Re: [Goptical] entrance pupil determination

[Tim Saucer]

Hi Arron,

Thanks for the quick reply. The problem I see with set_entrance_pupil is that 
it assumes you've chosen it correctly. It just assigns whatever surface you 
send to it as the entrance pupil, even if that's not correct for your system.

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

On Jun 17, 2013, at 11:18 AM, Aaron Webster wrote:

> 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
> 
>