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. 18, 2001
Filed:
Nov. 04, 1999
Hitachi, Ltd., Tokyo, JP;
Abstract
A color cathode ray tube having an electron gun including a beam forming region for generating a plurality of electron beams from cathodes and directing the plurality of electron beams toward a phosphor screen along initial paths in a horizontal plane, and a main lens for focusing the plurality of electron beams on the phosphor screen. The main lens including a final lens configured so that the plurality of electron beams are focused in both horizontal direction and a vertical direction with outer electron beams among the plurality of electron beams being deflected toward a trajectory of a center electron beam among the plurality of electron beams, and a lens strength thereof being weakened with an increase in an amount of deflection of the plurality of electron beams. The color cathode ray tube further includes at least one correction lens for curvature of an image field is located between the final lens and the beam forming region, and for focusing the plurality of electron beams in both the horizontal and vertical directions and weakening focusing action on the plurality of electron beams according to the increase in an amount of deflection of the plurality of electron beams. The at least one correction lens has an electrode configuration in which trajectories of outer electron beams among the plurality of election beams are deflected one of toward and away from a trajectory of a center electron beam among the plurality of electron beams according to the increase in an amount of deflection of the plurality of electron beams.