Different types of lenses Lenses are categorised by the curvature of The 2 optical surfaces. A lens is biconvex (or double convex, or simply convex) if both surfaces are convex. If the two surfaces contain the identical radius of curvature, the lens is equiconvex. A lens with two concave surfaces https://napkinpodge16048.fitnell.com/64239878/top-latest-five-qoo10-배송-urban-news