Low-pressure discharge lamp
US5841222A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 1996 |
| Grant date | Nov 24, 1998 |
| Priority date | — |
| Expiry date | Nov 27, 2016 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/72
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A low-pressure discharge lamp of the invention is provided with a gas-tight discharge vessel (10) which contains an ionizable filling. Electrodes are arranged inside At least one of the electrodes has a tungsten coil (20.sub.A) which is electrically connected to current supply conductors (30.sub.A, 30.sub.A ') which extend to outside the discharge vessel (10). The coil (20.sub.A) has a central zone (21.sub.A) covered with an electron-emitting material (22.sub.A) and, on either side, boundary zones (23.sub.A, 23.sub.A ') between the central zone (21.sub.A) and respective current supply conductors (30.sub.A, 30.sub.A '). The boundary zones (23.sub.A, 23.sub.A ') having a covering (24.sub.A, 24.sub.A ') of a protective material, comprising a ceramic material having a specific resistance less than 1000 .mu..OMEGA..cm.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.