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:
Nov. 20, 2012
Filed:
Oct. 12, 2007
Koji Hirata, Yokohama, JP;
Masahiko Yatsu, Fujisawa, JP;
Takanori Hisada, Yokohama, JP;
Masayuki Ohki, Kokubunji, JP;
Koji Hirata, Yokohama, JP;
Masahiko Yatsu, Fujisawa, JP;
Takanori Hisada, Yokohama, JP;
Masayuki Ohki, Kokubunji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A projection display system comprising a projection display unit including a light source, an image display element, a lighting optical system irradiating a beam of light on the image display element, and a projection optical system projecting an image light from the image display element toward a screen. The projection optical system including a lens group composed of a plurality of lens elements arranged in order toward the screen from the image display element and symmetrically with respect to an optical axis, and a reflecting mirror shaped to be axial-asymmetrical with respect to the optical axis. The projection display system further comprises a screen. The projection display unit projects the image light onto a projection plane of the screen to display an image.