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:
Sep. 20, 2011
Filed:
Jun. 29, 2010
Applicants:
Koji Hirata, Yokohama, JP;
Takanori Hisada, Yokohama, JP;
Masahiko Yatsu, Fujisawa, JP;
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
G03B 21/14 (2006.01); G03B 21/28 (2006.01);
U.S. Cl.
CPC ...
Abstract
A projection type image display apparatus includes an image display element, and a projection optical unit, which is configured to project an image displayed on the image display element, enlargedly, upon a screen. The projection optical unit includes a lens group, which is configured to compensate an distortion on an image surface on the screen, a mirror for compensating a trapezoidal distortion on the screen. The mirror reflects lights emitted from the lens group, so as to project upon the screen obliquely.