What Is UV LED?
UV (ultraviolet) LED refers to a light-emitting diode (LED) that emits ultraviolet light.
Ultraviolet light possesses a shorter wavelength than violet light. This type of light is known for its harmful effects on human health with prolonged exposure, such as sunburn and skin cancer, but it also offers beneficial properties like sterilization. Ultraviolet rays are categorized into three types based on their wavelength ranges: UV-A (320~380nm), UV-B (280~320nm), and UV-C (200~280nm).
Uses of UV LED
Primarily used in industrial applications, UV LED penlights are also commercially available. Their applications span various industrial sectors.
Specific uses include:
- Atopic dermatitis treatment
- Photodynamic therapy (PDT) for cancer treatment using photosensitizers
- Mold prevention in refrigerators and air conditioners
- Sterilization of water purifiers
- Drying equipment for adhesives and paints
- Curing repair resins
In the medical sector, ultraviolet light’s immunosuppressive effects are leveraged, whereas in industry, it is used for curing UV-curable resins, essential for repairs and printing processes.
Principle of UV LED
UV LEDs produce light through the interaction between electrons and holes in the junction of n- and p-type semiconductors. Applying an electric field in the forward direction causes electrons to transition from the conduction band to the valence band, emitting light corresponding to the semiconductor’s band gap.
The wavelength of emitted light can be adjusted by altering the semiconductor material’s composition, primarily using aluminum gallium nitride for UV LEDs.
Other Information on UV LED
1. Deep Ultraviolet LED
Deep ultraviolet LEDs, emitting light with wavelengths between 100 to 280 nm, have been recognized as viable alternatives to mercury lamps due to their high energy and effectiveness against living organisms. They find applications in environmental sanitation, medical prevention of viral transmissions, and industrial processes like printing and coating, attributed to their low environmental impact, energy efficiency, and longevity.
However, their potential harm to human health necessitates protective measures to avoid direct exposure to deep ultraviolet light.
2. The UV LED Market
Since 2020, the demand for UV LEDs has surged, driven by heightened consumer awareness around sterilization. The market is expected to expand at a compound annual growth rate of 60% from 2019 to 2024, with hygiene products incorporating UV sterilization technologies spurring growth. As hygiene awareness continues to rise, so too will the demand for UV LEDs, which vary in price based on performance and are anticipated to become more affordable with advancements in production technologies.
3. Status of UV LED Development
Traditionally, mercury and metal halide lamps were the primary sources of ultraviolet light, despite their drawbacks, such as short lifespans and lengthy stabilization times. The advent of UV LEDs, especially those based on aluminum gallium nitride, has been met with challenges in achieving high brightness and output. Recent technological advancements, however, have significantly improved their performance, overcoming previous limitations related to light absorption by substrates through nanotechnology-based surface processing.