| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a focus detection device that enables a focus state of an optical system to be appropriately detected.SOLUTION: A focus detection device comprises: a peak position detection part 21 that drives a focus adjustment lens 32 included in an optical system to calculate an evaluation value on a contrast of an image to be formed by the optical system, and thereby detects a peak position of the evaluation value; a focus detection part 21 that, out of change ratios of the evaluation value to movements of the focus adjustment lens 32, compares a change ratio of the evaluation value on the closest side at the peak position with a change ratio of the evaluation value on an infinity side at the peak position, and thereby determines reliability as an in-focus position at the peak position.</p> |
