INSPECTION AND/OR SHEET OBSERVATION DEVICE, USE OF AN ASSEMBLY AS BACKGROUND SCREEN OR TRANSMITTED LIGHT TRANSMITTER IN THE INSPECTION AND/OR SHEET OBSERVATION DEVICE AND METHOD FOR OPERATING THE INSPECTION AND/OR SHEET OBSERVATION DEVICE

摘要

An apparatus for inspecting or observing a material web, a process of inspecting the material web and a method for operating the apparatus for inspecting or observing the material web are provided. The apparatus has a guiding device through which the material web is guided and a camera including a field of view and configured to record an image of the front side within the field of view. An incident light transmitter is configured to illuminate the front side with incident light, and a background panel is arranged on the rear side of the material web within the field of view. The background panel includes a diffuser plate, a light guide plate, a reflecting surface, and a light source configured to couple light into the light guide plate which is configured to uncouple the light to illuminate the rear side of the material web with transmitted light.