Wavelength selection switch including a switching module having a liquid crystal phase array, a polarizer and a liquid crystal on silicon

An optical communication system having a wavelength selective switch (WSS) apparatus, the WSS apparatus comprising:

• a plurality of optical ports configured to emit input light beams to a switching module and receive output light beams from the switching module;
• and
• the switching module configured to receive the input light beams from the plurality of optical ports and selectively divert a predetermined wavelength component of the input light beams to continue to propagate to the plurality of optical ports by reflecting the predetermined wavelength component therefrom while keeping other wavelength components of the input light beams from propagating by controlling the voltage applied to the switching module and/or a polarization of light, the switching module comprising:
• a polarization modulation element that includes a one-dimensional array of a plurality of liquid crystal (LC) pixels;
• a polarizer that is configured to attenuate the input light beams output from the polarization modulation element and allow only a desired polarization of the input light beams to enter a steering element;
• and
• the steering element that includes a two-dimensional array of a plurality of active matrix liquid crystal (AMLC) pixels,
• wherein, in a horizontal direction, the plurality of LC pixels in the polarization modulation element are optically matched with the AMLC pixels in the steering element in such a way that the ratio of the number of the plurality of LC pixels to the number of the LCOS pixels is a predetermined ratio,
• wherein the AMLC pixels include at least one selected from the group consisting of a silicon backplane, a polysilicon backplane and an amorphous silicon backplane,
• wherein a polarization of the polarization modulation element differs from a polarization of the polarizer while the polarization of the polarizer is the same as a polarization of the LCOS phase array,
• wherein the LC phase array in combination with the polarizer, during a period of switching, blocks the output light beams reflected from the LCOS phase array from propagating to the plurality of optical ports.