A Historical Perspective of Lasers in Dermatology
Prof. Robert A. Schwartz MD, MPH, DSc (Hon), MAE, FRCP Edin
Rutgers New Jersey Medical School, Newark, NJ, USA
The history of the laser as a fascinating one. We cover it by focusing on two University of
California Berkeley Professors, Charles H. Townes and George C. Pimentel, and two professors
of dermatology, Edmund Klein and Leon Goldman. The term “laser” itself is an acronym for
Light Amplification by Simulated Emission of Radiation. A laser is a device that emits light
through a process of optical amplification based upon the above principle. It was originally
named an optical MASER by Townes and Arthur Leonard Schawlow at Bell Labs in 1957.
Gordon Gould coined the term LASER.
The Maser principle of stimulated emission was proposed by Albert Einstein in 1917. The first
patent filed was dated April 1959 and awarded to Bell Labs in 1960. In 1964 the Nobel Prize in
Physics was awarded to Townes and two Russians: Basov and Prokhorov. In 1960 physicist
Theodore H. Maiman created the first working laser. Six Nobel Prizes have been awarded for
laser work. The ruby laser systems patent filing of April 13, 1961 resulted in issuance on
November 14, 1967. One laser patent battle was most extraordinary: a 28-year patent fight for a
Charles Townes became Professor at the University of California Berkeley in 1967, where he
remained until his passing in 2015 at the age of 99. George C. Pimentel, who served as a Professor
of Chemistry at the University of California Berkeley from 1949-1989, invented the chemical
laser in 1965, pioneering the conversion of chemical energy released as product vibrational
excitation into laser light. He inspired huge numbers of undergraduate students in his inorganic
chemistry course, including at least one future dermatology professor, and many graduate
students and colleagues as well. Dermatology Professor Edmund Klein escaped his native
Vienna at age 17, worked with Nobelist Charles Best while a medical student at the University of
Toronto, and then with Sidney Farber, Walter Lever, and others at Harvard University. Klein
introduced lasers into biomedical research, for which he was honored by the American Society
for Laser Medicine in 1986, although he is better known as the Father of Modern
Immunotherapy and as a Lasker Award recipient. Dermatology Professor Leon Goldman
introduced the laser for treating skin diseases. He has been universally proclaimed as the “Father
of the Medical Laser.”
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Invest Dermatol 43:565-570, 1964.
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Goldman L, Wilson RG: Treatment of basal cell epithelioma by laser radiation. JAMA 189: 773-
Goldman L, Schwartz RA: Lasers in dermatology. In: Skin Cancer Recognition and
Management. RA Schwartz, Springer, Berlin, 1988.