Refractive index detector Fresnel method

However, it was the one of the first refractive index detector to work on the Fresnel method. 

A Diagram of the Optical System of a Refractive Index Detector Operating on the Fresnel Method Courtesy of the Perkin Elmer Corporation... 

Fig. 1 A diagram of the optical system of a refractive index detector operating on the Fresnel method.

The Fresnel method of refractive index measurement has also been used in the design of commercially available detectors. The different... 

A second method utilizes the Fresnel principle (Figure 19-44), which relates the transmittance of a dielectric interface to the refractive indices of the interface materials. Such an interface may be formed between a glass prism of selected optical properties and the liquid whose refractive index is to be measured. These detectors are difficult to use with gradient elution systems, and temperature control of the solvents is critical. 

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