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:
Aug. 05, 2003
Filed:
Aug. 30, 2000
Michio Kohno, Utsunomiya, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
An exposure apparatus wherein a first object is illuminated with slit-like exposure light while the first object and a second object are scanningly moved at a speed ratio corresponding to a projection magnification of a projection optical system such that a pattern of the first object is projected onto the second object through the projection optical system. The apparatus includes an illuminating device for illuminating a mark provided on the first object side with light having the same wavelength as that of the exposure light, wherein light from the mark is incident on the projection optical system whereby a revolutionally asymmetric aberration of the projection optical system due to an exposure is corrected or reduced.