ATR-L Dispersion Refractometer

Multiple wavelength digital refractometer.

The ATR-L is a digital, fully automatic spectral refractometer used to determine the refractive index of liquids of various viscosities regardless of opacity or color. The stainless steel measuring head allows for a minimum sample volume of 0.3 ml and is separate from the electronic control unit.

The ATR-L includes a built-in Peltier system and a precision thermometer for fast, precise temperature control. The use of discrete LEDs provides automatic dispersion measurement between 350nm and 1000nm at seven wavelengths making it possible to implement any combination of customer-specified wavelengths within the instrument and carry out quasi-spectral measurements in close to real-time.


  • High-precision refractometer
  • Automatic dispersion measurement
  • Seven fixed wavelengths with the full range of visible light
  • Automatic ABBE number measurement
  • Internal Peltier temperature control
  • Able to discriminate ingredients with the same refractive index
  • Measures liquids and solids
  • Ideal for research and development

The ATR-L multi-wavelength refractometer can be used to determine product purity and is therefore ideally suited for determining sample quality. Material characterization can be used to determine the quality of products such as perfume, wine, or other alcoholic beverages. With an available cover for the measurements of solid samples, quality control of hydrophobic and hydrophilic intraocular lenses (IOL) is possible.

Since the measuring principle is also sensitive to absorption, the measurement not only provides information about the content of the analyte but also valuable information about color and turbidity.

Applications for the ATR-L Refractometer are possible in research and development, medical research, plastic lenses, contact lenses, proteins, communication technology, polymer materials, special optical liquids, glasses, and adhesives.

Measuring scales Refractive index (RI)
Measuring range 1.33200 – 1.70000 RI* / 100% Brix
Resolution 0.00001 RI* / 0.01 Brix
Precision ± 0.00004 RI* / ± 0.03 Brix
Reproducibility ± 0.00004 RI* / ± 0.03 Brix
Measuring time per sample 20 sec for all 7 wavelengths after temperature stabilization; single sample measurement
Ambient temperature + 15° to + 40°C
Automatic temp. compensation Operational temperature Temperature stability
Temperature precision
Solid state Peltier-thermostatisation
+ 10°C to + 80°C
± 0.03°C
Detector CCD-linear array with 2048 elements
Sample compartment Used materials: stainless steel, Black Delrin®, Teflon®, Viton®, FFKM sealing
Prism YAG
Prism YAG
Light source/wavelength 7 discrete LED’s with fixed wavelengths 400, 450, 490, 545, 590, 660, 700 nm (others on request), wavelength accuracy ± 2 nm
Display LCD, 16 x 16 characters, back-illuminated
Operation 20 key membrane including function keys
Interfaces /Communication 1 x RS232 C, 1x parallel, USB optional
Standards European and international Pharmacopoeia, various ASTM, ISO, and DIN standards
Dimensions / Weight Measuring head, stainless steel: 260 x 190 x 220 mm (w x h x d); control unit: 220 x 110 x 290 mm (w x h x d); complete unit 8 kg

Accessories, Spares, Calibration and Training