Patent ID: 8358398

Claim:
An optical device configured to perform switching and attenuation of an input beam, comprising: a liquid crystal (LC) structure for conditioning the polarization state of incident light and disposed in an optical path of an input beam and optical paths of output beams generated from the input beam, the LC structure having, a first light-conditioning LC region positioned in the optical path of the input beam, a second light-conditioning LC region positioned in an optical path of a first output beam, a third light-conditioning LC region positioned in an optical path of a second output beam, and a control electrode that is controlled to be set at one of multiple bias levels and is arranged to simultaneously apply the same bias to the first, second and third light-conditioning LC regions; a first electrode that is arranged to apply a first fixed reference bias to the first and second light-conditioning LC regions; a second electrode that is arranged to apply a second fixed reference bias to the third light-conditioning LC region; and a beam polarization separator disposed in the optical path of the input beam and configured to generate the output beams from the input beam based on a polarization state of the input beam.