DISCHARGE LAMP LIGHTING UNIT AND ILLUMINATION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a discharge lamp lighting unit and an illumination system capable of suppressing power consumption at a reset operation for an accumulated lighting time caused by the turn-on/off of a power source switch. SOLUTION: The discharge lamp lighting unit is provided with a lighting part 2 supplying power for lighting a discharge lamp La and a control circuit 30 controlling the lighting part 2 so that the supplied power to the discharge lamp La is gradually increased by compensating for the deterioration of luminous flux caused by an increase in an accumulated lighting time for the discharge lamp La. When power to the lighting part 2 is turned on/off according to a prescribed procedure, the accumulated lighting time is reset by the control circuit 30. A high-speed clock generating circuit 7a becoming a source for clock supply during the lighting of the discharge lamp La and a low speed clock generating circuit 7b becoming a source for clock supply in the control circuit 30 during the switching-off of the discharge lamp La with a lower frequency than the clock in the high-speed clock generating circuit 7a are provided as sources for clock supply to the control circuit 30. Consumed power is reduced by the use of the low speed clock generating circuit 7b. COPYRIGHT: (C)2009,JPO&INPIT