What effect does high temperature operation have on the led display? With the increasing use of LED display screens today, in order to maximize the advantages of the display screen, users should have a certain understanding of the maintenance of the LED display screen. Whether it is an indoor LED display or an outdoor LED display, heat will be generated during operation, and the generated heat will cause the temperature of the LED display to rise. But, do you know what effect does high temperature operation have on the led display? Let’s talk about Shenzhen LED display manufacturer Tuosheng Optoelectronics.
Under normal circumstances, indoor LED displays generate less heat due to low brightness and can dissipate naturally. However, the outdoor LED display screen generates a lot of heat due to its high brightness, and it needs to be dissipated by an air conditioner or an axial fan. Since the LED display is an electronic product, an increase in temperature will affect the light attenuation of the LED display lamp beads, thereby reducing the working efficiency of the driver IC and shortening the service life of the LED display.
1. LED display open circuit failure: the working temperature of the LED display exceeds the load temperature of the chip, which will quickly reduce the luminous efficiency of the LED electronic screen, cause obvious light attenuation and cause damage; the LED display is mainly made of transparent epoxy resin . For packaging, if the junction temperature exceeds the solid phase transition temperature (usually 125°C), the packaging material will turn into rubber and the coefficient of thermal expansion will rise sharply, resulting in open circuit failure of the LED display. Excessive temperature will affect the light decay of the LED display. The life of the LED display is reflected by its light attenuation, that is, the brightness will become lower and lower with the passage of time until it goes out. High temperature is the main cause of the light attenuation of the LED display, and it will shorten the life of the LED display. The light attenuation of different brands of LED displays is different, usually Shenzhen LED display manufacturers will give a set of standard light attenuation curves. The attenuation of the luminous flux of the LED electronic screen caused by high temperature is irreversible.
The luminous flux before the irreversible light attenuation of the LED display is called the “initial luminous flux” of the LED electronic screen.
2. Increasing temperature will reduce the luminous efficiency of the LED display: the temperature increases, the concentration of electrons and holes increases, the band gap decreases, and the electron mobility decreases; the temperature increases, the electrons in the potential well will reduce the holes The possibility of radiation recombination leads to non-radiative recombination (heating), thereby reducing the internal quantum efficiency of the LED display; increased temperature causes the blue peak of the chip to move to the long wave direction, causing the emission wavelength of the chip to mix with the phosphor. The mismatch of the excitation wavelength will also cause the external light extraction efficiency of the white LED display to decrease. Screen: As the temperature rises, the quantum efficiency of the phosphor decreases, the amount of light emitted decreases, and the external light extraction efficiency of the LED display decreases. The performance of silica gel is more affected by ambient temperature. As the temperature increases, the thermal stress inside the silica gel increases, causing the refractive index of the silica gel to decrease, thereby affecting the light efficiency of the LED display.