The Lyman series describes the emission of ultraviolet light with a wavelength of about 121.6 nm due to an electron transition in hydrogen from n=2 to n=1.
An electron goes from a higher energy level to a lower energy level during the hydrogen electron transition.
We can take into consideration the transition from the second energy level (n=2) to the first energy level (n=1) in order to suggest a transition using light with a wavelength in the ultraviolet (UV) range (10-400 nm) and n=1.
An electron releases energy in the form of light when it changes from having n=2 to n=1.
The energy differential between the two levels determines the light's energy.
The high energy of the light released in the UV region indicates a significant energy differential between the two levels.
In hydrogen, for instance, the shift from the n=2 to n=1 level is accompanied by the emission of ultraviolet light with a wavelength of about 121.6 nm.
The Lyman series, so named for its discoverer, Theodore Lyman, refers to this transition.
It is the hydrogen spectrum's shortest wavelength transition that is visible in the ultraviolet.