A refractometer is a device used to measure the refractive index of a substance. It works by shining a light through the substance, and then measuring the angle of the refracted light. It is commonly used to measure the sugar content of liquids, such as juices, beer, wine, and other beverages, as well as the concentration of aqueous solutions. Refractometers are also used in many industries to measure the viscosity, specific gravity, and other properties of a substance.
