Patent attributes
Laser scanner monitors region in front of an opening. Monitoring region is delimited by a frame, in front of which an edge region is located. Propagation time sensing means determines position of an object in the monitoring region by a propagation time measurement of laser pulse, an evaluation unit being provided, by means of which first object information is produced, whether an object was sensed by the propagation time measurement. An intensity sensing means evaluating received laser pulse with respect to the intensity thereof and the sensed intensity is compared with a reference intensity stored in a memory unit. Second object information being provided in the event of deviation beyond a certain threshold value, whether an object is located in the hazard edge region on the basis of the intensity deviation. A “safety signal” generated by the evaluation unit if first or second object information is positive.
