Imaging apparatus and distance measurement method

An imaging apparatus includes: an imaging unit; a focal range control unit configured to cause the imaging unit to capture a first image and a second image which have mutually different focal ranges, changing a focal position of the imaging unit; a reference image generation unit configured to generate, using the first image and the second image, a reference image to be used as a blur standard; and a distance measurement unit configured to measure a distance to the subject based on a difference in blur degrees between the reference image and each of the first image and the second image. The focal ranges of the first image and the second image are independent of each other, and an out-of-focus space is provided between the focal ranges.