LED display is a new type of information display medium, which is a flat display screen composed of light-emitting diode dot matrix modules or pixel units.
There are various categories of LED displays, which are generally classified in the following ways:
(1) Display device
LED digital display: The display device is a 7-segment digital tube, which is suitable for making electronic displays that display numbers such as clock screens and interest rate screens. LED dot matrix graphic display: The display device is a dot matrix display module composed of many evenly arranged light-emitting diodes, which is suitable for playing text and image information.
(2) Use environment
The indoor screen area is generally less than ten square meters, and the point density is high. It is used in non-direct sunlight or lighting environments, and the viewing distance is several meters away, and the screen body does not have the ability to seal and waterproof. The diameter of the light-emitting point is small, generally 3 to 8 mm in diameter. The outdoor screen area is generally from a few square meters to dozens or even hundreds of square meters, the point density is relatively thin (mostly 1000-4000 points/m2), and the luminous brightness is 3000-5000cd/m2 (different orientations, different brightness requirements), can be used in sunlight When used under direct sunlight, the viewing distance is tens of meters away, and the screen has good wind and rain resistance and lightning protection capabilities. The basic unit of outdoor screen light-emitting is pixels, and the center diameter of the light-emitting point of the pixel is relatively large, such as P10mm, P12mm, P16mm, P20mm, P24mm, P26mm, etc. The semi-outdoor screen is between the outdoor and the indoor. It has high luminous brightness and can be used outdoors without direct sunlight. The screen has a certain seal, usually under the eaves or in the window.
(3) Control or use mode
The synchronous mode means that the working mode of the LED display is basically equivalent to that of the computer monitor. It maps the image on the computer monitor in real time correspondingly at an update rate of at least 30 fields/s, usually with multi-gray color display capabilities. It can achieve the effect of multimedia advertising. Asynchronous (or communication) mode means that the LED screen has the ability of storage and automatic playback. The edited text and non-grayscale pictures on the PC are transmitted to the LED screen through the serial port or other network interface, and then the LED screen is automatically played offline. Generally, there is no multi-gray display capability, it is mainly used to display text information, and it can be connected to multiple screens.