{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T01:19:52Z","timestamp":1768439992587,"version":"3.49.0"},"reference-count":96,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2012,8,2]],"date-time":"2012-08-02T00:00:00Z","timestamp":1343865600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In-line fiber optic interferometers have attracted intensive attention for their potential sensing applications in refractive index, temperature, pressure and strain measurement, etc. Typical in-line fiber-optic interferometers are of two types: Fabry-Perot interferometers and core-cladding-mode interferometers. It\u2019s known that the in-line fiber optic interferometers based on single-mode fibers can exhibit compact structures, easy fabrication and low cost. In this paper, we review two kinds of typical in-line fiber optic interferometers formed in single-mode fibers fabricated with different post-processing techniques. Also, some recently reported specific technologies for fabricating such fiber optic interferometers are presented.<\/jats:p>","DOI":"10.3390\/s120810430","type":"journal-article","created":{"date-parts":[[2012,8,2]],"date-time":"2012-08-02T11:04:55Z","timestamp":1343905495000},"page":"10430-10449","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":138,"title":["In-Line Fiber Optic Interferometric Sensors in Single-Mode Fibers"],"prefix":"10.3390","volume":"12","author":[{"given":"Tao","family":"Zhu","sequence":"first","affiliation":[{"name":"Key Laboratory of Optoelectronic Technology & Systems (Ministry of Education), Chongqing University, Chongqing 400044, China"}]},{"given":"Di","family":"Wu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Optoelectronic Technology & Systems (Ministry of Education), Chongqing University, Chongqing 400044, China"}]},{"given":"Min","family":"Liu","sequence":"additional","affiliation":[{"name":"Key Laboratory of Optoelectronic Technology & Systems (Ministry of Education), Chongqing University, Chongqing 400044, China"}]},{"given":"De-Wen","family":"Duan","sequence":"additional","affiliation":[{"name":"Key Laboratory of Optoelectronic Technology & Systems (Ministry of Education), Chongqing University, Chongqing 400044, China"}]}],"member":"1968","published-online":{"date-parts":[[2012,8,2]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"30","DOI":"10.1109\/LPT.2006.889010","article-title":"Optical refractive-index sensor based on dual fiber-Bragg gratings interposed with a multimode-fiber taper","volume":"19","author":"Shao","year":"2007","journal-title":"IEEE Photon. 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