US 11,988,499 B2
THz measuring device and THz measuring method for determining a layer thickness or a distance of a measurement object
Roland Böhm, Altenberge (DE)
Assigned to CiTEX Holding GmbH, Melle (DE)
Appl. No. 17/440,459
Filed by CiTEX Holding GmbH, Melle (DE)
PCT Filed Mar. 13, 2020, PCT No. PCT/DE2020/100188
§ 371(c)(1), (2) Date Sep. 17, 2021,
PCT Pub. No. WO2020/200360, PCT Pub. Date Oct. 8, 2020.
Claims priority of application No. 10 2019 108 299.4 (DE), filed on Mar. 29, 2019.
Prior Publication US 2022/0146251 A1, May 12, 2022
Int. Cl. G01B 11/06 (2006.01); G01N 21/3563 (2014.01); G01N 21/3581 (2014.01)
CPC G01B 11/0691 (2013.01) [G01B 11/06 (2013.01); G01N 21/3563 (2013.01); G01N 21/3581 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A THz measuring device for measuring a layer thickness of a wall of a measurement object and/or of a distance between boundary surfaces of a measurement object, the THz measuring device comprising
a Terahertz transmitter for irradiating Terahertz radiation along an optical axis onto the measurement object and a Terahertz receiver for receiving Terahertz radiation reflected from the measurement object,
a controller configured to determine the layer thickness of the wall of the measurement object and/or a distance between boundary surfaces of the measurement object from a time-of-flight difference of the Terahertz radiation reflected on a first boundary surface of the wall of the measurement object and the Terahertz radiation reflected on a second boundary surface of the wall,
where a reflector is arranged in a beam path of the Terahertz transmitter and the Terahertz receiver, where a surface of the reflector is configured to deflect the irradiated Terahertz radiation and/or the Terahertz radiation reflected on the respective boundary surface to adjust the optical axis of the Terahertz transmitter and the Terahertz receiver,
wherein the reflector is designed to be deformable to modify a beam cross-section of the irradiated Terahertz radiation in a focusing plane lying downstream from the reflector in the beam direction of the irradiated Terahertz radiation, the focusing plane being adjustable by deforming the reflector.