| 摘要 |
PROBLEM TO BE SOLVED: To eliminate simultaneous turn-on of an electronic luminescence(EL) element at the time of stroboscopic light emission and to prevent the voltage of a main capacitor from being lowered by separating an energy supply path to the EL element from a light emission loop and making the trigger system of an electric discharge tube and the switching system of the EL element different. SOLUTION: When the level of an SCHG signal outputted from a CPU 1 is set to be low, a boosting power source circuit 3 is actuated and the main capacitor C5 is charged by the boosted voltage. Then, the voltage is also generated at the anode of a diode D4. When the voltage arrives at the prescribed charging voltage, the action of the boosting circuit 3 is stopped. Continuously, when the level of the SCHG signal is set to be low again, the boosting circuit 3 is actuated and the voltage is generated. When the level of an IGBTON signal is set to be high at the same time that the level of the SCHG signal is set to be low, the voltage is impressed on the EL element 8. When an IGBT is turned off, electric charge stored in the element 8 is discharged through a resistance R13. In such a case, energy for turning on the element 8 is supplied from the boosting circuit 3. |
