Acoustic resonance operation of xenon-metal halide lamps
US5121034A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 6, 1990 |
| Grant date | Jun 9, 1992 |
| Priority date | — |
| Expiry date | Sep 6, 2010 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S315/07
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
Miniature high pressure arc lamps containing a substantial pressure of xenon, in addition to metal halide and mercury, can provide instant light at turn-on and are suitable for automotive headlamps. The high pressure of xenon aggravates convection which causes arc bowing and overheating of the envelope above the arc. By operating the lamp at high frequency within selected bands, acoustic modes are excited in the fill which straighten the arc and make the envelope more isothermal. Frequency modulation of the input can be used to broaden the band selected for acoustic operation and relax the tolerance on arc tube and circuit parameters needed for a match. Acoustic operation may also be used to effect physical displacement of the arc for beam switching.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.