Microscopic circular shape size distribution measurement - using optical appts. comparing shape with standard ring and electronically counting results

摘要

An apparatus for determining the size distribution of microscopic circular shapes, for example in textile, chemical or medical production, is presented. The particle is illuminated by a light beam which is then split and displayed on two screens, each of which has a transparent ring-shaped window. The screens are movable and are arranged so that the image falls concentrically with respect to the ring-shaped window. The rings are of different diameter, so that, if the smaller ring is totally covered by the image whilst the larger ring is not covered, the particle size is a member of the set specified by that ring pair.