Elemental Analysis with a Plasma Emission Echelle Spectrometer Employing a Charge Injection Device (CID) Detector

Abstract

An atomic emission spectrometer which allows simultaneous high-precision digital recording of the ultraviolet spectrum has been developed. The instrument employs both a custom-built echelle spectrometer and a custom-built slow-scan charge injection device (CID) based detector system. The system is capable of measuring the wide dynamic range of signal intensities associated with plasma emission sources, and sensitivity is comparable to that of photomultiplier-tube-equipped instruments. Unprecedented speed and flexibility for elemental analysis are provided by the ability to display background-subtracted emission spectra and to have the computer assist in spectral line identification. The design and performance of the optical system, methodologies for CID detector utilization in analytical spectroscopy, and techniques for wavelength calibration are presented. Examples for qualitative analysis and for the qualitative comparison of similar samples demonstrate the sensitivity, flexibility, and speed of the system.