Patent ID: 6882775

Claim:
An optical multiplexing/demultiplexing apparatus, comprising: an optical fiber; a collimator optically coupled to the optical fiber for collimating an optical signal from the optical fiber into a beam having circular cross section; at least one anamorphic pair of prisms optically coupled to the collimator at a side opposite to the optical fiber, wherein the at least one anamorphic pair of prisms is used to change the beam between the circular cross section and an elliptical cross section; a diffraction grating optically coupled to the at least one anamorphic pair of prisms at a side opposite to the collimator; a focusing lens optically coupled to the at least one anamorphic pair of prisms; and a plurality of optical devices optically coupled to the focusing lens at a side opposite to the at least one anamorphic pair of prisms.