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Company News | 2024/05/08

Some questions to help you know UVC LED

According to LED inside's "2018 Ultraviolet LED Application Market Report - Curing, Medical, and Sterilization", the output value of the UV LED market grew to US$223 million in 2017, and is expected to reach US$1.224 billion in 2022, with a compound growth rate of 2017-2022. 33%. In addition to the steady growth of the curing market, surface sterilization, still water sterilization, and flowing water sterilization are the main growth drivers in the next five years (2018-2022).

Today, let us talk about the core players in these major growth drivers: UVC-LED.

What is UV

First, let's review the concept of UV. UV, or Ultraviolet, is an electromagnetic wave with a wavelength between 10nm and 400nm. Different bands of UV can be divided into UVA, UVB, and UVC.

UVA:The wavelength is longer, between 320-400nm, and can penetrate clouds and glass into indoors and cars. It can penetrate into the dermis layer of the skin, causing sunburn. UVA can be further subdivided into UVA-2 (320-340nm) and UVA-1 (340-400nm).

UVB:The wavelength is in the middle, between 280-320nm, and will be absorbed by the ozone layer, causing sunburn and skin redness, swelling, heat and pain. In severe cases, it may cause blisters or peeling.。

UVC:The wavelength is between 100-280nm, but because the wavelength below 200 nanometers is vacuum ultraviolet light, it can be absorbed by the air. Therefore, the wavelength of UVC that can pass through the atmosphere is between 200-280nm. The shorter the wavelength, the more dangerous it is, but because it can be Barred by the ozone layer, only a small amount reaches the earth's surface.


UV sterilization mechanism

UV can destroy the DNA (deoxyribonucleic acid) or RNA (ribonucleic acid) molecular structure of microorganisms, causing the bacteria to die or be unable to reproduce, thereby achieving the purpose of sterilization.


UV sterilization band

According to the International Ultraviolet Association, "The UV spectrum (the 'germicidal' region) that is important for water and air disinfection is the range absorbed by DNA (or RNA in some viruses). This germicidal band is approximately 200-300nm."

Bactericidal wavelengths are known to extend above 280nm and are now generally thought to extend to 300nm, however this may change with more research. Scientists have proven that UV light with wavelengths between 280nm and 300nm can also be used for sterilization.


The most suitable wavelength for sterilization

There is a misconception that 254nm is the optimal wavelength for sterilization because the peak wavelength of low-pressure mercury lamps (determined solely by the physics of the lamp) is 253.7nm. In essence, as mentioned above, a certain range of wavelengths has a bactericidal effect. But it is generally believed that the wavelength of 265nm is the best because this wavelength is the peak of the DNA absorption curve. Therefore, UVC is the most suitable wave band for sterilization。


Why did history choose UVC LED?

Historically, mercury lamps were the only option for UV sterilization. However, the Minamata Convention on Mercury has officially entered into force in our country since August 16, 2017. The Convention requires that the production, import and export of specified mercury-containing products will be prohibited from January 1, 2021, and mercury lamps Also included in this list. Therefore, there is not much time left for mercury lamps, and UVC LED seems to be the only reliable alternative today.。

Of course, this change is also welcomed by everyone. The miniaturization of UVC LED components brings more imagination to application scenarios, many of which cannot be achieved with traditional mercury lamps. In addition, UVC LED also has many advantages such as fast startup, more switching times allowed, and battery power supply.

UVC LED application scenarios

According to LEDinside's "2018 Ultraviolet LED Application Market Report - Curing, Medical, and Sterilization", surface sterilization, still water sterilization, and flowing water sterilization will become the main growth drivers outside the curing market (2018-2022) in the next five years. According to different application scenarios, we may be able to see UVC LEDs in these applications in the future.:

Surface sterilization: high-frequency public contact surfaces such as medical equipment, maternal and infant products, smart toilets, refrigerators, tableware cabinets, crisper boxes, smart trash cans, thermos cups, escalator handrails, and automatic ticket vending machine buttons;

Still water sterilization: water dispenser water tank, humidifier, ice machine;

Flowing water sterilization: flowing water sterilization module, direct drinking water dispenser;

Air sterilization: air purifier, air conditioner.


How to choose UVC LED

You can make selections based on parameters such as optical power, peak wavelength, lifetime, and light emission angle.

Optical power: The available UVC LED optical power levels currently on the market range from 2mW, 10 mW to 100 mW. Different applications have different power requirements. Generally speaking, the optical power can be matched based on the illumination distance, dynamic demand or static demand. The greater the irradiation distance and the more dynamic the demand, the greater the required optical power.

Peak wavelength: As mentioned above, 265nm is the best wavelength for sterilization. However, considering that the average peak wavelengths of various manufacturers are not very different, optical power is actually the most important indicator of sterilization efficiency.

Lifespan: Consider the lifespan requirements based on the usage time of the specific application, and find the most suitable UVC LED. The most suitable one is the best.

Light emission angle: The light emission angle of lamp beads packaged with flat lenses is usually between 120-140°, and the light emission angle of lamp beads packaged with spherical lenses is adjustable between 60-140°. In fact, no matter what UVC LED light angle is chosen, enough LEDs can be designed to completely cover the required sterilization space. In scenes that are not sensitive to the sterilization range, a small light angle can make the light more concentrated, resulting in a shorter sterilization time.


Technical challenges facing UVC LED

Looking at the above, everything about UVC LED seems to be wonderful and “smells so good”!

But, like everything that develops, it faces growing pains. From epitaxy to chip to packaging, UVC LED is facing challenges.

For more information, inquiries or to book an interview please  Contact:
Shenzhen Hechuang Hitech CO., LTD.
Toll Free +86-755 2850 4426

Shenzhen Hechuang Hitech CO., LTD. is a National High-tech Enterprise, which has won a number of invention patent technology awards.  We focuses on the Research, Development, Production and Application of UVC-LED Technology. It adopts innovative technologies of revolutionary optics and fluid science, which can kill bacteria and viruses in 0.2 seconds, with a killing rate of 99.9999%. Hechuang Hitech provides safer, more efficient and more humanized sterilization module design for Water Air and Surface Disinfection products.