Laser-assisted LED for adaptive-driving-beam headlights employing ultra-reliable single crystal phosphor for autonomous vehicles

• Published in: Optics express Vol. 29; no. 17; pp. 26466 - 26473
• Main Authors: Chang, Yung-Peng, Shih, Hsing-Kun, Liu, Chun-Nien, Chen, Hsin-An, Tsai, Stark, Li, Kenneth, Han, Pin, Cheng, Wood-Hi
• Format: Journal Article
• Language: English
• Published: 16-08-2021
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.429951

A novel laser-assisted LED for adaptive-driving-beam (ADB) headlights employing an ultra-reliable Ce 3+ : YAG-based single crystal phosphor (SCP)-converter layer for use in autonomous vehicles is demonstrated. The SCP fabricated at a high-temperature of 1,940°C exhibited better thermal stability than other phosphor-converter materials, evidenced by a thermal aging test. The high-beam pattern of the ADB is measured at a luminous intensity of 88,436 cd at 0°, 69,393 cd at ± 2.5°, and 42,942 cd at ± 5°, which well satisfies the ECE R112 class B regulation. The advantage of introducing the laser-assisted LED system employing the highly reliable SCP is to produce the high intensity for the ADB, which enables the increase of the field of view by 20% and the brightness by 28% for the ADB headlight and results in improving the visibility from ± 7° to ± 8.5° and the illumination distance up to 200 m. This proposed advance ADB headlight with the ultra-reliable SCP and the novel laser-assisted LED is favorable as one of the most promising ADB light source candidates for use in the next-generation autonomous vehicle applications.