Typical application mode of UV LED
High-speed rail car air disinfection
Rail transit has become one of our most important modes of travel. However, due to the relatively closed environment and densely populated compartments, it is very easy for us to be infected with bacteria and viruses and mutual infection. Therefore, air disinfection for rail transit is effective in blocking the spread of viruses and bacteria and reducing the spread of viruses and bacteria. The risk of infection is important.
In 2020, Zhongke Lu’an Semiconductor Technology Research Institute and CRRC Group signed a strategic cooperation agreement. The two parties cooperated to discuss the installation and trial operation of UVC LED sterilization devices on some high-speed rail cars. This will be the first domestic application of deep ultraviolet sterilization. Rail transit scene. At present, the project has completed the installation and commissioning of samples.
The main product in this project is UVC LED sterilization module. Sterilization modules are installed at the air intake and return air vents of the high-speed rail compartment air conditioners. This project will simulate the air flow at the air intake and return air vents, and design the structure, light distribution and quantity of the sterilization modules on this basis. After testing and calculating the application of the sample, the specific application effects are as follows: the air inlet speed of the air conditioner is 3.7m/s, and the wind speed of the return air outlet is 3.0m/s. % Is the air outside the car. Each section of the air inlet duct uses 4 UVC LEDs for sterilization, and the light power of each lamp is ≥500mW, calculated on the basis of the ultraviolet radiation dose required to kill 90% of Staphylococcus albicans, it takes about 20 minutes to complete the sterilization of the entire cabin air; each return air The road uses 3 UVC LED lamps for sterilization, and the light power of each lamp is ≥500mW. Based on the ultraviolet radiation dose required to kill 90% of Staphylococcus albicans, it takes about 33 minutes to complete the entire compartment air sterilization.
Air conditioning sterilization module application
This project is to use the UV LED sterilization and disinfection module in the household air-conditioning system. The key components of the deep-ultraviolet sterilization module are all domestically produced. They are produced by the UV upstream chip company Shanxi Zhongke Lu’an UV Optoelectronics Technology Co., Ltd., the midstream packaging company Shanxi Huawei UV Semiconductor Technology Co., Ltd., and the module company Qingdao Haidawei Health Technology Co., Ltd. Jointly developed by Haier, a terminal home appliance company.
This deep-ultraviolet sterilization module is commonly used in the "Thor" series of Haier air conditioners. When the air conditioner is working, the user activates the built-in ultraviolet sterilization module through the health button on the remote control to physically sterilize the indoor air.
In addition, the new "Jinxin Guardian" robot newly launched by Zhongke Lu'an is equipped with a deep ultraviolet LED disinfection module independently developed by Zhongke Lu'an. With UVA + photocatalyst, high-efficiency filter and other technologies, it can achieve 500-1000㎡/ h's large-space air disinfection processing capacity. At present, the product has obtained the sanitation certificate on the national disinfection product online filing information service platform. It can be widely used in large spaces such as airports, high-speed railway stations, large stadiums, conference centers, and civil administration centers. Air disinfection application.
Sterilization and disinfection applications in consumer products
At present, personal and household consumer products are the most used for UV LED sterilization and disinfection, including diversified forms such as disinfection kits, disinfection cups, and toothbrush boxes. Application scenarios are becoming more abundant, ranging from sterilization kits, maternal and child products, UVC sterilization flashlights, to UVC water purifiers, UVC sterilization robots, etc. Deep ultraviolet LED disinfection, sterilization, and purification are expected to gradually evolve from high additional functions to home appliances, home appliances, etc. Standard functions in kitchen and bathroom, consumer electronics, automotive and other application fields. Product performance has been continuously improved, combined with auxiliary functions such as intelligent voice, infrared sensing, remote control, direction recognition, light output detection, etc., to improve the safety of UVC LED products and optimize the product use process.
main problem
Core technology needs to be broken through
As the current level of UVC LED chip and device technology still needs to be further improved, the light radiation efficiency is still low, resulting in the price of UV LED products with the same effect is generally 2-5 times that of mercury lamps even in some low-power applications that can meet the demand. . Therefore, the application and promotion of UV LED sterilization and disinfection products firstly depends on the further improvement of the technical level. The average level of UVC LED external quantum efficiency is about 1-3%, and BOLB's external quantum efficiency is about 6.5%. Compared with the mature GaN-based blue LEDs and AlGaN-based near-ultraviolet LEDs, the light output power and quantum efficiency of UVC LEDs are still far from satisfactory. There is an urgent need for high-power deep ultraviolet solid-state light sources.
The progress of UVC LED packaging technology and technology is related to the light radiation efficiency and life of the device, and high-density inorganic packaging materials and forms are the development trend. Blue LED packaging materials and forms are basically suitable for UVA LED packaging, but ceramic substrates, inorganic packaging, hermetic packaging, and improving heat dissipation and light extraction efficiency for UVC LEDs are the focus and development direction of the industry.
The application plan is not mature yet
The UVC LED technology scheme for sterilization and disinfection is not yet mature, and the application data needs to be further accumulated. The conventional ultraviolet light source used for sterilization and disinfection has a fixed wavelength (253.7nm), and the spatial light distribution of the light source is uniform. UVC LEDs have different light-emitting principles from traditional ultraviolet mercury lamps. The light source shape, peak wavelength, spectral distribution, spatial distribution, power supply drive, heat dissipation requirements, secondary light distribution, and application systems are very different.
In addition, the application integration technology and engineering application problems of UVC LEDs have yet to be resolved. UVC LED is still in the initial stage of product introduction, and is gradually opening up the application market for water and air purification, sterilization and white goods. Its luminous power, electro-optical conversion efficiency and life span are not satisfactory. Further development requires the application of key core technologies. And practical and engineering problems, to promote the perfection and maturity of UVC LED related products as soon as possible.
Current standards and testing methods are missing
At present, domestic and foreign industry standards for UVC LED products have not been introduced, which is also a key factor affecting the sound development of the UVC LED industry.
Standard formulation needs to be gradually carried out as the market opens. The current relevant standards for ultraviolet disinfection products all revolve around traditional ultraviolet light sources, and ultraviolet LED disinfection products have certain standard blanks in terms of photoelectric parameters, lifespan, and uniformity. The UV LED application market is segmented, and the standard system has a wide range of fields.
The continuous development of UV LED technology and the market is facing a series of technical problems in measurement and detection. For example, traditional ultraviolet probes have a single corresponding band, and most of them only respond to specific wavelengths of ultraviolet radiation (253.7nm, 365nm), while ultraviolet LEDs have a large radiation bandwidth and a large difference in the spectral sensitivity curves of the probes, causing problems such as measurement traceability and calibration difficulties, which leads to measurement As a result, the error is large. Ultraviolet LEDs need to be gradually developed and formed in combination with their own spectral characteristics of sensor probes, standard light sources, and calibration methods, especially the measurement and testing of UVB and UVC band LEDs are technical difficulties.
Application system security measures need to be strengthened
Photobiological safety is an important issue that needs to be clarified clearly in market promotion. In the market, due to improper operation of UV sterilization products, news that harms the human body is common. Therefore, the safety design of UV products is particularly important. This requires companies to combine different application scenarios when designing products, and avoid harm to the human body caused by misuse through humanized design such as intelligent control and infrared induction. This requires companies to combine different application scenarios when designing products, and avoid harm to the human body caused by misuse through humanized design such as intelligent control and infrared induction. Therefore, in the process of application and promotion, it is necessary to first comprehensively publicize and popularize the photobiological safety of ultraviolet LED products to improve the ability of consumers to identify products.
In addition, for the application of direct ultraviolet rays, the materials need to have anti-ultraviolet requirements, so the impact of ultraviolet radiation on the end product materials should be considered when the product is applied.
Concluding remarks
Since 2020, the new crown epidemic has continued to repeat, further stimulating the development of the UV LED disinfection industry. The development of the deep-ultraviolet LED industry is increasingly returning to rationality. The enterprise shifted from rapid investment and expansion to product research and development and market cultivation. Deep ultraviolet LEDs have effectively verified the inactivation effect of the new crown virus; ultraviolet LED sterilization products have changed from low-power consumer products to high-power disinfection products; Expansion of premises; Demonstration projects of sterilization and disinfection engineering have gradually landed.
The potential of the UV LED disinfection market is constantly being tapped. The combination and joint development of UV LED disinfection products and application scenarios requires close cooperation between the upper, middle and lower reaches of the cross-field industrial chain, and the coordinated operations of chips, packages, modules, integrated applications and other links. It requires the active participation of production enterprises, testing institutions, research institutes, certification and market management institutions and other entities.
