Patent ID: 8422013

Claim:
An optical multiplexer/demultiplexer comprising: a primary reflective optical element and a secondary reflective optical imaging element in combination with a diffraction grating operating in a near Littrow configuration, said primary reflective optical element being a single one-piece optical element segmented into a parabolic section at the periphery of said primary reflective optical element and a pair of adjacent aspheric sections, said combination concentrating in a demultiplexing operation a diverging incoming multispectral beam and collimating said concentrated diverging incoming multispectral beam towards said grating, said combination functioning as a telescope to take the diffracted light from said grating and focus said diffracted light towards an output plane such that beams of different colored light arrive in parallel at said output plane to establish telecentricity, said combination functioning in a multiplexing operation to take differently colored light beams arriving at said output plane, focusing said differently colored light beams onto said grating and collimating the refracted light from said grating into a single multispectral output beam.