{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,10]],"date-time":"2026-03-10T23:43:26Z","timestamp":1773186206515,"version":"3.50.1"},"reference-count":21,"publisher":"MDPI AG","issue":"22","license":[{"start":{"date-parts":[[2022,11,15]],"date-time":"2022-11-15T00:00:00Z","timestamp":1668470400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100005632","name":"National Centre for Research and Development","doi-asserted-by":"publisher","award":["DOB-SZAFIR\/02\/A\/001\/01\/2020"],"award-info":[{"award-number":["DOB-SZAFIR\/02\/A\/001\/01\/2020"]}],"id":[{"id":"10.13039\/501100005632","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We built a high-speed TDS setup with the use of electronically controlled optical sampling (ECOPS), which can measure up to 1600 terahertz pulses per second. The movement of the sample was provided by two fast-speed motorized linear stages constituting the gantry. We developed a flat-bar-based metal marker approach for the synchronization of continuous line-by-line scans. We carefully compared the performance of the terahertz reflection time-domain spectroscopy (TDS) scanner operating in a slow point-by-point and a one-hundred-times faster line-by-line imaging scheme. We analyzed images obtained for both schemes for a uniform metallic breadboard with holes, as well as a glass composite sample with defects. Although the measurement time was reduced by 100 times in terms of the line-by-line scheme, the overall performance in both schemes was almost identical in terms of the defects\u2019 sizes, shapes and locations. The results proved that the proposed ECOPS TDS system can provide uniform and extremely fast scanning without any deterioration in image quality.<\/jats:p>","DOI":"10.3390\/s22228813","type":"journal-article","created":{"date-parts":[[2022,11,15]],"date-time":"2022-11-15T02:36:40Z","timestamp":1668479800000},"page":"8813","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":17,"title":["Fast THz-TDS Reflection Imaging with ECOPS\u2014Point-by-Point versus Line-by-Line Scanning"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1931-876X","authenticated-orcid":false,"given":"Norbert","family":"Pa\u0142ka","sequence":"first","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4787-7868","authenticated-orcid":false,"given":"Marcin","family":"Maciejewski","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3645-9337","authenticated-orcid":false,"given":"Kamil","family":"Kami\u0144ski","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3376-6427","authenticated-orcid":false,"given":"Marek","family":"Piszczek","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6603-7605","authenticated-orcid":false,"given":"Przemys\u0142aw","family":"Zagrajek","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"El\u017cbieta","family":"Czerwi\u0144ska","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3053-8333","authenticated-orcid":false,"given":"Micha\u0142","family":"Walczakowski","sequence":"additional","affiliation":[{"name":"Institute of Optoelectronics, Military University of Technology, 2 Kaliski Street, 00-908 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Krzysztof","family":"Dragan","sequence":"additional","affiliation":[{"name":"Air Force Institute of Technology, 6 Ksi\u0105\u017ce Boles\u0142aw Street, 01-494 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7884-0582","authenticated-orcid":false,"given":"Piotr","family":"Synaszko","sequence":"additional","affiliation":[{"name":"Air Force Institute of Technology, 6 Ksi\u0105\u017ce Boles\u0142aw Street, 01-494 Warsaw, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4040-2197","authenticated-orcid":false,"given":"Waldemar","family":"\u015awiderski","sequence":"additional","affiliation":[{"name":"Military Institute of Armament Technology, Prymasa Stefana Wyszy\u0144skiego 7 Street, 05-220 Zielonka, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"231101","DOI":"10.1063\/1.5047659","article-title":"Tutorial: An Introduction to Terahertz Time Domain Spectroscopy (THz-TDS)","volume":"124","author":"Neu","year":"2018","journal-title":"J. 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