一、绪言原子吸收、等离子体发射光谱等所谓原子光谱分析法是目前进行微量金属元素日常分析的主要方法。以这些方法分析含量在检出限附近的试样时,一定要增加放大器的增益,其必然结果是随之而来的噪音的增加和分析方法精密度的下降。这些噪音是从哪里来的呢?或者说决定原子吸收分析等方法精密度(信噪比)的主要因素在哪里?弄清这类问题是十分有意义的。最近,由于数字技术的发展和电子计算机的普及, First, the introduction Atomic absorption, plasma emission spectroscopy and other so-called atomic spectrometry is the main method of routine analysis of trace metals. When analyzing samples with a content near the detection limit by these methods, be sure to increase the gain of the amplifier, with the consequential result of increased noise and reduced precision of analytical methods. Where do these noises come from? Or where are the main factors that determine the precision (signal-noise ratio) of methods such as atomic absorption spectrometry? It makes sense to understand such issues. Recently, due to the development of digital technology and the popularization of electronic computers,