Question: What is the name of this American actor, based known for a role on Roseanne, who also starred in Morgan's Ferry?
Sentence (from "Johnny Galecki"): He is known for playing David Healy in the ABC sitcom "Roseanne" from 1992 to 1997 and Dr. Leonard Hofstadter in the CBS sitcom "The Big Bang Theory" since 2007.
Relevant evidence: Yes