An automatic nuclear emulsion scanner with moving microscope

Abstract

An automatic scanning device has been built for counting tracks in nuclear emulsion plates exposed in a magnetic spectrograph. It differs from those described earlier in using a moving microscope to project a very small area of the plate onto a fixed system of slits. This ensures the uniformity of illumination and stability of resolution along the whole scanned strip and eliminates the effect of photocathode non-uniformity too. The device processes 1.3 mm 2 of the plate scanned strip and eliminates the effect of photocathode non-uniformity too. The device processes 1.3 mm 2 of the plate per second, with a resolution of 3 ωm and an accuracy better than 5% for the densities up to 400–500 tracks per mm 2 for good quality plates. The strip length is 20 mm and may easily be made larger.