Advances in UV-A and UV-C LEDs and the applications they enable

Abstract

UV-A LEDs have seen efficiencies reach almost 70% and a substantial reduction in cost over the last few years. These trends have enabled UV-LED-based curing to become a mainstream application with most LEDs being driven at 1-2 A/mm2. At the same time novel applications, such as high-volume 3D Printing requiring higher power from UV LEDs have started to emerge. To address these applications, and to improve system speed in traditional applications, Luminus Devices has developed UV-A LEDs that can be operated at up to 4 A/mm2 which is the highest current density of any commercially available LED on the market. These next generation LEDs are very reliable and at 4 A/mm2 enable up to 74% higher power than LEDs driven at 2 A/mm2. This paper presents the performance characteristics of these nextgeneration LEDs, the novel and emerging applications they enable and provides a roadmap for future performance gains. UV-C LEDs are starting to become commercially viable but have low wall-plug efficiencies of 2%-4% and power levels reaching 100 mW. UV-C LEDs are not only replacing lamps but creating entirely new markets. The current status of UV-C LEDs is presented along with a discussion of the applications the LEDs will enable over the next 2-3 years.