| 摘要 |
PURPOSE:To execute a more stable AF operation without weight of a load to a battery, by inhibiting electrification to a signal projecting means during an electrifying period to an electromagnetic means, as to an active automatic focus controller (AF device) using the signal projecting means such as an infrared light emission diode (IRED), etc. CONSTITUTION:When a switch SW2 is closed by a release operation of a camera, a signal SW2 is generated, an output S12 and S32 of an AND gate 63 and 84 are inverted to an H level, driving transistors 70, 71 are turned on, and electrification to a coil 73 of a driving electromagnetic magnet is started. As a result, by an operation of the AF mechanism, movement of a lens barrel and scanning of IRED are started. On the other hand, the SW2 signal is applied to a frequency dividing circuit, the signal is inverted after a constant interval of time, and supply of a PULL corrent to the coil 73 is stopped. At the same time, an output of an inverting circuit 64 is inverted to an L level, and when a 10M signal is generated, an output of an NAND gate 31 is inverted to an H level, a transistor 34 is turned on and off, and to the IRED40, constant-voltage is applied by synchronizing with a CLOCK signal, and the IRED flickers and emits light by a period of the CLOCK signal. |
