Cathode for electron tube and method for manufacturing the same
US7138754B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 19, 2002 |
| Grant date | Nov 21, 2006 |
| Priority date | — |
| Expiry date | Oct 1, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J9/04
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An oxide cathode for an electron tube and a method for manufacturing the oxide cathode are provided. In the oxide cathode including a sleeve for a heater, a metal substrate formed on the top of the sleeve, and an electron emission material layer coated on the metal substrate, the electron emission material layer is formed by coating a carbonate paste containing an alkaline earth metal carbonate, an organic blowing agent, and a vehicle on the metal substrate by screen printing, and thermally treating the coated carbonate paste. Picture quality degradation due to a Moire phenomenon is reduced by coating the carbonate paste by screen printing to provide an even cathode surface, and degradation of the cathode by Joule heat is reduced, thereby improving electron emission and lifespan characteristics of the cathode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.