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. 02, 1991
Filed:
Jul. 18, 1989
Applicant:
Inventor:
Tadashi Ohtaka, Katsuta, JP;
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G21K / ;
U.S. Cl.
CPC ...
250306 ; 250307 ; 250310 ; 2503 / ; 2503 / ;
Abstract
An electron microscope eliminates external ducting for evacuation by interlinking the interiors of a sample chamber for a sample, a casing for electron lenses and a chamber for an electron gun. Those interiors form a closed space with an evacuation path extending therethrough and are evacuated by evacuation means a vacuum pump connected to the sample chamber. The electron lenses are contained within sealed modules and the evacuation path passes between the sides of those modules and the internal walls of the casing. The resulting structure may be enclosed in substantially unbroken magnetic shielding.