LED lamp beads are light emitting diodes.
LED English for (lightemittingdiode), LED lamp bead is the English abbreviation of lightemittingdiode LED, which is a popular name.
The terminal voltage of the PN junction constitutes a certain barrier, and when the forward bias voltage is added, the barrier decreases, and most carriers in the P region and N region diffuse to each other.
Because the electron mobility is much larger than the hole mobility, a large number of electrons will diffuse to the P-region, constituting the injection of a few carriers in the P-region. These electrons combine with holes in the valence band, and the resulting energy is released in the form of light energy. This is the principle of PN junction luminescence.