A Study of Optical Design of Automotive Lighting System with Laser Source

Abstract

This study proposed a headlight for modern cars that uses lasers as a light source with optical fibers and employed a free-form surface for the optical design. A laser light source has advantages over light-emitting diodes (LEDs), a widely adopted light source on the market, in various aspects such as the emission of polarized light and a high luminous efficiency. However, regarding their application in headlights, lasers have the same weaknesses as do LED lights. They can be overheated when placed too close to engines or when in use for long durations, which causes the components to deteriorate quickly. Furthermore, the complexity of the optical design grew significantly from various problems involving laser light sources. Therefore, this study capitalized on the total internal reflection of optical fibers and located the laser light source to a position to better dissipate heat. An aspherical lens was used to facilitate the uniform distribution of the laser light. Finally, a free-form surface was incorporated into the light distribution design of the headlight. This pioneering optical design was aimed at improving luminous efficiency and reducing the complexity of the optical design. Furthermore, the white-red-green-blue laser light source was made adjustable by users to different color temperatures suitable for the ambient environment, with which the headlight provides various functions, such as changing the color temperature according to different weather conditions and operating as a fog light.