| 摘要 |
PURPOSE:To easily adjust the focus of a lens by automatically moving a photographing lens up to a previously set up prescribed position in the case of setting up a camera to a focusing mode and executing release operation. CONSTITUTION:Since a counter 23 is reset in a normal using state, its output is in an 'L' level, and when a release button is depressed under said state and a switch S4 is turned on, the output of an AND gate 44 is turned to an 'H' level and the output of an AND gate 45 is turned to an 'L' level. When range finding operation based upon a range finding circuit 51 is ended, range finding data obtained by the circuit 51 are inputted to a comparator 59, current supply to a coil 64 is started and the photographing lens starts to move. When the counted value of a counter 58 counting up the ON/OFF frequency of a switch S5 based upon the movement of the photographing lens is equal to the range finding data, the output of the comparator 59 is inverted to the 'H' level, current supply to the coil 64 is stopped and focusing is attained. Consequently, the photographing lens is easily focused within a short time. |
