When a component is subjected to Direct Current; When the forward bias voltage derived from DC) is applied, the Electron driving (Electron) and Hole are injected by the cathode and anode respectively. When the two meet and combine in the conduction, the so-called electron-hole Capture is formed. When a chemical molecule is excited by foreign energy, if the Electron Spin and the ground state Electron pair up, it is a Singlet, and the light it emits is so-called Fluorescence. Conversely, if the excited and ground state electrons spin unpaired and parallel, they are called Triplet states, and the light they release is called Phosphorescence.

When the state position of electrons is returned to steady-state low energy levels by excited high energy levels, their energy is released separately on a Light Emission or Heat Dissipation method, with portions of the photons being consumed as a display function; However, the triplet phosphorescence cannot be observed in organic fluorescent materials at room temperature, so the theoretical limit of the luminous efficiency of PM-OLED elements is only 25%.
The principle of PM-OLED luminescence is to convert the released energy into photons by using the material energy order difference, so we can choose the appropriate material as the luminescence layer or mix dyes in the luminescence layer to get the luminescence color we need. In addition, the general combination reaction of electrons and holes is within tens of nanoseconds (NS), so the PM-OLED response speed is very fast.