Dynamic spectral equalizer and wavelength selective switch having extremely low polarization dependent loss and polarization mode dispersion

摘要

An optical system according to the present invention includes a beam polarization combiner for receiving first and second sets of input beams, and a reflective spatial light modulator having a plurality of individually activated modulating elements each corresponding to a respective one of the different wavelengths of the input beams. Each input beam is directed at a modulating element of corresponding wavelength with input beams of the first and second sets impinging upon the modulating element from respective first and second incoming paths. Each modulating element selectively changes the input beams such that the outgoing path for each reflected beam of each set is superimposed on the incoming path for the other set. The beam combiner receives the reflected sets of beams and directs them in different directions based upon their polarization. The optical system may be used in a wavelength selective switch or a dynamic spectral equalizer.