IMAGE CAPTURE DEVICE AND FOCUS CONTROL METHOD

摘要

Provided are an image capture device and a focus control method capable of performing auto-focus (AF) at high speed by reducing time until a focus control is completed even when a focus control based on a phase difference AF method and a focus control based on a contrast AF method are used in combination. A digital camera performs a correlation operation of two images captured by a pixel pair P1, performs a correlation operation of two images captured by a pixel pair P2, and determines reliability of correlation operation results based on information generated from the two correlation operation results. When the reliability is low, the digital camera performs the contrast AF. Here, the digital camera variably controls a movement step (arbitrary distance) when moving a focus lens in a predetermined range to calculate a contrast value, according to the height of the reliability.

主权项

1. An image capture device that includes an imaging element that images a subject through an imaging optical system including a focus lens, the imaging element including a first signal detection unit that detects a signal based on one beam among a pair of beams that passes through different portions in a pupil region of the imaging optical system, and a second signal detection unit that detects a signal based on the other beam among the pair of beams, and the image capture device comprising:
a focus control unit that performs any one of a first focus control for moving the focus lens to a focusing position determined based on detection signals of the first signal detection unit and the second signal detection unit and a second focus control for moving the focus lens along an optical axis direction by an arbitrary distance in a predetermined movement range and moving the focus lens to a focusing position determined based on contrast of images captured by the imaging element at respective movement positions; a focus control determination unit that determines which one of the first focus control and the second focus control is to be performed based on information generated using the detection signals of the first signal detection unit and the second signal detection unit; and a control unit that variably controls, in the case where it is determined that the second focus control is to be performed, at least the arbitrary distance, among the movement range and the arbitrary distance in the movement range, based on the information.