Glow Discharge Optical Emission Spectrometers 

L'introduction

The LECO GDS900 and GDS950 Glow Discharge Spectrometers deliver fast, accurate bulk and surface analysis for metals and coatings using advanced glow discharge technology and high-resolution CCD (charge-coupled device) detection. Both models provide reliable depth profiling and true bulk composition without the distortions of traditional spark Optical Emission Spectrometry (OES).  

The GDS950 stands out with its dual Direct Current / Radio Frequency (DC/RF) source, enabling analysis of non-conductive materials like coatings, ceramics, and glass, along with enhanced versatility for complex layered samples. The GDS900 is an excellent choice for routine metals analysis, while the GDS950 is ideal for labs requiring broader application coverage and integrated surface-to-substrate profiling. 

How Glow Discharge Spectrometers Work

Glow Discharge Spectrometry (GDS) is a high-performance form of Optical Emission Spectroscopy (OES) used for the rapid elemental analysis of solid samples. The process begins by mounting a flat sample onto a glow discharge source. Once the source is evacuated and backfilled with argon, an electric field is applied to create a stable, self-sustained plasma. 

Inside this plasma, argon ions are accelerated toward the sample surface. Through a process called cathodic sputtering, these ions eject surface atoms into the plasma, where they collide with energetic electrons and become electrically excited. As these atoms relax, they emit photons at unique wavelengths—the “spectrochemical signature” used in optical emission spectroscopy to identify specific elements. 

A high-resolution spectrometer uses CCD arrays to record these OES signals. Because the light intensity is proportional to the concentration of the atoms, the system can precisely quantify the sample chemistry by calibrating known standards. 

A primary advantage of GD-OES is its ability to generate a Compositional Depth Profile (CDP). By measuring the emission signals continuously as the plasma sputters deeper into the material, GDS uniquely validates the entire composition in a single run. This provides a detailed map of both external surface treatments (coatings) and the underlying internal “bulk” alloy, making it an essential tool for material validation. 

Instrument Support

Ensure reliable instrument performance with extensive support, training, and maintenance services. Need tailored support for your glow discharge spectrometers? Our experts are standing by.