What effect does high temperature status have on full-color LED display in summer

Time:2018-10-31 Views:242

After years of development, China‘s LED display market is now mature.It is reported that China accounts for about 80 percent of the global market share of LED displays, and the market is very large. Major LED display manufacturers in the world are also concentrated in China, especially in the eastern coastal areas.

In the past, China‘s LED display market has followed the foreign market. Due to immature technology, backward production capacity and insufficient innovation capacity, many products are imitated, resulting in products with little competitiveness.Over the years, the state has vigorously supported the development of high-tech industries, especially the strategic emerging industries, with greater support. The LED industry is one of the beneficiaries.Under the strong support of the national and local governments, China‘s LED display industry is booming, and a number of internationally known LED display companies have emerged, among which shenzhen derunser technology co., ltd. is one of them.

In today‘s increasingly widespread LED display applications, in order to maximize the use efficiency of the display, application enterprises should have the basic knowledge of LED display maintenance.Both indoor and outdoor LED displays will generate heat during operation, and the heat generated will increase the temperature of LED displays.But do you know what happens when the screen is working at high temperatures?Let‘s analyze it together.

Under normal circumstances, indoor LED display can generate less heat due to low brightness, which can radiate naturally.However, the outdoor LED display is high in brightness and generates large amount of heat, which needs to be cooled by air conditioning or axial fan.As the LED display is an electronic product, the rising temperature will affect the light decay of LED display beads, the working efficiency of driving IC and the service life of LED display.

The working temperature of led display panel exceeds the bearing temperature of the chip, which will rapidly reduce the luminous efficiency of led display panel, resulting in obvious light loss and damage.Led display in a transparent epoxy resin encapsulation, more if the junction temperature more than solid phase transition temperature is 125 ℃ (usually), the packaging materials will surge to rubber shape and thermal expansion coefficient, resulting in led display open and failure.

2. Too high temperature will affect the light attenuation of LED display.The life of the led display is reflected by its light decay, which means that as time goes on, the brightness decreases until it finally goes out.It is generally defined that the time of light flux attenuation of led display panel is 30.High temperature is the main cause of led display dimming and shortening led display life.Led display screens of different brands have different light attenuation, usually led display manufacturers will give a set of standard light attenuation curve.The light flux attenuation of led display caused by high temperature is irreversible. There is no unrecoverable light flux before the light attenuation of led display, which is called the "initial light flux" of led display.

The rising temperature will reduce the luminous efficiency of led display.As the temperature increases, the concentration of electrons and holes will increase, the gap width will decrease, and the electron mobility will decrease.As the temperature increases, the probability of radiation recombination between electron and hole in potential well decreases, resulting in non-radiative recombination (generating heat), thereby reducing the internal quantum efficiency of led display.The rise of temperature causes the blue-ray wave peak of the chip to shift towards the direction of long wave, which makes the emission wavelength of the chip and the excitation wavelength of phosphor not match, and also causes the reduction of external light extraction efficiency of white led display screen.As the temperature rises, the quantum efficiency of phosphor powder decreases, the output light decreases, and the external light extraction efficiency of led display decreases.The properties of silica gel are greatly affected by ambient temperature.As the temperature increases, the thermal stress inside the silica gel increases, leading to a decrease in the refractive index of the silica gel, which affects the luminous effect of the led display.

The effect of temperature on the luminous wavelength (light color) of led display.Led display can be divided into peak wavelength and main wavelength.The peak wavelength is the wavelength with the maximum light intensity, while the main wavelength can be determined by X and Y chroma coordinates, reflecting the color perceived by human eyes.Obviously, the variation of luminous wavelength of led display caused by junction temperature will directly cause human eyes to have different feelings of luminous color of led display.For an led display device, the bandgap width of the material in the luminous region directly determines the wavelength or color of the device.As the temperature increases, the forbidden band width of the material will decrease, leading to longer wavelength and redshift of color.

5. Too high temperature will limit the maximum injection current of led display.LED display when the choose and buy, should pay attention to choose LED display chip brands, packaging manufacturers, drive IC, switching power supply brand, brand is good or bad will affect the LED display itself product quality, and high degree of brand products, its itself produces less heat, also can better control the temperature of the LED display, so as to prolong the service life of the LED display.

LED display has great development prospect due to its advantages of energy saving, environmental protection and long life.LED display is sensitive to temperature: it can affect LED display life, light effect, color, etc.So the right temperature is crucial to the LED display.