The Optical Cell and Flame
The optical cell is fused silica glass tube (transparent in the visible and UV wavelengths and thermally stable at high temperatures) through which the HCL's beam passes on the way to the monochromator and PMT. In some instruments it sits on top of the normal AAS air/acetylene flame. The
gaseous, metalloidal hydride flows into the optical cell from the hydride generation module pushes
by an inert purge gas. In the optical cell it decomposes into the elemental form which can absorb the
HCL's beam.