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:
Aug. 07, 2001
Filed:
Jun. 06, 2000
Applicant:
Inventors:
Ara Chutjian, La Crescenta, CA (US);
Murray R. Darrach, Arcadia, CA (US);
Otto J. Orient, Glendale, CA (US);
Assignee:
California Institute of Technology, Pasadena, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J 4/914 ;
U.S. Cl.
CPC ...
H01J 4/914 ;
Abstract
The present invention provides an improved electron ionizer for use in a quadrupole mass spectrometer. The improved electron ionizer includes a repeller plate that ejects sample atoms or molecules, an ionizer chamber, a cathode that emits an electron beam into the ionizer chamber, an exit opening for excess electrons to escape, at least one shim plate to collimate said electron beam, extraction apertures, and a plurality of lens elements for focusing the extracted ions onto entrance apertures.