A microphotometer of the type described by Vincent and Sawyer has been altered optically and electrically to eliminate certain objectionable features. Scattered light, dependence of the plate projection lens upon the aperture of the plate illumination system, photo-cell fatigue, relatively short life of the projection lamp, and the need for a constant voltage power supply have been eliminated. Plate calibration curves obtained with the altered instrument on wide bands and narrow lines are essentially identical.
H. H. GROSSMAN, E. W. PETERSON, J. L. SAUNDERSON, and V. J. CALDECOURT, "Optical and Electrical Alterations to a Michigan Microphotometer," J. Opt. Soc. Am. 39, 261-263 (1949)