AMOLED
As of 2012, AMOLED technology is used in mobile phones, media players and digital cameras,[1] and continues to make progress toward low-power, low-cost and large-size (for example, 40-inch) applications.[2][3][4]
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Design
Typically, this continuous current flow is controlled by at least two TFTs at each pixel (to trigger the luminescence), with one TFT to start and stop the charging of a storage capacitor and the second to provide a voltage source at the level needed to create a constant current to the pixel, thereby eliminating the need for the very high currents required for passive matrix OLED operation.[6]
TFT backplane technology is crucial in the fabrication of AMOLED displays. The two primary TFT backplane technologies, namely polycrystalline silicon (poly-Si) and amorphous silicon (a-Si), are used today in AMOLEDs. These technologies offer the potential for fabricating the active matrix backplanes at low temperatures (below 150°C) directly onto flexible plastic substrates for producing flexible AMOLED displays.[7]
Future development
Manufacturers have developed in-cell touch panels, integrating the production of capacitive sensor arrays in the AMOLED module fabrication process. In-cell sensor AMOLED fabricators include AU Optronics and Samsung. Samsung has marketed their version of this technology as Super AMOLED. Researchers at DuPont used computational fluid dynamics (CFD) software to optimize coating processes for a new solution-coated AMOLED display technology that is cost and performance competitive with existing chemical vapor deposition (CVD) technology. Using custom modeling and analytical approaches, they developed short- and long-range film-thickness control and uniformity that is commercially viable at large glass sizes.[8]Comparison to other technologies
AMOLED displays provide higher refresh rates than their passive-matrix OLED counterparts,[not specific enough to verify] improving response time often to under a millisecond, and they consume significantly less power.[9] This advantage makes active-matrix OLEDs well suited for portable electronics, where power consumption is critical to battery life.The amount of power the display consumes varies significantly depending on the colour and brightness shown. As an example, one commercial QVGA OLED display consumes 0.3 watts while showing white text on a black background, but more than 0.7 watts showing black text on a white background, while an LCD may consume only a constant 0.35 watts regardless of what is being shown on screen.[10] Because the black pixels actually turn off, AMOLED also has contrast ratios that are significantly better than LCD.
AMOLED displays may be difficult to view in direct sunlight compared with LCDs because of their reduced maximum brightness.[11] Samsung's Super AMOLED technology addresses this issue by reducing the size of gaps between layers of the screen.[12][13] Additionally, PenTile technology is often used to allow for a higher resolution display while requiring fewer subpixels than would otherwise be needed, often resulting in a display less sharp and more grainy compared with a non-pentile display with the same resolution.
The organic materials used in AMOLED displays are prone to degradation over a period of time, resulting in color shifts as one color fades faster than another, image persistence or burn-in. However, technology has been developed to compensate for material degradation.[14][15]
Current demand for AMOLED screens is high, and, due to supply shortages of the Samsung-produced displays, certain models of HTC smartphones have been changed to use next-generation LCD displays from the Samsung and Sony joint-venture SLCD in the future.[16][2] Construction of new production facilities in 2011 will increase the production of AMOLED screens to cope with demand.[17]
Super AMOLED displays, such as the one on the Samsung Galaxy S III have often been compared to IPS panel premium LCDs, found in the iPhone 4S and HTC One X. [3] [4]
Marketing terms
Super AMOLED
Super AMOLED is Samsung's term for an AMOLED display with an integrated digitizer, meaning, the layer that detects touch is integrated into the screen, rather than being overlaid on top of it. According to Samsung, Super AMOLED reflects 5 times less sunlight compared to the first generation AMOLED.[18][19] The display technology itself is not changed. Super AMOLED is part of the Pentile Matrix Family.For the Samsung Galaxy S III, which reverted to Super AMOLED instead of the pixelation-free conventional RGB (non-PenTile) Super AMOLED Plus of its predecessor Samsung Galaxy S II, the S III's larger screen size encourages users to hold the phone further from their face to obscure the PenTile effect.[5]
Super AMOLED Advanced
Super AMOLED Advanced is a term marketed by Motorola to describe a brighter display than Super AMOLED screens, but also a higher resolution – qHD or 960 × 540 for Super AMOLED Advanced compared to WVGA or 800 × 480 for Super AMOLED. This display equips the Motorola Droid RAZR.[20]Super AMOLED Plus
HD Super AMOLED
Future
Future displays exhibited in 2012 have shown even higher resolutions with phone displays (4 to 5 inches) having Full HD (1920 × 1200 or 1920 × 1080) resolution capabilities.sumber : http://en.wikipedia.org/wiki/AMOLED
