Patent ID: 8773560

Claim:
A method for driving an image pickup apparatus that includes a plurality of photoelectric conversion units, each including a plurality of photoelectric conversion elements, a plurality of amplification units, each of which is shared by the plurality of photoelectric conversion elements included in each of the plurality of photoelectric conversion units and amplifies signals of the plurality of photoelectric conversion elements, and a plurality of common output lines that output signals obtained from the plurality of amplification units, the method comprising: generating a signal for focus detection by a first operation, in which a signal of at least one of the plurality of photoelectric conversion elements included in each of the plurality of photoelectric conversion units is read to an input node of a corresponding one of the plurality of amplification units and the signal is then supplied to a corresponding one of the plurality of common output lines by the amplification unit; and generating a signal for forming an image by a second operation, in which at least a signal of a photoelectric conversion element from which the signal has not been read in the first operation and that is included in the same photoelectric conversion unit as that including the at least one photoelectric conversion element from which the signal has been read in the first operation is read to the input node of the amplification unit and added with the signal read in the first operation while holding the signal read in the first operation using the amplification unit and the added signals are supplied to the common output line by the amplification unit.