| 摘要 |
PURPOSE:To stop flash light emission extremely speedily by connecting a capacitor for stopping light emission in the discharge loop of a flash discharge tube in series and performing flash light emission while said capacitor is charged. CONSTITUTION:When a synchro contact X0 is made, the base potential of a transistor (TR) Q1 which is held at a level H by a resistance R14 falls to a level L, so the TR Q1 turns on. Consequently, the base potential of a TR Q2 goes up to a level H, so the TR Q2 turns on and TRs Q3 and Q4 turn on. Therefore, the collector of the TR Q3 is held at the level H and its H-level signal is applied as a charge control signal A2 to the gate of the 2nd thyristor Q20, which turns on. When the 2nd thyristor Q20 turns on, the remaining charge in the capacitor C4 for stopping light emission is discharged instantaneously through the path of the capacitor C4 for stopping light emission, anode and cathode of the 2nd thyristor Q20, and a line l20 and the thyristor Q20 decreases in current below a hold current and turns off. |
