Patent · US Expired

Noise reduction techniques suitable for three-dimensional information acquirable with CMOS-compatible image sensor ICS

US6522395B1 · kind B1 · utility

121Cited by
25References
16Claims
0Family size

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Key dates

Filing dateNov 28, 2000
Grant dateFeb 18, 2003
Priority date
Expiry dateNov 28, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01S7/4865
  • WIPO fieldAudio-visual technology
  • WIPO sectorElectrical engineering

Abstract

A three-dimensional imaging system is fabricated on a single IC. The system includes a two-dimensional array of pixel light sensing detectors and dedicated electronics and associated processing circuitry, all preferably fabricated on a single IC using CMOS fabrication techniques. The system includes a detector array comprising a plurality of pixel photodiodes and photodiode circuits, wherein each pixel photodiode acquires delay time data and pulse brightness data simultaneously. The system emits an energy pulse at time t0 and a fraction of the energy is returned to the array by a target object. Photodiodes in the array output a brightness signal B(t) that is integrated. An elapsed time ET from t0 to when said B(t) attains a predetermined threshold value is determined, where the slope of B(t) is B/PW, where B is B(t) after integrating over a time equal to the emitted pulse width PW. Time-of-flight TOF representing time from t0 to when a photodiode begins to detect energy is determined, where TOF=ET−IT, where IT is proportional to PW/B. A system processor determines distance from the system to the target object, from TOF and the velocity of light, and can translate TOF into com…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.