Analysis of several new technologies for LED display applications

"Analysis of Several New Technologies for LED Display Applications" Colleagues in the LED industry and applications all know the advantages of LED display light efficiency. Power saving, green, and long life are the core values ​​of LED displays. Progress has made great contributions, and there are some deeper new technologies that affect the future development of LED displays. The 2017-2022 China LED display industry special survey and investment value forecast report shows that in addition to the advantages of long service life, high luminous efficiency, small size, light weight, environmental protection, safety and reliability, the LED semiconductor display light source also has a The obvious advantage is that because the LED starting voltage is consistent with the working voltage, there is no need to use a ballast. In this way, while saving cost and energy consumption, the response time of power on and off is also greatly shortened.

The development of LED in the market is very rapid, and it is very popular among users. The use of LED technology shows a lot of superior characteristics. The main characteristics are as follows. Now analyze the characteristics of China's LED display technology in 2017. Generally speaking, LED is a semiconductor solid light-emitting device that can emit ultraviolet light, visible light, and infrared light when a forward current is applied to the P-N junction.

The core of its light-emitting mechanism lies in the P-N junction. When a forward voltage is applied, the balance of the P-N junction is broken, and the holes in the P region enter the P-N junction to neutralize some of the original negative ions, and the electrons in the N region enter the P-N junction to neutralize the original part. Positive ions, which narrow the P-N junction, reduce the electric field of the P-N junction due to the external electric field, causing a reduction in the potential energy of the electrons, and the reduced potential energy is converted into electromagnetic energy and released in the form of photons. The more energy the electron reduces, the higher the energy of the released photon. With the in-depth study of related technologies, the luminous efficiency of LEDs is constantly improving, and ultra-high brightness LEDs will come out, which is bound to replace ordinary display screen electric light sources, and save a lot of energy and have no pollution.

According to the analysis of the characteristics of China's LED display technology in 2017, LED display technology presents eight major trends. LED display technology involves a wide range of areas. It is a combination of multidisciplinary technology and modern information technology. Its development presents eight major technological development trends. 1. Research on narrow-spectrum LED devices: the narrower spectrum of a single LED can realize the flexibility of combined LED spectrum, and can realize a larger color gamut space in LED display screens. It is a large application field and the technology to realize narrow-spectrum LED devices A breakthrough must be made in material epitaxy. 2. Vigorously expand the application field of LED display: promote the application of non-visual display systems, such as medical care, ecological agriculture, LED visible light communication, and the application of infrared LED and ultraviolet LED. This aspect is rich in content, and the application technology is developing rapidly .

LED display application technology focuses on the development of high-definition small-pitch display and high-definition bendable display technologies to realize high-definition LED TVs and high-definition foldable and wearable display devices. 3. The natural light LED display will be the ultimate goal: With the development of LED multi-spectral display, people will pay more attention to energy-saving display, healthy display and ecological display. Using similar sunlight display will be the best choice. That is, natural light led display can be realized by using LED technology, but many technical problems need to be solved. Seventh, white light LED devices will gradually turn to RGB combination mode: the use of RGB combination white light theoretically has higher light efficiency, and facilitates dimming, color adjustment, and color rendering of lamps, etc. Technically, it is necessary to focus on improving the light efficiency of green LEDs , RGB combination is likely to become the mainstream of ordinary display.

4. Improve the light color quality and color rendering characteristic value of LED light source: To improve the light color quality of LED light source, RGB multi-spectral combination, that is, multi-chip combination or multi-primary color phosphor combination, should be used to achieve a reasonable LED spectral distribution SPD , but also to control the main light color parameters, such as color tolerance, glare, photoelectric flicker, etc. The characterization of the color rendering of LED light sources is a long-term debate. LED light sources can realize the flexible combination of multi-spectrum. The color rendering characterization of any parameter is flawed. The ultimate characterization may be in the form of spectrum. Some experts proposed to use color gamut index (GAT) together with CRI to characterize the restoration of light to color.

5. Improve the energy efficiency of the LED display lamp: The energy efficiency of the LED lamp is currently composed of six parts: internal quantum efficiency, chip light extraction efficiency, packaging efficiency, phosphor excitation efficiency, lamp efficiency and power supply efficiency. Under certain boundary conditions, the theoretical value is 58%. At present, the energy efficiency of better lamps is only more than 30%, and there is still a lot of room for improvement. The above six items must reach more than 90%, which requires a breakthrough in technology. 6. In-depth research and development and application of intelligent LED display: the technical characteristics of intelligent display include open, distributed, remote control and telemetry, compatibility, interactivity, etc., which is the deep integration of display technology and information technology.

It involves a wide range of technologies, and the key technologies include the interface integration between the light-emitting module and the driving power supply. At present, there is an urgent need for a unified basic standard, and research, development, promotion and application should be carried out according to actual needs. 7. Innovative technology of LED display lamps: LED light sources and lamps are currently the top priority of the LED display industry. Technically, it is necessary to accelerate the innovation of lamp modeling and control functions. It needs to be adjusted, the light color can be changed flexibly, and the installation position is random. LED display technology has a lot of room for development, and it is necessary to further improve the energy efficiency and light quality of the whole lamp.

While actively promoting the innovation of lamps and lanterns in application, it is necessary to continuously expand the application field, such as smart LED display, non-visual display and high-definition display; in terms of technology, the ultimate goal is to achieve the natural light display, providing people with energy-saving, healthy , Comfortable display environment. .