Focus detection device and image capturing apparatus provided with the same

摘要

The focus detection accuracy of a focus detection device that employs an external AF sensor unit having a pair of line sensors that are each comprised of multiple unit line sensors is improved. The individual line sensors are arranged so that the center of the field of view of an imaging optical system at a predetermined subject distance, at which field-of-view adjustment for causing the field of view of the imaging optical system and the field of view of a focus-detection optical system to match has been carried out, corresponds to the center of one of the multiple unit line sensors included in the individual line sensors.

主权项

1. A focus detection device including a focus-detection optical system having optical axes that are separate from an optical axis of an imaging optical system, the device comprising:
a plurality of pairs of line sensors including a first pair of line sensors and a second pair of line sensors, each line sensor having multiple pixels, wherein the first pair of line sensors and the second pair of line sensors are arranged in parallel, and wherein the first pair of line sensors and the second pair of line sensors corresponds to a same focus detection area; and a detection unit that detects the distance of a subject on which focus detection is to be carried out based on a phase difference between the signals of the subject images obtained by the photoelectric conversion performed by the first pair of line sensors and the second pair of line sensors, wherein: the first pair of line sensors and the second pair of line sensors are adjacently arranged in the direction orthogonal to the alignment direction of the multiple pixels so that a field of view of each line sensor of the first pair of line sensors includes the center of the field of view of the imaging optical system and that a field of view of each line sensor of the second pair of line sensors does not include the center of the field of view of the imaging optical system, the first pair of line sensors are arranged at the top of the plurality pairs of line sensors in the direction orthogonal to the alignment direction of the multiple pixels, and wherein the first pair of line sensors and the second pair of line sensors are arranged so that, regardless of change of focus length occurring within the imaging optical system, a field of view of each line sensor of the first pair of line sensors includes the center of the field of view of the imaging optical system and a field of view of each line sensor of the second pair of line sensors does not include the center of the field of view of the imaging optical system.