Patent · US Active

Method for operating a high-intensity discharge lamp, lamp driver and projection system

US7909473B2 · kind B2 · utility

10Cited by
6References
20Claims
0Family size

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Key dates

Filing dateSep 1, 2006
Grant dateMar 22, 2011
Priority date
Expiry dateNov 8, 2027

Classification

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

Abstract

There is described a method for operating a high-intensity discharge lamp (2), in which the high-intensity discharge lamp (2) is acted upon by an AC current (I) which commutates between positive pulses (Ip) and negative pulses (In) with a predefined current amplitude (IA), wherein a pulse width ratio between the pulse width of a positive pulse (Ip) and the pulse width of an adjacent negative pulse (In) is modulated in such a way that the mean current value (I) of two successive positive and negative pulses (Ip, In) fluctuates periodically between positive and negative values. In addition, the value of the current amplitude (IA) is modulated in accordance with a predefined modulation function (M). A description is also given of a corresponding lamp driver (10) for a high-intensity discharge lamp (2) and of a projection system (1) comprising such a lamp driver (10).

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