Endre Mester, a Hungarian physician, and surgeon, is credited with discovering the biological effects of low power lasers, which happened a few years after the 1960 invention of the ruby laser and the 1961 invention of the helium-neon (HeNe) laser.
Mester founded the Laser Research Center at the Semmelweis Medical University in Budapest in 1974 and continued working there for the rest of his life. His children continued his work and imported it to the United States.
By 1987 companies selling lasers claimed they could treat pain, accelerate healing of sports injuries, and more, but there was little evidence for this at that time.
Mester originally called this approach “laser biostimulation”, but it soon became known as “low-level laser therapy” or “red light therapy”. With light-emitting diodes adapted by those studying this approach, it then became known as “low-level light therapy”, and to resolve confusion around the exact meaning of “low level”, the term “photobiomodulation” arose.