Patent ID: 6882776

Claim:
An apparatus, comprising: a semiconductor material; an optical path through the semiconductor material, the optical path optically coupled to receive an optical beam; and an optical filter disposed in the semiconductor material, the optical path including the optical filter, the optical filter including a plurality of Bragg gratings disposed in the semiconductor material optically coupled to receive the optical beam, each of the plurality of Bragg gratings having a different Bragg wavelength, the optical beam to be directed from the optical filter with a non-uniform spectral response in response to the plurality of Bragg gratings, wherein each of the plurality of Bragg gratings includes a plurality of perturbations of a refractive index in the semiconductor material along the optical path, wherein the plurality of perturbations of the refractive index are provided with regions of silicon and polysilicon disposed in the semiconductor material along the optical path of each one of the plurality of Bragg gratings.