A polarimeter is a scientific instrument used to measure the angle of rotation caused by passing polarized light through an optically active substance
Some chemical substances are optically active, and polarized (uni-directional) light will rotate either to the left (counter-clockwise) or right (clockwise) when passed through these substances.
The amount by which the light is rotated is known as the angle of rotation. The angle of rotation is basically known as observed angle. Many chemical substance changes their properties when polarized light is passed through it. Polarimeter is used widely and extensively in the Food & Beverage industries.
Pharmaceutical as well as chemical industries finds innumerable applications of Polarimeter.