Polaroid:
A large sheet of synthetic material packed with tiny crystals of a dichroic substance oriented parallel to one another so that it transmits light only in one direction of the electric vector is called a polaroid.
OR
A thin and large sheet of synthetic material capable of producing plane polarised beams of large cross-section is called polaroid. Example: H-Polaroids, K-Polaroids etc.
Uses of Polaroids:
i. Polaroids are used in motor car head lights to remove head light glare.
ii. Used in three dimensional movie cameras.
iii. They are used to produce and analyse polarised light.
iv. They are used as filter in photography.
v. They are used in window of aeroplanes to control amount of light.
vi. Used in polarising sunglasses (goggles) to protect the eyes from glare of sunlight.
vii. They are used to improve colour contrast in old oil paintings.
viii. They are used in calculators, watches, monitors of laptops which have LCD screens.
