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. 29, 2004
Filed:
Apr. 04, 2003
Saburo Sugawara, Tochigi, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A projector-type image display device includes a liquid crystal display device for forming an image, an illumination optical system for illuminating the liquid crystal display device with light from a light source, a projection optical system for projecting an image from the liquid crystal display device, and a diaphragm member disposed on at least one of the illumination optical system and the projection optical system. An aperture is formed in the diaphragm member, and the aperture has a shape such that the f-numbers at a plurality of directions from the at least one optical system are different f-numbers, according to contrast properties of each direction of the liquid crystal display device.