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:
Jul. 17, 1984
Filed:
Dec. 09, 1981
Hitachi, Ltd., Tokyo, JP;
Abstract
A color television picture tube of three in-line gun type wherein a ring-shaped ferrite permanent magnet or magnets are disposed around a neck portion of the tube, at least a pair of mutually-opposing pole pieces made of highly permeable magnetic material are provided within the tube neck portion as a part of the gun assembly so as to be magnetized by the ring magnet or magnets and to form an electron beam magnetic focusing lens system. In the picture tube, the pole pieces are each of a substantially elliptical cross section as viewed from a plane perpendicular to the tube axis, and spaces are provided between an inner wall of the tube neck portion and the pole pieces to accommodate support rods for gun assembling. There are selected to fall in particular ranges the ratio of the outer diameter to inner diameter of the permanent magnet, the ratio of the thickness to inner diameter thereof, the ratio of the thickness to gap length between the opposing pole pieces, and the ratio of the tube-axial length of the pole piece disposed on the side of a phosphor screen to the tube-axial length of the pole piece disposed on the side of cathode electrodes.