transmittance

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transmittance 

A measure of transmission expressed as the ratio of the intensity of the transmitted light I′ to the intensity of the incident light I, for a specified wavelength, i.e. T = I′/I. It is usually given as a percentage, i.e. T = I′/I ✕ 100. Syn. total transmittance. See absorbance; optical density.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann
References in periodicals archive ?
Note that the [Q.sub.0] for a unit temperature difference can be calculated by multiplying the tabulated clear field thermal transmittances ([Q.sub.0]) total by the projected surface area of the envelope (Q/[DELTA]T=UA).
X-ray diffraction (XRD) pattern, surface morphology observation, hall measurement, and optical transmittance ratio were used to monitor the changes in the structural, optical, and electrical properties.
Based on the rigorous coupled-wave analysis (RCWA) method, we calculate the transmittance of the designed bilayer films and discuss the optimum structure as a compromise between UV protection and visible-light transparency.
where I represents the intensity of the image observed, J represents the intensity of scene light, A represents the atmospheric light at infinity, and t is known as transmittance. The first equation item J(x)t(x) is an attenuation term, and A(1 - t(x)) is an atmospheric light item.
The running results show that the FTIR transmittances of the characteristic common peaks of the same species are stable.
Observations of zenith sky transmittance and global and diffuse short-wave radiative fluxes carried out over two stations, (i) Chiba (35.7[degrees]N, 139.7[degrees]E), an urban site in Japan, and (ii) Cape Hedo (26.87[degrees]N, 128.25[degrees]E), amarine environment as part of the SKYNET (http://atmos.cr.chiba-u.ac.jp/) programme, [12] have been used in the present study.
where [tau.sub.gb] and [tau.sub.gb] are the direct and diffuse glazing illuminance transmittance; [tau.sub.sh] is the visible transmittance of interior roller shade; [[??].sub.sh] is the visible reflectance of interior roller shade; and [[??].sub.gd.sup.b] is the back side glazing diffuse reflectance.
As mentioned above, the aim of this project was to determine the reliability of the calculation method, presented in the standard (EN ISO 6946:1997), used for calculating the influence of air gaps on thermal resistance of horizontally laid thermal insulation layers, compare these results with the measurements of thermal conductivities and to determine the corrections to thermal transmittance value of horizontally laid thermal insulation, which is enlarged due to the formed air gaps.
At the University of Basel in Switzerland, an experimental setup to measure wavelength and angular dependent direct-direct transmittances and reflectances of glazing was constructed (Steiner et al.
The reflectance (R) and transmittance (T) of a thick free standing film are expressed as follows, respectively (1):