I'd like to post the following message to your discussion board. Thanks! I am looking for reliable and accurate data on the temperature dependence of the index of refraction of pure silicon at 1.5 microns wavelength. Anyone know where I can find this? ------------------------------------ Dr. Randy D. May Director of Product Development SpectraSensors, Inc. 2400 Lincoln Avenue Altadena, CA 91001 Tel: 626-296-6325 Fax: 626-296-6329 Email: rmay@spectrasensors.com ------------------------------------