Camera with automatic focus and illumination controls - uses opto-electronic light meter with photodiodes to regulate electromagnets in response to range finder and brightness signals

摘要

The camera illumination and focus adjustment system embodies three main sections, the light metering circuit (A), the automatic illumination control (B) and the automatic focussing control (C). The movements of the mechanical components are initiated by electro-magnets (Mg1, Mg2, Mg3) each connected to a transistor (Tr1, Tr2, Tr3). The electronic circuit connections enable sequential or simultaneous movement of the automatic manipulators to be followed, dependent on the readings from the light meter. A prismatic triangular method is used for the distance measurement. The light meter (A) embodies a number of stages (typically 8) each with a control resistor (VR), diode (D), photo-diode (PD) and operational amplifier(IC). In the electronic circuit, the signals from the distance measuring prism, converted into electrical signals are added by a summator and passed through a comparator to an amplifier connected by a capacitor to another amplifier.