The high luminance of laser sources attracted the attention of vehicle lighting engineers for visible-light applications and for infrared applications such as lidar.
Laser High Beam Booster
The application of laser sources in combination with remote phosphors to generate an ultra-
powerful high beam was the first use in vehicle lighting. Started in 2014 by BMW and Audi, a number of other brands have since then also adopted this technology for their premium car models—still mainly available as an option, not as standard equipment.
Ultra-thin Cavities
The effective visual impression of ultra-thin cavities has a practical lower limit at about 10-15 mm height. Several companies started production of headlamps with frontal height as little as 15 mm based on HB LED technology. Since HB LED systems are well known technology; easier and less costly to develop without need of the safety systems required by lasers, in this application, too, the use of lasers will be limited.
Scanning ADB systems
Scanning MEMS laser systems to implement ADB and road projection functionality are under heavy development by key lighting suppliers. Although the application advantages of this concept are obvious, a number of challenges still have to solved: electrical and mechanical stability of the system as well as reliability of components.
Road Projections
Presently, road projections from headlamps are mainly implemented by a separate DLP unit. A DMD mirror array is illuminated by a sophisticated optical system to generate close to homogenous illumination pattern. Light sources for this application can be HB LEDs or visible (white) laser sources. In automotive applications, mainly HB LEDs are used, here again because of their advanced state of development, low cost, and simple system architecture relative to laser setups.
Exterior Lidar Sensors
Exterior lidar sensors are strongly coupled with driving automation. In addition to cameras and radars, a third independent source of information is needed to safeguard reliable vehicle surrounding data even under adverse conditions. It is the opinion of a broad majority of automakers; tier-1 suppliers; research institutes, and industry experts that driving automation from L3 upwards needs lidar sensors for reliable functioning.
In-Cabin Sensing
Driver- and occupant monitoring systems are key technologies to observe and keep track of driver attention and occupant behaviour. Monitoring of driver attention is becoming a key element to proceed to (partial) L3 automation. Safety organisations already require in their roadmaps DMS and OMS as a feature for the best vehicle ratings, and regulators are considering are considering especially DMS as a requirement for L3+ vehicles. Additionally, OMS are being phased in to prevent death of children and pets left behind by distracted parents.
DVN REPORT: Laser technology for lighting and sensing
