Optics & Photonics News

Presidential Profile: Arthur Francis Turner

John N. Howard

Arthur Francis Turner was OSA’s 1968 President and a pioneer in the field of optical interference coatings. He earned many accolades for his work, including a Scientific and Engineering Award from the Academy of Motion Picture Arts and Sciences.

Arthur Francis Turner was born in Detroit, Mich., U.S.A., on 8 August 1906. He received a B.S. from the Massachusetts Institute of Technology ed experimental physicist H. Rubens, thus making Turner a direct link to the beginnings of quantum mechanics and the studies of blackbody radiation by Lummer and Pringsheim.

While still in his 20s, he published a paper with Czerny pointing out the aberration corrections inherent in the now famous Czerny-Turner spectrometer mounting. ;is work went largely forgotten until the Ebert system was rediscovered in 1952. Several years passed before anyone realized that the Czerny-Turner system o;ers an even greater opportunity for aberration correction than does the now equally famous Ebert-Fastie mounting. It was in Czerny’s laboratory that Turner first became acquainted with C. Hawley Cartwright.

John Howard

In 1935, Turner accepted a teaching position at MIT, where he was reunited with Cartwright. ;e two initiated pioneering research on optical interference coatings. A paper they authored in 1939 describes some of the earliest work on stacked quarter-wave films as interference coatings—a prototype of the sophisticated dielectric film stacks used today as low-loss laser reflectors. Cartwright and Turner also developed a technique for depositing invisible coatings on glass to reduce unwanted light reflection.

Turner joined the Bausch + Lomb Optical Company (B+L) in 1939. Under his direction, the optical physics department led the field of optical coatings for at least two decades. ;e group’s breakthroughs included methods for designing and manufacturing multilayer film stacks using ZnS, cryolite or MgF2. ;ese stacks were used as antireflection, narrow bandpass, long- and short-wavelength cuto; filters and suppressed-side-band filters. During World War II, Turner was involved in the first use of evaporated films as antireflection coatings in the United States, and he developed numerous coatings for military optical instruments.

After the war, Turner’s group at B+L was largely responsible for adapting transmission-line theory (previously developed for microwave research) to

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OSA Historical Archives Arthur Francis Turner

compute the optical behavior of films. ;e first account of this computational technique was published by P. J. Leur-gans, a former member of his laboratory, in the 1951 volume of the Journal of the Optical Society of America. ;is discovery was of great importance in the thin-film field because it made computation of the optical behavior of multilayer films possible by using recursion relations.

Turner developed the prototype design for the multiple cavity-type bandpass filter. ;e protocol includes applying optical tunneling in a bandpass filter, which he refers to as the “frustrated total reflection” filter. Turner published the first known work on the e;ects of mechanical stress in optical coatings and introduced the concept of stress compensation.

While at B+L, Turner also investigated ways to reduce the heat generated during motion picture film projection. His group came up with a successful commercial product known as the “Balcold mirror.” ;is rear-coated mirror protects film by reflecting nearly 50 percent of the heat. For this contribution, Turner and his group received the Scientific and Engineering Award from the Academy of Motion Picture Arts and Sciences in 1959.