High-efficiency multi-spot beam generation with an all-fiber SMF-SCF structure

We propose an efficient, fully fiber-based method for generating multi-spot beam patterns using single-mode fiber (SMF) and square-core fiber (SCF) structures. This technique leverages multimode interference in the SCF to produce configurable square lattice beam patterns, such as 2 × 2, 3 × 3, and 4 × 4 arrays, by simply adjusting the SCF length. Both simulations and experiments at a wavelength of 1060 nm validate the approach, demonstrating high power uniformity, minimal loss, and excellent stability across beam configurations. Initial testing of multi-spot laser drilling on metal surfaces shows that increased beam spot counts can significantly enhance processing efficiency. This SMF-SCF structure offers substantial potential for scalable, compact, and high-precision applications in photonics, laser manufacturing, and biomedical imaging, where rapid processing and parallel operation are critical.