🚀 go-pugleaf

I am looking for an optical modelling program (i.e. ray tracing
program or based on physical models) which will suitably model 
general relective and refractive surfaces (in particular beamsplitters) 
to use in modelling an interferometer. 

Most commercial packages of which I am aware do not model refractive 
surfaces / beamsplitters. It may be PC (DOS), VMS or unix based. I also 
would like to determine modulation transfer functions of the device for
a range of wavelengths if possible.

I am aware of the commercial package CODE5, but I'm looking for
something more affordable (public domain great) and portable.

*************************************************************             
*        Roy J. Hughes                                      *
*                                                           *               
*        Centre for Instrumental and Development Chemistry, *
*        School of Chemistry,                               *
*        Queensland University of Technology,               *
*        Brisbane, Queensland, Australia, 4000.             *
*                                                           *
*        Postal Address: GPO Box 2434, Brisbane, 4001.      *
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*        Phone: 0011-61-7-8642825(Work)                     *
*               0011-61-7-2077402(Home)                     *
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*        e-mail: r.hughes@qut.edu.au                        *
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