HiCan you please help me to set the “Field Height” in image simulation feature.I wish to use the image simuation feature in Wide angle sysyem, lets take for example “Wide angle lens 210 degree field.zmx” file in Zemax examples subdirectory \Sequential\Objectives. For a source file I took the file “Demo Picture 640X480.bmp”What should be the Field Height in this case? The digonal field 105 degrees? or the full Horizonatl field in degress? I wish that Horizontal field to much the Height of my detectorWhen I turned on the feature, the deafult Field Height parameter is 148 degress ? Why?I found this link:https://optics.ansys.com/hc/en-us/articles/43071095752467-How-to-set-up-Image-Simulation-toolbut still, I dont understand what Field Height parameter should I use.Thanks,Talimu

Hi all,I think I found a bug in the RMS wavefront error plotting tool - initially saw it in the 2025 R4 version, but I downloaded the latest 2026 R1 and it’s still there.I was working through some analysis and noticed a discrepancy in the RMS wavefront error values reported on the plot vs evaluation in the merit function. As seen in the example below, the merit function operand RWCE was reporting a fairly different value compared to the plot. Initially I assumed this was due to sampling, but the difference persisted (I also tried comparing rectangular array vs Gaussian quadrature). Next, on a whim, I evaluated the RWCH (chief ray reference) operand and noticed it did match the plot value, which I found odd, because the default for the plot is to reference the centroid. Looking closer at the plot, I noticed that although Centroid is selected as the reference in the settings, the title block reports “Reference: Chief Ray”. Likewise, when Chief Ray is selected in the settings, the plot sh

Hello all, I have a model of the objective, from the supplier as well the lens and wavefront data with Zernike values.The Zernike coefficients in the model do not match the values in the measurements which I assume comes from the manufacturing and assembly tolerances.I want to use the optimization function with the lens dimensions as variables, including tilt and decenter and use the optimization process to reach the dimensions and other parameters that yields similar Zernike values as the measurements.I set up the Zernike polynomial operands with the wavelength and other settings. Use the values of the different Zernike coefficients that I want to reach as “targets” in the editor but when running the optimization, I am far off from the values where I want to be. Am I making a mistake in setting up the operands? Or am I underestimating the complexity of what I want to do, and it will not be feasible?Measured valuesMerit function editor setup​​​​Has anyone performed such an analysis bef

I need the L,M,N values for vectors normal to plane surfaces in non-sequential mode.  I have tried many different ways, and just haven’t found the magic decoder ring yet.  How can I get surface normal components for plane faces on objects in non-sequential mode?

Dear all, In case it can be useful to others, perhaps ​@Robert.Campbell who previously asked:I made a paraxial interactive Kohler illumination simulation.The actual simulation can be launched here: https://kohler-simulation.microscopybench.com/.I have a description of it and a link to the Github repository where the OpticStudio files are hosted here: https://microscopybench.com/an-interactive-ray-tracing-simulation-of-kohler-illumination/.Currently there are some limitations and I cannot realistically add any other controls with my current workflow. If you have any idea how this could be improved, I’d appreciate your help. Perhaps ​@Erin.Elliott has some ideas?I’ll also post a similar content to image.sc: https://forum.image.sc/t/interactive-paraxial-kohler-illumination-simulation/119906.Thanks a lot and take care, David

I don’t know about other users, but I find the new help system that requires an internet connection with login to an Ansys account to be rather annoying and less user friendly than the previous built-in CHM help file.A while back, Tom posted a note that an option for accessing help files without needing an internet connection was in the works:Just wondering if someone from Ansys can comment?Thanks,Jeff

Hello, I am trying to simulate a LED array arranged in a circle with a collimation towards the center of the ring. For some reason, the source rays are interacting with a mirror I arranged in the same way but not with both collimation optics. Why are the lenses not considered in the simulation?Best, Thomas.

An error message is popping up which states: An entry with the same key already exists. I am curious why this error is occurring and what I can do to mitigate.Specifically, this error occurs when I perform a tolerance analysis with a single tolerance operand. I am using the TEZI operands to tolerance the surface form of a conical mirror, and if I only include zernike polynomial 5 (by setting Max# = 5 and Min# = 5). Furthermore, the error only occurs if the tolerance analysis criterion is set to Merit Function and when the RSRE operand is used in the Merit Function. Lastly, I did try to recreate this error on a simplified zemax model made from scratch, and was not able to recreate, which is quite unfortunate. It therefore seems somewhat tied to the specifics on my model. Regardless, I am hoping that understanding where this error comes from may give a hint as to what is happening. Adam  

Maybe it’s just me, but I am no more able of opening the “Go To Surface” popup window from any Editor.The following does not come up (image taken from Help file):I am using opticStudio version 2025 R1.00

I came across the Seidel Coefficient page and found a typo. 

I'd like to point out some mandatory features which, in my humble opinion, the ISO Element drawing utility lacks. I'm probably referring to all well known issues, but still, I believe them to be of paramount relevance to be left unsolved over the years. 1) support for triplets. 2) xml file support for doublets/triplets. More on this, I report a sneaky behaviour of the current feature: if a doublet design is saved, no error is reported by OpticStudio and an empty xml file is saved instead, so that the average user can believe its manually inserted data are securely saved, but actually they are not. When opened, such xml file just reports the string 'XML output is not currently supported for doublets'. 3) drawings saving in a native vector format, such as pdf or svg. At the present time an external pdf printer sw is needed to do so, often with unpredictable results. The same request holds for every graphic output of OpticStudio (diagrams, histograms, plots,...). The cha

Good morning, good afternoon,I am trying to set boundaries on longitudinal compensators on my tolerancing analysis with Monte Carlo runs. As I am using a Merit Function criterion, the boundaries (from what I understood), must be explicitely defined in the Merit Function tab with the PMLT and PMGT operands for each surface that acts as a compensator. I did set them, as you can see in the next screenshot.I also declared the compensators in the Tolerance Data Editor (2nd screenshot), by using the CPAR operand (I found a topic on the forums explaining that it was the method to follow). I declared the 4 compensators I wanna use (I would like to use the thickness of these surfaces as compensators), so I did use the #1 parameter. But when I try to run the tolerancing, the error message appears (CPAR 6 1 is invalid). Would you know where this problem comes from? Maybe I am not doing this the right way or there is another method to do so.Help would be greatly appreciated!Thank you very much :DM

Hi, I am using Physical Optics Propagation and try to compute the coupling into a monomode fiber.Should I use “Gaussian Waist” as fiber type? I think “Top Hat” is for multimode, right?And what is “Waist X-Y”, is it the physical diameter onf the fiber core, or the Mode Field Diameter (MFD) of the fiber?ThanksJulien D. 

What is the difference between Orthogonal Descent and Damped Least Squares?

Hi, I am trying to use RMS wavefront as criterion for tolerancing. When I check the value of the criterion in the tolerancing tool, it is 10 times lower than in the wavefront map! I tried to improve the sampling either in the tolerancing menu or in the wavefront map menu, but it didn’t help. I only have one wavelength and one field to simplify.Thanks if anyone has an explanation…Julien

Dear all,I have a question regarding the Quantum Yield when used in the Phosphors and Fluorescence Volume Physics section in the non-sequential mode.I have a simple setup in Zemax (file in attachment) where I want to replicate a fluorescence quantum yield measurement. It consists of a collimated monochromatic excitation source, a rectangular volume with the volume physics set, and a polar detector capturing all the scattered and fluorescent light. The absorption spectrum is flat at the excitation wavelength (550 nm), the emission spectrum is an arbitrary curve around 600-700 nm, and the quantum yield spectrum is a single value of 1. I have chosen the extinction coefficient such that around 60% of the light is absorbed/re-emitted and the rest is transmitted normally.With this setup, I would have expected that no light would be lost. However, looking at the total power captured by the polar detector, only 93% of the light remains. Looking at the flux vs wavelength plots shows that we hav

Dear members,I am trying to use the NSC quick Focus button but an error occurs saying that there are not Sequence /groups available.What is a sequence or group and how can I define it? Thanks Regards Gabriele

Hello,I need to model an imperfect retroreflector, such as those found on safety jackets or road signs, as shown in the picture below. I would like the retroreflection to be within a cone of angles ranging from 2 to 10 degrees from the source.In Sequential mode, I discovered that we can add a retroreflector surface, but the beam still only reflects from the original source. I tried changing the scattering surface, but even when I used a Lambertian, Gaussian, ABg or BSDF and set the Scatter Fraction to 1, it still didn’t work. The rays still go back to where they came from.In Non-Sequential mode, I managed to add a Lambertian, Gaussian or BSDF in the Scatter Model panel, but when I give an angle to the surface, there is still a specular (BRDF) effect. There is something to change here but I don’t know what nor how.Is there a way to simulate such backscattering or retroreflection?Thank you for you help

Hi friends,I don’t have part designer, so I always struggle to get a CAD file to a User defined surface. Looking at all the posts closest I see is the link below, but the author never posted the .csv file or the CAD so I can’t test the code since step1 and step2 didn’t work out for me. Wondering if anyone else had the same issues and if someone figured out a way to convert a CAD file to a closed loop freeform or a aspheric surface?Converting CAD data of the TIR lens into the parametric surface for optimization in NSQ mode | Zemax Community 

I know I can manually load the ZTD file using Tolerancing data viewer and copy the data to excel.  I would like to automate the procedure using Matlab or Python since I have more than 50 ZTD files. Thank you very much.

ZBF stands for Zemax Beam File. This format is used in POP to describe the beam at a surface.To create a ZBF text file manually, here are two useful documents:- an Excel sheet that summarizes the syntax of the Help File (The Analyze Tab (sequential ui mode) > Laser and Fibers Group > About Physical Optics Propagation > Defining the Initial Beam > File (defining the initial beam) > Zemax Beam File (ZBF) text format > Zemax Beam File (ZBF) text format). The G column of the tab "ZBF" of the Excel sheet is a ZBF file. To create a ZBF file, copy that column into a text file and save it with a ZBF extension under \Zemax\POP\BEAMFILES. The two other tabs represent and plot the data as a matrix.- the ZBF text file created from the Excel sheet History:Date Version OpticStudio Version Comment 2019/05/20 - - Creation 2020/09/04 v2 - Updated the Excel file with non-zero imaginary profile.  2021/01/06 v3 - In the Pivot_Table tab, there are now 3 colum

HiI am using 2025 R2.02 version. It looks like the issue previously reported about the ISO drawing has been partially solved which is cool (https://community.zemax.com/topic/show?tid=5444&fid=7).I still have one problem, it’s the number of digits used for the SAG and edge thickness on the drawings.There is 5 to 6 digits on my drawing. In the L (R) surf TAB of the drawing, you can uncheck the Automatic box and change the surface sag but it seems to have no effect on the drawing… Do I miss something?Renaud

 Hi Zemaxers,I am trying to understand a non‑paraxial optical system.The system is a decentered lens, and I would like to determine its focal length and the chromatic focal shift.My current understanding is that, since the system is non‑paraxial, even the “paraxial rays” need to go through the coordinate breaks. I tried this approach and obtained the results shown below. However, I am having difficulty interpreting them.In particular, I am unsure how to evaluate the chromatic focal length shift in a non‑paraxial system.As the software states: “This plot may not be meaningful for non‑paraxial systems.”So I’m not sure what the correct method is.Can you kindly give me some advice on these issues?    btw here,  Analysis...PAL/Freeform...Pupil Map  suggested by @Mark.Nicholsonhttps://community.zemax.com/got-a-question-7/non-paraxial-focal-length-3672 I am not sure is it similar to my issues? best regards Yang

Hi All, I have a question regarding EXPP. It seems from the comments here that Zemax calculates EXPP by tracing two parabasal rays +y and -y which are 1e-3 deviated from the on-axis ray (not sure if deviation is in normalized field coordinates, ray direction at stop, or something else) and then find their intersection. I have a few questions regarding that: Is EXPP (which is just a Z-offset from image plane) the plane used to draw the reference sphere for OPD and PSF calculations? Why do we not also trace +x and -x rays and how this affects the accuracy of the reference sphere? That value of EXPP seems to differ if Ray aiming is OFF vs Real. How does the calculation differ in each case? Since EXPP uses parabasal rays, it should be accurate for decentered and tilted systems? Thanks a lot for your insight. Best, 

Hello,After following the next article: The easiest way to tolerance an off-axis mirror I have been struggling to manage the tolerances in my system since it has 2 different OAPs and as in the example, I have set one of them as the global coordinate reference Apart from that issue, I really don't think my coordinate breaks are working properly to tolerance the OAPs (I only want to check the decentered and tilt tolerances).Lastly, I don't really know why final focus is not hitting the center of the image.Thanks