News: Optoelectronics
4 February 2021
Osram’s new edge-emitting laser chip design matches wavelength stability of VCSELs
Light detection & ranging (LiDAR), which uses infrared light to create a precise, three-dimensional map of the environment, is a key technology in the development of autonomous vehicles (AVs). In combination with radar and camera systems, it acts as the vision of the car, capturing its surroundings. The better the visual information provided by LiDAR, the easier it is for the downstream systems to use it, notes Germany’s Osram.
Up to now, the infrared lasers used for this purpose have had deviations in wavelength stability of up to 40nm as temperature rises in the component. As a result, the LiDAR system’s ‘vision’ was a bit blurred. Osram says that it has produced a novel chip design that now reduces the wavelength shift to just 10nm, enabling much clearer and sharper images of the surroundings.
Due to the newly developed chip design, edge-emitting lasers can match and even exceed the wavelength stability of vertical-cavity surface-emitting lasers (VCSELs) at operating temperatures of up to 125°C typical for automotive applications, reckons Osram. This milestone in the development of infrared lasers allows the use of a much smaller wavelength filter on the detector, significantly improving the signal-to-noise ratio, claims the firm.
The technical advance has been demonstrated in components with triple-junctions (three light-emitting surfaces stacked one on top of the other). In the future, the new design will be used in all Osram infrared lasers, offering enormous advantages to LiDAR system manufacturers, reckons the firm.
