Light confinement in thin film organic photovoltaic cells

Microstructuring of polymer surfaces on optical spacers allows formation of reflective light traps. Such flexible reflectors can be combined with flexible polymer solar cells. We have demonstrated enhanced absorption using Lambertian and regular light reflectors, demonstrated via luminescence from fluorescent layers. Such light traps are suitable to use in combination with polymer solar cells incorporating transparent electrodes. The possibility to enhance the concentration of excited states and photogenerated charges through light trapping also helps to increase charge carrier mobility. These experimental results indicate that light confinement may be an alternative approach for boosting the efficiency of thin film conjugated polymer photovoltaics.