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:
Oct. 04, 2005
Filed:
Aug. 30, 2001
Satoshi Ouchi, Kamakura, JP;
Taro Imahase, Fujisawa, JP;
Nobuaki Kabuto, Kunitachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A projection-type video display apparatus has a polarizing beam splitter for matching light, which is outputted by a light source unit, to one of S polarizing light and P polarizing light, an optical characteristics switching element for electrically and periodically switching a wavelength band of light outputted by the polarizing beam splitter, a video display element, as a light valve element, for forming an optical image from light outputted by the light source unit, in accordance with a video signal, and a radiating unit for radiating a plurality of color light, which are sequentially outputted by the optical characteristics switching element, to the video display element, wherein light outputted by the video display element is incident on a projecting lens, and a light path from the light source unit to the projecting lens is U-shaped. Consequently, the projection-type video display apparatus becomes compact and has improved contrast.