Optical Emission Spectrometer (OES) operates based on two fundamental principles of physics:

Excitation and Emission of Electrons: When energy is applied to electrons in atoms, they absorb the energy and move to higher energy states or orbits. As the energy source is removed, the electrons return to their ground state, releasing the absorbed energy in the form of photons (light).

Unique Emission Wavelengths: Each element’s atoms emit photons at specific wavelengths. No two elements have the same emission wavelength, making each wavelength unique to a particular element.

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