transmission density vs optical density

transmission density and optical density both are nouns.

Word	Noun	Adjective	Verb	Adverb
transmission density	Yes	No	No	No
optical density	Yes	No	No	No

As nouns, transmission density and optical density are synonyms defined as:

transmission density and optical density: (physics) a measure of the extent to which a substance transmits light or other electromagnetic radiation

Other synonyms of transmission density include absorbance, photographic density.

transmission density (noun)	optical density (noun)
(physics) a measure of the extent to which a substance transmits light or other electromagnetic radiation	(physics) a measure of the extent to which a substance transmits light or other electromagnetic radiation