In a range image sensor 8, when a first reverse bias voltage applied between a semiconductor substrate 11 and first semiconductor regions 13 is an H bias, first depleted layers A1 and A1 expanding from the p-n junctions of the first semiconductor regions 13 adjacent to each other expand and link to each other so as to cover a second depleted layer B1 expanding from the p-n junction of a second semiconductor region 14. Accordingly, carriers C generated near the rear surface 11a of the semiconductor substrate 11 are reliably captured by the first depleted layers A1. Further, when a second reverse bias voltage applied between the semiconductor substrate 11 and the second semiconductor regions 14 is an H bias, the second depleted layers adjacent to each other expand and link to each other so as to cover the first depleted layer. Accordingly, carriers generated near the rear surface of the semiconductor substrate are reliably captured by the second depleted layers.