Patent ID: 6987908

Claim:
A grating dispersion compensator, comprising: a substrate including a top surface; a dielectric grating layer formed on the top surface of the substrate, the dielectric grating layer having an index of refraction that changes to define at least one grating period; a planar waveguide formed on the dielectric grating layer, the planar waveguide including: an input/output (I/O) surface for coupling optical signals both into and out of the planar waveguide; and a longitudinal axis normal to the I/O surface; and a passivation layer formed on the planar waveguide; wherein; the dielectric grating layer optically couples to the optical signals propagating along the planar waveguide from the I/O surface to retroreflect the optical signals back along the planar waveguide toward the I/O surface; and each grating period of the at least one grating period of the dielectric grating layer is a first predetermined function of position along the longitudinal axis.