{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,12]],"date-time":"2026-03-12T01:06:25Z","timestamp":1773277585528,"version":"3.50.1"},"reference-count":40,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2020,6,12]],"date-time":"2020-06-12T00:00:00Z","timestamp":1591920000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100004955","name":"\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft","doi-asserted-by":"publisher","award":["871974"],"award-info":[{"award-number":["871974"]}],"id":[{"id":"10.13039\/501100004955","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100004955","name":"\u00d6sterreichische Forschungsf\u00f6rderungsgesellschaft","doi-asserted-by":"publisher","award":["843546"],"award-info":[{"award-number":["843546"]}],"id":[{"id":"10.13039\/501100004955","id-type":"DOI","asserted-by":"publisher"}]},{"name":"Upper Austria","award":["Innovative Upper Austria 2020"],"award-info":[{"award-number":["Innovative Upper Austria 2020"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Terahertz time-domain spectroscopy is a useful technique to characterize layered samples and thin films. It gives access to their optical properties and thickness. Such measurements are done in transmission, which requires access to the sample from opposite sides. In reality this is not always possible. In such cases, reflection measurements are the only option, but they are more difficult to implement. Here we propose a method to characterize films in reflection geometry using a polarimetric approach based on the identification of Brewster angle and modeling of the measured signal to extract the refractive index and thickness of the sample. The technique is demonstrated experimentally on an unsupported single layer thin film sample. The extracted optical properties and thickness were in good agreement with established transmission terahertz spectroscopy measurements. The new method has the potential to cover a wide range of applications, both for research and industrial purposes.<\/jats:p>","DOI":"10.3390\/s20123352","type":"journal-article","created":{"date-parts":[[2020,6,15]],"date-time":"2020-06-15T05:56:27Z","timestamp":1592200587000},"page":"3352","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":6,"title":["Terahertz Time-Domain Polarimetry in Reflection for Film Characterization"],"prefix":"10.3390","volume":"20","author":[{"given":"Sandrine","family":"van Frank","sequence":"first","affiliation":[{"name":"Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Stra\u00dfe 69, 4040 Linz, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7339-0140","authenticated-orcid":false,"given":"Elisabeth","family":"Leiss-Holzinger","sequence":"additional","affiliation":[{"name":"Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Stra\u00dfe 69, 4040 Linz, Austria"}]},{"given":"Michael","family":"Pfleger","sequence":"additional","affiliation":[{"name":"Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Stra\u00dfe 69, 4040 Linz, Austria"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7354-7651","authenticated-orcid":false,"given":"Christian","family":"Rankl","sequence":"additional","affiliation":[{"name":"Research Center for Non-Destructive Testing GmbH (RECENDT), Altenberger Stra\u00dfe 69, 4040 Linz, Austria"}]}],"member":"1968","published-online":{"date-parts":[[2020,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"23","DOI":"10.1016\/0020-0891(86)90043-6","article-title":"A novel technique for measuring far-infrared absorption and dispersion","volume":"26","author":"Cheung","year":"1986","journal-title":"Infrared Phys."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"124","DOI":"10.1002\/lpor.201000011","article-title":"Terahertz spectroscopy and imaging\u2014Modern techniques and applications","volume":"5","author":"Jepsen","year":"2011","journal-title":"Laser Photon. 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