{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,17]],"date-time":"2026-03-17T14:24:31Z","timestamp":1773757471325,"version":"3.50.1"},"reference-count":52,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2012,6,18]],"date-time":"2012-06-18T00:00:00Z","timestamp":1339977600000},"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>A review of refractive index measurement based on different types of optical fiber sensor configurations and techniques is presented. It addresses the main developments in the area, with particular focus on results obtained at INESC Porto, Portugal. The optical fiber sensing structures studied include those based on Bragg and long period gratings, on micro-interferometers, on plasmonic effects in fibers and on multimode interference in a large spectrum of standard and microstructured optical fibers.<\/jats:p>","DOI":"10.3390\/s120608371","type":"journal-article","created":{"date-parts":[[2012,6,18]],"date-time":"2012-06-18T14:31:40Z","timestamp":1340029900000},"page":"8371-8389","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":30,"title":["Fiber Optic-Based Refractive Index Sensing at INESC Porto"],"prefix":"10.3390","volume":"12","author":[{"given":"Pedro A. S.","family":"Jorge","sequence":"first","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]},{"given":"Susana O.","family":"Silva","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]},{"given":"Carlos","family":"Gouveia","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Centro de Compet\u00eancia de Ci\u00eancias Exatas e da Engenharia, Universidade da Madeira, Campus da Penteada, Funchal 9000-390, Portugal"}]},{"given":"Paula","family":"Tafulo","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]},{"given":"Luis","family":"Coelho","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]},{"given":"Paulo","family":"Caldas","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Escola Superior de Tecnologia e Gest\u00e3o de Viana do Castelo, Av. do Atl\u00e2ntico, Apartado 574, Viana do Castelo 4900-348, Portugal"}]},{"given":"Diana","family":"Viegas","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]},{"given":"Gaspar","family":"Rego","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Escola Superior de Tecnologia e Gest\u00e3o de Viana do Castelo, Av. do Atl\u00e2ntico, Apartado 574, Viana do Castelo 4900-348, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4111-1095","authenticated-orcid":false,"given":"Jos\u00e9 M.","family":"Baptista","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Centro de Compet\u00eancia de Ci\u00eancias Exatas e da Engenharia, Universidade da Madeira, Campus da Penteada, Funchal 9000-390, Portugal"}]},{"given":"Jos\u00e9 L.","family":"Santos","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"},{"name":"Faculdade de Ci\u00eancias da Universidade do Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]},{"given":"Orlando","family":"Fraz\u00e3o","sequence":"additional","affiliation":[{"name":"INESC Porto, Rua do Campo Alegre 687, Porto 4169-007, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2012,6,18]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"3070","DOI":"10.1364\/AO.22.003070","article-title":"Refractive-index measurements of liquids used in conjunction with optical fibers","volume":"22","author":"Cooper","year":"1983","journal-title":"Appl. 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