Opt Lett. 2018 Aug 1;43(15):3465-3468. doi: 10.1364/OL.43.003465.
The femtosecond filament-induced breakdown spectroscopy (FIBS) technique coupled with principal component analysis (PCA) is demonstrated for standoff (ST) analysis of metals, alloys (Al, Cu, brass, stainless steel), and bimetallic strips (Ag@Cu, Ag@Au with varying weight percentages). The experiments were performed by analyzing the filament-produced plasma at ∼6.5 m from the laser. The plasma emissions were collected using a Schmidt-Cassegrain telescope (6″ f/10) at ∼8 m away. The variations in intensities of persistent atomic transitions in the FIBS spectra clearly reflected the varying weight percentage in bimetallic strips. Furthermore, PCA was successfully utilized to discriminate the metals, alloys, and bimetallic strips batch wise and altogether. Our results demonstrate the capability of femtosecond ST-FIBS for ST analytical applications.
飞秒丝状诱导击穿光谱（FIBS）技术与主成分分析（PCA）相结合，用于离轴（ST）分析金属、合金（Al、Cu、黄铜、不锈钢）和双金属带（Ag@Cu、Ag@Au 重量百分比不同）。实验通过分析在距离激光约 6.5 m 处产生的丝状等离子体进行。等离子体发射使用 Schmidt-Cassegrain 望远镜（6″ f/10）在距离约 8 m 处收集。FIBS 光谱中持久原子跃迁强度的变化清楚地反映了双金属带中重量百分比的变化。此外，PCA 成功地用于分批和整体区分金属、合金和双金属带。我们的结果证明了飞秒 ST-FIBS 用于 ST 分析应用的能力。
