DISCHARGE LAMP LIGHTING DEVICE AND PROJECTOR - MATSUSHITA ELECTRIC WORKS LTD

Title:

DISCHARGE LAMP LIGHTING DEVICE AND PROJECTOR

Document Type and Number:

WIPO Patent Application WO/2005/122652

Kind Code:

A1

Abstract:

A discharge lamp lighting device comprising a DC power supply part (3) for rectifying and smoothing an AC voltage; a current detecting circuit (5) for detecting a current flowing through a discharge lamp (La); a power supply ripple detecting circuit (9) for detecting a variation of the voltage supplied from the DC power supply part and outputting a voltage obtained by superimposing the detected voltage on an output voltage of the current detecting circuit; and a control circuit (8) for controlling, based on the output voltage from the power supply ripple detecting circuit, the output voltage to be applied to the discharge lamp in such a manner that the current flowing through the discharge lamp becomes a constant current. The superimposing rates of the output voltage of the power supply ripple detecting circuit (9) may be switched in accordance with the discharge lamp voltage or power.

Inventors:

HASEGAWA JUNICHI (JP)
KONISHI HIROFUMI (JP)
KISHIMOTO AKIHIRO (JP)
WATANABE KOJI (JP)
NAKADA KATSUYOSHI (JP)

Application Number:

PCT/JP2005/005141

Publication Date:

December 22, 2005

Filing Date:

March 22, 2005

Export Citation:

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Assignee:

MATSUSHITA ELECTRIC WORKS LTD (JP)
HASEGAWA JUNICHI (JP)
KONISHI HIROFUMI (JP)
KISHIMOTO AKIHIRO (JP)
WATANABE KOJI (JP)
NAKADA KATSUYOSHI (JP)

International Classes:

H05B41/24; H05B41/282; H05B41/288; (IPC1-7): H05B41/24; H05B41/282

Foreign References:

JP2003031394A	2003-01-31
JPH0521175A	1993-01-29

Other References: