High emissivity cold cathode ultrastructure
US4916356A · kind A · utility
47Cited by
9References
8Claims
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Key dates
| Filing date | Sep 26, 1988 |
| Grant date | Apr 10, 1990 |
| Priority date | — |
| Expiry date | Sep 26, 2008 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J1/304
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A high emissivity cold cathode has alternating cylindrical tube layers, deposited by vapor deposition, of a refractory metal such as niobium and a refractory insulating material such as alumina. The metal layers have a thickness of less than or about 1,000 angstroms such that the electric field strength at the exposed end is sufficient, in combination with a low work function metal to emit electrons when a voltage of about 2,000 volts is applied.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.