US 12,146,733 B2
Measuring device and method of operating a measuring device
Rüdiger Mästle, Böblingen (DE); and Lars-Christian Anklamm, Berlin (DE)
Assigned to HELMUT FISCHER GMBH INSTITUT FÜR ELEKTRONIK UND MESSTECHNIK, Sindelfingen (DE)
Appl. No. 17/426,597
Filed by HELMUT FISCHER GMBH INSTITUT FÜR ELEKTRONIK UND MESSTECHNIK, Sindelfingen (DE)
PCT Filed May 25, 2020, PCT No. PCT/EP2020/064440
§ 371(c)(1), (2) Date Jul. 28, 2021,
PCT Pub. No. WO2020/239694, PCT Pub. Date Dec. 3, 2020.
Claims priority of application No. 19176500 (EP), filed on May 24, 2019.
Prior Publication US 2022/0091028 A1, Mar. 24, 2022
Int. Cl. G01B 11/06 (2006.01); G01B 11/02 (2006.01); G01B 21/04 (2006.01); G01N 21/3581 (2014.01); G01N 21/3586 (2014.01); G01B 11/26 (2006.01)
CPC G01B 11/0625 (2013.01) [G01B 11/026 (2013.01); G01B 21/045 (2013.01); G01N 21/3581 (2013.01); G01N 21/3586 (2013.01); G01B 11/0616 (2013.01); G01B 11/26 (2013.01)] 18 Claims
OG exemplary drawing
 
1. A method of operating a measuring device comprising a Terahertz, THz, transmitter configured to emit a THz signal (TS) to a reference object to be measured and a THz receiver configured to receive a reflected portion (TSR) of said THz signal (TS) that has been reflected by said reference object, wherein said THz transmitter and said THz receiver are arranged in a measuring head of said measuring device, said method comprising:
A) varying a distance (d) between said measuring head and said reference object to be measured, having a known geometry, emitting, by said THz transmitter, said THz signal (TS) to said reference object to be measured, receiving said reflected portion (TSR) of said THz signal (TS), and determining a first parameter characterizing a detected signal proportional and/or related to said received reflected portion (TSR) of said THz signal (TS), further including:
for a plurality of distance values (dv) of said distance (d) between said measuring head and said reference object to be measured, wherein the plurality of distance values (dv) are within a predetermined first range: determining and storing in at least one database said plurality of distance values (dv), determining and storing in the at least one database first reference measurement information (rmi1) characterizing a received reflected portion (TSR) of said THz signal (TS) associated with said plurality of distance values (dv); and
B) varying a relative angular position of said measuring head with respect to said reference object to be measured, emitting, by said THz transmitter, said THz signal (TS) to said reference object to be measured, receiving said reflected portion (TSR) of said THz signal (TS), determining a second parameter characterizing a detected signal proportional or related to said received reflected portion (TSR) of said THz signal (TS), further including:
for a plurality of relative angular position values of a relative angular position between said measuring head and said reference object to be measured, wherein said plurality of relative angular position values (apv) are of a predetermined second range: determining and storing in the at least one database said plurality of relative angular position values (apv), determining and storing in the at least one database second reference measurement information (rmi2) characterizing a received reflected portion (TSR) of said THz signal (TS) associated with said plurality of relative angular position values (apv);
performing measurements of a sample object to be measured that is different from the reference object and that is not positioned at an optimum measuring distance (omd) and/or an optimum measuring angle (oma) and obtaining measurement results (mr); and
modifying said measurement results (mr) of the sample object to be measured by using said plurality of distance values and said first reference measurement information (rmi1) stored in the at least one database, and said plurality of relative angular position values (apv) and said second reference measurement information (rmi2) stored in the at least one database.