DISPLAY APPARATUS AND DRIVING METHOD FOR DISPLAY PANEL THEREOF

A display apparatus and a driving method for the display panel thereof are provided. The timing controller of the display apparatus determines whether the frame-displaying signal is a specific frame for displaying a first gray-level value and a second gray-level value. When the frame-displaying signal is corresponding to a specific frame for displaying the first gray-level value and the second gray-level value, the timing controller adjusts a plurality of enabling durations of multiple scan signals to control the pixels displaying the same luminance; when the frame-displaying signal is not corresponding to the specific frame for displaying the first gray-level value and the second gray-level value, the timing controller adjusts the enabling time of the scan signals to be identical to each other.

DESCRIPTION OF THE EMBODIMENTS

FIG. 1is a schematic system diagram of a display apparatus according to an embodiment of the invention. Referring toFIG. 1, in the embodiment, a display apparatus100includes a timing controller110, a source driver120, a scan driver130and a display panel140. The timing controller110receives a frame-displaying signal FDP and is coupled to the source driver120and the scan driver130. The timing controller110provides a display data DDP to the source driver120according to the received frame-displaying signal FDP and provides an output enabling signal OE to the scan driver according to the timing of the received frame-displaying signal FDP. The source driver120receives the display data DDP provided by the timing controller110so as to provide a plurality of pixel voltages VP1-VPn to the display panel140, wherein n is an integer greater. The scan driver130receives the output enabling signal OE provided by the timing controller110so as to provide a plurality of scan signals G1-Gm to the display panel140, wherein m is an integer greater. The scan driver130determines the enabling duration of each of the scan signals G1-Gm according to the output enabling signal OE.

The display panel140includes a plurality of data lines141_1-141—n, a plurality of scan lines143_1-143—m, and a plurality of pixels145and receives a common voltage Vcom. The data lines141_1-141—nare coupled to the source driver120to respectively receive the pixel voltages VP1-VPn, for example, the data line141_1receives the pixel voltage VP1, the data line141_2receives the pixel voltage VP2, and the rest can be deduced by analogy. The scan lines143_1-143—mare coupled to the scan driver130to respectively receive the scan signals G1-Gm, for example, the scan line143_1receives the scan signal G1, the scan line143_2receives the scan signal G2, and the rest can be deduced by analogy.

The pixels145are arranged in an array and respectively coupled to the corresponding data line (for example,141_1-141—n) and the corresponding scan line (for example,143_1-143—m) so as to receive the corresponding pixel voltage (for example, VP1-VPn) and the corresponding scan signal (for example, G1-Gm), in which the data line (for example,141_1-141—n) coupled to each pixel145is different from the data lines (for example,141_1-141—n) coupled to the adjacent pixels145. In other words, each data line (for example,141_1-141—n) and the coupled pixels145are shown in z-shape structure, i.e., the data line (for example,141_1-141—n) coupled to each pixel145is different from the data lines (for example,141_1-141—n) coupled to the horizontally adjacent pixels145and different from the data line (for example,141_1-141—n) coupled to the vertically adjacent pixels145. The horizontal and the vertical terms herein are based on the figures, which the invention is not limited to. The pixels145within a display region ADP give displaying by using the corresponding frame-displaying signal FDP, while the pixels145out of the display region ADP do not have displaying effect and are hidden from the user, i.e., the pixels145out of the display region ADP do not contribute the displaying effect of the display apparatus100so that their displaying effect can be ignored.

In the embodiment, the timing controller110can determine whether the frame-displaying signal FDP divides the pixels145on the display panel140into a plurality of groups for respectively displaying the first gray-level value and the second gray-level value, in which the first gray-level value and the second gray-level value are, for example, the maximum gray-level value and the minimum gray-level value. In terms of a gray-level value range 0-255, the maximum gray-level value can be one of the gray-level values 224-255 and the minimum gray-level value can be one of the gray-level values range 0-31.

When the timing controller110determines out the frame-displaying signal FDP does not divide the pixels145on the display panel140into a plurality of groups for respectively displaying the first gray-level value and the second gray-level value, the scan driver130, controlled by the output enabling signal OE provided by the timing controller110, sets the enabling durations of the scan signals G1-Gm as the identical durations to each other; when the timing controller110determines out the frame-displaying signal FDP divides the pixels145on the display panel140into a plurality of groups for respectively displaying the first gray-level value and the second gray-level value (i.e., the display panel140displays a certain specific frame), the scan driver130, controlled by the output enabling signal OE provided by the timing controller110, adjusts the enabling durations of the scan signals G1-Gm so as to make the pixels145of each group display a same luminance by control. The each group herein includes at least two pixels145. In this way, when the frame-displaying signal FDP divides the pixels145on the display panel140into a plurality of groups for respectively displaying the first gray-level value and the second gray-level value, the probability to produce bright lines and dim lines with the display panel140can be reduced or eliminated.

FIG. 2Ais a frame diagram transmitted by a frame-displaying signal according to an embodiment of the invention andFIG. 2Bis a driving waveform diagram of a display apparatus according to an embodiment of the invention. Referring toFIGS. 1,2A and2B, in the embodiment, the pixels145of the display panel140are divided into a plurality of groups210and220, in which each of the groups210and220includes one column of pixels145, where, i.e., one column of pixels comprises a group210or220; and assuming the pixels145of the group210display the minimum gray-level value GL, the pixels145of the group220display the maximum gray-level value GH and the groups210and220are alternately disposed along the horizontal direction shown by the figure.

In other words, in the embodiment, the groups210and220respectively include identical quantity and identical arrangement of the pixels145; every group210is adjacent to groups220, rather than to groups210; every group220is adjacent to groups210, rather than to groups220. The difference between the minimum gray-level value GL and the common voltage Vcom herein is assumed to be the minimum, and the difference between the maximum gray-level value GH and the common voltage Vcom herein is assumed to be the maximum. The above-mentioned assumption is an example for description convenience, which the embodiment of the invention is not limited to.

In the embodiment, the source driver120takes a column inversion mode to output the pixel voltages VP1-VPn, i.e., the polarity of each pixel voltage (for example, VP1-VPn) is different from the polarity of the adjacent pixel voltages (for example, VP1-VPn), for example, the polarity of the pixel voltage VP2 is different from the polarities of the pixel voltages VP1 and VP3, and the rest can be deduced by analogy, wherein the polarity of the pixel voltage (for example, VP1-VPn) is determined out based on the common voltage Vcom.

Since the data lines141_1-141—nand the pixels145of the display panel140are coupled to each other shown in z-shape structure, the displaying effect of the display panel140is the same as the effect in dot inversion driving mode, and at the time, the pixel voltages VP2-VPn−1 are ceaselessly alternated between the maximum gray-level value GH and the minimum gray-level value GL. When the plurality of durations (for example, P1-P5) for the output enabling signal OE to be low voltage level are the same as each other, the plurality of enabling durations (for example, EP1-EP5) of all the scan signals (for example, G1-G5) are the same as each other. Since the enabling durations (for example, EP1-EP5) of all the scan signals (for example, G1-G5) decide the charging time of the pixels145in the corresponding horizontal scanning durations, the same enabling durations (for example, EP1-EP5) of the scan signals (for example, G1-G5) means the charging time of the pixel145in every horizontal scanning duration is the identical to each other, in which the pixel voltages VP2-VPn−1 are ceaselessly alternated between the maximum gray-level value GH or the minimum gray-level value GL whenever switching the horizontal scanning duration from one to the next.

As shown byFIG. 2B, the pixel voltages VP2-VPn−1 keep the same voltage level (i.e., the DC level) in the enabling duration EP1 of the scan signal G1(i.e., the charging duration of the first horizontal scanning duration), while the voltage levels of the pixel voltages VP2-VPn−1 in the enabling durations (for example, EP2-EP5) of other scan signals (for example, G2-G5) include partial transient voltages (for example, as shown by VT1). When the charging time of every horizontal scanning duration is the identical to each other, the maximum gray-level value GH of the pixel145coupled to the scan line143_1is higher than the maximum gray-level value GH of the pixel145coupled to other scan lines (for example,143_2-143—m). At the time, the maximum gray-level values GH of the pixels145of every group220may be different from each other (i.e., the charging effects of the pixels145are different from each other or the cross-voltages at the two terminals of the pixels145are different from each other), which affects the displaying effect.

According to the description above, the embodiment take such a scheme of lowering down the luminance displayed by the pixel145coupled to the scan line143_1corresponding to the maximum gray-level value GH; at the time, the timing controller110would shorten the duration P1 for low voltage level in the output enabling signal OE corresponding to the enabling duration EP1 of the scan signal G1(i.e., corresponding to the first horizontal scanning duration in a frame duration). In other words, when the timing controller110determines out the frame-displaying signal FDP takes a column of pixels as a group (for example, 210 or 220) for respectively displaying maximum gray-level value GH and the minimum gray-level value GL, the timing controller110shortens the enabling duration EP1 of the scan signal G1 corresponding to the first scanning duration so that the pixels145of each group (for example, 210 or 220) display the same luminance.

In other embodiments, it can increase up the luminance of the pixels coupled to the scan lines143_2-143—mcorresponding to the maximum gray-level value GH; at the time, the timing controller110elongates the durations (for example, P2-P5) for low voltage level in the output enabling signal OE not corresponding to the enabling duration EP1 of the scan signal G1. In other words, when determining the frame-displaying signal FDP takes a column of pixels as a group (for example, 210 or 220) for respectively displaying the maximum gray-level value GH and the minimum gray-level value GL, and the voltage levels of the pixel voltages VP2-VPn−1 in a horizontal scanning duration are different from the voltage levels of the pixel voltages VP2-VPn−1 in the previous horizontal scanning duration, the timing controller110elongates the enabling duration (for example, EP2-EP5) of the scan signal (for example, scan signals G2-G5) corresponding to the present horizontal scanning duration so that the pixels145of each group (for example, 210 or 220) display the same luminance.

The shortened or elongated time length of the durations P1-P5 for low voltage level of the output enabling signal OE depends on the luminance difference of the pixels145of each group (for example, 210 or 220); or the timing controller110can gradually shorten the enabling duration EP1 of the scan signal G1 corresponding to the first enabling duration and/or gradually elongate the enabling durations (for example, EP2-EP5) of the scan signal (for example, G2-G5) not corresponding to the first enabling duration until the pixels145of each group (for example, 210 or 220) display the same luminance.

FIG. 3Ais a frame diagram transmitted by a frame-displaying signal according to another embodiment of the invention andFIG. 3Bis a driving waveform diagram of a display apparatus according to another embodiment of the invention. Referring toFIGS. 1,2A,2B,3A and3B, in the embodiment, the pixels145of the display panel140are divided into a plurality of groups310and320, in which each of the groups310and320includes two pixels145of the same column, i.e., two pixels145of the same column serve as a group310or320. Assuming the pixels145of the group310display the minimum gray-level value GL, the pixels145of the group320display the maximum gray-level value GH, and the groups310and320are disposed in chessboard shape.

In other words, in the embodiment, the groups310and320respectively include identical quantity and identical arrangement of the pixels145; every group310is adjacent to groups320, rather than to groups310; every group320is adjacent to groups310, rather than to groups320. The source driver120takes a column inversion mode to output the pixel voltages VP1-VPn, in which the setting of the minimum gray-level value GL and the maximum gray-level value GH of the pixel voltages VP1-VPn is the same as the above-mentioned embodiment, which is omitted to describe. The pixel voltages VP2-VPn−1 alternately switch the voltage level thereof to be the maximum gray-level value GH or the minimum gray-level value GL every two horizontal scanning durations after the first horizontal scanning duration.

As shown byFIG. 3B, the pixel voltages VP2-VPn−1 keep the same voltage level (i.e., the DC level) in the enabling durations EP1, EP3 and EP5 of the scan signals G1, G3 and G5(i.e., the charging durations of the first, the third and the fifth horizontal scanning duration), while the voltage levels of the pixel voltages VP2-VPn−1 in the enabling durations (for example, EP2 and EP4, i.e., the charging time of other horizontal scanning durations) of other scan signals (for example, G2 and G4) include partial transient voltages (for example, as shown by VT2). When the charging time of every horizontal scanning duration is the identical to each other, the maximum gray-level value GH of the pixel145coupled to the odd scan lines (for example,143_1,143_3and so on) is higher than the maximum gray-level value GH of the pixel145coupled to other even scan lines (for example,143_2,143_4and so on). At the time, the maximum gray-level values GH of the pixels145of every group320may be the different from each other to affect the displaying effect.

According to the description above, the embodiment take such a scheme of lowering down the luminance displayed by the pixel145coupled to the odd (for example,143_1,143_3and so on) corresponding to the maximum gray-level value GH; at the time, the timing controller110would shorten the duration (for example, P1, P3 and so on) for low voltage level in the output enabling signal OE corresponding to the enabling durations (for example, EP1, EP3 and so on) of the odd scan signals (for example, G1, G3 and so on). In other words, when the timing controller110determines out the frame-displaying signal FDP takes the two pixels of a same column as a group (for example, 310 or 320) for respectively displaying maximum gray-level value GH and the minimum gray-level value GL, and the voltage levels of the pixel voltages VP2-VPn−1 in a horizontal scanning duration are the same as the voltage levels of the pixel voltages VP2-VPn−1 in the previous horizontal scanning duration or the horizontal scanning duration is the first horizontal scanning duration of the frame duration, the timing controller110shortens the enabling durations (for example, EP1, EP3 and EP5) of the scan signals (for example, G1, G3 and G5) corresponding to the horizontal scanning duration so that the pixels145of each group (for example, 310 or 320) display the same luminance.

In other embodiments, the timing controller110can increase up the luminance of the pixels coupled to the even scan lines (for example,143_2,143_4and so on) corresponding to the maximum gray-level value GH; at the time, the timing controller110elongates the durations (for example, P2, P4 and so on) for low voltage level in the output enabling signal OE corresponding to the enabling durations (for example, EP2, EP4 and so on) of the even scan signals (for example, G2, G4 and so on). In other words, when the timing controller110determines out the frame-displaying signal FDP takes two pixels of a same column as a group (for example, 310 or 320) for respectively displaying the maximum gray-level value GH and the minimum gray-level value GL, and the voltage levels of the pixel voltages VP2-VPn−1 in a horizontal scanning duration are different from the voltage levels of the pixel voltages VP2-VPn−1 in the previous horizontal scanning duration, the timing controller110elongates the enabling duration (for example, EP2 and EP4) of the scan signals (for example, scan signals G2 and G4) corresponding to the present horizontal scanning duration so that the pixels145of each group (for example, 310 or 320) display the same luminance.

The shortened or elongated length of the durations of low voltage level P1-P5 of the output enabling signal OE depends on the luminance difference of the pixels145of each group (for example, 310 or 320); or the timing controller110can gradually shorten the enabling durations (for example, EP1, EP3 and so on) of the scan signals (for example, G1, G3 and so on) corresponding to the odd horizontal scanning durations and/or gradually elongate the enabling durations (for example, EP2, EP4 and so on) of the scan signals (for example, G2, G4 and so on) corresponding to the even horizontal scanning durations until the pixels145of each group (for example, 310 or 320) display the same luminance.

In some embodiments, the frame-displaying signal FDP may take the three or more pixels of a same column as a group for respectively displaying maximum gray-level value GH and the minimum gray-level value GL. According to the description of the above-mentioned embodiments, when the frame-displaying signal FDP takes the three pixels of a same column as a group for respectively displaying maximum gray-level value GH and the minimum gray-level value GL, the timing controller110can shorten the enabling durations (for example, EP1, EP4 and so on) of the scan signals (for example, G1, G4 and so on) corresponding to the (3i+1)-th horizontal scanning duration and/or gradually elongate the enabling durations (for example, EP2, EP3, EP5 and so on) of the scan signals (for example, G2, G3, G5 and so on) not corresponding to the (3i+1)-th horizontal scanning duration so that the pixels145of each group display the same luminance, wherein i is an integer greater than or equal to 0. The other embodiments of the invention can refer to above-mentioned embodiments to get deduction, which is omitted to describe.

FIG. 4is a flowchart of the driving method for a display panel according to an embodiment of the invention. Referring toFIG. 4, the embodiment is suitable for the display panel140inFIG. 1. The driving method for a display panel includes following steps: receiving a frame-displaying signal (step S410), and determining whether the frame-displaying signal divides the pixels into a plurality of groups to respectively display a first gray-level value and a second gray-level value by a timing controller of a display apparatus (step S410); when the timing controller determines out the frame-displaying signal divides the pixels into a plurality of groups for respectively displaying a first gray-level value and a second gray-level value, i.e., the determining result of step S420is “YES”, adjusting a plurality of enabling durations of the scan signals by the timing controller so as to control the pixels of each of the groups displaying the same luminance (step S430), wherein each of the groups comprises at least two of the pixels.

When the timing controller determines out the frame-displaying signal does not divide the pixels into a plurality of groups for respectively displaying a first gray-level value and a second gray-level value, i.e., the determining result of step S420is “NO”, the timing controller adjusts the enabling durations of the scan signals identical to each other by the timing controller (step S440). The sequence of the above-mentioned steps herein are an example only, which the invention is not limited to. The details of the above-mentioned steps can refer to the embodiments ofFIGS. 1,2A,2B,3A and3B, which are omitted to describe.

In summary, in the display apparatus and the driving method for a display panel thereof in the embodiments of the invention, the timing controller can determine whether the frame-displaying signal is displaying a specific frame, and accordingly, can thereby decide whether needing to adjust the enabling durations of the scan signals to eliminate the luminance differences displayed by the pixels. As a result, the invention can eliminate the bright lines and dim lines caused by a specific frame displayed by the display panel of a display apparatus so as to improve the displaying quality of the display apparatus.