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. 20, 2003
Filed:
Feb. 20, 2001
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A method for producing an oxide cathode including a sleeve containing a heater coil, a cathode substrate provided on one end of the sleeve, and an emissive material layer formed by thermally decomposing an alkaline earth metal carbonate layer adhered onto the cathode substrate, which method includes adhering the alkaline earth metal carbonate onto the cathode substrate so that it has a bulk density of 0.5 to 0.8 g/cm , then pressing it so that the bulk density becomes not more than 0.9 g/cm , and then thermally decomposing it in vacuum. Accordingly, an oxide cathode in which the current density distribution of emission electrons is smooth and an electron emission characteristic is not deteriorated when operated for a long time is realized, and a method for producing a cathode-ray tube with high resolution in which moire is invisible is provided.