Abstract: A method is provided for detecting objects located in or entering into an area to be monitored with a device including a transmitter, a receiver and an evaluation unit. A transmitted beam emitted by the transmitter transversely to the radiation direction of the transmitted beam is guided inside the area. For different orientations of the transmitted beam, the distances of the objects from the device are detected and these measured position values are stored in the evaluation unit. For detecting objects of a particular shape the measured position values for the respective object are compared with set values, which are calculated in the evaluation unit from the shape of the object when in a predetermined position in the area to be monitored. An object having a defined shape is considered to have been recognized when a minimum number N of the measured position values falls around the set values within at least one tolerance band T.