{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,28]],"date-time":"2026-04-28T08:08:07Z","timestamp":1777363687751,"version":"3.51.4"},"reference-count":31,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,1,11]],"date-time":"2021-01-11T00:00:00Z","timestamp":1610323200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>This paper presents a high-linearity high-resolution time-of-flight (ToF) linear-array digital image sensor using a time-domain negative feedback technique. A coarse ToF measurement loop uses a 5-bit digital-to-time converter (DTC) and a delayed gating-pulse generator for time-domain feedback to find the zero of the difference between ToF and the digital estimate of the gating-pulse delay while maintaining a constant operating point of the analog readout circuits. A fine ToF measurement uses a delta-sigma modulation (DSM) loop using the time-domain feedback with a bit-stream signal form. Because of the self-contained property of the DSM for low distortion and noise exploited by the oversampling signal processing, the proposed technique provides high-linearity and high-range resolution in the fine ToF measurement. A prototype ToF sensor of 16.8 \u00d7 16.8 \u03bcm2 two-tap pixels and fabricated in a 0.11 \u03bcm (1P4M) CMOS image sensors (CIS) process achieves +0.9%\/\u22120.47% maximum nonlinearity error and a resolution of 0.24 mm (median) for the measurement range of 0\u20131.05 m. The ToF sensor produces an 11-bit fully digital output with a ToF measurement time of 22.4 ms.<\/jats:p>","DOI":"10.3390\/s21020454","type":"journal-article","created":{"date-parts":[[2021,1,11]],"date-time":"2021-01-11T11:36:11Z","timestamp":1610364971000},"page":"454","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["High-Linearity High-Resolution Time-of-Flight Linear-Array Digital Image Sensor Using Time-Domain Feedback"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7489-8082","authenticated-orcid":false,"given":"Juyeong","family":"Kim","sequence":"first","affiliation":[{"name":"Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8011, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keita","family":"Yasutomi","sequence":"additional","affiliation":[{"name":"Research Institute of Electronics, Shizuoka University, Hamamatsu, Shizuoka 432-8011, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Keiichiro","family":"Kagawa","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8011, Japan"},{"name":"Research Institute of Electronics, Shizuoka University, Hamamatsu, Shizuoka 432-8011, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shoji","family":"Kawahito","sequence":"additional","affiliation":[{"name":"Graduate School of Science and Technology, Shizuoka University, Hamamatsu, Shizuoka 432-8011, Japan"},{"name":"Research Institute of Electronics, Shizuoka University, Hamamatsu, Shizuoka 432-8011, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,1,11]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Shcherbakova, O., Pancheri, L., Dalla Betta, G.F., Massari, N., and Stoppa, D. 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