| 摘要 |
<p>PURPOSE:To lower the exciting voltage of a gas tube for control by using an element for stopping light emission provided with 3 poles in said tube. CONSTITUTION:The electric discharge of a capacitor 2 is discharged through a trigger coil 3 by turning on a switch 1 for light emission, and a main electric discharge tube 4 is excited by the high voltage generated in the secondary side of the trigger coil, whereby the electric discharge of a main electric discharge capacitor 5 is started. Following thereto, a photodetector 8 is conducted by reflected light to supply electric charge to an integration circuit 9. When required quantity of light is attained, an SCR10 goes on to conduct the positive pole and negative pole of a gas tube 12 for control to a capacitor 11. When the tube 12 conducts, the charge of the capacitor 5 is discharged and the tube 4 stops discharging. With such constitution, the trigger voltage of the tube is lowered.</p> |
