{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T10:29:22Z","timestamp":1775816962204,"version":"3.50.1"},"reference-count":31,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2023,1,28]],"date-time":"2023-01-28T00:00:00Z","timestamp":1674864000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62005273"],"award-info":[{"award-number":["62005273"]}]},{"name":"National Natural Science Foundation of China","award":["ZR2020QF100"],"award-info":[{"award-number":["ZR2020QF100"]}]},{"name":"National Natural Science Foundation of China","award":["12133009"],"award-info":[{"award-number":["12133009"]}]},{"name":"Shandong Province Natural Science Foundation of China","award":["62005273"],"award-info":[{"award-number":["62005273"]}]},{"name":"Shandong Province Natural Science Foundation of China","award":["ZR2020QF100"],"award-info":[{"award-number":["ZR2020QF100"]}]},{"name":"Shandong Province Natural Science Foundation of China","award":["12133009"],"award-info":[{"award-number":["12133009"]}]},{"name":"Research on accuracy improvement mechanism and path of heavy load six degree of freedom adjustment platform for Large Digital Survey Telescope","award":["62005273"],"award-info":[{"award-number":["62005273"]}]},{"name":"Research on accuracy improvement mechanism and path of heavy load six degree of freedom adjustment platform for Large Digital Survey Telescope","award":["ZR2020QF100"],"award-info":[{"award-number":["ZR2020QF100"]}]},{"name":"Research on accuracy improvement mechanism and path of heavy load six degree of freedom adjustment platform for Large Digital Survey Telescope","award":["12133009"],"award-info":[{"award-number":["12133009"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>A new sensor type is proposed to accurately detect the surface profiles of three-dimensional (3D) free-form surfaces. This sensor is based on the single-exposure, zero-crossing method and is used to measure position and angle simultaneously. First, the field intensity distribution in the posterior focal plane of the confocal microscope\u2019s objective was modeled accurately. Second, because the camera needs to trigger acquisition when the surface (to be measured) reaches the focal position of the sensor, a zero-crossing prediction method based on a sliding window was proposed. Third, a fast, spatially convergent, peak-extraction algorithm was proposed to improve the accuracy and efficiency of peak extraction. This scheme reduces system installation and adjustment difficulties, and the single-exposure, zero-crossing method achieves high-speed, real-time image acquisitions. The experimental results indicate that the average error of the zero-crossing prediction system was 17.63 nm, the average error of the tilt degree measurement was 0.011\u00b0 in the range of 0\u20138\u00b0, and the prediction error of the tilt direction measurement was 0.089\u00b0 in the range of 0\u2013360\u00b0. The sensor can measure the slope and can be potentially used for 3D surface precision detection.<\/jats:p>","DOI":"10.3390\/s23031453","type":"journal-article","created":{"date-parts":[[2023,1,30]],"date-time":"2023-01-30T02:01:18Z","timestamp":1675044078000},"page":"1453","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":8,"title":["A Differential Confocal Sensor for Simultaneous Position and Slope Acquisitions Based on a Zero-Crossing Prediction Algorithm"],"prefix":"10.3390","volume":"23","author":[{"given":"Tingyu","family":"Wang","sequence":"first","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China"},{"name":"College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Jilin Provincial Key Laboratory of Intelligent Wavefront Sensing and Control, Changchun 130033, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7281-5722","authenticated-orcid":false,"given":"Zhiyi","family":"Wang","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China"},{"name":"College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Jilin Provincial Key Laboratory of Intelligent Wavefront Sensing and Control, Changchun 130033, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yongqiang","family":"Yang","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China"},{"name":"College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Xiaotao","family":"Mi","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China"},{"name":"College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yunzan","family":"Ti","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China"},{"name":"College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jianli","family":"Wang","sequence":"additional","affiliation":[{"name":"Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China"},{"name":"College of Materials Science and Opto-Electronic Technology, University of Chinese Academy of Sciences, Beijing 100049, China"},{"name":"Jilin Provincial Key Laboratory of Intelligent Wavefront Sensing and Control, Changchun 130033, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,1,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"e17026","DOI":"10.1038\/lsa.2017.26","article-title":"Freeform spectrometer enabling increased compactness","volume":"6","author":"Reimers","year":"2017","journal-title":"Light Sci. 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