The solid or liquid sample of a refractive index can be measured using a refractometer. Research scientists in the food and beverage industries and jewelry gemologists utilize refractive index meters. Well, what is a Refractometer is the most important question. The use of a refractometer can also be beneficial to those who enjoy home-brewing or maintaining saltwater aquariums. When light moves into a sample from the air, it is bent (or refracted) in a refractometer. Therefore, a refractive index measurement is typically carried out by a refractive index meter.
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Types of Refractometers
Refractometers come in three main types. Mobile handheld measurement systems are one type. Typically, bench or Lab refractometers are used in laboratories or industrial settings. An Abbe refractometer is an optical-mechanical instrument named after its inventor. Finally, a digital automatic refractometer includes modern software in its measurement process.
Light is measured by its refraction index, which measures how fast it moves through materials. Using the speed of light in a vacuum and the speed of light in a substance, the refractive index (n) is calculated. As a result, we have a value between 1.3000 and 1.7000 that is unitless. Reports are usually given to the ten-thousandth place.
When it comes to measuring liquid samples, refractometers are most commonly used. In addition to identifying a liquid sample, assessing its purity, and determining its solute concentration (dissolved materials), researchers may use the refractive index to accomplish several other tasks. For example, refractometers may also use the Brix scale to measure sucrose concentrations in water at a certain temperature and relate those values to refractive indexes.
Uses of Refractometer
The food and beverage industry uses refractive index meters for quality control purposes. Identifying gemstones with refractive indexes is another use for refractive indexes. Additionally, homebrewers can use refractometers to measure the specific gravity of their beer, as well as aquarists to measure water salinity and specific gravity.
How a Refractometer Works
A liquid changes the direction of light when it enters; this is known as refraction. The angle of refraction, which is measured by a refractor, indicates how much light is refracting. Refractors measure refraction angles and correlate them to refractive index values (nD). These values are used to measure the concentration of a solution. Solution concentration in water determines the refractive index of the solution.
Prism in a refractometer
Prisms in refractometers have greater refractive indices than solutions. Therefore, we read the measurements when the prism meets the solution. Due to the greater refractive index of the prism in low concentration solution, a large refraction angle and low reading result (“A” on diagram). If the solution were high in concentration, results would be reversed (“B” on the diagram).