: An Optical Transfer Interface System for An Axially Viewed Plasma That Improves Recoveries of Analyte Signals in a Variety of Matrices When Compared to Commercial Instruments.

The presentation will describe a short depth of field transfer optics ( US Patent # 6,1220,050) that helps in the recovery of analyte signals in an ICP-AES. With slight modifications using a photon stop it was possible to optically section the plasma and map the ICP-AES discharge in a matrix of 1000 ppm Ca and other elements. The data will show that most of the matrix effects occurs at the base of the plasma, and analyte recoveries improve when the plasma is viewed down stream of the load coil. Measurements of hydrogen emission show no change in the electron number density throughout the axis of the plasma. This suggests that the observed signal reduction is due to the matrix redistributing the excitation energy in the plasma.