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. 21, 1985
Filed:
Jun. 04, 1982
Masaaki Tamatani, Fujisawa, JP;
Nobuyuki Tsuda, Kawasaki, JP;
Norio Koike, Fukaya, JP;
Sakae Ajiro, Fukaya, JP;
Tokyo Shibaura Denki Kabushiki Kaisha, Kawasaki, JP;
Abstract
A projection type green cathode ray tube (CRT) with improved brightness despite an increase in the temperature of the faceplate, a method for manufacturing a phosphor screen adopted therein, and a projection video device which utilizes the projection type green CRT. The phosphor screen of the CRT is formed of a cerium-activated calcium sulfide phosphor which contains 0.01 to 0.3 mol% of cerium. According to the method for manufacturing the phosphor screen, the cerium-activated calcium sulfide phosphor is precipitated in a 0.3 to 5% aqueous solution of water glass based on weight. The aqueous solution does not contain barium ions. The projection video device includes the green CRT, a red CRT having a phosphor screen which is formed of an europium-activated yttrium oxide phosphor, and a blue CRT having a phosphor screen which is formed of a silver-activated zinc sulfide phosphor. Brightness of images is improved and does not substantially change over time.