Abstract

The reststrahlen reflectance of crystalline materials can be enhanced with coatings of nonabsorbing interference films. At the same time the reflectance curve is altered to be nearly rectangular in shape as is more appropriate for infrared reflection filtering. The coatings consist of single films or are designed around symmetrical three- and five-film periods. PbCl₂, ZnTe, and Ge were used for coatings on MgO, LiF, CaF₂, and ZnO substrates as examples of reflection filters in the 14–36 μ infrared region.

© 1965 Optical Society of America

Reflection Measurements on Reststrahlen Crystals in the Far-Infrared Region

Akiyoshi Mitsuishi, Yahiko Yamada, and Hiroshi Yoshinaga
J. Opt. Soc. Am. 52(1) 14-16 (1962)

Optical constants in the IR from thin film interference and reflectance: the reststrahlen region of muscovite mica

Edgar B. Singleton and Charles T. Shirkey
Appl. Opt. 22(1) 185-189 (1983)

Infrared Reflectance and Emittance of Silver and Gold Evaporated in Ultrahigh Vacuum

Jean M. Bennett and E. J. Ashley
Appl. Opt. 4(2) 221-224 (1965)

Infrared Filters of Evaporated Gallium Arsenide

R. P. Howson
J. Opt. Soc. Am. 55(3) 271-275 (1965)

Bandpass Filters for the Ultraviolet

P. W. Baumeister, V. R. Costich, and S. C. Pieper
Appl. Opt. 4(8) 911-914 (1965)