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The global pandemic galvanized the development and deployment of ultraviolet-C (UV-C) technology. For decades, scientists have known about the disinfection powers of UV light. Now, light-emitting diodes (LEDs) are taking UV-C technology to a higher level. Adding LEDs to the process creates a safer and longer-lasting weapon to zap pathogens.

LEDs, which are semiconductor devices, generate a selected wavelength depending on their composition. For disinfection applications, UV-C LEDs should produce optimum wavelengths of around 260nm to 280nm. Wavelengths in this spectrum can inactivate pathogens such as bacteria and viruses.

The technology has gained momentum since the start of COVID-19, with designers finding new technology and innovation in developing products to combat the pandemic. These products can be found in hospitals, medical laboratories, senior care centers, police and fire stations, airports, transit stations, schools, office buildings, and hotels.

UV-C LEDs offer advances to traditional UV-C lamps. They consume less energy and require no warm-up time. In addition, UV-C LEDs are more compact, which allows more design options.

In this week's New Tech Tuesday, we'll look at UV-C LED products from Luminus Devices, Lumex, and Vishay Semiconductors.

Luminus Devices XST-3535-UV Surface Mount UVC LEDs are ideal for use in air and water purification, surface disinfection, medical device, appliance sterilization, and food and beverage preparation. XST-3535-UV LEDs are short wavelength, deep UV LEDs. The LEDs emit between 275nm and 286nm with a 60° angle and function in the 5V to 7.5V forward voltage range. XST-3535-UV LEDs come in a 3.5mm x 3.5mm compact form factor.

The Lumex LDM-LXF1017030UVC Evaluation Board with SML-LXF3535UVCC10 is the development tool of choice for the quick adaptation of UV-C LED into product development. The board's circuits provide constant current output and ensure each UV-C LED is protected. The plug-and-play board can connect to any power source to provide 8V to 9V DC evaluation power. The board offers a 275nm peak wavelength and includes 10mW radiant flux, 150mA maximum forward current, 0.7W power dissipation, and a 120° viewing angle.

Vishay Semiconductors VLMU35C Ultraviolet C LEDs are ceramic-based, low-power, surface-mount devices with a quartz window that's designed for a long lifespan. Typical applications include sterilization, medical application, and sensing of gases, germs, and DNA. The LEDs exhibit radiant powers in a wavelength range of 265nm to 285nm. They're available in 3.45mm x 3.45mm x 1.78mm dimensions. They're small in form but emit strong UV radiation during operation.

While UV-C technology has been around for more than a century, its unique disinfection ability has contributed significantly to the fight against the COVID-19 virus. Due to this, UV LEDs have become an integral part of the recovery effort during this global crisis.