Physics:Remission (spectroscopy)

Remission (lat. remittere), in spectroscopy, is the reflection or scattering of light by a material. Similar to the word "re-emission", it is the light which is scattered back from a material, as opposed to that which is "transmitted" through the material. The word "re-emission" connotes no such directional character. Based on the origin of the word "emit", meaning "to send out or away", "re-emit" means "to send out again", "transmit" means "to send across or through", and "remit" means "to send back". It is relevant to spectroscopic absorption measurements of solid samples by diffuse reflectance, for instance DRIFTS and DR-UV-vis.