CONVEX-CONCAVE FRESNEL LENS

A convex-concave Fresnel-lens for a lighting unit of a vehicle is provided. The convex-concave Fresnel-lens includes a convex input surface and a concave output surface. The concave output surface includes a Fresnel structure. The concave output surface has a first radius of curvature, and the convex input surface has a second radius of curvature. The convex input surface is configured to be oriented towards a light source of the lighting unit.