Patent ID: 6108131
Filing Date: 2000-08-22
Classification: F21V,G02B

Abstract:
A polarizer apparatus for efficiently producing a generally polarized light beam from a generally unpolarized source light beam having orthogonal first and second polarizations produced by a light source, the apparatus comprising:a generally parallel arrangement of thin, elongated elements configured for disposition in the source light beam, the elements having a pitch less than approximately 0.4 micrometers and providing means for interacting with electromagnetic waves of the source light beam to generally (i) transmit light having a polarization oriented perpendicular to the elements and defining a transmitted beam of a first polarization, and (ii) specularly reflect light having a polarization oriented parallel with the elements and defining a reflected beam of a second polarization;a light recapture means physically positioned in a different location from a light source and configured for disposition in at least one of the reflected or transmitted beams for intercepting and redirecting at least one of the beams so that the reflected beam is not directed back into the light source, the light recapture means being oriented to direct the reflected beam so that the reflected beam is not directed back into the arrangement of elements; anda polarization reorientation means configured for disposition in at least one of the reflected or transmitted beams for changing the polarization orientation of substantially all the reflected or transmitted beam so that both the reflected and transmitted beams have generally the same polarization, thereby substantially converting all the source light beam to a single polarization.