An input device includes a plurality of detectors for respectively detecting a close approach of an approaching object, and a controller including a plurality of input channels. The plurality of detectors is aligned in a direction. Each of the detectors belongs to one of a plurality of groups each of which two or more detectors belong to. The plurality of detectors in each of the groups is connected in common to one of the input channels associated therewith in the controller. A permutation of the groups which at least three detectors, continuously aligned thus forming a set and arbitrarily selected from the plurality of detectors, respectively belong to is different by each set of at least three detectors.