Patent ID: 7013065

Claim:
A planar optical apparatus for setting the chromatic dispersion in an optical system, comprising: a waveguide input structure with a first free-beam region for transmitting a signal, a first phase grating, connected to the first free-beam region, for spatially separating the spectral components of the signal, a second free-beam region, connected to the first phase grating, for receiving the spatially separated spectral components of the signal, means for performing spatially dependent modification of a phase of the spatially separated spectral components of the signal in the second free-beam region, a second phase grating, connected to the second free-beam region, for combining the phase-modified spectral components of the signal, and a waveguide output structure with a third free-beam region attached to the second phase grating for transmitting the phase-modified signal, wherein the means for spatially dependent modification of the phase of the spatially separated spectral components includes a first phase plate that is moveably disposed in the second free-beam region.