Optimization Tutorial Using OSLO Standard or Premium

Transcription

1 Page 1 f 18 Optimizatin Tutrial Using OSLO Standard r Premium Optimizatin Tutrial Using OSLO Standard r Premium Lambda Research Crpratin INTRODUCTION Nte: Parts f this tutrial are very similar t the "Optimizatin Tutrial Using OSLO Light." This has t be the case in rder fr each tutrial t stand n its wn. If yu are reading bth tutrials, please be aware that steps #1 thrugh #16 are exactly the same and culd be skipped in ne f the tutrials. Optimizatin is the prcess by which the perfrmance f a lens system is imprved by changing the values f sme f the lens data (variables) such that a measure f lens perfrmance is imprved. This measure f lens perfrmance cmes in the frm f an errr functin r merit functin. An errr functin is a list f targets that OSLO tries t minimize during ptimizatin (when the errr functin is minimized the lens is imprved). When the ttal value f the errr functin is as small as it can be, then the system has been fully ptimized and is as gd as it can be. If the targets (perands) that make up the errr functin are nt exactly zer then the errr functin has sme residual errr assciated with it. Since the errr functin is the cmpsite f the individual targets, in a way it is a measure f the cmpsite errr f the system - hence the name errr functin. This tutrial will cnsist f perfrming additinal ptimizatin n a lens design frm called the "Cke" triplet. As a histrical nte, the name f the lens design frm cmes frm the Cke cmpany which was invlved in the initial inventin f the Cke triplet design frm. The exact prescriptin f the lens that we will use (the surface curvatures, glasses and thicknesses) is an adaptatin f a design dne by R. Kinglsake and included in his bk "Lens Design Fundamentals," pp , (Acadmeic Press 1978, ISBN ). The Cke triplet design frm has been used in millins f lw cst cameras, prjectrs, and varius ther instruments. We will be using the Cke Triplet as the starting pint f ur ptimizatin. Lenses like the Cke triplet are typically designed fr film cameras. The Cke triplet lens prescriptin supplied with OSLO has a 50mm fcal length, which suits the 24x36mm frmat used fr 35mm cameras. The lens is nt ptimum fr a typical digital camera, which has a smaller image size, because the fcal length is t lng. In this example we will redesign the lens t have a fcal length f 10mm which is mre suited t cntemprary digital cameras. In additin, we will make the lens faster (re-design the lens t a lwer f/number) s that the paraxial specificatins becme 10mm EFL, f/2.8 and +/-20 degrees field angle. The steps in this tutrial are as fllws: Lens Entry - Create a starting lens that will be used fr bth ptimizatin appraches in this tutrial. Open the "demtrip.len" lens file. OUTLINE Scale the entire lens t an effective fcal length (EFL) f 10mm. Change the Entrance Beam Radius s that the system nw has an F-number f f/2.8. Change the apertures radius f all the surfaces t 1.8 s that the larger beam can get thrugh. Increase the thickness f the first and third lens elements t 0.7mm. Increase the thickness f the center lens element t 0.3mm. Apply a slve n the curvature f surface 6 s that the system EFL f 10 is maintained. As sn as yu have applied the slve, remve the slve nce again s that the EFL is nt cntinually updated. Set variables that vary all curvatures and all air spaces. Update the title f the lens and save the lens as "Triplet10mm_Start.len" in yur private directry.

2 Page 2 f 18 Optimizatin Tutrial Using OSLO Standard r Premium Optimizatin using the GENII Errr Functin Perfrm the Ray Intercept Curves (RIC) Reprt Graphic analysis as a baseline analysis f current system perfrmance. Lck the graphic windw against inadvertent updating. Generate the GENII Ray Aberratin Errr Functin perands. Save the lens as "Triplet10mm_OptGeniiStd.len" in yur private directry. Optimize the lens system. Perfrm the RIC Reprt Graphic analysis in a new graphic windw t cmpare with the baseline analysis. Lck the graphic windw against inadvertent updating. Save the lens with the same "Triplet10mm_OptGeniiStd.len" file name. Optimizatin using the OSLO Spt Size / Wavefrnt Errr Functin Lens entry Restre "Triplet10mm_Start.len" frm yur private directry. Generate the OSLO Spt Size / Wavefrnt Errr Functin perands. Crrect clr using Cnrady's D-D methd. Cntrl distrtin t <0.5%. Keep ther defaults. Save the lens as "Triplet10mm_OptOSLO_SS.len" in yur private directry. Optimize the lens system. Perfrm the RIC Reprt Graphic analysis in a new graphic windw t cmpare with the baseline analysis. Lck the graphic windw against inadvertent updating. Save the lens with the same "Triplet10mm_OptOSLO _SS.len" file name. DETAIL 1) Open the lens file lcated at " \public\len\dem\lt\demtrip.len". 2) If it is nt already pen, pen the surface data spreadsheet by chsing "Len>>Surface Data Spreadsheet" frm the OSLO menu.

3 Page 3 f 18 Optimizatin Tutrial Using OSLO Standard r Premium If yu have a lens that is a gd starting pint except fr its fcal length, it is usually nt a wise idea t frce the lens t the new fcal length thrugh ptimizatin.. Instead, it is better t simply scale the entire lens t the new fcal length - f curse this will als scale apertures, curvatures and thicknesses as well. 3) Right click the muse in any white cell f the surface data spreadsheet and chse "Scale Lens>>Scale Lens t New Fcal Length " frm the resulting pp-up menu and scale the lens t a fcal length f 10. Nte: The current system has an f/number f 4.0. T achieve an f/number f 2.8 yu need t increase the system aperture by 4.0/2.8 4) Nte that the almst all the parameters f the lens prescriptin have been changed. The entrance beam radius is nw Change the Entrance Beam Radius value t t frce the system t have an F-number f f/2.8. 5) The F-number f the system can nw be verified by chsing t list Paraxial Cnstants (Pxc) frm the Text Windw tlbar. If yu are having truble finding this buttn r yu want t learn mre abut this buttn, please refer t Sideline #1 at the end f this tutrial. 6) Ntice that the apertures in the Aperture Radius clumn are all smaller than the Entrance Beam Radius just defined. Change the apertures f all the surfaces t 1.8 s that the larger beam can get thrugh.

4 Page 4 f 18 Optimizatin Tutrial Using OSLO Standard r Premium 7) Nte that with the scaled lens the elements are t thin t supprt an aperture f 1.8. Increase the thickness f the frnt and back elements frm ~0.40mm t 0.7 mm, and the thickness f the center element frm ~0.2mm t 0.3mm. Nw the n-axis beam can get thrugh the lens system, but the fcal length is n lnger exactly 10mm because the thicknesses have been changed. T fix the fcal length, we will apply a "slve" t the last refractive surface (surface 6). A "slve" adjusts a system parameter s that sme cnditin is met. We will apply an "axial ray angle slve" which frces the surface curvature f surface 6 t be adjusted s that the angle f the axial ray leaving surface 6 is maintained at a certain value. With an entrance beam radius f mm, the fcal length f 10mm will be achieved with an axial ray angle slve f (radians). 8) T access the axial ray slve, click n the grey buttn n the right side f the radius clumn n surface 6 and chse "Slves(S)>>Axial Ray Angle " frm the resulting pp-up menu. Enter fr the value f the slve.

5 Page 5 f 18 Optimizatin Tutrial Using OSLO Standard r Premium 9) Nte that the system fcal length is nw 10mm as desired. Observe the "Efl" cell in the upper right crner f the surface spreadsheet r chse "Pxc" frm the Text Windw fr analysis. 10) As sn as yu have applied the slve, remve it again by chsing "Direct Specificatin" frm the same ppup menu. The letter "S" in the grey buttn f the "Radius" clumn will disappear, but the surface curvature will still be set t the value that causes the fcal length t be 10mm. The surface curvature can nw be used later as a variable during ptimizatin (system parameters such as a surface curvature cannt have a slve applied at the same time it is being used as a variable during ptimizatin). If yu are cnfused abut the usage f the terms "Radius" and "Curvature" when describing a surface in a lens system, be aware that a surface "curvature" (cv) is the inverse f a surface "radius" (rd). Tthey bth refer t the same prperty and are mathematically related because cv=1/rd. Nte the secnd clumn f the Surface Data Spreadsheet lists the surface radius by default. Hwever when peple discuss an ptical design, they usually refer t surface "curvature" s that there is n cnfusin between surface radius and aperture radius (which is the item listed in the 4 th clumn f the surface data spreadsheet). 11) Change the title f the lens t "Dem Triplet 10mm f/2.8 20deg" in the upper left crner f the surface spreadsheet windw (next t the "Lens:" designatin), and save the file as "Triplet10mm_Start.len" in yur " \private\len" directry. Nw that yu have the starting design set fr ur ptimizatin, the next step is t set sme system parameters t be variables. Eventually we want t set all 6 surface curvatures t be variables.

6 Page 6 f 18 Optimizatin Tutrial Using OSLO Standard r Premium 12) T set the first surface curvature as a variable, click n the grey buttn n the right side f the "Radius" clumn fr surface #1, and chse "Variable (V)" frm the resulting pp-up dialg. A letter "V" will appear in the grey buttn when yu are dne Yu can cntinue ding this fr all surfaces, r yu can set all surface curvatures as variables all at nce. OSLO allws yu t manage the variables in yur ptical system tgether as a grup: 13) Open up the Variables Data Editr by clicking n the "Variables" buttn near the tp f the Surface Data Spreadsheet. Then click n the "Vary All Curvatures" buttn in the resulting dialg. This adds all the remaining surface curvatures t the variable list in the "Variables Data Editr". 14) We als want t vary all the air spaces in ur design (just the thicknesses between the lenses - nt the thickness f the lenses themselves). We d this by clicking n the "Vary All Air Spaces" buttn in the "Variables Data Editr." 15) Click n the green check mark in the upper left crner f the "Variables Data Editr" t accept yur changes and clse ut f this spreadsheet, but d nt clse the Surface Data Spreadsheet. 16) Befre mving n, re-save the lens system by chsing "File>>SaveLens" frm the OSLO menu r click n the flppy disk icn ( ) frm the main OSLO windw tlbar. Nw that a starting lens system and variables have been defined, we need t specify an errr functin t cntrl the ptimizatin. Rather than generating an errr functin frm scratch, OSLO allws yu t chse frm a cuple f default errr functins. In mst cases yu can use the default errr functins with little mdificatin, but keep in mind that in OSLO yu can always manually mdify an errr functin t fit yur particular requirements. In this tutrial we will take a lk at generating tw different types f default errr functins.

7 Page 7 f 18 Optimizatin Tutrial Using OSLO Standard r Premium Optimizatin using the GENII Errr Functin: The GENII (prnunced jean-ee ) errr functin is based n the default errr functin f the frmer GENII ptical design prgram. Sme features f the GENII prgram have since been incrprated int OSLO. The GENII errr functin uses exact ray data t cmpute aberratin-like perands in a highly efficient manner (it nly traces 11 rays and cnsists f 31 active perands). As we get ready t ptimize, it is a gd idea t check the perfrmance f the system in a way that we can cmpare it with the system perfrmance after the ptimizatin takes place. Fr this tutrial we will cmpare the Ray Intercept Curves (RIC) f this beginning design t the RIC analysis f the designs that we have when we finish. 17) Chse the "RIC Reprt Graphic" icn ( ) frm the graphic windw tlbar t perfrm the desired analysis. Once the analysis has been perfrmed, lck the graphic against accidental updating by right clicking anywhere in the graphic and chsing "Lck" frm the ppup list. 18) Chse "Optimize>>Generate Errr Functin>>GENII Ray Aberratin " frm the OSLO menu. 19) In the resulting dialg bx that pps up with the title "Geniierf", keep the default values and click n the "OK" buttn. After the dialg windw clses, it might appear that nthing has happened. Hwever behind the scenes, a set f perands has been created which cmprises a cmplete errr functin. We will nw view the set f perands t see hw the errr functin is cnstructed. 20) View the perand list yu just generated by chsing "Optimize>>Operands" frm the OSLO menu. An "Operands Data Editr" windw is pened which displays a list f ptimizatin perands that were just created. These perands make up the errr functin. The functin f each clumn in the Operand Data Editr is identified in the accmpanying figure. The ptimizatin errr functin is simply the cmpsite f this perand list. Sme f the acrnyms used in the "Name" clumn are cmmn abbreviatins fr ptical terms and aberratins. The definitin f all these abbreviatins are described in the OSLO n-line help under

8 Page 8 f 18 Optimizatin Tutrial Using OSLO Standard r Premium "Cntents>>Optimizatin>>Errr Functins>>Generate Errr Functins>>GENII Errr Functin." In this tutrial we will nly discuss a few f the abbreviatins we will need t use. Numerical list shwing each Operand number. Yu can add lines t this list just like any ther spreadsheet in OSLO This is the relative Weight f each perand when calculating the ttal errr functin. A weight f zer will nt cntribute t the ptimizatin calculatin. The imprtant thing t remember is that the weights a relative and can be >1 if desired. This clumn cntains the mathematical Definitin that is targeted t zer during ptimizatin. In this example each perand Definitin is just ne f an array f variables (OCMx) that get calculated behind the scenes. Since the OCMx variables are nt all that descriptive, users rely n the NAME clumn t remember the functin f each perand. Additinal perands viewed by enlarging r scrlling windw Minimize r Cnstraint mde setting. T cnstrain an perand means t slve fr it explicitly and take it ut f the ptimizatin calculatin matrix. Cnstraint mde shuld be used sparingly. As an alternative, use a higher weight n an perand instead. As a user, yu can supply a Name here t remind yu f the functin f each perand. This clumn is simply reprted by OSLO, it is nt actually used by OSLO in any ther way. In this tutrial example, the names were generated by the "pabs_template" cmmand which is assciated with the "Aberratin Operands " menu item. The meaning f the names shwn are explained in the accmpanying text f this tutrial. Unlike ther errr functins in OSLO, the GENII errr functin des nt typically need t be adjusted manually. In cmbinatin with the values shwn in the previus ppup dialg, the perands in the errr functin perate as a cmplete set and d nt need manual adjustment by the user. One particularly interesting item t nte is that with the GENII errr functin, the EFL f the system des nt need t be added as an perand. The GENII errr

9 Page 9 f 18 Optimizatin Tutrial Using OSLO Standard r Premium functin effectively stres the current EFL f the ptical system and targets the system EFL t remain a cnstant thrughut the ptimizatin. 21) Nte that a few f the perands have a weight f zer. With a weight f zer, these perands d nt cntribute directly t the errr functin calculatin. These perands stre r calculate values that get used by ther perands. Nte perand #12 which has a definitin f "OPD(1,2)/O6". The "O6" refers t perand #6 which is actually used in the calculatin f perand #12. T find ut mre abut the OPD(1,2) prtin f the perand, definitin, read sideline #2 at the end f this tutrial. 22) When yu are dne bserving the perands, clse the Operands Data Editr by clicking n the Red "X" in the upper left crner f the spreadsheet. Yu d nt want t save any changes yu might have inadvertently made in the windw. 23) Nte that in the upper right crner f the Surface Data Spreadsheet (the Operands Data Editr needs t be clsed t see the Surface Data Spreadsheet), the EFL is currently 10mm. This system EFL will be maintained at 10mm thrughut the ptimizatin by the GENII errr functin. 24) Befre prceeding with the ptimizatin, evaluate the current errr functin by clicking n the OPE buttn ( ) in the Text Windw tlbar. Again, if yu are having truble finding this buttn r yu want t learn mre abut this buttn, please refer t Sideline #1 at the end f this tutrial. Nte that the resulting analysis in the text windw ensures that the errr functin is set up prperly and that nly Since yu nw have variables and the errr functin has been created, yu are ready t start the actual ptimizatin. Hwever, just in case smething ges wrng, it is always wise t save yur lens just befre any ptimizatin. 25) Save the lens as "Triplet10mm_OptGeniiStd.len" in yur private directry.

10 Page 10 f 18 Optimizatin Tutrial Using OSLO Standard r Premium 26) Start ptimizatin by clicking n the ITE buttn ( ) frm the text windw tlbar. The ptimizatin will then prceed with a maximum f 10 iteratin cycles with each buttn click. Nte that the ptimizatin advances thrugh all 10 cycles. If yu click n the "Ite" buttn again, the ptimizatin des an additinal 3 cycles befre stpping. This is because the imprvement in the errr functin was less than 0.01% after iteratin #3. Lk at sideline #3 fr mre infrmatin abut changing the default setting f this ptimizatin parameter. We can nw evaluate the ptimized lens system in the same way that we did prir t ptimizatin. 27) Open up a new graphics windw by chsing "Windw>>Graphics>>New" frm the OSLO menu and then click n the "RIC Reprt Graphic" icn ( ) frm the new graphic windw's tlbar.

11 Page 11 f 18 Optimizatin Tutrial Using OSLO Standard r Premium 28) Lck this windw in the same way as befre by right clicking in the windw and chsing "Lck" frm the pp up list. Yu can nw cmpare system perfrmance with the baseline RIC Reprt graphic generated in step #17. 29) If the perfrmance f yur system matches what is shwn here, chse "File>>Save" frm the OSLO menu t save this lens in the "Triplet10mm_OptGeniiStd.len" file. If yu encuntered sme truble alng the way, cnsider retrieving the lens frm Step #16 r #25 and re-perfrm the intervening steps. Optimizatin using the OSLO Spt Size/Wavefrnt Errr Functin: The OSLO Spt Size/Wavefrnt (SS/WVF) errr functin creates the necessary ray perands t cmpute the RMS spt size (transverse ray errr) r RMS OPD (wavefrnt errr), averaged ver the field and, ptinally, cntrl clr. In the prcess f generating the errr functin, the necessary field pint set and ray set are generated s that the rays prperly sample the system. Althugh all generated errr functins allw the user t mdify and add perands, the OSLO SS/WVF errr functin is ideally suited fr the user t add ptinal perands such as perands that penalize insufficient edge thicknesses, r excessive distrtin. As yu start t wrk with this different errr functin, yu need t retrieve the lens yu stred befre the last ptimizatin started. 30) Chse "File>>Open" frm the OSLO menu and pen the "Triplet10mm_Start.len" lens stred in yur private directry. 31) Chse "Optimize>>Generate Errr Functin>>OSLO Spt Size / Wavefrnt " frm the OSLO menu. The resulting "Generate Errr Functin" dialg bx that pps up allws yu t chse hw yu want rays t be sampled acrss the field and the aperture, whether yu want t cntrl Spt Size r Wavefrnt Errr, as well as hw yu wuld like t cntrl clr, distrtin and edge thicknesses. 32) Chse the "Clr Crrectin Methd" t be "Use CHR/DMD perands" 33) Chse the "Crrect Distrtin Full Field" t be "On" and set t 0.5%. 34) Click the "OK" buttn at the bttm f the "Generate Errr Functin" dialg t accept the remaining default values in the windw withut making any ther changes. After the "Generate Errr Functin" dialg windw clses, it might appear that nthing has happened. But nce again, behind the scenes a set f perands has been created which cmprises a cmplete errr functin. 35) View the perand list that was just generated by chsing "Optimize>>Operands" frm the OSLO menu. Additinal perands viewed by enlarging r scrlling windw

12 Page 12 f 18 Optimizatin Tutrial Using OSLO Standard r Premium These ray perands cntrl particular rays which are sampled accrding t the field and aperture sampling that yu set up in the "Generate Errr Functin" dialg windw. If yu scrll dwn in the windw, yu will see that there are 109 perands in this errr functin, and they are all based n rays (fr a better explanatin f what the definitins such as "X(2,7)" mean, read sideline #2 at the end f this tutrial). There is, hwever, ne prblem with this current set f perands. If yu trace all these rays t try and minimize spt sizes n the image plane, and yu are als allwing all glass surfaces t vary curvature, there is n cntrl ver fcal length as this errr functin is currently written. 36) Insert a line in the "Operands Data Editr" spreadsheet by right clicking anywhere n the line f the 1 st perand and chse "Insert befre" frm the pp up list. Nte that yu can add lines fr new perands anywhere in the Operands Data Editr list, except between the "AVE" and "RMS" perands "AVE" perands. Out f cnvenience, it is best t add custm perands either t the beginning r t the end f an errr functin list. 37) In this new first line, enter a weight f 1, a name f "EFL" and a definitin f "EFL-10". Since definitins are always targeted t zer in OSLO, this definitin is nw targeted s that the EFL f the system will be maintained at 10mm thrughut the ptimizatin. 38) Clse the Operands Data Editr windw by clicking n the green check in the upper left crner f the spreadsheet. 39) Befre prceeding with the ptimizatin, evaluate the current errr functin by clicking n the OPE buttn ( ) in the Text Windw tlbar. The resulting analysis in the text windw ensures that the errr functin is set up prperly. Nte that the rays in the errr functin have been evaluated in 5 grups. Each f these grups cntain tangential and sagittal ray intercepts (the psitin where the rays intersect the image plane) that are RMSed tgether. Additinally there are grups f perands that cntrl clr crrectin and distrtin. The first line f the "Ope" analysis demnstrates that the EFL has been successfully added t the perand list. Since we nw have variables and the errr functin set, we are ready t start actual ptimizatin. Hwever, just in case smething ges wrng, save yur lens in its current state.

13 Page 13 f 18 Optimizatin Tutrial Using OSLO Standard r Premium 40) Save the lens as "Triplet10mm_OptOSLO_SS.len" in yur private directry. 41) Start the ptimizatin by clicking n the "Ite" buttn frm the text windw tlbar. The ptimizatin will then prceed with a maximum f 10 iteratin cycles with each buttn click. 42) Nte that the ptimizatin stps after 7 cycles. This is because the imprvement f the errr functin was less than 0.01% after iteratin #7. Lk at sideline #3 fr mre infrmatin abut changing the default setting f this ptimizatin parameter. We can nw evaluate the ptimized lens system in the same way that we did prir t ptimizatin. 43) Open up a new graphics windw by chsing "Windw>>Graphics>>New" frm the OSLO menu and then clicking n the "RIC Reprt Graphic" icn ( ) frm the graphic windw's tlbar. 44) Lck this windw in the same way as befre by right clicking in the windw and chsing "Lck" frm the pp up list.

14 Page 14 f 18 Optimizatin Tutrial Using OSLO Standard r Premium Nw yu shuld have three Ray Intercept Curves Analysis windws pen: One windw befre ptimizatin (step#17), ne after using the GENII errr functin (step #27) and ne using the OSLO Spt Size / Wavefrnt errr functin fr ptimizatin (step #43). Of curse bth f the different ptimizatins imprved the system (nte the 2.5x smaller scale n the Ray Intercept Curves after ptimizatin). But in this particular example it is nt quite clear which ptimizatin prcedure prduced a better system. The Ray Intercept Curves fr the GENII errr functin ptimizatin actually appear t be slightly better than the curves fr the OSLO Spt Size / Wavefrnt errr functin. What design criteria are mst imprtant (ray intercept curves, certain aberratins, r smething else) is usually dictated by the custmer r the applicatin, but fr sme situatins, we might be able t assume that the GENII ptimizatin prvided a better system. The n-axis Ray Intercept Curve (lwer left crner) f the GENII ptimizatin analysis windw appears t have slightly smaller errrs acrss the aperture that the alternative ptimizatin analysis. As an exercise, yu may want t g back t the ptimizatin using the OSLO Spt Size / Wavefrnt perands and see if there are ther perands that culd be added r altered in rder t make their perfrmance rival that f the GENII errr functin ptimizatin. 45) If the perfrmance f yur system matches what is shwn here, chse "File>>Save" frm the OSLO menu t save this lens in the "Triplet10mm_OptOSLO_SS.len" file f yur private directry. If yu encuntered sme truble alng the way, cnsider retrieving the lens frm Step #30 r #40 and re-perfrm the intervening steps. The purpse f this tutrial was t teach sme f the mechanics assciated with perfrming ptimizatin in OSLO. What yu have cvered here is just a small prtin f the ptical design prcess. An example matrix f this prcess is shwn belw. Starting System Design Add Variables Generate Errr Functin Add/Change Variables Save Design Edit Errr Functin OR Retrieve Saved Design Optimize Evaluate Errr Functin Perfrm Additinal Evaluatin OR NO Is Design Adequate? NO Cntinue with Tlerancing T becme an expert ptical designer, yu will need t gain enugh experience t handle all the decisin pints f the ptical design matrix. This hwever, is way beynd the scpe f this tutrial. YES

15 Page 15 f 18 Optimizatin Tutrial Using OSLO Standard r Premium SIDELINE #1 Nte that there is a series f three letter acrnyms (Len, Spe, Rin, etc.) underneath the title bar f the text windw "TW 1": These acrnyms are actually icns assciated with the current set f active tlbars fr the windw. Yu can change the tlbars that are shwn by clicking n the leftmst icn (a red framed blue windw) t expse a checked list f tlbars in the ppup list. Nte that in the figure belw, the "Standard Tls" item is checked which means that the "Standard Tls" is the nly tlbar nw shwing in the text windw. The Standard Tls tlbar cnsists f 17 text icns ranging frm "Len" t "Ite". If an icn is greyed ut, that means it is unavailable at the time. In the example shwn belw, the "Ope" icn is unavailable because n perands have been defined yet. Likewise, "Ite" is nly available after at least ne Variable and ne Operand have been defined. Text Windw Tlbar SIDELINE #2 OSLO Standard and Premium use a different methd t implement an errr functin than that in OSLO Light. In OSLO Light, users can nly implement perands that have been pre-defined in a CCL r SCP cmmand (these are called "user defined" perand cmpnents). In OSLO Standard and Premium, users can directly add and delete perands based n ray, aberratin and system parameters (these are called "built-in" perand cmpnents). The apprach used in OSLO Standard and Premium allws the user t easily add and mdify individual perands that in turn affect the peratin f the errr functin as a whle. The user defined apprach in OSLO Light des nt have this cnvenience f directly entering r mdifying individual perands in the "Operands Data Editr", but it des have extreme flexibility in creating custmized user defined perands. Of curse OSLO Standard and Premium have the capability f implementing "user defined" as well as "built-in" perands. Yu shuld read the dcument: Optimizatin Tutrial Using OSLO Light. Sideline #2 is f special significance since it addresses creating custmized perands using the OSLO Light methd f user defined perands.

16 Page 16 f 18 Optimizatin Tutrial Using OSLO Standard r Premium If yu are interrupting the fllwing f this tutrial t read this sideline, yu may want t save yur wrk befre cntinuing. Sme f the steps yu perfrm belw may affect the state f yur current lens system. 1) T learn mre abut using the type f perands available in OSLO Standard and Premium, we first make sure that an errr functin has been created. Fr purpses f discussin, implement the "OSLO Spt Size / Wavefrnt" errr functin by chsing "Optimize>>Generate Errr Functin>>OSLO Spt Size / Wavefrnt". 2) Click the "OK" in the resulting dialg bx t accept all the default values. 3) Chse "Optimize>>Operands " frm the OSLO menu t pen the perand set yu just created. 4) When the Operands Data Editr pens, nte that all the definitins refer t cmmand like "X(2,7)" and "Y(3,10)" 5) T investigate what this nmenclature means, g t the n-line help (hit the F1 key at anytime in OSLO). And g t the help page: "Cntents>>Optimizatin>>Errr Functins>>Operands". On the right side f the help windw is a page devted t an "Errr Functin Overview" and it describes the Built-in Operand Cmpnents" (these perands are nt available in OSLO Light). 6) The ray perands that we just saw in the perand list are general ray perands, s click n the "General Ray" hyperlink.

17 Page 17 f 18 Optimizatin Tutrial Using OSLO Standard r Premium This brings yu t the "General Ray Operands" page that describes sme f the varius perand cmpnents available t any OSLO Standard r Premium errr functin. Nte that the syntax fr the X( ) perand cmpnent is X( fpt, ray, wvn, srf, cfg). Parameters 3, 4 & 5, are pretty self-explanatry. But what are "fpt" and "ray"? Fr the "fpt" parameter, yu need t enter the number f the field pint in the currently defined field pint set. The currently defined field pint set is described in the OSLO menu under "Optimize>>Errr Functin Tables>>Field Pint Set." Likewise, fr the "ray" parameter, yu need t enter the number f the ray in the currently defined ray set (a ray set is the cmpsite f ray psitins as the rays pass thugh the pupil plane). If yu want t use the default value fr a parameter, yu d nt have t explicitly enter that parameter when yu call a cmmand, as lng as yu d nt wish t verride the defaults f any parameter t the right f it in the perand cmpnent parameter list. Nte that the EFL perand cmpnent that yu used in the secnd example in the bdy f the tutrial can be fund in the "System" perand cmpnent list shwn in a hyperlink n the "Built-in Operand Cmpnents" help page. There is much mre infrmatin n the tpic f perands in the Optics Reference and in the OSLO n-line help (assciated with the pages shwn here). The discussin in this tutrial shuld give yu a gd starting pint fr learning mre abut ptimizatin perands in OSLO. SIDELINE #3 T adjust parameters that cntrl the ptimizatin prcess, chse "Optimize>>Optimizatin Cnditins" frm the OSLO menu. The resulting dialg bx allws yu t change a number f ptimizatin parameters. The default value fr "Percent imprvement fr cntinuing full iteratins" is 0.01%. This means that nce an errr functin is reduced by less than 0.01% in a cycle, the ptimizatin prcess stps befre executing anther cycle.

18 Page 18 f 18 Optimizatin Tutrial Using OSLO Standard r Premium Last Md: 24 SEP 2002