Principle Plane Output from Zemax

A friend of mine asked if there was an easy way to output the principle planes of a system in Zemax? I am sure I have done it before, but I figured it would be best to ask the experts. Therefore, @Isaac or @hkang do you guys have a suggested method?

There is most certainly a way to export this data! Under the Analyze tab, within the Reports section (look close to the right hand side in the default ribbon) there is a tool to output the Cardinal Point Data.

For a more in depth report, the Prescription Data report contains a lot too!

1 Like

Also, in the Merit function editor, you can use CARD operand to get cardinal points.
Btw, those points were not accurate if the system is off-axis or using freeform.So the user should always double-check.

Ah thats good to know, thanks @hkang

That’s a really good point! When dealing with freeform system, our notion of Gaussian optics behavior starts to break down. However, as a more optical philosophy question, when does the Gaussian approximation really not apply?

Even a spherical surface doesn’t follow Gaussian behavior perfectly because of aberrations. For example, lets say I have a spherical surface and then I add 2 waves of astigmatism to the surface. Does this freeform surface no longer have well defined cardinal points? I would argue that it does, which begs the question, when does it not? 10 waves? 100?

I think the boundaries of when and how to apply the first order optical principles to a freeform system are not very clear, and the tools to evaluate our assumptions should be developed further. What techniques have you used @hkang to evaluate when you can use first order optics in a freeform system?

As mentioned above, the principal plane poss are given in the prescription output. Also, there is a Knowledge Base article showing how to display them on the layout plots.