German Institute Shows Latest UV LED

The German Leibniz Federation Ferdinand-Braun-Institut (FBH) and its subsidiary UV photonics NT will be held in Berlin from April 22nd to 25th "2018 UV LED Technology and Application International Conference" displayed its latest UV LED.

With the improve of efficiency and output power, together with its small size, UV LEDs are used in more and more applications, including the disinfection of water, air and surfaces, and the curing of synthetic materials. UV LEDs can be quickly switched and dimmed, and heat dissipation is effectively radiated by the heat sink. Unlike mercury lamps, UV LEDs consist of non-toxic substances whose wavelengths can be flexibly adjusted over a wide spectral range.

They discovered a degradation mechanism during development: During the first few hours of operation, there will be electromigration of hydrogen in the UV-B LED structure, which is accompanied by a drop in the optical power of the device.

After a corresponding design adjustment, a UV-B LED with an L50 lifetime of 8,000 hours can be created. The optimization of the device has further improved the reliability of the LED and it is expected that the L50 lifetime will be significantly extended. In addition, the output power at 350mA can be increased to 30mW.

UV-LED lighting systems have three different wavelengths. Their brightness and irradiation intensity can be individually adjusted to determine optimal irradiation for structurally diverse plant secondary metabolites.

At the conference, FBH scientists will also demonstrate a compact diode laser source for the deep ultraviolet spectral range with an emission wavelength of 222 nm, where LEDs are difficult to achieve. The device converts light from a gallium nitride-based high-power diode laser into the ultraviolet spectral range by frequency multiplication (one-pass), and may be miniaturized. The wavelength-stabilized narrowband light source is particularly suitable for spectroscopy applications such as absorption spectroscopy and Raman spectroscopy for medical diagnostics and material analysis.