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:
Feb. 15, 2005
Filed:
Dec. 31, 2001
Kouji Yoshida, Adachi-ku, JP;
Kouji Yoshida, Adachi-ku, JP;
Nikon Corporation, Tokyo, JP;
Abstract
In view of a specific area having a characteristic surface state in a mark-formed area or a surrounding area thereof, an area calculation unit has a window having a dimension corresponding to the specific area scan the whole measurement area in order to obtain a quantity representing a surface state based on measured signals through the window, and then, by identifying a measured signal area corresponding to the specific area based on the quantity as a function of the window's position, extracts a measured signal area corresponding to the mark. And a position calculation unit performs computation such as pattern-matching on the signal area extracted, thereby detecting the position of the mark accurately and quickly.