Wire Grid Infrared Polarizer

Abstract

A useful polarizer for the 6-μ to 20-μ region has been designed, fabricated, and tested. A microscopic wire grid was formed by ruling Irtran 2 (ZnS) or Irtran 4 (ZnSe) and evaporating aluminum preferentially on the groove tips. The average transmittance for the crossed polarizers in the 8-μ to 20-μ region was less than 1%. The degree of polarization was insensitive to a wide range of incidence angles. Data showing the spectral polarization efficiency as a function of wavelength are presented.