Filter

2-2-195

A device which is used to modify, by transmission, the radiant or luminous flux, or the spectral distribution, or both, of the radiation passing through it.

Note: A distinction is made between Selective Filters and Non-Selective Filters according as they do or do not alter the relative spectral distribution of the radiation.

Reference: C.I.E. (modified)

Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)

English