UV LEDs

Ultraviolet Light Emitting Diodes, or UV LEDs, emit light in the UV spectrum which is usually less than 400nm. UV light is visible to the human eye and usually appears a bluey purple. The behaviour and characteristics of UV LED lights are influenced by several key specifications.

Mounting type, whether surface mount or through-hole, dictates how the LED is integrated into a circuit board, affecting heat dissipation and assembly. Peak wavelength, measured in nanometers (nm), determines the specific UV range emitted. Radiant flux, measured in milliwatts (mW), indicates the total optical power output, impacting the intensity of the UV LED light and its effectiveness in applications like sterilisation or material curing. Viewing angle represents the angle at which the light is emitted. Both narrow and wide beam angles are available to suit different applications.

What Types of UV LED Lights Are There?

• UVA (320-400nm) is similar to natural sunlight in our atmosphere.
• UVB (290-320nm) is popular for medical purposes.
• UVC (200-290nm) is the least common of the three. It is ideal for sterilisation and disinfection applications.

How Ultraviolet LEDs Work

Like all LEDs, UV LEDs convert electrical energy into light. However, they achieve this in the ultraviolet spectrum, which requires specific materials and processes.

UV LEDs are typically made from semiconductor materials like gallium nitride (GaN) or aluminum gallium nitride (AlGaN). The exact composition determines the wavelength of the emitted UV light. Similar to other LEDs, they contain a p-n junction, where electrons and holes recombine to produce photons.

Light Generation Process of a UV LED

• Electron-Hole Recombination: When a voltage is applied, electrons and holes move across the p-n junction.
• Photon Emission: As they recombine, they release energy in the form of photons in the ultraviolet range.
• Wavelength Control: The energy gap of the semiconductor material dictates the photon's wavelength, thus controlling the UV light's wavelength.

Key Components of a UV LED

• LED Diode: The core component, responsible for light emission.
• Substrate: Provides mechanical support and heat dissipation.
• Contact Layers: Facilitate electrical connections.
• Encapsulation: Protects the UV LED diode and shapes the light output.

The efficiency of UV LEDs, or the proportion of electrical energy converted into UV light, is heavily reliant on the materials and design of the diode. Semiconductor materials with a smaller band gap closer to the UV spectrum and optimised device structures improve the likelihood of photon emission over heat generation. Additionally, efficient heat management is essential to maintain both the performance and longevity of the UV LED diode.

UVC LEDs

UVC LED lights are a specific type of ultraviolet LED that emit light in the UVC range, typically between 200 and 280 nanometers. This range of UV light is highly effective at disinfecting and sterilising surfaces, water, and air by disrupting the DNA or RNA of microorganisms. Unlike traditional UV lamps, UVC LEDs are compact, energy-efficient, and mercury-free, making them a safer and more environmentally friendly alternative. They're increasingly used in applications requiring precise and targeted disinfection, such as water purification systems, medical sterilisation, and air purification devices.

UV LEDs vs UV Lamps

While both UV LEDs and UV lamps generate ultraviolet light, they employ different technologies and exhibit distinct characteristics. Here's a breakdown of their key differences:

Technology and Light Emission:

• UV LEDs: Use semiconductor materials to directly convert electrical energy into UV light.
• UV Lamps: Typically use mercury vapor discharge to generate UV light, requiring a warm-up period.

Energy Efficiency and Power Consumption:

• UV LEDs: Offer higher energy efficiency, consuming less power for the same UV output.
• UV Lamps: Generally consume more power and generate significant heat.

Lifespan and Durability:

• UV LEDs: Have a significantly longer lifespan and are more resistant to mechanical shock and vibration.
• UV Lamps: Have a shorter lifespan and are more fragile.

Safety and Environmental Impact:

• UV LEDs: Are mercury-free and emit no ozone, making them safer and more environmentally friendly.
• UV Lamps: Often contain mercury and may produce ozone, requiring careful handling and disposal.

Applications and Suitability:

• UV LEDs: Suitable for compact, portable, and precise applications, like water purification and medical sterilisation.
• UV Lamps: Better suited for large-scale applications like industrial curing and disinfection.

Avoid Common Mistakes When Purchasing UV LEDs

If you are looking to buy UV LEDs, avoid these common errors:

• Choosing the Wrong Wavelength: Ensure the UV wavelength of your ultraviolet LED matches your application (e.g., UVA for curing, UVC for sterilisation).
• Insufficient Power Output: Always check the power output specifications of the UV LED light to ensure it meets the requirements of your project.
• Incompatible Mounting Type: Consider the mounting type (surface mount vs. through-hole) based on your installation needs.

Industrial Applications for UV LEDs

Industrial Curing: UV LEDs rapidly cure adhesives, coatings, and inks in manufacturing processes, enhancing production speed and efficiency. They are used in printing, automotive, and electronics industries for precise and fast curing.

Cosmetic Curing: In the beauty industry, ultraviolet LEDs cure nail gels and other cosmetic products, providing a durable and long-lasting finish. These LEDs offer a safer and more controlled alternative to traditional UV lamps.

Forensics: UV LED lights are used in forensic investigations to detect bodily fluids, latent fingerprints, and other evidence that fluoresces under UV light. This allows for non-destructive analysis and improved evidence collection.

Security: UV LEDs are incorporated into security systems for counterfeit detection, document verification, and invisible marking. They aid in authenticating currency, passports, and other security-sensitive items.

Sterilisation: UVC LEDs are employed for disinfection and sterilization of surfaces, water, and air, disrupting the DNA of microorganisms. They are used in medical facilities, water purification systems, and air purifiers.

Plant Growth: UV LEDs, particularly those emitting UVA and UVB light, stimulate plant growth and enhance specific plant characteristics. They are used in indoor farming and horticultural applications to optimise plant development.

Your Trusted UV LEDs Supplier & Distributor

RS is a trusted supplier and distributor of high-quality UV LEDs in Australia, catering to diverse industrial and commercial needs. We offer a comprehensive range of UV LED lights, including UVC LEDs, alongside other optoelectronics. Buy UV LEDs from leading brands like Intelligent LED Solutions, Bivar, ams OSRAM, and many more.

For more information on delivery across Australia, please visit our delivery page.