LED display scanning mode and basic working principle
With the development of LED technology, the brightness of LED electronic displays is also increasing, and the size is getting smaller and smaller, which indicates that more LED electronic displays will become the general trend to enter the room. However, due to the improvement of LED brightness and pixel density, new and higher requirements are brought to the control and driving of LED screens. As far as the general indoor screen is concerned, the current common control method adopts the row-column sub-control mode, which is commonly referred to as the scanning mode. At present, the driving modes of the LED electronic display screen include static scanning and dynamic scanning. Static scanning is divided into two types. For static real pixels and static virtual, dynamic scanning is also divided into dynamic real image and dynamic virtual.
In the LED electronic display, the ratio of the number of lines lit at the same time to the number of lines in the entire area is called scanning mode. The scan is also divided into 1/2 scan, 1/4 scan, 1/8 scan, 1/16 scan and other driving methods. That is to say, the drive mode of the display screen is different, so the settings of the receiving card are also different. If the receiving card was originally used on a 1/4 scan screen and is now used on a static screen, then the display on the display will be lit every 4 lines. Generally, the receiving card can be set. After connecting the sending card, display screen, computer and other main components, you can enter the relevant software on the computer to set. So here we will first introduce the scanning mode and principle of the LED electronic display.
1. Scanning method of LED electronic display screen:
1. Dynamic scanning: Dynamic scanning implements “point-to-column” control from the output of the driver IC to the pixel points. Dynamic scanning requires a control circuit, and the cost is lower than that of static scanning, but the display effect is poor and the brightness loss is large. .
2. Static scanning: Static scanning is to implement “point-to-point” control from the output of the driver IC to the pixel points. Static scanning does not require control circuits, and the cost is higher than dynamic scanning, but the display effect is good, stability is good, and brightness is lost. The advantages of being smaller, etc.
2. Working principle of 1/4 scan mode of LED electronic display:
It is the time for each row of power supplies V1-V4 to be turned on 1/4 according to the control requirements in one frame of image. The advantage of this is that the display characteristics of LEDs can be more effectively utilized and the hardware cost can be reduced. The disadvantage is that in 1 frame of image, each row of LEDs can only display 1/4 of the time.
3. Classification according to the type of LED electronic display scanning method:
1. Scanning mode of indoor full-color LED electronic display: P4, P5 are constant current 1/16, P6, P7.62 are constant current 1/8.
2. Scanning mode of outdoor full-color LED electronic display: P10, P12 are constant current 1/2, 1/4, P16, P20, P25 are static.
3. The scanning mode of single and double color LED electronic display is mainly constant current 1/4, constant current 1/8 scan, and constant current 1/16 scan.