Arrangement for indicating that a selected exposure value is too high, too low or proper

A first voltage divider comprised of a fixed resistor and a light-dependent resistor, and a second voltage divider comprised of two fixed resistors are both connected across the camera battery. A variable attenuator is located in the path of scene light incident upon the light-dependent resistor and...

Ausführliche Beschreibung

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Bibliographische Detailangaben
Hauptverfasser: WAGENSONNER, EDUARD
Format: Patent
Sprache:eng
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Beschreibung
Zusammenfassung:A first voltage divider comprised of a fixed resistor and a light-dependent resistor, and a second voltage divider comprised of two fixed resistors are both connected across the camera battery. A variable attenuator is located in the path of scene light incident upon the light-dependent resistor and is coupled to the diaphragm-setting selector for coordinated movement. Two transistors of complementary conductivity type have their bases connected in common to the first voltage-divider tap and their emitters connected in common to the second voltage-divider tap. Each one of two light-emitting diodes is connected in the collector-emitter circuit of a respective one of the two transistors. An adjustable resistor is connected between the bases and emitters of the transistors for establishing the potential difference across the two voltage-divider taps at which the transistors become conductive and the diodes become illuminated.