Light guide bar and strip for materials - scanning

摘要

Magnesium oxide power is placed in a groove on the outside of a light guide bar to form a translucent or reflecting strip and this reflect incident beams off or back into the bar through a diffusion layer for repeated reflection and final emission onto the material web or strip being scanned. The strips should be wide enough to fill the entire diameter of the bar when viewed through this bar forming a cylindrical lens. The strip can be notched, one face flat and the other domed, to achieve directional scanning.