Patent · US Active

High-pressure discharge lamp light source device having a power supply device with a switching state for switching from a direct current drive in a standby state to an alternating current drive in an operating state and projector

US8044334B2 · kind B2 · utility

4Cited by
6References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 24, 2009
Grant dateOct 25, 2011
Priority date
Expiry dateJun 1, 2030

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02B20/00
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

To stabilize the arc bright point position of a discharge lamp and suppress deformation of an electrode when an ultrahigh-pressure discharge lamp is operated with extremely low electric power, the lamp is operated by supplying power from a power supply device having a step-down chopper circuit and a full bridge circuit, a rectangular wave alternating current being supplied when it is operated with rated power or dimmed power (about 60 to 80% of rated power), a DC current being supplied during standby power operation of at most 0.5×P (W) with respect to the maximum operating power P (W). Moreover, the high-pressure discharge lamp light source device may be mounted on a projector for projecting images and the mode being changed to standby power operation when there is no change in an image signal, for example, for a prescribed period of time.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.