| 释义 |
densitometer
den·si·tom·e·ter D0134100 (dĕn′sĭ-tŏm′ĭ-tər)n.1. An apparatus for measuring the optical density of a material, such as a photographic negative.2. See densimeter.
[densit(y) + -meter.]
den′si·tom′e·try (-trē) n.densitometer (ˌdɛnsɪˈtɒmɪtə) n (General Physics) an instrument for measuring the optical density of a material by directing a beam of light onto the specimen and measuring its transmission or reflection densitometric adj ˌdensiˈtometry nden•si•tom•e•ter (ˌdɛn sɪˈtɒm ɪ tər)
n. an instrument for measuring the density of photographic negatives. [1900–05] den`si•to•met′ric (-təˈmɛ trɪk) adj. den`si•tom′e•try, n. densitometeran optical device for measuring the density of a photographic negative.See also: PhotographyThesaurus| Noun | 1. | densitometer - a measuring instrument for determining optical or photographic densitymeasuring device, measuring instrument, measuring system - instrument that shows the extent or amount or quantity or degree of somethingmicrophotometer - special kind of densitometer that measures density variations over a very small area | | 2. | densitometer - a measuring instrument for determining density or specific gravitydensimeterdasymeter - densimeter consisting of a thin glass globe that is weighed in a gas to determine its densitymeasuring device, measuring instrument, measuring system - instrument that shows the extent or amount or quantity or degree of something |
Translationsdensitometer
densitometer (den-să-tom -ĕ-ter) An instrument for measuring the density of exposure of a photographic emulsion. Densitometers have a light source and photocell to measure the transmission (or reflection) of the sample. They are used in obtaining quantitative measurements from photographic records of spectra, diffraction experiments, etc.DensitometerA photometer for measuring the optical density (the opposite of transmittance) of materials.Densitometer a device for measuring the optical density of developed photographic materials. They are classified according to the method of measurement (direct readout and the comparison principle), the type of light receiver (the eye, a photocell, or a photomultiplier), the type of output data (nonrecording devices and automatic recording devices), and the magnitude of the field being measured (densitometers proper, as compared with microdensitometers, which are sometimes referred to as microphotometers). In devices with direct readout, a single light beam whose initial strength Φ0 is compared with the strength Φ of the beam after passage through a photosensitive layer is usually used. Devices whose operation is based on the comparison method have two light beams originating from the same source, one of which is the measuring beam and the other is the reference beam. In the most widely used type of photoelectric densitometer, the two beams are directed at two photoelectric receivers that are in a difference-reading circuit (that is, if the strength of the two beams is equal, the signal of the two receivers is zero) or are alternately connected to the same receiver. The difference signal, which is caused by unequal strength of the two beams, is brought to a zero reading with the aid of a variable light attenuator (for instance, a gray photometer wedge) inserted into one of the beams being compared and calibrated in units of optical density D = log Φ0/Φ. The accuracy of densitometer measurements averages ±0.02 optical density units over the entire measurement range. For the best models the range is 5-6 density units; for relatively simple devices it is 2.5-3.0 density units (transmission coefficients of 10-5-10-6 and 0.003-0.001, respectively). The most typical densitometer models made in the USSR are the DFE-10 nonrecording wedge densitometer with selenium photocells (Dmax = 3.0) and the IFO-451 recording wedge microdensitometer with a photomultiplier, which is capable of measuring optical densities up to 2.5 units. REFERENCEGorokhovskii, Iu. N., and T. M. Levenberg. Obshchaia sensitometriia: Teoriia i praktika. Moscow, 1963.IU. N. GOROKHOVSKII densitometer[‚den·sə′täm·əd·ər] (engineering) An instrument which measures optical density by measuring the intensity of transmitted or reflected light; used to measure photographic density. densimeter densitometeri. An instrument for measuring the density or specific gravity of fuel. Also called a densimeter.
ii. An instrument for measuring the optical density (photographic transmission, photographic reflection, visual transmission, etc.) of a material, generally of a photographic image.densitometerA device that calibrates the relative strength of a color using complementary filters. Contrast with colorimeter.densitometer
densitometer [den″-sĭ-tom´ĕ-ter] 1. an instrument for determining density or specific gravity of a liquid.2. an instrument used to measure the degree of exposure (darkening) on photographic or x-ray film.den·si·tom·e·ter (den'si-tom'ĕ-tĕr), 1. An instrument for measuring the density of a fluid. Synonym(s): densimeter2. An instrument for measuring, by virtue of relative turbidity, the growth of bacteria in broth; useful in microbiologic assay of nutrients and antibiotics, phage studies. 3. An instrument for measuring the density of components (for example, protein fractions) separated by electrophoresis or chromatography, using light absorption or reflection. 4. An electronic instrument for measuring the blackening of radiographic film by x-ray exposure; used for film sensitometry, bone densitometry, measurement of line spread function (microdensitometer). 5. An instrument for measuring the extent to which a material absorbs or reflects light. [L. densitas, density, + G. metron, measure] densitometer (dĕn′sĭ-tŏm′ĭ-tər)n.1. An apparatus for measuring the optical density of a material, such as a photographic negative.2. See densimeter.
den′si·tom′e·try (-trē) n.den·si·tom·e·ter (dens'i-tom'ĕ-tĕr) 1. An instrument for measuring the density of a fluid.
Synonym(s): densimeter. 2. An instrument for measuring, by virtue of relative turbidity, the growth of bacteria in broth; useful in microbiologic assay of nutrients and antibiotics and phage studies. 3. An instrument for measuring the density of components (e.g., protein fractions) separated by electrophoresis or chromatography, using light absorption or reflection. 4. An electronic instrument for measuring the blackening of radiographic film by x-ray exposure; used for film densitometry, bone densitometry, measurement of line spread function (microdensitometer). [L. densitas, density, + G. metron, measure]den·si·tom·e·ter (dens'i-tom'ĕ-tĕr) 1. An instrument for measuring the density of a fluid.2. An instrument for measuring the growth of bacteria in broth. 3. An instrument for measuring the density of components separated by electrophoresis or chromatography, using light absorption or reflection. 4. An electronic instrument for measuring the blackening of radiographic film by x-ray exposure; used for film densitometry and bone densitometry. [L. densitas, density, + G. metron, measure]densitometer
Synonyms for densitometernoun a measuring instrument for determining optical or photographic densityRelated Words- measuring device
- measuring instrument
- measuring system
- microphotometer
noun a measuring instrument for determining density or specific gravitySynonymsRelated Words- dasymeter
- measuring device
- measuring instrument
- measuring system
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