一体化透镜阵列光束整形系统设计

Design of Integrated Lens Array Beam Shaping System

半导体激光器在激光扫描中得到了广泛应用,但由于其快慢轴发散角差异较大,需要进行光束整形。为提高线阵半导体激光器的光束均匀性,并满足小型扫描成像系统的微型化需求,提出一体化透镜阵列光束整形系统设计方案。系统采用一体化非球面透镜对高斯光束进行整形,快轴进行准直,慢轴进行扩束,能够获得高长宽比、光强均匀分布的线光束。理论分析一体化非球面透镜阵列进行准直扩束的原理,依据费马原理确定系统初始结构参数。利用光学设计软件对系统进行仿真优化,得到快轴发散角为2.8 mrad、慢轴发散角为48.93°(长宽比为325)、能量利用率为88.79%、能量均匀度为94.51%的线光束。结果表明,此方法整形效果理想、结构简单、体积小,符合未来光束整形系统微型化的发展趋势。

Semiconductor lasers are widely used for laser scanning;however,beam shaping is required because of the significant difference in their fast and slow axis divergence angles.In this study,a design scheme of the integrated lens array beam shaping system is proposed to improve the beam uniformity of the laser diode array and satisfy the miniaturization requirements of the small scanning imaging system.An integrated aspheric lens is used to shape the Gaussian beam.The fast axis is collimated,the slow axis is expanded,and a linear beam with a high aspect ratio and a uniform light intensity distribution can be obtained.Theoretically,the principle of collimation beam expansion of the integrated aspheric lens array is analyzed.The initial structural parameters of the system are determined according to Fermat principle.The system is simulated and optimized using optical design software,and a linear beam with a fast axis divergence angle of 2.8 mrad,slow axis divergence angle of 48.93°(aspect ratio of 325),energy utilization rate of 88.79%,and energy uniformity of 94.51%is obtained.The results show that the shaping effect of the proposed method is ideal.The proposed system has a simple structure and a small size,which is consistent with the development trend of miniaturization of beam shaping systems in the future.