{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,3]],"date-time":"2026-06-03T15:39:04Z","timestamp":1780501144294,"version":"3.54.1"},"reference-count":31,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2020,9,14]],"date-time":"2020-09-14T00:00:00Z","timestamp":1600041600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100012166","name":"National Key Research and Development Program of China","doi-asserted-by":"publisher","award":["2019YFB2203001"],"award-info":[{"award-number":["2019YFB2203001"]}],"id":[{"id":"10.13039\/501100012166","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["61675087"],"award-info":[{"award-number":["61675087"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010211","name":"Education Department of Jilin Province","doi-asserted-by":"publisher","award":["JJKH20190118KJ"],"award-info":[{"award-number":["JJKH20190118KJ"]}],"id":[{"id":"10.13039\/501100010211","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A U-shaped double-side polished plastic optical fiber (POF) is demonstrated as a liquid refractive index (RI) sensor. The refractive index of glycerinum solutions is identified by the intensity detection on the bending and evanescent wave loss change. Heat treatment and mechanical polishing are adopted to form the symmetrical side-polished POF probe. The processing parameters are experimentally optimized on the power transmittance. The sensitivity of 1541%\/RIU (Refractive Index Unit) can be obtained with a resolution of 5.35 \u00d7 10\u22124 in the scope of 1.33\u20131.39. The favorable temperature characteristic is proved to offer stable RI sensing from 20 to 50 \u00b0C. This simple POF sensor has potentials in low-cost visible light intensity RI detection.<\/jats:p>","DOI":"10.3390\/s20185253","type":"journal-article","created":{"date-parts":[[2020,9,14]],"date-time":"2020-09-14T20:51:12Z","timestamp":1600116672000},"page":"5253","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Refractive Index Sensor Based on Double Side-Polished U-Shaped Plastic Optical Fiber"],"prefix":"10.3390","volume":"20","author":[{"given":"Shumin","family":"Wang","sequence":"first","affiliation":[{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science &amp; Engineering, Jilin University, Changchun 130012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Daming","family":"Zhang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science &amp; Engineering, Jilin University, Changchun 130012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yan","family":"Xu","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science &amp; Engineering, Jilin University, Changchun 130012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siwen","family":"Sun","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science &amp; Engineering, Jilin University, Changchun 130012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7055-1305","authenticated-orcid":false,"given":"Xiaoqiang","family":"Sun","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Integrated Optoelectronics, College of Electronic Science &amp; Engineering, Jilin University, Changchun 130012, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,9,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15","DOI":"10.1016\/j.yofte.2018.11.019","article-title":"U-bent plastic optical fiber probes as refractive index based fat sensor for milk quality monitoring","volume":"47","author":"Gowri","year":"2019","journal-title":"Opt. 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