The anode sides of respective EL elements E1-E4 constituting icons are connected to a first potential V1, the cathode sides of the EL elements E1-E4 are connected to current absorption sides of constant current sources I1-I4, and current output sides of the constant current sources are connected to a second potential V2 whose potential is lower than that of the first potential via light emission control switches S11-S14. Current regulating resistors R101-R104 are connected in parallel corresponding to the respective EL elements E1-E4, and therefore by appropriately selecting the resistance values of the current regulating resistors R101-R104, light emission intensities of the respective EL elements E1-E4 constituting icons can be regulated appropriately. During an all extinction period during which the respective EL elements E1-E4 are all extinguished, an analog switch S201 is turned off, and an analog switch S202 is turned on. Thus, the anode sides of all EL elements E1-E4 become ground potential, and a reverse bias voltage is applied to all EL elements E1-E4. By periodic applying of this reverse bias voltage, the light emission lifetimes of the EL elements E1-E4 can be prolonged.