1. Divided into indoor, outdoor and semi-outdoor led video digital display wall according to the use environment; The indoor led screen area is generally from less than 1 square meter to more than ten square meters. Indoor LED display screens are used in indoor environments. Such display screens have moderate brightness, large viewing angles, close color mixing distance, light weight and high density, suitable for viewing at close distances. . The outdoor screen area is generally from a few square meters to tens or even hundreds of square meters, the dot density is relatively rare (mostly 2500-10000 dots per square meter), the luminous brightness is 5500-8500cd / square meter (different orientation, different brightness requirements), can be in the sun It can be used under direct light and the viewing distance is tens of meters away. The screen has good wind, rain and lightning protection capabilities. 
The semi-outdoor screen is between the outdoor and indoor, and has a high luminous brightness. It can be used outdoors under direct sunlight. The screen has a certain seal, and it is generally under the eaves or in the window. 2. Divided into single color, double primary color, and triple primary color by color (full color) Monochromatic means that the display screen has only one color of luminescent material, mostly single red, and yellow-green can also be used in some special occasions (such as funeral homes). The dual-primary LED display is composed of red and green LED lights. The 256-level gray-scale dual-primary display can display 65,536 colors (the dual-color screen can display three colors: red, green, and yellow). The full-color LED display is composed of red, green and blue LED lights, which can display white balance and 16,777,216 colors. 3. According to the control or use mode, it is divided into synchronous and asynchronous Synchronization means that the working mode of the LED display is basically equivalent to that of the computer monitor. It maps the computer image at the update rate of at least 30 fields / second corresponding to the map on the real monitor, usually with multi-grayscale color display Ability to achieve the effect of multimedia advertising. Asynchronous means that the LED screen has the ability to store and automatically play. The edited text and non-grayscale pictures on the PC are passed into the LED screen through the serial port or other network interface, and then the LED screen automatically plays offline. Generally there is no gray screen Degree display capability, mainly used to display text information, can be multi-screen networking. 4. Divided by pixel density or pixel diameter Since the specifications of the LED dot matrix module used in indoor screens are relatively uniform, they are usually divided according to the pixel diameter of the module: ∮ 3.0mm 62500 pixels / square meter ∮ 3.75mm 44321 pixels / square meter ∮ 5.0mm 17222 pixels / square meter