Radiation filters for the terahertz range using total internal reflection phenomenon

Abstract

The optical filter under development employing frustrated total internal reflection is a micro-mechanical device containing two silicon rectangular prisms. There is a flat silicon plane among hypotenuse edges of the prisms. The silicon plane is a Fabry-Perot resonator, with clearances h1 among the plate and prism edges being its mirrors. Theoretical resolution of the optical filter would be R ≈ 1,5·10³ if h1= 50 µm and R ≈ 3·10⁵ if h1 = 100 µm with the thickness of the silicon plane being h = 65 µm; wavelength λ = 100 µm; free spectral region Δλ/λ ≈ 0,3…0,4, transmission in the maximum of spectral characteristics 0,6 (provided input and output silicon prism legs bloom).