Question

What is a lens? State its type and explain briefly.​

Answer 1

What are Lenses?

A lens is a transmissive optical device that focuses or disperses light beams by means of refraction.

Types Of Lenses

The classification of a lens depends on how the light rays bend when they pass through the lens. The two main types of lenses are:

• Convex Lens (Converging)
• Convex Lens (Converging)Concave Lens (Diverging)

Convex Lens - Convex lenses are thick in the middle and thinner at the edges.

Concave mirror - A concave lens is flat in the middle and thicker at the edges.

Other Lens Types are:

• Cylindrical – curvature in one direction
• Fresnel – narrow ring-like surface
• Lenticular – a group of micro-lenses
• Gradient Index – flat surfaces but with varying refractive indices
• Axicon – conical surface

Applications Of Lens

They all use convex lenses. And have any of you wondered why people look so weird when you see them through a peephole? That’s because the glass used there isn’t a normal one. It is a concave lens. Convex lenses are used to correct farsighted vision problems.