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:
Nov. 09, 2004
Filed:
Mar. 20, 2002
Ryoko Otomo, Saitama, JP;
Fuji Photo Optical Co., Ltd., Saitama, JP;
Abstract
A projection optical system is disclosed that includes six lens groups, four of which are positioned in pairs symmetrically about a stop. The second and fifth lens groups, in order from the object side, may be positioned symmetrically about the stop but are also adjustable asymetrically about the stop in order to adjust the magnification of the projection optical system. The first and sixth lens groups, in order from the object side, function to make the projection optical system substantially telecentric on both the object side and the image side, respectively. Also disclosed is a projection and light exposure apparatus that uses the projection optical system of the present invention. The projection and light exposure apparatus automatically detects the image magnification and, based on the detection result, adjusts the positions of the second and fifth lens groups G and G as a unit so as to maintain a specified magnification.