Fluorescence: When a specific wavelength of light is irradiated, it can absorb light energy and enter an excited state. Because the excited state is unstable, it will immediately release energy (light) and transition to a lower energy level. When the light is stopped, the luminescence phenomenon disappears immediately.
Phosphorescence: The luminescence process is very similar to that of fluorescence, but when entering an excited state, electrons have multiple spins, so they will slowly transition their energy to a lower energy level. When the incident light stops illuminating, the luminescence phenomenon continues (there are a considerable number of electrons staying in T1)
Equation:S0+hv0➡S2➡S1➡T2➡T1➡S0+hv1
S: Singlet state
h: Planck constant
T: Triplet state
Both are cold luminescence, which means that the object does not generate a lot of heat during the process of luminescence, and generally can be maintained at room temperature.
Resolution method: The duration of continuous light emission is shorter than 10^-8 seconds is called fluorescence, and longer than 10^-8 seconds is called phosphorescence.
#reference #yt#fluorescenceandphosphorescence #physics#fluorescence #phosphorescence
