Patent ID: 6452724
Filing Date: 2002-09-17
Classification: F21V,G02B

Abstract:
A polarizer apparatus for efficiently physically decoupling two orthogonal polarizations of a source light beam within a visible spectrum or near visible spectrum into two generally polarized beams and recapturing at least one of the two beams, the apparatus comprising:a light source for emitting a source light beam within the visible spectrum or near visible spectrum; a generally parallel arrangement of thin, elongated elements disposed in the source light beam, the elements having a pitch of 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; and a light recapture means separate from the light source and disposed at an orientation in the transmitted beam for intercepting and redirecting substantially all of the transmitted beam so that the transmitted beam is not directed back into the light source; a polarization reorientation means disposed in at least one of the reflected or transmitted beams for changing the polarization orientation of substantially all of the reflected or transmitted beam so that both the reflected and the transmitted beams have generally the same polarization, thereby substantially converting all the source light beam. to a single polarization.