Design of Digitalized Vehicle Light Illumination System Using GaN-Based Semiconductor Laser Diode

High luminance and digital controllability are the development requirements of the new generation automotive headlamps. The digital headlamp that adopts laser light sources must be pre-shaped and homogenized. Designing an efficient and compact projection lighting system is the key point of the digital laser automotive headlamp. This paper presents the design of a digital laser headlight lighting system that employs GaN-based semiconductor laser diode (LD), including collimating lens, a double-row microlens array, integrating lenses, and other optical components. LIGHTTOOLS software is used for Monte Carlo ray tracing, and the simulation results showed that the aspheric collimating lens assembly can collimate a white laser light source with a divergence half angle of 60 degrees to within 10 degrees, with most of the energy concentrated within 5 degrees. The double-row microlens arrays demonstrate a better shaping effect. The lighting system exhibits an overall illumination uniformity of up to 96%, an energy utilization of 65%, and a superior light efficiency and uniformity, and has significant implications for smart car lights in terms of perception, networking, communication, etc.