In one embodiment, an image sensor includes unit pixels, each of the unit pixel including a first sub-pixel and a second sub-pixel adjacent to the first sub-pixel in a plan view of the image sensor; and a lens array including a first sub-lens area on the first sub-pixel of each unit pixel and a second sub-lens area on the second sub-pixel of each unit pixel. The first sub-lens area may include a first micro lens, and the second sub-lens area includes a second micro lens. In addition, the first micro lens may include a depression defined in a central area thereof.