Extended by the LED and out of the fine application - UV LED production of a wide range of applications, market opportunities are enormous! From the point of view of the application of the most grounded gas, the UV light used in the printing field is almost completely covered, and the application will be further deepened after being covered, that is, from the UV mercury lamp and UV metal halide lamp gradually replaced by UVLED, is just around the corner.

The sunlight in nature contains ultraviolet radiation, which is the most effective and inexpensive source of air, water, surface purification, sterilization and bacteriostasis, and is one of the "gifts" given by nature to human survival. Through technical means, the correct use of ultraviolet (light), reasonable use of ultraviolet (light), ultraviolet (light) function to play to the extreme, become the well-being of mankind.

Ultraviolet (light):

Ultraviolet (light) is divided into three wavelengths from professional field according to wavelength.

1. wavelength: 315nm-380nm segment is long wavelength ultraviolet light, referred to as "UVA".

The 2. wavelength: 280nm-315nm segment is mid band ultraviolet light, referred to as "UVB".

The 3. wavelength: 280nm-315nm segment is short wavelength ultraviolet light, referred to as "UVC".

From the technical point of view, GaN is used as the luminous material in the common blue LED. However, the GaN band gap is 3.4 eV, and the radiation with the wavelength less than 370 nm inside the chip will be absorbed by GaN. Therefore, UV-LED mostly uses AlGaN as luminescent material. However, AlGaN LEDs require a larger band gap coating, resulting in a higher penetration dislocation density, resulting in a lower luminous efficiency. With the decrease of the peak wavelength, the external quantum efficiency of the UV-LED chip decreases. That is to say, in order to obtain shorter wavelength, the technology is more difficult, need to engage in the UV-LED chip manufacturers for application technology research has a continuous breakthrough process, at the same time, also need to discover the field of materials research, access to continuous convergence, it is possible to achieve a large area of UVLED, multi-field application depth, so that UVLED energy. It keeps serving mankind.

UVLED enters the disinfection, sterilization, bacteriostasis and even become the main means of the medical field, is slowly opening, taking advantage of this "door" has not yet fully opened into the full application of the opportunity, on sterilization, bacteriostasis, disinfection, share some of the "third eye" immature point of view, but also take the opportunity to the same trade, technology. Daniel does something to help.

Most of the known and existing applications use UVC-band ultraviolet light (280nm-315nm) to sterilize and inhibit bacteria. The broad spectrum of ultraviolet light can effectively kill various microorganisms, bacteria, even viruses, such as bacterial propagates, spores, mycobacteria, viruses, fungi, Rickettsia and mycoplasma. Body and so on.

Mechanism of ultraviolet sterilization

1. destroy genetic material.

Both bacteria and viruses reproduce and inherit on the basis of DNA (deoxyribonucleic acid) and RNA (ribonucleic acid). Ultraviolet light at UVC band can effectively break or damage the nucleic acid structure and function of cells and viruses. Nucleic acid absorption spectra are almost identical with the ultraviolet sterilization spectra. Nucleic acid is a number of nucleotide chains linked by phosphodiester in accordance with the principle of the pairing of pyrimidine and xanthine bases. These substances have strong absorption to ultraviolet light and make the maximum absorption in 250-270 nm band. It can be seen that when microorganisms are irradiated by 253.7 nm ultraviolet light, the absorbed light acts on nucleic acids. The energy of ultraviolet photons is absorbed by base pairs in DNA, destroying one or more chemical bonds in nucleic acid molecules, causing the decomposition or alteration of nucleoproteins or nucleic acids, thus causing bacteria or viruses to lay eggs. The Dysbiosis of white matter and enzymes results in their death or failure to reproduce their offspring for the purpose of sterilization and bacteriostasis.

2. affecting enzyme activity

Ultraviolet light emitted by UVLED can also affect the activity of many enzymes in bacteria and viruses, resulting in changes in the structure and function of protein molecules, interfering with the synthesis of proteins and nucleic acids, but also can reduce the toxicity of bacteria or viruses, reduce the activity and even death.

3. destruction of protein

If the UVLED radiation reaches 185 nm, so that the air O ramming ionization, the formation of oxygen free radicals and ozone, these two factors have a strong oxidizing effect, resulting in protein denaturation, bacteria and viruses lose metabolic capacity, resulting in bacterial or viral death.

Factors affecting UV disinfection efficacy

1. microbial species

The resistance of different microorganisms to ultraviolet light is also different. According to the relevant data, the order of resistance is fungal spores, bacterial spores, bacterial propagules, etc. The resistance of viruses to ultraviolet light is between spores and bacterial propagules.

2. radiation (radiation) dose

The radiation dose needed to kill the target microorganism must be used in disinfection. At present, there are many data supports, for example, the radiation dose should be more than 10 000 mu W (/ cm) when killing the germ propagule (the product of the intensity and time of the radiation) and sometimes the fungal spores should be increased to more than 600 000 mu W (/ cm) when sterilizing the target microorganism. In the case of unclear substances, the irradiation dose should not be less than 100 000 mu W. / cm. If the irradiation dose is insufficient, the disinfection effect will be affected.

3. exposure distance

The radiation intensity of ultraviolet light will increase and decrease with the distance between lamps and lanterns. The farther the ultraviolet radiation source is from the center, the lower the radiation intensity will become. The radiation intensity of ultraviolet light will decrease by about 10 mu W / cm per phase to 10 CM. The disinfection effect will be affected if the irradiation distance is not calculated accurately.

4. other factors

The degree of contamination and the smoothness of the contaminated surface, the location and frequency of the ultraviolet lamp, the temperature and temperature of the disinfection environment will all affect the disinfection object and disinfection effect.

According to CSA Research data, the technology level of semiconductor lighting in China has been improved rapidly, and the gap with the international advanced level has been further narrowed. Among them, the technology of deep ultraviolet LED is further improved. The continuous output power of 280nm deep ultraviolet LED at room temperature is over 20 mW, which is in the advanced level in the world. Many domestic companies and research institutes are also competing in deep ultraviolet LED, and UVC-LED sterilization and disinfection applications are gradually unfolding. Among them, the domestic listed company Hongli Zhihui has also joined in the implementation of the "LED + car networking" dual-main industry strategy, the main LED series products have grown steadily, while expanding LED production capacity and positively layout infrared security, ultraviolet and other sub-areas.

Industry insiders believe that 2017 is a year of rapid development of UVLED market and application, many enterprises involved in capital overweighting, will further promote the rapid development of this area of segmentation. CSA Research predicts that the external quantum efficiency of deep ultraviolet LEDs will increase to about 15% in 2017 and the output power will exceed 30 mW at room temperature, which will accelerate the penetration of ultraviolet LEDs in the field of disinfection and purification. The global market for UVLED in 2017 is expected to reach US$270 million, exceeding one-third of the total UV light source market, thus forming a confrontation with the UV mercury vapor lamp.