Organic Light Sources for Polymeric Singlemode and Multimode Waveguides

Thin film devices like organic light emitting diode (OLED) and organic photovoltaic or organic photodiode (OPV or OPD) are more and more commercially used. Moreover, new fields of applications are signal sources and sinks in integrated flexible polymeric waveguide and sensor systems. Additionally, coherent light sources, such as organic thin film laser (OL), become more and more important in the field of sensor technology. Therefore, special optical requirements are placed on the integration of these elements into such systems. In this paper we want to discuss the fundamental integration concepts of coherent and non-coherent signal sources into polymeric multimode and singlemode waveguides. By varying the layer thickness d of each functional OLED layer forming a micro cavity, light coupling efficiencies ηc of up to 50% could be measured. We also demonstrate the OL integration via distributed feedback Bragg gratings and via Fabry-Perot resonator concepts leading to laser thresholds of about ≈ 10 µJ/cm². These results outline the OLED and OL integration into polymeric waveguides and emphasize the necessity of further investigations into resonator design and degradation effects.