JK FAR UVC Excimer Light Source(222nm)

Working principle

Excimer stands for “excited dimer” and is a dimer in the excited state. It refers to the transient molecule (nanosecond level) formed by the noble gases in the lamp excited by external voltage, which will radiate photons and decompose into atoms when it returns to the ground state with low energy. Excimer light source generally uses dielectric barrier discharge, and its far ultraviolet photon radiation mechanism can be described as follows: in dielectric barrier micro discharge, electrons with an average photon energy of several electron volts effectively splash krypton atoms and chlorine atoms. These excited krypton and chlorine atoms collide with the surrounding krypton and chlorine atoms to form excited krypton chloride excimer. When the excited krypton chloride excimer returns to the state of low energy, it will produce far ultraviolet radiation with narrow wavelength and relatively concentrated energy, with a wavelength of 222 nm which half peak is 2 nm. And it will quickly decompose into krypton and chlorine atoms. So the excimer lamps release and can be classified as quasi monochromatic light.

Dielectric barrier discharge (DBD) is a high voltage non thermal equilibrium alternating discharge. The discharge is driven by a high voltage of several thousand volts. The discharge is done by the micro discharge formed by a large number of filamentous irregular fast pulses discharge channel. The time of each micro discharge is very short, which is about 10ns, the channel radius is no more than 0.1mm, and the current density is as high as 0.1-1KA / cm².

When the external electric field voltage on the gas gap exceeds the breakdown voltage of the gas, the gas will be broken down and a conductive channel will be established. The space charge will be transmitted in the discharge gap and accumulated on the dielectric. At this time, the surface charge of the dielectric will establish an electric field, and its direction is opposite to the external electric field, so as to weaken the acting electric field and interrupt the discharge current. At the same position, only when the voltage rises again to the original breakdown voltage, the re breakdown and micro discharge will occur again.

Each micro discharge consists of three development stages

• Formation of discharge, that is, breakdown of electric field；

• Formation of continuous current pulse in the transmission process of electron in the gas；

• Excitation of the atom and molecular.

What are advantages of UV excimer lamp technology?

• Peak wave length: 222nm 

• No harm to human: safe and good for occupied or crowded indoor area when bypass band filter is used

• Proven technology: More than 100 researches and papers show the virus reduction effects.

• High effectiveness: 99.9% inactivation rate against all known pathogens

• Instant on/off: Reach 100% power in one second

• Environmental friendly: No mercury, no residual, no chemical

• Extensive allowable ambient temperature: -10 ~ -50 degree C (14-122℉)

• Low operation cost

• Low total harmonic distortion (THC)

• Meeting CARB regulation in terms of ozone content

• Large production capacity

• Flexible design capabilities for custom lamp development

• Optional dimming function

What are advantages of UV microplasma technology?

• Proved and matured technology: To date, available microplasma UV lamps use KrCl to monochromatically radiate at 222 nm peak wavelength which technology is available for decades and highly effective in pathogen inactivation;

• Human-safe: The emitted peak wavelength of 222nm is scientifically proved to be human-safe; 

• Long lifetime: The micro-plasma technology does not have electrode to kill the life of lamp;

• Monochromatical UV light: Peak wave length of 222nm means its energy and output concentrated;

• Collimated and uniform UV light: The planar geometry of microplasma lamps helps them emit collimated and spatially uniform beams with no “dark” point in line of UV light;

• High UV output efficiency: The presence of microcavities brings about the 5 to 10 times increase in the output intensity of these lamps, relative to conventional dielectric barrier discharge (DBD) sources;

• No negative in lifetime of lamp even with frequent power on & off;

• Instant on/off and instant hot restrike eliminating warm-up and reaching its peak performance in seconds;

• Extensive allowable ambient temperature range: -10-50℃ (14-122℉);

• Mercury free: The UV is generated with the micro-cavity excimer lamp technology;

• Eco-friendly: Made of fused silica and array of microcavity plasma on the silica with all components meeting ROHS and REACH compliance

• Low ozone generation: Meets CARB regulation;

• Low lamp surface temperature: Short-time touchable temperature with no skin burning

• Available power: modules up to 20W and combined several modules for higher wattage; 

• Multiple sizes: Module is easily incorporated with the existing ceiling fixtures with diameter of 4-inches, 5-inches, 6-inches and 8 inches and provides the versatility and convenience of replacement and supplement for sanitation purpose without additional cabling or hole-drilling;

• Good integration with existing lighting fixture: Planar and thin shape provides a large flexibility to be installed or replaced in the existing luminaires without hurting original designs or atmosphere; 

• Low ballast loss: The power factor of ballast is over 99% and it is an electronic ballast;

• Sturdy and durable ballast design with military graded electronic components and high quality extruded aluminum housing for maintenance free and low operation cost;

• Optional dimming with 0-10V function for controller with display screen, laptop or mobile phone APP for energy efficiency, smart control and remote control;

• No EMC issue: Compliance of CE Standard 55014;

• Optional supply voltage: 12VDC, 24VDC, 120~277Vac for American market or 220~240Vac for Asian and European market, 50/60Hz; 

• Optional supply voltage of 12VDC and 24VDC provides the potential off-line operation with battery-powered

What is the difference between 222nm and 254nm lamp technology?

Safety Tips and Precautions

Traditional disinfecting UV lamps are very effective against pathogens but they also emit light at harmful wavelengths and can only be used in unoccupied spaces. Excimer mainly emits light at a wavelength of 222 nanometers which deactivates viruses such as coronavirus and antibiotic-resistant bacteria. Many science researches and reports show that the wavelength of 222nm does not cause harm to humans so that it can be used in both unoccupied and occupied spaces around clock, highly increasing its effectiveness and usability against the spreading of infectious diseases. However it is a must to follow the guidelines of permissible exposure limit published by ACGIH (American Conference of Governmental Industrial Hygienists) and other local, national and international authorities, recommendations, regulations and standards. And do not light directly on humans.

Far-UVC 222 nm light is at the low range of the UV-C spectrum. Leveraging its germicidal abilities, this UV band is capable of inactivating harmful microbes at the size equal or larger than 0.1 um. The 222 nm wavelength is particularly effective in disrupting chemical bonds in dangerous or toxic gases and bio-toxins. Applying this observation in comparing the properties of 222 nm and 254 nm, the far-UV band could achieve higher UV absorption than conventional 254 nm. The possibility of photo-reactivation is also decreased due to the high energy of 222 nm.