ABSTRACT
Introduction Electroluminescence of organic molecules has been a well-known phenomenon since the mid-twentieth century. However, it was not until 1987, that organic light-emitting diodes (OLEDs), sometimes called organic light-emitting devices, became promising for practical applications, when Tang and van Slyke demonstrated the rst high-eciency device. Since this discovery, OLEDs have evolved from a scientic curiosity to a commercially viable technology incorporated into hand-held devices for bright, vibrant displays that oer beautiful colors and unmatched viewing angles. Furthermore, recent progress in OLED materials and manufacturing technologies suggests that signicant changes such as development of larger displays, specialty lighting, and even general lighting will be possible, once current challenges to longevity and cost are overcome. ese novel light sources, not only oer promise of energy eciency, but also, may enable entirely new approaches to room lighting design due to novel form factors; and for transparent and exible devices not accessible with other lighting technologies.
