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OLED

An organic light emitting diode (OLED), also organic electro luminescent device (OELD), is a light-emitting diode (LED) whose emissive electroluminescent layer is composed of a film of organic compounds. This layer of organic semiconductor material is formed between two electrodes, where at least one of the electrodes is transparent.

Such devices can be used in television screens, computer monitors, small, portable system screens such as cell phones and PDAs, watches, advertising, information and indication. OLEDs can also be used in light sources for general space illumination, and large-area light-emitting elements. Due to the younger stage of development, OLEDs typically emit less light per unit area than inorganic solid-state based LEDs which are usually designed for use as point-light sources.

In the context of displays, OLEDs have certain advantages over traditional liquid crystal displays (LCDs). OLED displays do not require a backlight to function. Thus, they can display deep black levels and can be thinner and lighter than LCD panels. OLED displays also naturally achieve higher contrast ratios than either LCD screens using cold cathode fluorescent lamps (CCFLs) or the more recently developed LED backlights in conditions of low ambient light such as dark rooms.


Advantages

The different manufacturing process of OLEDs lends itself to several advantages over flat-panel displays made with LCD technology.

Although the method is not currently commercially viable for mass production, OLEDs can be printed onto any suitable substrate using an inkjet printer or even screen printing technologies,[45] they could theoretically have a lower cost than LCDs or plasma displays. However, it is the fabrication of the substrate that is the most complex and expensive process in the production of a TFT LCD, so any savings offered by printing the pixels is easily cancelled out by OLED’s requirement to use a more costly P-Si (or LTPS) substrate – a fact that is born out by the significantly higher initial price of AMOLED displays than their TFT LCD competitors. A mitigating factor to this price differential going into the future is the cost of retooling existing lines to produce AMOLED displays over LCDs to take advantage of the economies of scale afforded by mass production.

Use of flexible substrates could open the door to new applications such as roll-up displays and displays embedded in fabrics or clothing.

OLEDs can enable a greater artificial contrast ratio (both dynamic range and static, measured in purely dark conditions) and viewing angle compared to LCDs because OLED pixels directly emit light. OLED pixel colours appear correct and unshifted, even as the viewing angle approaches 90 degrees from normal. LCDs filter the light emitted from a backlight, allowing a small fraction of light through so they cannot show true black, while an inactive OLED element produces no light and consumes no power.

OLEDs can also have a faster response time than standard LCD screens. Whereas LCD displays are capable of a 1ms response time or less[46] offering a frame rate of 1,000 Hz or higher, an OLED can theoretically have less than 0.01 ms response time enabling 100,000 Hz refresh rates.

http://en.wikipedia.org/wiki/Organic_LED#Advantages

Technology demos

In May 2007, Sony publicly unveiled a video of a 2.5-inch flexible OLED screen which is only 0.3 millimeters thick.

On May 24, Sony unveiled what it is calling the world’s first flexible, full-color organic light emitting diode (OLED) display built on organic thin-film transistor (TFT) technology. OLEDs typically use a glass substrate, but Sony researchers developed new technology for forming organic TFT on a plastic substrate, enabling them to create a thin, lightweight and flexible full-color display. The 2.5-inch prototype display supports 16.8 million colors at a 120 x 160 pixel resolution (80 ppi, .318-mm pixel pitch), is 0.3 mm thick and weighs 1.5 grams without the driver.

According to Sony, which plans to release a new line of miniature TVs this year and is bolstering efforts to develop next-generation flat-panel OLEDs, this new technology will lead to the development of thinner, lighter and softer electronics.

The company is scheduled to present the results of its research at the SID 2007 International Symposium now underway in the US.

http://pinktentacle.com/2007/05/flexible-full-color-organic-el-display/

Samsung’s 14-inch transparent OLED laptop

If you thought the XPERIA Pureness was wild with its meager 1.8-inch transparent screen, wait’ll you get a hold of Samsung Mobile Display’s prototype 14-inch notebook — complete with what’s being touted as the world’s first and largest transparent OLED prototype. When the thing is off, the panel is up to 40 percent transparent (as opposed to the industry average of below twenty-five percent). Not much more to say about it (we’ll let you know as soon as our friends from Korea tell us more), but there is plenty to see: so get a load of the video after the break.

http://www.engadget.com/2010/01/07/samsungs-14-inch-transparent-oled-laptop-video/

Sony OLED 3D TV eyes-on

Sony is showing off its 24.5-inch OLED television here at CES, and we have to admit to being blown away once more by the sheer vibrancy and clarity of the output. The jump from the 15-inch panels that are still very sparsely available in retail channels is most welcome. We can totally envision spending our happily ever after with one of these screens serving all of our visual needs, 3D or otherwise. Sony’s reps couldn’t tell us when these will make it to market, but the pics below should whet appetites appropriately.

http://www.engadget.com/2010/01/07/sony-oled-3d-tv-eyes-on/

Avec tous les avantages de la technologie d’affichage OLED, elle va prendre possession de le marché de l’écran mince dans quelques années et il y aura plus de nouvelles applications de cette technologie. Il y aura moins la limitation de l’écran dans la forme, l’aspect et le poids.

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