| 摘要 |
PURPOSE:To shorten the time for deciding a focusing by deriving a light quantity distribution in the longitudinal direction of a line sensor, and utilizing its contrast information. CONSTITUTION:When an output of a line sensor 2c is larger than outputs of line sensors 2a, 2b of both sides, a selector 8 connects a motor 3 to a dividing circuit 7, and an output of a straight line A is obtained. On the contrary, in case when said output becomes small, when it is decided in a comparing circuit 17 that an output of an integration processing circuit 4c is larger than some level, a selector 16 connects a multiplier 15 to the motor 3, a contrast signal by a peak value and a bottom value of the line sensor 2c is divided by an integral value of an output signal of the line sensor 2c in a dividing circuit 14, a code is put to its output, and it is shown as straight lines D1, D2. Also, when it is decided that the output of the integration processing part 4c is smaller than a prescribed level, the selector 16 connects an output of an amplifier 9 to the motor 3, and signals E1, E2 of a prescribed value are obtained. Accordingly, an improvement is executed in an area corresponding to hatching, and a focusing driving operation can be executed quickly and correctly by that portion. |
