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. 25, 1989
Filed:
Oct. 22, 1987
Applicant:
Inventor:
Yoshiaki Takahashi, Chiba, JP;
Assignees:
Hitachi, Ltd., Tokyo, JP;
Hitachi Device Eng. Co. Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ;
U.S. Cl.
CPC ...
313414 ; 313449 ; 315 15 ;
Abstract
In an electron gun apparatus for color cathode-ray tube, first and second focusing electrodes respectively for focusing electron beams emitted from three electron guns are disposed. Between the first and second focusing electrodes, a pair of third focusing electrodes for forming an axial-nonsymmetrical electron lens are also disposed. Mutually different dynamic voltages are supplied to the third focusing electrodes in accordance with the change in deflection angle of the electron beam. Owing to the above described structure, uniform resolution is obtained at both the central part and the peripheral part of the screen.