Recent progress in thin film organic photodiodes

We review current developments in organic photodiodes, with special referen ce to multilayer thin film optics, and modeling of organic donor -acceptor photodiodes. We indicate possibilities to enhance light absorption in devic es by nanopatterning as well as by blending, and also discuss materials sci ence issues of nanostructure in blends and in vertically stratified multila yer devices. Our current best devices have external efficiencies of 30-50% in between 400-600 nm, and show fill factors of 0.54 illuminated under weak monochromatic light.