{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,14]],"date-time":"2026-02-14T00:37:03Z","timestamp":1771029423341,"version":"3.50.1"},"reference-count":18,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2022,1,13]],"date-time":"2022-01-13T00:00:00Z","timestamp":1642032000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/100018539","name":"Institut Mines-T\u00e9l\u00e9com","doi-asserted-by":"publisher","award":["Futur & Ruptures"],"award-info":[{"award-number":["Futur & Ruptures"]}],"id":[{"id":"10.13039\/100018539","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>We present the design, fabrication, and test of a multipurpose integrated circuit (Application Specific Integrated Circuit) in AMS 0.35 \u00b5m Complementary Metal Oxide Semiconductor technology. This circuit is embedded in a scleral contact lens, combined with photodiodes enabling the gaze direction detection when illuminated and wirelessly powered by an eyewear. The gaze direction is determined by means of a centroid computation from the measured photocurrents. The ASIC is used simultaneously to detect specific eye blinking sequences to validate target designations, for instance. Experimental measurements and validation are performed on a scleral contact lens prototype integrating four infrared photodiodes, mounted on a mock-up eyeball, and combined with an artificial eyelid. The eye-tracker has an accuracy of 0.2\u00b0, i.e., 2.5 times better than current mobile video-based eye-trackers, and is robust with respect to process variations, operating time, and supply voltage. Variations of the computed gaze direction transmitted to the eyewear, when the eyelid moves, are detected and can be interpreted as commands based on blink duration or using blinks alternation on both eyes.<\/jats:p>","DOI":"10.3390\/s22020595","type":"journal-article","created":{"date-parts":[[2022,1,14]],"date-time":"2022-01-14T03:14:03Z","timestamp":1642130043000},"page":"595","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":9,"title":["Multipurpose Bio-Monitored Integrated Circuit in a Contact Lens Eye-Tracker"],"prefix":"10.3390","volume":"22","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-5144-5884","authenticated-orcid":false,"given":"Lo\u00efc","family":"Massin","sequence":"first","affiliation":[{"name":"Optics Department, Institut Mines-T\u00e9l\u00e9com Atlantique, Technop\u00f4le Brest Iroise, CS 83818, CEDEX 03, 29238 Brest, Brittany, France"},{"name":"Laboratoire des Sciences et Techniques de l\u2019Information, de la Communication et de la Connaissance, UMR 6285, 29238 Brest, Brittany, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1316-5504","authenticated-orcid":false,"given":"Cyril","family":"Lahuec","sequence":"additional","affiliation":[{"name":"Optics Department, Institut Mines-T\u00e9l\u00e9com Atlantique, Technop\u00f4le Brest Iroise, CS 83818, CEDEX 03, 29238 Brest, Brittany, France"},{"name":"Laboratoire des Sciences et Techniques de l\u2019Information, de la Communication et de la Connaissance, UMR 6285, 29238 Brest, Brittany, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Fabrice","family":"Seguin","sequence":"additional","affiliation":[{"name":"Optics Department, Institut Mines-T\u00e9l\u00e9com Atlantique, Technop\u00f4le Brest Iroise, CS 83818, CEDEX 03, 29238 Brest, Brittany, France"},{"name":"Laboratoire des Sciences et Techniques de l\u2019Information, de la Communication et de la Connaissance, UMR 6285, 29238 Brest, Brittany, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1949-2207","authenticated-orcid":false,"given":"Vincent","family":"Nourrit","sequence":"additional","affiliation":[{"name":"Optics Department, Institut Mines-T\u00e9l\u00e9com Atlantique, Technop\u00f4le Brest Iroise, CS 83818, CEDEX 03, 29238 Brest, Brittany, France"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jean-Louis","family":"de Bougrenet de la Tocnaye","sequence":"additional","affiliation":[{"name":"Optics Department, Institut Mines-T\u00e9l\u00e9com Atlantique, Technop\u00f4le Brest Iroise, CS 83818, CEDEX 03, 29238 Brest, Brittany, France"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2022,1,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"eaap9841","DOI":"10.1126\/sciadv.aap9841","article-title":"Soft, smart contact lenses with integrations of wireless circuits, glucose sensors, and displays","volume":"4","author":"Park","year":"2018","journal-title":"Sci. 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