Abstract

The present day important commercialization of optical thin film coatings grew out of work carried out in the 1940's and 1950's, largely in a few industrial laboratories. During this period the vacuum evaporation method for depositing thin films, both metals and non-metals, emerged as the most versatile. Coatings plants were developed to carry out this technique, methods were devised for in situ optical monitoring of film thickness during deposition, and a multitude of evaporant materials was uncovered, mainly by trial and error. A whole new world of applications beyond simple anti reflection coatings was discovered and coating structures became complicated multilayers. Quarterwave stacks came to be routine as dichroic beam splitters or as components of wide and narrow band spectral filters. Calculations progressed from simple vector representations through admittance chart manipulations to sophisticated computer programs for extracting reflectance, transmittance and phase data from theoretical multilayer designs. Thin film optics became established as a discipline in its own right and important theorems were evolved to aid the film designer. The author was privileged to participate in this march of events. His talk will focus on some of the commercial coating projects, as well as laboratory trivia, which he encountered along the way.

© 1984 Optical Society of America