Display panel having crossover connections effecting dot inversion

Information

  • Patent Grant
  • 8035599
  • Patent Number
    8,035,599
  • Date Filed
    Friday, June 6, 2003
    21 years ago
  • Date Issued
    Tuesday, October 11, 2011
    13 years ago
Abstract
A display is disclosed having crossover connections effecting polarity inversion. The display includes a panel comprising a subpixel repeating group having an even number of repeating subpixels in a first direction. The display also includes a driver circuit coupled to the panel to provide image data signals effecting polarity inversion to the panel. The display also includes a plurality of crossover connections from the driver circuit to the columns of the panel such that polarities of same color subpixels in the first direction alternate at a spatial frequency sufficient to abate undesirable visual affects on the panel when an image is displayed thereon; each crossover connection applying the same polarity to each subpixel in the column.
Description
RELATED APPLICATIONS

The present application is related to commonly owned United States patent applications: (1) United States Patent Application Publication No. 2004/0246381 (“the '381 application”) [U.S. patent application Ser. No. 10/455,931] entitled “SYSTEM AND METHOD OF PERFORMING DOT INVERSION WITH STANDARD DRIVERS AND BACKPLANE ON NOVEL DISPLAY PANEL LAYOUTS”, and now issued as U.S. Pat. No. 7,218,301 B2; (2) United States Patent Application Publication No. 2004/0246278 (“the '278 application”) [U.S. patent application Ser. No. 10/455,927] entitled “SYSTEM AND METHOD FOR COMPENSATING FOR VISUAL EFFECTS UPON PANELS HAVING FIXED PATTERN NOISE WITH REDUCED QUANTIZATION ERROR”, and now issued as U.S. Pat. No. 7,209,105 B2; (3) United States Patent Application Publication No. 2004/0246279 (“the '279 application”) [U.S. patent application Ser. No. 10/456,806] entitled “DOT INVERSION ON NOVEL DISPLAY PANEL LAYOUTS WITH EXTRA DRIVERS” and now issued as U.S. Pat. No. 7,187,353 B2; (4) United States Patent Application Publication No. 2004/0246404 (“the '404 application”) [U.S. patent application Ser. No. 10/456,838] entitled “LIQUID CRYSTAL DISPLAY BACKPLANE LAYOUTS AND ADDRESSING FOR NON-STANDARD SUBPIXEL ARRANGEMENTS”; and (5) United States Patent Application Publication No. 2004/0246280 (“the '280 application”) [U.S. patent application Ser. No. 10/456,839] entitled “IMAGE DEGRADATION CORRECTION IN NOVEL LIQUID CRYSTAL DISPLAYS,” which are hereby incorporated herein by reference.


BACKGROUND

In commonly owned United States patents and Published patent applications: (1) U.S. Pat. No. 6,903,754 (“the '754 patent”) [U.S. patent application Ser. No. 09/916,232] entitled “ARRANGEMENT OF COLOR PIXELS FOR FULL COLOR IMAGING DEVICES WITH SIMPLIFIED ADDRESSING,” filed Jul. 25, 2001; (2) United States Patent Publication No. 2003/0128225 (“the '225 application”) [U.S. patent application Ser. No. 10/278,353] entitled “IMPROVEMENTS TO COLOR FLAT PANEL DISPLAY SUB-PIXEL ARRANGEMENTS AND LAYOUTS FOR SUB-PIXEL RENDERING WITH INCREASED MODULATION TRANSFER FUNCTION RESPONSE,” filed Oct. 22, 2002; (3) United States Patent Publication No. 2003/0128179 (“the '179 application”) [U.S. patent application Ser. No. 10/278,352] entitled “IMPROVEMENTS TO COLOR FLAT PANEL DISPLAY SUB-PIXEL ARRANGEMENTS AND LAYOUTS FOR SUB-PIXEL RENDERING WITH SPLIT BLUE SUB-PIXELS,” filed Oct. 22, 2002; (4) United States Patent Publication No. 2004/0051724 (“the '724 application”) [U.S. patent application Ser. No. 10/243,094] entitled “IMPROVED FOUR COLOR ARRANGEMENTS AND EMITTERS FOR SUB-PIXEL RENDERING,” filed Sep. 13, 2002; (5) United States Patent Publication No. 2003/0117423 (“the '423 application”) [U.S. patent application Ser. No. 10/278,328] entitled “IMPROVEMENTS TO COLOR FLAT PANEL DISPLAY SUB-PIXEL ARRANGEMENTS AND LAYOUTS WITH REDUCED BLUE LUMINANCE WELL VISIBILITY,” filed Oct. 22, 2002; (6) United States Patent Publication No. 2003/0090581 (“the '581 application”) [U.S. patent application Ser. No. 10/278,393] entitled “COLOR DISPLAY HAVING HORIZONTAL SUB-PIXEL ARRANGEMENTS AND LAYOUTS,” filed Oct. 22, 2002; (7) United States Patent Publication No. 2004/0080479 (“the '479 application”) [U.S. patent application Ser. No. 10/347,001] entitled “IMPROVED SUB-PIXEL ARRANGEMENTS FOR STRIPED DISPLAYS AND METHODS AND SYSTEMS FOR SUB-PIXEL RENDERING SAME,” filed Jan. 16, 2003, novel sub-pixel arrangements are therein disclosed for improving the cost/performance curves for image display devices and herein incorporated by reference.


These improvements are particularly pronounced when coupled with sub-pixel rendering (SPR) systems and methods further disclosed in those applications and in commonly owned United States patent applications: (1) United States Patent Publication No. 2003/0034992 (“the '992 application”) [U.S. patent application Ser. No. 10/051,612] entitled “CONVERSION OF A SUB-PIXEL FORMAT DATA TO ANOTHER SUB-PIXEL DATA FORMAT,” filed Jan. 16, 2002, and now issued as U.S. Pat. No. 7,123,277 B2; (2) United States Patent Publication No. 2003/0103058 (“the '058 application”) [U.S. patent application Ser. No. 10/150,355] entitled “METHODS AND SYSTEMS FOR SUB-PIXEL RENDERING WITH GAMMA ADJUSTMENT,” filed May 17, 2002, and now issued as U.S. Pat. No. 7,221,381 B2; (3) United States Patent Publication No. 2003/0085906 (“the '906 application”) [U.S. patent application Ser. No. 10/215,843] entitled “METHODS AND SYSTEMS FOR SUB-PIXEL RENDERING WITH ADAPTIVE FILTERING,” filed Aug. 8, 2002, and now issued as U.S. Pat. No. 7,184,066 B2; (4) United States Patent Publication No. 2004/0196302 (“the '302 application”) [U.S. patent application Ser. No. 10/379,767] entitled “SYSTEMS AND METHODS FOR TEMPORAL SUB-PIXEL RENDERING OF IMAGE DATA” filed Mar. 4, 2003; (5) United States Patent Publication No. 2004/0174380 (“the '380 application”) [U.S. patent application Ser. No. 10/379,765] entitled “SYSTEMS AND METHODS FOR MOTION ADAPTIVE FILTERING,” filed Mar. 4, 2003, and now issued as U.S. Pat. No. 7,167,186 B2; (6) U.S. Pat. No. 6,917,368 (“the '368 patent”) [U.S. patent application Ser. No. 10/379,766] entitled “SUB-PIXEL RENDERING SYSTEM AND METHOD FOR IMPROVED DISPLAY VIEWING ANGLES” filed Mar. 4, 2003, and now issued as U.S. Pat. No. 6,917,368 B2; (7) United States Patent Publication No. 2004/0196297 (“the '297 application”) [U.S. patent application Ser. No. 10/409,413] entitled “IMAGE DATA SET WITH EMBEDDED PRE-SUBPIXEL RENDERED IMAGE” filed Apr. 7, 2003, which are hereby incorporated herein by reference.





BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in, and constitute a part of this specification illustrate exemplary implementations and embodiments of the invention and, together with the description, serve to explain principles of the invention.



FIG. 1A depicts a typical RGB striped panel display having a standard 1×1 dot inversion scheme.



FIG. 1B depicts a typical RGB striped panel display having a standard 1×2 dot



FIG. 2 depicts a novel panel display comprising a subpixel repeat grouping that is of even modulo.



FIGS. 3A and 3B depict the panel display of FIG. 2 with one possible set of crossover connections to provide a dot inversion scheme that may abate some undesirable visual effects.



FIG. 4 shows one possible embodiment of a crossover as implemented.



FIGS. 5A and 5B show one possible array of bonding pads without a crossover and with a crossover respectively.



FIGS. 6A and 6B show yet another possible array of bonding pads without a crossover and with a crossover respectively.



FIG. 7 depicts columns that might be adversely impacted by the effect of crossovers, if no compensation is applied.



FIG. 8 depicts another solution to some undesirable visual effects on a repeat subgrouping of even modulo, with a change in dot inversion at driver chip boundaries.



FIG. 9 shows a prior art four color arrangement for a display using a repeat cell consisting of four subpixels.





DETAILED DESCRIPTION

Reference will now be made in detail to implementations and embodiments, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.



FIG. 1A shows a conventional RGB stripe structure on panel 100 for an Active Matrix Liquid Crystal Display (AMLCD) having thin film transistors (TFTs) 116 to activate individual colored subpixels—red green 106 and blue 108 subpixels respectively. As may be seen, a red, a green and a blue subpixel form a repeating group of subpixels 102 for panel 100.


As also shown, each subpixel is connected to a column line (each driven by a column driver 110) and a row line (e.g. and 114). In the field of AMLCD panels, it is known to drive the panel with a dot inversion scheme to reduce crosstalk and flicker. FIG. 1A depicts one particular dot inversion scheme—i.e. 1×1 dot inversion—that is indicated by a “+” and a “−” polarity given in the center of each subpixel. Each row line is typically connected to a gate (not shown in FIG. 1A) of TFT 116. Image data—delivered via the column lines—are typically connected to the source of each TFT. Image data is written to the panel a row at a time and is given a polarity bias scheme as indicated herein as either ODD (“O”) or EVEN (“E”) schemes. As shown, row 112 is being written with ODD polarity scheme at a given time while row 114 is being written with EVEN polarity scheme at a next time. The polarities alternate ODD and EVEN schemes a row at a time in this 1×1 dot inversion scheme.



FIG. 1B depicts another conventional RGB stripe panel having another dot inversion scheme—i.e. 1×2 dot inversion. Here, the polarity scheme changes over the course of two rows—as opposed to every row, as in 1×1 dot inversion. In both dot inversion schemes, a few observations are noted: (1) in 1×1 dot inversion, every two physically adjacent subpixels (in both the horizontal and vertical direction) are of different polarity; (2) in 1×2 dot inversion, every two physically adjacent subpixels in the horizontal direction are of different polarity; (3) across any given row, each successive colored subpixel has an opposite polarity to its neighbor. Thus, for example, two successive red subpixels along a row will be either (+,−) or (−,+). Of course, in 1×1 dot inversion, two successive red subpixels along a column having opposite polarity; whereas in 1×2 dot inversion, each group of two successive red subpixels will have opposite polarity. This changing of polarity decreases noticeable visual effects that occur with particular images rendered upon an AMLCD panel.



FIG. 2 shows a panel comprising a subpixel repeating group 202, as further described in the '225 application. As may be seen, subpixel repeating group 202 is an eight subpixel repeat group, comprising a checkerboard of red and blue subpixels 104 and 108, respectively, with two columns of reduced-area green subpixels 106 in between. The following discussion may be applied to other subpixel repeating groups, such as a checkerboard of red and green with two columns of reduced area blue subpixels in between, without departing from the scope of the present invention. If the standard 1×1 dot inversion scheme is applied to a panel comprising such a repeating group (as shown in FIG. 2), then it becomes apparent that the property described above for RGB striped panels (namely, that successive colored pixels in a row and/or column have different polarities) is now violated. This condition may cause a number of visual defects noticed on the panel—particularly when certain image patterns are displayed. This observation also occurs with other novel subpixel repeating groups—for example, the subpixel repeating group in FIG. 1 of the '179 application—and other repeating groups that are not an odd number of repeating subpixels across a row. Thus, as the traditional RGB striped panels have three such repeating subpixels in its repeat group (namely, R, G and B), these traditional panels do not necessarily violate the above noted conditions.


Repeating group 202 of FIG. 2 in the present application, however, has four (i.e. an even number of) subpixels in its repeating group across a row (e.g. R, G, B, and G). It will be appreciated that the embodiments described herein are equally applicable to all such even modulus repeat groupings (i.e. 2, 4, 6, 8, etc subpixels across a row and/or column)—including the Bayer repeat pattern and all of its variants as well as several other layouts incorporated by reference from the patent applications listed above. For example, FIG. 9 is a prior art arrangement of four colors, sometimes called the Quad Arrangement, similar to the earlier Bayer pattern, but with one of the green subpixels replaced with a white. The repeat cell 120 consists of four subpixels, each of a different color, often red 104, green 106, blue 108, and white 122.


In the '232 application, now issued as U.S. Pat. No. 6,903,754 B2, there is disclosed various layouts and methods for remapping the TFT backplane so that, although the TFTs of the subpixels may not be regularly positioned with respect to the pixel element itself (e.g. the TFT is not always in the upper left hand corner of the pixel element), a suitable dot inversion scheme may be effected on a panel having an even modulo subpixel repeat grouping. Other possible solutions are possible and disclosed in the co-pending applications noted above.


If it is desired not to re-design the TFT backplane, and if it is also desired to utilize standard column drivers to effect a suitable dot inversion scheme, one possible implementation is to employ crossover connections to the standard column driver lines, as herein described. The first step to a final and suitable implementation is to design a polarity inversion pattern to suit the subpixel repeating group in question. For example, subpixel repeating group of FIG. 2 looks like:




















R
G
B
G



B
G
R
G










with the R and B subpixels on a checkerboard and G subpixels interspersed between. Although FIG. 2 depicts that the green subpixels are of reduced area as compared to the red and blue subpixels themselves, it will be appreciated that all subpixels may be the same size or that other subpixel dimensioning is possible without departing from the scope of the present invention.


So, with the idea of choosing suitable polarity inversion patterns that would minimize flicker and crosstalk, the following are but a few exemplary embodiments disclosed:



















Pattern 1:
R+ G+ B+ G− R− G+ B− G−
[REPEAT]



Pattern 2:
R+ G+ B− G− R− G+ B+ G−
[REPEAT]



Pattern 3:
R+ G− B+ G+ R− G− B− G+
[REPEAT]



Pattern 4:
R+ G− B− G+ R− G− B+ G+
[REPEAT]










First Embodiment of Pattern 1


















(+) 1.
R+ G+ B+ G− R− G+ B− G−
[REPEAT]



(+) 2.
B− G− R− G+ B+ G− R+ G+
[REPEAT]



(−) 3.
R− G− B− G+ R+ G− B+ G+
[REPEAT]



(−) 4.
B+ G+ R+ G− B− G+ R− G−
[REPEAT]










Second Embodiment of Pattern 1


















(+) 1.
R+ G+ B+ G− R− G+ B− G−
[REPEAT]



(+) 2.
B− G− R− G+ B+ G− R+ G+
[REPEAT]



(−) 3.
R− G+ B− G− R+ G+ B+ G−
[REPEAT]



(−) 4.
B+ G− R+ G+ B− G− R− G+
[REPEAT]










Patterns 1 through 4 above exemplify several possible basis patterns upon which several inversion schemes may be realized. A property of each of these patterns is that the polarity applied to each color alternates with each incidence of color.


These and other various polarity inversion patterns can then be implemented upon a panel having subpixel repeating group 202 and Patterns 1-4 as a template. For example, a first embodiment of pattern 1 is shown above. The first row repeats the polarities of pattern 1 above and then, for the second row, the polarities are inverted. Then, as shown above, applying alternating 2 row inversion, alternating polarities of R and B in their own color planes may be realized. And the Gs alternate every second row. The second embodiment of Pattern 1 shown above, however, allows for alternating Gs every row.


It will be appreciated that other basis patterns may be suitable that alternate every two or more incidences of a colored subpixel and still achieve desirable results. It will also be appreciated that the techniques described herein may be used in combination with the techniques of the other co-pending applications noted above. For example, the patterns and crossovers described herein could be applied to a TFT backplane that has some or all of its TFT located in different locations with respect to the pixel element. Additionally, there may be reasons when FINNEGAN designing the driver to alternate less frequently than every incidence (e.g., G less often than R and/or B) in order to reduce driver complexity or cost.


Polarity inversion patterns, such as the ones above, may be implemented at various stages in the system. For example, the driver could be changed to implement the pattern directly. Alternatively, the connections on the panel glass could be rerouted. For example, FIG. 3A is one embodiment of a set of crossover connections that implements Pattern 2 above in a panel 300. Crossovers 302 are added to interchange the column data on columns 2 and 3, 5 and 6, etc. Thus, two crossovers are added in this embodiment per every 8 columns. For a UXGA (1600×1200) panel, this might add approximately 800 crossovers to the column driver set. FIG. 3B depicts how a driver circuit coupled to panel 300 provides image data signals to panel 300 to effect the polarity inversion of Pattern 2 using the set of crossover connections of FIG. 3A. Other patterns may be implemented with different sets of crossovers without departing from the scope of the present invention.


To implement the crossovers, a simple process can be used that utilizes existing processing steps for TFTs. FIG. 4 shows a typical crossover. Driver pads 402 are connected to driver lines 404 which extend down as a column line to intersect with gate lines 408 and send data through TFT 410. Where the drivers are meant to crossover, an insulator layer (406) may be placed so as to prevent shorts and other problems. Driver lines 404 and insulator layer 406 can be fabricated using standard LCD fabrication techniques.


Another embodiment of a crossover is shown in FIGS. 5A and 5B. FIG. 5A shows an array of bonding pads 502. Each pad has a given polarity—the output of which is shown at the bottom of the driver lines 504. For a spacing on the column electrodes of 80 um, the bonding pads shown in FIGS. 5A and 5B are approximately 80 um square with a 80 um space. With such a spacing, it is possible to form crossover 506 as shown in FIG. 5B. As may be seen, this “swap” may be accomplished by rerouting the traces on the glass or the TAB chip carrier as shown.



FIGS. 6A and 6B show yet another embodiment of crossover connections to implement polarity patterns as described above. FIG. 6A depicts the bonding pads 602 as another array of such pads—each pad effecting a polarity on the column lines 604, the polarity of which is shown at the bottom of each such line. FIG. 6B shows how a crossover connection 606 could be effected with such a pad structure. As alternative embodiments, the bonding pads could be for chip on glass COG or for inner lead or outer lead bonds on a tape chip carrier. In such a case, with 80 um column spacing, the bonding pads are now 40 um with 40 um space—i.e. with enough room to route the leads as shown.


One possible drawback to the crossovers is a potential visual effect wherein every crossover location may have a visually darker or lighter column—if this effect is not compensated. FIG. 7 shows one embodiment of a panel 700 having crossovers. On the columns that have crossovers, such as column 702 and other columns as circled, these columns may be slightly darker or lighter than the other columns. This effect is caused by coupling capacitance between the source (data) lines and the pixel electrodes. Normally, each source line is the opposite polarity so the coupling of extraneous voltages is canceled on the pixel electrode. If the source lines are the same polarity, then the pixel voltage will be reduced and the pixel column will appear darker or lighter. This effect is generally independent of the data voltages and can be compensated by a correction signal added to the voltage of the dark or light column. Furthermore, this visual effect can occur when horizontally adjacent pixels have the same polarity. The mechanism for the darkening or lightening is the parasitic capacitance between the data line to the pixel electrode. When the two adjacent data lines, one on the right of the affected pixel and one on the left of the affected pixel, are of opposite polarity, the effect of the parasitic coupling from each data line tends to cancel each other. However, when the polarities of each data line are the same, they will not cancel each other, and there will be a net bias applied to the pixel electrode. This net bias will have the effect or lowering the magnitude of the pixel electrode voltage. For normally black LCD panels, the effect will be to darken the pixel. For normally white LCD panels, the effect will be to lighten the pixel.


This same darker or lighter column effect occurs in another possible solution to the problem of image degradation or shadowing if same colored pixels have the same polarity along a row for an extended area on the screen. FIG. 8 shows a panel 800 having the same subpixel repeating subgrouping as FIG. 2. Standard driver chips 802 and 804 are used to drive the column lines 806—and effecting a 1×2 dot inversion scheme as shown. Although same color subpixels across a row under one such chip (say 802) and might cause some shadowing, this visual effect is somewhat abated by reversing the inversion scheme at the chip boundary 808. It may now be seen that the same colored subpixels under chip 804 will have different polarities as those under chip 802 which abates the shadowing. However, the column at the chip boundary 808 will be darker or lighter than the other columns—unless compensated.


In order to correct or otherwise compensate for the darker or lighter columns that occur as described herein, a predetermined voltage can be added to the data voltage on the darker or lighter columns so as to compensate for the dark or light column. This correction voltage is independent of the data voltage so can be added as a fixed amount to all darker or lighter columns. This correction value can be stored in a ROM incorporated in the driver electronics.


A second compensation method is the look forward compensation method. In this method, each of the data values of the pixels connected to data lines adjacent to the affect pixel are examined for the subsequent frame. From these values, an average compensation value can be calculated and applied to the affected pixel. The compensation value can be derived to a precision suitable to the application. This method requires a frame buffer to store the next frame worth of data. From this stored data, the compensation value would be derived.


A third method is the look back method. Under the assumption that the frame to frame difference in the compensation value is negligible, the data from the previous frame's data may be used to calculate the compensation value for the affected pixel. This method will generally provide a more accurate compensation value than the first method without requiring the frame buffer described in the second method. The third method may have the greatest error under some specific scene changes. By detecting the occurrence of those scene changes, the look back compensation may be turned off, and an alternate method, such as no compensation or either of the compensation methods described above, may be applied for that circumstance.


For the above implementations and embodiments, it is not necessary that crossover connections be placed for every occurrence of a subpixel repeating group. Indeed, while it might be desirable to have no two incidences of a same-colored subpixel having the same polarity, the visual effect and performance of the panel, from a user's standpoint, might be good enough to abate any undesirable visual effects by allowing some two or more incidences of same-colored subpixels (in either a row or column direction) to have the same polarity. Thus, it suffices for the purposes of the present invention that there could be fewer crossover connections to achieve a reasonable abatement of bad effects. Any fewer number of crossover connections could be determined empirically or heuristically, while noting the visual effects thereof, in order to achieve satisfactory performance from a user's standpoint.

Claims
  • 1. A liquid crystal display comprising: a panel comprising a subpixel repeating group, the group having an even number of subpixels in a first direction;a driver circuit coupled to the panel providing image data signals effecting polarity inversion to the panel; anda plurality of crossover column data lines from the driver circuit to subpixels in selected ones of the columns of the panel such that polarities of same color subpixels in the first direction alternate at a spatial frequency sufficient to abate undesirable visual effects on the panel when an image is displayed thereon; each crossover column data line being connected to all subpixels in the column and applying the same polarity to each subpixel in the column at a given time period.
  • 2. The liquid crystal display of claim 1, wherein the first direction is along a row of subpixels of the panel.
  • 3. The liquid crystal display of claim 1, wherein the first direction is along a column of subpixels of the panel.
  • 4. The liquid crystal display of claim 1, wherein the subpixel repeating group comprises an even-numbered sequence of at least two of red (R), green (G), and blue (B) colored subpixels in at least one of a row and column direction.
  • 5. The liquid crystal display of claim 1, wherein the subpixel repeating group comprises a sequence of red (R) green (G) blue (B) green (G) colored subpixels along a row direction.
  • 6. The liquid crystal display of claim 1, wherein the polarity inversion applied to the panel is a 1 column×1 row polarity inversion pattern in which each column data line from the driver circuit to a column of the panel alternates polarity with a preceding or succeeding column data line, and alternating single rows are written with a first polarity pattern at a first given time and with a second polarity pattern at a next time, such that the polarities alternate a row at a time.
  • 7. The liquid crystal display of claim 1, wherein the polarity inversion applied to the panel is 1 column×2 row polarity inversion pattern in which each column data line from the driver circuit to a column of the panel alternates polarity with a preceding or succeeding column data line, and every two alternating rows are written with a first polarity pattern at a first given time and with a second polarity pattern at a next time, such that the polarities alternate two rows at a time.
  • 8. The liquid crystal display of claim 1, wherein the spatial frequency at which said polarities of said same color subpixels in the first direction changes is every two incidences of same colored subpixels.
  • 9. The liquid crystal display of claim 1, wherein the spatial frequency at which said polarities of said same color subpixels in the first direction changes is greater than every two incidences of same colored subpixels.
  • 10. A method for effecting a polarity inversion scheme upon subpixels of a liquid crystal display, the display comprising a subpixel repeating group having an even number of subpixels in a first direction and a driver circuit coupled to the display providing image data signals to the display, the method comprising: assigning a polarity to each subpixel in one or more repeating groups such that same colored subpixels in the first direction alternate polarity at a spatial frequency sufficient to abate undesirable visual effects on the panel when an image is displayed thereon; andproviding crossover column data lines from the driver circuit to subpixels in selected columns of the display to effect the assigned polarities; each crossover column data line being connected to all subpixels in the column and applying the assigned polarity to each subpixel in the column at a given time period.
  • 11. The method of claim 10, wherein the spatial frequency at which said polarities of said same color subpixels in the first direction changes is every two incidences of same colored subpixels.
  • 12. The method of claim 10, wherein the spatial frequency at which said polarities of said same color subpixels in the first direction changes is greater than every two incidences of same colored subpixels.
  • 13. The liquid crystal display of claim 1, wherein the driver circuit selectively adds a predetermined correction voltage to the data voltage on columns of subpixels exhibiting dark or light colors.
  • 14. The liquid crystal display of claim 13, wherein the predetermined correction voltage is a fixed voltage value.
  • 15. The liquid crystal display of claim 1, wherein an average voltage value is selectively added to the data voltage applied to a subpixel affected with an undesirable characteristic; the average voltage value being computed based on voltage values of surrounding subpixels.
  • 16. The liquid crystal display of claim 15, wherein the average voltage value is computed based on previous frame subpixel voltage values.
  • 17. The method of claim 10 for effecting a polarity inversion scheme upon subpixels of a liquid crystal display, wherein the subpixel repeating group comprises a sequence of red (R) green (G) blue (B) green (G) colored subpixels along a row direction.
  • 18. The method of claim 10 for effecting a polarity inversion scheme upon subpixels of a liquid crystal display, wherein the subpixel repeating group comprises an even-numbered sequence of at least two of red (R), green (G), and blue (B) colored subpixels in at least one of a row and column direction.
  • 19. The method of claim 10 for effecting a polarity inversion scheme upon subpixels of a liquid crystal display, wherein the step of assigning a polarity to each subpixel in one or more repeating groups comprises assigning a 1 column×1 row polarity inversion pattern to the display in which each column data line from the driver circuit to a column of the display alternates polarity with a preceding or succeeding column data line, and alternating single rows are written with a first polarity pattern at a first given time and with a second polarity pattern at a next time, such that the polarities alternate a row at a time.
  • 20. The method of claim 10 for effecting a polarity inversion scheme upon subpixels of a liquid crystal display, wherein the step of assigning a polarity to each subpixel in one or more repeating groups comprises assigning a 1 column×2 row polarity inversion pattern to the display in which each column data line from the driver circuit to a column of the display alternates polarity with a preceding or succeeding column data line, and every two alternating rows are written with a first polarity pattern at a first given time and with a second polarity pattern at a next time, such that the polarities alternate two rows at a time.
  • 21. A liquid crystal display comprising: a panel comprising a subpixel repeating group, said subpixel repeating group having an even number of subpixels in a first direction; said subpixels disposed in an array of rows and columns; anda driver circuit coupled to the panel adapted to provide image data signals effecting polarity inversion to the panel; said driver circuit comprising a plurality of column data lines each connected to a respective one of the columns of subpixels such that each column of subpixels is connected to a single column data line; said plurality of column data lines further comprising a plurality of pairs of first and second crossover column data lines connected to first and second columns of subpixels; said second crossover column data line being configured to connect to said first column of subpixels; said first crossover column data line being configured to connect to said second column of subpixels.
  • 22. The liquid crystal display of claim 21, wherein each pair of first and second crossover column data lines comprises adjacent column data lines; wherein said second crossover column data line crosses over said first crossover column data line and connects to said first column of subpixels; and wherein said first crossover column data line crosses over said second crossover column line and connects to a second column of subpixels adjacent to said first column of subpixels.
  • 23. The liquid crystal display of claim 21, wherein each of said first and second crossover column data lines is attached to a bonding pad; and wherein said second crossover column data line is routed around the bonding pad of said first crossover column data line in order to connect to said first column of subpixels.
  • 24. The liquid crystal display of claim 21, wherein said plurality of pairs of first and second crossover column data lines implement a polarity inversion pattern that causes polarities of same color subpixels in the first direction to alternate at a spatial frequency sufficient to abate undesirable visual effects on the panel when an image is displayed thereon.
  • 25. The liquid crystal display of claim 24, wherein the spatial frequency at which the polarities of same color subpixels in the first direction alternate is every two incidences of same colored subpixels.
  • 26. The liquid crystal display of claim 24, wherein the spatial frequency at which the polarities of same color subpixels in the first direction alternate is greater than every two incidences of same colored subpixels.
  • 27. A method for configuring a plurality of column data lines of a driver circuit of a liquid crystal display, the driver circuit coupled to the display and adapted to provide image data signals thereto, the display comprising a panel, the panel comprising a subpixel repeating group having an even number of subpixels in a first direction, said subpixels being disposed in an array of rows and columns, the method comprising: providing a plurality of column data lines from said driver circuit; each column data line being connected to a respective one of the columns of subpixels such that each column of subpixels is connected to a single column data line; andconfiguring the plurality of column data lines to include a plurality of pairs of first and second crossover column data lines connected to first and second columns of subpixels; said second crossover column data line being configured to connect to said first column of subpixels; said first crossover column data line being configured to connect to said second column of subpixels.
  • 28. The method of claim 27, wherein providing said plurality of pairs of first and second crossover column data lines comprises providing a sufficient number of pairs of first and second crossover column data lines to implement a polarity inversion pattern that causes polarities of same color subpixels in the first direction to alternate at a spatial frequency sufficient to abate undesirable visual effects on the panel when an image is displayed thereon.
  • 29. The method of claim 28, wherein providing said plurality of pairs of first and second crossover column data lines comprises providing a sufficient number of pairs of first and second crossover column data lines to implement a polarity inversion pattern that causes polarities of same color subpixels in the first direction to alternate every two incidences of same colored subpixels.
  • 30. The method of claim 28, wherein providing said plurality of pairs of first and second crossover column data lines comprises providing a sufficient number of pairs of first and second crossover column data lines to implement a polarity inversion pattern that causes polarities of same color subpixels in the first direction to alternate more than every two incidences of same colored subpixels.
  • 31. The method of claim 27, wherein configuring the plurality of column data lines to include a plurality of pairs of first and second crossover column data lines comprises configuring said first and second crossover column data lines as adjacent column data lines such that said second crossover column data line crosses over said first crossover column data line in order to connect to said first column of subpixels and said first crossover column data line crosses over said second crossover column line in order to connect to a second column of subpixels adjacent to said first column of subpixels.
  • 32. The method of claim 27, wherein configuring the plurality of column data lines to include a plurality of pairs of first and second crossover column data lines comprises attaching each of said first and second crossover column data lines to a bonding pad, and routing said second crossover column data line around the bonding pad of said first crossover column data line in order to connect to said first column of subpixels.
US Referenced Citations (154)
Number Name Date Kind
3971065 Bayer Jul 1976 A
4353062 Lorteije et al. Oct 1982 A
4642619 Togashi Feb 1987 A
4651148 Takeda et al. Mar 1987 A
4773737 Yokono et al. Sep 1988 A
4781438 Noguchi Nov 1988 A
4800375 Silverstein et al. Jan 1989 A
4822142 Yasui Apr 1989 A
4853592 Strathman Aug 1989 A
4874986 Menn et al. Oct 1989 A
4886343 Johnson Dec 1989 A
4908609 Stroomer Mar 1990 A
4920409 Yamagishi Apr 1990 A
4965565 Noguchi Oct 1990 A
5006840 Hamada et al. Apr 1991 A
5052785 Takimoto et al. Oct 1991 A
5097297 Nakazawa Mar 1992 A
5113274 Takahashi et al. May 1992 A
5144288 Hamada et al. Sep 1992 A
5184114 Brown Feb 1993 A
5191451 Katayama et al. Mar 1993 A
5311205 Hamada et al. May 1994 A
5384266 Chapman Jan 1995 A
5459595 Ishiguro Oct 1995 A
5754163 Kwon May 1998 A
5767829 Verhulst Jun 1998 A
5808594 Tsuboyama et al. Sep 1998 A
5818405 Eglit et al. Oct 1998 A
5818968 Yoshimoto Oct 1998 A
5899550 Masaki May 1999 A
5949396 Lee Sep 1999 A
5971546 Park Oct 1999 A
6069670 Borer May 2000 A
6088050 Ng Jul 2000 A
6097367 Kuriwaki et al. Aug 2000 A
6108122 Ulrich et al. Aug 2000 A
6115092 Greene et al. Sep 2000 A
6144352 Matsuda et al. Nov 2000 A
6147664 Hansen Nov 2000 A
6151001 Anderson et al. Nov 2000 A
6160535 Park Dec 2000 A
6188385 Hill et al. Feb 2001 B1
6219019 Hasegawa Apr 2001 B1
6219025 Hill et al. Apr 2001 B1
6225967 Hebiguchi May 2001 B1
6225973 Hill et al. May 2001 B1
6236390 Hitchcock May 2001 B1
6239783 Hill et al. May 2001 B1
6243055 Fergason Jun 2001 B1
6243070 Hill et al. Jun 2001 B1
6278434 Hill et al. Aug 2001 B1
6326981 Mori et al. Dec 2001 B1
6327008 Fujiyoshi Dec 2001 B1
6332030 Manjunath et al. Dec 2001 B1
6335719 An et al. Jan 2002 B1
6340970 Furuhashi et al. Jan 2002 B1
6340998 Kim et al. Jan 2002 B1
6342876 Kim Jan 2002 B1
6348929 Acharya et al. Feb 2002 B1
6377262 Hitchcock et al. Apr 2002 B1
6388644 De Zwart et al. May 2002 B1
6392717 Kunzman May 2002 B1
6393145 Betrisey et al. May 2002 B2
6396505 Lui et al. May 2002 B1
6469756 Booth, Jr. Oct 2002 B1
6469766 Waterman et al. Oct 2002 B2
6545653 Takahara et al. Apr 2003 B1
6552706 Ikeda et al. Apr 2003 B1
6570584 Cok et al. May 2003 B1
6590555 Su et al. Jul 2003 B2
6624828 Dresevic et al. Sep 2003 B1
6661429 Phan Dec 2003 B1
6674436 Dresevic et al. Jan 2004 B1
6680761 Greene et al. Jan 2004 B1
6714206 Martin et al. Mar 2004 B1
6714212 Tsuboyama et al. Mar 2004 B1
6714243 Mathur et al. Mar 2004 B1
6727878 Okuzono et al. Apr 2004 B2
6738204 Chuang et al. May 2004 B1
6750875 Keely, Jr. et al. Jun 2004 B1
6771028 Winters Aug 2004 B1
6804407 Weldy Oct 2004 B2
6833888 Song et al. Dec 2004 B2
6833890 Hong et al. Dec 2004 B2
6836300 Choo et al. Dec 2004 B2
6850294 Roh et al. Feb 2005 B2
6867549 Cok et al. Mar 2005 B2
6885380 Primerano et al. Apr 2005 B1
6888604 Rho et al. May 2005 B2
6897876 Murdoch et al. May 2005 B2
6903378 Cok Jun 2005 B2
6903754 Elliott Jun 2005 B2
6927754 Lai Aug 2005 B2
6989876 Song et al. Jan 2006 B2
7151518 Fukumoto Dec 2006 B2
7187353 Credelle et al. Mar 2007 B2
7209105 Elliott Apr 2007 B2
7218301 Credelle May 2007 B2
7230667 Shin et al. Jun 2007 B2
20010015716 Kim Aug 2001 A1
20010017607 Kwon et al. Aug 2001 A1
20010052897 Nakano et al. Dec 2001 A1
20020015110 Elliott Feb 2002 A1
20020093476 Hill et al. Jul 2002 A1
20020158997 Fukami et al. Oct 2002 A1
20030006978 Fujiyoshi Jan 2003 A1
20030011603 Koyama et al. Jan 2003 A1
20030071943 Choo et al. Apr 2003 A1
20030077000 Blinn et al. Apr 2003 A1
20030090581 Credelle et al. May 2003 A1
20030146893 Sawabe Aug 2003 A1
20030189537 Yun Oct 2003 A1
20030214499 Ohsawa et al. Nov 2003 A1
20030218618 Phan Nov 2003 A1
20040008208 Dresevic et al. Jan 2004 A1
20040021804 Hong et al. Feb 2004 A1
20040061710 Messing et al. Apr 2004 A1
20040085495 Roh et al. May 2004 A1
20040094766 Lee et al. May 2004 A1
20040095521 Song et al. May 2004 A1
20040104873 Kang et al. Jun 2004 A1
20040108818 Cok et al. Jun 2004 A1
20040114046 Lee et al. Jun 2004 A1
20040150651 Phan Aug 2004 A1
20040155895 Lai Aug 2004 A1
20040169807 Rho et al. Sep 2004 A1
20040174389 Ben-David et al. Sep 2004 A1
20040179160 Rhee et al. Sep 2004 A1
20040189662 Frisken et al. Sep 2004 A1
20040189664 Frisken et al. Sep 2004 A1
20040213449 Safaee-Rad et al. Oct 2004 A1
20040223005 Lee Nov 2004 A1
20040239813 Klompenhouwer Dec 2004 A1
20040239837 Hong et al. Dec 2004 A1
20040246278 Elliott Dec 2004 A1
20040246279 Credelle et al. Dec 2004 A1
20040246280 Credelle et al. Dec 2004 A1
20040246381 Credelle Dec 2004 A1
20040246404 Elliott et al. Dec 2004 A1
20040247070 Ali et al. Dec 2004 A1
20040263528 Murdoch et al. Dec 2004 A1
20050007539 Taguchi et al. Jan 2005 A1
20050024380 Lin et al. Feb 2005 A1
20050040760 Taguchi et al. Feb 2005 A1
20050068477 Shin et al. Mar 2005 A1
20050083277 Credelle Apr 2005 A1
20050083356 Roh et al. Apr 2005 A1
20050099426 Primerano et al. May 2005 A1
20050140634 Takatori Jun 2005 A1
20050151752 Phan Jul 2005 A1
20050162600 Rho et al. Jul 2005 A1
20050212728 Miller et al. Sep 2005 A1
20050219274 Yang et al. Oct 2005 A1
20070146270 Credelle et al. Jun 2007 A1
Foreign Referenced Citations (23)
Number Date Country
0 203 005 Nov 1986 EP
0 322 106 Jun 1989 EP
0 453 033 Oct 1991 EP
1 381 020 Jan 2004 EP
2 146 478 Apr 1985 GB
2 282 928 Apr 1995 GB
60-107022 Jun 1985 JP
06-324649 Nov 1994 JP
08-202317 Aug 1996 JP
11-282008 Oct 1999 JP
2004-004822 Jan 2004 JP
2004 078218 Mar 2004 JP
WO 02099557 Dec 2002 WO
WO 02101644 Dec 2002 WO
WO 03014819 Feb 2003 WO
WO 03050605 Feb 2003 WO
WO 03034380 Apr 2003 WO
WO 03056383 Jul 2003 WO
WO 2004017129 Feb 2004 WO
WO 2004021323 Mar 2004 WO
WO 2004027503 Apr 2004 WO
WO 2004086128 Oct 2004 WO
WO 2005050296 Jun 2005 WO
Related Publications (1)
Number Date Country
20040246213 A1 Dec 2004 US