Inspection of elongated material

摘要: Apparatus and method are described for inspecting elongated material such as strands, sheets, bundles or webs the presence of surface irregularities, count irregularities within a given length angle in case crimped fiber. A light source is used to form areas shadowed material. television camera produces video signal electronically analyzed with respect number alternating dark length, relative widths areas, from which information can be obtained confirm frequency, angle. filter disclosed removing relatively low frequency signals caused by unintentional shadowing useful so that accuracy apparatus improved.