To more accurately focus based on the output of range finding in every prescribed range finding block, if a difference between maximum and minimum outputted values of the range finding values is below the prescribed value, even in the case of judging that all the outputs of the range finding value is not reliable.

Data of range finding information obtained by a range finding part 2 are formed by a range finding information calculation part 7, and the reliability of the data is decided by a reliability deciding part 9, thereafter, it is transferred as the range finding value to a photographic lens control part 8. The driving quantity is calculated based on the transferred value, then, the focusing drive of the photographic lens 10 is executed. In this case, the difference between the maximum and minimum values of the range finding values is calculated from the prescribed range finding block. In the case the difference is below the prescribed value and also a photographic depth or the contrast is below the prescribed value, the closest range finding value is set. That is, even in the case of deciding that the reliability does not exist, when the range finding value within the prescribed extent is presented by all the prescribed range finding blocks, the presented value is adopted as the range finding value and outputted.