Organic Light Emitting Diodes (OLEDs)

Abstract

This paper gives the brief analysis of Organic Light Emitting Diodes (OLED) .OLED is a special 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 made of 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 as 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/m ² 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 the practical use of OLED in different types of displays, lighting sources for illumination, back light and others. In the recent environmental problem and energy supply circumstances, light sources of low energy consumption and eco-friendly are in demand. An enormous amount of research effort are going on in this area. Organic light-emitting diode (OLED) is regarded as a powerful light source because it  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.