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Related to transmittance: absorbance, Thermal transmittance


 (trăns-mĭt′ns, trănz-)
1. A transmission.
2. Physics The ratio of the radiant energy transmitted to the total radiant energy incident on a given body.


1. the act of transmitting
2. (General Physics) physics Also called: transmission factor a measure of the ability of anything to transmit radiation, equal to the ratio of the transmitted flux to the incident flux; the reciprocal of the opacity. For a plate of material the ratio of the flux leaving the entry surface to that reaching the exit surface is the internal transmittance. Symbol: τ Compare reflectance, absorptance


(trænsˈmɪt ns, trænz-)

Physics. the ratio of the radiant flux transmitted through and emerging from a body to the total flux incident on it: equivalent to 1 minus the absorptance.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.transmittance - the fraction of radiant energy that passes through a substancetransmittance - the fraction of radiant energy that passes through a substance
coefficient - a constant number that serves as a measure of some property or characteristic
References in periodicals archive ?
The lack of significant increase in light transmittance after the snow cover had been removed in April is explained by the relatively thin snow cover and its relatively low reflectance and attenuation coefficient.
The design of proper daylighting in buildings is coupled mainly with a window design and its glass transmittance [McMullan 2007; Szokolay 2008; Baker & Steemers 2002; Evans 1981] in the response with external daylight conditions.
In the 1980s, the integrating sphere spectrophotometer was introduced to accurately measure the total transmittance of systems where the transmission depends on the angle of the incident light.
0283 x A x (100-B) [less than or equal to] 40 (I) (wherein A is a nitrogen adsorption specific surface area and B is a light transmittance of toluene extract).
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.
Low-E coatings can combine the advantages of a reduced U-factor and SHGC while maintaining high levels of visible light transmittance.
The researchers suggest that daylighting and shading effects can be optimized by using their formula and choosing appropriate windows size and positioning as well as other parameters, such as glazing transmittance.
PPG Industries aerospace transparencies business is developing coating technology for aircraft cockpit and passenger-cabin windows that reduces solar heat transmittance for more crew and passenger comfort and reduced load on the air-conditioning system for lower operating costs.
Oriented polypropylene is used in almost the same market as non-oriented polyethylene and has a high market share in areas such as snacks, bread and pastries, sweets and tobacco in which high transmittance, gloss and stiffness are important factors.
5 mil optically clear polyester base, with haze values of less than 3 percent and transmittance greater than 87 percent.
The translucent grade, ExxonMobil TPE F371-60, has a light transmittance of 10 per cent.
The TFT cells are manufactured using high aperture panel technology, high transmittance color filters and high transmission polarizers that result in a clear and bright display that is suitable for high ambient light or outdoor, high brightness applications.