object lens vs object glass

object lens and object glass both are nouns.

Word	Noun	Adjective	Verb	Adverb
object lens	Yes	No	No	No
object glass	Yes	No	No	No

As nouns, object lens and object glass are synonyms defined as:

object lens and object glass: the lens or system of lenses in a telescope or microscope that is nearest the object being viewed

Other synonyms of object lens include objective, objective lens.

object lens (noun)	object glass (noun)
the lens or system of lenses in a telescope or microscope that is nearest the object being viewed	the lens or system of lenses in a telescope or microscope that is nearest the object being viewed