OES Principle

Material’s property is solely depended on it chemistry/composition. Composition of the material decides all basic design, parameters and processes which are to be used in fabrication industry. Now-a-days for analysis of chemistry we do not require waiting hours and days for result, rather chemistry of material is obtained within seconds. OES (Optical emission spectrometry) analyses and provides accurate result within seconds.


Optical emission spectrometry involves applying electrical energy in the form of spark generated between an electrode and a metal sample, whereby the vaporized atoms are brought to a high energy state within a so called “discharge plasma”. These excited atoms and ions in the discharge plasma create a unique emission spectrum specific to each element. Thus, a single element generates numerous characteristic emission spectral lines.


Therefore, the light generated by the discharge can be said to be a collection of the spectral lines generated by the elements in the sample. This light is split by a diffraction grating to extract the emission spectrum for the target elements. The intensity of each emission spectrum depends on the concentration of the element in the sample. Detectors (photomultiplier tubes) measure the presence or absence of the spectrum extracted for each element and the intensity of the spectrum to perform qualitative and quantitative analysis of the elements.


In the broader sense, optical emission spectrometry includes ICP optical emission spectrometry, which uses inductively coupled plasma (ICP) as the excitation source. The terms “optical emission spectrometry” and “photoelectric optical emission spectrometry,” however, generally refer to optical emission spectrometry using spark discharge, direct current arc discharge, or glow discharge for generating the excitation discharge.

Reference: Shimadzu literature

Keep reading, happy welding

Thank you,

KP Bhatt


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