{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T19:55:26Z","timestamp":1777406126202,"version":"3.51.4"},"reference-count":39,"publisher":"MDPI AG","issue":"15","license":[{"start":{"date-parts":[[2022,8,1]],"date-time":"2022-08-01T00:00:00Z","timestamp":1659312000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science, ICT and future Planning","award":["NRF-2019R1A2C1084933"],"award-info":[{"award-number":["NRF-2019R1A2C1084933"]}]},{"name":"Ministry of Science, ICT and future Planning","award":["NRF-2020R1A6A1A03047771"],"award-info":[{"award-number":["NRF-2020R1A6A1A03047771"]}]},{"name":"Ministry of Science, ICT and future Planning","award":["P0008458"],"award-info":[{"award-number":["P0008458"]}]},{"name":"Korea Government (MOTIE)","award":["NRF-2019R1A2C1084933"],"award-info":[{"award-number":["NRF-2019R1A2C1084933"]}]},{"name":"Korea Government (MOTIE)","award":["NRF-2020R1A6A1A03047771"],"award-info":[{"award-number":["NRF-2020R1A6A1A03047771"]}]},{"name":"Korea Government (MOTIE)","award":["P0008458"],"award-info":[{"award-number":["P0008458"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Cholesteric liquid crystals (CLCs) can be applied to various physical and chemical sensors because their alignment structures are changed by external stimuli. Here, we propose a CLC device fabricated by vertically forming the helical axis of the CLC between the cross-sections of two optical fiber ferrules. An optical fiber temperature sensor was successfully implemented using the proposed optical fiber ferrule-based CLC device. A wideband wavelength-swept laser with a center wavelength of 1073 nm and scanning range of 220 nm was used as a light source to measure the variations in the reflection spectrum band according to the temperature change in the CLC cell. The wavelength variation of the reflection spectrum band according to the temperature applied to the CLC cell was reversible and changed linearly with a change in the temperature, and the long-wavelength edge variation rate according to the temperature change was \u22125.0 nm\/\u00b0C. Additionally, as the temperature applied to the CLC cell increased, the reflection spectrum bandwidth gradually decreased; the reflection spectrum bandwidth varied at a rate of \u22121.89 nm\/\u00b0C. The variations in the refractive indices with temperature were calculated from the band wavelengths of the reflection spectrum. The pitch at each temperature was calculated based on the refractive indices and it gradually decreased as the temperature increased.<\/jats:p>","DOI":"10.3390\/s22155752","type":"journal-article","created":{"date-parts":[[2022,8,1]],"date-time":"2022-08-01T23:49:27Z","timestamp":1659397767000},"page":"5752","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["Fiber-Optic Temperature Sensor Using Cholesteric Liquid Crystals on the Optical Fiber Ferrules"],"prefix":"10.3390","volume":"22","author":[{"given":"Soyeon","family":"Ahn","sequence":"first","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"given":"Gi Hyen","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"given":"Jun-Yong","family":"Lee","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6773-2738","authenticated-orcid":false,"given":"Youngseo","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"given":"Min Su","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9301-0694","authenticated-orcid":false,"given":"Srinivas","family":"Pagidi","sequence":"additional","affiliation":[{"name":"Institute of Quantum Systems (IQS), Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"given":"Byeong Kwon","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"given":"Ji Su","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"given":"Jong-Hyun","family":"Kim","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"},{"name":"Institute of Quantum Systems (IQS), Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9944-8993","authenticated-orcid":false,"given":"Min Yong","family":"Jeon","sequence":"additional","affiliation":[{"name":"Department of Physics, College of Natural Sciences, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"},{"name":"Institute of Quantum Systems (IQS), Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Korea"}]}],"member":"1968","published-online":{"date-parts":[[2022,8,1]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"072009","DOI":"10.1117\/1.OE.58.7.072009","article-title":"Multiparameter fiber-optic sensors: A review","volume":"58","author":"Pevec","year":"2019","journal-title":"Opt. 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