An imaging device is provided that includes a first imaging element, a second imaging element, and a focal point detector. The first imaging element includes a first opto-electrical converter configured to convert light into an electrical signal. The second imaging element is configured and arranged to receive light incident on and passing through the first opto-electrical converter. The second imaging element includes a second opto-electrical converter configured to convert the light coming from the first opto-electrical converter into an electrical signal. The focal point detector is configured to perform focal point detection based on first image data obtained by the first imaging element and second image data obtained by the second imaging element.