{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,25]],"date-time":"2025-12-25T01:48:22Z","timestamp":1766627302607,"version":"build-2065373602"},"reference-count":34,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2023,1,8]],"date-time":"2023-01-08T00:00:00Z","timestamp":1673136000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["11727812","61927813","2018YFB0504400"],"award-info":[{"award-number":["11727812","61927813","2018YFB0504400"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["11727812","61927813","2018YFB0504400"],"award-info":[{"award-number":["11727812","61927813","2018YFB0504400"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We propose and implement a terahertz time-of-flight ranging system based on adaptive clock asynchronous optical sampling, where the timing jitter is corrected in real time to recover the depth information in the acquired interferograms after compensating for laser instabilities using electronic signal processing. Consequently, the involved measurement uncertainties caused by the timing jitter during the terahertz sampling process and the noise intensity of the terahertz electric field have been reduced by the utilization of the adaptive clock. The achieved uncertainty range is about 2.5 \u03bcm at a 5 cm distance after averaging the acquisition time of 1876 ms 5000 times, showing a significant improvement compared with the asynchronous optical sampling using a constant clock. The implemented terahertz ranging system only uses free-running mode-locked lasers without any phase-locked electronics, and this favors simple and robust operations for subsequent applications that extend beyond the laboratory conditions.<\/jats:p>","DOI":"10.3390\/s23020715","type":"journal-article","created":{"date-parts":[[2023,1,9]],"date-time":"2023-01-09T07:05:09Z","timestamp":1673247909000},"page":"715","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Terahertz Time-of-Flight Ranging with Adaptive Clock Asynchronous Optical Sampling"],"prefix":"10.3390","volume":"23","author":[{"given":"Min","family":"Li","sequence":"first","affiliation":[{"name":"Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"}]},{"given":"Zheng","family":"Liu","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"}]},{"given":"Yu","family":"Xia","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"}]},{"given":"Mingyang","family":"He","sequence":"additional","affiliation":[{"name":"Jinan Institute of Quantum Technology, Jinan 250101, China"}]},{"given":"Kangwen","family":"Yang","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"}]},{"given":"Shuai","family":"Yuan","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"}]},{"given":"Ming","family":"Yan","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1899-7924","authenticated-orcid":false,"given":"Kun","family":"Huang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9025-9643","authenticated-orcid":false,"given":"Heping","family":"Zeng","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Modern Optical System, Engineering Research Center of Optical Instrument and System, Ministry of Education, School of Optical-Electrical and Computer Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China"},{"name":"Jinan Institute of Quantum Technology, Jinan 250101, China"},{"name":"State Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China"},{"name":"Chongqing Key Laboratory of Precision Optics, Chongqing Institute of East China Normal University, Chongqing 401121, China"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"292","DOI":"10.1016\/j.optlaseng.2008.03.013","article-title":"Optical measurement techniques for mobile and large-scale dimensional metrology","volume":"47","author":"Cuypers","year":"2009","journal-title":"Opt. 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