HIGH-PRESSURE DISCHARGE LAMP LIGHTING DEVICE AND LIGHTING SYSTEM USING IT

摘要

PURPOSE:To provide a life prolonging effect and allow instantaneous re-lighting by efficiently lighting two light emitting tubes. CONSTITUTION:A high-voltage pulse generating circuit '9 is allowed to generate positive-polarity or negative-polarity high-voltage pulses by a timer circuit 10 for 3min after a power source is turned on to start arc tubes 4S, 4R of a high-pressure discharge lamp 4. A switching control circuit 11 switches the polarity of high-voltage pulses each time the power source is turned on. The arc tubes 4S, 4R are efficiently used. When a failure detecting circuit 13 detects the flame failure of one of the arc tubes 4S, 4R, a pulse regenerating circuit 13 controls the high-voltage pulse generating circuit 9 to regenerate high-voltage pulses. The other arc tube having no flame failure can be instantaneously re- lighted.