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. 16, 1997
Filed:
Feb. 23, 1995
Applicant:
Inventors:
Gyu-nam Ju, Seoul, KR;
Jong-seo Choi, Anyang, KR;
Keun-bae Kim, Seoul, KR;
Kwang-min Lee, Suwon, KR;
Kwi-seok Choi, Seoul, KR;
Assignee:
Samsung Display Devices Co., Ltd., Kyungki-do, KR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01J / ;
U.S. Cl.
CPC ...
3133 / ; 313337 ; 313270 ;
Abstract
A cathode for an electron tube has a layer of electron-emissive substance containing alkaline earth metal carbonates having capillary crystals, to which 0.01-20.0 wt % of both a lanthanum (La) compound and a magnesium (Mg) compound or an La--Mg compound, based upon the weight of the alkaline earth metal carbonate, is added. The cathode enjoys full interchangeability with a conventional oxide cathode and a 15-20% longer lifetime.