ABSTRACT
The three analytical techniques of atomic absorption, emission, and fluorescence are very closely interrelated, but the greater versatility of the absorption method has resulted in its acceptance and development to a far greater extent than either flame emission or atomic fluorescence. Energy can also be transferred to the ground-state atom population in the form of electromagnetic radiation. Atomic absorption spectrometry is thus an analytical method for the measurement of amounts of elements based on the absorption of resonance radiation by their free atoms. Atomic absorption is essentially a quantitative technique. Instrumentation for making atomic absorption measurements on suitably prepared "real" samples consists of three main parts. These are the sample input or atomization system, the optical system, and the detector or data output electronic system. Only photomultipliers at the present time provide the high optical sensitivity required of detectors in modern atomic absorption instruments.
