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:
Dec. 16, 2003
Filed:
May. 21, 2002
Aki Nakajo, Yokohama, JP;
Makoto Iida, Kawasaki, JP;
Hiroki Kuramoto, Yokohama, JP;
Masakazu Ogawa, Yokohama, JP;
Tatsumi Hasebe, Hichisou, JP;
Yoshie Kodera, Chigasaki, JP;
Sadayauki Nishimura, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a projector, the precision of color synthesis is improved and the generation of vertical stripes in the projected image is suppressed by a dichroic prism used for color synthesis that employs at least the following aspects. (1) The dichroic prism is formed using triangular prisms, in which projections or grooves are provided that have two faces parallel to two pasted faces of the triangular prisms, the projections or grooves being integrally injection-molded on faces of the triangular prisms that are substantially perpendicular to the light beam (i.e., the faces through which no light beam passes); (2) the dichroic prism is positioned using marks on the pasted faces of the triangular prisms; or (3) the dichroic prism is formed by engaging triangular prisms in which recesses or projections are formed.