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. 02, 1998
Filed:
Sep. 03, 1996
Masahiko Sukeno, Hyogo, JP;
Takashi Watanabe, Osaka, JP;
Matsushita Electronics Corporation, Osaka, JP;
Abstract
An in-line color picture tube compensates for the distortion in the illuminated spot at the peripheral portion of the screen in a horizontally oblong shape. In particular, with an increase in the beam diameter under large current, or flattening of the panel or increase in the deflection angle, the beam distorted easily. However, such distortion is made to be small by providing a quadrupole lens with strong power. The in-line color picture tube has an electron gun comprising three cathodes that are in-line arranged in horizontal direction, a control electrode, an accelerating electrode and a focusing electrode system. The focusing electrode system comprises a couple of focusing electrodes having the facing portion on which non-circular beam through holes are provided. A predetermined focus voltage is applied to the first focusing electrode. A voltage changing in accordance with a deflection angle of the beam is applied to the second focusing electrode. A beam through holes that are oblong vertically are provided on the control electrode facing the cathode; and the beam through holes that are oblong horizontally are provided on the control electrode facing the accelerating electrode.