A solid-state imaging device comprising: a plurality of photoelectric converting portions, each having a photosensitive region configured to generate a charge according to incidence of light and which has a planar shape of a rectangular shape composed of two long sides and two short sides, and a potential gradient forming region configured to form a potential gradient in the photosensitive region increasing along a first direction parallel to the long sides forming the planar shape of the photosensitive region and directed from one short side to the other short side forming the planar shape of the photosensitive region, the plurality of photoelectric converting portions being juxtaposed along a direction intersecting with the first direction; and first and second shift registers (9, 13) configured to acquire charges transferred from the respective photoelectric converting portions and configured to transfer the charges in the direction intersecting with the first direction to output the charges, and are arranged on the side of the other short side forming the planar shape of the photosensitive region; a plurality of first transfer portions, each being arranged corresponding to a respective photoelectric converting portion and between each said photoelectric converting portion and the first shift register, and each configured to transfer a charge from the photosensitive region of the corresponding photoelectric converting portion to the first shift register; a plurality of second transfer portions, each being arranged corresponding to a respective photoelectric converting portion and between each said first shift register and the second shift register, and each configured to transfer a charge transferred to the first shift register to the second shift register; a plurality of buffer gate portions each being arranged corresponding to a respective photoelectric converting portion on the side of the other short side forming the planar shape of the photosensitive region and being interposed between said photoelectric converting portion and the first transfer portion, and each configured to accumulate a charge from the corresponding photoelectric converting portion, an amplifier portion configured to convert the charges output from the first and second shift registers (9, 13) into voltages, and to output the voltages of the respective photoelectric converting portions juxtaposed in the direction intersecting with the first direction; characterized in that the potential gradient forming region comprises a pair of electrodes (51, 52) made of an optically transparent material and a control circuit configured to supply a signal MGL to one end of one electrode and a signal MGH to the other end of the electrode and to the other electrode so as to provide said potential gradient. a plurality of photoelectric converting portions, each having a photosensitive region configured to generate a charge according to incidence of light and which has a planar shape of a rectangular shape composed of two long sides and two short sides, and a potential gradient forming region configured to form a potential gradient in the photosensitive region increasing along a first direction parallel to the long sides forming the planar shape of the photosensitive region and directed from one short side to the other short side forming the planar shape of the photosensitive region, the plurality of photoelectric converting portions being juxtaposed along a direction intersecting with the first direction; and first and second shift registers (9, 13) configured to acquire charges transferred from the respective photoelectric converting portions and configured to transfer the charges in the direction intersecting with the first direction to output the charges, and are arranged on the side of the other short side forming the planar shape of the photosensitive region; a plurality of first transfer portions, each being arranged corresponding to a respective photoelectric converting portion and between each said photoelectric converting portion and the first shift register, and each configured to transfer a charge from the photosensitive region of the corresponding photoelectric converting portion to the first shift register; a plurality of second transfer portions, each being arranged corresponding to a respective photoelectric converting portion and between each said first shift register and the second shift register, and each configured to transfer a charge transferred to the first shift register to the second shift register; a plurality of buffer gate portions each being arranged corresponding to a respective photoelectric converting portion on the side of the other short side forming the planar shape of the photosensitive region and being interposed between said photoelectric converting portion and the first transfer portion, and each configured to accumulate a charge from the corresponding photoelectric converting portion, an amplifier portion configured to convert the charges output from the first and second shift registers (9, 13) into voltages, and to output the voltages of the respective photoelectric converting portions juxtaposed in the direction intersecting with the first direction; characterized in that the potential gradient forming region comprises a pair of electrodes (51, 52) made of an optically transparent material and a control circuit configured to supply a signal MGL to one end of one electrode and a signal MGH to the other end of the electrode and to the other electrode so as to provide said potential gradient.