Patent ID: 7548671
Filing Date: 2009-06-16
Classification: G02B,G02F

Abstract:
1. An optical device, comprising: a horizontal waveguide grating structure (WGS) comprising at least one waveguiding layer and at least one subwavelength periodic grating layer; and upper and lower cladding layers immediately adjoining respective upper and lower surfaces of said WGS and having refractive indices lower than a lowest-index one of said waveguiding layers, incident radiation propagating through one of said upper and lower cladding layers toward said WGS; wherein said WGS is configured for peak reflection of said incident radiation at a peak reflection frequency; and wherein a cumulative thickness of said waveguiding layers is less than one tenth of a free space wavelength of the incident radiation at said peak reflection frequency divided by an average refractive index of said waveguiding layers.