Optical Design with Zemax for PhD - Advanced

Transcription

1 Optical Design with Zemax for PhD - Advanced Seminar 9 : Advanced Topics Herbert Gross Winter term

2 2 Preliminary Schedule No Date Subject Detailed content Repetition Correction, handling, multi-configuration Illumination I Simple illumination problems Illumination II Non-sequential raytrace Physical modeling I Gaussian beams, physical propagation Physical modeling II Polarization Physical modeling III Coatings Physical modeling IV Scattering Tolerancing I Sensitivity, practical procedure Tolerancing II Adjustment, thermal loading, ghosts Additional topics Adaptive optics, stock lens matching, index fit, Macro language, coupling Zemax-Matlab

3 3 Content 1. Index fit 2. Stock lens matching 3. Macro programming 4. Coupling Zemax-Matlab 5. Misc

4 Glasses in Zemax For optimization Definition of a glass as a variable point in the glass map model glass Establish own glass catalogs with additional glasses preferred choices as an individual library Ref.: B. Böhme 4

5 Material Index Fit choice of 4 dispersion formula after fit: - pv and rms of approximation visible - no individual errors seen check results for suitable accuracy, especially at wavelengths and temperatures with sparse input data and at intervall edges add to catalog enter additional data Save catalog Ref.: B. Böhme 5

6 6 Material Index Fit Establishing a special own material Select menue: Tools / Catalogs / Glass catalogs Options: 1. Fit index data 2. Fit melt data Input of data for wavelengths and indices It is possible to establish own material catalogs with additional glasses as an individual library

7 7 Material Index Fit Melt data: - for small differences of real materials - no advantage for new materials Menue option: Glass Fitting Tool don t works (data input?)

8 8 Material Index Fit Menue: Fit Index Data Input of data: 2 options: 1. explicite entering wavelengths and indices 2. load file xxx.dat with two columns: wavelength in mm and index Choice of 4 different dispersion formulas After fit: - pv and rms of approximation visible - no individual errors seen - new material can be added to catalog - data input can be saved to file

9 Stock Lens Matching This tool swaps out lenses in a design to the nearest equivalent candidate out of a vendor catalogue It works together with the merit function requirements (with constraints) Aspheric, GRIN and toroidal surfaces not supported; only spherical Works for single lenses and achromates Compensation due to thickness adjustments is optional Reverting a lens to optimize (?) Top results are listed Combination of best single lens substitutions is possible. Overall optimization with nonlinear interaction? Ref.: D. Lokanathan

10 Stock Lens Matching Selectioin of some vendors by CNTR SHIFT marking Ref.: D. Lokanathan

11 Stock Lens Matching Output Ref.: D. Lokanathan

12 12 Macro Language There is a macro language for Zemax to allow for individual problem solving Some provided example files are distributed Editing and running can be done from Zemax interface Necessary: xxx.zmx-file Debugging of macro-language errors is cumbersome Not all of the output data is provided by the commands Coding of parameters is in many cases a bit tricky Graphical options rather limited Possibilities: 1. special and individual analysis 2. change of system data and case studies 3. optimization 4. print export of data

13 13 Macro Language Code Example: Incidence angles at all surfaces for 3 field positions Online output

14 14 Important Macro Commands comment line follows variables, declarations, simple operations, strings, basic mathematical functions IF THEN ELSE, GOTO, LABEL, FOR NEXT a = AQVAL() numerical aperture ro = CURV(j) surface curvature of surface no. j y = FLDY(j) field size no. j u = RAYL(j) direction cosine of real ray at surface no. j y = RAYY(j) y-value of real ray at surface no. j t = THIC(j) thickness at surface j PRINT text, x,y print text FORMAT 5.3 numerical format of output: 5 places, 3 digits OUTPUT fname.txt declaration of output file for results GETSYSTEMDATA n get special coded (n) data of the system GETZERNIKE maxorder, wave, field, sampling, vector, zerntype, epsilon, reference PWAV n set primary wavelength RAYTRACE hx, hy, px, py, wavelength SURP surface, code, value1, value2 set surface properties SYSP code, value1, value2 set system properties

15 15 Macro Example 1 Calculate Focal lengths of all lenses get number of surfaces Ns Ns = nsur() declare N, double, 1, Ns+1 get refractive indices FOR j = 1,Ns+1,1 N(j) = indx(j-1) next number of lenses Nl = 0 for j=1,ns+1,1 if ( N(j) > 1 ) then Nl = Nl + 1 next header line: number of surfaces and glasses print " " format 2.0 print "lenses ",Nl focal lengths print "focal lengths " print " " print result k=0 for j = 1,Ns-1,1 if ( N(j) == 1 ) then goto 1 k = k+1 c1 = curv(j-1) c2 = curv(j) t = thic(j-1) ni = N(j) F = (ni-1)*(c1-c2) + (ni-1)*(ni-1)/ni*t*c1*c2 foc = 0 if (F = 0) then foc = 1/F format 2.0 print "L ",k," (",j-1,"-",j,") f = ", format 10.4 print foc label 1 next

16 16 Macro Example 2 Calculate telecentricity error sampling number over field nfield = 21 Set primary wavelength jwave = pwav() define considered field index jfield = 2 save old field heigth hyold = FLDY(jfield) calculate field increment dw = 1/(nfield-1) fix ray data in pupil and x-field hx = 0 px = 0 py = 0 define surface of evaluation n = nsur() header line print " w-rel w-abs ws" raytrace of chief rays for all field heights and print results FOR j = 1,nfield,1 hy = (j-1) * dw hyabs = (j-1) * dw * hyold SYSP 103, jfield, hy update raytrace hx, hy, px, py, jwave delw = raym(n) FORMAT 10.5 PRINT hy, hyabs, delw NEXT recover data SYSP 103, jfield, hyold

17 17 Macro Example 3 Calculate absolute size of Zernike for astigmatism and coma Optional Output-File OUTPUT "c:\gross\new\zernvswave.txt" Number of points in the wavelength grid jfield = 2 jwave = 1 1 = 32, 2 = 64 Sampling Pupille sampl = 2 maxzern = 9 Set primary wavelength wold = wavl(1) calculate Zernikes GETZERNIKE maxzern,jwave, 1,sampl,1, 0 ast = sqrt( vec1(8+5)*vec1(8+5) + vec1(8+6)*vec1(8+6) ) coma = sqrt( vec1(8+7)*vec1(8+7) + vec1(8+8)*vec1(8+8) ) print result print " " FORMAT 10.5 PRINT "astig : ", ast print "coma : ", coma

18 18 Matlab Coupling with MZDDE Calling Zemax as Raytrace-engine from Matlab Freeware MZDDE (Mathworks File Exchange) allows coupling of Matlab with Zemax Zemax DDE server toolbox Zemax must be opened Debugging is complicated Problems with timeout, refreshing and updating of data, especially under 64 bit windows

19 19 Matlab Coupling with MZDDE Collection of Matlab-routines zset, zget,... Well documented library of routines

20 20 DLL Links User defined surfaces are possible A routine written in C or C++ must be provided as DLL By linking the DLL, the raytrace can be performed through user defined surfaces Debugging of wrong DLL s is cumbersome, there is limited support from the hotline Runtime is quite fast Best way to establish a DLL due to the specific interface: modify a provided C-source-routine