Laboratory Polarimeter

The laboratory polarimeter which we manufacture is a reliable instrument for accurate measurement of optical rotations, for study of polarisation effects and for quick and easy discrimination between right-handed sugars such as dextrose and left handed sugar such as laevulose. The instruments find use in industries as well as in colleges and universities. We are rated among the top analytical polarimeter manufacturers as well as suppliers.
our measurement polarimeters are essentially consists of a pair of polarizes arrange in a straight line, one of which (analyzer) can be rotated with respect to the other (polarizer) and the rotation measured on a divided circle. The analyzer is rotated till it is crossed with the polarizer. In this position the planes of he polarization of the polarizer and the analyzer, are mutually perpendicular, so that there is no transmission of light across the pair. Now if a tube containing an optically active solution is introduced between the polarizer and the analyzer, the light transmission is partially or wholly (if the optical rotation of the liquid equals90 o ) resorted. The analyzer is rotation again to obtain the no transmission position. This rotation equals the optical rotation of the liquid.
Since it is difficult to recognize the actual no transmission position, one is able to obtain a range only for no transmission. The definition of this range is quite subjective. To overcome this difficulty, in modern polarimeters, an extra device is used. This device is a half-wave plate, covering half of the circular field of view. This plate introduces a certain path difference between light waves in the two halves of the field of view. Thus when the analyzer is rotated the intensity in one half of the field of view is extinguished slightly before the other half. At this point it is easy to continue rotation of the analyzer to obtain a uniform illumination of the field of view. This position can be determined quite accurately and is used as the desired position. The optically active substance (solution) is now introduced between the polarizer and the analyzer and the uniform, field of view position is determined again to obtain the optical rotation of the liquid.
The circular scales are finely marked on a 10cm diameter circle both in angular measure and in international sugar scale. The smallest division on angular scale is 1 o iss. The sugar scale is calibrated between 30 o (for levorotary substances) and +130 o iss. A divided of 0.05o (3 minutes) on the angular scale and 0.1 o iss. The scale is properly illuminated to facilitate reading.
Maximum length of tubes which this model can take is 220mm; smaller tubes of course can be used. The tubes supplied have a bubble trap.polaroid sheets used for polarizing the incident lightglass circular scale finely marked in angular degrees and also in iss degrees. The range on iss scale is from30 o + 130 opermanent focus: once the dividing line is focused for the eye. The focus is not disturbed by inserting tubes containing solutions, regardless of the nature of solution or of the length of the tubepermanent good definition even with difficult liquidsrotating half shadow effectprovision for attaching lamp to the instrument thus keeping alignment correct at all times.