An image sensor includes different first and second focus pixels in a substrate; a first adjacent pixel in the substrate and adjacent to the first focus pixel in a positive first direction, a pixel being absent between the first focus pixel and the first adjacent pixel; a first micro-lens covering the first adjacent pixel; a second adjacent pixel in the substrate and adjacent to the second focus pixel in a positive first direction, a pixel being absent between the second focus pixel and the second adjacent pixel; and a second micro-lens covering the second adjacent pixel, and an area of the first micro-lens being different from an area of the second micro-lens.