Photographic Production of Variable Light Transmission Masks

摘要

The problem is here solved of modulating a light beam as a one-dimensional function of position on a photographic film mask. This is accomplished by careful determination of the density-exposure behaviour of the film and development of a technique to control the film gamma; and a method of producing the correct film exposure to produce the desired exposure variation. While the problem here was to produce five half-sine waves it can easily be extended to include reasonably arbitrary variations of light transmission. (Author)