There is provided an improved light source including a plurality of light emitting elements in a surface. An arrangement of the plurality of light emitting elements fulfills, in an assumed projection area, an element interval at which irradiation light beams of the plurality of light emitting elements overlaps, and fulfills an element interval at which a speckle pattern of each of the irradiation light beams obtained in the assumed projection area is different for each of the irradiation light beams.