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. 13, 1981
Filed:
Feb. 01, 1979
Hideo Todokoro, Hinodemachi, JP;
Yoshio Sakitani, Ohimachi, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
In a field emission electron gun including heating means for heating an anode to prevent gas emission from the anode due to bombardment thereof by the electron beam emitted from the cathode, the present invention provides a field emission electron gun including first exhaust means for defining a first chamber including the cathode and for exhausting said chamber to vacuum, and second exhaust means separate from said first exhaust means defining a chamber including said anode heating means for exhausting said chamber to vacuum independently of the first exhaust means. This construction makes it possible to maintain the chamber including the cathode constantly in the high vacuum state.