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:
Feb. 02, 1988
Filed:
Aug. 26, 1985
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In a color picture device having a color picture tube, three electron guns for emitting electron beams are arranged in a neck section of the tube. A shadow mask, having a number of apertures, is arranged opposing a phosphor screen of a panel section of the tube. Convergence yokes for correcting misconvergence of the three electron beams are arranged around the neck section. A convergence electrode for converging the three electron beams over the entire screen is arranged in the neck section at the ends of the guns closer to the phosphor screen. The convergence electrode has three pairs of pole pieces each of which is formed of a magnetic substance with high permeability and is arranged in the neck section so as to surround the electron beam between the pole pieces. The length Wp of each pole piece along the tube axis is about two times or more the distance G between the pole pieces, and the length Wp is about twice the thickness Wy of the convergence yoke along the tube axis. Thus, the leakage flux from the pair of pole pieces along the tube axis is 20% or less of the total magnetic field generated by the convergence yoke.