Hi,
Here are some links to useful resources:
1. Book: "Optics: Learning by Computing, with Examples Using Maple, MathCad, Matlab, Mathematica, and Maple" by Karl Dieter Moeller: http://communities.ptc.com/docs/DOC-1603
2. Mathcad worksheets (include "Optics of planar layered structure"): http://www.physic.ut.ee/~kiisk/mcadapps.htm
3. Mathcad E-book "LightPipes for Mathcad Optical Toolbox": http://edu.tnw.utwente.nl/inlopt/lpmcad/
http://edu.tnw.utwente.nl/inlopt/lpmcad/
http://edu.tnw.utwente.nl/inlopt/lpmcad/demoversion/index.htm
4. Mathcad worksheets on the old Mathsoft site (include "Optical Multilayer Analysis"; "Reflection and Transmission Angles in Dielectric Media"):
http://web.archive.org/web/20061016100639/http://www.mathcad.com/resources/mathcad_files/