modeling the scattering of a well polished surface ABg K correlation and more In addition ZEMAX can import scattering data in a simple ASCII file format Although scattering can be used in sequential ray tracing see the Scattering tab of the Surface Properties dialog it is most useful in non sequential ray tracing where rays can go wherever they want to Scattering functions are applied to the faces of non Page 68 of 74 sequential objects in the same way as thin film coatings are on the Coat Scatter tab of the Object Properties tab Op
34. ase variations of the electric field which depend upon the angle of incidence the incident polarization and the properties of the two media and any optical coatings at the interface Polarization analysis is an extension to conventional ray tracing which considers the effects that optical coatings and reflection and absorption losses have on the propagation of light through an optical system Further scattering at the interface can also be considered Scattering is due to micro structure of the surface texture at a sufficiently fine resolution the surface of a smooth polished glass is really a rough surface with the result that the departing direction cosines are perturbed or scattered about their specular values Scattering can also occur during ray tracing through an optical material due to inclusions in the material This is referred to as bulk scattering 6 1 Polarization In addition to position and direction the amplitude and polarization state of a ray can be described by a vector E with complex valued components Ex Ey E2 Since the E vector must be orthogonal to the ray direction vector k then k E O and E Ey m E n 0 Where I m and n are the direction cosines of the ray Since we know the direction cosines we only need to specify the complex values of E and E as E is then defined The polarization can then be defined using a 2D Jones vector J J Jy where J and J are measured along the dire
35. ay to optimize a pure non sequential system is to use the NSTR and NSDD operands although other operands are also available NSTR is used to trace rays and it acts exactly like the Ray Trace Control dialog Page 57 of 74 NSDD is used to clear detectors and to read out detector data Any pixel can be read out directly but for optimization it is usually more useful to optimize on aggregate ray data like centroid location or effective widths in the spatial or angular domains By using negative pixel numbers in the NSDD operand ZEMAX will compute data like the average and standard deviation of all pixel data and spatial or angular centroids and RMS widths Note See Chapter 17 of the User s Manual for full details of NSDD and other non sequential optimization operands Open the sample file in the Samples Non sequential Miscellaneous folder called Freeform Optimization zmx This file contains a CAD part and source ray file supplied by Osram for their LB_T67c LED lt also contains a lightpipe the shape of which we wish to optimize i 1 NSC Shaded Model Update Settings Print Window Text Zoom Spin The lightpipe is a Freeform Z object which is defined by a set of y z data points ZEMAX fits a smooth curve through these data points and then rotates the curve around the z axis to form a rotationally symmetric pipe The pipe is currently just a cylinder but note that the y z data is set to be variable Note also that the z pos
36. ce Another commonly used Aperture Type is Object Space NA which is appropriate when the source is something like an optical fiber that radiates out in a defined numerical aperture Use Object Cone Angle if the source is defined by a source angle in degrees instead of NA There are other definitions available for less common requirements and several other tabs that define system level settings for the file Review these with the on line Help or see Chapter 6 of the User s Manual for full details 3 3 2 The Field Dialog Box The term Field is short for field of view Gr a Layout So ee and it can be defined in three ways one of which supports two options Update Settings Print Window Text Zoom e The height of the object scene being imaged e The height of the image being formed which may be chosen to be either a real or paraxial image height e The angle subtended by the object scene at the lens Whichever you choose it is defined by System Field or by pressing the Fie button Field Data Type Angle Deg f Object Height C Paraxial Image Height Real Image Height Field Normalization Radial vw Use X Field Y Field Weight VDX VDY VEX VEY VAN mip Jo fiom ooo jooo foooooo foooooo 0 00000 Pal fio foomo foooooo foooooo foooooo foooooo Dajo Jo fow 0 00000 0 00000 foooooo foooooo 0 00000 rye 7 o pr Y ine Page 12 of 74 3 3 3 The Wavelen
37. ction of the ray and have both a magnitude and a phase The 3D E vector is then constructed from the 2D J vector and the direction cosines of the ray The method used to define the initial polarization of a ray then depends on whether we are working with a sequential or non sequential system 6 1 1 Defining Polarization in a Sequential System The default polarization state of rays is defined in the General dialog box s Polarization tab Page 63 of 74 i General Aperture Title Notes Units Glass Catalogs Files Non Sequential Polarization Ray Aiming Convert thin film phase to ray equivalent Unpolarized dx 10 0000 Jy 0000 AX Phase 0 0000 Y Phase 0 0000 Method If an Analysis feature uses polarization but its Settings do not allow for the definition of the polarization then that calculation will use the settings here However many Analysis windows do allow the direct definition of the polarization state These windows default to this setting in the General dialog box but allow direct modification For example click on Analysis Polarization Polarization Ray Trace and you can define the ray coordinates and polarization state directly Polarization Ray Trace Settings 6 1 2 Defining Polarization in a Non Sequential System Non Sequential source objects can have their polarization state defined by double clicking on the Source object and going to the Sources tab W
38. d rear _ e2 s29 127 414 v mua stanara gt imei The glass substitution method is too complex for the local optimizer Instead use the Hammer optimizer Tools Optimization Hammer or press the Ham button and ZEMAX will quickly find the best glasses for this design Hammer Optimization al Ecg al le n Algorithm IDLS CPU 14 Auto Update Initial Merit Function 0 010342050 Current Merit Function 0 00781 603 Systems 452136 Run time 16 536 sec Check the glasses in the Glass Catalog to ensure they meet the specification The design now has an RMS spot radius below 19u everywhere across the field of view 101 1 RMS vs Field Update Settings Print Window Text Zoom RMS Spot Radius in pm a 1 3 z Y Field in Degrees RMS Spot Radius vs Field LENS ZMX Reference Centroid Configuration 1 of 1 Page 41 of 74 4 9 Tips For Successful Optimization 4 9 1 Use Physically Significant Merit Functions Before you start to design your lens think about how it will be tested and used Test methods fall into a number of broad categories e Imaging onto CCD arrays or less common photographic films RMS Spot Radius is usually a good performance indicator in this case If the final system is expected to have less than about 2 waves of aberration use RMS Wavefront Error instead e If you will test your lens on an interferometer optimize for RMS Wavefront error e If you will test your
39. d on scattering from tissue or fluorescent scattering Non sequential ray tracing assumes that there is no pre defined path for any ray A ray is launched and hits whatever object is in its path and it may then reflect refract diffract scatter split into child rays etc It is a far more general technology than sequential ray tracing and is therefore somewhat slower in terms of ray tracing speed Sequential designs can be converted easily to non sequential mode by using Tools Miscellaneous Convert to NSC Group 5 1 ASimple Example Click on File New to start a new DI ZEMAX EE 23000 C Users Alissa Documents ZEMAX SAMPLE ZEMAX design Then click On Editors System Analyse Tools Reports Macros o File Non Sequential mode A new New editor the Non Sequential Component On Editor NSCE will appear Save Save s The button bar will change and if you Y click on the Analysis or Tools menu items you will see that these menus are not the same as in sequential mode Sequential or Mixed Sequential Non Sequential Mode Use Session Files Backup To Archive File Restore From Archive File Non Sequential Mode The NSCE is very similar to the Lens Data editor or the merit function editor in look and feel and if you know how to use these editors the NSCE holds no surprises However in non sequential mode we deal with components or objects rather than surfaces Objects are f
40. e and if not go back through the exercise step by step to make sure your system is correctly set up Note Finally click on Reports System Check This invaluable utility checks your file for the most common setup faults Although not every possible fault can be caught by such a utility anything it does report should be checked and anything classed as an Error must be rectified before proceeding Then click on File Save As or press the Sas button to save the file as basic setup zmx 4 3 Setting Variables Our basic system setup is certainly an f 5 lens that meets the specification of aperture wavelength and field of view but it is not necessarily the best possible lens for the job In fact with only one curved surface it is highly unlikely to be the best possible lens for the job We are now going to optimize the lens to get the best possible performance First we will tell ZEMAX what it may change We do this by double left clicking on the parameter we want and selecting the variable solve Thickness solve on surface 1 Solve Type Or we can use the keyboard shortcut lt Cntl gt Z press and hold the Cntl button and then press the z button on the keyboard Note See Chapter 2 of the User s Manual User Interface for a summary of all the useful keyboard shortcuts ZEMAX has We will set a total of six variables Page 32 of 74 Lens Data Editor Edit Solves View Help a Seandaral__fro
41. e Break surfaces with pickups that tilt the mirror surface The two sets of Coordinate Breaks are nested such that the set added by the Tilt Decenter tool are inside the pair added by the Fold Mirror tool Page 22 of 74 il Lens Data Editor Edit Solves View Help Tilt About Y mo Standard a coordinarse Breck e coordinate Break coordinarse Break You can vary the 10 value by hand and watch the 3D layout update or click on Tools Miscellaneous Slider and configure it like so e Parameter 3 On Surface 4 Window All 0 Stop 10 Animate Save Ex Press the Animate button and all open windows will update as the Tilt About X parameter 3 of surface 4 is scanned Now exit the slider and click on Editors Multi Configuration LI Multi Configuration Editor Edit Solves Tool View Help Active 1 1 Config 1 The lens currently has only one configuration and the multiple configuration operand MOFF Multiconfiguration OFF is a placeholder that affects nothing and allows you to enter comments in the editor if desired Note The Multi Configuration Editor is used to define everything that is different between configurations We will define 5 configurations representing scan angles of 10 5 0 5 and 10 respectively Click on the Multi Configuration Editor and either click on Edit Insert Configuration four times or press the lt Shift gt lt Ctrl gt lt I
42. e Settings Print Window Text Zoom Detector Viewer 3 00E 905 Detector Detector Object 2 bs 2 708 005 Ray Database None 2 484005 Surface Row Column 2 108 905 Show As Cross Section A Scale 1 80E 005 Z Plane Show Data Incoherent Illuminance Smoothing Contrast Enhancement None y Minimum Plot Scale 000 Maximum Plot Scale 1300000 0000 Filter A 5 0000 Output Image File CA 3 008 004 Cancel Save load Reset Help nomom E X coordinate value Incoherent Illuminance Simple LED model 1 508 905 1 208 905 Incoherent Illuminance 9 00E 0046 Detector 2 NSCG Surface 1 Row Center Y 0 0000 000 Size 20 000 WX 20 000 E A Pixels 100 X 100 H Total Hits 993540 ue Peak Illuminance 2 98882 005 L simple LXHL BD01 LED model ZMX Total Power 2 6826E 001 Lumens Configuration 1 of 1 The data can also be smoothed by averaging the data in each pixel and its neighboring pixels The operation can be repeated the number of times specified by the smoothing parameter This improves signal noise at the expense of spatial or angular resolution 5 4 4 Ray Databases The Detector Viewers are very useful but sometimes you will want access to the ray data directly Repeat the ray trace press the Rtc button and select Save Rays Ray Trace Control Clear Detectors All Trace Auto Update Use Polarization Split Rays if Save Rays simple LXHL BDO1 LED model RD ZRD Format Com
43. e generally those properties that are set and then not changed To see these properties move the mouse over the Type cell of the chosen surface and double click Alternatively click anywhere on the chosen row and choose Edit Surface Type A multi tab dialog appears From the Surface Type drop down list you can select the type of the surface which can be aspheric diffraction grating toroidal etc Note See the User s Manual Chapter 11 Surface Types for full details of all the surface types that MA A jljl l jljljljlaala ii Surface 3 Properties Type Draw Aperture Scattering Tit Decenter Physical Optics Coating Surface Type x Surface Color Defaut Color y Surface Opacity 100 Row Color Default Color Make Surface Stop Make Surface Global Coordinate Reference Surface Cannot Be Hyperhemispheric Ignore This Surface Previous Surface Next Surface Spend some time exploring each tab The most commonly used tabs are the Type Draw Aperture and the Tilt Decenter tabs Press the Help button on each tab to read the on line Help Note Chapter 5 of the User s Manual Editors menu gives full details of all the Editors and their properties Page 9 of 74 3 2 Analysis Windows Analysis windows provide either graphical or text based data computed from the lens as entered in the Editor Analysis wndows never change the lens data they provide diagnostic information of
44. e license code see the Knowledge Base Article below See Knowledge Base Article on the EMAX website Take a screenshot of this dialog box use Alt Print_Screen and paste it into an email to Ssupport zemax com We will promptly send you the license code or further instructions Note Please do not phone for a license code License codes are complex multi character strings and cannot be reliably given over the phone Emailing the screenshot of the dialog box to us is the quickest most error free way of getting your license code 2 5 Network Keys And Clients ZEMAX can also be supplied with 5 10 25 and 50 user network keys Installation is almost identical except that the key driver and hardware key are installed on one computer called the keyserver machine and ZEMAX is installed on as many other machines as you wish the client computers When a client machine starts ZEMAX it looks to the keyserver machine to see if a license is available and if so ZEMAX starts Installation of the key driver on the keyserver machine is identical to the normal installation except that you obviously MUST allow the firewall settings to be adjusted to allow network access to the key Installation of ZEMAX on the client machines is also identical to the normal installation except that you must tell ZEMAX where to look for the keyserver machine after installation Navigate to whatever folder you installed ZEMAX in by default this is C Prog
45. ecompute the Analysis calculation The Save Load and Reset buttons allow default settings to be saved recalled or reset to factory defaults If you save the settings of any window those become the defaults for every file that does not have its own settings so your preferences automatically flow through all your work The Help button will bring up the on line help for the window Page 10 of 74 3 3 The System Menu In addition to the surfaces of the optical system we must also define the light that is incident on the optical system This is done with the System menu Update All Shift Ctrl U General Ctrl G Fields Ctrl F Wavelengths Ctrl W Mext Configuration Ctrl A Last Configuration Shift Ctrl A Or with these buttons on the button bar 1 E AA a de E PA j PUI I t J AL e ge a Fiel A E a Sel AS a a r li j a B al r ee kg y A 4 k 1 5 i 1 File Editors Tools Macros Extensions Window Heb New Ope Sev sas sac Res ll uva ural cen Fie wav f ee AAA pad GA d 3 3 1 The General Dialog Box The General dialog box contains settings that apply to the whole lens design The most important tab is the Aperture tab which defines how big the bundle of light coming into the lens on axis is Files Non Sequential Polarization Ray Aiming Miscellaneous Aperture Title Notes Units Aperture Type Entrance Pupil Diameter Aperture Value Apodization Type
46. ed or you may choose to make some surfaces aspheric and repeat the optimization with the aspheric parameters set as variables Note See Chapters 17 and 18 of the User s Manual and the ZEMAX Users Knowledge Base category on Optimization for full details and many examples of optimization 4 1 The Lens Specification Here is the specification of the lens we are to design Design a cemented doublet that works at f 5 over the visible region of the spectrum The field of view is 10 full field of view and the object is a very long distance away from the lens The lens aperture is 25 mm entrance pupil diameter and the lens must be at least 2 mm wider in diameter than the optical beam to allow for mounting 4 2 Entering The Basic System Press File New to clear ZEMAX and start a new design We will start by defining the incoming beam of light by its aperture wavelength and field of view The system aperture has been defined as 25 mm entrance pupil diameter with at least a 2 mm mechanical diameter to allow for mounting of the lens Click on the Gen button in the button bar or press System General and enter the Entrance Pupil Diameter as 25 Page 27 of 74 il General Files Non Sequential Polarization Ray Aiming Miscellaneous Aperture Title Notes Units Glass Catalogs Environment Aperture Type Entrance Pupil Diameter Yi Aperture Value 25 Apodization Type Uniform e Apodization
47. efines how many random rays to launch from the source when creating layout plots This is typically a small number say less than 100 and is used on ly for drawing purposes e Analysis Rays Defines how many random rays to launch from the source when per forming analysis This is typically a much larger number and may be millions or even bil lions of rays Page 51 of 74 e Power units Power is the total power over the defined range of the source The power units are specified by the system source units e Wavenumber The wavenumber to use when tracing random rays Zero means poly chromatic which chooses ray wavelengths randomly with the weighting defined on the wavelength data editor e Color The pen color to use when drawing rays from this source If zero the default color will be chosen The RGB values of each pen are defined under File Preferences Color Parametric sources will then use further parameters to define their radiance Source objects are not made of any material Rays once launched have no further interaction with source objects Rays are normally launched into air but can be launched inside some other refractive index if desired Define a geometry object with the correct shape and refractive index first and then locate the source object inside it and then use the Inside Of parameter to tell ZEMAX to launch the rays inside that object s refractive index Note Source objects must use the Inside o
48. en the sample file in Non sequential Scattering called ABg scattering surface zmx This file uses the ABg scattering model which is commonly used with measured scattering data Object 2 Properties Diffraction Sources Draw Birefringence Type Coat Scatter ScatterTo Face Bulk Scatter Gradient Index Face 0 All Faces Profile Use definitions below Coating None vel Face ls C No Scattering Scatter Fraction C Lambertian Number Of Rays C Gaussian Sigma ABg ect C BSDF ect None o S Transmit None C User Defined DLL Name Gaussian _X r dll File Name As it is based on measured data the total amount of energy scattered by the surface is defined by the data file Other scattering models like the Lambertian model require you to tell ZEMAX how much energy to scatter using the Scatter Fraction parameter on this dialog If ray splitting is turned off the ray will either scatter or not depending on the value of the Scatter Fraction parameter or equivalent measured data and a random number ZEMAX generates for each ray object intersection Update the NSC 3D layout and note that the ray shown in either scatters or does not scatter i 1 NSC 3D Layout Update Settings Print Window Text Zoom Page 69 of 74 On the Settings dialog select Split Rays as well as Scatter Rays NSC 3D Layout Diagram Settings y i Fetch Y Split Rays if Scatter Rays i
49. er F H i 1 Layout Update Settings Print Window Tet Zoom Try altering the radii of curvature of the other two surfaces and you will see that the f solve automatically updates to enforce the condition that the lens be f 5 A solve is the most efficient way to enforce a system constraint Note Read Chapter 16 of the User s Manual Solves in its entirety A solid understanding and use of solves is one of the hallmarks of the professional lens designer Page 30 of 74 Now we will bring the lens into focus Click on Tools Miscellaneous Quick Focus and set it up like so Quick Focus Spot Size Radial C Spot Size X Only AMS Wavefront Spot Size Y Only W Use Centroid Update the Analysis windows to see the final basic setup 0 Layout ias Update Settings Print Window Text Zoom Lens Data Editor Edit Solves View Help SE MECO IIS ECC ee scandaral mesme gt 50 000 a seandaral_frone maramice 5 0000 scm a standard maso tasinaey 5 0000 a ma scanderal mem dS il i i Open a spot diagram by clicking on Analysis Spot Diagrams Standard or by pressing the Spt button on the button bar Page 31 of 74 2 Spot Diagram Update Settings Print Window Text Zoom LENS IMK Configuration 1 af 1 The RMS spot radius is 143u on axis and about 169u at the 5 field point Check that you get the same data as shown her
50. erally superior to the Scatter To method if the scatter is narrow angle or the object of interest subtends a relatively small angle as seen from the scattering surface Open the sample file in Non sequential Scattering called Importance Sampling Demonstration zmx This shows directly the benefit of using Importance Sampling Rays Page 70 of 74 are always scattered to the desired object in this case a detector and the resulting signal noise ratio is therefore far superior 1 NSC 3D Layout Update Settings Print Window Text Zoom Note See the section How to Model Scattering Efficiently in Chapter 12 of the User s Manual for full details of this important capability 6 6 Bulk and Fluorescent Scattering Bulk scattering models the random scattering of rays while propagating through a solid object This may be a very rare event like scattering from inclusions in optical quality glass or a very common event like scattering in biological tissue samples ZEMAX includes several bulk scattering models including Henyey Greenstein and Rayleigh scattering In addition rays may change wavelength when bulk scattered usually to longer wavelengths Open the sample file in Non sequential Scattering called Fluorescence Example zmx This file uses two wavelengths 1 blue and 2 red The source radiates only in the blue and this light enters a medium that scatters the light in angle and wavelength A beamsplitter transmits the red and
51. erancing Physical Optics thermal analysis multi beam interference in non sequential mode and many of the powerful analysis and optimization capabilities of ZEMAX Here are some other resources that will help you e The ZEMAX Knowledge Base at www zemax com kb This is an indispensible resource for ZEMAX users and contains hundreds of articles including tutorials answers to frequently asked questions and examples lt is structured into categories and has a powerful search engine to help you find articles of interest easily e The ZEMAX User s Manual is distributed with ZEMAX as a PDF file Click on Help Manual within ZEMAX This gives detailed instructions on the use of everything in ZEMAX You may print out all of the manual or only those pages you wish if you prefer printed materials e The on line Help which you can get by pressing F1 on the keyboard or clicking the Help button in dialog boxes e Radiant ZEMAX and its team of international distributors offer dedicated training classes on the use of ZEMAX Courses are held from introductory to advanced level and cover all aspects of sequential lens design illumination stray light programming ZEMAX and more See www zemax com training for more details Page 73 of 74 7 1 Getting Technical Support Please contact support zemax com or your local distributor if you need help in using ZEMAX Technical support is available to customers with current technical support all busi
52. erture tab note that the system aperture is defined as Entrance Pupil Diameter value 33 33 Go to the Units tab to see that the lens units are millimeters so the EPD is 33 33 mm Lastly open the Wavelength dialog box and note that the design uses three wavelengths at 0 4861 0 5876 and 0 6563 microns respectively The primary wavelength is set as wavelength number 2 which is 0 5876 microns Now click on Analysis Calculations Ray Trace This is the most fundamental calculation in ZEMAX the tracing of a single ray Right mouse click on this window to bring up its Settings dialog box Ray Trace Settings Page 14 of 74 Note how you can define any ray by where it starts on the object surface in normalized Hx Hy coordinates and where it goes to in the pupil in normalized Px Py coordinates Try tracing some rays and look at the data provided by this feature You are given the x y Z position of the ray the direction cosines of the ray and the path length of the ray at each surface of the system This is the fundamental data on which all the calculations in sequential ray tracing are based Note also that instead of defining arbitrary field coordinates Hx Hy you can also define the starting coordinates of the ray by the field point number Ray Trace Settings Global Coordinates e Direction Cosines Type Load Since field point 3 defined the maximum radial field it is at 0 1 in normalized field co
53. f parameter when the source is placed inside a geometry object otherwise incorrect ray tracing will result 5 4 2 Detector Objects Rays are detected by Detector objects Almost any kind of geometry object can be used as a detector also but the dedicated Detector objects are designed for the task of displaying spatial and angular data and provide the controls users need to represent data the way it is measured experimentally The most common type of detector object is the Detector Rectangle This is a two dimensional array of pixels similar to a CCD array It is most commonly used with the material ABSORB so that rays terminate upon being detected but it can also be set as a MIRROR with coating if required to be discussed later or its material may be left blank to indicate air Note that when the material is left blank rays are not perturbed in any way by being detected This can be useful but care must be taken as the detector may appear to not conserve energy if a ray interacts with it multiple times without losing any energy 9 4 3 Tracing Analysis Rays Open the sample file Samples Non sequential Sources Simple LXHL BDO1 LED model ZMX This file contains just two objects a Source Radial set with data taken from the LumiLeds LXHL BDO1 LED datasheet and a Detector Rectangle set to 100 by 100 pixels Note Read the detailed description in Chapters 14 and 15 of the User s Manual of both these objects before proceeding with this
54. g Catalog SCHOTT AGF eee ee C a Glass A 11 28189012 000 DO 13 8000E 006 SFL5 727191640E 003 DI 141008008 2 57738258E 001 D2 2280601 242823527E 002 EO 6 4400E 007 Rename SK2 K B6SI86M0E0m Et 8 0300 4011 Fomula Sellmeier 1 3 11 10377773E 002 Lk 11 0800E 001 Status Obsolete vw A o O Nd 1 607381 Vd 56 6501 PO Tgp 0 Ignore Thermal Expansion p 3 55 Exclude Substitution dPgrF 0 0008 Meta Material Negative Index Minimum Wavelength 0 31000000 Maximum Wavelength 1232500000 Melt Freq 1 E Comment TO ee ee Rel Cost 2 09 och ka mm fpo sR i220 aR 100 PR 230 Save Catalog Insert Glass Sort By gt Mame tt Save Catalog As Cut Glass Glass Report Catalog Report Reload Catalog Copy Glass Transmission Compute NdVd o sr Fit Index Data Fit Melt Data This shows that SK2 is a glass in the Schott catalog and it gives all the data ZEMAX knows about the glass Note A full discussion of this dialog is outside of the scope of this Guide See the User s Manual Chapter 21 Using Glass Catalogs for full details Next see that surface 2 has no entry for its Glass column and is instead blank That means that surface 2 is made of Air at Standard Temperature and Pressure Both temperature and pressure can be changed both at a system level and on a surface by surface basis This has important but subtle effects First the index of refract
55. gth Dialog Box The wavelengths dialog box defined under System Wavelength or by pressing the Wav button is used to set wavelengths weights and the primary wavelength of the system Wavelength Data Use Wavelength um Weight Use mai osma CS na w m2 losses O 14 055 ma 06562725 Jr 115 pa 4 T 16 0 55 5 10 55 17 10 55 6 1055 18 0 55 F 10 55 rT 719 1055 8 0 55 rT 20 10 55 9 70 55 a 0 55 10 0 55 22 1055 ii 1055 123 10 55 1112 055 24 0 55 Primary a Steps From cs Cancel Help Save Load Wavelengths are always entered in microns Wavelength weights can be used to define relative spectral intensity or simply to define which wavelengths are most important in a design The primary wavelength is used as a default wavelength for example if asked to compute effective focal length ZEMAX will compute it at the primary wavelength if no wavelength is specified 3 4 The Normalized Coordinate System Because there are six ways to define system aperture and four ways to define field of view it is convenient to work in normalized coordinates When performing the initial setup of your system you should choose the most appropriate aperture definition and the most appropriate field definition and enter the data for both of these Subsequently all calculations use normalized units and you do not have to refer to the specific values entered or definitions used 3 4 1 Normalized
56. h self terminates when it decides it can make no further progress the Hammer optimizer will hammer away until the user tells it to stop Click on Tools Optimization Hammer Optimization or press the Ham button in the button bar Then click the Start button in the dialog Hammer Optimization lo E E ninae Ses HCPU 4 Auto Update Initial Ment Function 0 010343104 Current Ment Function 0 010342050 Systems 1458773 Run time 50 560 sec As this design is fairly simple it will not make much further improvement to that shown here In more complex designs Hammer is invaluable in extracting the best performance from the lens In this case the RMS spot radius improves to 13 5u on axis and stays at about 26 14 at the 5 field point Page 37 of 74 2 Spot Diagram Update Settings Print Window Text Zoom LEKS IHME Coni igurasat icn loci i Note The other global optimization algorithm Global Search is used to provide starting points for subsequent optimization and is not suitable for such a simple design as this See Chapter 18 of the User s Manual Global Optimization for full details 4 7 Are There Enough Field Points We optimized this lens using just two field points at 0 and 5 Although the RMS spot radius looks well controlled at these two points how do we know that at some intermediate field point the performance of the lens does not degrade Click on Analysis R
57. hole system 5 3 Combining Sequential And Non Sequential Ray Tracing Most imaging systems are well described by the orderly sequential approach used in the Lens Data Editor However there are cases where an otherwise sequential system has some region in which there is a need for non sequential ray tracing A classic example is the Abbe prism in which different parts of the beam interact with different faces of the prism in a different order to other parts of the beam See for example SamplesiNon sequential Prisms Abbe roof zmx In this case the system is set p up initially just like any other 2 Shaded Model sequential system and then a Update Settings Print Window Text Zoom Spin special sequential surface type called a Non Sequential Component is used This acts like the entry port into the non sequential world defined in the non sequential component editor The parameters on the Non Sequential Component surface in the Lens Data Editor define the location of the exit port which is how rays come back to the sequential ray tracer This is referred to as hybrid or mixed Sequential Non sequential ray tracing When a sequential ray hits the Non Sequential Component surface in the Lens Data Editor it is passed to the non sequential ray tracer and it interacts with whatever objects are defined in the NSC Editor and are in the ray s path When the ray hits the region defined by the exit port in the Le
58. inction 0 400000 IPS io 70 0 000000 0 460000 LSO LLO 0 000000 Ds ODO 12319760 0 000000 0 700000 Les USO 0 000000 0 800000 Lea oUb 0 000000 1 000000 e ce t 0 000000 2 000000 1 367840 0 000000 2 000000 1 364260 0 000000 Page 65 of 74 This listing gives the complex refractive index defined as n n ik where n is the usual index of refraction and k is the extinction coefficient As the material MGF2 is defined as having positive n and zero k it is a pure dielectric The material ALUM however Material Name ALUM 1 data point s Wavelength Index EXCIACELON Os 950000 0 700000 e 000000 has index lt 1 and negative extinction and so is a metal the ZEMAX convention is that extinction is negative for an absorbing medium Coatings can be made up of any number of dielectric and metallic layers the layer thickness can be constant or tapered and repetitive loops of coatings can be easily defined If you do not have the coating prescription ZEMAX supports several IDEAL coatings which allow you to just specify reflection and transmission and also TABLE coatings that are similar to IDEAL coatings except the transmission and reflection may be a function of incident angle and wavelength and may be specified separately for S and P polarizations Now click on Analysis Coatings Reflection vs Angle to see the performance of this coating on an SK2 substrate 4 Reflection vs Angle Update Settings Print Window Text Zoom E o
59. ing that identifies exactly the conditions you want to investigate For example to select rays that must have either a hit object 7 and object 9 but did not reflect off object 6 or b missed object 2 the filter string would be H7 amp H9 amp R6 M2 Filter strings are your most important tool for detailed system analysis They can also be used with ray databases both prior to saving the ray database and with the saved data For example in stray light simulations you may have to trace millions of rays to get one that finds its way to the detector By saving to disk only those rays that hit the detector you can produce a manageable data set for further study You can replay ray databases through the ray database viewer the layout plots and the detector viewers and add further filters to the filtered data The ray database viewer will also let you filter a ray database and save the sub set data into a new file Note Read the Filter String section of Chapter 12 of the User s Manual NSC OVERVIEW for full details of this important capability 5 5 Complex Object Creation No matter how many objects we add to ZEMAX you may still sometimes need an object that is not directly available There are however ways to manipulate existing objects so as to create precisely what you need Page 55 of 74 5 5 1 The Overlapping Objects Rule When two or more objects occupy the same region of space a simple rule applies The pro
60. ion of glass depends upon both temperature and wavelength relative indices which are measured with respect to air also change with pressure Second glass expands and Page 16 of 74 contracts with temperature which can change the radius thickness or other dimensions of a lens Third the distances between lenses change due to the expansion and contraction of the mounting material The thermal analysis features of ZEMAX can account for all these effects ZEMAX can be used to analyze and optimize a design for any specific temperature or for a range of temperatures This is outside of the scope of this Guide however and we will assume that the whole lens is at 20 C 1 Atm pressure Note See Chapter 22 of the User s Manual Thermal Analysis for full details of the comprehensive temperature and pressure modelling capabilities of ZEMAX The Semi Diameter column shows the radial height of the surface it is called Semi Diameter to avoid confusion with radius of curvature This can be computed in two ways automatically by ZEMAX the default or directly entered by the user The automatic calculation sets the semi diameter to ensure that the edge rays always pass through the lens This means that the lenses are just big enough to pass the full aperture of rays from across the field of view Usually lenses are made a little larger than this so there is some unused glass that can be used to hold the lens in its mount with
61. is required objects can be positioned relative to other objects which we will discuss later Because rays can be split into transmitted reflected and scattered components as each ray splits it contains less and less energy We need to put some limits on the ray tracing to prevent ZEMAX from tracing rays with insignificant amounts of energy This is defined in the General dialog box in the Non Sequential tab iil General O T tle Notes Units GlassCatalogs Environment Files Non Sequential Polarization Named Filters Madmum Intersections Per Ray Maximum Segments Per Ray Madmum Nested Touching Objects Glue Distance In Lens Units Missed Ray Draw Distance In Lens Units Madmum Source File Rays In Memory Simple Ray Splitting Retrace Source Rays Upon File Open Cancel Apply Help Page 46 of 74 Try varying this parameter and observe how it affects the number of child rays produced Set it to 10 and note you get fewer rays at 10 you will get many more 5 2 Object Positioning amp Definition The Non Sequential Component Editor provides an easy way to define the non sequential optical system and the inter relationships between components Open the sample file in the Samples Non sequential Miscellaneous folder called Digital Projector Flys Eye Homogenizer zmx The system contains an elliptical source volume that approximates the shape of the fireball in an arc lamp inside a parabolic mirr
62. ition and x y halfwidths of the detector object are locked to the Freeform z object by pickup solves These ensure that the detector will always be just in front of the output face of the lightpipe as the pipe s length is varied during optimization and adjust the width of the detector so it always captures all the light from the output face as the width of the output face changes The primary goal for this light pipe is that it should give the highest brightness in the forward direction Therefore its luminous intensity should be as high as possible and the width in angle space of the luminous intensity plot should be as small as possible In addition there are some mechanical constraints on the maximum and minimum widths and length of the lightpipe that must be met Open the Merit Function Editor and examine the merit function First the detectors are cleared and then rays are traced Then we compute the RMS angular width of the detector data by using pixel 9 which is RMS width and Data 2 power unit solid angle The starting beam has an RMS angular width of 50 and a peak luminous intensity of 0 35 Im sr Page 58 of 74 3 Detector Viewer located at end of lightpipe Update Settings Print Window Text Zoom ay ES g Ea amp Ss 8 lt a 7 7 x VW Optimization Example a RT ma Lightpink Cater T Size I ET 00 to 30 00 W dg Pixels 161 E ak Teal diss io ei iesit te ter sien Freeform
63. ject You should now have two identical source objects Modify the parameters of one of them as follows 1 NSC 3D Layout oc oC fe Z position 2 0 Update Settings Print Window Text Tilt About X 15 0 Zoom TELE ADOUE Y 180 0 Do not change any other parameters Update the layout as you make each change so you can see what is happening You should see two sources one on either side of the lens On the Settings of the Layout plot select the options to Split Rays and Fletch rays This simple example shows the key benefits of non sequential ray tracing e You do not have to tell rays where to go Rays are launched and then interact with whatever objects are in their path 1 NSC 3D Layout Po LE E Update Settings Print Window Text Zoom e When a ray hits a refractive object part of its energy is reflected and part is transmitted ZEMAX can produce child rays that take the reflected energy and these child rays then interact with what ever is in their path and in turn produce children of their own which can have children of their own etc e As well as being partially reflected and refracted rays can also scatter at the surface of an object or inside its volume called bulk scattering to distinguish it from surface scattering e Sources objects and detectors are placed in a global coordinate system and can be po sitioned and tilted independently of each other In addition if it
64. l Object 1 Properties E Type Coat Scatter ScatterTo Face Bulk Scatter Gradient Index Diffraction Sources Draw Biretingence Only source objects use these properties Random Polarization Pre Propagation 0 000000 Bulk Scatter Array Type None Sampling Method 6 2 Thin Film Coatings ZEMAX has an extensive thin film modeling capability to support the polarization analysis Multilayer film dielectric and metallic coatings may be defined from either a predefined or user defined material database Many thin film codes like The Essential Macleod TFCalc and Film Star export coating designs directly in ZEMAX format Page 64 of 74 Coatings may be applied to either dielectric or metallic substrates Coatings may be composed of arbitrary layers of arbitrary material each defined with a complex index of refraction with full dispersion modeling in the coating materials Substrates may be glass metallic or user defined Coating layers may be of uniform or varying thickness and loops of replicated coating stacks can be easily created ZEMAX automatically reverses the coating layer order if surfaces go from air to glass then glass to air so the same coating may be applied on many surfaces without the need to define mirror image coatings Coatings are defined in a file with the dat extension This file is located in the coatings folder which by default is My Documents ZEMAX Coatings This folder can be m
65. ne tasinaey v s o000f v 0507 Pal standard rea 77 505 21 a65 v ma stenas gt ea AL al The status flag V indicates variables that ZEMAX may change the values of just as the F flag means that the rear surface s radius of curvature is set by an f solve As ZEMAX modifies the values of the variables the f solve will automatically update to maintain the lens at f 5 4 4 Defining The Merit Function Next we will build the merit function for this design Click on Editors Merit Function to open the Merit Function Editor This Editor is similar to the Lens Data Editor in functionality but where the Lens Data Editor contains the details of the lens design the Merit Function Editor contains the design goals or specifications you want the lens to achieve Then click on Tools Default Merit Function DI Merit Function Editor 0 000000E 000 Edit Tools View Help Update Default Merit Function Do Save Load Merere Because this is a focal system we want the smallest RMS spot radius choose RMS Spot Radius relative to the centroid and set the number of rings to 4 we will discuss this in more detail later for now just make these changes Default Merit Function Optimization Function and Reference RMS Y Spot Radius Gaussian Quadrature 0 Rectangular Aray COS Thickness Boundary Values Glass Min oo o Max 1000 Edge oO Air Min oo o Maz 1000 Edge oO i Assume Axial Symmetry
66. ness days except US public holidays from 7 AM to 4 PM Pacific Time via ZEMAX support and at other times via our team of international distributors Note It is vastly easier to resolve a technical problem with a sample file that demonstrates it Of course many customers are concerned about the confidentiality of their designs We do not undertake any product development contract work Therefore if you have a technical question you can be sure that you are not explaining your work to someone who may be working for a competitor or bidding against you for the same job Our goal is simply to help you use ZEMAX most effectively If you are still uncomfortable about sharing your design file try simplifying it to the bare essentials necessary to show the problem or use one of the gt 100 sample files supplied with ZEMAX instead Then please follow these steps e Make sure you are running the current version Press Help Check For Updates f you are eligible for technical support then you are eligible to run the current version Make sure you can reproduce your problem with the current version as it contains fixes for all known bugs e Run Reports System Check to test your file for common setup errors e Email a full description of the problem to support zemax com or your local distributor Please be sure you include o Your name organization email address and phone number in case we need to talk directly with you o The serial number
67. ngs il Ray Trace Control fol meson Clear Detectors All Trace T Auto Update HCPU 4 i Use Polarization i Ignore Errors i Split Rays Y Scatter i Save Rays led model 7RD RD Format Compressed Full Data Filter Use the Ray Database Viewer to view the ray histories Note that as ray splitting is on you can use the option expand into branches to identify each child ray separately 5 4 5 Filter Strings Because ZEMAX knows the history of every ray it has traced we can use filter strings to identify rays that meet specific conditions easily For example in the led model zmx file object 2 is a reflector behind the source Some rays are fired forwards and never see this mirror while others move in the opposite direction hit the reflector and then travel forwards Page 54 of 74 I 4 NSC 3D Layout Update Settings Print Window Text Zoom 4 NSC 3D Layout Update Settings Print Window Text Zoom NSC 3D Layout Diagram Settings Fetch Rays Seale Factor Split Rays Rotation x Scatter Rays Rotation Y Use Polarization Rotation Z W Suppress Frame Offset X Configuration All Offset Y 1 Offset Z Color Rays By Source Surface Filter Re Ray Database None Cancel Save load Reset Help IR2 will show those rays that do NOT reflect from object 2 i e rays that propagate forwards initially You can AND OR NOT XOR etc multiple filters to produce a filter str
68. ns Data Editor it is transferred back to the sequential ray tracer and interacts with the subsequent sequential surfaces A sequential system can contain any number of Non Sequential Component surfaces The objects inside each Non Sequential Component group are independent of each other You can easily switch between non sequential component groups by clicking Edit Next Group in the NSCE menu bar Page 50 of 74 i Mon Sequential Component Editor Component Group on Surface 2 Jj Solves Tools View Help Object Properties Ctrl Enter E Object Mext Group N Shift Ctrl D Edit Object If a ray does not hit the exit port it is terminated and it does not return to the sequential ray trace Note The marginal and chief rays must be traceable through NS groups otherwise ZEMAX cannot compute important sequential parameters like pupil positions and f 5 4 Tracing Rays And Getting Data Ray tracing in hybrid non sequential mode works exactly as it does in sequential mode except that there is no paraxial ray tracing inside an NS group In pure non sequential we use source objects to launch rays and detector objects to get quantitative information 5 4 1 Source Objects Source objects are objects that launch rays into the optical system with the appropriate spatial and angular distributions to represent the radiance of the real sources in your system Source objects fall into two categories e Parametric
69. nsert gt keys simultaneously four times so that a total of five configurations results Multi Configuration Editor Edit Solves Tools View Help Active 1 5 Config 1 Config 2 Config 3 Config 4 Config 5 Each line in the Multi Configuration Editor is an operand that acts on a parameter in the Lens Data Editor or some other System parameter and allows its value to be changed Move the mouse over the MOFF operand and double left click to edit the operand All Page 23 of 74 the multiple configuration operands ZEMAX supports can be selected from the drop down list in the resulting dialog Set it up like so Multi Config Operand 1 Operand PRAM surface 4 Mirror Tilt The PRAM operand picks up parameter data in this case parameter 3 of surface 4 and enters its current value into the editor Edit this value as follows LI Multi Configuration Editor Edit Solves Tools View ream TE a a a T Note See the User s Manual Chapter 20 Multi Configurations for full details of all multi configuration operands Use the lt cntl gt A keys to change the current configuration and note that all open windows update to show the data for whatever configuration is current Configure the 3D layout window like so 3D Layout Diagram Settings First Surface 324 Wavelength Last Surface Field Number Of Rays Seale Factor Ray Pattem Delete Vignetted Hide Lens Faces if Hide Lens Edges i Su
70. odified by clicking on File Preferences Folders ZEMAX is shipped with a file called coating dat which contains sample data Note You should not edit coatings dat as it is provided by the ZEMAX installer and will be overwritten when you next install an update il General Non Sequential Polarization Named Filters Title Notes GlassCatalogs Environment Files Coating File Scatter Profile ABg Data File GRADIUM Profile With the coating data in place ZEMAX computes the diattenuation phase retardance reflection transmission or absorption of any coating as a function of wavelength or angle 6 2 1 Adding Coatings to Sequential Surfaces Open the sample file Sequential Objectives Double Gauss 28 degree field zmx again This uses the supplied coatings dat file Scroll to the far right hand edge of the Lens Data Editor Note that the coating AR has been placed on all surfaces Now click on Tools Coatings Coating Listing Scroll down to find the coating AR Coating Name AR 1 layer s Material Thickness Absolute Loop Taper MGF2 0 250000 0 O Coating thickness is given in units of waves at the primary wavelength unless the absolute flag is non zero in which case the coating thickness is in um independent of wavelength The coating AR is therefore a 1 4 thick layer of the material MGF2 which is defined earlier in the coating dat file Material Name MGF2 8 data point s Wavelength Index Ext
71. on Automatic Targets 1 Cycle Variables 5 Cycles Initial Merit Function 0 078514514 10 Cycles Current Mert Function 0 010343104 50 Cycles Status Idle Inf Cycles Execution Time Algorithm Damped Least Squares CPU 4 7 Auto Update And the RMS spot radius is now 13 6u on axis and about 26 1 at the 5 field point but the lens design is far more reasonable fl 4 Layout Update Settings Print Window Text Zoom Total Axial Length 238 6 7T056 om Page 36 of 74 2 Spot Diagram Update Settings Print Window Text Zoom _ Zh Configuration 1 of 1 The key point is that for successful optimization the merit function should contain both the optical targets you want to achieve plus constraints that will prevent ZEMAX from producing unwanted design shapes Typical constraints include the thickness of elements weight maximum acceptable distortion etc Note You should read all of Chapter 17 of the User s Manual Optimization but in particular the sections Optimization Operands and Understanding Boundary Operands 4 6 The Hammer Optimizer We have used the local optimizer which improves lens design using a particular algorithm described in the User s Manual After this optimization the next step to run the Hammer optimizer which is one of several global optimization methods ZEMAX provides This exhaustively searches for improvements and unlike the local optimizer whic
72. on this object at any x y z location and tilt it about x y z You can then enter the glass type the object is made from and its defining parameter data Enter the following data All positions and tilts 0 0 Glass Radius 1 Conio 13 Clear 1 Edge 1 Radius 2 Conic 2 Clear 2 Edge 2 o W EN J Cook 1 0 FOONOODOouy era O 00 You should see the lens as drawn in red at the top of this page This is a fully parametric lens modeled as a solid object and not a collection of surfaces Next click on the lens object in the editor again and press the Insert button to create a new Null Object Double click the new object and in the Type parameter select Source Ray object Enter the following data All parameters are 0 0 except Y Position Elia A position se Tilt About xX LOs Layout Rays i You will then see this ray trace as per the second layout plot above The ray is traced from the source to the front face of the lens and then onto the second face of the lens As there is no further object for the ray to hit ZEMAX draws it for a short distance and then stops tracing it Now click on the Source Ray object and press lt Shift gt lt right cursor gt to highlight the whole row Now press lt Cntl gt C to copy this object to the clipboard Click on the row again so it is no longer highlighted and press lt Cntl gt V to paste the object back into the Page 45 of 74 editor as a new ob
73. on tool as the foundation of your merit function construction Ultimately imaging systems are characterized by RMS spot radius or wavefront error and afocal systems by RMS angular radius or wavefront error The default merit function tool also automates the construction of the most common opto mechanical constraints designers require such as lens edge and center thickness constraints Additional goals and constraints can be easily added by inserting your own operands above the default merit function s operands in the editor ZEMAX writes out the dummy operand DMFS Default Merit Function Start to indicate where the default merit function starts and you should not hand edit the operands below this line Just click on the DMFS operand and press the insert key to insert new lines above the default merit function 4 9 4 Use Hammer Often The Hammer optimizer is used to improve a lens that has already been optimized by the local optimizer We recommend that in difficult files it be left to run overnight or over weekends if necessary 4 9 5 Use Adequate Boundary Conditions You should always add boundary constraints to your merit function as well as optical targets This yields two important benefits e ZEMAX will produce designs you can build and that meet your non optical goals For example you should always constrain edge and center thicknesses of lenses to be rea sonable and you can add constraints on length weight etc as required by y
74. optimization ZMX al 2 EEN Toners Configuration 1 of 1 In addition we also target the total power detected to be as large as possible This is an important constraint because if no rays land on the detector the RMS angular width is identically zero This is not a solution we want so we are optimizing for maximum received power and minimum angular width There are also some constraints on the shape of the pipe and you should consult the User s Manual description of the FREZ operand for full details Run the optimizer and select the Orthogonal Descent optimization operand This alternative local optimizer is very good at making big improvements quickly especially in non sequential systems although the Damped Least Squares optimizer can usually make further improvements on it Optimization Lo mea Targets 5 1 Cycle Variables 3 5 Cycles Initial Ment Function 13 121143146 10 Cycles Current Mert Function 13 121143146 50 Cycles Status Idle Inf Cycles Execution Time T Exit HCPU 4 I Auto Update After several cycles of optimization the lightpipe s shape has evolved to produce a peak luminous intensity of 73 Im sr which is over 200 times brighter than the starting design and an RMS angular radius of 9 I 3 Detector Viewer located at end of lightpipe 2 Update Settings Print Window Text Zoom Luminous Intensity al X coordinate value Optimization Example Detector 4 RCE Serfoce L
75. or The output light enters an homogenizing optical system that consists of two fly s eye lenslet arrays and a field lens The homogenizer is manufactured as a complete sub system which is then placed into the optical beam produced by the source and parabolic mirror 5 2 1 Object Positioning Note how the objects are referenced LI Non Sequential Component Editor o el Edit Solves Tools View Help Object Type Ref Object Inside Of X Positif A dd ame O A a of E a FC KEE A Cina Cema JR A g Csm AA A A A ejman msee OO o T g m _ e e p pps 2 a _ 3 A Every object has a number shown in the left most column of the editor and a Reference Object Ref Object 0 is the global coordinate reference point of the whole 3D space and objects 1 2 and 3 are positioned relative to this coordinate system Objects 4 5 6 and 7 are positioned relative to object 3 and they therefore are positioned like a sub assembly try moving object 3 and notice that objects 4 7 automatically move as well So the position of object 3 defines the position of the homogenizer assembly Note Any object can be positioned relative to any prior defined object which can be positioned relative to any other object defined prior to it etc Imagine we now want to move the homogenizer about some arbitrary point Click anywhere on object 1 and press the Insert key so that you now have a Null Object as
76. ordinates Field point 2 is likewise at 0 714 and field point 1 is at 0 0 Depending on the Analysis feature selected field points can be defined by either their field point number as entered in the Field dialog box or by their Hx Hy values 3 5 Defining amp Positioning Surfaces In sequential lens design light always starts at surface O the object surface and is traced to surface 1 then surface 2 then 3 etc It therefore makes sense to position surfaces relative to each other Returning to the double Gauss sample file look at the Lens Data Editor and click on surface 1 Note that this surface is drawn in red in the Layout plots when you click on it in the editor Rays propagate from left to right in the layout and this direction is the Z axis The Y axis goes from the bottom to the top of the window and the X axis goes into the screen If you position your right hand such that your middle finger is touching surface 1 in the layout window and points into the screen your index finger is pointing towards the right hand of the screen and your thumb is pointing upwards you have the classic right hand coordinate system used throughout ZEMAX and in most of the optical design literature Also observe that as you move your mouse over the layout window the coordinates of the mouse pointer are shown in the title bar of the window 1 Layout Z 3 031933 Y 16 278895 eo ate Pat W DOUBLE GA
77. our applica tion e Good boundary constraints speed up the global optimizers because ZEMAX does not look in regions of parameter space where the boundaries are violated This can speed up Global Search in particular by orders of magnitude 4 9 6 Use the System Check Utility The System Check utility under Reports System Check is an invaluable aid to ensuring there are no accidental errors in the system setup Although not every possible fault can be found by such a utility anything it does report should be checked and anything classed as an Error must be rectified Page 43 of 74 5 Non Sequential Ray Tracing EE only Note Even if you intend to use only the non sequential mode of ZEMAX you should work through the previous two chapters before starting this one Sequential and non sequential modes share many common user interface concepts and methods which are described in those chapters and are not repeated here Non sequential ray tracing is a powerful and general technology for tracing rays in systems where there are multiple optical paths Typical uses include e Illumination systems especially those with multiple or complex optical sources e Systems such as interferometers in which light that has travelled through several differ ent optical systems must be coherently recombined e Opto mechanical stray light analysis in otherwise sequential optical systems e LCD backlighting e Bio optical systems particularly those base
78. out blocking the beam You can specify the additional amount easily by adding a semi diameter margin in System General Misc 3 6 Working In Three Dimensions The double Gauss example lens is an axially symmetric lens and so each surface is simply positioned a distance in Z away from the previous surface But what about systems in which optical components are tilted or decentered with respect to each other Let s imagine that the second group of elements the doublet and singlet after the stop is tilted and decentered with respect to the first Click on surface 7 in the Lens Data Editor then hold the left mouse button down while dragging with the mouse to highlight surfaces 7 to 11 Alternatively click on surface 7 and press the Shift key while also pressing the down cursor key to highlight surfaces 7 11 Then click on Tools Coordinates Tilt Decenter Element and configure the dialog like so Tilt Decenter Element First Surface 7 Last Surface Decenter A Decenter Y Order Decenter then tilt Coordinate Break Color Default Color Coordinate Break Comment Tit Decenter the second lens group le Hide Trailing Dummy Surface OK After you press OK click on System Update All to update all the open windows Note that the Layout plot displays a warning Cannot perform 2D layout on non axial system Close this window and click on Analysis Layout 3D Layout or press the L3d button on the button bar Page 17 of 74
79. over all the operands in the merit function As the computed values of the operands move towards their target values the merit function value approaches zero Because the difference between the target and actual values of each operand is squared any deviation from the target value yields an increasingly positive value of the merit function MF Note The goal of the optimizer is to reduce the merit function to zero or as close as possible by adjusting the values of the variable parameters in the Lens Data Editor 4 5 Optimizing The Lens Now that we have defined the variables and the merit function click Tools Optimization Optimization or press the Opt button in the button bar and press the Automatic button Optimization Vanables Note that the optimizer is multi threaded and will split the calculation over all the CPUs in your machine if that will soeed the calculation up The merit function value quickly falls and the Spot Diagram plot shows the improved performance double click it to Page 34 of 74 make it update The RMS spot radius is now 11y on axis and about 20u at the 5 field point compared to 143u and 168u prior to the optimization That s a big improvement hl 2 Spot Diagram Update Settings Print Window Text Zoom Spot Diagram 10 733 18 812 LENS ZHX Ret Configuration 1 of 1 However there is a clear problem which can be seen in the Layout plot and Lens Data Edito
80. perating system _x86 for 32 bit operating system _x64 for 64 bit operating system The installation process may take some time as a number of Microsoft runtime files that are used by ZEMAX need to be downloaded and installed However if the necessary files have already been installed on your computer i e as a part of installing another software package then the installation of the RZ Prerequisites will be quite fast It is important that your computer remains connected to the internet during the installation process as the necessary Microsoft runtime files will be downloaded directly from the internet during installation Page 4 of 74 2 3 Installing ZEMAX The installation of ZEMAX itself is similarly straightforward Double click the ZEMAX installer once you have downloaded it and step through the on screen instructions You may choose where on your hard drive ZEMAX is installed 2 4 License Codes When ZEMAX runs for the first time it may prompt you to enter a license code If it does visit www zemax com updates and download the file Ic dat by right mouse clicking the link choosing Save Target As and storing in your ZEMAX installation folder over writing the current version If after that you continue to see a dialog box like so Version August 30 2011 Serial 23000 Engineering Edition Enter the license code for Version August 30 2011 Serial 23000 Engineering Edition below License Code Pe f you do not know th
81. perties of the common region are defined by whichever object is listed last in the Non Sequential Component Editor Open the sample file Non sequential Diffractives Diffraction grating lens with hole zmx This mixed sequential non sequential design shows a lens with diffractive power and a central region with no diffractive power 101 1 3D Layout Update Settings Print Window Text Zoom This is easily achieved by placing the non diffractive element after the diffractive element in the editor and co locating them There is no need to use the Inside Of flag when geometry objects are nested inside each other unless a source object is inside one of the nested objects Geometry objects may fully or partially overlap but source objects must always be entirely inside of any object they are co located with The Inside of flag must be used for all nested geometry objects as well as sources in this case 5 5 2 The Boolean Object Up to eight objects may be combined in any order by the Boolean object and Boolean objects may be combined with other objects including other Boolean objects For example a hexagonal lens can be formed by the Boolean intersection of a lens and a hexagonal bar I 3 NSC Shaded Model Update Settings Print Window Tet Zoom Spin See any of the sample files in Non sequential Geometry Creation for further examples Page 56 of 74 5 5 3 The Array Object The Array object allows you to make one two
82. positioned relative to object 1 while retaining its absolute position and orientation in global coordinates In other words object 4 has not moved but its position is now defined relative to a different object The subsequent objects are still positioned relative to object 4 hI Non Sequential Component Editor Edit Solves Tools View Help Object Type Comment Ref Object Inside Of X Positi If you now apply a Tilt About X of 10 degrees to object 1 you will see that the whole homogenizer assembly pivots about object 1 but the lamp assembly remains in place I 4 NSC 3D Layout Update Settings Print Window Tet Zoom 5 2 2 Object Parameters As well as being positioned objects are given their defining parameters in the NSC Editor For example the Lenslet 2 object is defined by parameters like x and y halfwidths thickness radii of curvature and conic constant and numbers of lenslets in x and y Page 49 of 74 There is a great advantage to this parametric approach Parametric objects require relatively little memory are fast to ray trace and can be changed easily They are also optimizable just like sequential surfaces Further interrelationships between objects can be easily defined via pickup solves Note that the second lenslet object uses pickups on several parameters to lock itself to the first lenslet object This is a great advantage during optimization as changes to one parameter can automatically flow through the w
83. ppress Frame T Fetch Rays Split NSC Rays Eu marion Page 24 of 74 2 3D Layout Update Settings Print Window Text Zoom Finally click on Analysis Spot Diagrams Configuration Matrix to see how the spot varies with scan angle 3 Configuration Matrix Spot Diagram Update Settings Print Window Text Zoom 0 0000 0 0000 bey Configuration Matrix Spot Diagram 32481 POX Uni TEMPSTOR ZMX Configuration All 5 3 8 Exporting To Mechanical CAD Packages At some point in your lens design you may want to export the lens design into a mechanical design package so that you or your mechanical engineering colleagues can design lens mounts and other opto mechanical components alongside the lenses and rays This is easily achieved via Tools Export Data Export IGES STEP SAT STL Solid Set it up like so Export IGES STEP SAT STL Solid Data File First Surface Last Surface Tolerance 1 00E 4 if Delete Vignetted Export Dummy Surfaces i Surfaces As Solids Split NSC Rays Scatter NSC Rays Use Polarization carcel tp Page 25 of 74 And load the file produced into your 3D CAD package A qa TrarnchAamic Ve ITIUEARAORK i kK Toy x ATFEansSiMiddQIC AG CMF SOMBRE Gl j is Pe Ca A A nd o al I if File Edit Tools View Selection Geometry Window Help X Dasg Frou 196960 est 9000 m M9 a ha Aa Aal Y A A Ael Note If you are using SolidWorks and do not
84. pressed Full Data Filter Idle Note that the ray trace takes longer now because of the time taken to write one million ray histories out to disk Then press Analysis Ray Tracing Ray Database Viewer or press the Rdb button The Ray Database Viewer shows the history of every ray traced Page 53 of 74 Ray Database Viewer simple LXHL B0001 LED model RD i Show Unprocessed Data Expand Into Branches W XYZ LMN Normal Path Egz First Ray 1 Last Ray Apply Filter ee Save Subset Data As IO uuu ZRD Format Retain Input File Format Save Rays On Object o o As CO Cancel Save Load Help The intensity position direction cosines normals path length and polarization data of every ray can be shown although only intensity is shown here The ray is broken down into segments where each segment is a single ray object intersection Segment 0 is the ray data at the source Various parameters XRTS etc show what happened at the end of the segment X terminated R reflected etc This example is very simple in that rays are launched traced once and terminated Seg Prnt Levl In Hit Face XRTS DGEF BZ Intensity Comment 0 0 0 0 0 ae ae 123272260455 007 Source 1 LXHL BDO1 il 0 1 0 2 gt a Le 32722604 56 007 In a more realistic system there are many more segments of course Load the sample file led_model zmx in the same folder as the file we are currently using trace Analysis rays using these setti
85. r l 1 Layout f a Update Settings Print Window Tet Zoom Total Axial Length 279 22604 om LENS IMK Configuration 1 of 1 The lens is unfeasibly thick We have told ZEMAX to minimize the RMS spot radius but have given it no guidance about any constraints it must operate within Press the F3 button or click on Editors Undo This will undo the optimization and restore the previous unoptimized system Return to the Merit Function Editor and click on Tools Default Merit Function again and configure it like so Page 35 of 74 Default Merit Function Optimization Function and Reference Centroid C Rectangular Aray 4x4 Max Edge 2 Max 11000 Edge 0 5 lv Assume Axial Symmetry Start At 2 Ignore Lateral Color Relative X Weight 0000 Configuration All Overall Weight 1 0000 Cancel Save Load Reset Hel These settings require that the lens elements have a center thickness somewhere in the range between 2 and 20 mm and that the lens edge thickness be greater than 2 mm this is a useful constraint to aid manufacturability Any surfaces made of air must have thicknesses between 0 5 and 1000 mm which is not necessary in this design but in a multi element design will prevent lens elements from hitting each other or being unreasonably far away from each other and is therefore added here for completeness If we repeat the optimization and use Automatic again we get Ul Optimizati
86. r at the bottom 2 An editor spreadsheet in this case the Lens Data Editor Almost all data is entered via editors which allow the parameters that define the optical system to be easily seen and linked together or optimized as required Data that is rarely modified once set is entered elsewhere as we will discuss later For now note that the Lens Data Editor shows a sequence of Standard surfaces which have radius of curvature thickness glass type Semi diameter and conic constant There are then a series of parameters labeled O through 12 which are not used by this surface type and finally a Thermal Coefficient of Expansion TCE column and a coating column for EE use only Each surface in this lens has coating AR which is a quarter wave thick MgF2 coating 3 Analysis windows which are the results of some calculation the program has performed In this case the 2 D Layout RMS Wavefront error versus field plot and Spot Diagram are shown Before proceeding click on Tools Miscellaneous Performance Test and click Run Test Performance Test Test results are only for comparing computers running the same EMAX version and lens file 3 61 million rays per second 43 31 million ray surfaces per second 17 50 thousand system updates per second HCPU EM Close Run Test a This will give you a simple metric of how fast ZEMAX is on your computer It also shows one of the best features of ZEMAX its ability
87. ram Files ZEMAX and locate a file called snt lconfig xml bak Rename this file to sntlconfig xml and open it in Notepad Edit the following line lt Contactserver gt LOL Oi ll lt ContactServer gt Replace the default entry 10 0 0 1 with the IP address of your keyserver machine and save the file Page 5 of 74 2 6 Troubleshooting ZEMAX will run without problem in the vast majority of cases lf you do experience problems then visit our Knowledge Base at www zemax com kb Look at the Category Installation and Troubleshooting for help Make sure your key is plugged in 2 7 Customizing Your ZEMAX Installation When ZEMAX starts for the first time it loads a number of default settings which you may prefer to customize to your preference Start ZEMAX and click on File Preferences A multi tab dialog box will open Preferences Colors 1324 Buttons 1 16 Buttons 1732 Buttons 33 48 Address Folders Graphics Miscellaneous Editors Printing Status Bar Colors 1 12 Address Line 1 Address Line 2 Address Line 3 Address Line 4 Address Line 5 Show Line 4 As File Name Hide Address This allows you to set all the installation specific settings Note Full details of all Preference settings are given in the User s Manual chapter 4 File Menu or can be obtained by pressing the Help button in the dialog boxes You should explore all these tabs but the most important ones are
88. rrations up to order r In the doublet lens we designed we used 4 rings and therefore could con trol all aberrations up to r which is a higher order than fifth order aberrations can achieve See G W Forbes Optical system assessment for design numerical ray trac ing in the Gaussian pupil J Opt Soc Am A Vol 5 No 11 p 1943 1988 for a very readable and full account of this useful technique e We are usually interested in optimizing for real world performance metrics like spot size wavefront error MTF etc Fifty years ago aberration theory was a useful computational shortcut but 21 century computers and multi threaded software like ZEMAX are mas sively faster than the tools available then Optimizing directly for the desired performance is more practical than optimizing for some intermediate function that we hope will then go on to give us the desired performance Optimize for what you want to test the built sys tem for Note for example that in the optimization of the doublet we did not need to target chromatic effects like axial or lateral color directly the default RMS spot radius merit function provided this automatically The exception to this is distortion because distortion affects only the location of the image not its quality Operands like DIMX DISG etc can be used to control distortion Page 42 of 74 4 9 3 Use the Default Merit Function Tool We recommend that you use the default merit functi
89. s are available A multi computer network key is also available You must install both programs under a user account with Administrator privileges Only Standard User privileges are needed to use ZEMAX once installation is complete Note The key supplied with the ZEMAX software is worth the full purchase price of the software If the key is lost or stolen it will not be replaced without payment of the full purchase price Insure the key as you would any other business or personal asset of comparable value 2 1 Installing The Key Driver The key driver installation is straightforward Double click the key driver installer once you have downloaded it and choose the Complete installation of all program features A dialog box will also ask for your permission to modify the firewall settings of your computer to allow remote users of your computer to run ZEMAX using Remote Desktop If you want to authorize this click Yes otherwise click No To change this setting just re run the key driver installer Plug the key in once the key driver installation is complete and Windows will detect the hardware key The green LED at the end of the key will illuminate 2 2 Installing RZ Prerequisites The installation of the RZ Prerequisites package is also straightforward Double click the RZ Prerequisites installer once you have downloaded it and step through the on screen instructions The appropriate installer to download will depend on your o
90. set to be Coordinate Breaks with the appropriate tilt angles The second tilt angle is set as a pickup from the first tilt angle Finally all subsequent surface thicknesses and curvatures change sign to account for the new mirror Remember that light normally propagates in Z left to right but after a mirror it obviously goes in the other direction Using the Add Fold Mirror Delete Fold Mirror tools automates all the tedious sign conversions We now want to scan this mirror through 10 We will initially tilt it through 10 and then use multiple configurations to define multiple tilt angles Click on surface 4 which is the mirror surface now Click on Tools Coordinates Tilt Decenter Element and configure the dialog like so Page 21 of 74 Tilt Decenter Element First Surface 14 Decenter X 0 0 Decenter Y 0 0 Order Decenter then tilt Coordinate Break Color Color 4 Coordinate Break Comment Mirror Tit i Hide Trailing Dummy Surface cancel 101 2 3D Layout Update Settings Print Window Text Zoom Note that the semi diameter of the Image surface has been set manually as indicated by the U for user defined status flag in the Lens Data Editor Click on this semi diameter and enter a semi diameter value of 12mm 121 2 3D Layout Update Settings Print Window Text Zoom The Tilt Decenter Element tool has operated just as it did in the earlier double Gauss example and it has added two more Coordinat
91. sources like the Source Diode or Source Filament in which the source radi ance is computed from some equation and you enter the parameters for this equation via the editor e Measured sources like the Source IESNA Source EULUMDAT and Source File Note that IESNA and EULUMDAT data files contain only far field angular data and model the source as a Spatial point The DAT and SDF formats used by the Source file object contain both spatial and angular ray data and so define the full radiance of the source Data in these formats are provided free by many LED and lamp manufacturers and can also be exported by third party programs like Radiant Imaging s ProSource and Opsira s Luca Raymaker The DAT and SDF formats are documented in the Users manual in both ASCII and binary formats The difference between the two formats is that the SDF format contains spectral wavelength data whereas the DAT format does not Source wavelengths are defined in the System Wavelength dialog just like sequential systems although other definitions are also available and will be discussed later in the section on Colorimetry Source Units Watts or Lumens are chosen under the general dialog box in the Units tab Sources are positioned in global coordinates in exactly the same way as any other object All sources use parameters 1 5 of the Non Sequential Component Editor to define some basic information about the source These are e Layout Rays D
92. the thickness of this surface is controlled by a marginal ray height solve and can be seen by the M following the thickness This keeps the lens at paraxial focus We will discuss solves more in the next chapter For now simply press Insert after clicking on surface 2 to insert a new surface Give this surface a thickness of 70 mm and note that the thickness of the last surface automatically changes to keep this lens in focus i 1 Layout Update Settings Print Window Tet Zoom Total Axial Length 101 46538 mm Page 20 of 74 Lens Data Editor Edit Solves View Help seman A tain y af IEEE ION IEC e Em e ne We will now make surface 3 a Fold Mirror which just reflects the light through some angle Click on surface 3 and then click Tools Coordinates Add Fold Mirror and configure it like so idd Fold Minor Fold Surface Tit Type x Tit Reflect Angle 90 0 caret When you press OK the 2D layout window will again show Cannot perform 2D layout on non axial system Close this window and open a 3D layout You will have 10 2 3D Layout o O fame Update Settings Print Window Text Zoom This feature inserts two dummy surfaces one before and one after the selected fold surface The fold surface then has its glass type set to MIRROR which is a special status that tells ZEMAX that light should now propagate in the opposite direction The two newly inserted adjacent surfaces are
93. the various aspects of the lens system s performance Analysis windows all operate with the same user interface e Pressing the Update menu item or double clicking anywhere in the Analysis window with the left mouse button will make the Analysis window recompute e Pressing the Text menu item will show the underlying data that is being presented graphically e The Window menu item gives you access to Copy Export as Bitmap Export as Text File etc options 111 2 RMS vs Field o nea Update Settings Print Window Ted Zoom A typical Analysis window is shown opposite All Analysis wndows share the same menu bar You can zoom in on a section of interest by clicking the left mouse button holding it down and dragging it over the region you wish to zoom in on DOUBLE GAUSS Poly 0 486 0 588 0 656 Double Gauss 28 degree field zm Reference Centroid Configuration 1 of 1 Clicking the Settings menu item or right mouse clicking anywhere in the Analysis window will bring up the Settings dialog box RMS Diagram Settings Ray Density Wavelength Field Density 0 Data Plot Scale Refer To Method Gauss Quad Orientation Use Dashes Show Diffraction Limit Use Polarization if Remove Vignetting Factors sae Cancel Save Load Reset Help The layout of this box will depend on the Analysis feature used of course The Settings are used to control the calculation Pressing OK will r
94. tilt decentration of the first CB Also its order flag is not zero so it executes right to left This means that the second CB undoes the first CB and restores the coordinate system to its original frame of reference Note also the letter P next to the decenters and tilts of the second CB This indicates that a Pick Up Solve has been placed on this parameter Click on the Decenter Y parameter of the second CB and double click it with the left mouse button Parameter 2 solve on surface 13 Solve Type From Surface 7 Scale Factor This locks the value of parameter 2 on surface 13 to be whatever the value of parameter 2 surface 7 is except the sign is the opposite The pick up solve is one of the Editor s most useful features as it allows one part of an optical system to be locked to another Page 18 of 74 Note If you visit the ZEMAX User s Knowledge Base at www zemax com kb look at the category Sequential Ray Tracing 3D Geometries for many helpful articles about the use of Coordinate Break surfaces Finally click on Analysis Layout Shaded Model to get a presentation quality graphical representation of the lens Most engineering work is done with the 2D and 3D layouts but most presentations of results are done with the Shaded Model because it yields prettier pictures Note that this window also allows you to spin the Shaded Model with the mouse To see this move the mouse over the Shaded Model window and
95. to use multiple CPUs in your computer if available Calculations are split up and spread over all available CPUs and the results stitched back together again without any user interaction 3 1 The Lens Data Editor In sequential ray tracing light is traced from its source called the Object surface to surface 1 then to surface 2 3 etc until it lands on the final Image surface For historical reasons this surface is always called the Image surface even though the optical system may not form an image of the source A laser beam expander or eyepiece for example may be afocal this is covered later Surfaces are inserted or deleted in the editor using the Insert or Delete keyboard keys or via the Edit menu which also allows individual cells or the entire spreadsheet to be copied to the clipboard Column widths can be varied by placing the cursor in the top row over the column separator When the cursor turns to a gt symbol click and hold the left mouse button to resize the column Columns and rows can be hidden entirely and unhidden using the View menu Page 8 of 74 The V next to some parameters means that this parameter is variable ZEMAX is allowed to change the values in such cells in order to improve the performance This will be discussed in more detail later ih Lens Data Editor Edit Solves View Help Surfaces also have a set of properties that are not directly visible in the editor These ar
96. ull 3D volumes not a collection of individual surfaces Insert Lens There are three basic types of object e Source objects from which rays are launched into the non sequential system Page 44 of 74 e Geometry objects which define the optical components lenses prisms mirrors CAD objects etc that the rays reflect refract scatter or diffract from e Detector objects which detect rays and give quantitative data of optical performance like irradiance radiant intensity etc Note See Chapters 13 14 and 15 of the User s Manual for full details of all the object types ZEMAX supports Double click on the Object Type of object 1 in the editor You will get a multi tab Object Properties dialog similar to the Surface Properties dialog in the Lens Data Editor Set the Object Type to Standard Lens which is a common type of geometry object Object 1 Properties Ea I 1 NSC 3D Layout f fa ae Update Settings Print Window Text Zoom Diffraction Sources Draw Birefringence Type Coat Scatter ScatterTo Face Bulk Scatter Gradient index Type Standard Lens p Data File m Click OK to close the dialog Open a Layout plot to i see the object Note that you have a single Standard 01 1 NSC 3D Layout colo Lens object that defines the entire object rather than Update Settings Print Window Text two surfaces and a thickness Looking at the editor Zoom you can positi
97. vely work with you to obtain the best possible system performance Note Even if you intend to use only the non sequential mode of ZEMAX you should work through this example as the concepts of optimization are the same in non sequential ray tracing as in sequential Optimization is a three step process e First a basic lens design is entered which has the correct field of view wavelength system aperture number of surfaces etc This system should be traceable without error e Next some parameters in the Editor are defined as variables This means that ZEMAX can change the value of these variable parameters in order to better meet the design specification e Last the design specification is expressed as a series of design goals called a merit function The merit function ultimately is expressed as a single number and the closer to zero this number is the closer the design is to your desired performance Optimization then changes the values of the defined variable parameters so that the merit function is reduced to its minimum value ZEMAX contains several different optimization algorithms two local optimizers and two global optimizers In this example we will use the Damped Least Squares local optimizer and the Hammer global optimizer Also this three step optimization process may be repeated several times during the design process After optimization the system performance may still not be as required and more lenses may be need
98. we show the blue and yellow sources as being separate and also as overlapping 1 NSC Shaded Model Update Settings Print Window Tet Zoom Page 61 of 74 i 2 Detector iene Update Settings Print Window Text Zoom Detector Image Irradiance Two color mizing gives white Detector 5 NSCG Surface 1 Size 20 000 WA 20 000 H Millimeters Pixels 501 Wz 501 H Total Hits 3999917 Peak Tlluminance 397E 001 lumens mm 2 Total Power 1 382E 003 lumens Note that because the two beams do not overlap perfectly you can see a blue tinge on one side of the white spot and a yellow tinge on the other Optimization operands allow each pixel s color to be analyzed and targeted in the merit function so that you can optimize for a desired color Page 62 of 74 6 Polarization Coatings amp Scattering EE Only Ray tracing programs generally treat rays as purely geometric entities which have only a position orientation and phase For example a ray is completely described at a surface by the ray intercept coordinates the direction cosines which define the angles the ray makes with respect to the local coordinate axes and the phase which determines the optical path length or difference along the ray At the boundary between two media such as glass and air refraction occurs according to Snell s law Usually the effects at the interface which do not affect beam direction are ignored These effects include amplitude and ph

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