LENS SYSTEM, IMAGING DEVICE, AND IMAGING SYSTEM

A lens system that forms an image on an imaging element, includes: first to third lens element arranged in order; a diaphragm; and a lens element on the image surface side. At least one of the first and second lens elements has a free-curved surface, and one of the first and second lens elements has free-curved surfaces on both sides. The third lens element has free-curved surfaces on both sides. The first lens element has a convex shape, toward the object side, of a surface facing the object side. The second lens element has a convex shape, toward the object side, of a surface facing the image surface side. The third lens element has a convex shape, toward the image surface side, of a surface facing the object side. The lens element on the image surface side has, at least on the object side, a free-curved surface.