{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,20]],"date-time":"2026-06-20T05:20:29Z","timestamp":1781932829669,"version":"3.54.5"},"reference-count":30,"publisher":"MDPI AG","issue":"1","license":[{"start":{"date-parts":[[2019,1,8]],"date-time":"2019-01-08T00:00:00Z","timestamp":1546905600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"publisher","award":["51502209"],"award-info":[{"award-number":["51502209"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"publisher"}]},{"name":"the Government Support Enterprise Development Funding of Hubei Province","award":["16441"],"award-info":[{"award-number":["16441"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A highly sensitive directional bending sensor based on a three-core fiber (TCF) Mach-Zehnder interferometer (MZI) is presented in this study. This MZI-based bending sensor was fabricated by fusion-splicing a section of TCF between two single-mode fibers (SMF) with core-offset. Due to the location of the core in the TCF, a bend applied to the TCF-based MZI led to an elongation or shortening of the core, which makes the sensor suitable for directional bending measurement. To analyze the bending characteristics, two types of TCF-based sensors, with the fusion-spliced core located at different positions between the SMFs, were investigated. A swept source was employed in the measurement technique. The experimental results showed that, for the two types of sensors in this setup, the bending sensitivities of the two sensors were 15.36 nm\/m\u22121 and 3.11 nm\/m\u22121 at the bending direction of 0\u00b0, and \u221220.48 nm\/m\u22121 and \u22125.29 nm\/m\u22121 at the bending direction of 180\u00b0. The temperature sensitivities of the two sensors were 0.043 nm\/\u00b0C and 0.041 nm\/\u00b0C, respectively. The proposed sensors are compact, versatile, inexpensive to fabricate, and are expected to have potential applications in biomedical sensing.<\/jats:p>","DOI":"10.3390\/s19010205","type":"journal-article","created":{"date-parts":[[2019,1,9]],"date-time":"2019-01-09T03:06:06Z","timestamp":1547003166000},"page":"205","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":23,"title":["In-Fiber Mach-Zehnder Interferometer Based on Three-Core Fiber for Measurement of Directional Bending"],"prefix":"10.3390","volume":"19","author":[{"given":"Lei","family":"Ding","sequence":"first","affiliation":[{"name":"Hubei Province Engineering Research Center for Intelligent Micro-Nano Medical Equipment and Key Technologies, School of Electrical and Electronics Engineering, Wuhan Textile University, Wuhan 300020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yu","family":"Li","sequence":"additional","affiliation":[{"name":"Hubei Province Engineering Research Center for Intelligent Micro-Nano Medical Equipment and Key Technologies, School of Electrical and Electronics Engineering, Wuhan Textile University, Wuhan 300020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cai","family":"Zhou","sequence":"additional","affiliation":[{"name":"Hubei Province Engineering Research Center for Intelligent Micro-Nano Medical Equipment and Key Technologies, School of Electrical and Electronics Engineering, Wuhan Textile University, Wuhan 300020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Min","family":"Hu","sequence":"additional","affiliation":[{"name":"Hubei Province Engineering Research Center for Intelligent Micro-Nano Medical Equipment and Key Technologies, School of Electrical and Electronics Engineering, Wuhan Textile University, Wuhan 300020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yuli","family":"Xiong","sequence":"additional","affiliation":[{"name":"Hubei Province Engineering Research Center for Intelligent Micro-Nano Medical Equipment and Key Technologies, School of Electrical and Electronics Engineering, Wuhan Textile University, Wuhan 300020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhongliang","family":"Zeng","sequence":"additional","affiliation":[{"name":"Hubei Province Engineering Research Center for Intelligent Micro-Nano Medical Equipment and Key Technologies, School of Electrical and Electronics Engineering, Wuhan Textile University, Wuhan 300020, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,1,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"131110","DOI":"10.1063\/1.3115029","article-title":"Tapered fiber Mach\u2013Zehnder interferometer for simultaneous measurement of refractive index and temperature","volume":"94","author":"Ping","year":"2009","journal-title":"Appl. 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