Patent ID: 6711311
Filing Date: 2004-03-23
Classification: G02B

Abstract:
A polarization beam splitter/combiner for splitting a non-collimated beam of light into first and second sub-beams of orthogonal polarization comprising:a first port for launching the beam of light into the polarization beam splitter/combiner in a forward direction; a first uniaxial crystal optically coupled to the first port for separating the beam of light into the first and second sub-beams, which propagate along diverging o-ray and e-ray paths, respectively, the first crystal being made of a first material, having a first thickness and a first birefringent axis; a second uniaxial crystal having an e-ray path and an O-ray paths such that the e-ray path of the second uniaxial crystal is optically coupled with the O-ray path of the first uniaxial crystal and the O-ray path of the second uniaxial crystal is optically coupled with the e-ray path of the first uniaxial crystal, the second crystal being made of a second material, having a second thickness and a second birefringent axis, which is non-parallel to the first birefringent axis; and a second and a third port optically coupled to an end face of the second uniaxial crystal for outputting the first sub-beam and the second sub-beam, respectively, with a spatial separation therebetween in the forward direction, wherein an optical path length difference between the first sub-beam and the second sub-beam is negated or predetermined by the first and second materials, and the first and second thicknesses.