Refractometer Sample Cover options for Rudolph J157 Models and Above
Rudolph Research Analytical sample cover, pioneered dual temperature control for automatic refractometers and still remains a market leader in this all-important technology. Refractive Index varies with temperature. However, this variation depends on the sample but for a refractometer to give an accuracy of 0.0001 the temperature variation has to be less than 0.5C.
EP Refractometer Sample Cover
The EP sample cover is great for applications where the measurement temperature is near ambient. Importantly, the cover is a single unpowered piece and temperature control is provided only from below the sample.
CC Refractometer Sample Cover
The (CC) concave sample cover is controlled to the same temperature as the prism. When lowered provides the upper part of a temperature controlled micro environment that totally surrounds the sample. Thus, it provides unrivaled temperature stability, fast measurement time and minimal evaporation.
CP Refractometer Sample Cover 
The (CP) contact presser spreads the sample out evenly over the measurement area. Therefore, it is ideal for extremely viscous samples like heavy syrups and resins that need a thin layer for the best measurement results.