OPTICAL MULTIPLEXER AND DEMULTIPLEXER

摘要

Optical multiplexer and demultiplexer. Optical multiplexers and demultiplexers utilize interference filters and optical gratings. It is the object of the invention to reduce the losses caused by the use of gratings and filters. This is achieved by the substantially loss-free conversion of unpolarized light into linearly polarized light, so that the efficiency of the filters and gratings is improved. Furthermore, noise is suppressed which is caused by fluctuations in the degree of polarization of unpolarized light because filters and gratings have different characteristics for the different polarization directions.