Re: [Goptical] entrance pupil determination

[Aaron Webster]

Hi Tim,
If I remember correctly, there's a set_entrance_pupil() function which allows you to define which surface is used for the entrance pupil calculation.  Otherwise it uses the first surface.  I don't have it front of me now, but its probably part of system.

--
Aaron Webster

On Jun 17, 2013 5:05 PM, "Tim Saucer" <address@hidden> wrote:

Hi,

First I want to commend you on this project. I was working on something similar when I came across goptical and I'm very impressed with its layout and development.

I have a question in which I hope I'm not overlooking something very basic. Basically I'm not sure the best way to establish the entrance pupil for a lens system. Working through the Tessar lens tutorial, I'm confused about the establishment of the chief and marginal rays. From my understanding the chief ray should intersect the optical axis at the aperture stop. However looking through the code it seems that the system is assuming the first surface is the aperture stop. From the diagram it appears that way. Looking through the code, we never call set_entrance_pupil, so the first surface is assumed. Is this correct?

I was wondering if anyone had a method to define the entrance pupil or if I've overlooked something.

Thanks for your input!
Tim

Tim Saucer
Physics 236/241/261 Lead GSI
Sih Research Group PhD Candidate
Office: 4409 Randall, Lab: 1277 Randall
Department of Physics, University of Michigan