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Active Matrix OLED (AMOLED): introduction and basics
OLED displays are made from organic (carbon based) materials that emit light when electricity is applied. OLEDs can be used to create displays - and these are bright and efficient with a fast response time and a wide viewing angle. OLED display can be made very thin (the thinnest prototype is 50 microns...) and even transparent or flexible. The possibilities are almost endless... Here's more information on the technology behind AMOLEDs.
AMOLED: Active Matrix OLED
The term AMOLED means Active-Matrix OLED. The 'active-matrix' part refers to the driving electronics, or the TFT layer. When you display an image, you actually display it line by line (sequentially) as you can only change one line at a time. An AMOLED uses a TFT which contains a storage capacitor which maintains the line pixel states, and so enables large size (and large resolution) displays.
AMOLED vs PMOLED
A PMOLED uses a simpler kind of driver electronics - without a storage capacitor. This means that each line is turned off when you move to the next line. So let's say you have 10 rows in your display - each row will only be on 1/10 of the time. The brightness of each row has to be 10 times the brightness you'd get in an AMOLED. So you use more voltage which shortens the lifetime of the OLED materials and also results in a less efficient display. So while PMOLEDs are cheaper to make than AMOLEDs they are limited in size and resolution (the largest PMOLED is only 5", and most of them are around 1" to 3"). Most PMOLEDs are used for character display, and not to show photos or videos.
Samsung is the clear leader in AMOLED production. Samsung are actually using the term AMOLED to brand these kinds of displays. Samsung is making 2" to 5" panels today, used in many mobile phones, digital cameras and other mobile devices. Samsung is also showing prototypes of larger (14" up to 42") AMOLED panels, but these aren't produced yet.
Samsung's Super-AMOLED displays are AMOLED displays with an integrated touch function. Samsung has placed a touch-sensor (on-cell) over the display and made it evaporate. The thickness of the touch sensor is just 0.001mm and this allows the screen to provide better images and to have great visibility even in direct sunlight. Super-AMOLEDs also have better lifetime than regular AMOLED and are very responsive to touch. In January 2011 Samsung announced the 2nd-generation Super AMOLED Plus displays which offer more sub-pixels (they no longer use the PenTile matrix) and are also thinner, brighter and more efficient (by 18%) than the old Super AMOLED displays.
All OLED TV panels will actually be AMOLED TVs... Sony has been the first to make such a TV, the XEL-1 (back in 2007). Since then they have stopped production and marketing in Japan. The AMOLED TV was more of a technology demo than anything else. Even though it costs around $2500 for a 11" display, they were losing money on each set.
LG are the second company to introduce an AMOLED TV, the EL9500 which is a 15" TV that is also very expensive at $2500, and currently sold only in Korea and Europe