| 摘要 |
<p>PURPOSE:To reset a main control SCR and a commutating SCR to off states by providing an AND circuit which inputs each gate-cathode voltage of both SCRS, and a circuit which stops the charging of a main capacitor by the output signal of the AND circuit. CONSTITUTION:When the main capacitor 5 is charged by a boosting circuit 2 composed of a DC-DC converter; the commutating capacitor 14 is charged through resistances 15 and 9 in case a xenon tube 8 off, and a capacitor 13 is also charged. The conduction of the xenon tube 8 flows a trigger current to the main control SCR10 through the capacitor 5, xenon tube 8, commutating capacitor 14, capacitor 13, and resistance 12, so that the xenon tube 8 emits light. A trigger signal is supplied to the commutating SCR16 by a reflection signal from a subject after the xenon tube 8 emits light, and the SCR16 turns on to bias the main control SCR10 reversely by the charge from the commutating capacitor 14; and the light emission of the xenon tube 8 is stopped and the SCR16 is turned off by the charges of the commutating capacitor 14 to realize automatic dimming strobe operation.</p> |
