Question

to polarise the light polariser are used ,what are that polariser?

Answer 1

Hey
These are optical filter that lets light waves of a specific polarization pass and block light waves of other polarsition.

Answer 2

A polarizer or polariser is an optical filter that lets light waves of a specific polarization pass and blocks lightwaves of other polarizations. It can convert a beam of light of undefined or mixed polarization into a beam of well-defined polarization, that is polarized light.