Patent attributes
A focus detection apparatus is disclosed which can achieve excellent focus detection performance. The apparatus detects the focusing state of an image-pickup lens based on a phase difference in a plurality of images. The apparatus includes a field lens and a light-receiving element including plural focus detection areas. The light-receiving element includes at least first and second focus detection areas which detect a phase difference in a first direction, and third and fourth focus detection areas which detect a phase difference in a second direction. The intersection position of the first focus detection area and the third focus detection area with respect to the center of the first focus detection area is different from the intersection position of the second focus detection area and the fourth focus detection area with respect to the center of the second focus detection area.
