Pixel AMLCD

The issue of power consumption of an OLED display panel changing with the information content has not been well addressed in the OLED field. For AMLCD display panel, the power consumption is almost independent of the information content. For an AMOLED or an AMPLED panel, the power consumption is directly proportional to the number of pixels lighting up. For each display pixel, the power consumption is nearly proportional to the level of brightness (gray level). Thus, AMOLED display only consumes the power necessary, without any waste. This effect is similar to the concept of Pay-Per-View developed in cable and satellite TV industries. Two direct consequences of the Pay-Per-View effect are ... 

The hrst reported OTFT display was a 16 x 16 pixel electrophoretic display demonstrated by researchers at Bell Laboratories and E Ink Corporation in 2001 [19]. Fignre 6.4.9 shows operation of the 5 in. display, which used pentacene TFTs on a flexible film of polyethylene terephthalate (PET). Later in 2001 AMLCDs nsing... 

FIGURE 6.4.13 (a) Schematic and (b) cross-section of an OTFT AMLCD pixel (not to scale). 

For example, in a typical SXGA (1280 x 1024) AMLCD, the refresh rate is 60 Hz, the frame time is 16.7 msec, and the line time is 16.3 psec. For 6-bit resolution, the RC charging time constant must be less than 3.3 psec. The total pixel capacitance is about 0.5 pF, so the TFT on-resistance must be less than 6.6 Mil. From liquation... 

Like the standard AMLCD pixel, the two TFT AMOLED pixel is voltage programmed. That is, voltages are used to represent the image data. In 1998 Samoff Corporation, Planar America, Kodak, and Princeton University reported the earliest... 

Figure 88. The first version of Displaytech s miniature display (ChronoColor), which went into production in early 1997, in comparison with a conventional active matrix display. This microdisplay utilizes sequential color to produce full color on each pixel, resulting in a brighter, crisper image than that of an AMLCD, which uses a triad of red, green, and blue pixels to form a color. In the insets, the pixels of the ChronoColor display and AMLCD are magnified to show the difference in fill factors. The color is what makes the image that you see, and it occupies 75% of the display on the left, but only 35% of the corresponding active matrix display. (Courtesy of Displaytech, Inc.)...

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