Research On White Light Illumination System Of Semiconductor Laser Excitation Phosphor

With the growing prosperity of the optoelectronic industry,new technologies and industries such as laser headlamp lighting,interior lighting and long-distance lighting are gradually emerging.Laser white light as its key technology support has become one of the research hotspots at home and abroad.Among them,white light with good color temperature and high uniformity can be efficiently obtained,which is of great significance for practical applications.In this paper,a blue semiconductor laser after beam shaping is used to excite the YAG yellow phosphor to synthesize white light,and design and optimize free-form lens around the synthetic white light,so that the lighting target surface to form a uniform illumination and light intensity distribution.The main results are as follows:1.Semiconductor laser beam shaping is studied to obtain a semiconductor laser beam with good collimation and excitation area matched with the size of the phosphor.The method of fiber coupling is used to couple the semiconductor laser beam to obtain a uniformly symmetrical circular spot;the Zemax software is used to design and optimize a single aspherical lens to collimate the divergence angle of the coupled beam;the beam expander with kepler expander is used to expand the beam,the minimum RMS radius of the optical system is 0.929 ?m,and the required expanding effect is achieved.The collimation property and the excitation area of the blue semiconductor laser are greatly improved.2.The blue semiconductor laser after beam shaping is used to excite the phosphor,the Tracepro software is used to simulate and study the influence of phosphor molar concentration,thickness and matrix material on the central color temperature and color coordinates after the transformation.The results show that the best white center color temperature can be obtained when the molar concentration of phosphor is 129.22 mmoles/liter,and the corresponding center color temperature value is 5442 K.When the thickness is 1.001 mm,the center color temperature is 4500 K.When the thickness of the phosphor is 1 mm and the concentration is 129.0 mmole/liter,the substrate material with a refractive index of about1.6 can obtain a better white center color temperature.3.In order to make the light produced by the laser white light source can produce uniform illumination and intensity distribution on the illuminating target surface,in the interactive optimizer,the cubic spline interpolation method is used to construct and optimize the free-form lens outline,which is applied to the point source and the extended light source respectively.The results show that the illumination uniformity of the free-form surface lens based on the point light source is 54%,the illumination uniformity is 92% after optimization,and the illumination uniformity is 38% higher than the unoptimized illumination.The unoptimized illumination uniformity based on the extended light source free-form surface lens is 72%,the illumination uniformity after optimization is 89%,which is 17% higher thanthat before optimization.The unoptimized light intensity of the free-form surface-based lens with extended light source is 52%,the light intensity uniformity after optimization is 91%,which is 39% higher than that before optimization.