Reseach Of Semiconductor Laser White Light Souces Which Is Used In Car Headlight

Semiconductor laser is a kind of light source with long working life, small size and stable performance, it has a high electro-optical conversion efficiency also, A car head-light which is made of semiconductor laser has many advantages, such as low power consumption, small size, long working life and so on. Laser headlight is a choice for the next generation of head-light. Laser white light source is the most important part of head-lights. Germany’s BMW has launched a study on the laser head-light years ago. However,there was no company studied it in our country. So it is meaningful to research it.To get the white light source, phosphors was excited by blue laser(450 nm). There are two way, one is yellow phosphors excited by blue laser. The other one is yellow phosphor and the red phosphors were excited by blue laser at the same time. Paper concluded that the white light sources can be achieved while yellow phosphor and red phosphor were excited by blue laser.1. Laser is one of light sources with characteristics of high energy density, The effect of different concentrations of the fluorescent to the laser white light source was studied. A good quality white light source is obtained while the thick of phosphors was 1.6 mm and the content of phosphor was 16.7%.2. The relationship between red phosphor and color rendering index was researched also. the color rendering index increased from 61.2 to 69.3 after red phosphors were added in the Silicone.3. The effects of incident angle and polarization property of the laser on the excited white light luminous flux were investigated theoretically.. The optimal angle of incidence is 56 °. The reflectance of blue laser was the least while the incident angle was 56°, and enhancing the efficiency blue thereby.4. One kind of optical software was used to simulation the results when phosphors were encapsulated on transparent glass or mirror. And the Color uniformity of light source was tested also.The light flux of the laser white light source which was packaged on glass was 117.5 lm. The light flux of the laser white light source which was packaged on mirror was 109.0 lm. Reflector can improve light source’s color uniformity.5. Two style of laser white light sources were product, the one with big volume, the other one with small volume. The big one’s flux is 99.7 lm. Compared with the other light source, the small volume laser white light source is better. The small volume laser white light’s light intensity distribution was measured by a near-field optical measurement system. The color temperature distribution of laser white light source was researched, and the color coordinates were studied also. In order to test the availability of laser white light sources, a spotlights and headlight were designed.