Introduction to several methods of liquid refractive index

What is the index of refraction? The refractive index is actually the ratio of the speed of light in a vacuum to the speed of light in that medium. The higher the refractive index of the material, the stronger the refraction force formed by the incident light. This article mainly explains in detail the operation methods, working principles and characteristics of five commonly used liquid refractive index methods, including light irradiation method, diffraction grating method, optical fiber Young's interferometry, surface-grazing human-injection method and CCD measurement method. Refractive index is one of the important optical parameters of substances. With the help of refractive index, the optical properties, purity, concentration and dispersion properties of substances can be understood. Other parameters (such as thermo-optic coefficient) are also closely related to refractive index. In chemical industry, medicine In industrial departments such as food, petroleum, and colleges and universities, it is often necessary to measure the refractive index and concentration of some liquids. Therefore, accurate measurement of the refractive index of liquids is of great significance in many research fields.