Optical system for generating illuminated shape on moving material has delay time, switch-on duration sum less than exposure duration; material speed-dependent off time follows exposure period until next exposure period

摘要

The system has an illumination device with several light sources operated in pulsed manner by a controller to emit light to generate the shape (01) and an acquisition device for detecting light remitted from the material (03) in the form of a line camera. The switch-on duration of at least one light source is synchronized with a camera exposure period. A sum consisting of a delay time and the switch-on duration is less than the exposure duration. Following expiry of the exposure duration an off time dependent on the material speed follows until the next exposure period.