To light again a discharge lamp 4 when detecting that the discharge lamp 4 is exchanged when the discharge lamp 4 is in the service-life termination period.
Since this includes an abnormality lamp detection part 25 to detect a state of the discharge lamp 4, a lamp detection part 24 which is connected to a coupling capacitor C4 of a load circuit 14 and detects lamp installation/non-installation based on a potential of the coupling capacitor C4 at the time oscillation stopping of an inverter circuit 13, and a determination part 23 in which when abnormality of the discharge lamp 4 is detected, an oscillation frequency of the inverter circuit 13 is transitted to a frequency higher than a lighting frequency for a prescribed time, and oscillation of the inverter circuit 13 is continuingly stopped after that when the lamp detection part 24 detects lamp installation after detecting lamp non-installation, and the oscillation stopping state of the inverter circuit 13 is released by determining that another discharge lamp is installed, a lamp exchange reset function RE can be actuated without malfunction even in the case the potential charged in the coupling capacitor C4 is low when the abnormality lamp is detected.
SHIBAHARA SHINICHI
MITSUBISHI ELEC LIGHTING CORP
| JPH11273884A | 1999-10-08 | |||
| JPH01315995A | 1989-12-20 | |||
| JP2002359093A | 2002-12-13 | |||
| JP2001338791A | 2001-12-07 |
Tadahiko Inaba
Kanako Murakami
Nakatsuru Kazutaka
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