The Research and Development Department at Peerless Control Systems Limited, at Milton Keynes is developing an Automatic Visual Inspection System for inspecting internal surfaces. The system will automatically inspect and measure useful parameters (ie. longitudinal distances, internal hole diameters, screw threads, pitches, surface, finish quality) and detect defects of types which may be due to machining marks, material defects, and inclusions due to environmental contamination Leg. rust, stains, smears, etc.). The system consists of special customized optics and a dedicated real time computer system with its integral image processing and display system. The final production version will be a customized, dedicated micro processor based system. The customized optics implement optical sensing of imaging data of internal surfaces. The optics are linked to a specialised image converter which is interfaced to a computer system. The software developed at P.C.S. provides the image analysis of the internal surface, thus providing auto-inspection variables, which can be applied to numerous industrial and scientific inspection tasks. The machine will be capable of being used on the production line with an inspection time of a few seconds. Automatic mechanical handling can be incorporated within the above system to save routine handling tasks. This Automatic Inspection System reduces internal surface inspection time, maintains consistent higher quality inspection specifications resulting in a cost time saving, economic utilization of raw materials and increased output.