Patent ID: 6487014
Filing Date: 2002-11-26
Classification: G02B,G02F,H04N,Y10S

Abstract:
In an optical device for controlling a flow of light between ports and comprising a pair of polarizing devices, the improvement wherein said polarizing devices each comprise a stack of alternate high and low refractive index thin film layers sandwiched between two high refractive index substrates and employ frustrated total internal reflection and interference, the thicknesses of the thin film layers being such that an equivalent optical admittance of the film layers for s-polarized light is substantially the same as an optical admittance of the substrates for s-polarized light for a range of angles of incidence and a band of wavelengths when incident light is incident upon the low refractive index layers at an angle greater then the critical angle whereby substantially all the s-polarized light is transmitted, and the thin film layers having an equivalent optical admittance for p-polarized light that is substantially different from the optical admittance of the substrates for p-polarized light for a range of angles of incidence and a band of wavelengths, whereby substantially all the p-polarized light is reflected.