User Manual

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 Leddar Vu8 20° 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- or 16-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 cases, the

16 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.