Author(s): Dong, HB (Dong, Haibo); Zhou, XY (Zhou, Xuyan); Hu, M (Hu, Man); Ma, Y (Ma, Yuan); Qi, AY (Qi, Aiyi); Zhang, WQ (Zhang, Weiqiao); Zheng, WH (Zheng, Wanhua)

Source: PHOTONICS Volume: 11  Issue: 6  Article Number: 513  DOI: 10.3390/photonics11060513  Published Date: 2024 JUN  

Abstract: Based on the demand for high-power output, a spatial beam combining 7-channel quantum cascade lasers (QCLs) is demonstrated in this paper. A "2 + 3 + 2" stepped structure is designed to convert the seven beam spots into a circular arrangement. An aspherical lens with a large numerical aperture (NA) of 0.85 and a focal length of 1.873 mm is used in each single QCL for collimation, and seven reflectors are utilized in the 7-channel QCLs combined in the spatial beam. After combining the spatial beam, the maximum continuous output power of the system is 3.6 W, and the beam quality M2 is 5.59 in the fast axis and 8.3 in the slow axis, respectively.