The principle of refractometer and how to use it
For pure substances, the online refractometer can use the physical property of refractive index to identify and distinguish samples. For binary mixtures (such as a solute dissolved in a solvent) the refractive index can be used to measure the concentration. Quality control can also be performed by monitoring the refractive index for binary or multicomponent mixtures whose composition ratios are known. Due to its rapidity and reliability, the refractive index measurement method has become an advanced measurement method widely used in various industries around the world. It is a very critical link in many standard and laboratory analysis processes.
A refractometer, also known as a refractometer, is an instrument that uses light to test the concentration of a liquid. It is used to measure the refractive index, birefringence, and optical properties. The refractive index is one of the important physical constants of substances. Many pure substances have a certain refractive index. If the substance contains impurities, the refractive index will change, and there will be deviations. The more impurities, the greater the deviation.
The refractometer is mainly composed of high refractive index prism (sapphire), prism mirror, lens, scale (internal scale or external scale) and eyepiece.
Working principle of online refractometer
Refractive index (also known as refractive index, refractive index R.I.) is a physical constant of matter, and pure substances of solid, liquid and gas have a certain refractive index.
For general liquid compounds, when light passes through liquids of different concentrations, different refractive indices will be produced. The higher the concentration, the greater the refractive index. According to the empirical change law of "refractive index of solution - solute concentration" (20°C), it can be used A refractometer easily measures the concentration of a solute.
Refractive index is a specific intrinsic property of matter. and changes with temperature and wavelength. Therefore, through the refractometer, when the temperature and wavelength are known, the concentration of the liquid can be detected by detecting the refractive index. Of course, different substances may have the same refractive index at different concentrations.
Therefore, concentration detection based on refractive index should be performed as far as possible for binary mixtures (liquids composed of only two components). Of course, in practical applications, if the concentration change of a multi-component solution system (there are multiple components in the liquid) is only caused by the change of one of the components, it can be accurately measured by detecting the refractive index. This is also a quantitative measurement. Quality testing can be carried out for mixed liquids with known components. For example, for mixtures like olive oil or orange juice, the measured value is guaranteed to be within a certain range, which can effectively ensure product quality.
