The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 10, 2007
Filed:
Aug. 07, 2003
Kuo-yuin LI, Tainan County, TW;
Kuo-Yuin Li, Tainan County, TW;
Himax Technologies, Inc., Tainan, TW;
Abstract
The present invention relates to an illumination device of an LCD projection system. The illumination device comprises a light source, a quarter-wave retardation and a wire grid polarizer. The light source is used for providing light. The quarter-wave retardation is disposed near the light source. The wire grid polarizer is disposed parallel to the quarter-wave retardation, and is associated with the quarter-wave retardation to polarize the light from the light source. P-polarized light can pass through the wire grid polarizer. S-polarized light cannot pass through the wire grid polarizer, and is reflected to the quarter-wave retardation to become circular polarized light. The circular polarized light is reflected by a parabolic surface of the light source and passes through the quarter-wave retardation again to convert into p-polarized light. The converted p-polarized light can pass through the wire grid polarizer. Therefore, the illumination device of the invention can provide high-efficiency polarized light. The illumination device can achieve high polarization conversion efficiency, and can be manufactured easily to reduce costs.