Different models of traditional analog refractometers have different internal scales on which to read fluid concentrations. Some instruments have specialized scales that indicate the exact mixture of the sample being tested, while others have an arbitrary unit of measure that works like a shorthand for refractive index measurements.
The instruction manual that comes with each refractometer carefully explains the procedure for comparing refractometer readings to the actual known concentrations or properties of your specific fluid. Trained MISCO technical support engineers are always available to assist you at any time.
You may find answers to your application issues in the MISCO Refractometer forum.
MISCO refractometers are easy-to-use and require little or no training. They can be mastered by ANYONE in just minutes.
Light passing through a liquid is slowed compared to the speed it travels in air. So once a fluid sample is placed on the measuring surface of a refractometer, the light passing through it slows and is bent.
The refractometer focuses this bent light on a tiny internal scale. The scale is magnified by the eyepiece lenses so it is easily visible.
The optics are supported by a bi-metal strip that moves lenses in response to temperature changes, ensuring that readings are accurate regardless of temperature.