History of X-ray fluorescence analysis

Before the second world war, principles and excitation conditions of X-ray fluorescence analysis had been precised; however cathodic excitation was in greater favor, specially because of the lack of sensitivity of the photographic plate; in the meantime, fundamental spectroscopy was in progress and the benefits of it would furthermore facilitate the expansion of the X-ray fluorescence. After the war, the use of photon counters allowed design? building and trading of several types of spectrometer suitable far routine analysis (sequential or simultaneous, wavelength or energy- dispersive ...). The number of units in use rapidly increased, with progresses in sampling and quantization. Finally, since about twenty five years, with the advent of the microcomputing and the development of the semiconductor detectors, the analysis was made easier and the application field larger: the number of the units in use still. increases, but not so much as far as the wavelength-dispersive devices are concerned.