1. Transmissivity is a measure of the ability of a material to transmit radiation, equal to the internal transmittance of the material under conditions in which the path of the radiation has unit length
, 2. Transmissivity is an optical property o … 2. Transmissivity is an optical property of a material, which describes how much light is transmitted through material in relation to an amount of light incident on the material. The light that was not transmitted was either reflected or absorbed. Transmissivity depends on the wavelength of light, direction of the incident and transmitted light, polarization, type of the material, chemical composition and structure of the material, and state of the material and its surface.and state of the material and its surface.