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. 20, 1988
Filed:
Oct. 21, 1986
Applicant:
Inventors:
Norio Koike, all of, Fukaya, JP;
Takeo Itou, all of, Fukaya, JP;
Hidemi Matsuda, all of, Fukaya, JP;
Mitsuhiro Oikawa, Yokohama, JP;
Assignee:
Kabushiki Kaisha Toshiba, Kawasaki, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
313467 ; 2523 / ; 25230165 ; 2523 / ; 313468 ;
Abstract
In a cathode ray tube with a phosphor screen containing a Zn type green emitting phosphor, e.g. ZnS, ZnCdS and Zn.sub.2 SiO.sub.4, the surface of the phosphor particle includes a surface area of (Co,Zn)O. The surface area is green colored to operate as a filter against incident light from outside the tube and reduces background brightness of picture images caused by excitation of scattering electrons. Thus, the contrast of the picture images rises. The contrast is further increased by Ni doped.