Hanna Instruments HI 96811 Instruction Manual

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Hanna Instruments HI 96811 Instruction Manual Manual pdf 5 page image

5%Brix, °Baumé, °Oechsle, °KMW and % potential alcohol determinations are made by measuringthe refractive index of a solution. Refractive Index is an optical characteristic of a substance and thenumber of dissolved particles in it. Refractive Index is defined as the ratio of the speed of light inempty space to the speed of light in the substance. A result of this property is that light will “bend”,or change direction, when it travels through a substance of different refractive index. This is calledrefraction.When passing from a material with a higher to lower refractive index, there is a critical angle atwhich an incoming beam of light can no longer refract, but will instead be reflected off the interface.The critical angle can be used to easily calculate the refractive index according to the equation:sin (θcritical ) = n2 / n1Where n 2 is the refractive index of the lower-density medium; n 1 is the refractive index of thehigher-density medium.In the Hanna wine measurement refractometers, light from an LED passes through a prism in contactwith the sample. An image sensor determines the critical angle at which the light is no longerrefracted through the sample.Specialized algorithms then apply temperature compensation to the measurement and convert thisrefractive index to the model specific measurement unit.PRINCIPLE OF OPERATIONQAQC LAB WHITE STONE VA 22578TEL (804) 318-3686