Temporal and spatial focusing in SPAD-based solid-state pulsed time-of-flight laser range imaging
|Author:||Kostamovaara, Juha1; Jahromi, Sahba S.1; Keränen, Pekka1|
1Circuits and Systems Research Group, ITEE Faculty, University of Oulu, 90570 Oulu, Finland
|Online Access:||PDF Full Text (PDF, 6.7 MB)|
|Persistent link:|| http://urn.fi/urn:nbn:fi-fe2020112492761
Multidisciplinary Digital Publishing Institute,
|Publish Date:|| 2020-11-24
The relation between signal and background noise strengths in single-photon avalanche diode (SPAD)-based pulsed time-of-flight 3-D range imaging is analyzed on the assumption that the SPAD detector is operating in the single photon detection mode. Several practical measurement cases using a 256-pixel solid-state pulsed time-of-flight (TOF) line profiler are presented and analyzed in the light of the resulting analysis. It is shown that in this case it is advantageous to concentrate the available optical average power in short, intensive pulses and to focus the optical energy in spatial terms. In 3-D range imaging, this could be achieved by using block-based illumination instead of the regularly used flood illumination. One modification of this approach could be a source that would illuminate the system FOV only in narrow laser stripes. It is shown that a 256-pixel SPAD-based pulsed TOF line profiler following these design principles can achieve a measurement range of 5–10 m to non-cooperative targets at a rate of ~10 lines/s under bright sunlight conditions using an average optical power of only 260 µW.
|Type of Publication:||
A1 Journal article – refereed
|Field of Science:||
213 Electronic, automation and communications engineering, electronics
This work was supported by the Academy of Finland under Contract 317144.
|Academy of Finland Grant Number:||
317144 (Academy of Finland Funding decision)
© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).