refractometer
refractometer An instrument used to determine refractive index. Several types are available. (a) The Herbert Smith refractometer measures the critical angles by total internal reflection, using a glass hemisphere through which light is directed upwards and reflected from the mineral surface. The reflected beam produces an image in the observing telescope, where a graduated scale measures the critical angle. The refractive index is then calculated by Snell's law. (b) The Abbé refractometer is used primarily for determining the refractive index of liquids. It consists of a pair of glass prisms with a film of liquid between them. The line of the critical angle is measured through a fixed telescope and the refractive index is read off a graduated scale calibrated against a glass plate of known refractive index. (c) The Leitz-Jelley refractometer is used to determine the refractive index of small amounts of liquid. It consists of a glass prism cemented to a glass slide which can hold the liquid. A beam of light is directed at right angles to the glass and is refracted by the liquid on to a graduated scale from which the refractive index can be read.
refractometer
re·frac·tom·e·ter / riˌfrakˈtämətər; rē-/ • n. an instrument for measuring a refractive index.DERIVATIVES: re·frac·to·met·ric / riˌfraktəˈmetrik; ˌrē-/ adj.re·frac·tom·e·try / -trē/ n.
refractometer
refractometer Instrument to measure the refractive index.
More From encyclopedia.com
Cephalic Index , cephalic index n. a measure of the shape of a skull, commonly used in craniometry. Moisture Index , Skip to main content
moisture index therapeutic index , therapeutic index (therapeutic window) The therapeutic usefulness of a drug, expressed as a ratio of the maximum nontoxic dose and the minimum effect… Index Fossil , index fossil (index species, zone fossil) Fossil whose presence is chosen to denote the zone in which it occurs and after which the zone is named. In… Refractive index , refractive index (n) When light travels from air into a substance its velocity is reduced. The light path is also refracted into the substance, and t… Consistency Index , consistency index In cladistic analysis, a measure of homoplasy in a phylogenetic tree (or cladogram), calculated as the number of steps (i.e. charac…
About this article
refractometer
All Sources -
You Might Also Like
NEARBY TERMS
refractometer