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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.:

US 7222965 B1

PDFFull Text
Expired
Date of Patent:
May. 29, 2007

Filed:

Aug. 11, 2004

Optical unit and a projection image display apparatus using the same

Applicants:

Masahiko Yatsu, Fujisawa, JP;

Tsutomu Nakashima, Yokohama, JP;

Inventors:

Masahiko Yatsu, Fujisawa, JP;

Tsutomu Nakashima, Yokohama, JP;

Assignee:

Hitachi, Ltd., Tokyo, JP;

Attorney:

Townsend and Townsend and Crew LLP

Primary Examiner:

W B Perkey

Assistant Examiner:

Rochelle Blackman

Int. Cl.
CPC ...
G03B 21/14 (2006.01); G03B 21/26 (2006.01); G03B 21/28 (2006.01); G03B 21/20 (2006.01); G02F 1/1335 (2006.01); G02B 5/30 (2006.01); G02B 27/28 (2006.01); G02B 27/14 (2006.01); G02B 27/12 (2006.01); H04N 5/74 (2006.01);
U.S. Cl.
CPC ...
Abstract

The present invention provides a projection image display technology capable of correcting astigmatism due to use of a polarized-beam splitter, thus ensuring high-resolution projection images. A wire-grid polarized-beam splitter (or the like) of a flat-plate-like structure is used as a polarized-beam splitter, and an astigmatism correction element, such as a cylindrical lens, is provided between the polarized-beam splitter and a projection lens unit.

Find Patent Forward Citations

Yatsu, Masahiko. (2007). Optical unit and a projection image display apparatus using the same (U.S. Patent No. 7222965). U.S. Patent and Trademark Office. https://idiyas.com/patent/badge/7222965

Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile

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