{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,9]],"date-time":"2026-04-09T06:53:20Z","timestamp":1775717600334,"version":"3.50.1"},"reference-count":56,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2019,6,27]],"date-time":"2019-06-27T00:00:00Z","timestamp":1561593600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100014440","name":"Ministerio de Ciencia, Innovaci\u00f3n y Universidades","doi-asserted-by":"publisher","award":["BIO2017-84246-C2-1-R"],"award-info":[{"award-number":["BIO2017-84246-C2-1-R"]}],"id":[{"id":"10.13039\/100014440","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100010067","name":"Gobierno de Arag\u00f3n","doi-asserted-by":"publisher","award":["Grupos DGA"],"award-info":[{"award-number":["Grupos DGA"]}],"id":[{"id":"10.13039\/501100010067","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100002924","name":"FEDER","doi-asserted-by":"publisher","award":["(EU)"],"award-info":[{"award-number":["(EU)"]}],"id":[{"id":"10.13039\/501100002924","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Optical planar waveguide sensors, able to detect and process information from the environment in a fast, cost-effective, and remote fashion, are of great interest currently in different application areas including security, metrology, automotive, aerospace, consumer electronics, energy, environment, or health. Integration of networks of these systems together with other optical elements, such as light sources, readout, or detection systems, in a planar waveguide geometry is greatly demanded towards more compact, portable, and versatile sensing platforms. Herein, we report an optical temperature sensor with a planar waveguide architecture integrating inkjet-printed luminescent light coupling-in and readout elements with matched emission and excitation. The first luminescent element, when illuminated with light in its absorption band, emits light that is partially coupled into the propagation modes of the planar waveguide. Remote excitation of this element can be performed without the need for special alignment of the light source. A thermoresponsive liquid crystal-based film regulates the amount of light coupled out from the planar waveguide at the sensing location. The second luminescent element partly absorbs the waveguided light that reaches its location and emits at longer wavelengths, serving as a temperature readout element through luminescence intensity measurements. Overall, the ability of inkjet technology to digitally print luminescent elements demonstrates great potential for the integration and miniaturization of light coupling-in and readout elements in optical planar waveguide sensing platforms.<\/jats:p>","DOI":"10.3390\/s19132856","type":"journal-article","created":{"date-parts":[[2019,6,27]],"date-time":"2019-06-27T08:47:13Z","timestamp":1561625233000},"page":"2856","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":11,"title":["Optical Planar Waveguide Sensor with Integrated Digitally-Printed Light Coupling-in and Readout Elements"],"prefix":"10.3390","volume":"19","author":[{"given":"Jorge","family":"Alam\u00e1n","sequence":"first","affiliation":[{"name":"Instituto de Ciencia de Materiales de Arag\u00f3n (ICMA), CSIC-Universidad de Zaragoza, Departamento de F\u00edsica de la Materia Condensada, 50009 Zaragoza, Spain"},{"name":"BSH Electrodom\u00e9sticos Espa\u00f1a, S.A., Pol\u00edgono Industrial de PLA-ZA, Ronda del Canal Imperial de Arag\u00f3n, 50197 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Mar\u00eda","family":"L\u00f3pez-Valdeolivas","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia de Materiales de Arag\u00f3n (ICMA), CSIC-Universidad de Zaragoza, Departamento de F\u00edsica de la Materia Condensada, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Raquel","family":"Alicante","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia de Materiales de Arag\u00f3n (ICMA), CSIC-Universidad de Zaragoza, Departamento de F\u00edsica de la Materia Condensada, 50009 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3900-2866","authenticated-orcid":false,"given":"Carlos","family":"S\u00e1nchez-Somolinos","sequence":"additional","affiliation":[{"name":"Instituto de Ciencia de Materiales de Arag\u00f3n (ICMA), CSIC-Universidad de Zaragoza, Departamento de F\u00edsica de la Materia Condensada, 50009 Zaragoza, Spain"},{"name":"Centro de Investigaci\u00f3n Biom\u00e9dica en Red de Bioingenier\u00eda, Biomateriales y Nanomedicina (CIBER-BBN), C Mariano Esquillor s.n., 50018 Zaragoza, Spain"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"203","DOI":"10.1021\/acs.analchem.5b04298","article-title":"Fiber-Optic Chemical Sensors and Biosensors (2013\u20132015)","volume":"88","author":"Wang","year":"2016","journal-title":"Anal. 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