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:
Oct. 03, 2006
Filed:
Mar. 07, 2005
Jun Nishikawa, Tokyo, JP;
Nobuhiko Nishiki, Kanagawa, JP;
Yasunori Kuratomi, Kanagawa, JP;
Tetsuya Kita, Kanagawa, JP;
Takaaki Iwaki, Tokyo, JP;
Jun Nishikawa, Tokyo, JP;
Nobuhiko Nishiki, Kanagawa, JP;
Yasunori Kuratomi, Kanagawa, JP;
Tetsuya Kita, Kanagawa, JP;
Takaaki Iwaki, Tokyo, JP;
Sony Corporation, , JP;
Abstract
A projection optical system and an image projection apparatus that are small in size and can achieve projection with a wide angle while a good image forming performance is assured includes a first lens group having a negative refracting power and a second lens group also having a negative refracting power. The first and second lens groups are arranged in order from the projection side. The first lens group includes a negative meniscus lens that has a concave surface directed to the projection side and formed as an aspherical reflecting surface.