A blinking-signal device 1 includes a light receiving section 10, a row selecting section 20, a readout section 30, a detecting section 40, and a control section 50. By the row selecting section 20, charge generated in its photodiode of each pixel unit P2i-1,n of the (2i−1)-th row in the light receiving section 10 is accumulated in its charge accumulating section during a first period, and charge generated in its photodiode of each pixel unit P2i,n of the 2i-th row in the light receiving section 10 is accumulated in its charge accumulating section during a second period. With the detecting section 40, it is detected whether or not light reaching the pixel units P2i-1,n and P2i,n is a blinking signal on the basis of a difference between data D2i-1,n and D2i,n of the pixel units P2i-1,n and P2i output from the readout section 30.