Question

What is the meaning of lens​

Answer 1

Lens are the sperical surface which are used as peeping hole and curing the defects of eye . 2 types of lens are : -

Concave lens

Convex lens

Hope it's helpful

Answer 2

$\huge\mathcal\color{teal} Answer :-$

A lens is a transmissive optical device that affects the focus of a light beam through refraction.

A simple lens consists of a single piece of material, while a compound lens consists of several simple lenses (elements), usually along a common axis. Lenses are made from transparent materials such as glass, ground and polished to a desired shape.

A lens can focus light to form an image, unlike a prism, which refracts light without focusing. Devices that similarly refract radiation other than visible light are also called lenses, such as microwave lenses or acoustic lenses.

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There are two types of lenses :- Concave and convex

Concave lens :- Thin in the middle but thicker at the edges.

Convex lens :- Thick at the centre but thinner at the edges.

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Hope it helps !