Method and apparatus for the atom absorption spectral analysis

摘要

There is disclosed an atomic absorption analyzer which provides automatic background absorption compensation. Pulses of radiant energy from a continuous radiant energy source and a resonant frequency source are both directed alternately along sample and reference beam paths. The detector signal is sorted and handled to provide a signal which is (log PR - log PS) - (log AR - log AS) where PR is proportional to the resonant radiation passing the reference path, PS is proportional to the resonant radiation passing the sample path, AR is proportional to the auxiliary radiation passing the reference path, and AS is proportional to the auxiliary radiation passing the sample path. The function log PR - log PS is a function of the total absorbance in the sample path while log AR - log AS is a function of the background absorbance in the sample path. The resulting signal is therefore proportional only to the free atom absorbance of the element of interest.