Fotografische Kamera mit einer elektronischen Belichtungssteuereinrichtung

摘要

One input of a differential amplifier is connected to a charging or discharging capacitor and the other input to a discharging capacitor that has previously been charged to the voltage across one leg of a voltage divider consisting of a photoconductor and a resistor connected in series across a battery. When the voltages at the two inputs are approximately equal, one branch of the differential amplifier shuts off, de-energizing the shutter control magnet and closing the camera shutter.