Modern vehicle lighting systems are intended to improve safety on the road by providing the adequate visibility to the drivers under different driving conditions from within a compact housing. Using a high-power semipolar GaN-based blue laser diode (>3W) that pumps a yellow phosphor in a remote position, BMW and SLD co-developed a new high-luminance white point-like source having a peak brightness of over 1000 cd/mm², which is 10 times than that of high-power white LEDs. This results in extending the range of the visibility to the maximum regulatory photometric values (~600m) and in enhancing the contrast of different light distributions in the far-field. New lighting functions, devoted to guiding, assistance and communication, for example between self-driving vehicles and pedestrians, require variable, free patterned light distributions that are clearly perceivable by the driver and/or pedestrians. One way to achieve them is through the use of high-luminance, dynamic light sources with a higher luminous flux and a higher “automotive” lifetime. Such sources should enable a relatively high resolution in the far-field. Multiple efficient, high-power semi-polar blue laser emitters have therefore to be integrated in a thermo-optically stable package. Different patterns are generated on an optimized structured phosphor that is excited by a moving blue laser spot. This dynamic is enabled by a robust, compact, fast beam steering MEMS mirror. The pattern is projected in the far-field using a customized secondary optical system. Eye safety measures that ensure a safe usage in the vehicle and in the manufacturing sites, have to be implemented in such sources.
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