1. From the color: monochrome, two-color, three-color (full-color) LED display:

(1) Monochrome refers to the light-emitting material of only one color of the display screen, which is mostly single red.

(2) The two-color screen is generally composed of red and green LED diodes.

(3) Three-color (full-color) screen, composed of red, green (wavelength 570nm) and blue; and true color, composed of red, pure green (wavelength 525nm), blue.

2. According to the environment: indoor, outdoor and semi-outdoor LED displays:

(1) Between the semi-open air curtain indoor and outdoor, the brightness is high, and it can be used outdoors in the sun, and the screen body is sealed, generally on the roof or window.

(2) The indoor screen area is generally very small (more than ten square meters), the point density is high, in direct sunlight or ambient lighting, the viewing distance is a few meters away, because it is indoor, so it does not need to be open-air, and the screen body can not have the sealing and waterproof function. The indoor display dot matrix module is the main one, because the display brightness requirements for indoor use are not high;

(3) The outdoor display screen area is small dozens of square meters, hundreds of square meters or even thousands of square meters, the point density is sparse (mostly 1000-4000 points per square meter), the luminous brightness is 3000-6000cd/square meter (different directions, different brightness requirements), in direct sunlight conditions, the viewing distance is tens of meters, because it is outdoor, so it is necessary to use a waterproof box, and there is a good wind, rain and lightning protection ability on the screen.