Abstract

There is a need to compare the computation times of, and the results obtained by commonly used thin film design methods. Clearly it is desirable, for a given problem, to employ a method which yields good solutions in a reasonable time. In particular, the solution should be based on the use of only a few materials because such systems are easier to produce in practice. An intercomparison of ten different refinement methods has been published recently.¹ In this paper a similar study is performed for the following numerical thin film synthesis techniques: comprehensive search, gradual evolution, flip-flop, minus filter and inverse Fourier transform methods. For this purpose a common master program was written that provides for timing and for the input and output of data, and which can invoke each of the above methods in turn. Calculations were performed on several examples. The results are presented for each method in diagrams that show the spectral performance of the resulting multilayer, its refractive index profile, and the variation of the merit function with computation time.

© 1990 Optical Society of America