| 摘要 |
An electronically controlled shutter for a through-the-lens camera which is designed for use with interchangeable lenses of differing maximum aperture. The shutter includes an integrating circuit having a light sensitive device and a capacitor, connected to the base of a transistor, which is gated on for a reference time interval proportional to the intensity of received light. To compensate for lenses having a different maximum aperture, the circuit includes a resistor having a sliding tap, connected to the emitter of the transistor, and which is physically moved by a pin on the interchangeable lens. Thus, the bias on the transistor is altered to compensate for the different exposure calculation required by each lens.
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