Abstract

This paper proposes three methods to design reflection filter. The first method is to design a reflection filter being composed of ultrathin mettallic film of Cr, F-P filter of all-dielectric and a high reflectivity film of Ag. The general structure can be expressed as A/CrXL(HL)^N (LH)^N ZLAg/G where N is the number of periods and is an integer, X and Z are phase accommodation coefficients for maximum reflectivity at central wavelength λ₀, H is high refractive-index dielectric layer, its optical thickness is λ₀/4; L is a low refractive index dielectric layer, its optical thickness is λ₀/4, and the geometric thickness of Ag film is 100nm its design example is A/Cr0.93LH2LH0.76LAg/G, where n_H =2.35, n_L=1.35, n_g=1.52, n_A=1.52, N=1, d_Cr=7nm the spectral refectance Curve shows in Fig.1.

© 1998 Optical Society of America