Calibration(redirected from calibration of radiography unit)
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calibration(kal-ă-bray -shŏn) A procedure carried out on a measuring instrument, such as a radio telescope, by means of which the magnitude of its response is determined as a function of the magnitude of the input signal. The calibration of a radio telescope provides an absolute scale of the output deflection against antenna temperature.
a metrological operation by which an instrument of measurement (a standard or measuring device) is equipped with a scale or a calibration chart (curve). The graduations on the scale must correspond with the required accuracy to the values of the quantity being measured; the chart (curve) must reflect with similar accuracy the connection between the magnitude produced at the output of the device and the magnitude affecting the input—for example, the dependence of the electromotive force of a pyrometer’s thermocouple on the temperature of the operating junction. Calibrations are made by means of measurement that are more precise than the means of measurement being calibrated; the actual values of the measured quantity are established from the more precise means of measurement. Accurate means of measurement are calibrated individually; the less accurate ones are supplied with a standard scale printed beforehand or a standard calibration chart (curve). The use of such scales and standard calibration charts may at times make it necessary to regulate the means of measurement in order to reduce the error to some established norm.
K. P. SHIROKOV
verification of a measure or set of measures by taking a group of measurements.
Calibration consists in determining the error or correction of a group of gauges (such as a set of weights) or of a single multivalent gauge (such as a linear scale) for various combinations of the gauge or for various ranges of the scale. A comparison is made of the measures or of the sections of the scale in which one of the measures or scale values is taken as the basis of comparison.
REFERENCESMalikov, M. F. Osnovy metrologii, part 1. Moscow, 1949.
Amatuni, A. N. “Kalibrovka podrazdelenii shtrikhovykh mer.” In En-tsiklopediia izmerenii, kontrolia iavtomatiki (EIKA), issue 6. Moscow-Leningrad, 1966. Page 33.