Optical receiver and demultiplexer for free-space wavelength division multiplexing communications system

摘要

A free-space wavelength division multiplexing system (10) is provided having a demultiplexer and receiver (68) arrangement. The demultiplexer and receiver arrangement may be based on a rotatable interference filter (46a). A desired wavelength can be selected by adjusting the angle of the interference filter (46a) with respect to the incoming light beam. Alternatively, the demultiplexer and receiver arrangement may be based on a diffraction grating. Multiple wavelengths of light are diffracted at different angles, which spatially separates each wavelength in the system. A corresponding multiple-element linear photodetector array is used to receive the spatially separated optical signals. <IMAGE>