Patent ID: 10393968

Abstract:
A wavelength selective switch includes a plurality of optical ports, a polarization conditioning system, a dispersion system, and a switching system. The switching system includes at least one transmissive stage and a reflective polarization modulator. Each transmissive stage has a transmissional polarization modulator and a symmetrical beam polarization separator. The transmissional polarization modulator includes transmissive first cells each being configured to change a polarization orientation of an optical beam passing through the cell. The symmetrical beam polarization separator is configured to redirect the optical beam passing therethrough based upon its polarization. The reflective polarization modulator includes a birefringence section and a reflective section. The birefringence section includes controllable second cells each being configured to convert linear polarization of an optical beam passing therethrough to circular polarization and to independently and selectively convert circular polarization of the optical beam passing through the second cell to linear polarization.