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:
Jul. 12, 2011
Filed:
Jun. 07, 2007
Atsushi Okuyama, Tokorozawa, JP;
Yu Yamauchi, Utsunomiya, JP;
Takashi Sudo, Utsunomiya, JP;
Ryota Kadowaki, Utsunomiya, JP;
Atsushi Okuyama, Tokorozawa, JP;
Yu Yamauchi, Utsunomiya, JP;
Takashi Sudo, Utsunomiya, JP;
Ryota Kadowaki, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
An optical system for image projection is disclosed which is capable of improving contrast while suppressing reduction of light amount. The optical system includes a converging optical system, and a polarization beam splitting surface transmitting an incoming light flux having a first polarization direction from the converging optical system, to introduce it to the image-forming element and causing light having a second polarization direction, of an outgoing light flux from the image-forming element, to proceed to a projection optical system. In a first cross-section parallel to a normal to the polarization beam splitting surface, the converging optical system has a configuration causing an incident angle on the splitting surface of a light ray passing through a barycenter of intensity distribution of the outgoing light flux to be larger than an incident angle thereon of a light ray passing through a barycenter of intensity distribution of the incoming light flux.