Patent ID: 6803972
Filing Date: 2004-10-12
Classification: G02B,G02F,H04N

Abstract:
A polarization conversion system for converting incident light having at least a first and second polarization, to light of one of the first and second polarizations, the polarization conversion system comprising:an input side at which the incident light enters; an output side at which light of one of the first and second polarizations exits; a polymer based reflective polarizing material disposed between the input and the output sides, in communication with the incident light for transmitting light on one of the first and second polarizations and reflecting the other; a reflector for reflecting the reflected light from the polymer based reflective polarizing material; a light block disposed on the input side for blocking the incident light from communication with the reflective means; a polarization convertor for shifting the polarization of the reflected light to that of the transmitted light; a holder structure incorporating retaining means for acceptance of the polymer based reflective polarizing material, the reflector, the polarization convertor, and the light block and for containing them in the desired arrangement; whereby the polymer based reflective polarizing material, the reflector, the polarization convertor, and the light block are arranged such that the transmitted light of one of the first and second polarizations exits the output side, and where the reflected light is directed towards the reflector which directs it towards the polarization convertor which shifts the polarization of the reflected light to that of the transmitted light before exiting the output side; and a transmissive wedge having an input and output side corresponding to the input and output sides of the polarization conversion system, and further having a polarization side and a reflecting side, and wherein the polymer based reflective polarizing material is affixed to the polarization side, the reflector is affixed to the reflecting side, the light block is affixed to the input side, and the polarization converter is affixed to the output side.