The Polarimeter is used for determining the optical rotation of substances. By measuring optical rotation, the concentration, content, purity etc of certain substances can be found out. Therefore, the Polarimeter has become one of the most useful instruments in laboratories of sugar industry, pharmaceutical industry, oil refining, foodstuff industry, chemical industry, universities and scientific research field.
Major modules in our Polarimeter include light source, Interference filter, polarizer, faraday modulator, sample chamber, analyzer and Detector.
Unpolarized light from light source (Sodium vapour lamp) passes through an interference filter and polarizer so that a fixed wavelength polarized light comes out. This polarized light enters the Faraday Modulator and then passes through the sample cell. The modulated light which passed through the sample cell enters a second polarizer, known as the “Analyzer,” which detects the angle of rotation. Finally, the light falls on a photomultiplier tube which converts the light intensity to an electric signal.
Optical wavelength : 589 nm (Na D-line)
Measuring range : ± 180° (Switchable)
Resolution : 0.001 Deg.
Repeatability : ± 0.03 Deg.
Accuracy : ± 0.03 Deg.
Sugar Scale Range : ± 259°Z
Resolution : ± 0.01°Z
Repeatability : ± 0.1°Z
Accuracy : ± 0.1°Z
Measuring modes : Optical Rotation, Specific rotation, Concentration,
Optical Purity & Sugar Scale.
Sample chamber : Accepts sample cells up to 200mm Length
Principle : Symmetric angular oscillation optical null principle.
User interface : 5.7 inch Graphical LCD & Keyboard and PC Software
PC Interface : RS232
Calibration : Automatic calibration by push button
Detector : PMT
Dimension : 625 x 335 x 270 mm h
Weight : 30 Kg (Approx.)
Power requirement : AC100- 230 V 50 Hz
Optical rotation is directly proportional to path length; the longer the tube, the greater the overall accuracy. Holmarc’s Polarimeter accepts tubes up to 200mm long. A 200mm sample tube offers twice the sensitivity when measuring the same solution in a 100mm sample tube. Different types of sample tubes are available up to 200mm length.