| 摘要 |
PURPOSE:To inform a prescribed time before the time when a light can be emitted by detecting the time required for charging extending from some voltage being in the course of charging, to a voltage of a prescribed width above said voltage, and informing it by a buzzer, etc. when the time has reached the time of several seconds before said voltage becomes a photographing available voltage from its value. CONSTITUTION:A flash emitting device emits a light by discharging a discharging capacitor charged from a DC power source. A voltage of the discharging capacitor is applied to a terminal 10, and at the time of a voltage V0, by an output of a comparator 11, an output of a shift register 17 is counted to a voltage V1 by a counter 17, and a value of immediately before an analog switch 12 is turned off is set by data selectors 19, 20. When the voltage becomes V1, a shift output is provided to an address of memories 21, 22 by an output of a comparator 14. A data which has subtracted several seconds before from the time corresponding to the time for reaching the voltage V1 from V0 is written in the memories 21, 22, and at the time of a data corresponding to an input of the selector, buzzer circuit 23 is operated, and the time of a prescribed time before the time when a light can be emitted can be informed. |
