{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T20:54:08Z","timestamp":1768942448746,"version":"3.49.0"},"reference-count":37,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2023,9,8]],"date-time":"2023-09-08T00:00:00Z","timestamp":1694131200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Sciences and Engineering Research Council of Canada"},{"name":"Accessible Technology Program"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Technological advances in eye-tracking have resulted in lightweight, portable solutions that are capable of capturing eye movements beyond laboratory settings. Eye-tracking devices have typically relied on heavier, video-based systems to detect pupil and corneal reflections. Advances in mobile eye-tracking technology could facilitate research and its application in ecological settings; more traditional laboratory research methods are able to be modified and transferred to real-world scenarios. One recent technology, the AdHawk MindLink, introduced a novel camera-free system embedded in typical eyeglass frames. This paper evaluates the AdHawk MindLink by comparing the eye-tracking recordings with a research \u201cgold standard\u201d, the EyeLink II. By concurrently capturing data from both eyes, we compare the capability of each eye tracker to quantify metrics from fixation, saccade, and smooth pursuit tasks\u2014typical elements in eye movement research\u2014across a sample of 13 adults. The MindLink system was capable of capturing fixation stability within a radius of less than 0.5\u2218, estimating horizontal saccade amplitudes with an accuracy of 0.04\u2218\u00b1 2.3\u2218, vertical saccade amplitudes with an accuracy of 0.32\u2218\u00b1 2.3\u2218, and smooth pursuit speeds with an accuracy of 0.5 to 3\u2218s, depending on the pursuit speed. While the performance of the MindLink system in measuring fixation stability, saccade amplitude, and smooth pursuit eye movements were slightly inferior to the video-based system, MindLink provides sufficient gaze-tracking capabilities for dynamic settings and experiments.<\/jats:p>","DOI":"10.3390\/s23187753","type":"journal-article","created":{"date-parts":[[2023,9,8]],"date-time":"2023-09-08T08:01:30Z","timestamp":1694160090000},"page":"7753","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Investigation of Camera-Free Eye-Tracking Glasses Compared to a Video-Based System"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7872-7715","authenticated-orcid":false,"given":"Abdullah","family":"Zafar","sequence":"first","affiliation":[{"name":"Department of Kinesiology & Health Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0930-2913","authenticated-orcid":false,"given":"Claudia Martin","family":"Calderon","sequence":"additional","affiliation":[{"name":"Department of Kinesiology & Health Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Anne Marie","family":"Yeboah","sequence":"additional","affiliation":[{"name":"School of Optometry & Vision Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kristine","family":"Dalton","sequence":"additional","affiliation":[{"name":"School of Optometry & Vision Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Elizabeth","family":"Irving","sequence":"additional","affiliation":[{"name":"School of Optometry & Vision Science, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Ewa","family":"Niechwiej-Szwedo","sequence":"additional","affiliation":[{"name":"Department of Kinesiology & Health Sciences, University of Waterloo, Waterloo, ON N2L 3G1, Canada"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,9,8]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1007\/7854_2019_98","article-title":"Eye movements in neuropsychological tasks","volume":"41","author":"Hodgson","year":"2019","journal-title":"Curr. 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