Rudolph Automatic Refractometer J-series using Internal Reflection Refractometer on scratch proof artificial sapphire prisms that measure the reflected light and not the transmitted light, like the Abbe, so dark and viscous samples measure as easily as clear samples.

Just put a drop of sample on the prism, press measure and walk away. No shadow line, no manual balancing or interpretation.

There are more than 10 different Refractometer model variations for high throughtput, high accuracy applications across vario us industries: Pharmaceutical, Flavor, Fragrance Essential Oil, Chemicals, Food, Petroleum, Beverage, Cosmetics.


  • J47



    • Very fast measuring food and beverage industry refractometer (Refraktometer)
    • On-board temperature correction using the latest ICUMSA tables.
    • Simple to load, simple to measure, simple to clean
    • Result independent of operator judgement
    • The J47 is part of the Rudolph Research line of Laboratory Refractometers.
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  • J57HA


    Refractometer-Rudolph’s Digital J57HA Heavy Use, High Accuracy, QC Instrument for Food Quality Testing. The Rudolph J57HA refractometer was designed to meet the unique needs of food quality testing where the automatic refractometer is viewed as a quality control (QC) tool rather than a laboratory instrument. A single flat measurement surface, automatic electronic temperature control, and one button measurement capability make it perfect for heavy use food industry applications, where fast, automatic, and accurate Brix readings are required.
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  • J57WR


    Automatic Refractometer J57WR - Wide Measurement Range for the Chemical Industry. The Rudolph J57WR Automatic Digital Refractometer (Refraktometer) was designed to meet the unique needs of industrial environments in the chemical industry where the refractometer is viewed as a Quality Control (QC) tool rather than a laboratory instrument. A single flat measurement surface, automatic electronic temperature control and one button measurement capability make it perfect for heavy use applications where fast, automatic, and accurate readings are required.
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  • J57AB/J157AB


    Refractometers - Automatic, Digital J57AB & J157AB designed for the Petroleum Industry. The Rudolph Research J57AB and J157AM refractometers have temperature control and WU measurement features needed for testing required in the petroleum industry.
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  • J57TPN


    Refractometer- J57TPN for Hospital Pharmacies to monitor IV Therapies and controlled substances. The Rudolph Research J57TPN refractometer is intended for use in hospital pharmacies and Compounding Labs to monitor the quality of parenteral nutrition mixtures, Intravenous therapy (IV), and ensure compliance with USP<797>. It is also useful in preventing the diversion of narcotics, and other controlled materials. The J57TPN pharmacy refractometer provides a fast, easy to use way to check on materials returned from the operation theatre or incorrectly issued from the pharmacy.
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  • J157


    Digital Refractometer - J157 High Accuracy for Food, Beverage, Water Based Chemicals, & Sugar Industries. Rudolph Research Analytical, working together with refractometer (Refraktometer) users from various countries and disciplines, has developed the J157 Automatic Digital Refractometer. The Rudolph J157 benchtop combines features and accuracy that meet the most demanding applications both in and out of the laboratory.
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  • J157-633


    Automatic Refractometer, J157-633 for Biotechnology and Bioengineering Research A Biotechnology and Bioengineering refractometer designed specifically for measuring materials in the Optical Waveguide Lightmode Spectroscopy (OWLS) system thus capable of measuring the effective refractive index of a thin layer above an Si(Ti)O2 waveguide surface. The Digital J157-633 has all of the same features as the standard J157 automatic refractometer but operates at 633nm instead of the standard 589nm. The J157-633 shares these features with the J157 Automatic Refractometer.
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  • J257


    Automatic Refractometer, Rudolph J257 with Wide-Range Measurement Rudolph Research Analytical, working together with refractometer users from the polymer, petroleum, petrochemical, pharmaceutical and essential oil industries, has developed the J257 Wide Range, Automatic Refractometer. The J257 is a Digital, Bench-top Refractometer, featuring electronic cooling and heating with an extended refractive index (RI) measurement range.
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  • J357


    Automatic Refractometer, J357 Offers Highest Performance for Research Labs. Designed as a research quality instrument the Rudolph J357 Automatic Digital Refractometer has the highest performance of any refractometer in the Rudolph range. This instrument offers the same extra wide RI measurement range as our chemical industry refractometer models combined with the high accuracy of our food industry refractometer models. It also offers the most powerful automatic electronic temperature control (heating and cooling) and is able to make RI and BRIX measurements at up to 120 °C. The J357 is a perfect choice for the most demanding pharmaceutical, chemical, petroleum, essential oils, fragrance and cosmetic refractometer USERS.
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  • J457


    Refractometer, Rudolph’s J457 with Smart Measure™ Technology Improves Results! All 3 models of the J457 Electronic, Digital, Refractometers come with Smart Measure™ Technology that virtually insures accurate Refractive Index (RI) and BRIX, measurements by automatically detecting when the prism is improperly cleaned, insufficient sample is loaded, or if the instrument is improperly calibrated. Various configurations are available for a small footprint, wall mount, or a remote-read factory configuration. All models come with a digital touch screen, and our Dual Temperature Control System utilizing Peltier Technology.
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  • Rudolph Research Analytical
  • Novasina
  • 3NH Colorimeter
  • Triowin