【摘要】 在通过隧道结形成的多有源区串联结构的半导体激光器中，由于发光区域之间通常缺乏有效的横向光学耦合，各有源区的激射光斑在远场呈现多个非相干的离散空间分布。经过快轴准直后，输出光束表现为一系列相对于光轴对称的离散角度分布，不仅导致远场发散角显著增大，还使远场强度分布维持多光斑结构。经光学系统聚焦或成像后，引发焦斑质量退化，限制光纤耦合效率及输出光束亮度的提升。针对该问题，本文提出基于临界角调控的全反射棱镜组和对称式高反射棱镜结构的光束整形方法，通过临界角下的选择性反射实现多发射区光束的角度重构，使角空间中原本离散的三峰分布经整形后合成为单峰集中分布，快轴发散角由0.52°压缩至0.11°，实现约79%的角度压缩率，提升了多有源区光束方向的一致性。结合快轴暗区压缩棱镜与伽利略缩束系统，进一步实现快慢轴光束参数积的匹配。整形后，快轴光束参数积由54.6 mm·mrad降低至22.8 mm·mrad，焦平面光强分布由“三光斑离散分布”转变为“单光斑集中分布”，并将聚焦光束耦合进NA0.22、芯径300μm的光纤中。系统峰值输出功率达630 W，光-光转换效率为78.8%。此外，通过装调与加工容差分析、热-结构耦合仿真及光谱色散与热致折射率效应分析评估了全反射角度整形镜的稳定性与可实现性，表明该光束整形与合束方案具有良好的光学稳定性和工程应用前景。更多还原

【Abstract】 In tunnel-junction-based semiconductor lasers with cascaded multi-active-region structures, the emission regions are typically optically isolated in the lateral direction, leading to multiple incoherent and spatially separated farfield patterns. After fast-axis collimation, the output beam exhibits a series of angularly symmetric but discrete patterns, which significantly increase the far-field divergence and maintain a multi-spot intensity profile. When the beam is focused or imaged, this angular separation degrades the focal quality, thereby limiting the fiber-coupling efficiency and output brightness. To address this issue, a beam-shaping method based on critical-angle-controlled total internal reflection(TIR) prisms is proposed. The design employs a TIR prism array in combination with a symmetric high-reflectivity prism to reconstruct the angular distribution of emissions from multiple active regions via selective reflection near the critical angle. As a result, the initially discrete triple-peak distribution in angular space is transformed into a single concentrated peak, reducing the fast-axis divergence from 0. 52° to 0. 11°, corresponding to an angular compression ratio of approximately 79%. This effectively enhances the directional uniformity of the multi-emitter output beam. By integrating a fast-axis dark-zone compression prism with a Galilean beam-compression system, the beam parameter products(BPPs) of both the fast and slow axes are further balanced. After beam shaping, the fast-axis BPP decreases from 54. 6 mm·mrad to 22. 8 mm·mrad, while the focal-plane intensity evolves from a discrete triple-spot pattern to a single compact spot. The focused beam is efficiently coupled into a 300 μm-core fiber with a numerical aperture of 0. 22, achieving a peak output power of 630 W and an optical-to-optical conversion efficiency of 78. 8%. Furthermore, analyses of assembly and fabrication tolerances, thermo-mechanical coupling, and spectral dispersion as well as thermo-optic effects confirm the stability and feasibility of the proposed TIR-based beam-shaping and combining scheme, demonstrating its strong potential for high-brightness multi-emitter semiconductor laser systems.更多还原