Patent ID: 9215364
Filing Date: 2015-12-15
Classification: H04N

Abstract:
1. A focus detection apparatus which includes an image pickup element having a first photoelectric conversion element and a second photoelectric conversion element which share a lens, wherein the first photoelectric conversion element and the second photoelectric conversion element perform a photoelectric conversion of images passing through different exit pupils of an image pickup optical system so as to output a focus detection signal used for focusing by a phase difference detection method, the focus detection apparatus comprising: a processor performing a correlation calculation by using each of signal values obtained from the first photoelectric conversion element and the second photoelectric conversion element respectively, and calculating an image shift amount; the processor performing a calculation of a defocus amount by multiplying the image shift amount by a coefficient; the processor performing correction of the coefficient in accordance with the signal value obtained from at least one of the first photoelectric conversion element and the second photoelectric conversion element; and the processor determining a maximum value of the plurality of signal values obtained from at least one of the plurality of first photoelectric conversion elements and the plurality of second photoelectric conversion elements in a focus detection area, wherein the processor corrects, when the signal value obtained from at least one of the first photoelectric conversion element and the second photoelectric conversion element is greater than a predetermined value, the coefficient so that the coefficient increases, compared with a case where the signal value is less than or equal to the predetermined value, and wherein the processor corrects the coefficient so that the coefficient increases as the maximum value is increased.