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:
May. 03, 2011
Filed:
Jun. 08, 2007
Yu Yamauchi, Utsunomiya, JP;
Atsushi Okuyama, Tokorozawa, JP;
Hiroyuki Kodama, Utsunomiya, JP;
Takashi Sudo, Utsunomiya, JP;
Yu Yamauchi, Utsunomiya, JP;
Atsushi Okuyama, Tokorozawa, JP;
Hiroyuki Kodama, Utsunomiya, JP;
Takashi Sudo, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
An optical system for image projection is disclosed which is easy to be manufactured and designed and capable of projecting a bright image with high contrast. The optical system includes an illumination optical system introducing a luminous flux emitted from a light source to an image-forming element through an optical surface having a light-splitting function, and a projection optical system projecting the luminous flux from the image-forming element through the optical surface onto a projection surface. The illumination optical system includes a conversion system which respectively converts the widths of the luminous flux in first and second cross-sections into widths different from those before entering thereinto. Conversion rates in the first and second cross-sections are different from each other.