The 1.5th-generation “three-high/one-excellent” YDF specialty laser fiber
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摘要:
面向高端特种光纤激光器研制需求,突破限制光纤激光器系统功率输出和性能提升的技术瓶颈,中国工程物理研究院化工材料研究所高功率光纤激光技术所地联合创新中心团队采用模式裁剪制备工艺技术,率先推出了国内首创、特别适合976 nm-LD端面泵浦方式(976技术路线)的第1.5代YDF特种激光光纤,有效提升了光纤激光系统的模式不稳定阈值(TMI),显著优化了激光输出的光束质量。相对于目前普遍使用的第1.0代铝磷硅三元体系光纤(Yb-APS),第1.5代YDF特种激光光纤的激光功率提升约20%,光束质量M2优化约20%,集中展现了高功率、高效率、高TMI阈值、M2优化的“三高一优”的技术特点,可供工业市场高端客户选择和强激光技术领域应用。
Abstract:For the development of high-end fiber lasers and breaking through the technical bottlenecks limiting the output power and performance improvement of fiber laser systems, the Joint-Innovation Center of High Power Fiber Laser Technology, Institute of Chemical Materials (ICM) of China Academy of Engineering Physics (CAEP) , adopted the mode-tailoring fabrication process technology, theoretically designed and firstly fabricated the 1.5th-generation (1.5G) YDF specialty laser fibers, which are particularly suitable for 976 nm-LD end-pumping method (976-technology route) to effectively improve the threshold of mode instability (TMI) and significantly optimize the beam quality of laser output. Compared with currently widely-used 1.0G Yb-APS fiber, 1.5G YDF specialty laser fiber shows about 20% improvement both in laser output power and beam quality. The 1.5G YDF specialty laser fibers fully demonstrate technical characteristics of “three-high/one-excellent”—high power, high efficiency, high TMI threshold, and M2 optimization—which can be selected by high-end customers in the industrial market and/or applied in high power laser fields.
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Key words:
- fiber laser /
- threshold of mode instability /
- beam quality /
- single mode /
- fiber design and fabrication /
- laser fiber
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表 1 第1.5代YDF特种激光光纤参数
Table 1. 1.5G-YDF specialty laser fiber parameters
1.5G-YDF laser fiber laser power/kW beam quality M2 LMA-14/250-YDF 2~3 ~1.05 LMA-20/400-YDF 3~4 ~1.10 LMA-25/400-YDF 4~6 ~1.20 PLMA-20/400-YDF 2~3 ~1.20 PLMA-25/400-YDF 3~5 ~1.30 表 2 第1.5代LMA-14/250-YDF特种激光光纤参数
Table 2. 1.5G LMA-14/250-YDF specialty laser fiber parameters
parameter unit specification peak cladding absorption @915 nm dB/m 0.50±0.15 peak cladding absorption @976 nm dB/m 1.50±0.25 cladding attenuation@1 095 nm dB/km ≤10 core attenuation@1 200 nm dB/km ≤10 core attenuation@1 300 nm dB/km ≤15 core NA — 0.070±0.005 cladding NA(5%) — ≥0.46 core/clad offset μm ≤1.0 core diameter μm 14.3±0.5 clad diameter (flat-to-flat) μm 250±5.0 max. output power kW ≥2.0 slope efficiency@976 nm % ≥78 beam quality M2 — ~1.05 -
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