Abstract: A device is disclosed which detects and evaluates electromagnetic radiation from an area or region. The device includes two measuring chains, and a control and evaluation unit. Each measuring chain has a head forming a boundary surface for the area and is provided with a transmitter and a receiver. In order to test the device, a test signal is emitted via the transmitter of one measuring chain and is reflected on the boundary surface. The reflected portion is received by the receiver of the same measuring chain and is transmitted to the control and evaluation unit. The portion transmitted is received via the boundary surface of the receiver of the opposite measuring chain and is transmitted to the control and evaluation unit. The comparison of the two signals provides statements relating to the contamination of the boundary surfaces, the state of the area and the functioning of the measuring chains.

Abstract: A device which is intended to detect and evaluate electromagnetic radiation from an area (2) consists substantially of two measuring chains, which are combined in constructional units (5′,6′), and of a control and evaluation unit (7), wherein the measuring chains are equipped with diametrically opposed measuring heads, whose aperture angles (10) are equal in dimension. Each measuring head forms a boundary surface for the area (2) to be monitored and is provided with a transmitter and a receiver, wherein the boundary surface is intended for coupling radiation into and out of the area (2) respectively. In order to test the functional reliability of the device, a test signal is emitted in a first test procedure via the transmitter of one measuring chain and is reflected in part on the said boundary surface and issues out in part into the area (2). The reflected portion is coupled in by the receiver of the same measuring chain and is transmitted via a line (8) to the control and evaluation unit (7).

Abstract: During testing of a panel-like workpiece by means of ultrasonic penetration and at least one inspection channel comprising an ultrasonic transmitter and an ultrasonic receiver on opposite-lying sides of the workpiece, diverse test signals and test information are accumulated at the ultrasonic receiver. Each ultrasonic receiver is connected to an evaluation system, in which the test signals and the test information are combined, evaluated and reduced to a single piece of result-information which describes the tested workpiece. If at least two inspection channels are provided, it can also be provided that a reduction to a single piece of result-information is performed in each case for each ultrasonic receiver.