Tiny LiDAR module targets drones

September 21, 2016 // By Julien Happich
A provider of QuantumFilm camera sensors, startup InVisage Technologies has launched the Spark Micro-LiDAR (SML20) module with a range of 20 metres.

Measuring onyl 8.5x8.5x4.5mm, the unit is built around the company's Spark4K 13-megapixel, 1.1-micron NIR sensor which enables the SML20 module to sense structured light patterns with high acuity at a range of 20 meters, even in direct sunlight. The ultra-light, compact, and low power LiDAR supports self-navigating and collision-avoidance features for drones and other mobile autonomous devices.

Drawing between 200 and 500mW on average, depending on the range requirements of the application, the single camera-based obstacle avoidance system uses structured light to map its environments in 3D. Pairing Spark NIR sensors with lasers emitting a specific pattern of light, depth maps are captured by detecting modifications to that pattern. SML20 delivers QuantumFilm’s increased sensitivity to 940-nanometer NIR light (five times that of silicon) at a 1.1-micron pixel size. This allows autonomous devices to perceive their surroundings with an accurate depth map fused with the sharpness of 4K 30fps video previously reserved for cinema cameras, in contrast to the limited information in the series of dotted outlines offered by LiDAR.

Optimized for the invisible NIR 940-nanometre wavelength, SML20 takes advantage of the fact that water in the atmosphere absorbs most of the 940-nanometre infrared light in sunlight, minimizing solar interference with the structured light patterns. In combination with this wavelength optimization, SML20’s 1.1-micron pixels have a global electronic shutter, allowing all parts of an image to be captured simultaneously and eliminating the distortion of fast-moving objects caused by conventional rolling shutter. With global shutter, a structured light source can be pulsed in sync with an ultra-fast exposure, allowing for 20-metre ranging with high solar irradiance rejection while remaining eye-safe and low power. The company is planning further range options at 100 metres and beyond in the coming quarters.

Visit InVisage Technologies at www.invisage.com