{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,10]],"date-time":"2026-01-10T02:40:20Z","timestamp":1768012820556,"version":"3.49.0"},"reference-count":20,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2021,1,20]],"date-time":"2021-01-20T00:00:00Z","timestamp":1611100800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Ministry of Science and Technology","award":["MOST 108-2221-E-011-144-MY2"],"award-info":[{"award-number":["MOST 108-2221-E-011-144-MY2"]}]},{"name":"Ministry of Science and Technology","award":["MOST 109-2627-M-002-001"],"award-info":[{"award-number":["MOST 109-2627-M-002-001"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This study aimed to develop an automated optical inspection (AOI) system that can rapidly and precisely measure the dimensions of microchannels embedded inside a transparent polymeric substrate, and can eventually be used on the production line of a factory. The AOI system is constructed based on Snell\u2019s law. The concept holds that, when light travels through two transparent media (air and the microfluidic chip transparent material), by capturing the parallel refracted light from a light source that went through the microchannel using a camera with a telecentric lens, the image can be analyzed using formulas derived from Snell\u2019s law to measure the dimensions of the microchannel cross-section. Through the NI LabVIEW 2018 SP1 programming interface, we programmed this system to automatically analyze the captured image and acquire all the needed data. The system then processes these data using custom-developed formulas to calculate the height and width measurements of the microchannel cross-sections and presents the results on the human\u2013machine interface (HMI). In this study, a single and straight microchannel with a cross-sectional area of 300 \u03bcm \u00d7 300 \u03bcm and length of 44 mm was micromachined and sealed with another polymeric substrate by a solvent bonding method for experimentations. With this system, 45 cross-sectional areas along the straight microchannel were measured within 20 s, and experiment results showed that the average measured error was less than 2%.<\/jats:p>","DOI":"10.3390\/s21030698","type":"journal-article","created":{"date-parts":[[2021,1,21]],"date-time":"2021-01-21T00:53:41Z","timestamp":1611190421000},"page":"698","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Development of an Automated Optical Inspection System for Rapidly and Precisely Measuring Dimensions of Embedded Microchannel Structures in Transparent Bonded Chips"],"prefix":"10.3390","volume":"21","author":[{"given":"Pin-Chuan","family":"Chen","sequence":"first","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan"},{"name":"High Speed 3D Printing Research Center, National Taiwan University of Science and Technology, Taipei 106, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ya-Ting","family":"Lin","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-6884-474X","authenticated-orcid":false,"given":"Chi-Minh","family":"Truong","sequence":"additional","affiliation":[{"name":"Department of Mechanical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Pai-Shan","family":"Chen","sequence":"additional","affiliation":[{"name":"Graduate Institute of Toxicology, College of Medicine, National Taiwan University, Taipei 100, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huihua-Kenny","family":"Chiang","sequence":"additional","affiliation":[{"name":"Institute of Biomedical Engineering, National Yang-Ming University, Taipei 112, Taiwan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,20]]},"reference":[{"key":"ref_1","unstructured":"(2019, May 06). 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