| 摘要 |
PURPOSE:To prevent electric power from being wastefully consumed and to improve the durability of an auxiliary light means by providing a range-finder with an operation control means for stoping the flash of auxiliary light if situation where a focusing signal is not obtained for a prescribed period of time or a prescribed number of them are not obtained. CONSTITUTION:When a switch SW1 is turned on, the output of an inverter 2 comes to '1', and a range-finding control circuit 3 starts to operate. A LED 5 is lit up on the instruction of the range-finding control circuit 3. When a focusing signal is obtained after that, a metering control circuit 4 starts to operate to measure the brightness of an object. When a lens is out of focus, a timer T2 is discriminated to see whether or not it has finished measuring a prescribed time. When the timer T2 is discriminated to have finished measuring the prescribed time, a timer T1 is next discriminated to see whether or not it has finished measuring a prescribed time. If the timer T1 has not finished it yet, range-finding is performed without flashing auxiliary light source. When a focusing signal is not obtained even after the timer T1 has finished it, fixed point information is fetched to proceed to a step for obtaining metering information. |
