A light-emitting unit is provided in a light-emitting branch path section that branches off between an inductor and a capacitor in a resonant circuit section. The light-emitting unit includes a light-emitting diode that generates illumination light by emitting light, a discharge switching element that is provided in the light-emitting branch path section and switches on and off discharge from the capacitor by switching, a charge switching element that is provided on the inductor side of a branch point of the light-emitting branch path section in the resonant circuit section and switches on and off charging to the capacitor, and a drive circuit section that controls the discharge switching element and the charge switching element by individual on/off driving. The drive circuit section controls the ON period of the charge switching element prior to the ON timing of the discharge switching element.