{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,1]],"date-time":"2026-05-01T16:27:45Z","timestamp":1777652865639,"version":"3.51.4"},"reference-count":45,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2020,7,5]],"date-time":"2020-07-05T00:00:00Z","timestamp":1593907200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we propose and experimentally demonstrate a simple technique to enhance the curvature sensitivity of a bending fiber optic sensor based on anti-resonant reflecting optical waveguide (ARROW) guidance. The sensing structure is assembled by splicing a segment of capillary hollow-core fiber (CHCF) between two single-mode fibers (SMF), and the device is set on a steel sheet for measuring different curvatures. Without any surface treatment, the ARROW sensor exhibits a curvature sensitivity of 1.6 dB\/m\u22121 in a curvature range from 0 to 2.14 m\u22121. By carefully coating half of the CHCF length with polydimethylsiloxane (PDMS), the curvature sensitivity of the ARROW sensor is enhanced to \u22125.62 dB\/m\u22121, as well as an increment in the curvature range (from 0 to 2.68 m\u22121). Moreover, the covered device exhibits a low-temperature sensitivity (0.038 dB\/\u00b0C), meaning that temperature fluctuations do not compromise the bending fiber optic sensor operation. The ARROW sensor fabricated with this technique has high sensitivity and a wide range for curvature measurements, with the advantage that the technique is cost-effective and easy to implement. All these features make this technique appealing for real sensing applications, such as structural health monitoring.<\/jats:p>","DOI":"10.3390\/s20133763","type":"journal-article","created":{"date-parts":[[2020,7,6]],"date-time":"2020-07-06T09:49:11Z","timestamp":1594028951000},"page":"3763","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":43,"title":["Sensitivity Enhancement of Curvature Fiber Sensor Based on Polymer-Coated Capillary Hollow-Core Fiber"],"prefix":"10.3390","volume":"20","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6204-0193","authenticated-orcid":false,"given":"Luis A.","family":"Herrera-Piad","sequence":"first","affiliation":[{"name":"Electronics Department, DICIS, Universidad de Guanajuato, Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Salamanca 36885, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9940-2189","authenticated-orcid":false,"given":"Iv\u00e1n","family":"Hern\u00e1ndez-Romano","sequence":"additional","affiliation":[{"name":"CONACYT-Electronics Department, DICIS, Universidad de Guanajuato, Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Salamanca 36885, Mexico"}]},{"given":"Daniel A.","family":"May-Arrioja","sequence":"additional","affiliation":[{"name":"Fiber and Integrated Optics Laboratory (FIOLab), Centro de Investigaciones en \u00d3ptica A.C., Aguascalientes 20200, Mexico"}]},{"given":"Vladimir P.","family":"Minkovich","sequence":"additional","affiliation":[{"name":"Centro de Investigaciones en \u00d3ptica A.C., Calle Lomas del Bosque 115, Le\u00f3n 37150, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2408-4945","authenticated-orcid":false,"given":"Miguel","family":"Torres-Cisneros","sequence":"additional","affiliation":[{"name":"Electronics Department, DICIS, Universidad de Guanajuato, Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Salamanca 36885, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2020,7,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"102059","DOI":"10.1016\/j.yofte.2019.102059","article-title":"Photonic crystal all-fiber Mach-Zehnder interferometer sensor based on phase demodulation","volume":"53","author":"Zhao","year":"2019","journal-title":"Opt. 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