To enhance AF accuracy by eliminating the effect of miscellaneous objects with high contrast even when they exists at the background of an object.

By a photoelectric conversion element array 2 having a photoelectric conversion element column consisting of plural photoelectric conversion elements, an image signal corresponding to the distribution of the light intensity of an object image is outputted. Then, the image of light from the object is formed on the photoelectric conversion element column by an optical system 1. Based on the output of the array 2, the first arithmetic operation of range- finding is executed by a first arithmetic part 3. Based on the output of the arithmetic part 3, and arithmetic area is set by an arithmetic area set part 4. Besides, the second arithmetic operation of the range-finding is executed in the arithmetic area set by the set part 4 by a second arithmetic part 5. Based on the outputs of the arithmetic parts 3 and 5, a focusing action is executed by a control part 6.