An optical lens is provided. The optical lens may include a bottom surface, a concave recess provided in a center region of the bottom surface, a first light exit surface having a convexly curved surface on a side opposite to the bottom surface and the recess, and a second light exit surface between the bottom surface and the first light exit surface. A length in a first axis direction on the bottom surface is D1, and a length in a second axis direction perpendicular to the first axis direction is D2, a length in the first axis direction on the bottom of the recess is D3, and a length in the second axis direction on the bottom of the recess is D4, where a length of the bottom surface may have a relationship of D1 D4.