Patent ID: 6792175
Filing Date: 2004-09-14
Classification: G02B,G02F

Abstract:
Apparatus for optically switching light from an input array comprising a plurality of light sources to an output array comprising a plurality of light receivers; wherein said apparatus is adapted to allow light from any selected light source to be switched to any selected light receiver; and wherein said apparatus is adapted to allow light from any or all of the light sources to be thus switched independently and simultaneously; and wherein said apparatus is adapted to allow each of the light receivers thus to receive light from zero, one, several, or all of the light sources; said apparatus comprising:(a) a series of input polarization-dependent angular deflectors, wherein the angle by which each of said input deflectors deflects incident light is a function of the direction of polarization of the light incident on said deflector; and (b) an array of input polarization control elements associated with each said input deflector, wherein each said input array comprises one input polarization control element corresponding to each light source, and wherein each said input polarization control element controls the degree, if any, to which the direction of propagation of light transmitted through said input polarization control element is altered; wherein:(c) said input polarization control arrays and said input deflectors are positioned so that the first said input polarization control array is adapted to transmit light from the light sources through said input polarization control elements of the first said input polarization control array to the first said input deflector; and so that each subsequent said input polarization control array is adapted to transmit light from the preceding said input deflector through said input polarization control elements of said subsequent input polarization control array to said input deflector associated with said subsequent input polarization control array; and so that the last of said input deflectors is adapted to transmit light to the light receivers; and wherein:(d) said apparatus is adapted to allow the switching of light from any selected light source to any selected receiver, by using said input polarization control arrays to control the direction of polarization of the light from the selected light source imposed by said input polarization control elements as the light enters each of said input deflectors, so that the net angular deflection of the light caused by all said input deflectors, which is a function of the directions of polarization of the light as it passes through each of said input deflectors, causes the light to be directed to the selected receiver.