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. 30, 2004
Filed:
Aug. 30, 2002
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B23K 1/000 ;
U.S. Cl.
CPC ...
B23K 1/000 ;
Abstract
When determining the presence of foreign particles in a processing chamber by radiating a laser beam inside a processing chamber and detecting scattered light from foreign particles within the processing chamber, the detection of scattered light is performed using a detecting lens having a wide field angle and deep focal depth. Accordingly, the detection of foreign particles floating in the processing chamber can be performed across a wide range, and with uniform sensitivity, with a detecting optical system having a simple constitution.