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ieee oled abstract free download

OLED, or Organic Light Emitting Diodes, are an offshoot of existing conventional LED technology. LEDs are semiconducting light sources that function through electroluminescence—that is, they produce photons (aka light) by plopping electrons into little electron holes within the device's emissive layer. Basically, electricity goes in and light comes out thanks to a semiconductuctive material, rather than a white-hot metal filament like an old-school lightbulb.

OLED technology, first successfully implemented in 1987 by Kodak researchers Ching W. Tang and Steven Van Slyke, takes this same idea as LED, but flattens it. Rather than an array of individual LED bulbs, OLED uses a series of thin, light emitting films. This allows the OLED array to produce brighter light while using less energy than existing LCD/LED technologies. And since these light-emitting films are composed of hydrocarbon chains, rather than semiconductors laden with heavy metals like gallium arsenide phosphide, they get that "O" for "organic" in their name.

An OLED panel is typically composed of four primary layers: The substrate, which acts as the structural framework; the anode, which draws electrons; the cathode, which provides electrons; and the organic layer between. That organic layer is further divided into a conducting layer—which provides the "electron holes" that the electrons flowing through layer can snap into, shedding energy in the process—and an emissive layer where the light is actually produced. And if you want to start messing with producing actual color, it's just a matter of adding red-, green-, and blue-tinted plastic layers to the substrate.

There are additional flavors of OLEDs that are better for different kinds of devices. When a device only needs to display a static pattern with relatively slow refreshes—like the LCD readout of a calculator or e-ink displays of the Kindle Paperwhite—you can use something called a passive matrix OLED (or a PMOLED). These work by turning on voltage to specific areas of the film and leaving them on until the device refreshes its instructions.

Then there's active matrix OLEDs, like the AMOLEDs you might find in a smart phone. These are for high-definition applications that demand fast refresh rates, such as smartphone screens or HD televisions. AMOLED displays require a thin film transistor back-plane to actually drive each of the individual pixels, but this layer is just as flexible as the others, allowing for the development of rollable, foldable, transparent display panel prototypes.