Spectro-chemical analyser appts. - has laser beam source emitting coherent light focussed on target esp. for laser micro-spectral analysis

摘要

The laser beam is guided via a guide prism and focussed by a lens onto a target. Before the beam reaches the target, a V-shaped glass plate deflects part of the beam onto the surface of an auxiliary target. When the beam strikes the target, a small quantity of target material evaporates and a microplasm appears. The radiation from the auxiliary target passes through the marginal zone of the microplasm. With the optical system the ultra-violet component is guided into a gap of the spectrograph. The microplasm absorbs the radiation at certain wavelengths. A spectrum characterising the composition of the target is obtained and the radiation is imaged on the spectrograph gap.