1. UV introduction

The wavelength of UV is from 10nm to 400nm, and it divided into different wavelengths: black spot uv curve of (UVA) in 320 ~ 400nm; Erythema ultraviolet rays or care (UVB) in 280 ~ 320nm; Ultraviolet sterilization (UVC) in 200 ~ 280nm band; To ozone ultraviolet curve (D) in 180 ~ 200nm wavelength.

2. UV features:

2.1 UVA characteristic

UVA wavelengths have a strong penetration that can penetrate most transparent glass and plastic. More than 98% UVA rays form the sunlight can penetrate the ozone layer and the clouds and reach the surface of the earth. UVA can direct the dermis of skin, and damage elastic fibers and collagen fibers and our skin. The UV light that its wavelength is about 365nm centered can be used for testing, fluorescence detection, chemical analysis, mineral identification, stage decoration and so on.

2.2 UVB characteristic

UVB wavelengths have medium penetration, and its short wavelength part will be absorbed by transparent glass. In sunlight, UVB rays form the sun is most absorbed by the ozone layer, and only less than 2% can reach the surface of the earth. In summer and in the afternoon will be particularly strong. UVB rays have erythema effect to human body. It can promote the formation of mineral metabolism and vitamin D in the body, but long-time or excessive exposure can tan the skin. Medium wave was used in fluorescent protein detection and more biological research, etc.

2.3 UVC band features

UVC wavelengths have the weakest penetration, and it can’t penetrate much of the transparent glass and plastic. The UVC rays form the sunlight is completely absorbed by the ozone layer. Shortwave ultraviolet radiation’s harm is very big, short time radiation can burn the skin, long or high strength still can cause skin cancer.

3. UV LED application field

In UVLED market applications, UVA have the largest market share, as high as 90%, and its application mainly involves UV curing, the nail, teeth, printing ink, etc. In addition, UVA also import commercial lighting.

UVB and UVC are mainly used in sterilization, disinfection, medicine, light therapy, etc.  UVB is given priority to medical treatment, and UVC is sterilization .

3.1 light curing system

The typical applications of UVA are UV curing and UV inkjet printing and the typical wavelength is 395nm and 365nm. UV LED curing light application included in curing UV adhesives that contain in the display screen, electronic medical, instrumentation and other industries; UV curing coatings contain building materials, furniture, home appliances, automobile and other industries of UV curing coatings; the UV curing ink printing and packaging industries;

Among them, the UV LED panels industry has become a hot. The biggest advantage is that it can provide no formaldehyde environmental protection board, and 90% energy saving, high yield, resistance to coin scratches, comprehensive benefit of economic advantages. This means that the UV LED curing market is a comprehensive application product and the whole cycle market.

3.2 light resin application field

UV-curable resin is mainly composed of oligomer, crosslinking agent, diluent, photosensitizer and other specific agent . It is crosslinking reaction and curing moment.

Under the irradiation of UV LED curing light, the curing time of uv-curable resin is very short that it don't need 10 seconds and it is much faster than the traditional UV mercury lamp in speed.

3.3. Medical field

Skin treatment: UVB wavelength is an important application of skin diseases, namely ultraviolet phototherapy applications.

Scientists found that about 310nm wavelength ultraviolet ray has strong shading effects to the skin, accelerate the metabolism of skin, improve skin growth force, which can be effective in the treatment of vitiligo, pityriasis rosea, polymorphous sunlight rash, chronic actinic dermatitis, so in the healthcare industry, ultraviolet phototherapy has been more and more used at present.

Medical equipment: UV glue adhesive have enabled medical equipment automated assembly easier.

3.4. The sterilization

UVC band by the short wavelengths of ultraviolet ray, high energy, can destroy microbes in a short time the body (such as bacteria,    virus, spores pathogens) DNA (deoxyribonucleic acid) in the cells or RNA (ribonucleic acid), the molecular structure of the cell cannot regenerate, bacteria and viruses lose self-replicating ability, so the UVC band can be widely used in products such as such as water, air sterilization.

Some deep UV applications on the market at present products include LED deep uv portable sterilizer, LED the deep ultraviolet toothbrush sterilizer, UV LED lens cleaning sterilizer, air sterilization, clean water, food sterilization and surface sterilization. With the improvement of people's safety and health consciousness, the demand of the products will be improved to a great extent, so as to create a mass market.

3.5. The military field

The UVC wavelength is belongs to blind ultraviolet wavelengths, so it has important application in the military, such as short distance,  secret communication interference and so on.

3.6. Plant factory filed

Enclosed soilless cultivation easy cause the toxic matter accumulation, and the substrate cultivation in the nutrient solution root secretions and rice husk degradation products can be degraded by TiO2 photo-catalyst , the sun's rays only contains 3% of uv light, facilities cover material such as glass filter out more than 60%, can be applied within the facilities;

Anti-season vegetables winter low temperature as low efficiency and poor stability, unable to meet the needs of facilities vegetable factory production.

3.7. Gemstone identification field

In Different kinds of gem stone, different colors of the same kind of gem stones and the mechanism of the same color, they have different the UV-visible absorption spectrum. We can use UV LED to identify gems and distinguish the certain natural gems and synthetic gemstones, and also distinguish some natural stones and artificial gem processing.

3.8. Paper currency recognition

UV identification technology is mainly test the fluorescent anti-counterfeiting mark and dumb light reaction of banknotes by using fluorescent or UV sensor. It can identify most of the counterfeit notes (such as washing, bleaching, and paste paper money). This technology developed very early and it is very common.