LED display parameters and terms:1. LED brightnessThe brightness of LED is generally expressed by luminous intensity, and the unit is candela CD; 1000ucd (micro candela) = 1 MCD (millicandela), 1000mcd = 1 CD. The light intensity of a single LED for indoor use is generally 500ucd-50 MCD, while the light intensity of a single LED for outdoor use is generally 100 mcd-1000 MCD, or even more than 1000 MCD.
2. LED pixel moduleThe LEDs are arranged into a matrix or pen segment and prefabricated into standard size modules. 8 * 8 pixel module and 8-character 7-segment digital module are commonly used for indoor display screen. The outdoor display pixel module has 4 * 4, 8 * 8, 8 * 16 pixels and other specifications. The pixel module for outdoor display screen is also called collecting tube bundle module because each pixel is composed of more than two LED tube bundles.3. Pixel and pixel diameter
Each LED light emitting unit (point) in the LED display screen that can be individually controlled is called a pixel (or pixel). Pixel diameter refers to the diameter of each pixel, in millimeters.For indoor display screen, generally one is a single LED with a circular shape. There are 3.0, 3.75, 5.0, 8.0 and so on, among which 3.75 and 5.0 are the most common.In the outdoor environment, in order to improve the brightness and increase the sight distance, one pixel contains more than two cluster LEDs; Since more than two cluster LEDs are generally not circular, the pixel diameter of solid outdoor display screen is generally expressed by the average distance between two pixels: 10, 11.5, 16, 22, 25.
4. Point spacing, pixel density and information capacityCenter distance or dot pitch of two pixels of LED display screen; The number of pixels per unit area is called pixel density; The amount of display content per unit area is called information capacity. The essence of the three is to describe the same concept: the point spacing reflects the pixel density from the distance between two pixels, and the point spacing and pixel density are the physical properties of the display screen; Information capacity is the unit of information carrying capacity of pixel density.The smaller the point spacing, the higher the pixel density, the more information capacity, and the closer the distance suitable for viewing.
The larger the point spacing, the lower the pixel density, the less the information capacity, and the farther the distance suitable for viewing.5. ResolutionThe number of rows and rows of LED display pixels is called the resolution of LED display. Resolution is the total number of pixels of a display screen, which determines the information capacity of a display screen.
6. LED panelThe LED pixel modules are assembled and arranged into a matrix according to the actual size, and equipped with special display driving circuit, DC regulated power supply, software, frame and external decoration to form an LED display screen.7. Grayscale
Grayscale refers to the degree of light and shade change of pixels. The grayscale of a primary color generally has 8 levels to 1024 levels. For example, if the gray level of each primary color is 256, the display color of the dual primary color screen is 256 256 = 64K color, also known as 256 color display screen.8. BicolorNowadays, most color LED displays are dual primary color screens, that is, each pixel has two LED tube cores: one is red tube core and the other is green tube core. When the red light die is on, the pixel is red, when the green light die is on, the pixel is green, and when the red and green die are on at the same time, the pixel is $. Red and green are called primary colors.
9. Full colorRed green double primary color plus blue primary color, three primary colors constitute full color. Because the blue tube and pure green tube core constituting full-color are more expensive, there are relatively few full-color screens at present.