Visual defect detection is a non-contact, non-destructive automatic detection technology. It is an effective means to realize equipment automation, intelligence and precision control. It has the characteristics of safety, reliability, wide spectral response range, long-term working in harsh environments and production efficiency. High outstanding advantages. Visual defect detection technology performs visual dimensional measurement, flaw detection, defect detection, and packaging inspection. It is oriented to the composite materials industry, fiberglass industry, textile industry, and manufacturing enterprises. It can detect scratches, stains, holes on the appearance of metal; and defects on the appearance of paper. Different colors or dents as well as glass; non-metallic appearance inclusions, cracks, dirt, etc.