What is an LED display? Background of led display.

LED luminous color and luminous efficiency is related to the production of LED materials and technology, the bulb is all blue light at the beginning, followed by phosphor, according to the different needs of the user, adjust the different light color, widely used red, green, blue, yellow four. Due to LED working low voltage (only 1.2~4.0V), can actively light and have a certain brightness, brightness can be adjusted by voltage (or current), itself and impact resistance, vibration resistance, long life (100,000 hours), so in large display equipment, there is no other display and LED display. The red and green LED chips or tubes are put together as a pixel to make a screen known as three-color or double primary color screen, and the red, green and blue LED chips or tubes are put together as a pixel screen called three-color screen or full color screen. If there is only one color is called monochrome or single primary color screen, indoor LED screen pixel size is generally 1.5-12 mm, often used to produce several different primary color LED tube core package into one, outdoor LED screen pixel size is 6-41.5 mm, each pixel is composed of a number of various monochrome LED, The common finished product is called the picture tube. The two-color picture tube is generally composed of 2 red and 1 green, and the three-color picture tube is composed of 1 red, 1 green and 1 blue. Whether using LED to make monochrome, two-color or three-color screen, to display the image needs to constitute the pixel of each LED luminous brightness must be able to adjust, the fine degree of adjustment is the display gray level. The higher the gray level is, the more delicate the displayed image is, the richer the color is, and the more complex the corresponding display control system is. Generally, the color transition of 256-level gray image is very soft, while the color transition boundary of 16-level gray image is very obvious. Therefore, color LED screen is currently required to make 256 to 4096 levels of gray.

LED light emitting materials applied to display screen have the following forms: (1) LED light emitting lamp (or single lamp) is generally composed of a single LED chip, reflective cup, metal anode, metal cathode, outsourcing with light transmission and light concentrating ability of the epoxy resin shell. One or more single lights (of different colors) can be used to form a basic pixel, which is used in outdoor displays due to its high brightness. The LED dot matrix module is composed of a number of chips to form a light-emitting matrix, encapsulated in a plastic shell with epoxy resin. Suitable for row and row scan drive, easy to form a high-density display, mostly used for indoor display. (3) SMT LED light (or SMD LED) is LED light paste welding form of packaging, can be used for indoor full color display, can achieve a single point of maintenance, effectively overcome the Mosaic phenomenon.