SEMICONDUCTOR LIGHT-EMITTING ELEMENT TURN-ON DEVICE AND LUMINAIRE USING THE SAME

PROBLEM TO BE SOLVED: To take advantage of a transient phenomenon due to intermittent current shunting control near the lower limit of dimming of a semiconductor light-emitting element to superpose a transient voltage or transient current whose level changes in time on the semiconductor light-emitting element, thereby reducing unevenness in or flickering of emission intensity while tolerating a change of color temperatures.SOLUTION: A semiconductor light-emitting element turn-on device comprises a DC power supply which supplies DC current to a semiconductor light-emitting element 2 (converter circuit 1), a series circuit consisting of a shut resistor R1 and a switching element Q2 which are connected in parallel to the DC power supply or the semiconductor light-emitting element 2 (shunt circuit 5), and a reactance element connected in parallel or in series to the shunt resistor R1 (capacitor C2). A transient voltage or transient current occurring in the reactance element when the switching element Q2 is turned on or off is superposed on the semiconductor light-emitting element 2.