STUDIES IN CONTACT MICRORADIOGRAPHY

Recent developments in techniques for low-voltage radiography have found application for the examination and evaluation of minute details in small or thin specimens. Utilization of x-ray tubes and helium chambers with thin windows for maximum transmission of soft x rays and bare film with dark-room exposure techniques have allowed very high contrast radiographs to be produced on low-contrast materials. These conditions, coupled with very high resolution photographic emulsion detectors, have resulted in the observation of detail approximately 1 {micron} in size. Useful examination of the plates and subsequent reproductions have been made at magnifications as high as 500X. This contact system offers the advantage of evaluation of a relatively large area, as compared to the restricted field of observation of projection microradiography. Included among the subjects have been graphite-coated UC{sub 2} particles, graphite, beryllium, paper, and other organic specimens