High-Efficiency Color and White Organic Light-Emitting Devices Prepared on Flexible Plastic Substrates
Blue, green and white organic light-emitting devices doped with fluorescent dyes have been successfully fabricated on high-refractive-index plastic substrates and characterized in terms of their electrical and optical properties. The devices consist of a wide-band-gap polymer emissive layer stacked with several small-molecule layers and were designed considering carrier balance, carrier confinement, dye-guest doping and optical characteristics. It was demonstrated that dye-doped polymer devices are effective for the improvement of color and emission efficiency. We demonstrated deep-blue-, bright-green- and pure-white light-emitting devices having external quantum efficiencies and color coordinates (x,y) of 6.0% (0.15,0.07), 5.5% (0.20,0.60) and 4.0% (0.33,0.33), respectively.