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:
Jun. 24, 2008
Filed:
Jun. 24, 2004
Mitsuhiro Wada, Kadoma, JP;
Mitsuhiro Wada, Kadoma, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A projection lens that, though designed for right projection, shows good aberration performance and can realize specifications required for a projection display apparatus, such as a low F number, a wide angle, a long back focus, and a high relative illumination, with a rational configuration is provided. A projection lensof the present invention for magnifying and projecting an optical image formed on a spatial light modulator (disposed near an image plane) onto a screenis constituted by a front lens groupand a rear lens groupthat are arranged in this order from the screenside toward the image planeside. The rear lens groupis provided with a aperture stopthat is eccentric with respect to an optical axiscommon to the front lens groupand the rear lens group. Focus adjustment is performed by moving the rear lens groupin a direction of the optical axiswithout rotating it.