User Manual

Table Of Contents
Page 21 of 129 54A0028-6 042019 © LeddarTech Inc.
Underlying Principles
Created by LeddarTech, LEDDAR™ (light-emitting diode detection and ranging) is a unique
sensing technology based on light (infrared spectrum) and the time-of-flight of light principle. The
light source illuminates the area of interest (pulsed typically at 10 kHz for the LeddarVu8 47.5°
module) and the multichannel module receiver collects the backscatter of the emitted light and
measures the time taken for the emitted light to return back to the module.
An 8-channel photodetector array is used and provides multiple detection and ranging segments.
Full-waveform analysis enables detection and distance measurement of multiple objects in each
segment, provided that foreground objects do not fully obscure objects behind them. Oversampling
and accumulation techniques are used to provide extended resolution and range.
Figure 5 illustrates the illumination area and detection segments. In this case, the 8 segments
provide a profile of the object in the beam. In other installations, the channels can be used to locate
and track one or multiple objects in the beam.
Figure 5: Illumination area and detection zone
The core of Leddar™ sensing is the pulsing of diffused light, collection of reflected light (including
oversampling and accumulation), and full-waveform analysis. The light source type, the number of
light sources, the illumination and reception beam, and the number of photodetectors can all be
tailored to fit specific application requirements such as detection range, beam, and spatial
resolution.