This paper discusses the current technical limitations posed on endeavors to miniaturize lidar systems for use in automotive applications and how to possibly extend those limits. The focus is set on long-range scanning direct time of flight LiDAR systems using APD photodetectors. Miniaturization evokes severe problems in ensuring absolute laser safety while maintaining the systems' performance in terms of maximum range, signal-to-noise ratio, detection probability, pixel density, or frame rate. Based on hypothetical but realistic specifications for an exemplary system the complete lidar signal path is calculated. The maximum range of the system is used as a general performance indicator. It is determined with the minimum signal-to-noise ratio required to detect an object. Various system parameters are varied to find their impact on the system's range. The reduction of the laser's pulse width and the right choice for the transimpedance amplifier's amplification have shown to be practicable measures to double the system's range.

Date Published: 10 May 2017
PDF: 12 pages
Proc. SPIE 10219, Three-Dimensional Imaging, Visualization, and Display 2017, 102190T (10 May 2017); doi: 10.1117/12.2260894

Published in SPIE Proceedings Vol. 10219:
Three-Dimensional Imaging, Visualization, and Display 2017
Bahram Javidi; Jung-Young Son; Osamu Matoba, Editor(s)