Abstract
A technical description is given of a system that has been developed and used for a number of years in work reported on the assessment of silver halide and other light sensitive photographic materials. The instrument uses coherent light both for generating test patterns and for measuring the properties of the exposed samples. The parameters that may be evaluated in this instrument are transmittance as a function of exposure, diffraction efficiency of gratings, modulation transfer function (MTF), and scattered flux spectrum. The heart of the system is an arrangement that generators sinusoidal irradiance distribution from laser two-beam interference over a continuous spatial frequency range from about 3 to 3000 cycles/mm. Accessory units adapt the system to various evaluation tasks. One configuration is the multiple-sine-slit microdensitometer (MSSM), which measures transmittance modulation with constant and high accuracy up to 1500 cycles/mm.