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:
Jan. 30, 2007
Filed:
Apr. 13, 2005
Kanjo Orino, Tokyo, JP;
Kanjo Orino, Tokyo, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
Disclosed is an illumination optical system having an imaging optical system for imaging a predetermined object plane upon an image plane, by use of light supplied from an integrator that functions to produce a plurality of light sources using light from a light source. In one preferred form of the invention, the imaging optical system includes, in an order from a light incidence side thereof, a first lens group having a positive power, a second lens group having a negative power, and a third lens group having a positive power, wherein the second lens group includes a concave lens at a light exit side thereof and wherein the third lens group includes a convex lens at a light entrance side thereof. The position of intersection between an optical axis of the imaging optical system and a principal ray of abaxial light is defined between the second lens group and the third lens group.