Refractometer
A refractometer is a laboratory or field device for the measurement of an index of refraction (refractometry). The index of refraction is calculated from Snell's law while for mixtures, the index of refraction can be calculated from the composition of the material using several mixing rules such as the Gladstone–Dale relation and Lorentz–Lorenz equation. Types of refractometers There are four main types of refractometers: traditional handheld refractometers, digital handheld refractometers, laboratory or Abbe refractometers, and inline process refractometers. There is also the Rayleigh Refractometer used (typically) for measuring the refractive indices of gases. In veterinary medicine, a refractometer is used to measure the total plasma protein in a blood samples. In drug diagnostics, a refractometer is used to measure the specific gravity of human urine. In gemology/gemmology, the gemstone refractometer is one the fundamental pieces of equipment used in a gemologica...