High Speed Motion Pictures of the Vocal Cords
W. Herriott, David W. Farnsworth · The Journal of the Acoustical Society of America · 1938
Bell Telephone Laboratories has for several years made use of high speed motion picture photography as a visual aid in the study of problems associated with the design, manufacture and performance of telephone apparatus. This presentation is concerned with its application to problems relating to the functioning of the vocal cords in speech production. Vocal cord pictures taken at several different camera speeds up to 4000 frames per second are shown. These pictures, projected at a rate of sixteen or twenty-four frames per second, permit detailed observation of the motion of the cords vibrating at voice frequencies. Adequate illumination was secured by directly imaging a tungsten light source on the vocal cords. Harmful heat and ultraviolet radiation were absorbed by a liquid filter.