OLED technology and displays

Organic Light Emitting Diodes (OLED) are a different type of solid-state lighting source. An OLED device is typically formed in a sheet with emissive organic layer(s) located between a cathode and anode and deposited on a substrate. The substrate can be rigid such as glass or metal or flexible using a polymer plastic. The number of emissive layers depends on the desired light output of the device. OLED technology has great potential for new uses such flexible paper-thin OLED panels, transparent OLED panels and white OLED. White OLED was developed as device with extremely high power efficiency and long lifetime. The performance achieved was 64lm/W, and 10.000 hours of lifetime at initial luminance of 1000cd/m2 with light out-coupling technique. New technologies, such as sophisticated organic layer structure, were applied to the device. The device also exhibited good durability such as storage stability, which is important performance in practical use. We hope that this paper will show possibilities to practical use of OLED in different types of displays, lighting sources for illumination use, back light and others. From a recent environmental problem and energy supply circumstances, light sources of low energy consumption and eco-friendly are demanded. An enormous amount of research effort goes into the field. Organic light-emitting diode (OLED) is regarded as a powerful candidate because it is an area light source, can be driven at low voltage, and does not include a material which is harmful to the human body and environment like mercury. As a light source for illumination or backlight, a white light is usually required. To realize a white OLED device, plural light emissive materials such as blue, green, red are used generally.