Ans. CONVEX LENS
The tens which causes incident parallel rays to converge at a point is known as convex lens or converging lens.
This lens is thicker at the centre and thinner at the edges.
Types of Convex Lenses
There are three types of a convex lens: Double convex lens Plano-convex lens Concavo-convex lens
The lens which causes the incident parallel rays of light to diverge from a point is called concave lens or diverging lens.
This lens is thinner at the centre and thicker at the edges.
Types of Concave Lens
There are three types of concave lens:
(i) Double concave lens
(ii) Plano-concave lens