基于激光诱导击穿光谱的波长校准法研究

Wavelength calibration method based on the laser induced breakdown spectroscopy

基于线列光探测器件的光谱仪具有多光谱通道探测的优点,以及其在物质光谱分析中担当的重要角色。分析了基于线列光探测器件光谱仪的波长准确度问题,提出利用激光诱导击穿原子光谱丰富波长校准特征波长谱线的思想。实验选用光谱波长范围为200 nm^600 nm的凹面光栅光谱仪、2048元焦平面的CCD器件和低压汞灯,分别对铜、铝、镁、钙、硅等5种样品进行了激光诱导击穿光谱试验;利用选取的10条激光诱导原子光谱波长数据并结合低压汞灯的10条特征谱线对光栅光谱仪重新进行波长校准,获取的试验数据有力地证明了这种思想的可行性。

The spectrometer based on linear optical detector has the advantage of multi-spectrum channel detection and it plays an important role in mass-spectrometry. The wavelength calibration for the spectrometer is discussed. A concept of using laser induced breakthrough atomic spectrum to enrich characteristic wavelength spectrum for wavelength calibration is put forward. A concave grating spectrometer, a 2048 elements CCD and a low voltage mercury lamp were used to carry out laser induced breakthrough spectrum test with 5 samples, such as Cu, A1, Mg, Ca and Si. The selected 10 laser induced atomic spectrum wavelength data and the 10 characteristic spectrum lines achieved with mercury lamp were used to recalibrate the wavelengths of the grating spectrometer. The feasibility of the concept is effectively validated.