{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,1]],"date-time":"2026-02-01T02:42:46Z","timestamp":1769913766442,"version":"3.49.0"},"reference-count":28,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,8]],"date-time":"2023-09-08T00:00:00Z","timestamp":1694131200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"European Union\u2019s Horizon 2020 innovation program"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The use of composite materials has seen widespread adoption in modern aerospace industry. This has been facilitated due to their favourable mechanical characteristics, namely, low weight and high stiffness and strength. For broader implementation of those materials though, the out-of-autoclave production processes have to be optimized, to allow for higher reliability of the parts produced as well as cost reduction and improved production speed. This optimization can be achieved by monitoring and controlling resin filling and curing cycles. Photonic Integrated Circuits (PICs), and, in particular, Silicon Photonics, owing to their fast response, small size, ability to operate at higher temperatures, immunity to electromagnetic interference, and compatibility with CMOS fabrication techniques, can offer sensing solutions fulfilling the requirements for composite material production using carbon fibres. In this paper, we demonstrate a passive optical temperature sensor, based on a 220 nm height Silicon-on-Insulator platform, embedded in a composite tool used for producing RTM-6 composite parts of high quality (for use in the aerospace industry). The design methodology of the photonic circuit as well as the experimental results and comparison with the industry standard thermocouples during a thermal cycling of the tool are presented. The optical sensor exhibits high sensitivity (85 pm\/\u00b0C), high linearity (R2 = 0.944), and is compatible with the RTM-6 production process, operating up to 180 \u00b0C.<\/jats:p>","DOI":"10.3390\/s23187765","type":"journal-article","created":{"date-parts":[[2023,9,11]],"date-time":"2023-09-11T10:42:49Z","timestamp":1694428969000},"page":"7765","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Photonic Integrated Circuit Based Temperature Sensor for\r\nOut-of-Autoclave Composite Parts Production Monitoring"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0009-0003-6500-1661","authenticated-orcid":false,"given":"Georgios","family":"Syriopoulos","sequence":"first","affiliation":[{"name":"Photonics Communications Research Laboratory, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou, 15773 Athens, Greece"}]},{"given":"Ioannis","family":"Poulopoulos","sequence":"additional","affiliation":[{"name":"Photonics Communications Research Laboratory, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou, 15773 Athens, Greece"}]},{"given":"Charalampos","family":"Zervos","sequence":"additional","affiliation":[{"name":"Photonics Communications Research Laboratory, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou, 15773 Athens, Greece"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9228-4853","authenticated-orcid":false,"given":"Evrydiki","family":"Kyriazi","sequence":"additional","affiliation":[{"name":"Photonics Communications Research Laboratory, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou, 15773 Athens, Greece"}]},{"given":"Aggelos","family":"Poulimenos","sequence":"additional","affiliation":[{"name":"Engineering Technology Solutions E.E., 15344 Athens, Greece"}]},{"given":"Michal","family":"Szaj","sequence":"additional","affiliation":[{"name":"Argotech a.s., Holubova 978, CZ-547 01 N\u00e1chod, Czech Republic"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3470-620X","authenticated-orcid":false,"given":"Jeroen","family":"Missinne","sequence":"additional","affiliation":[{"name":"Center for Microsystem Technology (CMST), Ghent University and IMEC, Technologiepark 126, 9052 Ghent, Belgium"}]},{"given":"Geert","family":"van Steenberge","sequence":"additional","affiliation":[{"name":"Center for Microsystem Technology (CMST), Ghent University and IMEC, Technologiepark 126, 9052 Ghent, Belgium"}]},{"given":"Hercules","family":"Avramopoulos","sequence":"additional","affiliation":[{"name":"Photonics Communications Research Laboratory, National Technical University of Athens, 9 Iroon Polytechniou Street, Zografou, 15773 Athens, Greece"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Parveez, B., Kittur, M.I., Badruddin, I.A., Kamangar, S., Hussien, M., and Umarfarooq, M.A. (2022). 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