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. 21, 2011
Filed:
Mar. 11, 2008
Ryuhei Amano, Hirakata, JP;
Michihiro Okuda, Hirakata, JP;
Ryuhei Amano, Hirakata, JP;
Michihiro Okuda, Hirakata, JP;
SANYO Electric Co., Ltd., Moriguchi, JP;
Abstract
An imager is shifted with respect to an optical axis of a refractive optical system. Thereby, a throw distance of a projector is shortened. A wavelength-selective half wavelength plate for rotating a polarization direction of green light beams is disposed between a dichroic prism and the refractive optical system in such a manner that the polarization direction of the green light beams is in parallel to the shifting direction. Thereby, the green light beams are incident onto the refractive optical system as P-polarized beams, whereby a transmittance of the green light beams in the refractive optical system is increased, while suppressing lowering of the light amount of the green light beams, and color non-uniformity resulting from lowering of the light amount of the green light beams.