Light conversion efficiency of calcium tungstate using a light intensifier tube.
A technique which may be used to determine the light conversion efficiency (defined below) of thin fluorescent crystals is presented. The illuminance associated with the visible spectrum emitted by the material under a pulse of x rays and incident on a light intensifier tube is amplified by the tube and is eventually recorded by a photographic film placed on the other side of the tube. A calibration curve relating the conversion efficiency of the crystal (regarded as an unknown variable) and the resulting film density is first obtained analytically. This is then used, in conjunction with the experimentally measured film density, to yield the conversion efficiency. An application of this technique was made to the case of a calcium tungstate crystal, for which a conversion efficiency of [equiation] was determined.
Alloucherie
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