| 摘要 |
PURPOSE:To minimize the defocusing of a picture and to confirm that the defocusing is not caused by the change of the distance between the title device and an object when the defocusing is not caused by the change of the distance by making the quantity of a minute change in an object change confirming operation when a relative ratio is over a reference value smaller than the above-mentioned quantity when the relative ratio is under the reference value. CONSTITUTION:When the change quantity of a focus evaluation value is equal to or over a constant value after the object is focused, the device executes a switching operation so that the minute moving quantity of a lens position can be smaller near the focused position of the object and that the above-mentioned moving quantity can be larger in a position far from the focused position with the relative ratios between plural high frequency components having different bands when the move of the object from the focused point is detected by minutely moving the lens position forward and backward along an optical axis and monitoring the change of the focus evaluation value at this time. Further, a command is transmitted to a focus motor control circuit 27 based on the processed result by a microcomputer 26, a focus motor 4 is driven, a focus lens 2 is moved forward and backward, and an automatic focusing operation is executed. Thus, the confirmation when the distance from the device to the object never changes can be facilitated. |
