{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,12]],"date-time":"2025-10-12T04:25:35Z","timestamp":1760243135861,"version":"build-2065373602"},"reference-count":52,"publisher":"MDPI AG","issue":"10","license":[{"start":{"date-parts":[[2015,10,15]],"date-time":"2015-10-15T00:00:00Z","timestamp":1444867200000},"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>In this work a refractive index sensor based on a combination of the  non-dispersive sensing (NDS) and the Tunable Laser Spectroscopy (TLS) principles is presented. Here, in order to have one reference and one measurement channel a single-beam dual-path configuration is used for implementing the NDS principle. These channels are monitored with a couple of identical optical detectors which are correlated to calculate the overall sensor response, called here the depth of modulation. It is shown that this is useful to minimize drifting errors due to source power variations. Furthermore, a comprehensive analysis of a refractive index sensing setup, based on an intrinsic micro Fabry-Perot Interferometer (FPI) is described. Here, the changes over the FPI pattern as the exit refractive index is varied are analytically modelled by using the characteristic matrix method. Additionally, our simulated results are supported by experimental measurements which are also provided. Finally it is shown that by using this principle a simple refractive index sensor with a resolution in the order of 2.15 \u00d7 10\u22124 RIU can be implemented by using a couple of standard and low cost photodetectors.<\/jats:p>","DOI":"10.3390\/s151026128","type":"journal-article","created":{"date-parts":[[2015,10,15]],"date-time":"2015-10-15T12:44:06Z","timestamp":1444913046000},"page":"26128-26142","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Analytical Modelling of a Refractive Index Sensor Based on  an Intrinsic Micro Fabry-Perot Interferometer"],"prefix":"10.3390","volume":"15","author":[{"given":"Everardo","family":"Vargas-Rodriguez","sequence":"first","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Gto., C.P. 38940, Mexico"}]},{"given":"Ana","family":"Guzman-Chavez","sequence":"additional","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Gto., C.P. 38940, Mexico"}]},{"given":"Martin","family":"Cano-Contreras","sequence":"additional","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Gto., C.P. 38940, Mexico"},{"name":"Departamento de Tecnolog\u00edas de la Informaci\u00f3n y Comunicaci\u00f3n, Universidad Tecnol\u00f3gica del Suroeste de Guanajuato, Carretera Valle-Huan\u00edmaro km. 1.2,  Valle de Santiago, Gto., C.P. 38400, Mexico"}]},{"given":"Eloisa","family":"Gallegos-Arellano","sequence":"additional","affiliation":[{"name":"Departamento de Estudios Multidisciplinarios, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato, Av. Universidad s\/n, Col. Yacatitas, Yuriria, Gto., C.P. 38940, Mexico"},{"name":"Departamento de Mecatr\u00f3nica, Universidad Tecnol\u00f3gica de Salamanca,  Av. Universidad Tecnol\u00f3gica #200, Col. Ciudad Baj\u00edo, Salamanca, Gto., C.P. 36766, Mexico"}]},{"given":"Daniel","family":"Jauregui-Vazquez","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato,  Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Comunidad de Palo Blanco,  Salamanca, Gto., C.P. 36885, Mexico"}]},{"given":"Juan","family":"Hern\u00e1ndez-Garc\u00eda","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato,  Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Comunidad de Palo Blanco,  Salamanca, Gto., C.P. 36885, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4010-3800","authenticated-orcid":false,"given":"Julian","family":"Estudillo-Ayala","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato,  Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Comunidad de Palo Blanco,  Salamanca, Gto., C.P. 36885, Mexico"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9487-0354","authenticated-orcid":false,"given":"Roberto","family":"Rojas-Laguna","sequence":"additional","affiliation":[{"name":"Departamento de Electr\u00f3nica, Divisi\u00f3n de Ingenier\u00edas, Universidad de Guanajuato,  Carretera Salamanca-Valle de Santiago km 3.5 + 1.8, Comunidad de Palo Blanco,  Salamanca, Gto., C.P. 36885, Mexico"}]}],"member":"1968","published-online":{"date-parts":[[2015,10,15]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Jorge, P.A.S., Silva, S.O., Gouveia, C., Tafulo, P., Coelho, L., Caldas, P., Viegas, D., Rego, G., Baptista, J.M., and Santos, J.L. 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