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:
Dec. 02, 1997
Filed:
Dec. 02, 1996
Junichi Kimiya, Fukaya, JP;
Shigeru Sugawara, Saitama-ken, JP;
Eiji Kamohara, Fukaya, JP;
Kumio Fukuda, Fukaya, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
In a color cathode ray tube apparatus, a main electron lens unit for converging three in-line electron beams on a phosphor screen is formed of a plurality of electrodes, including at least first, second, and third electrodes, which are arranged from the cathode side toward the phosphor screen. An asymmetric electron lens, which horizontally diverges and vertically converges the electron beams, is formed on the cathode side in a lens effect region of a first electron lens composed of the second and third electrodes, and an asymmetric second electron lens, which has one effect with respect to the horizontal direction of the electron beams and another with respect to the vertical direction, is formed between the first and second electrodes, at the least. In this arrangement, the effects of the second lens to converge and diverge the electron beams in the horizontal and vertical directions, respectively, are enhanced, and the effects of the first electron lens are attenuated, depending on the deflection of the electron beams by means of a deflection yoke. Thus, the horizontal and vertical diameters of beam spots at the peripheral portion of a picture can be reduced.