Patent ID: 6788461
Filing Date: 2004-09-07
Classification: G02B,H01Q

Abstract:
A method for designing a broad band wire grid polarizing beamsplitter, the wire grid polarizing beamsplitter comprising a dielectric substrate with composite wires each having a stratified intra-wire substructure of multiple metal layers and alternating dielectric layers; the method comprising:defining a desired range of incidence angles and a desired spectral band of the incident light; defining the desired polarization contrast ratios within said spectral band for both the reflected polarized light and the transmitted polarized light; defining the desired minimum acceptable light efficiencies for both said reflected polarized light and said transmitted polarized light; selecting initial design parameters for the wire grid pitch and the width of the individual composite wires; selecting initial design parameters for said stratified intra-wire substructure of multiple metal layers and of alternating dielectric layers, which includes the number of said metal layers, the number of said alternating dielectric layers, the periodicity or aperiodicity of the arrangement of the layers within the intra-wire substructure, and the thickness of the individual metal and dielectric layers; selecting the materials which comprise the dielectric substrate, the individual metal layers, and the individual dielectric layers; and varying the design parameters in a selective and iterative manner until the desired performance for both the reflected polarized light and the transmitted polarized light is obtained.