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:
Sep. 15, 1992
Filed:
Feb. 13, 1992
Takeo Itou, Kumagaya, JP;
Hidemi Matsuda, Oomiya, JP;
Hajime Tanaka, Fujioka, JP;
Kazuhiko Shimizu, Fukaya, JP;
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Abstract
A color picture tube comprising an envelope including a front panel, a phosphor screen formed in the inner surface of the front panel, and an electron gun arranged in the envelope. The phosphor screen includes a light absorbing layer having a plurality of holes and phosphor layers formed in the holes so as to partially overlap the light absorbing layer. The transmittance T of the light absorbing layer, the ratio a of the area of a light emitting region in a portion where the light absorbing layer overlaps the phosphor layers to the area of the phosphor screen, the ratio b of the area of the light absorbing layer to the area of the phosphor screen, and the ratio r of the light emitting region in the holes to the area of the holes satisfy the following relational expression: 1/T.gtoreq.1/2{(rb/a)-[a/(1-b)r]}.