Abbe Refractometers

Refractometers are measuring instruments which put the phenomenon of light refraction (bending) to practical use. They are based on the principle that as the density of a substance increases (such as when sugar is dissolved in water), its refractive index rises proportionately. Refractometers were devised by Dr. Ernst Abbe, a German/Austrian scientist in the early 20th century. The prism in a refractometer has a greater refractive index than the sample solution. Measurements are read at the point where the prism and solution meet. With a low concentration solution, the refractive index of the prism is much greater than that of the sample, causing a large refraction angle and a low reading. The reverse (lower refraction angle and higher reading) would happen with a highly concentrated solution.
Abbe Refractometers are a type of refractometer used for measuring the refractive index of solid samples, such as glass, plastics and polymer films. There are two detection systems for refractive index: transparent systems and reflection systems. Hand-held refractometers and Abbe refractometers use transparent detection systems, and digital refractometers use reflection detection systems. Abbe refractometer readouts can be either digital or analogue. Abbe refractometers are used most often to measure solid samples – something that standard digital refractometers cannot do. Circulating water baths can be added to control instrument and fluid temperature in Abbe refractometers.
Newer versions of Abbe refractometers have recently been upgraded to include solid state Peltier elements to both heat and cool the refractometer so that you no longer need to use a waterbath. Another modern feature is the ability to link the Abbe refractometer to a computer to control the instrument and to record readings. Some Abbe refractometers can measure at wavelengths other than the standard 589 nanometers, using filters on up to the near infrared range. They are referred to as Multi-wavelength Abbe refractometers. Multi-wavelength Abbe refractometers can be used to easily determine a sample's Abbe number, which is a measure of the material's dispersion (variation of refractive index with wavelength) in relation to the refractive index. These multi-wavelength Abbe refractometers can be used to test eyeglass lenses, contact lens materials, optical plastics for optical communication, compact disk materials and insulating oil. Other accessories that are available include digital printers, extra filters and near-IR viewers.

Author Name: Kathy Brasch : Nationalmicroscope.com

Abbe Refractometers

Brix refractometers

You often hear the term brix and brix refractometer when testing samples for sugar content. Just what is a refractometer? A refractometer is an instrument that measures the refraction of light through a substance. The refractive index becomes higher in a substance of higher concentration.

A refractometer has a wide variety of uses such as measuring sugar concentrations and liquid concentrations. Refractometers are sometimes called “Sugar concentration meters” or “Density meters” depending on the application.
Brix and refractive index are common measurement scales for refractometers. A refractometer that measures brix is referred to as a Brix Refractometer. When measuring solutions that have multiple ingredients the Brix value equals the total concentration of dissolved solids.
About the Brix (%) Scale

Brix (%) shows the concentration percentage of the soluble solids content in a sample (water solution). The soluble solids content is the total of all the solids dissolved in the water, including sugar, salts, protein, acids, etc., and the measurement reading is the sum total of these. Basically, Brix (%) is the number of grams of cane sugar contained in 100g of cane sugar solution. When measuring a sugar solution, Brix (%) should perfectly match the actual concentration. With solutions containing other components, especially when one wants to know the exact concentration, a conversion chart is necessary.

Digital versus Analog Brix refractometers

Brix refractometers are available in hand-held (analogue) or digital models. Hand held units are read by putting a drop of sample on the prism, closing the daylight plate and then reading the scale through an eyepiece as the instrument is held up to your eye. A hand-held/analogue unit determines the refractive index or brix by use of the “Transparent System” which measures light as it passes through the sample and the prism. A low concentration sample has a larger angle of refraction so the boundary line falls on the lower part of the scale, whereas a high concentration sample has a small angle of refraction so the boundary line appears in the upper part of the scale.

Digital Brix refractometers use the “Reflected light system. When you put a sample on the prism and press the Start button, the light that is transmitted from under the sample will travel and refract in multiple directions. The angle of reflection is proportional to the refractive index of the sample, and the reflected light is measured by a sensor and converted into the refractive index or brix readout.

Because of their versatility, brix refractometers are used widely to test sugar content in fruit, vegetables, wine and other food products.

Author Name: Kathy Brasch : Nationalmicroscope.com

Brix refractometers

Refractometers

A refractometer is a laboratory or field device for the measurement of an index of refraction.

Refractometers have been thoroughly adopted in agriculture and in food and beverage is a common abbreviation in the United States.

A Refractometer is a precision tool used to measure salinity. Serious hobbyists know that the best way to measure the salinity and specific gravity of aquarium water is to use a refractometer. These precision optical instruments are incredibly accurate even at very low salt levels, and are equally easy to use. Recently, these instruments have become more affordable, so now every aquarium owner can have one to help monitor water conditions.

The Abbe refractometers sold today operate similarly to their predecessors, using the density of a sample to determine its refraction, in physics, deflection of a wave on passing obliquely from one transparent medium into a second medium in which its speed is different, as the passage of a light ray from air into glass. Digital refractometers, the other major bench-top format, reflect light through a prism toward a sample and find the angle at which it refracts and reflects onto the same line.

High performance automatic refractometer offers advanced features associated with the world's best refractometers, such as a secure data storage card, custom programming of concentration scales, highly durable touch screen controls, keyboard lockout security feature, and interfacing with polarimeters.

Author Name: Kathy Brasch : Nationalmicroscope.com

Refractometers

Microscopes

A microscope is an instrument for viewing objects that are too small to be seen by the naked eye. The science of investigating small objects using such an instrument is called microscopy. The term of microscope means to see very small, not visible with the eye unless aided by a microscope.

Microscopes are very essentail for today's life. You may find a variety of microscope models in the market. Microscopes, refractometers and polarimeters are our specialty and we deal in all kinds of microscopes, refractometers and polarimeters from small scale to high-end units. We carry the latest models, and a wide range of microscopes, refractometers and polarimeters, which are available from us at reasonable prices.

Microscopes, Stereo Microscopes, Microscope Cameras and other products such as Refractometers, Brix Refractometers and polarimeters are available at online shop. You will find a variety including clinical microscopes, microscope cameras, VanGuard scopes and brix refractometers. Apart from these models digital microscope cameras are available for clinical and research laboratories.

National Microscope Exchange (NME) is a leader in the field of microscope, refractometer and polarimeter sales and service. We conduct business with all levels of the United States Government, doctors, hospitals, research centers, clinical laboratories, primary and secondary educational institutions, colleges and universities, medical schools, private industry, students, and hobbyists. We provide you with the best possible quotes and services. We guarantee complete satisfaction for your microscope, refractometer and polarimeter purchases and at the best value for your money.

Author Name: Kathy Brasch : Nationalmicroscope.com

Microscopes