Which type of lens is thinner in the center and thicker at the edges, causing light rays to diverge?

A concave lens is indeed the correct choice because it is designed to be thinner in the center and thicker at the edges, which causes light rays that pass through it to diverge. This divergence of light rays occurs because the curved surfaces of the lens bend the rays outward, making them appear to come from a virtual focal point located on the same side as the incoming light. This property makes concave lenses particularly useful in applications such as glasses for nearsightedness, where the goal is to spread out light rays before they reach the eye.

In contrast, a convex lens is thicker in the center and thinner at the edges, which causes light rays to converge. The plano-concave lens, while it has a similar shape to a concave lens, typically includes one flat surface, affecting how it interacts with light. Aspheric lenses are designed with a more complex curvature to reduce optical aberrations, but they still do not fit the description of being thinner in the center and thicker at the edges.