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 (MIT) and a Ph.D. in physics from the University of Berlin, Germany, in 1935. Turner continued his studies in Berlin with Peter Pringsheim and Marianus Czerny. It is said that Czerny was the last doctoral student of the celebrated 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. This work went largely forgotten until the Ebert system was rediscovered in 1952. Several years passed before anyone realized that the Czerny-Turner system offers 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.
In 1935, Turner accepted a teaching position at MIT, where he was reunited with Cartwright. The 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. The group’s breakthroughs included methods for designing and manufacturing multilayer film stacks using ZnS, cryolite or MgF2. These stacks were used as antireflection, narrow bandpass, long- and short-wavelength cutoff 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 compute the optical behavior of films. The first account of this computational technique was published by P. J. Leurgans, a former member of his laboratory, in the 1951 volume of the Journal of the Optical Society of America. This 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. The 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 effects 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.” This 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.
His research efforts in the 1960s included designing laser coatings with a broad region of high reflectance and pioneering research on laser damage in optical interference coatings. Turner helped to initiate many of the types of interference filters in use today. He coauthored a paper with Peter Berning that laid the theoretical groundwork for the “induced transmission” bandpass filter, which is finding ever-increasing applications in medical and analytical instruments.
He was a consultant to the Colorado State University physics department and to the University of Arizona Optical Sciences Center (now the College of Optical Sciences) for several years. He also served as a visiting professor at Arizona. In 1970, Dean McKeriney, his third predoctoral student, became the first student to receive a Ph.D. from the Optical Sciences Center. His earlier Ph.D. students were F. Dow Smith (Rochester, 1951) and Leei Chang (Colorado State, 1964). (Smith later served as president and treasurer of OSA.) Turner retired from B+L in 1971, but he did not retire from optics. He accepted a professorship at the Optical Sciences Center, a position he held for 25 years.
Turner was an OSA Fellow and a member of the Rochester section, for which he served as both secretary and president. Turner was OSA’s 1968 President and the first chairman of the technical group on thin films and interferometry. He served on committees too numerous to mention. In 1971, Turner was selected as the OSA Frederic Ives medalist. The selection committee compiled a detailed list of his publications and technical achievements, from which this article has drawn many details.
In addition to his publications, Turner held 24 patents in films and optics. He was a cheerful, dapper person, almost always wearing a bow tie and often puffing on a cigar. He very much enjoyed his research and he communicated that enjoyment to his colleagues and students. Turner died in Tucson, Ariz., on 3 April 1996 at the age of 90.
John N. Howard is the founding editor of Applied Optics and retired chief scientist of the Air Force Geophysics Laboratory.