Integrated circuit devices are disclosed. The integrated circuit device includes a focus detection pixel and a lens. The focus detection pixel includes a photosensitive unit and a photo-insensitive unit in a substrate. The lens is disposed over the focus detection pixel, wherein the photosensitive unit and the photo-insensitive unit are disposed opposite to each other with respect to an optical axis of the lens, and a light beam passing through the lens is simultaneously incident into the photosensitive unit and the photo-insensitive unit.