A flicker detection system according to the present invention has an AC component extracting circuit that extracts an AC signal from a voltage applied to a lamp, the AC signal being an AC component of the voltage applied to the lamp, a display section adapted for displaying the information that flicker has occurred, and a control section that has a reference voltage registered in advance for determining that flicker has occurred and instructs the display section to display the information that flicker has occurred in the lamp, depending on the result of comparison between the reference voltage and the AC signal received from the AC component extracting circuit. In the present invention, when flicker occurs in a lamp, the voltage fluctuation generated between the lamp electrodes exceeds the reference voltage, and accordingly, the occurrence of flicker is determined by comparing the AC signal representative of the voltage fluctuation with the reference voltage, and when flicker occurs, a display to that effect is made.