{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,12]],"date-time":"2026-06-12T07:33:07Z","timestamp":1781249587510,"version":"3.54.1"},"reference-count":38,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2023,6,4]],"date-time":"2023-06-04T00:00:00Z","timestamp":1685836800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100000266","name":"EPSRC Network Plus in Digitalised Surface Manufacturing: Towards \u201cWorld\u2019s Best\u201d Processes","doi-asserted-by":"publisher","award":["EP\/S036180\/1"],"award-info":[{"award-number":["EP\/S036180\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000266","name":"EPSRC Network Plus in Digitalised Surface Manufacturing: Towards \u201cWorld\u2019s Best\u201d Processes","doi-asserted-by":"publisher","award":["EP\/T024607\/1"],"award-info":[{"award-number":["EP\/T024607\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000266","name":"EPSRC Network Plus in Digitalised Surface Manufacturing: Towards \u201cWorld\u2019s Best\u201d Processes","doi-asserted-by":"publisher","award":["1059795"],"award-info":[{"award-number":["1059795"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000266","name":"EPSRC Intelligent engineering coatings for in-manufacture and in-service monitoring of critical safety products (CoatIN)","doi-asserted-by":"publisher","award":["EP\/S036180\/1"],"award-info":[{"award-number":["EP\/S036180\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000266","name":"EPSRC Intelligent engineering coatings for in-manufacture and in-service monitoring of critical safety products (CoatIN)","doi-asserted-by":"publisher","award":["EP\/T024607\/1"],"award-info":[{"award-number":["EP\/T024607\/1"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100000266","name":"EPSRC Intelligent engineering coatings for in-manufacture and in-service monitoring of critical safety products (CoatIN)","doi-asserted-by":"publisher","award":["1059795"],"award-info":[{"award-number":["1059795"]}],"id":[{"id":"10.13039\/501100000266","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013704","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT\u2014M\u00e9xico)","doi-asserted-by":"publisher","award":["EP\/S036180\/1"],"award-info":[{"award-number":["EP\/S036180\/1"]}],"id":[{"id":"10.13039\/501100013704","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013704","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT\u2014M\u00e9xico)","doi-asserted-by":"publisher","award":["EP\/T024607\/1"],"award-info":[{"award-number":["EP\/T024607\/1"]}],"id":[{"id":"10.13039\/501100013704","id-type":"DOI","asserted-by":"publisher"}]},{"DOI":"10.13039\/501100013704","name":"Consejo Nacional de Ciencia y Tecnolog\u00eda (CONACYT\u2014M\u00e9xico)","doi-asserted-by":"publisher","award":["1059795"],"award-info":[{"award-number":["1059795"]}],"id":[{"id":"10.13039\/501100013704","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The requirement for alternatives in roll-to-roll (R2R) processing to expand thin film inspection in wider substrates at lower costs and reduced dimensions, and the need to enable newer control feedback options for these types of processes, represents an opportunity to explore the applicability of newer reduced-size spectrometers sensors. This paper presents the hardware and software development of a novel low-cost spectroscopic reflectance system using two state-of-the-art sensors for thin film thickness measurements. The parameters to enable the thin film measurements using the proposed system are the light intensity for two LEDs, the microprocessor integration time for both sensors and the distance from the thin film standard to the device light channel slit for reflectance calculations. The proposed system can deliver better-fit errors compared with a HAL\/DEUT light source using two methods: curve fitting and interference interval. By enabling the curve fitting method, the lowest root mean squared error (RMSE) obtained for the best combination of components was 0.022 and the lowest normalised mean squared error (MSE) was 0.054. The interference interval method showed an error of 0.09 when comparing the measured with the expected modelled value. The proof of concept in this research work enables the expansion of multi-sensor arrays for thin film thickness measurements and the potential application in moving environments.<\/jats:p>","DOI":"10.3390\/s23115326","type":"journal-article","created":{"date-parts":[[2023,6,5]],"date-time":"2023-06-05T02:57:47Z","timestamp":1685933867000},"page":"5326","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["A Spectroscopic Reflectance-Based Low-Cost Thickness Measurement System for Thin Films: Development and Testing"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-3251-4116","authenticated-orcid":false,"given":"N\u00e9stor Eduardo","family":"S\u00e1nchez-Arriaga","sequence":"first","affiliation":[{"name":"Amy Johnson Building, Department of Automatic Control and Systems Engineering, University of Sheffield, Portobello St., Sheffield S1 3JD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Divya","family":"Tiwari","sequence":"additional","affiliation":[{"name":"Amy Johnson Building, Department of Automatic Control and Systems Engineering, University of Sheffield, Portobello St., Sheffield S1 3JD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Windo","family":"Hutabarat","sequence":"additional","affiliation":[{"name":"Amy Johnson Building, Department of Automatic Control and Systems Engineering, University of Sheffield, Portobello St., Sheffield S1 3JD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Adrian","family":"Leyland","sequence":"additional","affiliation":[{"name":"Sir Robert Hadfield Building, Department of Materials Science and Engineering, University of Sheffield, Mappin St., Sheffield S1 3JD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ashutosh","family":"Tiwari","sequence":"additional","affiliation":[{"name":"Amy Johnson Building, Department of Automatic Control and Systems Engineering, University of Sheffield, Portobello St., Sheffield S1 3JD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,4]]},"reference":[{"key":"ref_1","unstructured":"Data Bridge Market Research (2021, July 11). 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