Low wattage metal halide discharge lamp
US4963790A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 27, 1985 |
| Grant date | Oct 16, 1990 |
| Priority date | — |
| Expiry date | Dec 27, 2005 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J61/825
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A low wattage metal halide discharge lamp includes an evacuated envelope wherein is disposed a heat loss reducing member having an arc tube therein and means for interrupting the circuit for the current flow which sustains the electrolytic sodium loss process. In one embodiment, the circuit interruption means includes supporting the arc tube and dome sleeve by a supporting rod that is affixed by a metal strap to the glass stem within the lamp. The primary circuit interrupting effect occurring upon the heat loss reducing member being supported about the arc tube in an electrically insulated manner so as to create a high path of resistance back to the power supply. A substantial reduction of sodium loss along with improved color constancy and voltage stability resulted from interruption of the electrolysis circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.