Patent ID: 7639911

Claim:
An optical device comprising: a cladding layer formed on a substrate; and an optical waveguide formed within the cladding layer, wherein the optical waveguide comprises a lower core layer, an upper core layer and an organic Bragg grating sheet located between the upper and lower core layers, the organic Bragg grating sheet comprises a residue layer and bars on the residue layer in which the residue layer has a thickness greater than zero and less than a thickness of the bars such that the thickness of the residue layer is adjusted to effectively control the effective refractive index of the entire organic Bragg grating sheet, the refractive index of the entire organic Bragg grating sheet is higher than the refractive indices of the upper and lower core layers, the organic Bragg grating sheet has a thickness not exceeding one half of the entire thickness of the upper and lower core layers, and the organic Bragg grating sheet has a higher refractive index than that of both the upper and lower core layers to reflect or transmit light having a predetermined wavelength.