refraktometrit

Refraktometers are optical instruments used to measure the refractive index of liquids or transparent solids, which indicates how much light is bent when it passes through a material. The measured refractive index is often correlated with concentration, purity, or composition; common applications include determining sugar content in food and beverage industries (reported as Brix), salinity in aquaculture, and concentration of antifreeze or other solutions in laboratories and industry.

Basic refractometers operate by passing light through a sample onto a prism and measuring the critical angle at which total internal reflection occurs. Handheld analog refractometers use a built-in prism and a calibrated scale visible through an eyepiece, while digital refractometers use electronic sensors to convert refractive index into a digital readout. More advanced laboratory instruments, such as Abbe refractometers, provide higher precision and temperature control to account for refractive index dependence on temperature.

Calibration and temperature compensation are essential for accurate results; common calibration substances include distilled water and certified standard liquids. Limitations include sensitivity to impurities, suspended particles, and color, which can distort readings, and the requirement that the sample be transparent to the instrument’s light wavelength. For opaque or highly scattering samples, alternative methods such as density measurement or spectroscopic analysis may be preferable.

Refractometers are valued for their speed, simplicity, and non-destructive measurement, making them widely used across food and beverage production, chemical manufacturing, clinical testing, and research laboratories.