衍射微透镜阵列用于半导体激光光束匀化

Homogenization of semiconductor laser using diffractive micro-lens array

摘要: 提出了一种用衍射微透镜阵列对半导体激光光束进行匀化的方法，解决了折射型微透镜阵列难于实现高填充因子、高精度面型的难题。基于标量衍射理论，设计了具有多阶相位结构的衍射微透镜阵列。采用菲涅耳衍射公式，推导了半导体激光从输入面到输出面的光场计算公式。数值模拟了成像型微透镜阵列匀化系统，并研究了微透镜口径及相位台阶数对焦斑均匀性的影响。结果表明：当衍射微透镜的口径D=0.27 mm、相位台阶数L=16 时，可获得不均匀性约为5%、系统能量可利用率达97%的均匀焦斑。

Abstract: In order to solve the problem that the high fill factor and accuracy of the refractive lens are difficult to realized, a new approach for homogenization of semiconductor laser by using diffractive micro-lens array was proposed. And diffractive micro-lens array with phase steps based on the theory of scalar diffraction was designed. The equation of intensity distribution in the focal plane was derived by the Fresnel diffraction equation. The imaging homogeneous system of diffractive micro lens array was simulated and the influences of diameter and phase steps of diffractive micro-lens on the intensity distribution were studied. The results show that the non-homogeneity about 5% and energy efficiency over 97% of the focal speck can be achieved with micro-lens diameter of 0.27 mm and phase steps of 16.