Efficient fiber coupling system for simultaneous beam shaping and wavelength combining based on misaligned stepped prism multiplexing

• Chang Liu, Lirui Xue, Ziyi Yan, Qian Qinyu, Haitao Chen, and Liwen Cheng
• received 03/21/2024; accepted 04/22/2024; posted 04/22/2024; Doc. ID 524357
• Abstract: Due to the substantial contrast in output beam quality between the two directions of the semiconductor laser,efficiently coupling the beam directly into the fiber is difficult. In this study, an efficient shaping method based on stepmultiplexing of misaligned step prisms is proposed and investigated systematically. Firstly, multiple laser stacks eliminate darkareas to improve beam quality through the full utilization of the transmission and reflection surfaces of the misaligned steppedprisms, which also improves the efficiency of the stepped prisms. Simultaneously realizes laser wavelength combining basedon reflective surface multiplexing, without affecting the quality of the beam on the premise of improving the output power.Finally, the whole beam shaping system is completed without using cut-transform-rearranging prisms. The method couplesfour groups of laser stacks into a single fiber with a fiber diameter of 400 µm and a numerical aperture of 0.22. It can be seenfrom the computer-simulated model outputs that the final fiber output power can reach 2255.4 W and that the system as a wholehas a light-to-light translation rate of 88.1%.