{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,24]],"date-time":"2026-06-24T11:37:04Z","timestamp":1782301024293,"version":"3.54.5"},"reference-count":34,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2022,11,5]],"date-time":"2022-11-05T00:00:00Z","timestamp":1667606400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Department of Natural Resources of Guangdong Province","award":["GDNRC [2022] No. 22"],"award-info":[{"award-number":["GDNRC [2022] No. 22"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["2021A0505080002"],"award-info":[{"award-number":["2021A0505080002"]}]},{"name":"Department of Natural Resources of Guangdong Province","award":["PCL2021A14-B1"],"award-info":[{"award-number":["PCL2021A14-B1"]}]},{"name":"Guangdong Science and Technology Department","award":["GDNRC [2022] No. 22"],"award-info":[{"award-number":["GDNRC [2022] No. 22"]}]},{"name":"Guangdong Science and Technology Department","award":["2021A0505080002"],"award-info":[{"award-number":["2021A0505080002"]}]},{"name":"Guangdong Science and Technology Department","award":["PCL2021A14-B1"],"award-info":[{"award-number":["PCL2021A14-B1"]}]},{"name":"Intelligent Laser Basic Research Laboratory","award":["GDNRC [2022] No. 22"],"award-info":[{"award-number":["GDNRC [2022] No. 22"]}]},{"name":"Intelligent Laser Basic Research Laboratory","award":["2021A0505080002"],"award-info":[{"award-number":["2021A0505080002"]}]},{"name":"Intelligent Laser Basic Research Laboratory","award":["PCL2021A14-B1"],"award-info":[{"award-number":["PCL2021A14-B1"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presented a new kind of salinity and temperature dual-parameter sensor based on a fiber ring laser (FRL) with tapered side-hole fiber (SHF) embedded in a Sagnac interferometer. The sensing structure is majorly composed of tapered SHF located in the middle of SHF inside the Sagnac interferometer loop structure. The influences of the SHF\u2019s diameters of different tapered in the Sagnac interferometer loop on the FRL sensing system are studied. The presence of air holes in the SHF makes the cladding mode easier to excite, and the interaction between the cladding mode with its surroundings is enhanced, thus having higher salinity sensitivity. Besides, the unique advantages of high resolution, narrower linewidth, and high signal-to-noise ratio (SNR) of fiber laser make the measurement results more accurate. In this experiment, the SHF with different taper diameters was made, and it was found that reducing the diameter of the taper waist diameter could further improve the salinity sensitivity. When the waist diameter was 9.70 \u03bcm, the maximum salinity sensitivity of 0.2867 nm\/\u2030 was achieved. Temperature sensing experiments were also carried out. The maximum temperature sensitivity of the FRL sensing system was \u22120.3041 nm\/\u00b0C at the temperature range from 20 to 30 \u00b0C. The sensor has the characteristics of easy manufacture, good selectivity, and high sensitivity, proving the feasibility of simultaneous measurement of seawater salinity and temperature.<\/jats:p>","DOI":"10.3390\/s22218533","type":"journal-article","created":{"date-parts":[[2022,11,7]],"date-time":"2022-11-07T03:02:22Z","timestamp":1667790142000},"page":"8533","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":21,"title":["Salinity and Temperature Dual-Parameter Sensor Based on Fiber Ring Laser with Tapered Side-Hole Fiber Embedded in Sagnac Interferometer"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-8616-0659","authenticated-orcid":false,"given":"Fang","family":"Zhao","sequence":"first","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1499-2608","authenticated-orcid":false,"given":"Weihao","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"State Key Laboratory of Analog and Mixed-Signal VLSI, University of Macau, Macau 999078, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jie","family":"Hu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5933-502X","authenticated-orcid":false,"given":"Shuaiqi","family":"Liu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"State Key Laboratory of Analog and Mixed-Signal VLSI, University of Macau, Macau 999078, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3299-5594","authenticated-orcid":false,"given":"Feihong","family":"Yu","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xingwei","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Guoqing","family":"Wang","sequence":"additional","affiliation":[{"name":"School of Microelectronics, Shenzhen Institute of Information Technology, Shenzhen 518172, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1391-4736","authenticated-orcid":false,"given":"Perry Ping","family":"Shum","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1272-1959","authenticated-orcid":false,"given":"Liyang","family":"Shao","sequence":"additional","affiliation":[{"name":"Department of Electrical and Electronic Engineering, Southern University of Science and Technology, Shenzhen 518055, China"},{"name":"Peng Cheng Laboratory, Shenzhen 518005, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,11,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Cao, L., Yu, Y., Xiao, M., Yang, J., and Meng, Z. 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