Method and device for testing running transparent webs

摘要

In the testing of running transparent webs for ruptures extending in the web, a light beam is guided essentially transversely to the running direction of the transparent web to be tested at a constant angle of less than 90 degrees, referred to the perpendicular to the transparent material web, the light transmitted is detected under the web by a photoelectric converter and fed to a computer in which the evaluation is carried out. The angle of the light beam lies between 10 and 80 degrees, referred to the perpendicular, the transmitter and the receiver are each respectively mounted on a slide, the slides being moved at the same speed parallel to each other over and under the transparent material web transverse to its running direction. IMAGE