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Related to absorptance: transmittance


 (əb-zôrp′təns, -sôrp′-)
The ratio of absorbed to incident radiation.


(əbˈsɔːptəns; -ˈzɔːp-) or

absorption factor

(General Physics) physics a measure of the ability of an object to absorb radiation, equal to the ratio of the absorbed radiant flux to the incident flux. For a layer of material the ratio of the flux absorbed between the entry and exit surfaces of the layer to the flux leaving the entry surface is the internal absorptance. Symbol: α Compare reflectance, transmittance
[C20: absorption + -ance]


(æbˈsɔrp təns, -ˈzɔrp-)

the ratio of the amount of radiation absorbed by a surface to the amount of radiation incident upon it.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.absorptance - a measure of the rate of decrease in the intensity of electromagnetic radiation (as light) as it passes through a given substanceabsorptance - a measure of the rate of decrease in the intensity of electromagnetic radiation (as light) as it passes through a given substance; the fraction of incident radiant energy absorbed per unit mass or thickness of an absorber; "absorptance equals 1 minus transmittance"
coefficient - a constant number that serves as a measure of some property or characteristic
References in periodicals archive ?
From the measured albedo, transmittance, and absorptance spectra, cloud properties (optical thickness, thermodynamic phase, effective radius) can be derived that are averaged over the SSFR hemispherical footprint.
015 Radius of the cylinder receptor Table 3: Necessary values to calculate the optical efficiency Parameter Nomenclature Value Receptor absorptance [rho]c 0.
In a-Si:H solar cells, the measured quantum efficiency can be directly compared to the absorptance in i-layer, considering ideal extraction of charge carriers from the i-layer and neglecting the contribution from defect-rich p- and n-layer [8].
Consequently, empirical models for prediction of chlorophyll content from reflectance are largely based on reflectance in the 550 or 700 nm regions where higher chlorophyll contents are required to saturate the absorptance (Buschman and Nagel, 1993).
Note that grass, even when it is green, has a greater solar absorptance than a white membrane.
Absorptance Spectra of the Er(III)- and Yb(III)-Doped Samples
II] raise some difficulties and generally the former is calculated from the incident PFD assuming a leaf absorptance of 0.
This transfer-matrix method has been used to analyze reflectance, transmittance, and absorptance of optical multilayer accurately.
Thus spectral issues related to cavity absorptance are probably very small to begin with (at least for pre-flight cavities) and have already been corrected.
2000) were used to calculate the absorptance curve that produced a minimum sum of squares fit to the spectral sensitivity data (Stavenga et al.