{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:17:09Z","timestamp":1760145429510,"version":"build-2065373602"},"reference-count":16,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2024,7,14]],"date-time":"2024-07-14T00:00:00Z","timestamp":1720915200000},"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>The seawater refractive index is an essential parameter in ocean observation, making its high-precision measurement necessary. This can be effectively achieved using a position-sensitive detector-based measurement system. However, in the actual measurement process, the impact of the jitter signal measurement error on the results cannot be ignored. In this study, we theoretically analysed the causes of long jitter signals during seawater refractive index measurements and quantified the influencing factors. Through this analysis, it can be seen that the angle between the two windows in the seawater refractive index measurement area caused a large error in the results, which could be effectively reduced by controlling the angle to within 2.06\u00b0. At the same time, the factors affecting the position-sensitive detector\u2019s measurement accuracy were analysed, with changes to the background light, the photosensitive surface\u2019s size, and the working environment\u2019s temperature leading to its reduction. To address the above factors, we first added a 0.9 nm bandwidth, narrow-band filter in front of the detector\u2019s photosensitive surface during system construction to filter out any light other than that from the signal light source. To ensure the seawater refractive index\u2019s measuring range, a position-sensitive detector with a photosensitive surface size of 4 mm \u00d7 4 mm was selected; whereas, to reduce the working environment\u2019s temperature variation, we partitioned the measurement system. To validate the testing error range of the optimised test system, standard seawater samples were measured under the same conditions, showing a reduction in the measurement system\u2019s jitter signal from 0.0022 mm to 0.0011 mm, before and after optimisation, respectively, as well as a reduction in the refractive index\u2019s deviation. The experimental results show that the refractive index of seawater was effectively reduced by adjusting the measurement system\u2019s optical path and structure.<\/jats:p>","DOI":"10.3390\/s24144564","type":"journal-article","created":{"date-parts":[[2024,7,15]],"date-time":"2024-07-15T14:15:49Z","timestamp":1721052949000},"page":"4564","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Measurement Error Analysis of Seawater Refractive Index: A Measurement Sensor Based on a Position-Sensitive Detector"],"prefix":"10.3390","volume":"24","author":[{"given":"Guanlong","family":"Zhou","sequence":"first","affiliation":[{"name":"School of Physics, Changchun University of Science and Technology, Changchun 130022, China"},{"name":"Optoelectronics System Laboratory, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4295-4614","authenticated-orcid":false,"given":"Liyan","family":"Li","sequence":"additional","affiliation":[{"name":"Optoelectronics System Laboratory, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yan","family":"Zhou","sequence":"additional","affiliation":[{"name":"Optoelectronics System Laboratory, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xinyu","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Physics, Changchun University of Science and Technology, Changchun 130022, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,7,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4001","DOI":"10.1002\/grl.50785","article-title":"Tsunami speed variations in density-stratified compressible global oceans","volume":"40","author":"Watada","year":"2013","journal-title":"Geophys. Res. Lett."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"66","DOI":"10.1016\/j.oceaneng.2017.07.047","article-title":"Dynamic modeling and motion control strategy for deep-sea hybrid-driven underwater gliders considering hull deformation and seawater density variation","volume":"143","author":"Yang","year":"2017","journal-title":"Ocean Eng."},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Zhang, S.W., Li, L.Y., Liu, Y.L., and Zhou, Y. (2023). Drift Error Compensation Algorithm for Heterodyne Optical Seawater Refractive Index Monitoring of Unstable Signals. Sensors, 23.","DOI":"10.3390\/s23208460"},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"853","DOI":"10.4319\/lom.2012.10.853","article-title":"Limnological Applications of the Thermodynamic Equation of Seawater 2010 (TEOS-10)","volume":"10","author":"Pawlowicz","year":"2012","journal-title":"Limnol. Oceanogr. Methods"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"1117","DOI":"10.1175\/JTECH2016.1","article-title":"Sensor Corrections for Sea-Bird SBE-41 CP and SBE-41 CTDs","volume":"24","author":"Johnson","year":"2007","journal-title":"J. Atmos. Ocean. Technol."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/j.dsr.2009.10.001","article-title":"Practical versus absolute salinity measurements: New advances in high performance seawater salinity sensors","volume":"57","author":"Grosso","year":"2010","journal-title":"Deep Res. Part I Oceanogr. Res. Pap."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"115202","DOI":"10.1088\/0957-0233\/22\/11\/115202","article-title":"Advances in measuring ocean salinity with an optical sensor","volume":"22","author":"Grosso","year":"2011","journal-title":"Meas. Sci. Technol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1334","DOI":"10.1109\/JLT.2003.811318","article-title":"Monitoring technology of salinity in water with optical fiber sensor","volume":"21","author":"Zhao","year":"2003","journal-title":"J. Light. Technol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"015204","DOI":"10.1088\/0957-0233\/20\/1\/015204","article-title":"High-resolution and compact refractometer for salinity measurements","volume":"20","author":"Wu","year":"2009","journal-title":"Meas. Sci. Technol."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Zhou, G.L., Li, L.Y., Zhou, Y., and Chen, X.Y. (2024). High-Sensitivity Seawater Refraction Index Optical Measurement Sensor Based on a Position-Sensitive Detector. Sensors, 24.","DOI":"10.20944\/preprints202402.0398.v1"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"211","DOI":"10.1049\/iet-opt:20060107","article-title":"Nonlinearity and frequency-path modelling of three-longitudinal-mode nanometric displacement measurement system","volume":"1","author":"Olyaee","year":"2007","journal-title":"IET Optoelectron."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1016\/S0030-3992(00)00071-2","article-title":"Linearity in output signal of optical position-sensing detector systems","volume":"32","author":"Golnabi","year":"2000","journal-title":"Opt. Laser Technol."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"108844","DOI":"10.1016\/j.apradiso.2019.108844","article-title":"Study of a novel density well-logging tool using A position-sensitive detector","volume":"154","author":"Niu","year":"2019","journal-title":"Appl. Radiat. Isot."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"933","DOI":"10.1364\/AO.479307","article-title":"3D error calibration of spatial spots based on dual position-sensitive detectors","volume":"62","author":"Cheng","year":"2023","journal-title":"Appl. Opt."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"271","DOI":"10.1016\/j.measurement.2017.07.038","article-title":"FPGA based self-vibration compensated two dimensional non-contact vibration measurement using 2D position sensitive detector with remote monitoring","volume":"111","author":"Saha","year":"2017","journal-title":"Measurement"},{"key":"ref_16","unstructured":"Burton, R.A. (1951). The Application of Schlieren Photography in Fluid Flow and Heat Transfer Analysis. [Ph.D. Thesis, University of Texas]."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/14\/4564\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T15:16:46Z","timestamp":1760109406000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/24\/14\/4564"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2024,7,14]]},"references-count":16,"journal-issue":{"issue":"14","published-online":{"date-parts":[[2024,7]]}},"alternative-id":["s24144564"],"URL":"https:\/\/doi.org\/10.3390\/s24144564","relation":{},"ISSN":["1424-8220"],"issn-type":[{"type":"electronic","value":"1424-8220"}],"subject":[],"published":{"date-parts":[[2024,7,14]]}}}