| 摘要 |
PURPOSE:To get ready for next checking operation, by resetting the checking device by closing action of synchronous contact which is necessary and indispensable for emission of flash discharge tube, and making it possible to follow up repeated emission in short intervals. CONSTITUTION:In an automatic dimmer operation electronic flash device of series control type, this is an automatic dimmer operation checking device intended to notify whether an automatic dimmer operation is done or not. In operation, the lighting of LED30 responsible for checking operation is forced to be extinguished by closing a synchronous contact 18, and the both ends of a capacitor 26 in a time constant circuit for controlling the lighting duration of the LED30 are forced to be short-circuited by closing the synchronous contact 18, so that the checking operation is reset. Thus, even in the reset state substantially, due to operation of an amplifier power source 10 to generate an arbitrary voltage simultaneously with emission and of a comparator 17 controlled by this power source, the checking operation can be started by the dimmer signal from a light receiving circuit 9. |
