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. 16, 1996
Filed:
Apr. 19, 1995
Applicant:
Inventors:
Katsuyoshi Tsunoda, Shibukawa, JP;
Yoshinori Terui, Shibukawa, JP;
Assignee:
Denki Kagaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ; H01J / ;
U.S. Cl.
CPC ...
2504 / ; 313336 ; 313310 ; 313311 ;
Abstract
A thermal field emission electron gun has a thermal field emission cathode and a suppressor electrode wherein the thermal field emission cathode comprises a single crystal tungsten needle of an axis direction of <100> and a coating layer composed of zirconium and oxygen, and the suppressor electrode is composed of either titanium or an alloy including titanium as the major component, of which hydrogen content is 60 ppm or less. Electron beams can be stably obtained with good reproducibility in a short time.