[188.8.131.52.4] A medium in which the transmission is mainly regular and which usually has a high regular transmittance in the spectral range of interest.*
Note: Objects may be seen distinctly through a medium that is transparent in the visible region, if the geometric form of the medium is suitable.
* International Lighting Vocabulary, CIE S 017/E:2011. Vienna, Austria: International Commission on Illumination; 2011.« Back to Definitions Index