| 摘要 |
PURPOSE: To provide a dimmer device, capable of dimming a discharge lamp and being adaptable to a mercury lamp, etc., and a method thereof. CONSTITUTION: A light receiving sensor part 8 detects brightness (luminous intensity) in a circumference to output a luminous intensity detection signal, and a control circuit 10 receives the luminous intensity detection signal to output a control signal corresponding to the luminous intensity detection signal. An inverter 12 outputs a rectangular wave A.C. having a frequency in response to a given control signal. The series connection body between an inductor L1 , as an impedance means, and a mercury light 21 , is connected to the output circuit side of the inverter 12, and with the higher frequency of the rectangular wave A.C. outputted from the inverter 12, the impedance of each of the inducter Lm, and L2 ... is increased to lessen electric currents, flowing in each of the light 21 and mercury lights 22 ..., to reduce illuminance. With the lower frequency of the rectangular wave A.C. outputted from the inverter 12, the impedance of the respective inducters L1 L2 ,... is lessened to increase electric currents, flowing in the respective lights 21 , 22 ,..., to increase illuminance. |
