Becker-Ross H, Florek S, Heitmann U, Weisse R
Institut für Spektrochemie und angewandte Spektroskopie (ISAS), Laboratorium für spektroskopische Methoden der Umweltanalytik (LSMU), Rudower Chaussee 5, D-12489, Berlin, Germany.
Anal Bioanal Chem. 1996 Jun;355(3-4):300-3. doi: 10.1007/s0021663550300.
The influence of the spectral bandwidth of the spectrometer on the performance of the spectrometer is of great importance in atomic absorption spectrometry using continuum source (CS-AAS). For a theoretical analysis of the detection of small absorbances two cases have to be taken into account: as long as the limiting noise of the signal is given by the detector noise an increase in spectral bandwidth of the spectrometer implies an improvement in the limit of detection. In contrast, if the noise of the signal is dominated by the photon shot noise the detection limit should become independent of the spectral bandwidth. In this case the spectral bandwidth of the spectrometer should be chosen equal to the bandwidth of the absorption line to avoid spectral interferences. Theoretical calculations are presented for the dependence of the characteristic mass on the spectral bandwidth in case of CS-AAS measurements. The results are compared with experimental measurements for six different elements using continuum source as well as line sources. The investigations were done using a double echelle monochromator (DEMON) which offers a high spectral resolution lambda/Deltalambda of about 140,000.
在使用连续光源的原子吸收光谱法（CS - AAS）中，光谱仪的光谱带宽对其性能的影响至关重要。对于小吸光度检测的理论分析，必须考虑两种情况：只要信号的极限噪声由探测器噪声给出，光谱仪光谱带宽的增加就意味着检测限的改善。相反，如果信号噪声由光子散粒噪声主导，检测限应与光谱带宽无关。在这种情况下，应选择光谱仪的光谱带宽等于吸收线的带宽，以避免光谱干扰。本文给出了CS - AAS测量中特征质量对光谱带宽依赖性的理论计算。将结果与使用连续光源以及线光源对六种不同元素进行的实验测量结果进行了比较。研究使用了一台双阶梯光栅单色仪（DEMON），其提供约140,000的高光谱分辨率λ/Δλ。
