Patent ID: 7081996
Filing Date: 2006-07-25
Classification: G02B

Abstract:
1. An isolated polarizing optical beam splitter/combiner capable of operating as a combiner for combining orthogonally polarized beams of light into a single port in a combining direction, and capable of operating as a splitter for splitting a beam of light into orthogonally polarized beams of light to spatially separated ports in a splitting direction comprising: a first port for launching a beam of light into the splitter/combiner when operating as a splitter, and for outputting a combined beam of light from the splitter/combiner when operating as a combiner; second and third spaced apart ports for launching orthogonally polarized beams of light into the splitter/combiner for combining and outputting the first port when operating as a combiner, and for outputting orthogonally polarized beams of light, which were input together at the first port, when operating as a splitter; a first polarization beam splitter optically coupled to the first port, oriented to provide different optical paths for two orthogonally polarized beams of light; a second polarization dependent beam steering means optically coupled to the second and third ports, oriented to provide different optical paths for two orthogonally polarized beams of light; a non-reciprocal rotator between the first polarization beam splitter element and at least an element of the second polarization dependent beam steering means for rotating a polarization of each of two orthogonal beams of light and maintaining the orthogonal relationship between them when passing therethrough in one direction, while having substantially no cumulative effect on the polarization of the two orthogonal beams of light when passing in an opposite direction, said non-reciprocal rotator adapted to be driven for transmission in a selected combining direction or a splitting direction, wherein, when operating as a combiner and driven in the combining direction, the non-reciprocal rotator permits light to propagate from the second and third ports simultaneously to the first port, and prevents light from coupling from the first port to the second and third ports, and wherein, when operating as a splitter and driven in the splitting direction, the non-reciprocal rotator permits light to propagate from the first port simultaneously to the second and third ports, and prevents light from coupling from the second and third ports to the first port.