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Organic Light-Emitting Diodes Using Semi-Transparent Anode for Flexible Display

arjun — Fri, 07 Nov 2008 19:02:07 +0000

Abstract We studied EL properties of organic light-emitting diodes using a semi-transparent metal anode and conductive polymer instead of indium tin oxide. A metal anode and conductive polymer are thought to be more suitable for flexible organic light-emitting diodes than indium tin oxide. We fabricated organic light-emitting diodes using a semi-transparent metal anode and conductive polymer anode by vacuum-deposition method and spin-coat method, respectively. Ag thin film is one of optimal metals for the transparent anode because Ag has the lowest resistivity in all metals. The transmittance of composite anode can be improved by combining Ag thin film and an oxide semiconductor with high refractive index. We chose TiOz with a high rehctive index as a semiconductor. A conductive polymer read more

High-Resolution, Multicolor Organic LED Displays

arjun — Fri, 07 Nov 2008 18:53:27 +0000

Abstract The commercial potential of small format, bright, low power consumptialn displays drives Kodak’s investment in thin-film, low-molecular weight organic electroluminescenl devices. The prototypical small-molecule organic light emitting diode (OLED) consists of a transparent hole-injecting electrode, indium tin oxide (ITO), followed in sequence by the hole-transport layer :N,N-bis( 1 -Naphthyl)-N,N’- bis(pheny1)benzidine (abbreviated NPB), the electron tri~nsport layer tris(8- hydroxyquino1ine)aluinum (AlQ3), and a low work function metal electrode, MgAg( 10: 1)’. To achieve greatest market impact, we must develop efficient, high resolution, multicolor displaysbased on this technology. Consider a 5 cm diagonal VGA (640×480 columns by rows) display. Each read more

A novel use of LEDs to transmit audio and digital signals

arjun — Fri, 07 Nov 2008 18:48:09 +0000

Abstract THE SUPERIORITY OF LIGHT-EMITting diodes (LEDs) over incandescent lights, due to long life expectancy, high tolerance to humidity, low power consumption, and minimal heat generation, is well supported. LEDs are used in message display boards, signal devices, and many other means of illumination. One important characteristic of LEDs is that they are semiconductor devices capable of fast switching with the addition of appropriate electronics. That is, the visible light emitted by LEDs can be modulated and encoded with audio information for broadcasting. Therefore, in addition to their normal functions as indication and illumination devices, LEDs can be used as communication devices for transmitting and broadcasting audio and digital information. Hence, they can become part of read more

Wireless Optical Trasnsmissions with white colored LED for Wireless Home Links

arjun — Fri, 07 Nov 2008 18:41:18 +0000

Abstract In this paper, we propose the wireless optical communication system with white colored LEDs for wireless home link (WHL). The white colored LEDs have a high power output and are regarded as lamps for the next generation. In the proposed system, this device is used for wireless home link. The proposed system is suitable for private networks such as consumer communication networks. From numerical and simulation results, it is confifmed that the proposed system is available and the problems to be solved are made clear. Download Share and Enjoy: read more