LED display overview
The LED display is a flat panel display made by using a light emitting diode (LED) as an illuminant. LED has high photoelectric conversion efficiency, low driving voltage, easy interface with computer and long service life. The size of the screen can be seamlessly spliced as needed, making LED the first choice for flat panel display
LEDs are available in red, green and blue. Blue LEDs were the products that appeared in the late 1980s. The emergence of blue LEDs made full-color LED displays possible. With the continuous decline in the price of blue LED chips, full-color LED displays have gradually been applied. The bright future of LED display.
1) Full color--The luminous pixels that make up the LED display screen have three colors of red, green and blue. The combination of different gray levels of the three primary colors of red, green and blue can restore the color of nature and have rich expressive power. In theory, its color reproduction ability exceeds that of TV sets. As the price of blue chips declines, the production cost of full-color screens continues to decrease, which will become the development direction of LED displays.
2) Video screen—Video screen means that the LED screen has a point-to-point mapping relationship with the display of the control computer. The screen has grayscale control and is displayed synchronously with the computer monitor, so that an animation, a VCD, and a dedicated multimedia card can be played. Can play video signals, has a rich expressive power. The screen cannot be separated from the computer. In general, a computer controls a video screen.
Screen resolution
The resolution of the screen refers to the number of pixels that the screen has, and is represented by "number of columns X number of rows Y". At present, the TV ratio is 4:3 and 16:9. The main working modes of the computer are 640X480, 800X600 and 1024X768. The higher the resolution of the screen, the more content that can be displayed, the more delicate the picture, but the higher the resolution, the more expensive the cost. Therefore, the resolution of the screen should be designed according to the display requirements.
Gray level
Color reproduction is realized by different brightness combinations of three primary colors of red, green and blue. The brightness level of each primary color is called gray level. The degree of color reproduction depends on the gray level of the three primary colors. The higher the gray level. High, the more vivid the color reproduction.
The implementation of gray scale is achieved by controlling the duty cycle of the current of the LED tube. We have developed a mature 1024-level grayscale control technology and applied it to a full-color LED display, enabling the full-color screen to reproduce 16.67 million colors, which is at the leading level in China.
In addition, we use a unique g correction technology. If we use the equal-division brightening technique on the 1024 gray scales of the same primary color, that is, each gray scale is equally divided by linear law, which will result in blurred images and poor layering. After carefully analyzing the visual characteristics of the human eye, we first proposed and implemented a nonlinear step correction (ie, g correction) technique based on the LED's luminescence characteristics. This technique has a small difference in low-luminance region, and the number of gray levels is dense. When the temperature is gradually increased to a high-brightness area, the level difference is increased, and the number of gray levels is reduced, eventually resulting in a "level difference consistency" in visual effects, ensuring a better visual effect on the screen.