Microdensitometer | Article about microdensitometer by The Free Dictionary
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microdensitometer (mÿ-kroh-den-să-tom -ĕ-ter) An optical instrument that measures and records small changes in the transmission density on a photographic plate, such as the faint features in a spectrum. The plate, mounted on a carriage, is moved through a light beam. A photomultiplier measures the amount of light transmitted by the plate and the output is fed to a chart recorder or computer.
A high-sensitivity densitometer used in spectroscopy to detect spectrum lines too faint on a negative to be seen by the human eye.
References in periodicals archive
The photographs taken on night 2 did not reveal anything unusual despite undergoing microdensitometer
patent for "Spot Microdensitometer
for the Spectral Density Analysis of Film.
The scattered intensities were obtained from the photographic films using a unidimensional microdensitometer
During the 1970s astronomers confirmed this characteristic pattern, now referred to as the "quadrupole azimuthal brightness asymmetry," by scanning scores of photographic plates of Saturn with a microdensitometer
The scattered intensities were obtained from the photographic films using a one-dimensional microdensitometer
CCD cameras have replaced glass plates, image-processing software has supplanted scanning microdensitometers
, and satellite-based star catalogs have eliminated the need to measure star positions six months before or after the eclipse.