Friedrich-Alexander-Universität Erlangen-Nürnberg

Fabrication of Regular Micro- and Nanostructures

Fabrication of Regular Micro- and Nanostructures

Because of rapid progress concerning light extraction and color rendering, LED-light-sources have more and more developed into a real alternative for conventional ones in recent years. Still, current research projects aim at improving and optimizing the production process and luminous efficacy. Within the research project the generation and effects of micro- and nanostructures on different optically active surfaces are studied. The main focus is on active surfaces of phosphor based LEDs emitting white light.

Especially laser-based processes for direct and indirect structuring are being investigated. New photonic and chemical methods like laser-interference-lithography and self-assembling polymer layers give the possibility to realize structures with grating periods below the wavelengths of visible light. These processes are characterized by high flexibility and speed and thus, offer a cost advantage in the application-specific production of textured surfaces in small and medium-sized series, when compared to conventional methods.

The interaction of different kinds of phosphor and laser radiation of varying wavelengths and pulse energies has thoroughly been investigated. Generated test structures on LEDs led to a more homogeneous colour impression.

Roughened lens-structure generated in LED-phosphor by ArF-excimer-laser ( = 193 nm)
Different directional characteristics of an LED before and after micro structuring

Mission

SAOT provides an interdisciplinary research and education program of excellence within a broad international network of distinguished experts to promote innovation and leadership in the areas

Optical Metrology
Optical Material Processing
Optics in Medicine
Optics in Communication and Information Technology
Optical Materials and Systems
and Computational Optics.