Which type of lens causes light rays to diverge?

A concave lens is known for its ability to cause light rays to diverge. This type of lens has a surface that curves inward, resembling a bowl. When parallel light rays pass through a concave lens, they are refracted outward, or diverged. The result is that the rays appear to emanate from a focal point located on the same side of the lens as the incoming light.

In contrast, a convex lens converges light rays to a focal point on the opposite side of the lens from where the light enters, while cylindrical and aspherical lenses have specialized designs that serve particular purposes, such as correcting astigmatism or reducing optical aberrations, but do not generally cause divergence of light in the same manner as a concave lens does. Thus, the defining characteristic of a concave lens—and the reason it is the correct answer—lies in its fundamental property of diverging light rays rather than converging them or altering them in a manner specific to cylindrical or aspherical designs.