Open AccessA Submillimeter Range Resolution Time-of-Flight Range Imager With Column-Wise Skew Calibration
Author(s) -
Keita Yasutomi,
Takahiro Usui,
Sang-Man Han,
Taishi Takasawa,
Keiichiro Kagawa,
Shoji Kawahito
Publication year - 2015
Publication title -
ieee transactions on electron devices
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.828
H-Index - 186
eISSN - 1557-9646
pISSN - 0018-9383
DOI - 10.1109/ted.2015.2447525
Subject(s) - components, circuits, devices and systems , engineered materials, dielectrics and plasmas
This paper presents a time-of-flight (TOF) range imager with high-range resolution. The range imager employs a TOF measuring technique using an impulse photocurrent response and a high-speed lock-in pixel based on a drainingonly modulation. To address a skew problem in a 2-D array of the pixels, a column-wise gating-clock skew calibration was implemented. Each pixel has an in-pixel buffer and decoupling capacitor to reduce row-wise skew. A test-implemented imager has 132 × 120 effective pixels. The skew calibration circuit successfully reduce the skew from 173 to 8 psrms. The range resolution was achieved to be 0.25 mm with a 32-mm range, which corresponds to a 1.7-ps time resolution.