ULTRA-HIGH PRESSURE DISCHARGE LAMP LIGHTING METHOD, ULTRA-HIGH PRESSURE DISCHARGE LAMP TO WHICH THE METHOD IS APPLICABLE AND BALLAST FOR USE THEREIN, AND LIGHTING SYSTEM INCORPORATING THE LAMP AND THE BALLAST
US6713972B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 18, 2001 |
| Grant date | Mar 30, 2004 |
| Priority date | — |
| Expiry date | Dec 26, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02B20/00
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
There is provided a novel method of lighting an ultra-high pressure discharge lamp (A1) having a discharge bulb (1) made of quartz glass in which a pair of electrodes (2) and (3) are disposed facing each other, the method including: lighting the lamp with alternating current; and providing a time period of at least one second for which the alternating current assumes a lighting frequency of 5 Hz or lower during a period for which the lamp lights, wherein the electrodes (2) and (3) each have a current withstanding capability against a current 1.5 times or more as high as a current value at which the lamp lights stably. This method enables the ultra-high pressure discharge lamp to have a longer life and exhibit a higher luminance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.