The display shows that some parts of the image are not bright, or the areas that should be bright are not bright, and the areas that should not be bright are still on. Yes, yes, these can be caused by the pixels of the full color LED control card display being out of control, then the reason What is it, and how can we solve it? Full color LED display pixels runaway is a relatively common problem. What is the cause of this phenomenon, and how to solve it?
In general, the common display pixel composition is 2R1G1B (2 red lights, 1 green light and 1 blue light, the same applies below) and 1R1G1B, and the out of control is generally not the red, green, and blue in the same pixel. The lights are all out of control at the same time, but as long as one of the lights is out of control, we consider that the pixel is out of control.
Therefore, it can be concluded that the main cause of the out-of-control pixels of full-color LED display screens is the out-of-control LED lights. The main causes of LED lamp failure can be divided into two aspects: one is the poor quality of the LED itself; the other is the improper use of the LED.
LED failure cannot be found in the regular inspection test of LED. Under severe conditions such as high temperature, low temperature, and rapid temperature changes, it is caused by the difference in thermal expansion coefficients of LED chips, epoxy resin, brackets, inner leads, die-bonding adhesives, PPA cups and other materials, resulting in different internal stresses. The mechanism of LED failure caused by electrostatic discharge is very complicated. Equipment, tools, utensils, and human bodies may carry static electricity and discharge it. This static electricity ranges from several hundred volts to tens of thousands of volts. The discharge time is in the nanosecond range Level.
If the blue-green tube fails, the LED-PN junction is often caused by electrostatic discharge. Due to the complicated production process of LED display screens, electrostatic discharge cannot be prevented. Therefore, electrostatic protection must run through the entire production process.
In addition, under different occasions, the actual requirements of the pixel out-of-control rate are different. Full-color LED display indicators are required to be controlled within one percent; monochrome LED display indicators are required to be controlled within one-tenth. There is currently no good solution for full color LED display pixels.