The LD-PeCo is based on proven time-of-flight technology from SICK. An invisible double laser curtain detects persons walking through it. The direction of passage is determined, allowing unambiguous numbers to be provided. The LD-PeCo is easy to install, offers accurate counting and is maintenance-free. Unlike conventional counting technology, counting of persons with the LD-PeCo is possible at very high mounting positions. Fixed structures within the counting area can be blanked. In contrast to camera technology, the number results are not impaired by external factors, large numbers of people, or shaded areas in the field of view.