transparent medium
medium in which the transmission is mainly regular and which usually has a high regular transmittance in the spectral range of interest
Note 1 to entry: Objects can be seen distinctly through a medium which is transparent in the visible region, if the geometric form of the medium is suitable.
Note 2 to entry: This entry was numbered 845-04-108 in IEC 60050-845:1987.
Note 3 to entry: This entry was numbered 17-1340 in CIE S 017:2011.