LED display is popular in many fields because of its advantages of energy saving, environmental protection, long life and so on. But the temperature is very important to the LED display. The influence of temperature on the LED display is related to the lifetime, light efficiency and color of the LED display. So the right temperature is very important to the LED display screen.
Excessive temperature can lead to the complete destruction of the LED display screen, as shown in the following two points
When the working temperature of the LED display exceeds the load-bearing temperature of the chip, the luminous efficiency of the LED display will be reduced rapidly, resulting in obvious light decay and damage.
LED display is mostly encapsulated with transparent epoxy resin. If the junction temperature exceeds the solid phase transition temperature (usually 125 C), the encapsulation material will change to rubber shape and the thermal expansion coefficient will rise sharply, which will lead to the open circuit and failure of the LED display.
Temperature rise will shorten the life of the LED display. The life of the LED display is reflected in its light decay, that is, the brightness will become lower and lower until it is extinguished. Usually, the lifetime of LED display is defined as the time when the luminous flux decreases by 30.
There are several reasons for the light fading of the LED display screen.
The defects in LED display chip materials will multiply and multiply rapidly at high temperatures until they invade the luminous region and form a large number of non-radiative composite centers, which seriously reduces the luminous efficiency of LED display. In addition, at high temperatures, micro-defects and fast-spreading impurities from the interface and the panel will also introduce into the luminous region, forming a large number of deep levels, which will also accelerate the optical decay of LED display devices.
Transparent epoxy resin will denaturate and yellowing at high temperature, which will affect its light transmission performance. The higher the working temperature, the faster the process will go. This is another main reason for the light decay of LED display screen.
The light decay of phosphor is also a main reason that affects the light decay of LED display screen. Because the phosphor decays seriously at high temperature, high temperature is the main cause of the light decay of LED display screen and shorten the life of LED display screen.