摘要 |
An electronic shutter control circuit in a camera has an operational amplifier, a light receiving element connected between the input terminals of the operational amplifier and a logarithmic compression diode, one terminal of which is connected to the cathode of the light receiving element. The circuit further comprises an integrating capacitor, one terminal being connected to the cathode of the light receiving element and the other terminal together with the remaining terminal of said logarithmic compression diode being connected through respective resistors to the anode of the light receiving element. A timing switch is operated in synchronization with the running of a shutter top curtain, and the output terminal of the operational amplifier is connected from a terminal of said logarithmic compression diode to the other terminal of the integrating capacitor by the operation of said timing switch.
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