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:
May. 16, 2006
Filed:
Jun. 01, 2005
Norio Shimizu, Ibaraki, JP;
Fumiaki Nihei, Ibaraki, JP;
Toshio Uchikawa, Ibaraki, JP;
Matsushita Toshiba Picture Display Co., Ltd., Osaka, JP;
Abstract
The radius of curvature of the outer surface of a panel is 10,000 mm or more, and a shadow mask is made of a material containing 95% or more of iron. A sagging amount change curve along a curve Con the surface of the shadow mask, which a plane passing through a center Pof a useful area of the shadow mask and parallel to a tube axis and a major axis crosses, satisfies a particular Condition 1. Assuming that an intersection between the curve Cand a useful area end of the shadow mask is a major axis end PL, a distance from the center Pto the major axis end PL along a major axis is W, and a point on the curve Caway from the center Pby ⅔×W in the major axis direction is Pa sagging amount change curve along a curve Con the surface of the shadow mask, which a plane passing through the point Pand parallel to the tube axis and the minor axis crosses, satisfies a particular Condition 2. Consequently, a color picture tube can be realized, which has satisfactory visibility, and less degradation in color purity caused by doming while having a shadow mask made of an inexpensive material with satisfactory moldability.