Understanding RefractometersRefractometers are precise optical instruments that determine the purity of liquids, gels and solids by measuring their refractive index (RI). The refractive index is the speed of light in the substance as compared with the speed of light in a vacuum. Refractive index measurements are unique, constant, physical characteristics specific to substances.
Refractometers provide RI and % Brix measurements (and other standard scales) for a broad range of industries including agricultural, flavors, fragrance, chemical, petrochemical, industrial fluids, pharmaceutical, automotive, and aviation. A common use is in the food and beverage industry to calculate the concentration of dissolved solids in solution or the % Brix.
Reichert refractometers are built with the highest level of attention and precision to accurately measure the Refractive Index and concentration of liquids, gels and solids. They are accurate, reliable, and durable, offering outstanding value and optimum performance. From traditional transmission units like the Abbe Mark III, to the automatic digital r2i300, to the top of the line AR9, Reichert has the right instrument solution.
Which Refractometer is Right for Your Lab?With this overview, Reichert makes it easy to determine which refractometer suits your needs. Determine the specific requirements of your applications within your industry and within your budget and then select the appropriate instrument.
Refractometer Buyer’s Guide
Selecting the Right Refractometer
Identify answers to the following 6 questions, and then simply pick the appropriate Reichert refractometer from the chart on the back.
1 Measurement Range and Accuracy
What level of accuracy is required? The first step in matching the appropriate instrument is to know the range and accuracy demands of the application. The range is in terms of either Refractive Index or % Brix based on the types of samples to measure. The accuracy requirement is established by the specifications for your product and the criticality of the concentration measurement. In other words, what is the highest and lowest reading value you expect to encounter? And what is the level of accuracy?
2 Temperature Range and Control Is control of the temperature of the sample critical for the application? Refractive Index varies with temperature so it is important to consider the temperature control range of a refractometer. Some samples require measurements at elevated temperatures to match production conditions. But if temperature requirements are less stringent, a lower cost model may be appropriate.
3 Sample TypeWhat type of sample is being measured? Is the sample a liquid? If so, is the liquid sample transparent, translucent, or opaque? Is the sample a solid? Select the sample gradient that best matches your sample:
Sample Type Gradient Model
Gradient I - Transparent: water, solvents, alcohol, beveragesReicher t refractometers : r2i300, AR5, Mark III, AR9
Gradient II - Translucent: fruit juice, corn syrup, antifreezeReicher t refractometers: r2i300, AR5, Mark III, AR9
Gradient III - Opaque: vegetable juice, tomato paste, coffeeReichert refractometers: r2i300, AR5, AR9
Gradient IV - Solid Samples: film, plastics, glassReichert refractometer: Mark III
4 Refractometer, Measuring Manually or Automatically Do you prefer a manual or automatic instrument? Transmission style (manual) is where a sample is placed between the measurement prism and the operator aligns the shadowline to the cross hair target by turning a control knob. Reflection style (automatic) is where the operator places the sample and pushes a Read/Measure button. Manual refractometers are often preferred in educational locations and both styles are used in research.
5 Prism Material Makes a Big Difference Which kind of prism? Reichert offers three different optical prisms. Glass prisms are the most economical but have limited durability. Sapphire prisms are more durable and four times harder than glass. Sapphire prisms are ideally suited for demanding applications and less likely to be damaged. The hardest prism is the YAG (Yttrium Aluminum Garnet) prism with an exceptional refractive index range.
6 SoftwareIs start-up time a factor? When selecting a refractometer, ensure the software features meet your needs. Reichert refractometers offer an intuitive, simple interface for quick and accurate measurements. The software is flexible providing custom scales and methods, and is compliant with 21CFR Part11.
AR9 AR5 r2i300 Abbe Mark III
Measuring Scales RI, % Brix, and 1,000 user defi ned RI, % Brix, or 1 user defi ned RI, % Brix, and 7 user defi ned RI, % Brix, and 14 user defi ned
Measuring Range 1.32000 to 1.70000 RI 1.3200 to 1.5800 RI 1.3330 to 1.5600 RI 1.3106 to 1.7000 RI
0.00 to 100.00 % Brix 0.0 to 100.0 % Brix 0.0 to 95.0 % Brix 0.0 to 95.0 % Brix
Accuracy 0.00002 RI 0.0001 RI 0.0001 RI 0.0001 RI
0.02 % Brix 0.05 % Brix 0.1 % Brix 0.1% Brix
Measurement Mode Continuous Continuous Single Single
Measurement Method Automatic Automatic Automatic Manual
Automatic Temperature +50 to +1000C +50 to +500C +150 to +400 C +100 to +400C
Compensation
Temperature Control Peltier +50 to +1000C Peltier +200 or +250C None/Ambient optional H2O bath +100 to +800C
Method
Prism YAG (Yttrium Aluminum Garnet) Sapphire Sapphire Glass
Light Source Lifetime LED, 589nm fi lter Lifetime LED, 589nm fi lter Lifetime LED, 589nm fi lter Lifetime LED
Display Universal Display 7” Compact LCD display Color touchscreen LCD Display
color touchscreen
Sample Type liquid/gel/paste liquid/gel/paste liquid/gel/paste liquid/gel/solid
Transparent Transparent Transparent Transparent
Translucent Translucent Translucent TranslucentOpaque Opaque Opaque
Reichert Refractometers
Corporate Offi ce Reichert Technologies3362 Walden Avenue, Suite 100Buff alo, New York 14043USA
Customer Service and Technical SupportToll Free (USA): 1-888-849-8955Phone: 1-716-686-4500
European Service CenterAMETEK GmbHReichert Business UnitCarl-von-Linde-Strasse 4285716 Unterschleissheim / Munich, Germany Tel: +49 (89) 315 89110 Fax: +49 (89) 315 891 99 www.Reichertai.com
Reichert Refractometers represent more than 150 years of innovative development and manufacturing expertise.