{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T03:33:09Z","timestamp":1760239989261,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2019,2,16]],"date-time":"2019-02-16T00:00:00Z","timestamp":1550275200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000038","name":"Natural Sciences and Engineering Research Council of Canada","doi-asserted-by":"publisher","award":["RGPIN-2015-06515"],"award-info":[{"award-number":["RGPIN-2015-06515"]}],"id":[{"id":"10.13039\/501100000038","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000196","name":"Canada Foundation for Innovation","doi-asserted-by":"publisher","award":["25251"],"award-info":[{"award-number":["25251"]}],"id":[{"id":"10.13039\/501100000196","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present a bi-conical optical directional coupler composed of solid and hollow core fibers. Through an evanescent wave coupling mechanism, the detection of liquid refractive index and its temperature are demonstrated. The experimental results illustrated that the sensor offers a sensitivity of     4.03 \u00b1 0.50     volts per refractive index units (V\/RIU) for refractive indices ranging from     1.331 \u00b1 0.003     to     1.403 \u00b1 0.003     with a resolution of     3.5 \u00d7  10  \u2212 3       refractive index units (RIU).<\/jats:p>","DOI":"10.3390\/s19040806","type":"journal-article","created":{"date-parts":[[2019,2,17]],"date-time":"2019-02-17T22:11:50Z","timestamp":1550441510000},"page":"806","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Hollow Fiber Coupler Sensor"],"prefix":"10.3390","volume":"19","author":[{"given":"Nithin","family":"Kuruba","sequence":"first","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Victoria, Victoria, BC V8P 5C2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tao","family":"Lu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Computer Engineering, University of Victoria, Victoria, BC V8P 5C2, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,2,16]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"291","DOI":"10.1006\/ofte.1996.0036","article-title":"A review of recent developments in fiber optic sensor technology","volume":"2","author":"Kersey","year":"1996","journal-title":"Opt. 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