{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,28]],"date-time":"2026-07-28T02:53:43Z","timestamp":1785207223833,"version":"3.55.0"},"reference-count":125,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2014,2,26]],"date-time":"2014-02-26T00:00:00Z","timestamp":1393372800000},"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>This review offers new perspectives on the subject and highlights an area in need of further research. It includes an analysis of current scientific literature mainly covering the last decade and examines the trends in the development of electronic, acoustic and optical-fiber humidity sensors over this period. The major findings indicate that a new generation of sensor technology based on optical fibers is emerging. The current trends suggest that electronic humidity sensors could soon be replaced by sensors that are based on photonic structures. Recent scientific advances are expected to allow dedicated systems to avoid the relatively high price of interrogation modules that is currently a major disadvantage of fiber-based sensors.<\/jats:p>","DOI":"10.3390\/s140303986","type":"journal-article","created":{"date-parts":[[2014,2,26]],"date-time":"2014-02-26T11:03:00Z","timestamp":1393412580000},"page":"3986-4013","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":127,"title":["Toward a New Generation of Photonic Humidity Sensors"],"prefix":"10.3390","volume":"14","author":[{"given":"Stanislav","family":"Kolpakov","sequence":"first","affiliation":[{"name":"School of Engineering and Applied Science, Aston University, Aston Triangle, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Neil","family":"Gordon","sequence":"additional","affiliation":[{"name":"School of Engineering and Applied Science, Aston University, Aston Triangle, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chengbo","family":"Mou","sequence":"additional","affiliation":[{"name":"School of Engineering and Applied Science, Aston University, Aston Triangle, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kaiming","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Engineering and Applied Science, Aston University, Aston Triangle, Birmingham B4 7ET, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2014,2,26]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"5","DOI":"10.1023\/A:1007380021895","article-title":"An apnea monitor using a rapid-response hygrometer","volume":"13","author":"Tatara","year":"1997","journal-title":"J. Clin. Monit. Comput."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"450","DOI":"10.1002\/mop.27322","article-title":"Breath sensor based on reflective optical lensed fiber","volume":"55","author":"Lin","year":"2013","journal-title":"Microw. Opt. Technol. Lett."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1178","DOI":"10.1109\/JPROC.2005.849726","article-title":"Communication systems for building automation and control","volume":"93","author":"Kastner","year":"2005","journal-title":"Proc. IEEE"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"1162","DOI":"10.1109\/TBME.2002.802052","article-title":"Interdigitated humidity sensors for a portable clinical microsystem","volume":"49","author":"Laville","year":"2002","journal-title":"IEEE Trans. Biomed. Eng."},{"key":"ref_5","unstructured":"Habib Ahsan, A.H.M., Lange, C.F., and Moussa, W. (2003, January 20\u201323). Development of a Humidity Microsensor with Thermal Reset. Banff, AB, Canada."},{"key":"ref_6","unstructured":"Chairperson Publications Board (2008). Guide to Meteorological Instruments and Methods of Observation, World Meteorological Organization. [7th ed.]."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"085021","DOI":"10.1088\/0960-1317\/22\/8\/085021","article-title":"Designing a robust high-speed CMOS-MEMS capacitive humidity sensor","volume":"22","author":"Lazarus","year":"2012","journal-title":"J. Micromech. Microeng."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1341","DOI":"10.1049\/el.2010.2080","article-title":"Humidity sensor based on a photonic crystal fibre interferometer","volume":"46","author":"Mathew","year":"2010","journal-title":"Electron. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"037006","DOI":"10.1117\/1.JBO.17.3.037006","article-title":"Microstructured optical fiber interferometric breathing sensor","volume":"17","author":"Favero","year":"2012","journal-title":"J. Biomed. Opt."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"264","DOI":"10.1016\/j.snb.2012.09.098","article-title":"Fiber humidity sensors with high sensitivity and selectivity based on interior nanofilm-coated photonic crystal fiber long-period gratings","volume":"176","author":"Zheng","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"2349","DOI":"10.3390\/s130202349","article-title":"High-visibility photonic crystal fiber interferometer as multifunctional sensor","volume":"13","author":"Favero","year":"2013","journal-title":"Sensors"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"1159","DOI":"10.1109\/19.746575","article-title":"Quartz sensor for water absorption measurement in glass-fiber resins","volume":"47","author":"Matko","year":"1998","journal-title":"Instrum. Meas. IEEE Trans."},{"key":"ref_13","unstructured":"Matko, V., and Donlagic, D. (1996, January 17\u201321). Sensor for High-Air-Humidity Measurement. Braunschweig, Germany."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"332001","DOI":"10.1088\/0957-4484\/19\/33\/332001","article-title":"Recent progress in carbon nanotube-based gas sensors","volume":"19","author":"Zhang","year":"2008","journal-title":"Nanotechnology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"600","DOI":"10.1016\/j.physe.2008.10.016","article-title":"Investigation of capacitive humidity sensing behavior of silicon nanowires","volume":"41","author":"Li","year":"2009","journal-title":"Phys. E Low-Dimens. Syst. Nanostruct."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"6550","DOI":"10.1002\/anie.200704488","article-title":"Carbon nanotube gas and vapor sensors","volume":"47","author":"Kauffman","year":"2008","journal-title":"Angew. Chem. Int. Ed."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"120","DOI":"10.1016\/j.snb.2009.11.041","article-title":"Novel resistive-type humidity sensor based on multiwall carbon nanotube\/polyimide composite films","volume":"145","author":"Yoo","year":"2010","journal-title":"Sens. Actuators B Chem."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"5441","DOI":"10.1088\/0957-4484\/17\/21\/026","article-title":"Carbon nanotube-enhanced capillary condensation for a capacitive humidity sensor","volume":"17","author":"Yeow","year":"2006","journal-title":"Nanotechnology"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"955","DOI":"10.1109\/JSEN.2007.897363","article-title":"Capacitive humidity sensors with high sensitivity and subsecond response times","volume":"7","author":"Steele","year":"2007","journal-title":"IEEE Sens. J."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"3615","DOI":"10.3390\/s130303615","article-title":"A humidity sensing organic-inorganic composite for environmental monitoring","volume":"13","author":"Ahmad","year":"2013","journal-title":"Sensors"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Bi, H., Yin, K., Xie, X., Ji, J., Wan, S., Sun, L., Terrones, M., and Dresselhaus, M.S. (2013). Ultrahigh humidity sensitivity of graphene oxide. Sci. Rep.","DOI":"10.1038\/srep02714"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"7431","DOI":"10.3390\/s90907431","article-title":"A capacitive humidity sensor based on multi-wall carbon nanotubes (MWCNTs)","volume":"9","author":"Chen","year":"2009","journal-title":"Sensors"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"702","DOI":"10.1109\/16.830983","article-title":"A high-speed capacitive humidity sensor with on-chip thermal reset","volume":"47","author":"Kang","year":"2000","journal-title":"IEEE Trans. Electron Devices"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"8674","DOI":"10.3390\/s110908674","article-title":"Real-time remote monitoring of temperature and humidity within a proton exchange membrane fuel cell using flexible sensors","volume":"11","author":"Kuo","year":"2011","journal-title":"Sensors"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"3363","DOI":"10.3390\/s100403363","article-title":"Sensor fabrication method for in situ temperature and humidity monitoring of light emitting diodes","volume":"10","author":"Lee","year":"2010","journal-title":"Sensors"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"2715","DOI":"10.3390\/s110302715","article-title":"Wireless remote weather monitoring system based on MEMS technologies","volume":"11","author":"Ma","year":"2011","journal-title":"Sensors"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"6197","DOI":"10.3390\/s110606197","article-title":"A standard CMOS humidity sensor without post-processing","volume":"11","author":"Nizhnik","year":"2011","journal-title":"Sensors"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"226","DOI":"10.3390\/s120100226","article-title":"Self-calibrated humidity sensor in CMOS without post-processing","volume":"12","author":"Nizhnik","year":"2012","journal-title":"Sensors"},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"10095","DOI":"10.3390\/s101110095","article-title":"Polypyrrole porous micro humidity sensor integrated with a ring oscillator circuit on chip","volume":"10","author":"Yang","year":"2010","journal-title":"Sensors"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"3135","DOI":"10.3390\/s110303135","article-title":"A high temperature capacitive humidity sensor based on mesoporous silica","volume":"11","author":"Wagner","year":"2011","journal-title":"Sensors"},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"287","DOI":"10.1016\/j.jallcom.2006.05.091","article-title":"Structural and optical properties of nanostructured TiO2 thin films fabricated by glancing angle deposition","volume":"431","author":"Wang","year":"2007","journal-title":"J. Alloy. Compd."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"205","DOI":"10.3390\/s20600205","article-title":"Thin films of In2O3\/SiO for humidity sensing applications","volume":"2","author":"Arshaka","year":"2002","journal-title":"Sensors"},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"50","DOI":"10.3390\/s20200050","article-title":"A ceramic thick film humidity sensor based on MnZn ferrite","volume":"2","author":"Arshaka","year":"2002","journal-title":"Sensors"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"6070","DOI":"10.1021\/ja070788m","article-title":"High-sensitivity humidity sensor based on a single SnO2 nanowire","volume":"129","author":"Kuang","year":"2007","journal-title":"J. Am. Chem. Soc."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"1508","DOI":"10.3390\/s8031508","article-title":"Synthesis and characterization of carbon nitride films for micro humidity sensors","volume":"8","author":"Lee","year":"2008","journal-title":"Sensors"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"11592","DOI":"10.3390\/s120911592","article-title":"A fully integrated humidity sensor system-on-chip fabricated by micro-stamping technology","volume":"12","author":"Huang","year":"2012","journal-title":"Sensors"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"2023","DOI":"10.3390\/s130202023","article-title":"Characterization of a sulfonated polycarbonate resistive humidity sensor","volume":"13","author":"Rubinger","year":"2013","journal-title":"Sensors"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"8143","DOI":"10.3390\/s110808143","article-title":"Fabrication and characterization of polyaniline\/PVA humidity microsensors","volume":"11","author":"Yang","year":"2011","journal-title":"Sensors"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"162","DOI":"10.1016\/S0924-4247(99)00004-7","article-title":"Surface acoustic wave humidity sensor using polyvinyl-alcohol film","volume":"76","author":"Penza","year":"1999","journal-title":"Sens. Actuators A Phys."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"707","DOI":"10.1088\/0964-1726\/6\/6\/007","article-title":"Surface acoustic wave humidity sensors: a comparison between different types of sensitive membrane","volume":"6","author":"Caliendo","year":"1997","journal-title":"Smart Mater. Struct."},{"key":"ref_41","first-page":"155","article-title":"The use of quartz oscillators for weighing thin layers and for microweighing (In German)","volume":"155","author":"Sauerbrey","year":"1959","journal-title":"Zeitschrift f\u00fcr Physik"},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"265504","DOI":"10.1088\/0957-4484\/22\/26\/265504","article-title":"A surface acoustic wave humidity sensor with high sensitivity based on electrospun MWCNT\/Nafion nanofiber films","volume":"22","author":"Sheng","year":"2011","journal-title":"Nanotechnology"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"347","DOI":"10.1016\/j.snb.2006.12.048","article-title":"A highly water-resistive humidity sensor based on silicon-containing polyelectrolytes prepared by one-pot method","volume":"124","author":"Lv","year":"2007","journal-title":"Sens. Actuators B Chem."},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"516","DOI":"10.1016\/j.snb.2009.12.062","article-title":"A surface acoustic wave humidity sensor based on electrosprayed silicon-containing polyelectrolyte","volume":"145","author":"Li","year":"2010","journal-title":"Sens. Actuators B Chem."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"300","DOI":"10.1016\/S0925-4005(00)00448-2","article-title":"Relative humidity sensing by PVA-coated dual resonator SAW oscillator","volume":"68","author":"Penza","year":"2000","journal-title":"Sens Actuators B Chem."},{"key":"ref_46","unstructured":"Braga, E., Nakano, A., and da Cunha, M. (1999, January 9\u201312). A SAW Resonator Sensor System Employed in Humidity Measurements. Rio de Janeiro, Brazil."},{"key":"ref_47","doi-asserted-by":"crossref","first-page":"2019","DOI":"10.1109\/TIM.2008.917255","article-title":"A new high-frequency surface acoustic wave sensor for humidity measurement","volume":"57","author":"Kawalec","year":"2008","journal-title":"Instrum. Meas. IEEE Trans."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"123","DOI":"10.1140\/epjst\/e2008-00529-x","article-title":"Measurements results of SAW humidity sensor with nafion layer","volume":"154","author":"Kawalec","year":"2008","journal-title":"Eur. Phys. J. Spec. Top."},{"key":"ref_49","doi-asserted-by":"crossref","unstructured":"Rimeika, R., Ciplys, D., Poderys, V., Rotomskis, R., and Shur, M. (2009, January 25\u201328). Humidity Sensor Using Leaky Surface Acoustic Waves in YX-LiTaO3 with Nanostructured Porphyrin Film. Christchurch, New Zealand.","DOI":"10.1109\/ICSENS.2009.5398474"},{"key":"ref_50","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1016\/j.snb.2009.10.053","article-title":"Highly stable and sensitive humidity sensors based on quartz crystal microbalance coated with hexagonal lamelliform monodisperse mesoporous silica SBA-15 thin film","volume":"144","author":"Zhu","year":"2010","journal-title":"Sens. Actuators B Chem."},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"299","DOI":"10.1016\/j.snb.2006.08.034","article-title":"Humidity sensor based on quartz tuning fork coated with solgel-derived nanocrystalline zinc oxide thin film","volume":"123","author":"Zhou","year":"2007","journal-title":"Sens. Actuators B Chem."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"629","DOI":"10.1016\/j.tsf.2009.07.059","article-title":"A hybrid humidity sensor using optical waveguides on a quartz crystal microbalance","volume":"518","author":"Shinbo","year":"2009","journal-title":"Thin Solid Films"},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"338","DOI":"10.1016\/j.snb.2005.09.019","article-title":"A low humidity sensor made of quartz crystal microbalance coated with multi-walled carbon nanotubes\/Nafion composite material films","volume":"115","author":"Su","year":"2006","journal-title":"Sens. Actuators B Chem."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"915","DOI":"10.1016\/j.snb.2007.10.006","article-title":"Low-humidity sensor based on a quartz-crystal microbalance coated with polypyrrole\/Ag\/TiO2 nanoparticles composite thin films","volume":"129","author":"Su","year":"2008","journal-title":"Sens. Actuators B Chem."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"055502","DOI":"10.1088\/0957-4484\/21\/5\/055502","article-title":"A highly sensitive humidity sensor based on a nanofibrous membrane coated quartz crystal microbalance","volume":"21","author":"Wang","year":"2010","journal-title":"Nanotechnology"},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"421","DOI":"10.1016\/j.snb.2005.10.005","article-title":"Humidity sensitive properties of ZnO nanotetrapods investigated by a quartz crystal microbalance","volume":"115","author":"Wang","year":"2006","journal-title":"Sens. Actuators B Chem."},{"key":"ref_57","doi-asserted-by":"crossref","first-page":"142","DOI":"10.1016\/j.sna.2004.11.032","article-title":"Quartz crystal microbalance coated with carbon nanotube films used as humidity sensor","volume":"120","author":"Zhang","year":"2005","journal-title":"Sens. Actuators A Phys."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1016\/j.physb.2005.07.001","article-title":"Detection of humidity based on quartz crystal microbalance coated with ZnO nanostructure films","volume":"368","author":"Zhang","year":"2005","journal-title":"Phys. B Condens. Matter."},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"209","DOI":"10.1016\/j.sna.2006.07.001","article-title":"Humidity detection by nanostructured ZnO: A wireless quartz crystal microbalance investigation","volume":"135","author":"Zhou","year":"2007","journal-title":"Sens. Actuators A Phys."},{"key":"ref_60","doi-asserted-by":"crossref","unstructured":"Fu, J., and Ayazi, F. (2010, January 1\u20134). Dual-Mode Piezo-on-Silicon Resonant Temperature and Humidity Sensor for Portable Air Quality Monitoring Systems. Kona, HI, USA.","DOI":"10.1109\/ICSENS.2010.5690510"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"1902","DOI":"10.1109\/TUFFC.2010.1637","article-title":"The effects of relative humidity and reducing gases on the temperature coefficient of resonant frequency of ZnO based film bulk acoustic wave resonator","volume":"57","author":"Qiu","year":"2010","journal-title":"IEEE Trans. Ultrason. Ferroelectr. Freq. Control"},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"516","DOI":"10.1016\/S0925-4005(98)00131-2","article-title":"Surface acoustic wave humidity sensor based on a thin PolyXIO film","volume":"49","author":"Tashtoush","year":"1998","journal-title":"Sens. Actuators B Chem."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"560","DOI":"10.1016\/j.snb.2006.06.031","article-title":"Surface acoustic wave humidity sensors based on poly(p-diethynylbenzene) and sodium poly sulfone sulfonate","volume":"122","author":"Li","year":"2007","journal-title":"Sens. Actuators B Chem."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/S0925-4005(01)00937-6","article-title":"SAW chemical sensing using poly-ynes and organometallic polymer films","volume":"81","author":"Penza","year":"2001","journal-title":"Sens. Actuators B Chem."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1016\/S0925-4005(01)01018-8","article-title":"High surface area polymer coatings for SAW-based chemical sensor applications","volume":"82","author":"Levit","year":"2002","journal-title":"Sens. Actuators B Chem."},{"key":"ref_66","doi-asserted-by":"crossref","first-page":"516","DOI":"10.1016\/j.snb.2009.12.062","article-title":"A surface acoustic wave humidity sensor based on electrosprayed silicon-containing polyelectrolyte","volume":"145","author":"Li","year":"2010","journal-title":"Sens. Actuators B Chem."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.snb.2003.07.016","article-title":"Gas-detecting properties of surface acoustic wave ammonia sensors","volume":"101","author":"Shen","year":"2004","journal-title":"Sens. Actuators B Chem."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"756","DOI":"10.1016\/j.snb.2005.07.051","article-title":"Deposition of polymer coatings onto SAW resonators using AC electrospray","volume":"114","author":"Sarkar","year":"2006","journal-title":"Sens. Actuators B Chem."},{"key":"ref_69","doi-asserted-by":"crossref","first-page":"444","DOI":"10.1016\/j.snb.2011.04.080","article-title":"Thin polymer film based rapid surface acoustic wave humidity sensors","volume":"156","author":"Buvailo","year":"2011","journal-title":"Sens. Actuators B Chem."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/j.snb.2011.06.042","article-title":"Fiber optic humidity sensors for high-energy physics applications at CERN","volume":"159","author":"Consales","year":"2011","journal-title":"Sens. Actuators B Chem."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"11407","DOI":"10.3390\/s130911407","article-title":"Study of the effect of the strategy of heating on the mudejar church of Santa Maria in Ateca (Spain) for preventive conservation of the altarpiece surroundings","volume":"13","author":"Beltran","year":"2013","journal-title":"Sensors"},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"450","DOI":"10.1002\/mop.27322","article-title":"Breath sensor based on reflective optical lensed fiber","volume":"55","author":"Lin","year":"2013","journal-title":"Microw. Opt. Technol. Lett."},{"key":"ref_73","doi-asserted-by":"crossref","unstructured":"Xu, L., Fanguy, J.C., Soni, K., and Tao, S. (2004). Optical fiber humidity sensor based on evanescent-wavescattering. Opt. Lett., 1191\u20131193.","DOI":"10.1364\/OL.29.001191"},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"1082","DOI":"10.1109\/JSEN.2005.847935","article-title":"Polymer-coated fiber Bragg grating for relative humidity sensing","volume":"5","author":"Yeo","year":"2005","journal-title":"IEEE Sens. J."},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"518","DOI":"10.1016\/j.snb.2007.05.007","article-title":"Low-cost relative humidity sensor based on thermoplastic polyimide-coated fiber Bragg grating","volume":"127","author":"Huang","year":"2007","journal-title":"Sens. Actuators B Chem."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"1002","DOI":"10.1016\/j.electacta.2008.08.023","article-title":"Di-ureasil xerogels containing lithium bis(trifluoromethanesulfonyl)imide for application in solid-state electrochromic devices","volume":"54","author":"Barbosa","year":"2009","journal-title":"Electrochim. Acta"},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"8847","DOI":"10.3390\/s120708847","article-title":"Optical fiber relative humidity sensor based on a FBG with a di-ureasil coating","volume":"12","author":"Correia","year":"2012","journal-title":"Sensors"},{"key":"ref_78","doi-asserted-by":"crossref","first-page":"94","DOI":"10.1016\/j.snb.2012.10.047","article-title":"Radiation hard humidity sensors for high energy physics applications using polyimide-coated fiber Bragg gratings sensors","volume":"177","author":"Berruti","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_79","doi-asserted-by":"crossref","first-page":"4140","DOI":"10.1364\/OE.19.004140","article-title":"Optical fiber relative humidity sensor based on FBG incorporated thin-core fiber modal interferometer","volume":"19","author":"Gu","year":"2011","journal-title":"Opt. Express"},{"key":"ref_80","doi-asserted-by":"crossref","first-page":"1553","DOI":"10.1109\/JSTQE.2011.2182337","article-title":"Relative humidity sensor based on an agarose-infiltrated photonic crystal fiber interferometer","volume":"18","author":"Mathew","year":"2012","journal-title":"IEEE J. Sel. Top. Quantum Electron."},{"key":"ref_81","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1016\/j.snb.2012.04.052","article-title":"Chitosan based fiber-optic Fabry-Perot humidity sensor","volume":"169","author":"Chen","year":"2012","journal-title":"Sens. Actuators B Chem."},{"key":"ref_82","doi-asserted-by":"crossref","first-page":"573","DOI":"10.1016\/j.snb.2005.07.006","article-title":"Humidity sensing with a luminescent Ru(II) complex and phase-sensitive detection","volume":"113","author":"Bedoya","year":"2006","journal-title":"Sens. Actuators B Chem."},{"key":"ref_83","doi-asserted-by":"crossref","first-page":"5493","DOI":"10.1364\/AO.52.005493","article-title":"Zinc oxide nanoparticle-doped nanoporous solgel fiber as a humidity sensor with enhanced sensitivity and large linear dynamic range","volume":"52","author":"Aneesh","year":"2013","journal-title":"Appl. Opt."},{"key":"ref_84","doi-asserted-by":"crossref","first-page":"281","DOI":"10.1109\/JSEN.2008.917487","article-title":"Optical fiber humidity sensors using nanostructured coatings of SiO2 nanoparticles","volume":"8","author":"Corres","year":"2008","journal-title":"IEEE Sens. J."},{"key":"ref_85","doi-asserted-by":"crossref","first-page":"122","DOI":"10.1016\/j.snb.2010.06.012","article-title":"A fibre-optic humidity sensor based on a porous silica xerogel film as the sensing element","volume":"149","author":"Estella","year":"2010","journal-title":"Sens. Actuators B Chem."},{"key":"ref_86","doi-asserted-by":"crossref","first-page":"085103","DOI":"10.1088\/0957-0233\/23\/8\/085103","article-title":"Optical relative humidity sensor based on a hollow core-photonic bandgap fiber","volume":"23","author":"Noor","year":"2012","journal-title":"Meas. Sci. Technol."},{"key":"ref_87","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1016\/j.snb.2012.07.010","article-title":"Optical fiber humidity sensors based on Localized Surface Plasmon Resonance (LSPR) and Lossy-mode resonance (LMR) in overlays loaded with silver nanoparticles","volume":"173","author":"Rivero","year":"2012","journal-title":"Sens. Actuators B Chem."},{"key":"ref_88","doi-asserted-by":"crossref","unstructured":"Wang, B., Zhang, F., Pang, F., and Wang, T. (2011, January 13\u201316). An Optical Fiber Humidity Sensor Based on Optical Absorption. Shanghai, China.","DOI":"10.1364\/ACP.2011.83112A"},{"key":"ref_89","doi-asserted-by":"crossref","first-page":"47","DOI":"10.1016\/j.sna.2011.11.029","article-title":"A fiber bend based humidity sensor with a wide linear range and fast measurement speed","volume":"174","author":"Mathew","year":"2012","journal-title":"Sens. Actuators A Phys."},{"key":"ref_90","doi-asserted-by":"crossref","first-page":"13349","DOI":"10.1364\/OE.16.013349","article-title":"Fast detection of humidity with a subwavelength-diameter fiber taper coated with gelatin film","volume":"16","author":"Zhang","year":"2008","journal-title":"Opt. Express"},{"key":"ref_91","doi-asserted-by":"crossref","first-page":"2205","DOI":"10.1109\/JSEN.2011.2181358","article-title":"Humidity sensor based on a multimode-fiber taper coated With polyvinyl alcohol interacting with a fiber bragg grating","volume":"12","author":"Li","year":"2012","journal-title":"IEEE Sens. J."},{"key":"ref_92","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1109\/LPT.2009.2013185","article-title":"Relative humidity sensor based on tilted fiber bragg grating with polyvinyl alcohol coating","volume":"21","author":"Miao","year":"2009","journal-title":"IEEE Photonics Technol. Lett."},{"key":"ref_93","doi-asserted-by":"crossref","first-page":"148","DOI":"10.1016\/j.snb.2005.01.033","article-title":"Characterisation of a polymer-coated fibre Bragg grating sensor for relative humidity sensing","volume":"110","author":"Yeo","year":"2005","journal-title":"Sens. Actuators B Chem."},{"key":"ref_94","doi-asserted-by":"crossref","first-page":"563","DOI":"10.1016\/j.snb.2012.07.032","article-title":"Polyvinyl alcohol coated photonic crystal optical fiber sensor for humidity measurement","volume":"174","author":"Wong","year":"2012","journal-title":"Sens. Actuators B Chem."},{"key":"ref_95","doi-asserted-by":"crossref","first-page":"643","DOI":"10.1049\/el.2010.0879","article-title":"Optical fibre temperature and humidity sensor","volume":"46","author":"Zhang","year":"2010","journal-title":"Electron. Lett."},{"key":"ref_96","doi-asserted-by":"crossref","first-page":"034002","DOI":"10.1088\/0957-0233\/20\/3\/034002","article-title":"A fibre optic humidity sensor based on a long-period fibre grating coated with a thin film of SiO2 nanospheres","volume":"20","author":"Viegas","year":"2009","journal-title":"Meas. Sci. Technol."},{"key":"ref_97","doi-asserted-by":"crossref","first-page":"037006","DOI":"10.1117\/1.JBO.17.3.037006","article-title":"Microstructured optical fiber interferometric breathing sensor","volume":"17","author":"Favero","year":"2012","journal-title":"J. Biomed. Opt."},{"key":"ref_98","doi-asserted-by":"crossref","first-page":"1597","DOI":"10.1109\/JSTQE.2012.2194729","article-title":"Chitosan-coated polarization maintaining relative humidity measurement","volume":"18","author":"Chen","year":"2012","journal-title":"IEEE J. Sel. Top. Quantum Electron."},{"key":"ref_99","doi-asserted-by":"crossref","unstructured":"Mathew, J., Semenova, Y., and Farrell, G. (2011, January 28\u201331). A Miniature Optical Humidity Sensor. Limerick, Ireland.","DOI":"10.1109\/ICSENS.2011.6127067"},{"key":"ref_100","doi-asserted-by":"crossref","first-page":"1341","DOI":"10.1049\/el.2010.2080","article-title":"Humidity sensor based on photonic crystal fibre interferometer","volume":"46","author":"Mathew","year":"2010","journal-title":"Electron. Lett."},{"key":"ref_101","doi-asserted-by":"crossref","first-page":"2364","DOI":"10.1002\/mop.27085","article-title":"Relative humidity sensor based on polarization maintainig fiber","volume":"54","author":"Liang","year":"2012","journal-title":"Microw. Opt. Technol. Lett."},{"key":"ref_102","doi-asserted-by":"crossref","first-page":"167","DOI":"10.1070\/PU2006v049n02ABEH005784","article-title":"Cladding modes of optical fibers: properties and applications","volume":"49","author":"Ivanov","year":"2006","journal-title":"Phys.-Uspekhi"},{"key":"ref_103","doi-asserted-by":"crossref","first-page":"65","DOI":"10.1070\/QE1999v029n01ABEH001413","article-title":"Properties of the cladding modes of an optical fibre excited by refractive-index gratings","volume":"29","author":"Dianov","year":"1999","journal-title":"Quantum Electron."},{"key":"ref_104","doi-asserted-by":"crossref","first-page":"694","DOI":"10.1016\/j.snb.2012.11.062","article-title":"Fibre optic long period grating-based humidity sensor probe using a Michelson interferometric arrangement","volume":"178","author":"Alwis","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_105","doi-asserted-by":"crossref","first-page":"1760","DOI":"10.1364\/JOSAA.14.001760","article-title":"Cladding-mode resonances in short- and long-period fiber grating filters","volume":"14","author":"Erdogan","year":"1997","journal-title":"J. Opt. Soc. Am. A"},{"key":"ref_106","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1007\/s10043-011-0038-7","article-title":"Fiber-optic humidity sensor based on an air-gap long period fiber grating","volume":"18","author":"Fu","year":"2011","journal-title":"Opt. Rev."},{"key":"ref_107","doi-asserted-by":"crossref","first-page":"4567","DOI":"10.1364\/AO.45.004567","article-title":"Optical fiber long-period grating humidity sensor with poly(ethylene oxide)\/cobalt chloride coating","volume":"45","author":"Konstantaki","year":"2006","journal-title":"Appl. Opt."},{"key":"ref_108","doi-asserted-by":"crossref","first-page":"085301","DOI":"10.1088\/0957-0233\/19\/8\/085301","article-title":"Refractive index sensing of fiber optic long-period grating structures coated with a plasma deposited diamond-like carbon thin film","volume":"19","author":"Smietana","year":"2008","journal-title":"Meas. Sci. Technol."},{"key":"ref_109","doi-asserted-by":"crossref","first-page":"3131","DOI":"10.1088\/0957-0233\/18\/10\/S13","article-title":"A relative humidity sensor using a hydrogel-coated long period grating","volume":"18","author":"Wang","year":"2007","journal-title":"Meas. Sci. Technol."},{"key":"ref_110","doi-asserted-by":"crossref","first-page":"1828","DOI":"10.1109\/LPT.2009.2034620","article-title":"Relative humidity sensor based on cascaded long-period gratings with hydrogel coatings and fourier demodulation","volume":"21","author":"Yu","year":"2009","journal-title":"Photonics Technol. Lett. IEEE"},{"key":"ref_111","doi-asserted-by":"crossref","first-page":"767","DOI":"10.1109\/JSEN.2012.2227714","article-title":"Analysis of polyimide-coated optical fiber long-period grating-based relative humidity sensor","volume":"13","author":"Alwis","year":"2013","journal-title":"IEEE Sens. J."},{"key":"ref_112","doi-asserted-by":"crossref","first-page":"57","DOI":"10.1016\/j.sna.2008.07.015","article-title":"Long period grating-based humidity sensor for potential structural health monitoring","volume":"148","author":"Venugopalan","year":"2008","journal-title":"Sens. Actuators A Phys."},{"key":"ref_113","doi-asserted-by":"crossref","first-page":"519","DOI":"10.3390\/s90100519","article-title":"Sensitivity improvement of a humidity sensor based on silica nanospheres on a long-period fiber grating","volume":"9","author":"Viegas","year":"2009","journal-title":"Sensors"},{"key":"ref_114","doi-asserted-by":"crossref","first-page":"1632","DOI":"10.1109\/JSEN.2013.2238229","article-title":"Fiber optic hybrid device for simultaneous measurement of humidity and temperature","volume":"13","author":"Mathew","year":"2013","journal-title":"IEEE Sens. J."},{"key":"ref_115","unstructured":"Marcuse, D. (1991). Theory of Dielectric Optical Waveguides, Academic Press. [2nd ed.]."},{"key":"ref_116","doi-asserted-by":"crossref","first-page":"569","DOI":"10.1016\/j.snb.2012.10.009","article-title":"Electrospun nanofiber mats for evanescent optical fiber sensors","volume":"176","author":"Urrutia","year":"2013","journal-title":"Sens. Actuators B Chem."},{"key":"ref_117","doi-asserted-by":"crossref","first-page":"2164","DOI":"10.1364\/AO.51.002164","article-title":"Titanium dioxide nanoparticle based optical fiber humidity sensor with linear response and enhanced sensitivity","volume":"51","author":"Aneesh","year":"2012","journal-title":"Appl. Opt."},{"key":"ref_118","doi-asserted-by":"crossref","first-page":"1340","DOI":"10.1016\/j.snb.2011.09.072","article-title":"A low cost fiber-optic humidity sensor based on silica sol-gel film","volume":"160","author":"Zhao","year":"2011","journal-title":"Sens. Actuators B Chem."},{"key":"ref_119","doi-asserted-by":"crossref","first-page":"385","DOI":"10.1016\/j.snb.2010.03.049","article-title":"A humidity sensor based on a hetero-core optical fiber","volume":"147","author":"Akita","year":"2010","journal-title":"Sens. Actuators B Chem."},{"key":"ref_120","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.sna.2012.10.041","article-title":"Novel optical fiber humidity sensor based on a no-core fiber structure","volume":"190","author":"Xia","year":"2013","journal-title":"Sens. Actuators A Phys."},{"key":"ref_121","unstructured":"Zhao, Y., Jin, Y., and Liang, H. (2011, January 29\u201331). All-Fiber-Optic Sensor for Relative Humidity Measurement. Dalian, China."},{"key":"ref_122","doi-asserted-by":"crossref","first-page":"320","DOI":"10.1016\/j.talanta.2009.12.003","article-title":"Effect of particle size variation of Ag nanoparticles in Polyaniline composite on humidity sensing","volume":"81","author":"Fuke","year":"2010","journal-title":"Talanta"},{"key":"ref_123","doi-asserted-by":"crossref","first-page":"19404","DOI":"10.1364\/OE.20.019404","article-title":"Growth of well-arrayed ZnO nanorods on thinned silica fiber and application for humidity sensing","volume":"20","author":"Liu","year":"2012","journal-title":"Opt. Express"},{"key":"ref_124","doi-asserted-by":"crossref","first-page":"322","DOI":"10.1109\/JSEN.2004.827274","article-title":"Optical-fiber sensor using tailored porous sol-gel fiber core","volume":"4","author":"Tao","year":"2004","journal-title":"IEEE Sens. J."},{"key":"ref_125","doi-asserted-by":"crossref","first-page":"409","DOI":"10.1109\/JSEN.2006.890129","article-title":"Agarose-gel based guided-mode resonance humidity sensor","volume":"7","author":"Lee","year":"2007","journal-title":"IEEE Sens. J."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/3\/3986\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:08:38Z","timestamp":1760216918000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/14\/3\/3986"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2014,2,26]]},"references-count":125,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2014,3]]}},"alternative-id":["s140303986"],"URL":"https:\/\/doi.org\/10.3390\/s140303986","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2014,2,26]]}}}