| 摘要 |
PROBLEM TO BE SOLVED: To provide a focusing device flexibly adaptable to the change of various kinds of object conditions and capable of adequately and accurately making the suppression of hunting and the performance of focusing compatible in the focusing device performing the focusing of a photographing optical system. SOLUTION: This device is provided with a focus detecting means 2 for detecting the focusing information of the photographing optical system 1, a focusing controlling means 3 for driving the system 1 to a focusing condition, based on the focusing information detected by the means 2, and a statistical arithmetic calculation means 4 for performing statistical arithmetic calculation of the focusing information at a plurality of points of time and calculating the variance of the focusing information. The means 3 resumes the driving of the system 1 when the focusing information exceeds a threshold predetermined corresponding to the variance during the drawing of the system 1 is stopped or during the updating of the target driving position for the means 3 is stopped. |
