The price may be an important factor affecting the purchase of LED display screen, but in addition to the price, the following points are also the top priorities.
1. Inefficiency
Since the full-color display screen is composed of tens of thousands or even hundreds of thousands of red, green and blue LED pixels, the failure of any color LED will affect the overall visual effect of the display screen. Generally speaking, according to industry experience, the failure rate of LED display screen from the start of assembly to the 72 hour aging before shipment should not be higher than 3/10000 (referring to the failure caused by the LED device itself).
2. Antistatic ability
LED is a semiconductor device, which is sensitive to static electricity and can easily lead to static electricity failure. Therefore, the anti-static ability is crucial to the life of the display screen. In general, the failure voltage of LED in human electrostatic mode test shall not be lower than 2000V.
3. Attenuation characteristic
Red, green and blue LEDs have the characteristics of brightness attenuation with the increase of working time. The attenuation speed of LED is determined by the quality of LED chips, auxiliary materials and packaging technology. Generally speaking, after 1000 hours and 20 mA normal temperature lighting test, the attenuation of red LED shall be less than 10%, and that of blue and green LED shall be less than 15%. The consistency of red, green and blue attenuation has a great impact on the future white balance of full-color LED display, and thus affects the display fidelity of the display.
4. Brightness
LED brightness is an important determinant of display brightness. The higher the LED brightness, the greater the margin of current usage, which is beneficial to saving power consumption and maintaining LED stability. LEDs have different angle values. When the chip brightness is set, the smaller the angle, the brighter the LED will be, but the smaller the viewing angle of the display screen will be. Generally, 100 degree LED shall be selected to ensure adequate viewing angle of the display screen. For displays with different point spacing and viewing distance, a balance point should be found in brightness, angle and price.
