Abstract

One approach to the thin-film synthesis problem is to search for the best index profile, be it continuous gradient index or discrete multilayer, for a given optical thickness and index range. This formulation is sufficiently general to include a global optimum solution and is also practical now that gradient-index deposition methods have been demonstrated. One approach for finding such solutions is a method (first introduced by Snedaker in the 1982 OSA Annual Meeting) that divides the total thickness into many incremental layers and successively finds the optimum index within limits for each sublayer. We have successfully used this approach and have expanded on it in various ways to obtain nearly equivalent configurations that are more favorable for fabrication. It turns out that for many problems the solution is discrete multilayers at the low and high index limits. Solutions to difficult problems often yield new insights for standard approaches.

© 1992 Optical Society of America