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. 24, 1995
Filed:
Nov. 22, 1993
Applicant:
Inventors:
Masayoshi Misono, Chiba, JP;
Atsushi Tsuruoka, Mobara, JP;
Assignees:
Hitachi, Ltd., Tokyo, JP;
Hitachi Device Engineering Co., Ltd., Chiba, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
313414 ; 313449 ; 313460 ;
Abstract
In an electron gun wherein an electric field which is established between the axially opposed parts of a pair of electrodes forming a main lens has a rotationally-asymmetric distribution; electric-field correcting plates (54, 65 in FIG. 1B) are provided in the respective electrodes (5, 6) so as to render a lens action on electron beams substantially rotationally symmetric. The electron beams form smaller spots on the fluorescent screen of a cathode-ray tube than in the prior art.