Optical sensor for detecting presence of object or obstruction uses light beam traveling along concave surface with multiple reflections at grazing angle of incidence

摘要

The detector system (1) has a transmitter-receiver pair (2) with a lamp (4) producing a light beam (3) which has multiple reflections from a concave reflective surface (10) of a machine part (9). An object (11) placed on this surface interrupts the light beam. The beam receiver (6) is connected to an evaluation circuit (7) and a switching circuit (8).