This application claims priority to Taiwan Application Serial Number 111132267 filed Aug. 26, 2022, which is herein incorporated by reference.
This disclosure is related to a method for driving a display device and display panel that can avoid crosstalk.
In a display panel, crosstalk is generated when the image in one area of the screen affects the brightness of adjacent areas. Crosstalk can be classified into two types: horizontal and vertical. Vertical crosstalk is commonly caused by capacitive coupling between data lines and pixel electrodes, which results in adjacent pixels not accurately displaying gray levels and producing too bright or too dark deviations. When the capacitance between the data lines and the pixel electrodes is too high, high voltage in one area will change the voltage of the pixel electrodes above and below it, causing the color of the top and bottom screens to become brighter or darker. In addition, polarity reversal of the pixels also changes the voltage on the pixel electrodes, which may lead to vertical crosstalk.
Embodiments of the present disclosure provide a display device including the following component. A display panel includes multiple sub-pixels and multiple data lines in which each of the sub-pixels is connected to one of the data lines. A circuit is configured to obtain an image having multiple gray levels corresponding to the sub-pixels respectively. For a first sub-pixel of the sub-pixels, the circuit is configured to obtain a second sub-pixel correspondingly. The circuit is configured to calculate a first compensation value according to the gray level corresponding to the first sub-pixel and the gray level corresponding to the second sub-pixel. The circuit is also configured to calculate a second compensation value according to a polarization state of the first sub-pixel, a polarization state of the second sub-pixel, and a difference between the gray level corresponding to the first sub-pixel and the gray level corresponding to the second sub-pixel. The circuit is configured to calculate a gain according to a position of the first sub-pixel. The circuit is configured to compensate the gray level corresponding to the first sub-pixel according to the first compensation value, the second compensation value, and the gain to obtain an output gray level, and drive the first sub-pixel according to the output gray level.
In some embodiments, the first sub-pixel is located on a first data line of the data lines, and the first data line is adjacent to a second data line and a third data line. In a current frame, a polarization state of the first data line is identical to a polarization state of the second data line, and the polarization state of the first data line is different from a polarization state of the third data line.
In some embodiments, the polarization state of the first data line in the current frame is different from the polarization state of the first data line in a previous frame. The polarization state of the second data line in the current frame is different from the polarization state of the second data line in the previous frame. The polarization state of the third data line in the current frame is different from the polarization state of the third data line in the previous frame.
In some embodiments, the circuit is further configured to input the gray level corresponding to the first sub-pixel and the gray level corresponding to the second sub-pixel into a gray-level lookup table to obtain the first compensation value.
In some embodiments, the first compensation value is positive when the gray level corresponding to the first sub-pixel is greater than the gray level corresponding to the second sub-pixel. The first compensation value is negative when the gray level corresponding to the first sub-pixel is less than the gray level corresponding to the second sub-pixel.
In some embodiments, the circuit is configured to select one of multiple polarization lookup tables according to the polarization state of the first sub-pixel and the polarization state of the second sub-pixel. The circuit is configured to input an absolute difference between the gray level corresponding to the first sub-pixel and the gray level corresponding to the second sub-pixel into the selected polarization lookup table to obtain the second compensation value.
In some embodiments, multiple values in the selected polarization lookup tables are determined based on a concave function of the absolute difference.
In some embodiments, the circuit is configured to input a first coordinate and a second coordinate of the first sub-pixel into a position lookup table to obtain the gain.
In some embodiments, the circuit is configured to multiply the second compensation value with the gain to obtain a product, and add the gray level of the first sub-pixel, the product, and the first compensation value to obtain the output gray level.
From another aspect, embodiments of the present disclosure provide a method for driving a display panel. The method is performed by a circuit. The display panel includes multiple sub-pixels and multiple data lines, and each of the sub-pixels is connected to one of the data lines. The method includes: obtaining an image having multiple gray levels corresponding to the sub-pixels respectively; obtaining a second sub-pixel of the sub-pixels for a first sub-pixel of the sub-pixels; calculating a first compensation value according to the gray level corresponding to the first sub-pixel and the gray level corresponding to the second sub-pixel; calculating a second compensation value according to a polarization state of the first sub-pixel, a polarization state of the second sub-pixel, and a difference between the gray level corresponding to the first sub-pixel and the gray level corresponding to the second sub-pixel; calculating a gain according to a position of the first sub-pixel; and compensating the gray level corresponding to the first sub-pixel according to the first compensation value, the second compensation value, and the gain to obtain an output gray level, and driving the first sub-pixel according to the output gray level.
The invention can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows.
Specific embodiments of the present invention are further described in detail below with reference to the accompanying drawings, however, the embodiments described are not intended to limit the present invention and it is not intended for the description of operation to limit the order of implementation. Moreover, any device with equivalent functions that is produced from a structure formed by a recombination of elements shall fall within the scope of the present invention. Additionally, the drawings are only illustrative and are not drawn to actual size.
The using of “first”, “second”, “third”, etc. in the specification should be understood for identifying units or data described by the same terminology, but are not referred to particular order or sequence.
Referring to
The present disclosure considers the polarization states of the sub-pixels to solve the cross-talk problem, and compensates for the gray levels of the sub-pixels to display the correct brightness. Referring back to
For a currently processed sub-pixel, a corresponding previous sub-pixel is first obtained. For example, in
To illustrate how to compensate for the sub-pixel 201, the sub-pixel 203 is taken as the previous sub-pixel herein. First, a compensation value is calculated based on the gray levels corresponding to the sub-pixel 203 and the sub-pixel 201. When the gray level corresponding to the sub-pixel 201 is greater than the gray level corresponding to the sub-pixel 203, the compensation value is positive. When the gray level corresponding to the sub-pixel 201 is less than the gray level corresponding to the sub-pixel 203, the compensation value is negative. When the gray level corresponding to the sub-pixel 201 is equal to the gray level corresponding to the sub-pixel 203, the compensation value is zero. In some embodiments, the gray levels of the sub-pixel 203 and the sub-pixel 201 are input into the gray-level lookup table 111 to obtain the compensation value represented as LUTgrey(Pre→Cur), where Pre represents the gray level of the sub-pixel 203, Cur represents the gray level of the sub-pixel 201, and LUTgrey( ) represents the gray-level lookup table.
Next, another compensation value is calculated based on the polarization state of the sub-pixel 203, the polarization state of the sub-pixel 201, and a difference between the gray level of sub-pixel 203 and the gray level of sub-pixel 201. Specifically, there are four possible combinations based on the polarization state of the sub-pixel 203 and the polarization state of the sub-pixel 201, which are denoted as “++”, “+−”, “−+”, and “−−”. In this case, four polarization lookup tables are set up, and the corresponding polarization lookup table can be selected based on the polarization state of the sub-pixel 203 and the polarization state of the sub-pixel 201. Next, the absolute difference between the sub-pixel 203's gray level and the sub-pixel 201's gray level is calculated, represented as |Cur−Pre|. This absolute difference is input into the selected polarization lookup table to obtain the second compensation value, denoted as LUTPOL(|Cur−Pre|), where LUTPOL( ) represents the selected polarization lookup table. The polarization lookup table is one-dimensional, and in some embodiments, the values in the polarization lookup table are generated based on a concave function of the absolute difference. For example,
Next, a gain is calculated according to the position of the sub-pixel 201. In some embodiments, the X and Y coordinates of the sub-pixel 201 are input into the position lookup table to obtain the gain.
Finally, an output gray level is obtained by compensating the gray level of the sub-pixel 201 using the calculated compensation values and the gain, as shown in the following Equation 1.
Cur′=Cur+LUTgrey(Pre→Cur)+LUTPOL(|Cur→Pre|)×Gain/256 [Equation 1]
Cur′ is the output gray level. Gain is the aforementioned gain which is divided by “256” in this embodiment, but this division can be integrated into the position lookup table. The second compensation value LUTPOL(|Cur−Pre|) and the gain are multiplied to obtain a product, which is then added to the sub-pixel 201's gray level and the first compensation value LUTgrey(Pre→Cur) to obtain the output gray level. Finally, the sub-pixel 201 is driven based on the output gray level, which can solve the crosstalk problem.
Referring to
In the above-mentioned display device and method, by considering the gray levels, polarization states, and position of the sub-pixel, a better compensation of the gray level can be achieved, thereby solving the problem of vertical crosstalk.
Although the present invention has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein. It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims.
Number | Date | Country | Kind |
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111132267 | Aug 2022 | TW | national |