Excellent LED electronic screen is suitable for all kinds of temperature, weather and various occasions, and the short-range and long-distance lighting must also have good effect. Especially for large concerts, the lighting with special effects must be excellent, but sometimes the brightness of LED is different. Why does the brightness of LED electronic screen not match? long-term experience summarizes the following three factors that may cause led brightness mismatch:
1. Luminescent element
In the production process, the brightness of LED light-emitting diodes remains unchanged. However, the countermeasures adopted by LED electronic display enterprises are eating separately after the completion of production, so the lower the brightness of two adjacent documents, the better the consistency, but the worse the appearance of low quality and high inventory. Therefore, each production enterprise adjusts the brightness difference between two adjacent files to 20%.
2. Driving element
Led full-color display driver components are usually constant current driver chips, such as mbl5026. These chips contain 16 constant current driver outputs, and the current output value can be set by resistance. The error of each output on the same chip is controlled within 3%, and that of other chips is controlled within 6%. It is normal for LED electronic screen to display 25% brightness error between pixels. If the LED is not a full-color LED display of the same level, the brightness error can be increased by 40% or more.
Outdoor LED advertising screen
In addition, it is worth noting that the LED electronic screen brightness mismatch is the root cause of the screen. In the future, it can not be calibrated with the calibration device, only through the manufacturing process of the LED display manufacturer. To purchase a screen with mismatched brightness, contact your service provider or manufacturer to resolve the problem.
3. The materials are mixed in the production process, and different batches of gratings are used.
If the color of LED electronic display is different, how to solve it?
Method 1: change the current flowing through the LED, the general LED tube allows continuous working current of about 20 mA. In addition to the saturation phenomenon of red LED, the brightness of other LEDs is basically proportional to the flow current.
The second method is to use the visual inertia of human eyes and pulse width modulation to achieve gray control. That is, the pulse width (i.e. duty cycle) of the light is changed periodically. As long as the repeated illumination period is short enough (that is, the refresh rate is high enough), the human eye will not feel the jitter of luminous pixels. Pulse width modulation (PWM) is more suitable for digital control. Therefore, almost all LED electronic displays are widely used in computers to provide display content and display LEDs, and the gray level is controlled by PWM.
How to ensure uniform brightness of LED electronic display screen
