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Research on multi-focus laser based on refractive Fresnel lens

Laser multi-focus separation technology is used as an efficient way to cut thick transparent materials and composites. In this paper, we propose a multi-focal design and experimental scheme based on refractive Fresnel lenses. Various refractive type multi-focal Fresnel lens designs were completed by combining theoretical calculations and Trace Pro software simulations, and the designed tri-focal optical system was experimentally verified by using N-BK7 glass, and the experimental errors were analyzed. The results show that the organic plastic (PMMA) processed multi-focal Fresnel lens can be applied to the high-power laser multi-focal optical system. The multi-focal optical system is highly stable and low cost, and has great application prospects.