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:
Sep. 16, 2008
Filed:
Dec. 08, 2005
Yoshimasa Ohshima, Yokohama, JP;
Hisafumi Iwata, Hayama, JP;
Hiroyuki Nakano, Yokohama, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
There is disclosed a defect detecting apparatus that focuses a laser beam, irradiates it onto the surface of a sample to be examined, and detects a foreign substance/defect existing on the surface from the scattered light as a result of the irradiation of the beam onto the sample surface. In order to stably detect defects such as foreign substance, the defect detecting apparatus according to the invention is constructed to use a beam shape optical system by which the laser beam emitted from a laser source is shaped to change the illumination intensity from its Gauss distribution to a flat distribution so that the detected signal can be stably produced even if the relative position of a defect/foreign substance to the laser beam irradiation position is changed.