By replacing the silver layers in the conventional interference filter with seven dielectric layers having alternately high and low indices, it has been possible to obtain a filter having an 80-percent peak transmission and 65A half-width for a first-order transmission band centered at 5200A. The properties of the filter are determined from the theory of the parallel-plate interferometer.
HARRY D. POLSTER, "A Symmetrical All-Dielectric Interference Filter," J. Opt. Soc. Am. 42, 21-23 (1952)