A method for improving the uniformity of LED display screens based on CCD images

As a widely used display terminal, the uniformity of Light-emitting Diode(LED) display screen brightness has a significant impact on its display effect. To improve the brightness uniformity of LED display screens, the Charge-coupled Device(CCD) image method is often used. This method uses a CCD camera to obtain the display image of the LED display screen, obtains the LED brightness through the image, and obtains the correction coefficient from it. In practice, it is necessary to determine the coordinates of the light points in the image. To address this issue, the relationship between the position of the light points in the LED display and the coordinates in the image was analyzed, and a formula for calculating the brightness of the light points was derived. And an internal circuit of Field Programmable Gate Array(FPGA)for brightness correction was designed. Through experiments, the non-uniformity of LED display screens has been reduced from 6.506 to 2.923. The results show that this method is efficient, time-saving, and can significantly improve the brightness uniformity of LED display screens.