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. 02, 1990
Filed:
Jan. 31, 1989
Hitachi, Ltd., Tokyo, JP;
Abstract
The disclosed relates to a convergence apparatus to be used for a single electron gun type cathode-ray tube, and relates to a convergence yoke to be used for the convergence apparatus. Each of two magnetic poles for generating a bipolar magnetic field is constituted by a first one of a plurality of core protrusions located on a horizontal or vertical axis and at least one pair of second ones of the plurality of core protrusions located at positions equiangularly and symmetrically deviated from the horizontal or vertical axis, and a ratio of an ampere turn of the coil wound on each of at least one pair of second core protrusions to an ampere turn of the coil wound on the first core protrusion is suitably changed. A firt magnetic auxiliary plate and a second magnetic auxiliary plate are provided on a first core protrusion constituting each of a first pair of magnetic poles and on a second core protrusion constituting each of a second pair of magnetic poles respectively. Each of the first and second magnetic auxiliary plates has a fork end projected along an axis perpendicular to a horizontal axis as well as a vertical axis. The first and second magnetic auxiliary plates have respective widths existing within an angular range symmetrically deviated by 45.degree. from the horizontal axis and within an angular range symmetrically deviated by 45.degree. from the vertical axis respectively. Each of the first and second magnetic auxiliary plates has a substantially Y-shaped and axisymmetrical form.