Tunnel light source using high-power LED particles, through the semi-cylindrical arc surface diffuse reflection, forming a uniform strip of light, can choose the middle hole or slot to cooperate with the surface array camera and line array camera use, the use of air cooling design, fully ensure the service life of the product. The application range is smooth film detection, large area glass defect detection, PCB/ copper foil detection, cigarette packaging detection, printed matter surface detection.