Uses of Polaroid :
1. To remove glare : Polaroid is used to reduce the glare caused by reflection of light from extremely white or bright surfaces or wet roads or the scorching sun. Glare consists of partially polarized light. If polaroid glasses are worn on the eyes, it will cut off the horizontal vibrations of partially polarized light. Hence the glare will be eliminated.
2. To prevent accidents : When the light emitted from the headlights of motor cars and trucks falls on the hood of a motor car or truck coming from the other side, the reflected light reaches the eyes and causes glare. This not only causes pain to the eyes, but there is also a possibility of an accident. To overcome this, headlight cover glass and windscreen are made of polaroid.
3. In polaroid camera or photography : A polaroid is placed in front of the lens of the polaroid camera so that the polarized light coming in its background is blocked by the polaroid.
4. To determine the concentration of sugar: The concentration of sugar is determined by polari meter. Polaroids are used to produce and analyze plane polarized light in a polari meter.
5. In the study of optical properties of metals.
6. To study the effect of stresses.