{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,21]],"date-time":"2025-10-21T15:23:17Z","timestamp":1761060197152,"version":"build-2065373602"},"reference-count":28,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2016,9,11]],"date-time":"2016-09-11T00:00:00Z","timestamp":1473552000000},"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>An orientation-dependent displacement sensor based on grating inscription over a fiber core and inner cladding has been demonstrated. The device comprises a short piece of multi-cladding fiber sandwiched between two standard single-mode fibers (SMFs). The grating structure is fabricated by a femtosecond laser side-illumination technique. Two well-defined resonances are achieved by the downstream both core and cladding fiber Bragg gratings (FBGs). The cladding resonance presents fiber bending dependence, together with a strong orientation dependence because of asymmetrical distribution of the \u201ccladding\u201d FBG along the fiber cross-section.<\/jats:p>","DOI":"10.3390\/s16091473","type":"journal-article","created":{"date-parts":[[2016,9,12]],"date-time":"2016-09-12T10:24:41Z","timestamp":1473675881000},"page":"1473","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Orientation-Dependent Displacement Sensor Using an Inner Cladding Fiber Bragg Grating"],"prefix":"10.3390","volume":"16","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7421-4704","authenticated-orcid":false,"given":"Tingting","family":"Yang","sequence":"first","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]},{"given":"Xueguang","family":"Qiao","sequence":"additional","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]},{"given":"Qiangzhou","family":"Rong","sequence":"additional","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]},{"given":"Weijia","family":"Bao","sequence":"additional","affiliation":[{"name":"Physics Department, Northwest University, Xi\u2019an 710069, China"}]}],"member":"1968","published-online":{"date-parts":[[2016,9,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"15555","DOI":"10.1364\/OE.15.015555","article-title":"Spectral characteristics and bend response of Bragg gratings inscribed in all-solid bandgap fibers","volume":"15","author":"Jin","year":"2007","journal-title":"Opt. 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