Auto focus control is exerted based on a focus evaluation value indicating a degree of sharpness of an image obtained from a plurality of image pickup devices placed at positions of different light path lengths. There is provided a device which makes a correction on sensitivity of the focus evaluation value obtained from each image pickup devices. It is thereby possible to make an adequate correction on a sensitivity of the focus evaluation value so as to exert the auto focus control with high accuracy. It is also possible to automatically make a correction on the sensitivity of the focus evaluation value and eliminate troublesome labor. All or a part of signal processing for the auto focus control is performed by a single processing part by time-sharing. Thereby, a circuit scale can be miniaturized and power consumption can be reduced.