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:
Sep. 25, 1984
Filed:
Jul. 28, 1981
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ; H01J / ; H01J / ;
U.S. Cl.
CPC ...
313412 ; 313413 ; 313414 ; 313431 ; 313440 ;
Abstract
An improved in-line type electromagnetic focusing cathode-ray tube which comprises magnetic yokes, a focusing magnetic field generating permanent magnet, a deflecting magnetic field control element and a cup-shaped spacer member for separating the magnetic yokes from the deflecting magnetic field control element. The deflecting magnetic field control element is disposed at a distance l.gtoreq.0.26 D from an end of the magnetic yoke closest to a fluorescent screen, where D is an outer diameter of the magnetic yoke, so that a beam spot on the fluorescent screen has substantially circular shape to attain an excellent focusing characteristic.