A plano-convex lens is compose of a plane and convex surfaces, has a positive focal length.It is used for the changing between point light source and parallel beam.It is mean when the light through ...

Lens is a transparent glass which is bounded by two spherical surfaces. The light rays are refracted after passing through the lens. It is of two types, convex lens and concave lens.

The case itself is made out of polymers which, depending on the voltage change the lens' to be more convex or concave, allowing it to "zoom in or out," like changing the focal length on a camera.

Convex and concave lenses can both be used to correct defects of vision. The most commonly occurring defects of vision are ‘short sightedness’ and ‘long sightedness’. People who are ...

When the polymer becomes more convex the lens effectively zooms in. Scientists hope one day this could help create a prosthetic eye or a camera that can be controlled using eyes alone.

The properties of concave and convex lenses were first described around the year 1000, although magnifiers in the form of lens-shaped crystals or glass may have been used much earlier.