| 摘要 |
PURPOSE:To attain exact flash emission prevented from misemission by turning on a main thyristor connected to a flash discharge tube in series without fail when a high voltage is applied to the trigger electrode of the flash discharge tube. CONSTITUTION:When a flash start signal A1 is impressed to the 1st input terminal of an OR gate 49 under the state that a capacitor 42 is charged, a thyristor 43 is turned on, the capacitor 42 is discharged and the discharged current is made to flow into the primary coil of a trigger transformer 20A, so that a high voltage is induced in the secondary coil and the discharge tube 8 is turned to the excited state. When the discharge current flows in accordance with ON of the thyristor 43, LC vibration is induced by the inductance of the capacitor 42 and the primary coil of the transformer 20A. Namely, the current flow into the course L3 of capacitor 42 (+) (position Q) diode 47 resitor 48 capacitor 11 gate of main thyristor 9 resistor 10 capacitor 42 (-) (position P). The current is gate ON current for the main thyristor 9, so that the flash discharge tube 9 emits flash. |
