光谱仪器信噪比与建模波长数对光谱分析精度的影响  

The Effects of Signal to Noise Ratio of Instrument and Number of Wavelengths on the Accuracy of Spectral Analysis

作　　者：李刚[1] 赵喆[1] 王慧泉[1] 林凌[1] 吴晓荣 张宝菊[2] 

机构地区：[1]天津大学精密测试技术及仪器国家重点实验室,天津300072 [2]天津师范大学物理与电子信息学院,天津300387

出　　处：《光谱学与光谱分析》2012年第8期2286-2289,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(30973964);天津市应用基础及前沿技术研究计划项目(11JCZDJC17100);天津市科技计划项目和科技型中小企业创新基金项目(10ZXCXSY10400)资助

摘　　要：为了研究光谱建模分析中光谱仪器噪声和参与建模的波长数两个因素与定量分析精度之间的关系,针对不同信噪比对模型精度的影响、参与建模的波长数与分析精度的关系、不同信噪比波段中多波长参与建模对分析精度的影响三个方面进行了理想样本建模分析。实验结果表明:光谱测量仪器的噪声水平直接影响建模分析误差,而使用多波长尤其是信噪比较好的波段的光谱参与线性建模,近似满足波长数每增加4倍,分析精度提高2倍的关系,能够在一定程度上弥补信噪比的不足。研究为在光谱分析中充分利用和提高光谱仪器信噪比、合理选择参与建模波长数及波段,从而提高光谱定量分析精度提供了实验基础和理论指导。In order to study the influence of the two factors, the signal to noise ratio （SNR） of instrument and number of wave-lengths, on the accuracy of quantitative analysis in spectral modeling analysis, the influences of different SNRs, the number of wavelengths participating in partial least square regression, and multi-wavelength modeling in different SNR bands were taken into account. The relationships between these factors and quantitative analysis accuracy were explored by modeling analysis ex- periments. The results show that the analysis accuracy is directly related to the SNR of instrument. And increasing wave- lengths, especial the ones with high SNR, reflects a phenomenon that four times of wavelength number will bring 2 times accuracy increasing, which can compensate for the lack of SNR. The research provides the experimental basis and theoretical guidance to improve the model＇s quality and reduce the prediction error by the utilization and improvement of the instrument＇s SNR and the reasonable choice of wavelengths and bands of modeling.

关 键 词：信噪比 波长数 光谱分析精度 纯吸收 偏最小二乘 

分 类 号：O657.3[理学—分析化学]