of CaF2, and realized the value of a film material having an index of refraction intermediate between that of air and the glass. In 1938, K. Blodgett showed that the thickness of the film was of paramount importance and succeeded in reducing the reflection of monochromatic light to zero by the application of “skeletonized” films of metallic stearates. In 1938, Cartwright and Turner applied evaporated films of the metallic fluorides to glass under conditions which satisfied the correct index and thickness requirements. The metallic fluorides have unusually low indices of refraction, and a satisfactory result for photography is obtained by their approach to the ideal index. The correct thickness of the film is obtained by observing the reflection of light during the condensation of the metallic fluorides.
Although the thickness can be correct for only one wave-length of light, reflection is greatly reduced throughout the entire visible spectrum. Metallic fluoride films can be made sufficiently rugged for camera lenses and the reduced reflections from the six to ten air-glass surfaces noticeably increase the speed. The perfection of a camera lens is further increased by the absence of flare and ghost images that normally appear under adverse lighting conditions.
Dr. Cartwright projected an interesting series of “before and after” pictures, all of which demonstrated the increase in image sharpness and contrast. Perhaps the most striking of these were the photographs taken with the coronograph of Professor D. Menzel.
Annual Dinner and First Award of the Adolph Lomb Medal
On Friday evening, members of the Society and their wives were the guests of the Bausch & Lomb Optical Company at a dinner held at the Oak Hill Country Club. Nearly four hundred were in attendance. The toastmaster, Mr. C. S. Hallauer, first called on Mr. Carl Bausch, who told of the measures instituted by his company to supply the increasing need for optical glass and optical parts during this active period of preparation for national defense. The toastmaster then called on President Gibson, who introduced the charter members of the Society in turn. He also read letters from several charter members who were unable to be present because of illness.
Dr. W. B. Rayton was then asked to recount for the benefit of new members the events that led to the formation of the Optical Society of America. From his various anecdotes relating to the early days, it was abundantly evident that considerable growth and progress has been made during the quarter-century. He paid special tribute to Mr. Adolph Lomb, a charter member and treasurer of the Society until his death in 1932.
President Gibson then explained the purpose of the Board of Directors in establishing the Adolph Lomb Medal and read the conditions of award adopted at the Board meeting in October, 1939. Past President R. C. Gibbs, the chairman of the committee to nominate a candidate to receive the first award then spoke as follows:
“After canvassing a representative group of members of the Society for suggestions of suitable nominees and after a careful study of the scientific achievements of the various persons on the list thus assembled, the committee made a unanimous nomination for an award. This nomination was transmitted to the Board of Directors, which, by a unanimous vote on March 2, 1940, officially awarded the Adolph Lomb Medal for 1940 to David Lewis MacAdam.
“Born in Philadelphia, July 1, 1910, Dr. MacAdam attended the public schools in Upper Darby, Pennsylvania, and Lehigh University, receiving the B.S. degree from the latter in 1932. He then spent four years in graduate study at the Massachusetts Institute of Technology, where he received the Ph.D. degree in 1936. Since that time he has been a member of the staff of the Physics Department of the Research Laboratories at the Eastman Kodak Company in Rochester, New York.
“Dr. MacAdam’s scientific contributions have been embodied in twenty-one published papers or reports. A survey of these contributions shows five studies of major importance which may be considered as the bases for this award.
“1. Dr. MacAdam developed the theory of the maximum visual efficiency of colored materials and, on the basis of appropriate computations, prepared tables showing the maximum visual efficiency as a function of excitation purity for
