Germicidal LEDs
Ultraviolet is outside the range of light visible to the human eye in the range of 100-400 nm. This is the short wavelength solar spectrum between X-rays and visible radiation. Different types of UV chips are used for disinfection, in the production of cosmetics, food, and forensic medical examination.
Produce ultraviolet chips additive on semiconductor materials. Usually gallium arsenide is used. It produces infrared light. The emission of UV diodes helps prevent the spread of coronavirus, which is why they are now often used in hospitals.
The principle of operation of UV LEDs for disinfection
The principle of operation of UV diodes has much in common with standard SMD chips. But here additives are responsible for the radiation characteristics:
- AIN, aluminum nitride;
- AlxGa1-xAs - gallium aluminum arsenide;
- InN india is a binary combination of nitrogen and indium;
- GaN (gallium nitride) - gallium and nitrogen.
The light source is a crystal with a p-n junction. Inside, the processes of recombination of electrons and the formation of photons take place. The radiation range depends on the specific material of manufacture and the type of chips. The most popular are diodes with a wavelength of 370-400 nm due to ease of production and affordable price.
Characteristics of diodes
UV germicidal LEDs have the following technical parameters:
- duration of work under normal operating conditions - 50,000 hours;
- operating current for weak and chips - 20 mA, for powerful elements - 400-700 mA;
- possible wavelength - from 100 to 400 nm;
- voltage 3-4 V;
- flux intensity - 500-4500 mCd;
- radiation angle - up to 120°;
- maximum heating - 60 C °;
- permissible operating temperature – from -20 С° to +100 С°.
The device operates at standard current from a conventional 220 V power supply.
Advantages and disadvantages
If you replace discharge lamps with LEDs in decontamination devices, this will provide the following benefits:
- power can be adjusted over a wide range due to the presence of a dimmer;
- due to the compact size of the chips, the radiation is accurately fixed on the disinfected object;
- the possibility of creating a source with an effective wavelength of 270 nm. This will provide high mechanical strength and reduce the weight of the installation;
- the device works without mercury;
- when compared with standard systems, the launch is instantaneous;
- diodes operate in the long-wave range, so the release of ozone is impossible;
- air exhaust pipes are not needed, the unit is water-cooled;
- some models are equipped with mixed wavelength LEDs.
Diodes make it possible to obtain a compact disinfection device with fewer restrictions when compared with standard germicidal lamps. Due to the power adjustment, the unit can be used in rooms where there are people, without a negative impact on health.
Among the disadvantages of UV chips are:
- adjusted coverage is often expensive;
- lower efficiency when compared with medium pressure lamps;
- paints suitable for lamps react to sunlight;
- UV light is focused only with special lenses;
- it is not possible to replace one of the damaged elements in all installations;
- in water-cooled systems, condensation may form inside the chamber. This will provoke the accumulation of microorganisms in the cooling system.
Recommended for viewing: 100 UV LEDs for 100 rubles
How to properly use UV LEDs
Improper operation of the LED lamp will not lead to the desired effect. In this case, the owner may have a false impression of efficiency. Also, do not forget about the unnecessary wear of the device and the consumption of electricity. One of the common mistakes when using the unit is incorrect placement without taking into account the movement of the air flow. In most cases, the line is formed by a door and a window.
Before purchasing and turning on the device, it is necessary to familiarize yourself with the characteristics and service life to evaluate the effectiveness. Make a schedule for switching on and off.
If there was a person with SARS in the apartment, the following steps must be performed for sterilization:
- Everyone must leave before the cleanup begins.
- Carry out wet cleaning.
- Ventilate the room for at least 15 minutes.
- Turn on the device for half an hour.
At the end, ventilate the room for 5 minutes. Repeat cleaning 1 more time during the day.
Scope of application
Until recently, UV LEDs were used in the same areas as ultraviolet lamps. But they benefit from compactness, a larger radiation range, and energy savings. One of the significant advantages is a long service life. UV diodes are used in the following areas:
- pharmacology. In the production of medicines;
- in nail salons. Ultraviolet lamps are effective in drying gel polish and building nails using helium formulations;
- production and industry. When working with composite compounds that polarize and harden under the influence of ultraviolet rays;
- the medicine. For disinfection of premises.
- banking industry. The lamp helps to determine the authenticity of banknotes, to read the bank marks applied to the paper.
- criminalistics. Used in operational activities to detect traces, body fluids and particles.
Applications for germicidal LEDs are added to the list every year. Many countries are conducting research and testing on the effects of ultraviolet radiation on health. Perhaps the rays will be used to counter cancer.
For home
It is recommended to purchase devices in the middle price range. Cheap lamps are not always safe. It is worth knowing how long to leave the lamp on, based on the size of the room. For example, indoors 20 m3 The lamp must be left on for at least 20 minutes.
By design, the devices are of closed or open type. Open placed on a tripod, wall or ceiling. Closed devices are less popular. Chips effectively fight viruses, kill fungus and mold in wet places, and disinfect storage areas for vegetables and fruits.
Conclusion
Disinfection LEDs effectively fight viruses and bacteria. But if you use the device incorrectly, you can harm your health. Before using UV diodes, you must read the instructions and safety regulations.
