Tag: LED display light attenuation, LED technology, LED display manufacturers 
LED display light attenuation is the light weakens during transmission, the light fades of LED display made by each companies are different, there are light decay also for high-power LED display, and it's have direct relationship with temperature, mainly depend on the chip, phosphor and packaging technology. The LED display luminosity attenuation (including luminous flux attenuation, color change, etc.), is a measure standard of the LED display quality, also it is great concern to many LED display manufacturers and LED display user.
According to the lifespan definition for the LED display product of the LED display industry, the lifetime of LED display is the cumulative work time from initial value till light fades to 50% of the original value. This means that the LED display still bright when LED display achieves its end life time. However, in illumination the light is not allowed if the light output attenuation on its 50%. Typically, indoor lighting the light decay can not greater than 20%, outdoor lighting fades is not allowed greater than 30%.
At present, the white LED display light attenuation is one of the most important issues for it’s enter the civilian lighting market. And manufacturers generally tested attenuation in three ways:
1. Visual method: continuously lit LED display, observe the brightness and color changes by human eyes.
2. Use light color testing instrument: that during continuously lit LED display process, take the LED display into the light color test instrument frequently, and record test results, and report test results by EXCEL or other tools.
3. Use professional testing instruments to measure the light fades, that is put the LED display in the test equipment, during the continuously lit, the system will have real-time tracking for the LED display brightness and color change, automatically generate information sheet.
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