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:
Jul. 08, 2003
Filed:
Jan. 27, 2000
Applicant:
Inventors:
Samuel K. Doran, Wappingers Falls, NY (US);
Steven D. Golladay, Hopewell Junction, NY (US);
Assignee:
Nikon Corporation, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B23K 1/500 ; G01R 1/900 ;
U.S. Cl.
CPC ...
B23K 1/500 ; G01R 1/900 ;
Abstract
An automatic control servo system having a number of cascaded loops equal in number to the number of voltage sources applied to elements of a high-emittance electron source provides accurate and stable electron emission current control independently of beam energy and accommodates large differences in thermal mass between the elements of the electron source, as may be encountered in high-emittance, indirectly heated cathode electron sources. Individual loops of the system may be critically tuned independently of each other.