coefficient of reflection vs reflection factor

coefficient of reflection and reflection factor both are nouns.

Word	Noun	Adjective	Verb	Adverb
coefficient of reflection	Yes	No	No	No
reflection factor	Yes	No	No	No

As nouns, coefficient of reflection and reflection factor are synonyms defined as:

coefficient of reflection and reflection factor: the fraction of radiant energy that is reflected from a surface

Other synonyms of coefficient of reflection include reflectance, reflectivity.

coefficient of reflection (noun)	reflection factor (noun)
the fraction of radiant energy that is reflected from a surface	the fraction of radiant energy that is reflected from a surface