Hello there friends from the Zemax community,I would like to ask for your help with a situation that I have. I am trying to optimize for a lens which is supposed to couple light from a collimated beam into a single mode fiber.This is the procedure that I always try to use:I use the FICL operand in order to estimate the fiber in-coupling efficiency, i.e, the overlap between the incident field and the defined fiber mode. For the fiber mode I always use the NA of my fiber. Additionally I use a standard spot size operand in order to obtain a non-aberratated spot at the fiber plane. I optimize for the spot and adjust the length of my collimating beam “free space” region in order to match the size of the spot needed for coupling into the fiber. In general, the wider the input collimated beam, the longer my free space region needs to be in order to have the right spot size at the fiber plane. I use the FICL operator just as a monitor to have an estimate on the coupling efficiencyInstead of us

Since the latest Zemax update my files no longer work when I conduct a ray trace, all my files crash terminating Zemax.  I’ve rolled back to 23.1 and I can do a ray trace again without my files crashing (sometimes because I saved the file in 23.2 and it changed something in the file older versions of Zemax don’t like), but I have now run across another issue.When I do a ray trace I get “NA” for pixel values on both surface and rectangular detectors.  Does anyone have any experience seeing this?  Is it something I have changed that could cause this?  

Imagine the doublet as pictured below. (Surface numbers and thicknesses shown) fig.1. This would be the nominal system. If we want to manufacture this system, we will have to tolerance these thickness values. Let’s say the thickness on Surface 1 comes back from the manufacturer and is measured to be 6.5mm. We could put the system together in one of two ways.   First, we could just make the whole system longer by the 0.5mm like so. fig.2. Or, we could make the thickness on surface 3 shorter by 0.5mm and have the total length remain at 104mm. fig. 3. This choice is up to the design and the designer, but this is where the ‘Adjust’ parameter comes in. If we don’t want to adjust any thicknesses to make up for the change of thickness on Surface 1, we would just input the same surface value in the adjust column. This will correspond to the system in fig.2. If we want to adjust the thickness on Surface 3 to make up for the change, we would change the &lsqu

I have imported a collimator that I made in Solidworks  into Zemax and started a non-sequential raytrace, I would like to send rays throughs my four lenses but can’t to figure out how to do so.  

I could use a little radiometry help here.  Night sky luminance can be quantified in terms of visual magnitude/arcsecond².  Pristinely dark skies with no light pollution or airborne dust are in the range of 22.0 mag/arcsec² (~172 μcd/m²).  The Milky Way in a clear moonless sky has a luminance of around 19.6 mag/arcsec² (~1561 μcd/m²).  Light-polluted skies can have a luminance of 18 mag/arcsec² (~6814 µcd/m²) or worse. The formula to convert mag/arcsec² to µcd/m² is value in µcd/m² = (1.08E+11) × 10 ^ [-0.4*(value in mag/arcsec²) ]1 cd = 1/683 watt/ster at 555nm.  In non-sequential mode, how would one model a patch of the night sky based on its mag/arcsec²?  I’m assuming one would use a Source Ellipse of some diameter at a negative distance from an optical aperture to define the solid angle, and with the Cosine Exponent set to 1.0 to give a Lambertian luminance pattern.  Say I set the number of analysis rays to 1E7.  What formula gives me the power in watts for a given number of analys

Hello I have a question on the tilt x and y values, in the text tap of the Surface Sag map.When I create the OAP and try to extract the sag map, it shows certain values.What does mean of tilt? Was the data in text tilted by displayed angle? (To have the center of sag map to be normal to projection angle?) If this means tilt, the aperture should be oval shape with cosine factor.  

"You must be an end user of a supported license to read the full article." This will make my day job more difficult. Ugh - can't edit the title either; that was a whose; not a who's, Horton. M

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

I'm trying to figure out a way to pull the text data generated by the Polarization Pupil Map analysis tool in OpticStudio into python using the ZOS-API Interactive Extension so that I don't need to download text files. Does anyone know how to do this?  

Hi,Is it possible to find a patent of the exact objective model based on the part number available on the manufacturer’s website? If I find the patent of the objective with the same main parameters ( like NA or magnification) how do I know that this is the exact model I am using?Regards,Marzanna

How to model atmospheric turbulence using grid phase in Zemax? Which external software can be used for simulation of atmospheric turbulence?

Please consider adding an 'Ignore Lateral Color' option to the Rayfan and OPD plots. This would help in diagnosing spectrometer image quality and formulating next actions. Thanks, Mike

Hi,I would like to simulate a car headlamps (several types) with OpticsStudio. I need to use exists illumination models (and not write it by myself, because I don't have any access to the technical information of real headlights.How can I achieve these models?ThanksDan  

In non-sequential mode, is it possible to view only a portion of the segments of a ray?I’d like view only segments after hitting a particular surface.You can filter by hitting a surface, but it always displays the entire sequence of rays.The functionality I’m after is similar to specifying the ‘First Surface’ and ‘Last Surface’ in the sequential viewers. Thank you,John

Hi, I am using two radial sources and one polar detector. I would like to export the data on the polar detector as IES/LDT.I’ve done this successfully with a source volume, but with a radial source it does not work. It tells me an error message saying that there is no photometric data found on the detector. When I look at the detector it shows data.What am I doing wrong or not understanding?   Thanks

Hi all, I would like to test a variety of lenses in a 2-lens Keplarian beam reductor. What is the best way to optimize this design to get the BEST collimation with the pair of lenses? I have used the optimization wizard with a variable Z-axis distance. The criteria settings are attached. Occasionally, the optimization function does not change the Z distance of the second lens even after I put it in an incorrect Z-position. Can someone please advise? Thanks!  

Hi all,I try to use Zemax Element Drawing for my tolerance analysis report. However, I found the value of Radius tolerance after I clicked Reset from TDE are not consistent with values from Tolerance Data Editor.  The below picture shows that the tolerance for surface 1 is 0.0366 (note: my first surface is 2), however the TRAD for surface 2 is +/-0.1. Could someone explain what happened here? Thanks,Xiaolei

Hello everyone,I got an Excel-sheet with beam information, it is attached, which I would like to convert to a suitable .DAT file for the Object type “Source file” in the non-sequential mode. I understood it like this: in the first line you determine the number of rays and the unit, I use “mm” so I wrote a 4. From the second line, my beam-data starts. The columns 1, 2 and 3 determines the coordinates x, y and z, the columns 4, 5 and 6 the angle in the different room directions. The next columns give information about the value of the power, you can add another column for the wavelength, I only work with one, so I left it out and add the wavelength over the system explorer.My question belongs to the angle, I couldn’t figure out how I write it correctly, so the program can propagate the light. It appears an Error Message: Invalid direction cosines for ray 1 in source file. All angles are added the same way, so it appears for all rays.So how should convert the angle so Zemax can work with

Hi,I would like to simulate that light travels through a single mode fiber, and a coreless fiber, and the end of the coreless fiber is a tilted flat surface, so the light will be reflected because of total internal reflection or reflective coating. My problem is that I can not keep the aperture constant (usually the cladding of SMF and my coreless fiber is 125um) because of the titled surface, as shown below. Is there any method that is able to keep the diameter consistent  (125um) ?  Thank you! Oliver

Is there a way to sample an image in a similar way as a Bayer sensor for the Image Simulation tool? Without making a custom Bayer slide surface for each image and imaging system?For example: sampling an input image BMP as RGGB assuming bands 3+2+2+1, then providing the option of a raw or de-mosaiced color simulated image.  

HiI am working on calculating the coupling efficiency of a multimode fiber from a simple aspheric lens system using the optimization feature. I tried first with NSQ mode (below picture) but realised after seeing the article below that SQ is more appropriate in my case. https://support.zemax.com/hc/en-us/articles/1500005486601-How-to-model-multi-mode-fiber-couplingin SQ mode, I have issues placing the lenses within their focal distance from each other and get the following:This question must be really basics but any tips on how to move the lenses from each other? Eventually I want to try the setup with lenses of varying focal lengths so I should be able to move them. The articles online suggest changing the thickness but that just distorts my lens. Any help is appreciated.Thanks,Hasti 

hallo,i had been working with regular LED´s as my source of illumination and was planning to change the source to be collimated, i tried looking into the merit functions but nothing came up. Can someone help me with this. 

Hi,I have a problem while performing the lateral color analysis of my optical system.Everything seems to go right, the MTF calculates as expected and all of the rays trace to the image plane.While using the lateral color analysis, i get the following discontinuity:  Could you help me find the reason for that?

Hello everyone,I would like to model a multi channel optical system using the Multi Configuration editor.However, for each optical channel I have a different optical surface (‘dat file’) I would like import using Grid Sag option.Is there a way to import multiple optical grid sag surfaces using the Multi Configuration editor? Thank youI would like change the import data file between each channel (config) in the MC editor 

Need HelpI wanted to have surface 10 as a reflective surface (like a mirror). However, when I trace the ray, in 3D, the light ray doesnt seem to reflect. Any idea why?