A shift gate is arranged to be adjacent to a pixel column including a plurality of photosensitive pixels. The shift gate controls a storage time of a signal charge generated in the photosensitive pixels based on a shift pulse signal. The signal charge generated in the photosensitive pixels is transferred to an analog shift register via the shift gate. The analog shift register has a plurality of transfer stages independently driven using a plurality of drive signals. The signal charge generated in the photosensitive pixels is successively transferred by the transfer stages, and detected by an output unit provided at an end portion of the analog shift register so that an output signal is converted. The analog shift register makes an addition of the signal charges in accordance with drive signals when the transfer stages transfer the signal charges.