Principle and Function of Refractometer

Principle and Function of Refractometer

When a beam of visible light passes through the interface between two different substances, the phenomenon of refraction occurs. In an extreme refractive condition (total reflection), the light will not enter the interface of the second substance, but will be reflected as if it encountered a mirror. The incident angle of light when this phenomenon occurs is called the "critical angle".

The size of the critical angle is strictly determined by the refractive index of their two substances. If the refractive index of one substance is known, plus the measurement of the critical angle, then the refractive index of the other substance can be determined. Refractive index is the inherent physical property of each substance. The analysis of liquids is based on the analysis of solute concentration.

Refractometer is an instrument that uses the above principles to measure refractive index, birefringence, and optical properties.

Refractometer function
1. Measuring the refractive index
The refractive index is the physical constant of a substance. Each substance has its own characteristic refractive index. The best gem refractometer can be used to measure medicines, flavors and fragrances, glass, plastics and other items.

2. Measure sugar content
Refractometer can be used to measure Brix value of sugar-rich samples such as juice, syrup, jam, honey, etc The measured value is related to the sugar concentration of the measured sample, and the Brix scale actually indicates the concentration of the sucrose aqueous solution. The conversion value between the Brix value and the refractive index is data using ICUMSA (International Sugar Analysis Method Association).

3. Measure food concentration
Soy sauce and other sauces, seasoning liquids and other liquid foods contain sugar, salt and other substances. The measured value of the refractometer is proportional to the content of soluble solids in these solutions, so that the Brix value can represent the total content of soluble solids in the solution.

4. Measuring the concentration of aqueous solution
Refractometer can be used to determine the concentration of aqueous solutions such as oil-based solutions, pharmaceuticals and heavy chemical products such as motor oil, detergents, glycol, cesium chloride, sodium hydroxide and other substances. There is a proportional relationship between the Brix value and the concentration of each solution. The solution concentration can be determined by the Brix value determined by the refractometer and the established conversion table. The Brix value is the basic scale for determining the soluble solid content in the solution.
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