Quantum cascade laser LIDar Advanced Device

Public awareness of atmospheric pollution by hazardous and greenhouse gases is increasing on a global scale. As a result, demand for compact and cost-effective trace gas detection devices is also increasing. Light-based technologies are seeing many new applications owing to the rapid advancements in new sources and detectors.

This proposal is aimed at developing a new technique for light detection and ranging (LIDAR) operating with mid-IR lasers.

LIDAR is a method for detecting objects with many emerging applications in environmental control, military, robotics, autonomous systems.The use of mid-IR sources allows combining high atmospheric transparency windows with the possibility to test atmospheric pollutants in their strongest absorption bands.

In this region, quantum cascade lasers (QCLs) are of special importance, as they offer up to several watts of pulsed or cw optical power and fast internal dynamics allowing for high-frequency modulation, while retaining a good far field pattern as required for laser remote sensing techniques in atmospheric research.QuaLIDAD starts from the studies on QCLs performed within the Qombs Project and is aimed at the development of a compact LIDAR system for air multi-component chemical analysis, particulate (PM10) detection and range finding.

QuaLIDAD wants to exploit two alternative approaches, namely either the detection of backscattered light from air particulate, or the detection of reflected/scattered light by a retroreflector/obstacle.

The prototype will work in the 4-5 μm window, where water absorption is low and several important greenhouse/toxic gases (CO2, CO, N2O, ...) can be detected.

The LIDAR will be operated with the Pseudo Random Noise (PRN) technique, using fast modulation of a continuous-wave source with a specific digital pattern. This technique is better suited for QCLs and allows identifying the target distance. The in-field tests results in relevant environments will be made available to stakeholders.