Hello All,
I would like to know how to make/model lens in radiance. So, Does anybody
know about how to make Lens material in Radiance. Please if some one knows
about it then let me know as soon as possible.
Thanks
Bye
--
With Regards
Neha Singhal
CEPT University
Ahmedabad
Dear Neha,
Radiance uses ray-tracing to perform lighting calculations in buildings. It is not configured for optical ray-tracing. For such a purpose, you are better off with any of the number of commercial packages available (TracePro, Optics Lab, ORA LightTools, etc.) While it is *possible* to use Radiance for optical design, it is not geared for it, and you won't find many people who have applied it to this task. I am just starting to work with it myself, but even the accurate definition of a lens given the lack of bicubic patches is problematic.
Best,
-Greg
From: "NEHA SINGHAL" <neha.cosmos@gmail.com>
Date: December 26, 2008 2:08:59 AM PSTHello All,
I would like to know how to make/model lens in radiance. So, Does anybody know about how to make Lens material in Radiance. Please if some one knows about it then let me know as soon as possible.
Thanks
Bye--
With Regards
Neha Singhal
CEPT University
Ahmedabad
There are even some open source and free packages available for such systems, but I do not know anything about all this 
I have attached some info, but again, I do not really understand what I am posting here! Tell us if it is useful for you! Again, if you want to model some basic effects of what happens in lenses, you may try the pmap-extension for radiance or Carsten's rewrite "radzilla", which allow e.g. caustic effects. Besides that you should read everything concerning glass, dielectric, trans and interface modifiers in radiance several hundred times 
You can also have a look at renderpark, a tool that has not been developed for a while, but has some radiance compatibility (it understands the mgf format) and implements several forward-raytracing engines. This software has always been considered as experimental, so it may be great to experiment, not to sell...
CU Lars.
--
- Tessa (install using apt-get install tessa on debian or other, debian-based distributions):
From Tessa's README (available e.g. from recent Ubuntu's):
"This is Tessa 3D-FDTD. This software is designed to study optical
structures at the wavelength scale using the finite-differences
time-domain method. The Tessa home-page is located at:
http://alioth.debian.org/projects/tessa/
You can always find the latest version here.
This software is free software, and as such comes with ABSOLUTELY NO
WARRANTY, to the extent permitted by applicable law.
Tessa was developed by:
Josselin Mouette
Laboratoire d'électronique, optoélectronique et microsystèmes (UMR 5512)
École centrale de Lyon, France"
- Opus
From the website (http://www.maxreason.com/software/optics/opus.html):
opus is a software application for designing and evaluating optical systems. The first release of this opus software application was created by greatly cleaning and simplifying the application the author had enhanced and extended over decades on an as-needed basis. This was done purposely to create a reasonably clean, simple, straightforward code base suitable for enhancement and extension by other programmers. Some capabilities were removed in this process - to be re-implemented more cleanly and efficiently.opus computes AKA "traces" the path of light "rays" from an "entrance-aperture" or "object-plane", through a series of "optical surfaces" (lens-surfaces, mirror-surfaces, vignette-stops) to a focal surface, where opus computes image error "aberrations" at several "field-angles" and colors AKA "wavelengths".