Terahertz measuring method and terahertz measuring device for measuring pipes

摘要

THz measuring device (3) for measuring at least one layer thickness (d) of a measuring object carried along a conveying direction (v), where the THz measuring device (3) has:a THz main sensor (30-8) for sending a THz main beam (12) along a first optical axis (A1) in a detection level (E) perpendicular to the conveyor direction (v) and for receiving THz radiation reflected along the first optical axis (A1),at least one THz additional sensor (30-i) to send a THz additional beam (14) along a second optical axis (A2) that is inclined outside the detection level (E) and/or to the detection level (E), to detect the THz additional beam reflected back along the second optical axis (A2) (14),-an evaluation and control device (16), which= a first signal luminosity (S12) of the THz main sensor (30-8), captures the main reflection peak (P1, P2, P3, P4) in the first signal luminosity (S12) and derives a distance and/or a layer thickness in the detection level (E) from the main reflection peak (P1, P2, P3, P4); and= Records a second signal luminosity (S14) of the THz additional sensor (30-i), detects additional reflection peaks (P32) in the second signal luminosity (S14) and assigns the additional reflection peaks (P32) malfunctions (32) in or on the measuring object (1),characterized by:the THz main sensor (30-8) and at least one THz additional sensor (30-i) fixed to each other;the THz main sensor (30-8) and at least one THz additional sensor (30-i) on a common measuring head (28),several additional THz sensors (30-i) together with the main THz sensor(30-8) are arranged as THz sensor array (28), with their opticalaxes (A1, A2, A3) are fixed to each other and divergent in order to detect several material ranges of the measuring object (1); andthe THz sensor array (28) forms a two-dimensional arrangement of THz sensors (30-8, 30-i).