{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T20:44:35Z","timestamp":1775853875922,"version":"3.50.1"},"reference-count":36,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2018,6,5]],"date-time":"2018-06-05T00:00:00Z","timestamp":1528156800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"PolyU Strategic Development Special Project","award":["1-ZVGB"],"award-info":[{"award-number":["1-ZVGB"]}]},{"name":"PolyU General Research Fund","award":["G-YBLJ"],"award-info":[{"award-number":["G-YBLJ"]}]},{"name":"PolyU General Research Fund","award":["1-ZVHB"],"award-info":[{"award-number":["1-ZVHB"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Miniature optical fiber-tip sensors based on directly \u00b5-printed polymer suspended-microbeams are presented. With an in-house optical 3D \u03bc-printing technology, SU-8 suspended-microbeams are fabricated in situ to form Fabry\u2013P\u00e9rot (FP) micro-interferometers on the end face of standard single-mode optical fiber. Optical reflection spectra of the fabricated FP micro-interferometers are measured and fast Fourier transform is applied to analyze the cavity of micro-interferometers. The applications of the optical fiber-tip sensors for refractive index (RI) sensing and pressure sensing, which showed 917.3 nm\/RIU to RI change and 4.29 nm\/MPa to pressure change, respectively, are demonstrated in the experiments. The sensors and their optical \u00b5-printing method unveil a new strategy to integrate complicated microcomponents on optical fibers toward \u2018lab-on-fiber\u2019 devices and applications.<\/jats:p>","DOI":"10.3390\/s18061825","type":"journal-article","created":{"date-parts":[[2018,6,5]],"date-time":"2018-06-05T04:16:43Z","timestamp":1528172203000},"page":"1825","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":31,"title":["Optical Fiber-Tip Sensors Based on In-Situ \u00b5-Printed Polymer Suspended-Microbeams"],"prefix":"10.3390","volume":"18","author":[{"given":"Mian","family":"Yao","sequence":"first","affiliation":[{"name":"Photonics Research Centre, Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hong Kong, China"},{"name":"Photonics Research Centre, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2044-7817","authenticated-orcid":false,"given":"Xia","family":"Ouyang","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jushuai","family":"Wu","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"A. Ping","family":"Zhang","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hwa-Yaw","family":"Tam","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"P. K. A.","family":"Wai","sequence":"additional","affiliation":[{"name":"Photonics Research Centre, Department of Electronic and Information Engineering, The Hong Kong Polytechnic University, Hong Kong, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,6,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Yin, S., and Yu, F.T.S. (2002). Fiber Optic Sensors, CRC Press. 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