{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,1]],"date-time":"2026-08-01T16:46:30Z","timestamp":1785602790012,"version":"3.56.0"},"reference-count":112,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2019,5,4]],"date-time":"2019-05-04T00:00:00Z","timestamp":1556928000000},"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>Optical gas sensors play an increasingly important role in many applications. Sensing techniques based on mid-infrared absorption spectroscopy offer excellent stability, selectivity and sensitivity, for numerous possibilities expected for sensors integrated into mobile and wearable devices. Here we review recent progress towards the miniaturization and integration of optical gas sensors, with a focus on low-cost and low-power consumption devices.<\/jats:p>","DOI":"10.3390\/s19092076","type":"journal-article","created":{"date-parts":[[2019,5,9]],"date-time":"2019-05-09T11:22:35Z","timestamp":1557400955000},"page":"2076","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":284,"title":["Towards Integrated Mid-Infrared Gas Sensors"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5708-743X","authenticated-orcid":false,"given":"Daniel","family":"Popa","sequence":"first","affiliation":[{"name":"Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Florin","family":"Udrea","sequence":"additional","affiliation":[{"name":"Department of Engineering, University of Cambridge, Cambridge CB3 0FA, UK"},{"name":"ams Sensors UK Limited, Cambridge CB4 0DL, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,5,4]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"11877","DOI":"10.1021\/acs.chemrev.6b00187","article-title":"Multivariable Sensors for Ubiquitous Monitoring of Gases in the Era of Internet of Things and Industrial Internet","volume":"116","author":"Potyrailo","year":"2016","journal-title":"Chem. 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