The apparatus described is designed to measure relative illumination of finite conjugate lenses with comparable accuracy and reliability than existing methods and provides a graphical output with less time expended for data acquisition. An opto-mechanical scanning system is utilized for transmitting light pulses from known image field positions to a photomultiplier tube. The light pulses are transmitted to the phototube via an optical system consisting of an array of lucite rods (light pipes) positioned in the image plane of the lens under test. The rods terminate at a cylindrical housing which contains a rotating lens prism assembly which scans the end of each lucite rod in sequence and relays the illumination values to the photomultiplier. The output current of the tube is displayed on a cathode ray tube oscilloscope and photographed. Data obtained with this apparatus were compared to data obtained using photographic photometry. Results indicate that the apparatus is very repeatable and that data aquisition time is significantly reduced.
Library of Congress Subject Headings
Photographic optics; Photographic lenses
Department, Program, or Center
School of Photographic Arts and Sciences (CIAS)
Fedele, Claude and Neumann, Leo, "An experimental apparatus for measuring the relative illumination of finite conjugate lenses" (1965). Thesis. Rochester Institute of Technology. Accessed from
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