| 摘要 |
A focus detection apparatus which includes an image pickup element having first and second photoelectric conversion elements sharing a lens, wherein the first and second photoelectric conversion elements 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 includes an image shift amount calculator which performs a correlation calculation by using each of signal values obtained independently from the first and second photoelectric conversion elements and calculate an image shift amount, a defocus amount calculator which calculates a defocus amount by multiplying the image shift amount by a coefficient, and a coefficient correcting portion which corrects the coefficient in accordance with the signal value obtained from the first photoelectric conversion element or the second photoelectric conversion element. |
