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:
Oct. 12, 1993
Filed:
Aug. 30, 1991
Applicant:
Inventors:
Masataka Koga, Katsuta, JP;
Toyoharu Okumoto, Katsuta, JP;
Hiromi Yamashita, Katsuta, JP;
Katuo Kawachi, Katsuta, JP;
Yukio Okamoto, Sagamihara, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ; H01J / ;
U.S. Cl.
CPC ...
250281 ; 250282 ; 2502521 ;
Abstract
In the analysis of a specimen gas for at least one impurity, the specimen is fed to a microwave-induced plasma and the plasma is analyzed for the impurity. The plasma is formed by gases fed to it via an inner tube and an outer tube around said inner tube. The specimen is fed in undiluted form via the inner tube and a second gas which may be a standard gas is fed via the outer tube. The specimen gas and the second gas have compositions which are the same as to at least 75% by volume, e.g. are both air. A variety of analysis processes is made available.