Wide Film Detect System

Wide film detect system, studied in the paper, is one kind of industry vision system. Wide film is useful recording medium, such as photograph, press and medicine. In the course of production, one main problem is the film is scathed by these transmit rolls. It will affect later imaging effect directly. How to assure its quality is an important task. Now, the film detection is a manual work and only some selected samples could be detected. The detection will be done after all production courses are finished. So, it is a difficult task to assure the film quality.In the paper, a wide film detect system was studies. The film detection task could be real-time operated when the wide film detect system is assembled with production line. The film detect system, like other industry vision system, is composed of optical system, CCD sensor, image frame grabber, light source and computer. The detection principle is based on image processing method. One point need to be shown, that is a suit light source is very important to the whole detection system. The light source shouldn't damage the film and it must have enough power to assure the CCD sensor could detect. Infrared LED, which main wavelength is 940nm, was selected as source light. The detection speed is up to 90 m/min, detection width is 1300mm and detection resolution could up to 0.5mm at the operation direction and 0.05mm at the film width direction.