Patent ID: 7531787
Filing Date: 2009-05-12
Classification: G01V

Abstract:
1. A monitoring device for a space that is to be monitored for entry of at least one body via an access area comprising: a plurality of light field regions comprising a plurality of light fields, each of the light fields including: at least one emitting element which introduces luminous radiation into the access area; and at least one receiving element which receives the luminous radiation, wherein at least one light guide is associated with the emitting element, said light guide emitting the luminous radiation into the access area as one of the plurality of light fields transversely to a longitudinal direction of the at least one light guide; and wherein at a receiving end at least one light guide is provided as a detecting element for detecting the one of the plurality of light fields transversely to the longitudinal direction of the at least one light guide at the receiving end and as transmitting means for transmitting the light out of the light field to the receiving element, wherein at least two light field regions arranged at an angle to one another cross within the access area, and wherein each light field region comprises at least two light fields which are arranged one behind the other in a direction of motion of the body.