US 7,468,844 B2
	Apparatus for adding red light to a polarized light system
Estill Thone Hall, Jr., Indianapolis, Ind. (US)
Assigned to Thomson Licensing, Boulogne Billancourt (France)
Appl. No. 10/589,117 PCT Filed Mar. 09, 2004, PCT No. PCT/US2004/007104 § 371(c)(1), (2), (4) Date Aug. 11, 2006, PCT Pub. No. WO2005/099277, PCT Pub. Date Oct. 20, 2005.
Prior Publication US 2007/0188865 A1, Aug. 16, 2007
Int. Cl. G02B 27/14 (2006.01); G02B 27/28 (2006.01)

U.S. Cl. 359—634  [359/502]

4 Claims

1. An apparatus for adding red light to a polarized light system comprising: a first white light source and a second white light source; a polarizing beam splitter for combining S-polarized-light from said first white light source and P-polarized light from said second white light source; a first multi-layer filter means for rotating the polarization state of green light from said first white light source to the P-polarization state; a second multi-layer filter means for rotating said first white light source red light to the P-polarization state and said second white light source red light to the S-polarization state; and a reflective cleanup polarizer for reflecting P-polarized-light back to respective said first and second white light sources and passing S-polarized-light for further processing.