URBANA – University of Illinois researcher Nick Holonyak Jr. said he took it as a challenge when some chemists at General Electric criticized his approach to making lasers during a strongly worded conversation in 1962.

“They were telling me I was nuts in pretty foul language – New York language – and I was giving it back in language from the coal fields of southern Illinois,” Holonyak told The (Champaign) News-Gazette.

Holonyak proved his critics wrong when he found a new alloy that would emit light in the red part of the visible spectrum and created the first practical light-emitting diode, or LED.