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:
Apr. 24, 1990
Filed:
May. 15, 1989
Masahiro Ito, Chiba, JP;
Satoru Endo, Mobara, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A method of fabricating an electrode of a color picture tube electron gun, the electrode having an aperture for passing an electron beam and having a recess formed in a surface of a single metal plate, comprises the steps of forming in the metal plate a laterally elongated through hole being substantially symmetrical with the axis of the electron beam pass aperture and having a major diameter in a longitudinal direction of the recess, before the recess is formed, forming the recess at a peripheral wall area of the laterally elongated through hole through a coining process, and forming the electron beam pass aperture by removing a wall portion of the through hole existing after completion of the coining process to form a through hole of a predetermined shape.