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:
Jun. 30, 1981
Filed:
Jun. 02, 1978
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ;
U.S. Cl.
CPC ...
315 16 ;
Abstract
In an electron gun for cathode-ray tube comprising a lens system constructed by four cylindrical electrodes concentrically arranged apart from each other for focusing electron beams emitted from a cathode, these electrodes are applied with proper voltages so as to form a bipotential type focusing lens and a unipotential type focusing lens. Preferably, the length of the electrode in the unipotential type focusing lens lying at the cathode side is selected to be larger than a half of the inner diameter of the electrode.