A charge coupled device comprises: a semiconductor substrate of one conductivity type; a one-dimensional first charge coupled device including a plurality of continuous electrodes arranged in a one-dimensional array on the semiconductor substrate and a channel region formed below each of the electrodes; a second charge coupled device that is continuous to an end of the first charge coupled device and includes two branched portions, each of the two branched portions comprising at least one electrode arranged in the one-dimensional array; a detecting portion that detects as an electrical signal a charge transferred by each of the branch portions of the second charge coupled device; and a signal output portion that outputs a signal detected by the detecting portion, wherein distal one of the electrodes of the first charge coupled device, which is adjacent to the second charge coupled device, is formed independently from the other ones of the electrodes of the first charge coupled device so as to be fixed at a predetermined dc potential.