US Patent No. 9,253,391

IMAGE CAPTURE APPARATUS AND CONTROL METHOD FOR TRACKING OF FOCUS POSITION


Patent No. 9,253,391
Issue Date February 02, 2016 
Title Image Capture Apparatus And Control Method For Tracking Of Focus Position
Inventorship Satoshi Kimoto, Kawasaki (JP)
Assignee CANON KABUSHIKI KAISHA, Tokyo (JP)

Claim of US Patent No. 9,253,391

1. An image capture apparatus comprising:
an image sensor;
a computation unit that computes a focus evaluation value indicating contrast of a subject image included in a focus detection
area using an image signal output from the image sensor;

a first focus adjustment unit that performs focus adjustment through a reciprocating motion of a focus lens;
a second focus adjustment unit that performs focus adjustment by moving the focus lens in a direction toward which the focus
evaluation value increase,

a blur detection unit that detects a blur amount of the subject image; and
a control unit that performs an operation for identifying a direction of a focus position using the first focus adjustment
unit and then performs an operation for identifying the focus position,

wherein in a case that the blur amount is larger than or equal to a first threshold, the control unit performs the operation
for identifying the focus position using the first focus adjustment unit without using the second focus adjustment unit, and

wherein when the blur amount is smaller than the first threshold, the control unit performs the operation for identifying
the focus position using the first focus detection unit and the second focus detection unit.