Physical Principle of Spectral Analyser

    Atoms of any element are composed of nuclei and electrons moving around them. Electrons outside the nucleus are distributed in different levels according to their energy levels. Therefore, a nucleus can have many levels.
The lowest energy level state is called ground state level (E0 = 0), the rest is called excited state level, and the lowest energy level is called the first excited state. Normally, the atom is in the ground state, and the electron outside the nucleus moves in the orbit with the lowest energy.
If a certain external energy, such as light, can be supplied to the ground state atom, when the external light energy E is exactly equal to the energy level difference E between the ground state and a higher energy level in the ground state atom, the atom will absorb the light of this characteristic wavelength, and the outer electrons will transit from the ground state to the corresponding excited state, resulting in the atomic absorption spectrum.
After the transition to a higher energy level, the electrons in the excited state are in the excited state, but the electrons in the excited state are unstable. After about 10-8 seconds, the excited state electrons will return to the ground state or other lower energy levels, and the energy absorbed during the transition will be released in the form of light. This process is called atomic emission spectroscopy. It can be seen that the process of atomic absorption spectrometry absorbs radiation energy, while the process of atomic emission spectrometry releases radiation energy.