What are the types of convex lenses ? Give their names.

Convex lens are of three types. 

they are 

• biconvex 
• plano convex 
• concavo convex

Convex lenses are thicker at the middle. Rays of light that pass through the lens are brought closer together (they converge). A convex lens is a converging lens. When parallel rays of light pass through a convex lens the refracted rays converge at one point called the principal focus.The two main types of lenses are: Convex Lens (Converging) Concave Lens (Diverging)

Plano-convex Lens: It is curved outwards from one side and the other side plane. It is positive focal length elements that have one spherical surface and one flat surface. These lenses are designed for infinite parallel light use in non-critical applications.