Problem with finding out conjugate plane

  • 13 June 2024
  • 2 replies

I have the Stop aperture (pupil plane). Now, I want to find the conjugate plane to it which is somewhere after the 4f system (second lens, after surface 12). Can you please help me with how to do that in Zemax Opticstudio? Thank you in advance. Look at the attached file.


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Next time, please consider sharing the design file with us and not just the lens data (I don’t think anybody is going to copy those values in their Lens Data Editor to test). I know you can’t attach a ZAR directly to a post in the forum, but you can ZIP the ZAR and upload the compressed file instead.

Assuming you have a single conjugated plane on each side of the aperture stop, those are typically called entrance and exit pupils. A paraxial calculation of the position of the entrance and exit pupil can be found in the Analyze..Reports..System Data. This is an example from the Double Gauss 28 degree field sample file:

In the more recent versions of OpticStudio, you have the posibility to plot the paraxial, and real entrance and exit pupils in a 3D Layout. More details here:

There might be a way to find such conjugated planes with the Merit function similar to how @Erin.Elliott did in her example linked above, but it might depend on your system and without a file, its hard to say how you should go about it.

I hope this helps and take care,



Hey, I am using the 2023 R2 version, and here Draw Real entrance/exit pupil, paraxial pupils options are not available. I am sharing the Zip file having the .zmx and .zda files; as .zar is not available here.  Again, my goal is to find out the conjugate surface where I will have the exact Zernike aberrations to the surface 5 ( which is Stop aperture here, commented as pupil ). Thanks a lot for your kind help.