| 摘要 |
PURPOSE:To enable the light emission for a short time by letting a trigger capacitor discharge by way of a switching element right after the light emission of a flash discharge tube. CONSTITUTION:A thyristor 20 being a switching element is provided to a trigger circuit 16, in parallel with a trigger capacitor 17. Gate voltage is applied to the gate of the thyristor 20 right after the start of light emission of a flash discharge tube 13 to conduct the charge of the capacitor 17 is rapidly discharged by way of a thyristor 18, a resistance 19 and a thyristor 20. Hence, sufficiently large reverse bias voltage is applied to a main thyristor 14, which then turns OFF immediately, causing the flash discharge tube 13 to stop emitting light. In this way, even after the triggering of the main thyristor 14, this main thyristor may be turned OFF so that the short-time light emission of the flash discharge tube may be done. |
