On the calibration of a SPAD-based 3D imager with in-pixel TDC using a time-gated technique

Description

The optical characterization of a CMOS 64×64 single-photon avalanche-diode (SPAD) array with in-pixel 11b time-to-digital converter (TDC) is presented. The overall full-width half-maximum (FWHM) of the detector ensemble SPAD plus TDC is 690ps. The sensor has been fabricated in a 0.18μm standard CMOS technology which features an average dark-count rate (DCR) of 42kHz at 1V excess voltage (V e ) and room temperature. The detector successfully uses its time-gating capability to mitigate this large amount of noise enabling the sensor for accurate time-of-flight (ToF) measurements. The effectiveness of the time-gating technique is experimentally demonstrated. According to measurements, a time window of 400ns is enough to ensure that the TDC is triggered by light rather than by spurious events.

Abstract

Office of Naval Research (USA) N000141410355

Abstract

Ministerio de Economía y Competitividad TEC2012-38921- C02, IPT- 2011-1625-430000, IPC- 20111009

Abstract

Junta de Andalucía TIC 2012- 2338

Additional details