PURPOSE: To reduce a rush current by connecting a phase control circuit at the time of inputting power source and then by connecting a half wave lighting control circuit.

CONSTITUTION: When an ac power source Ac is input, an incandescent lamp 1 is controlled only by a phase control circuit 4, as an initial condition setting circuit A3 is in 'on' condition while an initial condition setting circuit B5 is in 'off' condition. When a circuit 5 is reversed to an 'on' condition, the lamp 1 is controlled by the circuit 4 and a half wave lighting control circuit 6. When the circuit 3 is reversed from an 'on' condition to an 'off' condition, the lamp 1 is controlled only by the circuit 6. A rush current is thus reduced by the circuit 4 by which the current is limited, at the time of inputting the ac power source.