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. 30, 1977
Filed:
Aug. 09, 1976
Applicant:
Inventors:
Shoji Kamimura, Katsuta, JA;
Yasushi Saito, Mito, JA;
Assignee:
Hitachi, Ltd., Tokyo, JA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
250311 ; 250397 ;
Abstract
A condenses lens system condenses an elctron beam onto a specimen. The electron beam thus transmitted through the specimen is magnified by a magnifying lens system. The magnified electron beam is projected onto a fluorescent screen, and the image of the specimen is visually observed. The quantity of electrons per unit area in the magnified electron beam is detected by an electron beam detector. In response to the detected signal, the condenser lens system is controlled so as to make constant the quantity of electrons per unit area in the magnified electron beam.