Ten major application areas of UV led

In recent years, with the continuous advancement of LED research and development, LED technology innovation and application fields have been continuously expanding, and the LED market has become increasingly broad. UV LED have gradually entered our field of vision, and some companies have participated in researching, improving, and applying UV LED ultraviolet lamps. For the general public, UV light of appropriate wavelength is also an essential light wave for our human body. So today, let's take a look at the main fields where UV LEDs are applied.

The so-called ultraviolet rays (Ultraviolet Rays/UV for short) refer to the invisible light rays beyond the visible light spectrum (red, orange, yellow, green, cyan, blue, and violet) of sunlight. UV rays are collectively referred to as radiation with wavelengths ranging from 10nm to 400nm in the electromagnetic spectrum. Depending on the wavelength, UV rays are generally divided into three bands: A, B, and C, as follows: UVA led ranges from 400 to 315 nm, UVB led from 315 to 280 nm, and UVC led from 280 to 100 nm. Specific applications vary according to different wavelengths.

In the UV LED market application, UV-A led holds the largest market share, reaching up to 90%. Its primary application market is curing, involving fields such as nail art, dentistry, and ink printing. In addition, UV-A led is also introduced into commercial lighting, which can make white clothes appear whiter. As for UVB led and UVC led, they are mainly applied in sterilization, disinfection, medical phototherapy, etc. Among them, UVB led is mainly used in medical treatment, while UVC led is used for sterilization and disinfection. Furthermore, UV LEDs are applied from paper currency recognition to light resin hardening, insect trapping, printing, and are developing towards markets such as sterilization, disinfection, biomedical treatment, anti-counterfeiting identification, air purification, data storage, and military aviation, mainly focusing on special lighting.

1. UV led in Application areas of light curing systems.

The typical applications of the UVA wavelength band are UV curing and UV ink printing, with representative wavelengths of 395nm and 365nm. UV LED light curing applications include UV adhesive curing in industries such as displays, electronic medical devices, and instruments; UV coating curing in industries such as building materials, furniture, home appliances, and automobiles; and UV ink curing in industries such as printing and packaging. Among these, the UV LED decorative panel industry has become a major hotspot. Its greatest advantage is the production of zero-formaldehyde environmentally friendly panels, with energy savings of 90%, high production volume, resistance to coin scratching, and comprehensive economic benefits. This indicates that the UV LED curing market is a comprehensive and full-cycle application product market.

Microelectronics industry - UV light curing applications: assembly of mobile phone components (camera lenses, earpieces, microphones, casings, liquid crystal modules, touch screen coatings, etc.), assembly of hard disk magnetic heads (gold wire fixation, bearings, coils, chip bonding, etc.), DVD/digital cameras (lens, lens bonding, circuit board reinforcement), motor and component assembly (wire, coil fixation, coil end fixation, PTC/NTC component bonding, protection transformer core), semiconductor chips (moisture-proof protective coating, wafer mask, wafer contamination inspection, UV tape exposure, wafer polishing inspection), sensor production (gas sensors, photoelectric sensors, fiber optic sensors, photoelectric encoders, etc.).

PCB industry LED UV light curing applications: component (capacitors, inductors, various plug-ins, screws, chips, etc.) fixation, moisture-proof potting and core circuit, chip protection, anti-oxidation coating protection, circuit board conformal (corner) coating, ground wire, flying wire, coil fixation, wave soldering through-hole mask.

2. Medical application field.

Skin treatment: An important application of the UVB wavelength band is in the treatment of skin diseases, namely UV phototherapy. Scientists have discovered that UV light with a wavelength of around 310nm has a strong melanotic effect on the skin, which can accelerate skin metabolism and enhance skin growth, thereby effectively treating photodermatoses such as vitiligo, pityriasis rosea, polymorphous light eruption, chronic actinic dermatitis, and actinic prurigo. Therefore, UV phototherapy is currently gaining increasing application in the medical industry. Compared to traditional light sources, UV LEDs emit pure spectral lines, which can maximize treatment efficacy. The UVB led wavelength band can also be applied in the field of health care. Exposure to UVB led radiation can induce photochemical and photoelectrical reactions in the human body, resulting in the production of various active substances. It is currently being used to regulate higher nervous function, improve sleep, and lower blood pressure. Furthermore, studies have shown that the UVB wavelength band can accelerate the production of polyphenols in certain leafy vegetables (such as red lettuce). These polyphenols are claimed to have anti-cancer, anti-cancer metastasis, and anti-cancer mutation properties.

Medical devices: UV adhesive bonding facilitates the economical and automated assembly of medical devices. Nowadays, advanced LED UV light source systems, capable of curing solvent-free UV adhesives in seconds, along with dispensing systems, provide an effective and economical method for achieving consistent and repeatable bonding during the assembly process of medical devices. The optimization and control of UV light sources are crucial for manufacturing reliable medical devices. The use of UV-curable adhesives offers numerous advantages, such as lower energy requirements, saving on curing time and space, increased productivity, and easier automation. UV adhesives are generally used for bonding and sealing medical devices, which demand the highest quality and reliability. Typical applications of UV adhesive curing in medical device assembly include bonding of: 1) different materials (or with different mechanical properties); 2) materials that are not thick enough for welding methods; 3) pre-produced sub-components.

3. Sterilization and disinfection field.

UVC wavelength ultraviolet light, due to its short wavelength and high energy, can destroy the molecular structure of DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) in the cells of microbial organisms (pathogens such as bacteria, viruses, and spores) in a short period of time. The cells cannot regenerate, and the bacteria and viruses lose their ability to self-replicate. Therefore, UVC wavelength products can be widely used for sterilization and disinfection of water, air, and other substances. Due to the advantages of UV-LEDs such as small size, they can be used as the light source for complete UV (ultraviolet) sterilization equipment, suitable for pre-packaging processes in large-scale production lines with various shapes and materials. They can also be used as the UV (ultraviolet) light source for indoor air sterilizers, suitable for indoor air sterilization and disinfection in homes, public places, and other indoor areas. They are also applied to various household appliances such as disinfection cabinets and microwave ovens.

Currently available deep ultraviolet (UV) application products on the market include LED deep UV portable disinfectors, LED deep UV toothbrush sterilizers, deep UV LED contact lens cleaning and sterilizers, air sterilizers, water sterilizers, and food and surface sterilizers. With the increasing awareness of people's safety and hygiene, the demand for these products will significantly increase, thereby creating a large-scale market.

4. Military field.

Since the UVC led band falls within the solar-blind ultraviolet spectrum, it also holds significant military applications, such as short-range ultraviolet secure communication, UV jamming, and UV warning technology.

Ultraviolet (UV) communication: Ultraviolet communication is a novel communication method with immense development potential. It possesses numerous advantages not found in other conventional communication methods, such as low eavesdropping rate, high anti-interference capability, low bit resolution, and all-weather operation. Therefore, it has garnered widespread attention from departments that demand high confidentiality and mobility in communication.

Ultraviolet (UV) jamming: The emergence of UV dual-color guided missiles inevitably leads to the development of infrared-UV dual-color jamming technology. The key to UV jamming is to develop a propellant with strong enough UV radiation, which can be filled to produce jamming shells with UV jamming capabilities.

Ultraviolet (UV) Warning: The ultraviolet (UV) warning device detects targets by detecting UV radiation in the exhaust plume of missiles. It lists the exhaust plume radiation characteristics of missiles using different fuels at low altitudes. It relies on active warnings that operate through radar, as well as passive warnings primarily including infrared, laser, and ultraviolet (UV) warnings.

5. Plants growth field.

According to Liu Wenke, a researcher from the Institute of Agricultural Environment and Sustainable Development, Chinese Academy of Agricultural Sciences, closed soilless cultivation is prone to the accumulation of autotoxic substances. However, TiO2 photocatalysis can degrade root exudates and rice husk degradation products in the nutrient solution of substrate cultivation. Solar light contains only 3% ultraviolet light, and more than 60% is filtered out by facility covering materials such as glass, making it impossible to apply within the facilities. The low temperature and limited sunlight during winter in off-season vegetable cultivation result in low efficiency and poor stability, which cannot meet the needs of industrialized production of facility vegetables. There is an urgent demand for the development of artificial light TiO2 photocatalytic systems suitable for soilless cultivation in facility horticulture, especially for use in plant factories, with great commercial potential. As of June 2015, China has established more than 80 plant factories and cultivated hundreds of thousands of hectares of multi-span greenhouses.

6. Application areas of oil fume purification equipment.

According to the report from Haining Yaguang, the UV led photolysis oxidation oil fume purification system is currently the most advanced photolysis oxidation oil fume purification system in China. In this purification system, a specially made uvc led tube containing 185nm+254nm plays a core role. It can decompose oil and grease as well as odors in kitchen air, and it has the advantages of no secondary pollution, reduced fire hazards, small size, light weight, and significantly reduced maintenance costs.

7. Application areas of exhaust gas treatment.

According to reports, the total VOCs emissions from China's textile industry account for about 30% of the total industrial VOCs emissions. VOCs are one of the precursor substances for haze generation and an important component for the formation of PM2.5. The photocatalytic oxidation treatment of VOCs using UV LED as a photocatalytic light source is superior, with advantages such as small size, high catalytic activity, stable chemical properties, low cost, and non toxicity, and has a wide range of application prospects.

8. Gemstone appraisal field.

Different types of gemstones, the same gemstone of different colors, and gemstones of the same color with different coloring mechanisms all have different UV visible absorption spectra. Although some optimized gemstones have the same color as their corresponding natural gemstones, their absorption spectra may differ due to differences in coloring mechanisms or coloring substances. UV LED can help identify gemstones and distinguish between certain natural gemstones and synthetic gemstones. It can also distinguish between certain natural gemstones and artificially processed gemstones through ultraviolet light irradiation.

9. Banknote recognition.

UV led recognition technology mainly uses fluorescent or UV sensors to detect the fluorescent imprint anti-counterfeiting mark and matte reaction of banknotes. This type of recognition technology can identify most counterfeit currency (such as washed, bleached, pasted banknotes). This technology was developed earliest, most mature, and widely used. It is not only used in ATM deposit recognition, but also in financial instruments such as cash counters and validators. Generally, fluorescence and purple light are used for comprehensive reflection and transmission detection of banknotes. Identify the authenticity of paper currency based on its different absorption and reflectivity of ultraviolet rays compared to other types of paper. Quantitative identification can also be performed on banknotes with fluorescent marks.

10.  Application areas of UV resin curing.

UV led curable resin is mainly composed of oligomers, crosslinking agents, diluents, photosensitizers, and other specific additives. It uses ultraviolet light to irradiate polymer resin, causing cross-linking reaction and instant curing. Under the irradiation of UV LED UV curing machine, the curing time of UV cured resin does not need as long as 10 seconds, it can be cured in basically 1.2 seconds, which is much faster than traditional UV mercury light curing machine in terms of speed. At the same time, it is also more ideal in terms of heat than UV mercury lamps. By adjusting the various components of UV curable resin, products that meet different requirements and applications can be produced. At present, UV curable resin is mainly used for wood floor coating, plastic coating (such as PVC decorative panels), photosensitive ink (such as plastic bag printing), electronic product coating (marking and circuit board printing), printing polishing (such as paper and playing cards polishing), metal parts (such as motorcycle parts) coating, fiber optic coating, photoresist and precision parts coating.