PATENT DOCUMENT

Publication Number: US-9047826-B2
Application Number: US-201213420298-A
Country: US
Kind Code: B2

Title: Systems and methods for liquid crystal display column inversion using reordered image data

Abstract:
Systems, methods, and devices for performing column inversion using reordered image data are provided. In one example, an electronic display may include a display panel with columns of pixels and driver circuitry to drive the pixels using column inversion. The driver circuitry may drive pixels of a first superpixel in a first color order and drive pixels of an adjacent second superpixel in a second color order, such that more pixels are driven sequentially at a common polarity than would have been driven sequentially at the common polarity were the pixels of the first superpixel driven at the same color order as the pixels of the second superpixel.

Claims:
What is claimed is: 
     
       1. An electronic display comprising:
 a display panel comprising columns of pixels; and 
 driver circuitry configured to drive the pixels using 2/1-column inversion or 4/2-column inversion, wherein the driver circuitry is configured to drive pixels of a first superpixel in a first color order and drive pixels of an adjacent second superpixel in a second color order, such that more pixels are driven sequentially at a common polarity than would have been driven sequentially at the common polarity were the pixels of the first superpixel driven at the same color order as the pixels of the second superpixel; 
 wherein the driver circuitry is configured to drive the pixels of the first superpixel in red-green-blue order and drive the pixels of the second superpixel in blue-green-red order; or 
 wherein the driver circuitry is configured to drive the pixels of the first superpixel in green-red-blue order and drive the pixels of the second superpixel in blue-red-green order; or 
 wherein the driver circuitry is configured to drive the pixels of the first superpixel in red-blue-green order and drive the pixels of the second superpixel in green-blue-red order. 
 
     
     
       2. The electronic display of  claim 1 , wherein the driver circuitry comprises a first demultiplexer configured to time demultiplex pixel data of the first superpixel and a second demultiplexer configured to time demultiplex pixel data of the second superpixel, wherein the first demultiplexer is configured to time demultiplex data in a different order than the second demultiplexer. 
     
     
       3. The electronic display of  claim 1 , wherein the driver circuitry is configured to drive the pixels using 2/1-column inversion, wherein transmittances of red and blue pixels are enhanced in relation to transmittances of green pixels. 
     
     
       4. The electronic display of  claim 1 , wherein the driver circuitry is configured to drive the pixels using 2/1-column inversion, wherein transmittances of red and green pixels are enhanced in relation to transmittances of blue pixels. 
     
     
       5. The electronic display of  claim 1 , wherein the driver circuitry is configured to drive the pixels using 2/1-column inversion, wherein transmittances of green and blue pixels are enhanced in relation to transmittances of red pixels. 
     
     
       6. The electronic display of  claim 1 , wherein the driver circuitry is configured to drive the pixels of the first superpixel and the second superpixel such that sequential polarity switches is reduced by half compared to a number of polarity switches that would have occurred were the pixels of the first superpixel driven at the same color order as the pixels of the second superpixel. 
     
     
       7. An electronic display comprising:
 a display comprising columns of pixels; and 
 driver circuitry configured to drive the pixels using 2/1-column inversion or 4/2-column inversion, wherein the driver circuitry is configured to drive pixels of a first superpixel in a first color order and drive pixels of an adjacent second superpixel in a second color order, such that more pixels are driven sequentially at a common polarity than would have been driven sequentially at the common polarity were the pixels of the first superpixel driven at the same color order as the pixels of the second superpixel; 
 wherein the driver circuitry comprises a first demultiplexer configured to time demultiplex pixel data of the first superpixel and a second demultiplexer configured to time demultiplex pixel data of the second superpixel, wherein the first demultiplexer is configured to time demultiplex pixel data in different order than the second demultiplexer; and 
 wherein the first demultiplexer is configured to time demultiplex pixel data associated with first, second, and third subpixels of the first superpixel in order of first to last and the second demultiplexer is configured to time demultiplex pixel data associated with first, second, and third subpixels of the second superpixel in order of last to first. 
 
     
     
       8. A method comprising:
 generating image data associated with first and second superpixels in one or more processors, wherein the image data associated with the first superpixel and the image data associated with the second superpixel have the same color order; 
 reordering the image data in the one or more processors or in an electronic display, or both, such that the image data associated with the first superpixel and the image data associated with the second superpixel have different color orders; and 
 driving the electronic display with the reordered image data using driving circuitry of the display such that more pixels are driven sequentially at a common polarity using the reordered image data than would have been driven sequentially at the common polarity had the display been driven with image data in the original order and such that:
 in one row of pixels, all pixels of a first polarity are adjacent to one other pixel of the first polarity and the one other pixel of a second polarity that is opposite the first polarity, and all pixels of the second polarity are adjacent on both sides to pixels of the first polarity; or 
 in one row of pixels, all pixels of a first polarity are adjacent to one other pixel of the first polarity and the one other pixel of a second polarity, and half all pixels of the second polarity are adjacent to one other pixel of the second polarity and one other pixels of the first polarity and the other half of all pixels of the second polarity are adjacent on both sides to pixels of the second polarity; or 
 a combination thereof; 
 
 wherein the image data associated with the second superpixel is reordered from red-green-blue order to blue-green-red order; or 
 wherein the image data associated with the first superpixel is reordered from red-green-blue order to green-red-blue order and the image data associated with the second superpixel is reordered from red-green-blue order to blue-red-green order; or 
 wherein the image data associated with the first superpixel is reordered from red-green-blue order to red-blue-green order and the image data associated with the second superpixel is reordered from red-green-blue order to green-blue-red order. 
 
     
     
       9. A system comprising:
 one or more processors to generate image data; and 
 an electronic display configured to display the image data, wherein the electronic display comprises:
 a display panel comprising columns of pixels; and 
 driving circuitry configured to drive the pixels using 2/1-column inversion or 4/2-column inversion, wherein the driver circuitry is configured to drive pixels of a first superpixel in a first color order and drive pixels of an adjacent second superpixel in a second color order, such that more pixels are driven sequentially at a common polarity than would have been driven sequentially at the common polarity were the pixels of the first superpixel driven at the same color order as the pixels of the second superpixel; 
 wherein the columns of pixels of the display panel are arranged in a repeating pattern of red-green-blue-blue-green-red; or 
 wherein the columns of pixels of the display panel are arranged in a repeating pattern of green-red-blue-blue-red-green; or 
 wherein the columns of pixels of the display panel are arranged in a repeating pattern of red-blue-green-green-blue-red order. 
 
 
     
     
       10. The system of  claim 9 , wherein the system comprises a desktop computer, a notebook computer, a handheld device, a tablet computer, or a combination thereof. 
     
     
       11. An article of manufacture comprising:
 one or more tangible, machine-readable media at least collectively comprising instructions to: 
 reorder image data associated with two superpixels of a from a first order, in which a subset of the image data associated with the first superpixel and a subset of the image data associated with the second superpixel both have the same color order, to a second order, in which the subset of the image data associated with the first superpixel and the subset of the image data associated with the second superpixel have different color orders; and 
 provide the reordered image data to driving circuitry to drive the display such that more pixels of the first and second superpixel are driven sequentially at a common polarity using the reordered image data than would have been driven sequentially at the common polarity had the display been driven with image data in the original order and such that:
 in one row of pixels, all pixels of a first polarity are adjacent to one other pixel of the first polarity and the one other pixel of a second polarity that is opposite the first polarity, and all pixels of the second polarity are adjacent on both sides to pixels of the first polarity; or 
 in one row of pixels, all pixels of a first polarity are adjacent to one other pixel of the first polarity and the one other pixel of a second polarity, and half all pixels of the second polarity are adjacent to one other pixel of the second polarity and one other pixels of the first polarity and the other half of all pixels of the second polarity are adjacent on both sides to pixels of the second polarity; or 
 a combination thereof; 
 
 wherein the image data associated with the second superpixel is reordered from red-green-blue order to blue-green-red order; or 
 wherein the image data associated with the first superpixel is reordered from red-green-blue order to green-red-blue order and the image data associated with the second superpixel is reordered from red-green-blue order to blue-red-green order; or 
 wherein the image data associated with the first superpixel is reordered from red-green-blue order to red-blue-green order and the image data associated with the second superpixel is reordered from red-green-blue order to green-blue-red order.

Description:
BACKGROUND 
     The present disclosure relates generally to liquid crystal displays (LCDs) and, more particularly, to LCDs that employ column inversion. 
     This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present techniques, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. 
     Electronic displays appear in many different electronic devices. One type of electronic display, a liquid crystal display (LCD), displays images by varying the amount of light passing through colored pixels (typically red, green, and blue pixels) using a layer of liquid crystal material. Pixels may be driven with particular voltages, causing the liquid crystal material to change orientation, thereby varying the amount of light passing through the pixel. The liquid crystal layer could become biased, however, if the voltages applied to a pixel are consistently of a single polarity (i.e., + or −). Biasing could disadvantageously alter the light transmission characteristics of an LCD. 
     Periodically inverting the driving voltages may prevent liquid crystal biasing. Whole-frame inversion, however, could introduce other artifacts. Accordingly, inversion schemes such as “dot inversion” or “column inversion” have been developed that may prevent biasing while avoiding artifacts caused by whole-frame inversion. Dot inversion typically involves driving all adjacent pixels of an LCD at opposite polarities and inverting these polarities on a frame-by-frame basis. Although dot inversion may prevent liquid crystal biasing, dot inversion may significantly increase the complexity of the driving circuitry. Column inversion is less complex and generally prevents biasing in a similar way as dot inversion. Unlike dot inversion, column inversion typically involves driving whole columns of pixels at the same polarity and inverting these polarities occasionally (e.g., on a frame-by-frame basis). Both dot inversion and column inversion generally may reduce the appearance of visual artifacts on the LCD caused by biasing. Performing these techniques, however, may consume a substantial amount of power. Moreover, LCD inversion schemes can produce crosstalk between neighboring pixels, reducing light transmittance in those pixels. 
     Aside from liquid crystal biasing, other potential problems may affect LCDs. Color reproduction, for instance, may vary from LCD to LCD. Such differences in color reproduction may arise from color variations in backlight elements (e.g., light emitting diodes (LEDs)), the light-diffusing components of backlight assemblies, and/or differences individual display panels. Ideally, the white point—the color emitted by the LCD when the LCD is programmed to display the color white—should be the same for all LCDs used in a type of electronic device. Under some circumstances, the white point may be adjusted through software processing before image data is sent to the LCD. Although effective, adjusting the white point in software may cause a loss of image data information. 
     SUMMARY 
     A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. 
     Embodiments of the present disclosure relate to systems, methods, and devices for performing column inversion using reordered image data. In one example, an electronic display may include a display panel with columns of pixels and driver circuitry to drive the pixels using column inversion. The driver circuitry may drive pixels of a first superpixel in a first color order and drive pixels of an adjacent second superpixel in a second color order, such that more pixels are driven sequentially at a common polarity than would have been driven sequentially at the common polarity were the pixels of the first superpixel driven at the same color order as the pixels of the second superpixel. By avoiding polarity switches over time, the driver circuitry may consume less power than otherwise. 
     Various refinements of the features noted above may exist in relation to various aspects of the present disclosure. Further features may also be incorporated in these various aspects as well. These refinements and additional features may exist individually or in any combination. For instance, various features discussed below in relation to one or more of the illustrated embodiments may be incorporated into any of the above-described aspects of the present disclosure alone or in any combination. The brief summary presented above is intended only to familiarize the reader with certain aspects and contexts of embodiments of the present disclosure without limitation to the claimed subject matter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which: 
         FIG. 1  is a schematic block diagram of an electronic device with a display having column inversion circuitry, in accordance with an embodiment; 
         FIG. 2  is an example of the electronic device of  FIG. 1  in the form of a notebook computer, in accordance with an embodiment; 
         FIG. 3  is an example of the electronic device of  FIG. 1  in the form of a handheld device, in accordance with an embodiment; 
         FIG. 4  is an example of the electronic device of  FIG. 1  in the form of a desktop computer, in accordance with an embodiment; 
         FIG. 5  is an exploded view of the display of the electronic device of  FIG. 1 , in accordance with an embodiment; 
         FIG. 6  is a block diagram of a backlight assembly of the display, in accordance with an embodiment; 
         FIG. 7  is a block circuit diagram illustrating driving circuitry of the display, in accordance with an embodiment; 
         FIG. 8  is a schematic diagram of a 3-column inversion scheme with enhanced blue pixel transmittance, in accordance with an embodiment; 
         FIGS. 9 and 10  are cross-sectional views of a liquid crystal layer between two pixels driven at opposite polarities at two respective spacings, D 1  and D 2 , in accordance with an embodiment; 
         FIG. 11  is a schematic diagram of a display panel employing 3-column inversion and having increased spacing between columns driven at opposite polarities, in accordance with an embodiment; 
         FIG. 12  is a schematic diagram of a display panel employing 2-column inversion and having increased spacing between columns driven at opposite polarities, in accordance with an embodiment; 
         FIG. 13  is a schematic diagram of a display panel employing 2-column Z-inversion and having increased spacing between columns driven at opposite polarities, in accordance with an embodiment; 
         FIGS. 14 and 15  are schematic diagrams of display panels employing 2/1-column inversion and having increased spacing between columns driven at opposite polarities, in accordance with an embodiment; 
         FIG. 16  is a flowchart describing a method for driving a display panel with improved transmittance between columns driven at opposite polarities, in accordance with an embodiment; 
         FIG. 17  is a schematic diagram of driving circuitry to perform 3-column inversion, in accordance with an embodiment; 
         FIG. 18  is a schematic diagram of a display panel employing 3-column inversion with increased blue pixel transmittance, in accordance with an embodiment; 
         FIG. 19  is a schematic diagram of driving circuitry to perform the 3-column inversion of  FIG. 18  using source amplifiers switched on a frame-by-frame basis, in accordance with an embodiment; 
         FIG. 20  is a schematic diagram of a display panel employing 3-column inversion with increased green pixel transmittance, in accordance with an embodiment; 
         FIG. 21  is a schematic diagram of a display panel employing 3-column inversion with increased red pixel transmittance, in accordance with an embodiment; 
         FIG. 22  is a schematic diagram of driving circuitry to perform the 3-column inversion of  FIG. 8  using source amplifiers switched on a frame-by-frame basis, in accordance with an embodiment; 
         FIG. 23  is a schematic diagram of another display panel employing 3-column inversion with increased red pixel transmittance, in accordance with an embodiment; 
         FIG. 24  is a schematic diagram of driving circuitry to perform the 3-column inversion of  FIG. 23  using source amplifiers switched on a frame-by-frame basis, in accordance with an embodiment; 
         FIG. 25  is a flowchart describing a method for driving a display panel using reordered image data, in accordance with an embodiment; 
         FIG. 26  is a schematic diagram of a display panel employing 2/1-column inversion that emphasizes blue and green pixel transmittance, in accordance with an embodiment; 
         FIG. 27  is a schematic diagram of a display panel employing 2/1-column inversion that emphasizes red and blue pixel transmittance, in accordance with an embodiment; 
         FIG. 28  is a schematic diagram of a display panel employing 2/1-column inversion that emphasizes red and green pixel transmittance, in accordance with an embodiment; 
         FIG. 29  is a schematic diagram of the driving circuitry of  FIG. 17  performing the 2/1-column inversion of  FIG. 26 , in accordance with an embodiment; 
         FIG. 30  is a timing diagram illustrating the electrical impact of performing the 2/1-column inversion of  FIG. 29 , in accordance with an embodiment; 
         FIG. 31  is a timing diagram illustrating the electrical impact of performing 2/1-column inversion when image data is reordered to reduce polarity switches, in accordance with an embodiment; 
         FIG. 32  is a schematic diagram of driving circuitry to perform the 2/1-column inversion of  FIG. 26  using the reordered image data of  FIG. 31 , in accordance with an embodiment; 
         FIG. 33  is a schematic diagram of a display panel employing 4/2-column inversion with increased blue pixel transmittance, in accordance with an embodiment; 
         FIG. 34  is a schematic diagram of driving circuitry to perform the 4/2-column inversion of  FIG. 33 , in accordance with an embodiment; 
         FIG. 35  is a timing diagram illustrating the electrical impact of reordering image data to carry out the 2/1 column inversion of  FIG. 27 , in accordance with an embodiment; 
         FIG. 36  is schematic diagram of another display panel employing 4/2-column inversion with increased blue pixel transmittance, in accordance with an embodiment; 
         FIG. 37  is a timing diagram illustrating the electrical impact of reordering image data to carry out the 2/1 column inversion of  FIG. 28 , in accordance with an embodiment; 
         FIG. 38  is schematic diagram of a display panel employing 4/2-column inversion with increased red pixel transmittance, in accordance with an embodiment; 
         FIG. 39  is a schematic diagram of driving circuitry to perform 2/1-column inversion of  FIG. 26  using three source amplifiers switched on a frame-by-frame basis, in accordance with an embodiment; 
         FIG. 40  is a schematic diagram of driving circuitry to perform 2/1-column inversion using three demultiplexers coupled to three of four source amplifiers switched on a frame-by-frame basis, in accordance with an embodiment; 
         FIG. 41  is a schematic diagram of driving circuitry to perform any suitable symmetrical column inversion scheme, including 3-column inversion, in accordance with an embodiment; 
         FIG. 42  is a schematic diagram of a display panel employing 1-column inversion, in accordance with an embodiment; 
         FIG. 43  is a schematic diagram illustrating the use of the driving circuitry of  FIG. 41  to perform the 1-column inversion of  FIG. 42 , in accordance with an embodiment; 
         FIG. 44  is a plot modeling possible white point adjustments to a display that may be obtained using column inversion, in accordance with an embodiment; 
         FIG. 45  is a flowchart describing a method for adjusting the white point of a display using 1-column and/or 3-column inversion, in accordance with an embodiment; 
         FIG. 46  is a flowchart describing an embodiment of a method for adjusting the white point of a display using 2/1-column inversion, in accordance with an embodiment; 
         FIG. 47  is a plot modeling display panel white points in relation to backlight white points, in accordance with an embodiment; 
         FIG. 48  is a flowchart describing a method for manufacturing a display with a display panel that compensates for backlight color, in accordance with an embodiment; 
         FIG. 49  is a flowchart describing a method for controlling a white point of a display by selecting a duty ratio of column inversion schemes, in accordance with an embodiment; 
         FIG. 50  is a chart illustrating column polarities over a series of frames of image data, in accordance with an embodiment; 
         FIG. 51  is a timing diagram showing a duty ratio of different column inversion schemes to adjust the white point of the display, in accordance with an embodiment; 
         FIG. 52  is a color space diagram modeling the white point adjustment occurring when the duty ratio of  FIG. 50  is applied, in accordance with an embodiment; 
         FIG. 53  is another chart illustrating column polarities over a series of frames of image data, in accordance with an embodiment; 
         FIG. 54  is another timing diagram showing a duty ratio of different column inversion schemes to adjust the white point of the display, in accordance with an embodiment; 
         FIG. 55  is a color space diagram modeling the white point adjustment occurring when the duty ratio of  FIG. 53  is applied, in accordance with an embodiment; 
         FIG. 56  is a flowchart of a method for adjusting the white point of a display using a duty ratio of 2/1-column inversion, in accordance with an embodiment; 
         FIG. 57  is a chart illustrating column polarities over a series of frames of image data when various 2/1-column inversion schemes are applied over time, in accordance with an embodiment; 
         FIG. 58  is a timing diagram showing a duty ratio of different 2/1-column inversion schemes to adjust the white point of the display, in accordance with an embodiment; and 
         FIG. 59  is a color space diagram modeling the white point adjustment occurring when the duty ratio of  FIG. 57  is applied, in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     One or more specific embodiments of the present disclosure will be described below. These described embodiments are only examples of the presently disclosed techniques. Additionally, in an effort to provide a concise description of these embodiments, all features of an actual implementation may not be described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but may nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. 
     As mentioned above, a liquid crystal display (LCD) modulates the amount of light passing through each pixel using an electric field through a liquid crystal layer. If voltage of a single polarity is consistently applied to the liquid crystal layer, a biasing of the liquid crystal layer may occur. This biasing could disadvantageously alter the light transmission characteristics of the LCD. Display driving techniques referred to as “column inversion” may prevent liquid crystal biasing. Some column inversion schemes are described in U.S. application Ser. No. 12/941,751, “COLUMN INVERSION SCHEMES FOR IMPROVED TRANSMITTANCE,” which is assigned to Apple Inc. and incorporated by reference herein in its entirely. 
     In general, column inversion involves driving some columns of pixels at one polarity and other columns of pixels at an opposite polarity. The polarities then are occasionally swapped (e.g., on a frame-by-frame basis). To provide a few examples, column inversion may involve driving adjacent groups of one, two, three, or more columns of pixels of the LCD at one polarity and driving other adjacent groups of one, two, three or more columns of pixels at an opposite polarity. Occasionally, such as when every new frame of image data is programmed onto the display, the polarities may be swapped. In a 1-column inversion scheme, each adjacent column of pixels is driven at a polarity opposite the other. In a 2-column inversion scheme, groups of two adjacent columns are driven at the same polarity, alternating every group of two columns. Similarly, in a 3-column inversion scheme, groups of three columns of pixels are driven at the same polarity, alternating every group of three columns. 
     Driving adjacent pixels at opposite polarities reduces their transmittance. Since 1-column inversion involves polarity switches between every adjacent column of pixels, the transmittance of every pixel may be equally reduced. Performing 2-column inversion instead of 1-column inversion may avoid half of these polarity switches. Thus, 2-column inversion may offer greater pixel transmittance over 1-column inversion. In 3-column inversion, groups of three adjacent columns are driven at the same polarity. The center column of such a group of three will be surrounded on both sides by pixels driven at the same polarity. The outer columns of the group of three will each be adjacent to a column of pixels driven at an opposite polarity. As such, the transmittance of the pixels of the center column of the group of three will be enhanced in relation to those of the outer columns of the group of three. 
     The present disclosure describes several ways column inversion may mitigate or use to advantage the differences in pixel transmittance caused by different column inversion schemes. In one example, columns of pixels that will be driven at opposite polarities may be spaced farther apart than columns of pixels that will be driven at the same polarity. The additional space between those pixels driven at opposite polarities may reduce the effect of the polarity switch on the liquid crystal material. As a result, the transmittances of pixels adjacent to those of opposite polarity may be reduced to a lesser degree. Depending on the spacing, the reduction in transmittance may be reduced significantly or even substantially eliminated. 
     In another example, selecting or varying the column inversion scheme may permit the white point of the LCD to be adjusted. Specifically, the variations in pixel transmittance caused by polarity switches may affect the relative transmittance of pixels of different colors. For instance, selecting a 3-column inversion scheme in which columns of blue pixels are central may cause blue pixels to have enhanced transmittance in relation to green and red pixels. As a result, the white point of the display may shift toward blue. Additionally or alternatively, various column inversion schemes may be varied over time. Selecting a duty ratio of different column inversion schemes may cause the white point of the display to shift in any one of several possible color directions. 
     Additionally or alternatively, certain driving circuitry and/or driving techniques may enable reduced power consumption for some column inversion schemes. For example, temporal polarity switches occurring in some driving circuitry could cause the driving circuitry to consumer more power. That is, in general, the more polarity switches occurring over time, the more power consumed by the driving circuitry. In some examples, temporal polarity switches may be avoided by changing the order that image data enters the driving circuitry. Additionally or alternatively, demultiplexers used to funnel data to particular unit source drivers may be configured such that a single source amplifier provides data to a single demultiplexer each frame. By reducing electrically costly polarity switches in the driving circuitry, power may be conserved while a column inversion scheme is applied. 
     With the foregoing in mind, a variety of electronic devices may incorporate the electronic displays and driving circuitry discussed above. One example appears in a block diagram of  FIG. 1 , which describes an electronic device  10  that may include, among other things, one or more processor(s)  12 , memory  14 , nonvolatile storage  16 , a display  18  having outer resistive trace(s)  20 , input structures  22 , an input/output (I/O) interface  24 , network interfaces  26 , and/or temperature-sensing circuitry  28 . The various functional blocks shown in  FIG. 1  may include hardware, executable instructions, or a combination of both. In the present disclosure, the processor(s)  12  and/or other data processing circuitry may be generally referred to as “data processing circuitry.” This data processing circuitry may be embodied wholly or in part as software, firmware, hardware, or any combination thereof. Furthermore, the data processing circuitry may be a single, contained processing module or may be incorporated wholly or partially within any of the other elements within the electronic device  10 .  FIG. 1  is merely one example of a particular implementation and is intended to illustrate the types of components that may be present in electronic device  10 . These components may be found in various examples of the electronic device  10 . By way of example, the electronic device  10  of  FIG. 1  may represent a block diagram of a computer as depicted in  FIG. 2 , a handheld as device depicted in  FIG. 3 , or similar devices. 
     As shown in  FIG. 1 , the processor(s)  12  and/or other data processing circuitry may be operably coupled with the memory  14  and the nonvolatile storage  16 . In this way, the processor(s)  12  may execute instructions to carry out various functions of the electronic device  10 . Among other things, these functions may include generating image data in a particular order to be displayed on the display  18 , though it may be appreciated that the display  18  may additionally or alternatively perform such functions. The programs or instructions executed by the processor(s)  12  may be stored in any suitable article of manufacture that includes one or more tangible, computer-readable media at least collectively storing the instructions or routines, such as the memory  14  and/or the nonvolatile storage  16 . The memory  14  and the nonvolatile storage  16  may represent, for example, random-access memory, read-only memory, rewritable flash memory, hard drives, and optical discs. 
     The display  18  may be any suitable liquid crystal display (LCD) having suitable column inversion circuitry  20 . In some embodiments, the display  18  may also serve as a touch-screen input device. For example, the display  18  may be a MultiTouch™ touch screen device that can detect multiple touches at once. The column inversion circuitry  20  may perform column inversion according to any of the techniques discussed herein. For example, the column inversion circuitry  20  may represent a particular configuration of demultiplexers used in driving circuitry to minimize the power consumption of source amplifiers used in the display  18 . Additionally or alternatively, the column inversion circuitry  20  may represent circuitry to effect a particular configuration or duty ratio of column inversion to adjust the white point of the display  18 . The column inversion circuitry  20  may also represent circuitry to temporally adjust the manner in which image data is processed through the driving circuitry to reduce the number of polarity switches per frame, thereby reducing power consumption. 
     The input structures  22  of the electronic device  10  may enable a user to interact with the electronic device  10  (e.g., pressing a button to increase or decrease a volume level). The I/O interface  24  may enable electronic device  10  to interface with various other electronic devices, as may the network interfaces  26 . The network interfaces  26  may include, for example, interfaces for a personal area network (PAN), such as a Bluetooth network, for a local area network (LAN), such as an 802.11x Wi-Fi network, and/or for a wide area network (WAN), such as a 3G or 4G cellular network. The temperature-sensing circuitry  28  may detect a temperature of the display  18 . Since the temperature of the display  18  could affect the white point of the display  18 , the electronic device  10  may select a column inversion scheme that the display  18  may use. The column inversion scheme used by the display  18  may cause the white point of the display to shift in a desired color direction. 
     The electronic device  10  may take the form of a computer or other type of electronic device. For example, the electronic device  10  in the form of a computer may be a model of a MacBook®, MacBook® Pro, MacBook Air®, iMac®, Mac® mini, or Mac Pro® available from Apple Inc.  FIG. 2  provides one example of the electronic device  10  in the form of a notebook computer  30 . The computer  30  may include a housing  32 , a display  18 , input structures  22 , and ports of an I/O interface  24 . The input structures  22 , such as a keyboard and/or touchpad, may be used to interact with the computer  30 . Via the input structures  22 , a user may start, control, or operate a GUI or applications running on computer  30 . 
     The computer  30  may include the display  18 . Thus, in certain examples, the computer  30  may consume relatively less power than other similar devices without the column inversion circuitry  20  discussed herein. Likewise, in certain examples, the computer  30  may display images having a consistent white point across many different devices in a product line. 
     The electronic device  10  may also take the form of a handheld device  34 , as generally illustrated in  FIG. 3 . The handheld device  34  may represent, for example, a portable phone, a media player, a personal data organizer, a handheld game platform, or any combination of such devices. By way of example, the handheld device  34  may be a model of an iPod® or iPhone® available from Apple Inc. of Cupertino, Calif. In other embodiments, the handheld device  34  may be a tablet-sized embodiment of the electronic device  10 , which may be, for example, a model of an iPod® available from Apple Inc. 
     The handheld device  34  may include an enclosure  36  to protect interior components from physical damage and to shield them from electromagnetic interference. The enclosure  36  may surround the display  18 , which may display indicator icons  38 . The indicator icons  38  may indicate, among other things, a cellular signal strength, Bluetooth connection, and/or battery life. The I/O interfaces  24  may open through the enclosure  36  and may include, for example, a proprietary I/O port from Apple Inc. to connect to external devices. User input structures  40 ,  42 ,  44 , and  46 , in combination with the display  18 , may allow a user to control the handheld device  34 . A microphone  48  may obtain a user&#39;s voice for various voice-related features, and a speaker  50  may enable audio playback and/or certain phone capabilities. A headphone input  52  may provide a connection to external speakers and/or headphones. Like the computer  30 , in certain examples, the handheld device  34  may consume relatively less power than other similar devices without the column inversion circuitry  20  discussed herein. Likewise, in certain examples, the handheld device  34  may display images having a consistent white point across many different devices in a product line. 
     The electronic device  10  also may take the form of a desktop computer  56 , as generally illustrated in  FIG. 4 . In certain embodiments, the electronic device  10  in the form of the desktop computer  56  may be a model of an iMac®, Mac® mini, or Mac Pro® available from Apple Inc. The desktop computer  56  may include a housing  58 , a display  18 , and input structures  22 , among other things. The input structures  22 , such as a wireless keyboard and/or mouse, may be used to interact with the desktop computer  56 . Via the input structures  22 , a user may start, control, or operate a GUI or applications running on the desktop computer  56 . 
     The display  18  may be a backlit liquid crystal display (LCD). Thus, in certain examples, the desktop computer  56  may consume relatively less power than other similar devices without the column inversion circuitry  20  discussed herein. Likewise, in certain examples, the desktop computer  56  may display images having a consistent white point across many different devices in a product line. 
     Regardless of whether the electronic device  10  takes the form of the computer  30  of  FIG. 2 , the handheld device  34  of  FIG. 3 , the desktop computer  56  of  FIG. 4 , or some other form, the display  18  of the electronic device  10  may form an array or matrix of picture elements (pixels). By varying an electric field associated with each pixel, the display  18  may control the orientation of liquid crystal disposed at each pixel. The orientation of the liquid crystal of each pixel may permit more or less light emitted from a backlight to pass through each pixel. The display  18  may employ any suitable technique to manipulate these electrical fields and/or the liquid crystals. For example, the display  18  may employ transverse electric field modes in which the liquid crystals are oriented by applying an in-plane electrical field to a layer of the liquid crystals. Examples of such techniques include in-plane switching (IPS) and/or fringe field switching (FFS) techniques. 
     By controlling of the orientation of the liquid crystals, the amount of light emitted by the pixels may change. Changing the amount of light emitted by the pixels will change the colors perceived by a user of the display  18 . Specifically, a group of pixels may include a red pixel, a green pixel, and a blue pixel, each having a color filter of that color. By varying the orientation of the liquid crystals of different colored pixels, a variety of different colors may be perceived by a user viewing the display. It may be noted that the individual colored pixels of a group of pixels may also be referred to as unit pixels. 
     With the foregoing in mind,  FIG. 5  depicts an exploded view of different layers of a pixel  60  of the display  18 . The pixel  60  includes an upper polarizing layer  64  and a lower polarizing layer  66  that polarize light  70  emitted by a backlight assembly  68 . A lower substrate  72  is disposed above the polarizing layer  66  and is generally formed from a light-transparent material, such as glass, quartz, and/or plastic. 
     A thin film transistor (TFT) layer  74  appears above the lower substrate  72 . For simplicity, the TFT layer  74  is depicted as a generalized structure in  FIG. 5 . In practice, the TFT layer may itself include various conductive, non-conductive, and semiconductive layers and structures that generally form the electrical devices and pathways that drive the operation of the pixel  60 . The TFT layer  74  may also include an alignment layer (formed from polyimide or other suitable materials) at the interface with a liquid crystal layer  78 . 
     The liquid crystal layer  78  includes liquid crystal particles or molecules suspended in a fluid or gel matrix. The liquid crystal particles may be oriented or aligned with respect to an electrical field generated by the TFT layer  74 . The orientation of the liquid crystal particles in the liquid crystal layer  78  determines the amount of light transmission through the pixel  60 . Thus, by modulation of the electrical field applied to the liquid crystal layer  78 , the amount of light transmitted though the pixel  60  may be correspondingly modulated. 
     Disposed on the other side of the liquid crystal layer  78  from the TFT layer  74  may be one or more alignment and/or overcoating layers  82  interfacing between the liquid crystal layer  78  and an overlying color filter  86 . The color filter  86  may be a red, green, or blue filter, for example. Thus, each pixel  60  corresponds to a primary color when light is transmitted from the backlight assembly  68  through the liquid crystal layer  78  and the color filter  86 . 
     The color filter  86  may be surrounded by a light-opaque mask or matrix, represented here as a black mask  88 . The black mask  88  circumscribes the light-transmissive portion of the pixel  60 , delineating the pixel edges. The black mask  88  may be sized and shaped to define a light-transmissive aperture over the liquid crystal layer  78  and around the color filter  86 . In addition, the black mask  88  may cover or mask portions of the pixel  60  that do not transmit light, such as the scanning line and data line driving circuitry, the TFT, and the periphery of the pixel  60 . In the example of  FIG. 5 , an upper substrate  92  may be disposed between the black mask  88  and color filter  86  and the polarizing layer  64 . The upper substrate  92  may be formed from light-transmissive glass, quartz, and/or plastic. 
     The backlight assembly  68  provides light  70  to illuminate the display  18 . As seen in  FIG. 6 , the backlight assembly  68  may include, among other things, one or more backlight elements  100  such as light emitting diode (LED) strings  102 . Although the backlight elements  100  in  FIG. 6  are shown to be LED strings  102 , additionally or alternatively, any other suitable light emitting backlight elements  100  may be employed. For example, one or more cold cathode lighting elements may be used in lieu of, or in addition to, the LED strings  102 . Moreover, although the LED strings  102  of the backlight assembly  68  schematically appear to be disposed in discrete locations apart from one another, the LED strings  102  may be interleaved among one another. 
     In  FIG. 6 , the backlight elements  100  are illustrated as located at the edge of a diffuser  104 , rather than directly underneath. The light  70  may enter the light diffuser  104 , which may cause the light  70  to be diffused substantially evenly. Additionally, the light diffuser  104  may cause the light to pass up through the other layers of the display  18 , which have been generally discussed above with reference to  FIG. 5 . Moreover, while the backlight assembly  68  of  FIG. 6  is represented as an edge-lit backlight assembly  68 , other arrangements are possible. Indeed, the backlight elements  100  may be disposed in any suitable arrangement, including being disposed beneath or behind the backlight diffuser  104 . 
     In any case, the white point of the display  18  may be affected by the color of the light  70  emitted by the backlight assembly  68 . In particular, different LEDs from backlight elements  100  of different backlight assemblies may emit different colors of light  70 . Moreover, different diffusers  104  of different backlight assemblies may cause the color of the light  70  to shift in different ways. As will be discussed further below, the impact of these variable colors on the white point of the display  18  may be mitigated by selecting a particular column inversion scheme or duty ratio of column inversion schemes. 
     The light  70  emitted through the backlight may pass through the pixels  60  of the display  18  in varying amounts depending on the way the pixels  60  are driven. In  FIG. 7 , a circuit diagram illustrates various components that may be present in the display  18  to modulate the light  70  through the various pixels  60 . For example, image data  106  and/or control signals  108  may be received by a timing controller  110 . Using the image data  106  and/or the control signals  108 , the timing control  110  may cause a source driver  112  and a gate driver  114  to program pixels  60  of a pixel array of a display panel  118 . The timing controller  110  may receive the image data  106  and/or control signals  108  from the processor(s)  12  and/or a display controller (e.g., an Embedded Display Port (eDP) enabled display controller). The timing controller  110  may include any suitable components (e.g., software, firmware, or hardware) for image data reordering  120 , white point selection  122 , and/or column inversion selection  124 . It should be appreciated that not all of these components may be present in every example of the present disclosure. Indeed, various embodiments may include more or fewer components. 
     Describing each of these possible components in particular, the image data reordering component  120  may change the order of the image data  106  to enable a power-efficient manner of performing certain column inversion schemes. Specifically, the image data  106  generally may be received from the processor(s)  12  as 8-bit or 6-bit image data in a red-green-blue format. Unless the image data  106  is reordered beforehand, the timing controller  110  to the source driver  112  in the red-green-blue order may supply the image data  106 . As will be discussed below, however, the image data reordering component  120  of the source driver  112  may, in some examples, drive pixels in a different order to improve the power consumption of the display  18 . 
     In some cases, as will be discussed below, the display  18  may have a white point selected or varied based on certain column inversion schemes. For example, the components of the display  18  may operate to cause the white point to shift toward red, green, and/or blue. In one example, the timing controller  110 , source driver  112 , and gate driver  114  may carry out a particular column inversion scheme that increases the transmittance of the red, green, and/or blue pixels of the display  18 . During the manufacture of the display  18 , for example, a particular display panel configuration may be installed into the display  18  that, when a column inversion scheme is carried out, shifts more toward red, green, or blue in a way so as to offset the color emitted by the backlight assembly  68 . In another example, the white point selection component  122  may cause the driving circuitry  110 ,  112 , and/or  114  to apply various column inversion schemes according to a duty ratio that varies the white point of the display  18  in a red, green, and/or blue direction. In this way, a relatively precise variation in the white point may be effected by the driving circuitry of the display  18 . In some embodiments, the column inversion selection component  124  and/or the white point selection component  122  may vary operation depending on a value of a temperature from the temperature-sensing circuitry  28 . Since the temperature of the display  18  may impact the white point of the display  18 , different temperatures may imply that certain column inversion schemes may be used to more closely achieve a desired white point. In another example, the white point selection component  122  may differentiate between a desired white point and a starting white point of the display  18  (e.g., as programmed upon the manufacture of the display  18 ). The white point selection component  122  may cause the column inversion selection component  124  to vary which column inversion scheme is applied so as to likely achieve a white point closer to the desired white point. 
     The column inversion selection component  124  may enable the selection of a particular column inversion scheme. In some examples, the white point selection component  122  and/or column inversion selection component  124  may represent a memory register that causes the timing controller  110  to control the source driver  112  and gate driver  114  to carry out certain column inversion schemes. The column inversion selection component  124  may relate to which type of column inversion scheme the driving circuitry  110 ,  112 , and/or  114  use to drive the display panel  118 . For example, the column inversion selection component  124  may control the switches used in the driving circuitry and/or the order of the image data supplied to the driving circuitry to apply a particular column inversion scheme. 
     Using timing and data signals from the timing controller  110 , the gate driver  114  may apply a gate activation signal across gate lines  126 , and the source driver  112  may apply image data signals (e.g., red (R), green (G), and blue (B) image data) on source lines  128  to program rows of pixels  60 . Each pixel includes a thin film transistor (TFT)  130 . A drain  132  of each TFT  130  is attached to a pixel electrode (PE)  134 . A source  136  of each TFT  130  supplies the respective data signals to the pixel electrode (PE)  134  when a gate  138  of the TFT  130  is activated. As such, when a gate signal is applied across a gate line  126 , the respective TFTs  130  whose gates  138  are coupled to that gate line  126 , will become activated. Data signals provided by the source driver  112 —by now converted into an analog voltage—to the source lines  128  will be programmed onto the particular pixel electrodes (PEs)  134 . The voltage difference between the signal programmed on the pixel electrode  134  and a corresponding common electrode (not shown) will generate an electric field. This electric field will vary the liquid crystal layer  78  to modulate the amount of light passing through the pixel  60 . By varying the amount of light passing through red, green, and blue pixels, a great variety of colors can be expressed on the display  18 . 
     To prevent the liquid crystal layer  78  of the display  18  from becoming biased, the data signals supplied to the pixel electrodes (PEs)  134  the polarity of the signals will be switched occasionally under a column inversion scheme. This may generally mean that the polarity of data supplied to a pixel  60  may be switched each frame, although the polarity of the data may be switched at other times (e.g., after multiple frames). In any case, a particular column inversion scheme may involve supplying all pixels of a particular column of pixels with data of the same polarity during at least one frame. 
     One example of a column inversion scheme that may be applied by the display  18  appears in a display panel layout  150  of  FIG. 8 . In particular, the display panel layout  150  of  FIG. 8  illustrates a 3-column inversion scheme on the pixel array of the display panel  118 . The example of  FIG. 8  shows a subset of the pixels  60  appearing on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Note that each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . 
     Each pixel  60  modulates light through a red, green, or blue filter. In the example of  FIG. 8 , groups of red (R), green (G), and blue (B) pixels form superpixels (e.g., superpixels  152 A and  152 B). The 3-column inversion scheme illustrated in the display panel layout  150  repeats every two superpixels  152 . Thus, the two superpixels  152 A and  152 B include the following polarities: R(−), G(+), B(+), R(+), G(−), and B(−). This pattern may repeat across the entire display  18 . The polarities of these columns are switched occasionally (e.g., on a frame-by-frame basis). Thus, at a different time, the two superpixels  152 A and  152 B may instead include the following polarities: R(+), G(−), B(−), R(−), G(+), and B(+). 
     The display panel layout  150  of  FIG. 8 , employing the 3-column inversion scheme so shown, may have the effect of emphasizing the transmittance of the blue pixels  60  of the pixel array of the display panel  118 . Specifically, columns of pixels  60  driven at opposite polarities adjacent to one another will have slightly lower transmittance than adjacent columns of pixels  60  driven at the same polarities. An explanation appears in  FIG. 9 . Specifically, a liquid crystal diagram  160  of  FIG. 9  represents a cross-sectional view of two subpixels driven at opposite polarities in the superpixel  152 A of  FIG. 8  at cut lines  9 - 9 . In the liquid crystal diagram  160 , the liquid crystal molecules of the liquid crystal layer  78  are shown to vary in orientation between two pixels  60 A and  60 B. In the example of  FIG. 9 , the pixel  60 A is a red pixel driven at a negative polarity and the pixel  60 B is a green pixel driven at a positive polarity. The pixel  60 A includes a pixel electrode  134 A and the pixel  60 B includes a pixel electrode  134 B. A distance D 1  separates the pixel electrodes  134 A and  134 B. In the example of  FIG. 9 , the distance D 1  represents a separation distance typical of two adjacent pixels. However, when driven at opposite polarities, the orientation of the liquid crystals molecules of the liquid crystal layer  78  may twist in such a way that transmittance is reduced. Specifically, as illustrated at areas  162  of the liquid crystal layer  78 , such liquid crystal twisting results in reduced transmittance of light passing through the liquid crystal areas  162 . 
     Increasing the spacing between the pixel electrodes  134 A and  134 B, as shown in  FIG. 10 , may mitigate this reduced transmittance. In  FIG. 10 , a liquid crystal diagram  170  shows that the orientation of the liquid crystal molecules of the liquid crystal layer  78  do not include the type of twisting found in the areas  162  of  FIG. 9  when the spacing is increased. Specifically, pixel electrodes  134 A and  134 B are disposed far enough apart from one another, at a distance D 2 , such that the transmittance of the pixels  60 A and  60 B are not significantly reduced. Indeed, the distance D 2  may be selected such that the transmittance through pixels  60 A and  60 B, driven at opposite polarities, may be substantially the same as similar pixels driven at the same polarity when supplied that same image data signals. 
       FIGS. 11-15  illustrate various display panel layouts in which columns of pixels are driven at opposite polarities are spaced further apart than columns driven at the same polarities. The examples of  FIGS. 11-15  all show a subset of the pixels  60  appearing on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . Each pixel  60  modulates light through a red, green, or blue filter. In the examples of  FIGS. 11-15 , red (R), green (G), and blue (B) pixels may have spacings between one another that vary depending on the column inversion scheme that the display panel  118  can carry out. In particular, adjacent columns of pixels driven at opposite polarities may be spaced farther apart (e.g., distances D 2 ) than adjacent columns of pixels driven at the same polarity (e.g., distances D 1 ). 
     In the examples of  FIGS. 11-15 , it should be appreciated that the distances D 1  and the distances D 2  need not be uniform everywhere throughout the display panel  118 . Indeed, the distances D 1  in one location of the display panel  118  may vary somewhat from the distances D 1  in another location of the display panel  118 . Likewise, the distances D 2  in one location of the display panel  118  may vary somewhat from the distances D 2  in another location of the display panel  118 . For example, local electrical conditions may vary slightly, increasing or decreasing the impact of the distances D 2  on the transmittance of adjacent pixels  60 . In any case, however, nearby distances D 2  may always be larger than nearby distances D 1 . As discussed above, the distance D 2  may be selected to be any suitable distance that reduces the loss of transmittance caused by the change in polarity between certain adjacent columns. The distance D 2  may be larger than D 1 , but it should be appreciated that the distances D 1  and D 2  may not have the precise relationship shown schematically in  FIGS. 11-15 . Moreover, it should be appreciated that while  FIGS. 11-15  provide a few specific examples of display panel layouts with columns of pixels separated by distances D 1  and D 2 , these examples are not meant to be exhaustive. Indeed, these examples are meant to suggest any suitable variations (e.g., which colors of pixels are grouped into columns, which pixel colors are selected as the center pixel(s) in groups of columns of pixels driven at like polarity, and so forth) while illustrating the application of variable spacings between certain columns of pixels. 
       FIG. 11  schematically illustrates a display panel layout  180  that employs 3-column inversion with certain variable spacing to reduce losses in pixel transmittance. The display panel layout  180  of  FIG. 11  is similar to the display panel layout  150  of  FIG. 8 , except that columns of pixels of opposite polarities are spaced farther apart. As seen in  FIG. 11 , adjacent green (G) and blue (B) pixels and adjacent red (R) and blue (B) pixels will be driven at the same polarities. As such, any suitable distance D 1  may separate these pixels from one another. On the other hand, adjacent red (R) and green (G) pixels will be driven at opposite polarities. As such, any suitable distance D 2  greater than D 1  may separate adjacent red (R) and green (G) pixels. 
       FIG. 12  schematically illustrates a display panel layout  190  that employs 2-column inversion with certain variable spacing to reduce losses in pixel transmittance. In  FIG. 12 , groups of two adjacent pixels are driven at the same polarity, which alternates accordingly throughout the display panel  118 . Thus, as shown in  FIG. 12 , first adjacent columns of red (R) and green (G) pixels both may be driven at one polarity, while the next two adjacent columns—blue (B) and red (R)—both may be driven an opposite polarity from that of the first two columns of red (R) and green (G) pixels. In keeping with the discussion above, a distance D 1  may separate the first adjacent columns of red (R) and green (G) pixels and a distance D 1  may separate the subsequent blue (B) and red (R) columns of pixels. To reduce the impact of driving the columns of green (G) and blue (B) pixels in the second and third columns shown in  FIG. 12  at opposite polarities, however, these columns of pixels may be separated by a suitable distance D 2  larger than the distance D 1  (e.g., D 2 ). 
     The configuration generally shown in  FIG. 12  may be adjusted to obtain a display panel layout  200  of  FIG. 13 , in which pixel electrodes  134  of columns are alternately disposed on different sides of the source lines  128  to create a zig-zag pattern of columns. Although the example of  FIG. 13  employs 2-column inversion, the zig-zag pattern shown in  FIG. 13  may alternatively employ any other suitable column inversion scheme (e.g., 3-column inversion) by grouping more columns of pixels together driven at the same polarity. In any case, the resulting column inversion may be referred to as Z-inversion due to the Z-shaped pattern appearing on the display panel  118 . In  FIG. 13 , as in  FIG. 12 , a distance D 1  may separate the first adjacent columns of red (R) and green (G) pixels and a distance D 1  may separate the subsequent blue (B) and red (R) columns of pixels despite the zig-zag pattern of the columns. To reduce the impact of driving the columns of green (G) and blue (B) pixels in the second and third columns shown in  FIG. 13  at opposite polarities, however, these columns of pixels may be separated by a suitable distance D 2  larger than the distance D 1 . 
     In  FIG. 14 , a display panel layout  202  implements a 2/1-column inversion scheme with variable separation distances between columns. While a frame is being programmed onto the pixels  60  of the display panel  118 , red (R) pixels are driven at one polarity and green (G) and blue (B) pixels are driven at another polarity. In other examples, green (G) or blue (B) may take the place of red (R) in the display panel layout  202  of  FIG. 14 . In any case, a distance D 1  may separate adjacent columns both driven at one polarity, while a distance D 2  may separate the solitary columns driven at the other polarity from the others. 
     A display panel layout  204  of  FIG. 15  represents an example of 4/2 column inversion, in which columns of pixels appear in the following order: red, green, blue, blue, green, red, and so forth. In a manner similar to the display panel layout  202  of  FIG. 14 , while a frame is being programmed onto the pixels  60  of the display panel  118 , red (R) pixels are driven at one polarity and green (G) and blue (B) pixels are driven at another polarity. As such, groups of two columns of pixels (adjacent red (R) pixels) of one polarity and groups of four columns (adjacent green (G), blue (B), blue (B), and green (G) pixels) of another polarity may be formed. A distance D 2  may separate these larger groups of pixels, while an internal distance D 1  may separate individual pixels in the groups. 
       FIG. 16  is a flowchart  206  describing a method for driving a display  18  using a display panel layout such as those discussed above with reference to  FIGS. 11-15 . The flowchart  206  may begin when the timing controller  110  receives image data  106  for a first frame (block  208 ). A first column of pixels  60  may be driven at a positive polarity (block  210 ). An adjacent column of pixels  60  also may be driven at the positive polarity when spaced the distance D 1  from the first column of pixels (block  212 ). When spaced the distance D 2  from the first column of pixels, the adjacent column of pixels may be driven at a negative polarity (block  212 ). At a later time, the timing controller  110  may receive image data  106  for a second frame (block  214 ). For this second frame, the first column of pixels  60  may be driven at a negative polarity (block  216 ). The adjacent column of pixels  60  may be driven at the negative polarity for the second frame when spaced the distance D 1  from the first column of pixels (block  212 ). When spaced the distance D 2  from the first column of pixels, the adjacent column of pixels may be driven at a positive polarity for the second frame (block  212 ). 
     Regardless of whether the spacings D 1  and D 2  appear in the display  18  as discussed above, 3-column inversion may provide an efficient manner of driving columns of pixels  60  of the display  18 . When the spacings D 1  and D 2  are not used, however, it should be noted that certain column inversion schemes may affect the transmittance of certain colors of the display panel  118 . In the 3-column inversion discussed above with reference to  FIG. 8 , for example, the transmittance of blue pixels  60  may be enhanced in relation to the other pixels. Specifically, since columns of blue pixels are driven at the same polarity as adjacent columns of green and red pixels, the loss of transmittance discussed above with reference to  FIG. 9  does not occur on either side of the column of blue pixels. On the other hand, the columns of pixels on opposite sides of the red and green pixels of a group of red, blue, and green pixels driven at the same polarity, may be driven at opposite polarities. Thus, the transmittance may be reduced in the red pixels and green pixels in relation to the blue pixels. Thus, when carrying out the 3-column inversion of  FIG. 8 , blue pixels may have greater transmittance than the red pixels or green pixels. 
     Columns of superpixels  152 A and  152 B may be driven according to a 3-column inversion scheme, such as that described above with reference to  FIG. 8 , using driving circuitry  220  shown in  FIG. 17 . The driving circuitry  220  may receive image data  106  in the same order it may be received from the processor(s)  12 . Specifically, first image data  222  may include image data  106  for the first superpixel  152 A in red, green, blue order (e.g., R 1 , G 1 , B 1 ). Second image data  224  for the second superpixel  152 B is also supplied in red, green, blue order (e.g., R 2 , G 2 , B 2 ). 
     In the example of  FIG. 17 , the ultimate polarities of the image data supplied to the driving circuitry  220  are shown to be R 1 (+), G 1 (−), B 1 (−), R 2 (−), G 2 (+), and B 2 (+). As such, in the example of  FIG. 17 , the driving circuitry  220  may include a demultiplexer  226  to feed the image data  106  into a positive source amplifier  228  or a negative source amplifier  230 . In alternative embodiments, the image data  106  may feed into both the positive source amplifier  228  and the negative source amplifier  230 . The resulting amplified analog image data may be output to a multiplexer  232  before being demultiplexed, using a demultiplexer  234 , and output to a 3-column time demultiplexer  236  or  238 . Additionally or alternatively, the multiplexer  232  and the demultiplexer  234  may represent switches. 
     The amplified analog image data from the demultiplexer  234  may enter the 3-column time demultiplexers  236  and  238 . The demultiplexer  236  may time demultiplex the amplified analog image data to proper source lines  128 A,  128 B, and  128 C. The demultiplexer  238  may time demultiplex the amplified analog image data to source lines  128 D,  128 E, and  128 F. To achieve the polarities illustrated in  FIG. 17 , all of the first image data  222  will not pass through the same source amplifier  228  or  230 . Rather, the R 1  data is switched through the positive source amplifier  228  before the G 1  and B 1  image data are switched through the negative source amplifier  230 . The second image data  224  will undergo similar switches. Namely, the image data R 2  is switched through the negative source amplifier  230  before the image data G 2  and B 2  are switched through the positive source amplifier  228 . 
     Switching the image data  222  and  224  through the driving circuitry  220  in this way may be relatively complex. Moreover, it may be relatively electrically costly to alternate between passing data between the positive source amplifier  228  and negative source amplifier  230 . Accordingly, other manners of performing 3-column inversion are described with reference to  FIGS. 18-25 . Turning to  FIG. 18 , a display panel layout  250  includes superpixels  252 A and  252 B. The superpixels  252  of the display panel layout  250  are arranged in red-blue-green order rather than the typical red-green-blue order. Thus, in the display panel layout  250 , blue pixels remain surrounded by pixels of the same polarity. Since the blue pixels are surrounded by pixels of the same polarity, the transmittance of the blue pixels will be enhanced in relation to that of the red and green pixels, which are adjacent to at least one pixel driven at opposite polarity. 
     To achieve the 3-column inversion illustrated in  FIG. 18 , driving circuitry  260  of  FIG. 19  may be employed. The driving circuitry  260  of  FIG. 19  may increase efficiency over the driving circuitry  220  of  FIG. 17 . In the example of  FIG. 19 , the image data supplied may be reordered from the red-green-blue order. Specifically, first image data  262  corresponding to the first superpixel  252 A may be ordered in a red-blue-green order (e.g., R 1 , B 1 , G 1 ). Likewise, second image data  264  may also be ordered in a red-blue-green order (e.g., R 2 , B 2 , G 2 ). The first and second image data  262  and  264  may respectively enter a positive source amplifier  266  and a negative source amplifier  268 . Switches  270  and  272  will allow the source amplifiers  266  and  268  to switch to different demultiplexers  274  and  276  on different frames. Thus, the switches  270  and  272  can remain in place and need not switch multiple times per frame—or even per superpixel  252 . The first demultiplexer  274  demultiplexes image data to program three columns of pixels respectably coupled to the source lines  128 A,  128 B, and  128 C. The second demultiplexer  276  demultiplexers image data to columns of pixels on source lines  128 D,  128 E, and  128 F. The image data  262  and  264  may be supplied to the opposite source amplifiers  266  and  268  on another frame. 
     While the example of  FIG. 19  illustrates 3-column inversion with blue as the central pixel, thereby enhancing the transmittance of blue pixels in relation to the others, other pixels may be centered in other examples. For example, a display panel layout  280  of  FIG. 20  shows green as the center column of pixels in another 3-column inversion scheme. Using the display panel layout  280 , green color transmittance may be enhanced in relation to other pixels of the display  18 . In a display panel layout  282  of  FIG. 21 , red is the center pixel. Using the display panel layout  282 , red color transmittance may be enhanced in relation to other pixels of the display  18 . It should be appreciated that the driving circuitry  260  may be employed to drive the display panel layouts  280  of  FIG. 20  or  282  of  FIG. 21  in substantially the same manner as previously described. 
     Other driving circuitry, such as driving circuitry  290  of  FIG. 22 , may drive the 3-column inversion and display panel layout  150  of  FIG. 8  in a more power efficient manner than the circuitry  220  of  FIG. 17 . The circuitry  290  of  FIG. 22  receives reordered image data  106  that includes first image data  292  and second image data  294 . As illustrated, the first image data  292  and the second image data  294  do not respectively correspond to a single superpixel  252 —instead, the first image data  292  and the second image data  294  each includes at least one pixel from each superpixel  252 A and  252 B. As seen in  FIG. 22 , the first image data  292  contains image data  106  corresponding to G 1 , B 1 , R 2 , and the second image data  294  contains image data  106  corresponding to R 1 , G 2 , B 2 . On one frame, the first image data enters a positive source amplifier  296  and the second image data  294  enters a negative source amplifier  298 . On another frame, the first image data  292  may enter the negative source amplifier  298  and the second image data  294  may enter the positive source amplifier  296 . Switches  300  and  302  alternate which demultiplexer  304  or  306  is coupled to the source amplifiers  296  and  298  for a given frame. Thus, the switches  300  and  302  only are switched on a frame-by-frame basis, reducing power consumption. Two demultiplexers  304  and  306  supply the image data  106  to the columns of the superpixels  152 A and  152 B. As illustrated in  FIG. 22 , the first demultiplexer  304  supplies the image data G 1 , B 1 , and R 2 . The second demultiplexer  306  supplies the image data R 1 , G 2 , and B 2 . 
     Pixel columns of red or green, not only blue as disclosed above, may have enhanced transmittance in relation to the that of other pixel colors using other driving circuitry. In a display panel layout  310  of  FIG. 23 , for example, performing 3-column inversion as illustrated will enhance the transmittance of the red pixels in relation to green and blue pixels. Specifically, as shown in  FIG. 23 , columns of red pixels are driven at the same polarity as adjacent columns of green and blue. The change in polarity occurring between blue and green pixel columns will may reduce the transmittance of these pixels near the change in polarity. Since the red pixel is not adjacent to pixels driven at a different polarity, the red pixel will not suffer the same loss of transmittance. Instead, the transmittance of the red pixel will appear enhanced in relation to the transmittance of the other pixels. 
     Two superpixels  312 A and  312 B are illustrated in  FIG. 23 , and may be driven using driving circuitry  320  shown in  FIG. 24 . The driving circuitry  320  of  FIG. 24  may receive reordered image data  106 , such as first image data  322  and second image data  324 . For one frame, the first image data  322  feeds into a negative source amplifier  326  and the second image data  324  feeds into a positive source amplifier  328 . On another frame, the first image data  322  feeds into the positive source amplifier  328  and the second image data  324  feeds into the negative source amplifier  326 . Switches  330  and  332  couple the source amplifiers  326  and  328  to respective demultiplexers  334  and  336 . Thus, for example, the first image data  322  may pass through the negative source amplifier  326  to the columns R 1 , G 1 , and B 2 . Likewise, the second image data  324  may pass through the positive source amplifier  328  to the columns B 1 , R 2 , and G 2 . The switches  330  and  332  may alternate on different frames to invert the polarity at which the various columns of pixels are driven. 
     A flowchart  340  of  FIG. 25  represents one way to drive the display  18  using the driving circuitry  260  of  FIG. 19 ,  290  of  FIG. 22 ,  320  of  FIG. 24 , as well as similar variations. The flowchart  340  may begin when image data is determined in the processor(s)  12  of the electronic device  10 . This image data  106  may be provided to the timing controller  110 , at which point the timing controller  110  may reorder the image data  106  as appropriate for the driving circuitry to which it will be given (block  344 ). Alternatively, the processor(s)  12  may reorder the image data  106  before providing the image data  106  to the timing controller  110 . Thereafter, the driving circuitry (e.g.,  260 ,  290 , or  320 ) may drive the pixels  60  of the display  18  using the reordered image data  106  (block  346 ). 
     Other column inversion schemes are contemplated. For example, a display panel layout  350  shown in  FIG. 26  illustrates a 2/1-column inversion scheme. As used herein, a “2/1-column inversion scheme” describes a hybrid of a 2-column inversion scheme and a 1-column inversion scheme. In the examples that follow in  FIGS. 26-28 , a subset of the pixels  60  is shown on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . Each pixel  60  modulates light through a red (R), green (G), or blue (B) filter. 
     In the example of  FIG. 26 , all columns of red pixels are supplied with data driven at one polarity, and columns of blue and green pixels are driven at the opposite polarity. Since the columns of red pixels are surrounded on both sides to columns of pixels driven at an opposite polarity from the column of red pixels, the transmittance of the columns of red pixels will be relatively less than the transmittances of the other columns of pixels—only one adjacent side of the green and blue pixels will be driven at an opposite polarity. Accordingly, the 2/1-column inversion scheme shown in  FIG. 26  may also be referred to as 2/1-column inversion (G, B) to indicate that green pixels and blue pixels have slightly increased transmittance in relation to red pixels. Two superpixels  352 A and  352 B are shown in  FIG. 26 . These superpixels  352 A and  352 B will be illustrated in an example of driving circuitry described below with reference to  FIG. 29 . 
       FIGS. 27 and 28  similarly illustrate examples of 2/1-column inversion.  FIG. 27 , for instance, illustrates a display panel layout  360  employing 2/1-column inversion (R, B). That is, the 2/1-column inversion appearing in  FIG. 27  drives the columns of green pixels at one polarity and drives the columns of red and blue pixels at the other polarity. As such, adjacent red and blue pixel columns will have slightly higher transmittances than the green pixel columns. Specifically, the green pixel columns may be fully surrounded by columns of pixels driven at the polarity opposite than that at which the green pixels are driven. Since only one adjacent side of the columns of red and blue pixels will be driven at an opposite polarity, red and blue pixels will have slightly higher transmittances than the green pixels in the display panel layout  360 . Similarly, a display panel layout  370  of  FIG. 28  illustrates a manner of 2/1-column inversion (R, G). The display panel layout  370  of  FIG. 28  is substantially the same as the display panel layout  350  of  FIGS. 26 and 360  of  FIG. 27 , except that the polarities of the columns of pixels are selected as illustrated in  FIG. 28 . This configuration may cause the transmittances of the red and green columns of pixels to be enhanced over the transmittances of the columns of blue pixels. 
     A variety of driving circuitry may be used to achieve the 2/1-column inversion schemes illustrated in  FIGS. 26-28 . For example, as shown in  FIG. 29 , the driving circuitry  220  (originally described with reference to  FIG. 17 ) may be used to achieve the 2/1-column inversion (G, B) shown in  FIG. 26 . Specifically, as seen in  FIG. 29 , first image data  222  and second image data  224  of the image data  106  may be supplied, in a normal order, through the positive source amplifier  228  and/or negative source amplifier  230 . The image data  106  may be switched in a suitable manner so as to program the superpixels  352 A and  352 B in the polarities shown in  FIG. 29 . It may be noted that the elements of the driving circuitry  220  shown in  FIG. 29  are discussed above with reference to  FIG. 17 , and therefore are not discussed here. 
     Although the driving circuitry  220  may be used to achieve any 2/1-column inversion schemes, the requirement of polarity switches through the positive source amplifier  228  and/or negative source amplifier  230  may be electrically costly. These polarity switches are illustrated in a timing diagram  380  of  FIG. 30 . Specifically, the timing diagram  380  illustrates the image data  106  passing through the driving circuitry  220  in temporal order. That is, the image data  106  may be supplied in the order R 1 (+), G 1 (−), B 1 (−), R 2 (+), G 2 (−), B 2 (−), and so on, repeating each row (or scan line) of the frame. Thus, image data  106  is shown for a first scan line  382  and second scan line  384 . Polarity switches  386  occur between R 1  and G 1 , B 1  and R 2 , and R 2  and G 2  of the first scan line  382 , and between B 2  and R 1  of the second scan line  384 . In other words, for each scan line  382  or  384 , a total of four polarity switches  386  may take place. These polarity switches  386  are electrically costly and power would be conserved if the number of polarity switches  386  could be decreased. 
     Another timing diagram  390 , shown in  FIG. 31 , presents such an alternative manner of driving the display  18  to reduce the number of polarity switches  386 . In the timing diagram  390  of  FIG. 31 , the image data  106  of each scan line  382  and  384  is supplied in a different order. In the timing diagram  390 , the order appears as follows, but may be any other suitable order to reduce the number of polarity switches  386 : R 1 (+), G 1 (−), B 1 (−), B 2 (−), G 2 (−), R 2 (+). Thus, polarity switches  386  occur between R 1  and G 1  and G 2  and R 2  of each scan line. In the timing diagram  390  of  FIG. 31 , the number of polarity switches  386  to achieve the same column inversion scheme achieved with the timing diagram  380  of  FIG. 30  is reduced by half. 
     In some embodiments, the driving circuitry  220  may be modified slightly to drive the display  18  in the manner suggested by the timing diagram  390  of  FIG. 31 . One example of such driving circuitry appears as driving circuitry  400  of  FIG. 32 . The driving circuitry  400  is substantially the same as the driving circuitry  220 , with a few changes. For example, as shown in  FIG. 32 , the image data  222  is supplied in a traditional order, but second image data  402  is reordered. Namely, in the second image data  402 , red pixel data is swapped with the blue pixel data, such that the order is as follows: B 2 , G 2 , R 2 . It should be appreciated that the second image data  402  may be so ordered, for example, by an image data reordering component  120  of the display  18 , as discussed above with reference to  FIG. 7 . Additionally or alternatively, the second image data  402  may be so ordered by the processor(s)  12  before being supplied to the display  18 . 
     The driving circuitry  400  of  FIG. 32  also differs from the driving circuitry  220  of  FIG. 17  in that, while the first demultiplexer  236  maintains the same manner of operation, the demultiplexer  238  has been replaced with a demultiplexer  404 . The demultiplexer  404  reverses the order in which the R 2  and B 2  image data of the superpixel  352 B are time demultiplexed to the driving circuitry  400 . As a result, the image data  106  may pass through the driving circuitry  400  with a reduced number of polarity switches  386  as compared to the driving circuitry  220 . 
     A different display panel layout  410 , as shown in  FIG. 33 , may also effect the driving order discussed above with reference to the timing diagram  390  of  FIG. 31 . In the example of  FIG. 33 , a subset of the pixels  60  is shown on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . Each pixel  60  modulates light through a red (R), green (G), or blue (B) filter. As apparent in the subpixel arrangement of two adjacent superpixels  412 A and  412 B, the component subpixels of every superpixel is reverse from the superpixel before and after it. Thus, the component subpixels of the first superpixel  412 A appear in red-green-blue order and the component subpixels of the second superpixel  412 B appear in blue-green-red order. The display panel layout  410  of  FIG. 33  may be said to be performing 4/2-column inversion, since groups of two columns of pixels (adjacent red (R) pixels) of one polarity and groups of four columns (adjacent green (G), blue (B), blue (B), and green (G) pixels) of another polarity are formed. The 4/2-column inversion may have the effect of enhancing the transmittance of blue pixels in relation to others, since blue pixels are wholly surrounded by pixels driven at the same polarity. 
     Driving circuitry  420  of  FIG. 34  may be used to drive the display  18  to achieve the 4/2-column inversion shown in  FIG. 33 . The driving circuitry  420  may be substantially the same as the driving circuitry  220 , except that the order of the second image data  402  is changed and the second demultiplexer  238  couples to the pixels of the superpixel  412 B. As such, like elements previously described are not discussed here. It should be appreciated that the second image data  402  may be ordered as shown in  FIG. 34 , for example, by an image data reordering component  120  of the display  18 , as discussed above with reference to  FIG. 7 . Additionally or alternatively, the second image data  402  may be so ordered by the processor(s)  12  before being supplied to the display  18 . Additionally, it may be seen that the order of pixel columns in the superpixel  412 B is reversed from a typical image data order. As a result, the image data  106  may pass through the driving circuitry  400  to carry out the timing diagram  390  of  FIG. 31 . 
     An alternative arrangement to reduce polarity switches  386  while carrying out 2/1-column inversion (R, B) or 4/2-column inversion (B) appear in  FIGS. 35 and 36 . Specifically, a timing diagram  422  of  FIG. 35  illustrates the timing of image data passing through driving circuitry for 2/1-column inversion (R, B) as illustrated in  FIG. 27 . In the timing diagram  422  of  FIG. 35 , the image data  106  is supplied in the following order: G 1 (+), R 1 (−), B 1 (−), B 2 (−), R 2 (−), G 2 (+). Polarity switches  386  occur in only two places per scan line—between G 1  and R 1  and R 2  and G 2 . It should be appreciated that this reordered image data  106  of  FIG. 35  can be handled by driving circuitry similar to that of  FIG. 32 , in which the ultimate demultiplexers handling each superpixel are arranged to reduce the number of polarity switches. 
     Alternatively, the timing diagram  422  of  FIG. 35  may be effected using a display panel layout  424  to carry out 4/2-column inversion (B), as shown in  FIG. 36 . In the example of  FIG. 36 , a subset of the pixels  60  is shown on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . Each pixel  60  modulates light through a red (R), green (G), or blue (B) filter. In the display panel layout  424 , the component subpixels of every superpixel is reverse from the superpixel before and after it. For example, the component subpixels of the first superpixel appear in green-red-blue order and the component subpixels of the second superpixel appear in blue-red-green order. This pattern may continue throughout the display panel  118 . The display panel layout  424  of  FIG. 36  may be said to be performing 4/2-column inversion (B), since groups of two columns of pixels (adjacent green (G) pixels) of one polarity and groups of four columns (adjacent red (R), blue (B), blue (B), and red (R) pixels) of another polarity are formed. The 4/2-column inversion may have the effect of enhancing the transmittance of blue pixels in relation to others, since blue pixels are wholly surrounded by pixels driven at the same polarity. 
     Similarly, an arrangement to reduce polarity switches  386  while carrying out 2/1-column inversion (R, G) or 4/2-column inversion (R) appear in  FIGS. 37 and 38 . Specifically, a timing diagram  426  of  FIG. 37  illustrates the timing of image data passing through driving circuitry for 2/1-column inversion (R, G) as illustrated in  FIG. 28 . In the timing diagram  422  of  FIG. 35 , the image data  106  is supplied in the following order: R 1 (−), G 1 (−), B 1 (+), B 2 (+), G 2 (−), R 2 (−). Polarity switches  386  occur in only two places per scan line—between G 1  and B 1  and B 2  and G 2 . It should be appreciated that this reordered image data  106  of  FIG. 37  can be handled by driving circuitry similar to that of  FIG. 32 , in which the ultimate demultiplexers handling each superpixel are arranged to reduce the number of polarity switches. 
     Alternatively, the timing diagram  426  of  FIG. 37  may be effected using a display panel layout  428  to carry out 4/2-column inversion (R), as shown in  FIG. 38 . In the example of  FIG. 36 , a subset of the pixels  60  is shown on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . Each pixel  60  modulates light through a red (R), green (G), or blue (B) filter. In the display panel layout  424 , the component subpixels of every superpixel is reverse from the superpixel before and after it. For example, the component subpixels of the first superpixel appear in red-green-blue order and the component subpixels of the second superpixel appear in blue-green-red order. This pattern may continue throughout the display panel  118 . The display panel layout  424  of  FIG. 36  may be said to be performing 4/2-column inversion (R), since groups of two columns of pixels (adjacent green (B) pixels) of one polarity and groups of four columns (adjacent green (G), red (R), red (R), and green (G) pixels) of another polarity are formed. This 4/2-column inversion may have the effect of enhancing the transmittance of red pixels in relation to others, since red pixels are wholly surrounded by pixels driven at the same polarity. 
     Before continuing, it should be noted that many other variations of 2/1-column inversion and 4/2-column inversion are contemplated. Indeed, the examples discussed above are intended merely to represent some of the ways in which 2/1-column inversion and 4/2-column inversion may be carried out with a reduced number of polarity switches in driving circuitry. 
     Indeed, another example of driving circuitry to perform 2/1-column inversion appears in  FIG. 39 . In  FIG. 39 , driving circuitry  430  may consume relatively less power than conventional driving techniques by joining only one source amplifier to one demultiplexer per frame. Specifically, three groups of image data  106 —first image data  432 , second image data  434 , and third image data  436 —may be provided to source amplifiers  438 ,  440 , and  442 . In the example of  FIG. 39 , a negative source amplifier  438  receives the second image data  434 , a positive source amplifier  440  receives the first image data  432 , and a negative source amplifier  442  receives the third image data  436 . As illustrated, the first image data  432 , second image data  434 , and third image data  436  respectively include the image data  106  associated with the red pixels of the superpixel  352 A and  352 B (e.g., R 1  and R 2 ), the green pixels (e.g., G 1  and G 2 ), and the blue pixels (e.g., B 1  and B 2 ). 
     Switches  444  couple the source amplifiers  438 ,  440 , and  442  to different respective 2-column demultiplexers  446 ,  448 , and  450 . The switches  444  occasionally (e.g., once for each frame) vary how the source amplifiers  438 ,  440 , and  442  connect to the demultiplexers  446 ,  448 ,  450 . Thus, for one frame, the demultiplexer  446  supplies amplified image data to the red pixels of the superpixels  352 A and  352 B. The demultiplexer  448  supplies amplified image data to the green pixels of the superpixels  352 A and  352 B. The demultiplexer  450  supplies amplified image data to the blue pixels of the superpixels  352 A and  352 B. 
     On other frames, the switches  444  may connect the source amplifiers  438 ,  440 , and  442  and demultiplexers  446 ,  448 ,  450  in different ways. Likewise, the first image data  432 , second image data  434 , and third image data  436  may be provided to different of the source amplifiers  438 ,  440 , and  442 . By way of example, for every three frames, the first image data  432 , second image data  434 , and third image data  436  may be amplified into each polarity at least once (e.g., amplified twice to a negative value via the source amplifiers  438  and/or  442  and amplified once to a positive value via the source amplifier  440 ). 
     As mentioned above, because the driving circuitry  430  of  FIG. 39  includes only three source amplifiers, the driving circuitry  430  may drive each column at one polarity for two frames before switching to the opposite polarity for the third frame. By adding another source amplifier, however, many other column inversion schemes may also be performed. For example,  FIG. 40  illustrates driving circuitry  460  that, while similar to that of  FIG. 39 , includes an additional positive source amplifier  462  and switches  464 . Like-numbered elements from other drawings that also appear in  FIG. 40  may be understood to operate in substantially the same way. The switches  464  may switch the source amplifiers  438 ,  440 ,  442 , and  462  on occasion (e.g., on a frame-by-frame basis). 
     Using the driving circuitry  460  of  FIG. 40 , substantially any 2/1-column inversion schemes may be performed. Indeed, the driving circuitry  460  of  FIG. 40  may carry out any of the 2/1-column inversion schemes described above with reference to  FIGS. 26-28 . The driving circuitry  460  of  FIG. 40  may be able to carry out these column inversion schemes in a more efficient way than the driving circuitry  220 , since each demultiplexer  446 ,  448 ,  450  may supply amplified image data to the pixels through a single source amplifier each frame. It should be appreciated that the image data  106  may be reordered from an original image data order before being handled by the driving circuitry  430  of  FIG. 39  or  460  of  FIG. 40 . An image data reordering component  120  of the display  18 , as discussed above with reference to  FIG. 7 , or the processor(s)  12  may reorder the image data  106  in any suitable order (e.g., as illustrated in  FIGS. 39 and 40 ). 
     Other driving circuitry may operate on similar principles as the driving circuitry  430  of  FIG. 39  or  460  of  FIG. 40 . Driving circuitry  470  of  FIG. 41 , for instance, may similarly include one source amplifier per demultiplexer. As seen in  FIG. 41 , the driving circuitry  470  may drive 12 columns of pixels that include a first red pixel (R 1 ), a first green pixel (G 1 ), a first blue pixel (B 1 ), a second red pixel (R 2 ), a second green pixel (G 2 ), a second blue pixel (B 2 ), a third red pixel (R 3 ), a third green pixel (G 3 ), a third blue pixel (B 3 ), a fourth red pixel (R 4 ), a fourth green pixel (G 4 ), and a fourth blue pixel (B 4 ). Source amplifiers  472 ,  474 ,  476 ,  478 ,  480 , and  482  may couple via switches  484  to respective demultiplexers  486 ,  488 ,  490 ,  492 ,  494 , and  496 . The switches  484  may change occasionally (e.g., on a frame-by-frame basis) to invert the polarities of the columns of pixels according to any suitable column inversion scheme. It should be appreciated that the image data  106  may be reordered from an original image data order before being handled by the driving circuitry  470  of  FIG. 41 . An image data reordering component  120  of the display  18 , as discussed above with reference to  FIG. 7 , or the processor(s)  12  may reorder the image data  106  in any suitable order (e.g., as illustrated in  FIGS. 39 and 40 ). Upon programming different frames onto the display  18 , different image data  106  may be supplied to different ones of the source amplifiers  472 ,  474 ,  476 ,  478 ,  480 , and  482  of the driving circuitry  470 . 
     The demultiplexers  486 ,  488 ,  490 ,  492 ,  494 , and  496  respectively couple to the same color pixels in every other superpixel. For example, the demultiplexer  486  couples to pixels R 1  and R 3 , the demultiplexer  488  couples to pixels G 1  and G 3 , and the demultiplexer  490  couples to pixels B 1  and B 3 , and so forth. In this way, the driving circuitry  470  may be used to drive the pixels of the display  18  using, among other things, any symmetrical column inversion schemes. As used herein, “symmetrical column inversion” refers to column inversion in which an equal number of columns of pixels are driven at positive polarities as negative polarities for every two superpixels. For example, the driving circuitry  470  may perform any form of 3-column, 2-column, or even 1-column inversion discussed in this disclosure. In the example of  FIG. 41 , the driving circuitry  470  is shown to perform 3-column inversion (blue center pixel), which may enhance the transmittance of the blue pixels of the display  18  in relation to the red and green pixels. 
     The driving circuitry  470  also may perform 1-column inversion in the manner illustrated in  FIG. 42 .  FIG. 42  represents a display panel layout  500  in which adjacent columns of pixels are driven at opposite polarities. In the example of  FIG. 42 , a subset of the pixels  60  is shown on the display panel  118 . Three gate lines  126 A-C are shown to supply activation signals to three corresponding rows of pixels  60  and ten source lines  128 A-J supply data signals to ten corresponding columns of pixels  60 . Each pixel  60  includes a respective TFT  130  and a pixel electrode  134 . Each pixel  60  modulates light through a red (R), green (G), or blue (B) filter. With a 1-column inversion scheme, such as that shown in  FIG. 42 , two adjacent superpixels  502 A and  502 B will have pixels of the same color driven at opposite polarities. This pattern will repeat for every two adjacent superpixels. 
     Although 1-column inversion provides reduced transmittance from all pixels of the display, all adjacent columns of pixels are driven at opposite polarities. As a result, all columns of pixels in 1-column inversion will have reduced transmittance compared to a configuration in which at least some columns of pixels are not completely adjacent to pixels of opposite polarities (e.g., 3-column inversion, 2-column inversion, or 2/1-column inversion). Occasionally providing 1-column inversion, however, could produce superior color reproduction of the display panel  18 . In particular, varying which column inversion scheme is used—for example, selecting a particular column inversion scheme to apply during the manufacture of the display  18  or applying a duty ratio of different column inversion schemes—may cause the white point of the display  18  to shift. As mentioned above, the term white point refers to the color emitted by the display  18  when programmed to display the color white. 
     One example of a white point of the display  18  is generally illustrated in  FIG. 44 , which illustrates a color space plot  510 . Before continuing further, it should be noted that the white point of the display  18  may be adjusted through software processing to change the values of the image data  106  entering the display  18 , but doing so may cause some image information to be lost. In addition or alternatively to software processing, the white point of the display  18  may be adjusted using the column inversion scheme(s) applied in the display  18 . As will be discussed below, the column inversion scheme may be selected to be static or dynamic. As used herein, a static column inversion scheme is one that has been selected to run generally exclusively and may be selected relatively few times (e.g., only once at manufacture). A dynamic column inversion scheme is one that may vary over time to adjust the white point (e.g., a duty ratio of multiple column inversion schemes). 
     The color space plot  510  of  FIG. 44  illustrates a CIE 1976 color space in color units of u′ and v′. Namely, an ordinate  512  illustrates the v′ axis and an abscissa  514  illustrates the u′ axis. Appearing in the plot  510  is the CIE 1976 color space. As should be appreciated by those of ordinary skill in the art, the color space  516  represents a range of color values. Within the color space  516  fall a range of acceptable white points  518  of the display  18 . The range of acceptable white points  518  is intended to generally be schematic in  FIG. 44 . That is, in an actual implementation, a much smaller range of acceptable white points  518  could be chosen. Moreover, the acceptable white points  518  may be located elsewhere in the color space  516 . 
     Different displays  18  will generally have different white points within the range of acceptable white points  518 . The different white points are generally caused by differences in the backlight assemblies  68  and the display panels  118  of different displays  18 . Different backlight assemblies  68 , for instance, may have LEDs that emit slightly different colors of light. In addition, differences in the diffusers  104  of the different backlight assemblies  68  may cause the color of light from the LEDs to shift, further varying the color of the light. Finally, differences in the display panels  118  of the displays  18  may further cause various color shifts. As such, the likelihood that all displays  18  will have the same white point is extremely slim. 
     Particular column inversion schemes may have the effect of shifting the white point from a starting white point (e.g., color point  520 ) of a display  18  more toward a desired white point. In various embodiments, the starting white point may occur in various locations within the range of acceptable white points  518 . The desired white point may be a color point within the range of acceptable white points  518  that may most approximate the color white when seen by the human eye. The color point  520  represents a white point that may result when 1-column inversion is used. Since 1-column inversion reduces the transmittances of all colulmns of pixels substantially equally, the color that results after 1-column inversion will be substantially the same as that which would occur without column inversion. A color point  522  illustrates a white point that may result when 3-column inversion (red center pixel) is used, which may enhance the transmittance of red pixels in relation to the others, thereby shifting the starting color point  520  toward red. A color point  524  illustrates a white point that may result when 3-column inversion (green center pixel) is used, which may enhance the transmittance of green pixels in relation to the others, thereby shifting the starting color point  520  toward green. Finally, a color point  526  illustrates a white point that may result when 3-column inversion (blue center pixel) is used, which may enhance the transmittance of blue pixels in relation to the others, thereby shifting the starting color point  20  toward blue. 
     As will be discussed below, a particular column inversion scheme may be selected to keep the starting white point of the display  18  in place (e.g., at the color point  520 ) or to shift the starting white point more toward a desired white point (e.g., to the color points  522 ,  524 , or  526 ). Additionally or alternatively, a duty ratio of different column inversion schemes may cause a shift to a particular point  520 ,  522 ,  524 , or  526  during particular periods of time. By varying the column inversion schemes applied over time, the average white point may more closely approximate the desired white point. Various ways of more closely approaching the desired white point will be discussed further below. 
     If a display panel  18  includes driving circuitry such as the driving circuitry  220  or  470 , any suitable column inversion having an equal number of image data driven at one polarity as driven at the other polarity may be employed. Suitable column inversion schemes may include, for example, 1-column inversion or 3-column inversion. Although 1-column inversion may not affect the white point of the display, 3-column inversion may do so in a manner that emphasizes red, green, or blue in relation to the other pixels. In addition, the driving circuitry  220  and its variants may perform 2/1-column inversion, which may similarly emphasize red and green over blue, green and blue over red, or red and blue over green. 
     As such, the column inversion scheme may be selected cause the white point of the display  18  to shift closer to a desired white point. For example, as shown by a flowchart  530  of  FIG. 45 , during or after manufacture, a display  18  may be programmed to display the color white, and the white point associated with each column inversion scheme measured. The white point of the display  18  may be measured while the display  18  is performing a 1-column inversion scheme (block  532 ), a 3-column inversion scheme (green center pixel) (block  534 ), a 3-column inversion scheme (red center pixel) (block  536 ), and a 3-column inversion scheme (green center pixel) (block  538 ). 
     Thereafter, the display  18  may be programmed to perform the 1-column inversion scheme or the one of the 3-column inversion schemes that produces a white point closes to the desired white point (block  540 ). For example, the column inversion selection component  124  may be programmed and/or the white point selection component  122  may be programmed to cause the display driver circuitry of the display  18  to perform the selected column inversion. Thus, in a product-manufacturing setting, some of the displays  18  may have starting white points more red, green, or blue than the desired white point. The displays  18  programmed in the manner of the flowchart  530  of  FIG. 45  may perform different column inversion depending on their respective starting white points to shift the white point of the display  18  more closely to the desired white point. 
     Additionally or alternatively, other column inversion schemes may be employed to shift the white point of a display  18  toward a desired white point. For example, as shown by a flowchart  550  of  FIG. 46 , during or after manufacture, a display  18  may be programmed to display the color white, and the white point associated with each column inversion scheme measured. The white point of the display  18  may be measured while the display  18  is performing a 2/1-column inversion scheme (red, blue) (block  552 ), a 2/1-column inversion scheme (red, green) (block  554 ), and a 2/1-column inversion scheme (blue, green) (block  556 ). In other embodiments, any suitable column inversion schemes may be performed and tested. 
     Thereafter, the display  18  may be programmed to perform any of these column inversion schemes that produces a white point closes to the desired white point (block  558 ). For example, the column inversion selection component  124  and/or the white point selection component  122  may be programmed to cause the display driver circuitry of the display  18  to perform the selected column inversion. Thus, in a product-manufacturing setting, some of the displays  18  may have starting white points more red, green, or blue than the desired white point. The displays  18  programmed in the manner of the flowchart  550  of  FIG. 46  may perform different column inversion depending on their respective starting white points to shift the white point of the display  18  more closely to the desired white point. 
     Before continuing further, it should also be understood that variations of the above-described methods are contemplated. For example, in other embodiments, rather than test the resulting white points that arise when different column inversion schemes are applied, only the white point without column inversion or with only 1-column inversion may be tested. From this value, a particular column inversion scheme that is likely to shift the white point toward the desired white point may be determined. For instance, the starting white point of the display  18  may be compared to the desired white point to obtain a color space vector. The column inversion scheme that most closely approximates the color space vector may be selected in an effort to shift the white point of the display  18  toward the desired white point. 
     As discussed above, some display panels  118  and/or driving circuitry associated with the display panels  118  may carry out one particular column inversion scheme. For example, some display panels  118  and/or driving circuitry associated with the display panels  118  may carry out 3-column inversion with a particular center pixel color whose transmittance is enhanced in relation to other colors. In another example, some display panels  118  and/or driving circuitry associated with the display panels  118  may carry out 2/1-column inversion in which two colors of pixels has an enhanced transmittance in relation to that of the other color. Since the color of light emitted by the backlight assembly  68  may impact the ultimate color of the white point emitted by the display  18 , certain backlight assemblies  68  may be paired to certain display panels  118  and/or driving circuitry associated with the display panels  118 . 
     A color space plot  570  of  FIG. 47  illustrates a relationship between the color of the light emitted by different backlight assemblies  68  and the ultimate colors emitted by the display  18 . The color space plot  570  of  FIG. 47  illustrates the CIE 1976 color space  516  in units of u′ and v′. Namely, an ordinate  512  illustrates the v′ axis and an abscissa  514  illustrates the u′ axis. Illustrated within the color space  516  shown in  FIG. 47  is a range  576  of backlight assembly light emission colors. The range  576  generally describes the color of light emitted by the backlight assembly  68 . For example, light emitted by four different backlight assemblies  68  may include a first range  578 A, a second range  578 B, and a third range  578 C. As the light emitted from a backlight assembly  68  passes through other layers of a display  18 , the emitted color of light may shift to an area within the range of acceptable white points  518 . For instance, the first backlight range of colors  578 A may translate to a first range  580 A of light emitted by the display  18 . Similarly, the second range  578 B of light emitted by the backlight assembly  68  may translate to a second range  580 B of light emitted by the display  18 . Finally, in another example, light emitted by the backlight assembly  68  in the third range  578 C generally may translate to a range  580 C of light through the display  18 . As shown in the example of  FIG. 47 , light emitted by backlight assemblies  68  in a more red, blue, or green segment of the range  576  may likewise translate to a white point within the range of acceptable white points that are generally more red, blue, or green. 
     As shown in a flowchart  590  of  FIG. 48 , the color of light emitted by the backlight assembly  68  may be used to anticipate the likely color of the light emitted by the display  18  and select a corrective column inversion scheme during the manufacture of the display  18 . In particular, a particular backlight assembly  68  may be paired to a particular display panel  118 , thereby producing a display  18  with an improved white point of the display  18 . The flowchart  590  may begin when backlight assemblies  68  of displays are manufactured (block  592 ). Other components of the displays  18  may be manufactured with display panels  118  and driver circuitry that can carry out at least one of the 3-column inversion schemes discussed above (block  594 ). For instance, in one example, one-third of the display panels  118  may have display panel layouts and driving circuitry to perform 3-column inversion with a blue center pixel, one-third of the display panels  118  may have display panel layouts and driving circuitry to perform 3-column inversion with a red center pixel, and one-third of the display panels  118  may have display panel layouts and driving circuitry to perform 3-column inversion with a green center pixel. 
     The color of light emitted by the backlight assemblies  68  may be measured (block  596 ), from which the likely ultimate white point of the display  18  may be estimated. Thus, using the color of the light emitted by the backlight assemblies  68 , different backlight assemblies  68  and display panels  118  may be mated together such that the resulting combination is likely to be near a target white point (block  598 ). For example, a backlight assembly  68  that tends to emit more light in a red and/or green direction may be mated to a display panel that employs 3-column inversion (blue center pixel) to cause the white point to move away from red and green, and toward blue. A backlight assembly  68  that tends to emit more light in a blue and/or green direction may be mated to a display panel that employs 3-column inversion (red center pixel) to cause the white point to move away from blue and green, and toward red. Likewise, a backlight assembly  68  that tends to emit more light in a blue and/or red direction may be mated to a display panel that employs 3-column inversion (green center pixel) to cause the white point to move away from blue and red, and toward green. 
     In the examples discussed above, the displays  18  generally may perform substantially one column inversion scheme until reprogrammed. As such, the column inversion scheme may be referred to as “static” column inversion, which may shift the white point of the display  18  more closely to the desired white point. Alternatively, the display  18  may perform a duty ratio of several column inversion schemes in what may be referred to as “dynamic” column inversion. It should be appreciated, however, that the example of  FIG. 45  may additionally or alternatively employ dynamic column inversion in the manner discussed below. 
     One example of dynamic column inversion appears in a flowchart  610  of  FIG. 49 . The flowchart  610  may begin when the white point of a display  18  may be measured using 1-column inversion (block  612 ), 3-column inversion (green center pixel) (block  614 ), 3-column inversion (red center pixel) (block  616 ), and 3-column inversion (blue center pixel) (block  618 ). Measuring the white points of the display  18  when particular column inversion schemes are applied may indicate the extent to which the white point may be affected by particular column inversion schemes. By applying certain column inversion schemes according to a particular duty ratio, the white point may be altered from its starting white point by some particular amount. Thus, the display  18  may be programmed to perform a duty ratio of column inversion to more closely approach a desired white point (block  620 ). By way of example, the white point selection component  122  and/or column inversion selection component  124  may be programmed to cause the driving circuitry of the display  18  to perform the particular duty ratio of column inversion. 
     One example of a duty ratio of column inversion appears in  FIGS. 50-52 . In  FIG. 50 , a chart  630  includes columns that indicate the polarity of image data supplied to six pixels, shown as R 1 , B 1 , G 1 , R 2 , G 2 , and B 2 . Rows refer to the polarity of the image data for specific frames  1 - 10  over time. In the example of  FIG. 50 , a duty ratio of 2:1 (3-column inversion:1-column inversion) is applied. Over the ten frames illustrated, during frames  1 - 4  and  7 - 10 , 3-column inversion (blue center pixel) is applied, while during frames  5  and  6 , 1-column inversion is applied. Where a pixel is adjacent to two other pixels driven at the same polarity as itself during a particular frame in the chart  630 , the polarity is circled. In frames  1 - 4  and  7 - 10 , for example, the pixels B 1  and B 2  are surrounded by data of like polarities, and so are circled. During frames in which pixels are circled in  FIG. 50 , the transmittances of these pixels in relation to the other pixels may be slightly greater. Thus, during frames  1 - 4  and  7 - 10 , the blue pixels B 1  and B 2  may have a greater transmittance than otherwise. During these frames, the increased blue transmittance may shift the starting white point in a blue direction. During frames  5  and  6 , however, the starting white point of the display  18  may not be shifted. 
     The column inversion timing shown in the chart  630  may also be illustrated to be the 2:1 (3-column inversion:1-column inversion) duty ratio as seen in a timing diagram  640  of  FIG. 51 . In the timing diagram  640 , a plot  644  shows that either 3-column inversion or 1-column inversion is applied during each frame, which occurs between tick marks on a time axis  642 . During a first four frames (e.g., numeral  646 ), 3-column inversion is applied. During a subsequent two frames (e.g., numeral  648 ), 1-column inversion is applied. 
     In effect, the 2:1 (3-column inversion:1-column inversion) may cause the white point to vary every few frames. The differences over time may be relatively fleeting, however, such that the human eye may average the white points to see an interpolated or average white point. A plot  660  of  FIG. 52  illustrates this effect. The plot  660  illustrates color illustrates several plots in a segment of the CIE 1976 color space in units of u′ and v′. Namely, an ordinate  662  illustrates the v′ axis and an abscissa  664  illustrates the u′ axis. Previously described color points  520 ,  522 ,  524 , and  526  are also shown. As mentioned above, the color point  520  represents a starting white point that may occur when 1-column inversion is applied, the color point  522  represents a white point that may occur when 3-column inversion (red center pixel) is applied, the color point  524  represents a white point that may occur when 3-column inversion (green center pixel) is applied, and the color point  526  represents a white point that may occur when 3-column inversion (blue center pixel) is applied. 
     Accordingly, when the 2:1 (3-column inversion:1-column inversion) duty ratio illustrated in the example of  FIGS. 50 and 51  is applied over six frames, the white point of the display  18  may be the color point  520  during two frames and may be the color point  526  during four frames. The human eye may interpolate between the rapidly switching color points  520  and  526 , effectively causing the white point of the display  18  to be seen as a color point  666 . 
     Other suitable duty ratios of column inversion schemes may be employed to achieve other effective white points. In general, any effective white points between the color points  522 ,  524 , and  526  may be obtained by varying between the different 3-column inversion schemes used to achieve them. For example,  FIGS. 53-55  provide an example involving a duty ratio between two 3-column inversion schemes. Still, it should be appreciated that any suitable number of different column inversion schemes may be employed in a duty ratio. That is, though the examples presented in this disclosure show a duty ratio of two column inversion schemes, other duty ratios may employ 3 or more. 
     In  FIG. 53 , a chart  670  includes columns that indicate the polarity of image data supplied to six pixels, shown as R 1 , B 1 , G 1 , R 2 , G 2 , and B 2 . Rows refer to the polarity of the image data for specific frames  1 - 10  over time. In the example of  FIG. 53 , a duty ratio of 1:1 (3-column inversion (green center pixel):3-column inversion (red center pixel)) is applied. Over the ten frames illustrated, during frames  1 ,  2 ,  5 ,  6 ,  9 , and  10 , 3-column inversion (green center pixel) is applied, while during frames  3 ,  4 ,  7 , and  8 , 3-column inversion (red center pixel) is applied. Where a pixel is adjacent to two other pixels driven at the same polarity as itself during a particular frame in the chart  670 , the polarity is circled. Thus, in frames  1 ,  2 ,  5 ,  6 ,  9 , and  10 , the pixels G 1  and G 2  are surrounded by data of like polarities, and so are circled. Likewise, in frames  3 ,  4 ,  7 , and  8 , the pixels R 1  and R 2  are circled. During frames in which pixels are circled in  FIG. 53 , the transmittances of these pixels in relation to the other pixels may be slightly greater. Thus, during frames  1 ,  2 ,  5 ,  6 ,  9 , and  10 , the green pixels G 1  and G 2  may have a greater transmittance than otherwise, and during frames  3 ,  4 ,  7 , and  8 , the red pixels R 1  and R 2  may have a greater transmission than otherwise. The increased transmittance of these colored pixels may shift the starting white point in a green or red direction, on average, half of the time the display  18  is operating. 
     The column inversion timing shown in the chart  670  may also be illustrated to be the 1:1 (3-column inversion (green center pixel):3-column inversion (red center pixel)) duty ratio as seen in a timing diagram  680  of  FIG. 54 . In the timing diagram  680 , over a time axis  682 , a plot  684  shows that either 3-column inversion (green center pixel) or 3-column inversion (red center pixel) is applied during each frame. Each frame occurs between tick marks on the time axis  642 . During a first two frames (e.g., numeral  686 ), 3-column inversion (green center pixel) is applied. During a subsequent two frames (e.g., numeral  688 ), 3-column inversion (red center pixel) is applied. 
     In effect, the (3-column inversion (green center pixel):3-column inversion (red center pixel)) duty ratio may cause the white point to vary every few frames. The differences over time may be relatively fleeting, however, such that the human eye may average the white points to see an interpolated or average white point. A plot  690  of  FIG. 54  illustrates this effect. The plot  690  illustrates color illustrates several plots in a segment of the CIE 1976 color space in units of u′ and v′. Namely, an ordinate  692  illustrates the v′ axis and an abscissa  694  illustrates the u′ axis. Previously described color points  520 ,  522 ,  524 , and  526  are also shown. As mentioned above, the color point  520  represents a starting white point that may occur when 1-column inversion is applied, the color point  522  represents a white point that may occur when 3-column inversion (red center pixel) is applied, the color point  524  represents a white point that may occur when 3-column inversion (green center pixel) is applied, and the color point  526  represents a white point that may occur when 3-column inversion (blue center pixel) is applied. 
     Accordingly, when the 1:1 (3-column inversion (green center pixel):3-column inversion (red center pixel)) duty ratio illustrated in the example of  FIGS. 53 and 54  is applied over four frames, the white point of the display  18  may be the color point  524  during two frames and may be the color point  522  during two frames. The human eye may interpolate between the rapidly switching color points  522  and  524 , effectively causing the white point of the display  18  to be seen as a color point  696 . 
     Other column inversion schemes than 3-column inversion and 1-column inversion may be chosen in a duty ratio to dynamically adjust the white point of a display  18 . For example, a duty ratio may, additionally or alternatively, employ 2/1-column inversion. One such example of dynamic column inversion using 2/1-column inversion appears in a flowchart  700  of  FIG. 56 . The flowchart  700  may begin when the white point of a display  18  may be measured using 2/1-column inversion (red, blue) (block  702 ), 2/1-column inversion (red, green) (block  704 ), and 2/1-column inversion (green, blue) (block  706 ). Measuring the white points of the display  18  when particular column inversion schemes are applied may indicate the extent to which the white point may be affected by particular column inversion schemes. By applying certain column inversion schemes according to a particular duty ratio, the white point may be altered from its starting white point by some specific amount. Thus, the display  18  may be programmed to perform a duty ratio of column inversion to more closely approach a desired white point (block  708 ). By way of example, the white point selection component  122  and/or column inversion selection component  124  may be programmed to cause the driving circuitry of the display  18  to perform the particular duty ratio of column inversion. 
     One example of a duty ratio of 2/1-column inversion appears in  FIGS. 57-59 . In  FIG. 57 , a chart  720  includes columns that indicate the polarity of image data supplied to six pixels, shown as R 1 , B 1 , G 1 , R 2 , G 2 , and B 2 . Rows refer to the polarity of the image data for specific frames  1 - 10  over time. In the example of  FIG. 57 , a duty ratio of 2:1 (2/1-column inversion (green, blue):2/1-column inversion (red, blue)) is applied. Over the ten frames illustrated, during frames  1 - 4  and  7 - 10 , 2/1-column inversion (green, blue) is applied, while during frames  5  and  6 , 2/1-column inversion (red, blue) is applied. Where a pixel is not surrounded on both sides by two other pixels driven at the opposite polarity as itself during a particular frame in the chart  720 , the polarity is circled. In frames  1 - 4  and  7 - 10 , for example, the pixels G 1 , B 1 , G 2 , and B 2  are circled. In frames  5  and  6 , the pixels R 1 , B 1 , R 2 , and B 2  are circled. During frames in which pixels are circled in  FIG. 57 , the transmittances of these pixels in relation to the other, non-circled pixels may be slightly greater. Thus, during frames  1 - 4  and  7 - 10 , the green and blue pixels may have a greater transmittance than the red pixels. During frames  5  and  6 , the red and blue pixels may have a greater transmittance than the green pixels. 
     The column inversion timing shown in the chart  720  may also be illustrated to be the 2:1 (2/1-column inversion (green, blue):2/1-column inversion (red, blue)) duty ratio as seen in a timing diagram  730  of  FIG. 58 . The timing diagram  730  illustrates, over a time axis  732 , that either 2/1-column inversion (green, blue) or 2/1-column inversion (green, blue) is applied during each frame. Each frame is shown to occur between tick marks on the time axis  732 . During a first four frames (e.g., numeral  736 ), 2/1-column inversion (green, blue) is applied. During a subsequent two frames (e.g., numeral  738 ), 2/1-column inversion (red, blue) is applied. 
     In effect, the 2:1 (2/1-column inversion (green, blue):2/1-column inversion (red, blue)) duty ratio may cause the white point to vary every few frames. The differences over time may be relatively fleeting, however, such that the human eye may average the white points to see an interpolated or average white point. A plot  750  of  FIG. 59  illustrates this effect. The plot  750  illustrates an area of the CIE 1976 color space in units of u′ and v′. Namely, an ordinate  752  illustrates the v′ axis and an abscissa  754  illustrates the u′ axis. Previously described color points  520 ,  522 ,  524 , and  526  are also shown. As mentioned above, the color point  520  represents a starting white point that may occur when 1-column inversion is applied, the color point  522  represents a white point that may occur when 3-column inversion (red center pixel) is applied, the color point  524  represents a white point that may occur when 3-column inversion (green center pixel) is applied, and the color point  526  represents a white point that may occur when 3-column inversion (blue center pixel) is applied. 
     Although not expressly shown, it should be appreciated that different 2/1-column inversion schemes may likewise result in color points other than the starting white point  520 . These other color points would be located off-axis from the red, green, and blue directions, however, since the 2/1-column inversion schemes generally reduce the transmittance of all colors of pixels, two colors of which are reduced less than the third color. Thus, for example, 2/1-column inversion (red, blue) would produce a white point generally between the red and green axes some distance from the starting white point  520 . The magnitude of the distance between such a color point produced by 2/1-column inversion would be less than those of the color points  522  and  524 . 
     Accordingly, when the 2:1 (2/1-column inversion (green, blue):2/1-column inversion (red, blue)) duty ratio illustrated in the example of  FIGS. 57 and 58  is applied over six frames, the white point of the display  18  may be a color point between the green and blue axes during four frames and may be a color point between the blue and red during two frames. The human eye may interpolate between the rapidly switching color points, effectively causing the white point of the display  18  to be seen as a color point  756 . 
     It should be further appreciated that the particular column inversion scheme that may be applied at a given time may be influenced by the processor(s)  12  or other data processing circuitry of the electronic device  10 . For instance, software or firmware of the electronic device  10  may indicate a particular white point or may indicate that the white point of the display  18  to be shifted in a particular color direction. As a result, in some embodiments, the column inversion selection component  120  or the white point selection component  122  of the timing controller  110  may be programmed based on processor(s)  12  or other data processing circuitry of the electronic device  10 . To provide one example, an increase in temperature may cause the white point of the display  18  to shift more toward blue. When the temperature-sensing circuitry  28  detects a particular temperature, the processor(s)  12  may cause the display  18  to use a column inversion scheme that counteracts the impact of the temperature-induced color shift toward blue. Additionally or alternatively, the display  18  may perform a first column inversion scheme or a first duty ratio of column inversion schemes when the temperature is less than a threshold. When the temperature crosses the threshold, the display  18  may perform a second column inversion scheme or a second duty ratio of column inversion schemes that shifts the color of the display away from blue to counteract the impact of the temperature-induced color shift toward blue. 
     The specific embodiments described above have been shown by way of example, and it should be understood that these embodiments may be susceptible to various modifications and alternative forms. It should be further understood that the claims are not intended to be limited to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure.

Metadata:
Filing Date: 20120314
Publication Date: 20150602
Grant Date: 20150602
Priority Date: 20120314
Inventors: XU MING
GE ZHIBING
CHANG SHIH CHANG
CHEN CHENG
BAE HOPIL
GETTEMY SHAWN ROBERT
YAO WEI H.
Assignee: APPLE INC
CPC Classifications: [{"code": "G09G3/3614", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G3/3426", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/006", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2300/0439", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/041", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3413", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G2330/023", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2300/0804", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3614", "inventive": true, "first": false, "tree": "[]"}, {"code": "G09G2320/041", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2320/0242", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2300/0804", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/3413", "inventive": true, "first": true, "tree": "[]"}, {"code": "G09G3/3426", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2300/0439", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G2330/023", "inventive": false, "first": false, "tree": "[]"}, {"code": "G09G3/006", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 49157187