TWI770704B - Polarity compensation device and method - Google Patents

Abstract

A polarity compensation device and a polarity compensation method are provided. The polarity compensation device includes a variance calculation circuit and a compensation calculation circuit. The variance calculation circuit calculates the difference value between current sub-pixel data and previous sub-pixel data in the same frame period, wherein the current sub-pixel data and the previous sub-pixel data belong to the same data line of a display panel. The compensation calculation circuit converts the difference value into a function value. The compensation calculation circuit decides to increase or decrease the current sub-pixel data by the function value according to a polarity corresponding to the same frame period, so as to generate a compensated sub-pixel data.

Description

Polarity compensation device and method

The present invention relates to a display device, and more particularly, to a polarity compensation device and method.

In order to prevent the properties of liquid crystal molecules from being destroyed, the source driver drives the display panel in a polarity inversion manner. In the case of a short charging time, the display panel may experience line sticking. For example, when a large-sized and high-resolution display panel displays a checkerboard test pattern, a line afterimage may appear at the intersection between the black squares and the white squares. One of the reasons for the line afterimage is that the sub-pixel circuit of the display panel has a weak charging capability in a positive polarity, while the sub-pixel circuit has a strong charging capability in a negative polarity. Of course, the charging capability of the sub-pixel circuit in the positive polarity is relatively strong, while the charging capability of the sub-pixel circuit in the negative polarity is relatively weak, and in such a case, a line afterimage may also occur.

FIG. 1 is a schematic diagram of a circuit block of a sub-pixel circuit SPU of a conventional display panel 100 . The display panel 100 shown in FIG. 1 includes a plurality of data lines (or source lines, such as the data lines SL shown in FIG. 1 ), a plurality of scan lines (or gate lines, such as the scan lines GL shown in FIG. 1 ), and A plurality of sub-pixel circuits (eg, the sub-pixel circuit SPU shown in FIG. 1 ). The sub-pixel circuit SPU includes a thin film transistor (TFT) SW1 and other elements (not shown). When the scan line GL turns on the thin film transistor SW1, the driving voltage of the data line SL can be charged to the sub-pixel circuit SPU through the thin film transistor SW1.

However, the gate-to-source (Vgs) voltage of TFT SW1 in positive polarity may be different from the gate-to-source voltage of TFT SW1 in negative polarity. The positive polarity means that the driving voltage Vs of the data line SL is greater than the common voltage Vcom. The negative polarity means that the driving voltage Vs of the data line SL is lower than the common voltage Vcom. Here, it is assumed that the common voltage Vcom is 10 volts, which means that the driving voltage of the “gray scale 255” is 18 volts and 2 volts in the positive and negative polarities, respectively. It is also assumed that the scan voltage Vg of the scan line GL is 28 volts when the scan line GL is scanned. Therefore, the gate-source voltage of TFT SW1 in positive polarity is Vg-Vs = 28-18 = 10 volts, and the gate-source voltage of TFT SW1 in negative polarity is Vg-Vs = 28-2 = 26 volts. In general, the greater the gate-source voltage of a transistor, the greater the current flowing through this transistor. Obviously, the charging capability of the sub-pixel circuit SPU is weaker in positive polarity, while the charging capability of the sub-pixel circuit SPU is stronger in negative polarity. The charging capability in the positive polarity does not match the charging capability in the negative polarity, and such a situation may lead to the occurrence of line afterimages.

It should be noted that the content of the "prior art" paragraph is used to help understand the present invention. Some (or all) of the content (or all of the content) disclosed in the "prior art" paragraph may not be known by those of ordinary skill in the art. The content disclosed in the "Prior Art" paragraph does not mean that the content has been known to those with ordinary knowledge in the technical field before the application of the present invention.

The present invention provides a polarity compensation device and a polarity compensation method to eliminate line afterimages as much as possible.

In an embodiment of the present invention, the above-mentioned polarity compensation device includes a change calculation circuit and a compensation calculation circuit. The variation calculation circuit is configured to calculate the difference between the current sub-pixel data and the previous sub-pixel data in the same frame period, wherein the current sub-pixel data and the previous sub-pixel data belong to a same data line of the display panel. The compensation calculation circuit is coupled to the variation calculation circuit to receive the difference value. The compensation calculation circuit is configured to convert the difference value into a function value. The compensation calculation circuit determines to increase or decrease the function value of the current sub-pixel data according to the polarity corresponding to the same frame period to generate compensated sub-pixel data.

In an embodiment of the present invention, the above-mentioned polarity compensation method includes: calculating a difference value between the current sub-pixel data and the previous sub-pixel data in the same frame period, wherein the current sub-pixel data and the previous sub-pixel data are calculated by the variation calculation circuit. A same data line belonging to the display panel; the difference value is converted into a function value by the compensation calculation circuit; and the current sub-pixel data is determined by the compensation calculation circuit to increase or decrease the function value according to the polarity corresponding to the same frame period, so as to Compensated sub-pixel data is generated.

Based on the above, the polarity compensation device and the polarity compensation method according to the embodiments of the present invention can calculate the difference value between the current sub-pixel data and the previous sub-pixel data of the same data line. According to the difference value and polarity, the compensation calculation circuit can increase or decrease the current sub-pixel data to generate compensated sub-pixel data. Therefore, the polarity compensation device can eliminate line afterimages as much as possible.

In order to make the above-mentioned features and advantages of the present invention more obvious and easy to understand, the following embodiments are given and described in detail with the accompanying drawings as follows.

The term "coupled (or connected)" as used throughout this specification (including the scope of the application) may refer to any direct or indirect means of connection. For example, if it is described in the text that a first device is coupled (or connected) to a second device, it should be interpreted that the first device can be directly connected to the second device, or the first device can be connected to the second device through another device or some other device. indirectly connected to the second device by a connecting means. Terms such as "first" and "second" mentioned in the full text of the description (including the scope of the patent application) in this case are used to designate the names of elements or to distinguish different embodiments or scopes, rather than to limit the number of elements The upper or lower limit of , nor is it intended to limit the order of the elements. Also, where possible, elements/components/steps using the same reference numerals in the drawings and embodiments represent the same or similar parts. Elements/components/steps that use the same reference numerals or use the same terminology in different embodiments may refer to relative descriptions of each other.

FIG. 2 is a schematic diagram of a circuit block of a display device according to an embodiment of the present invention. The display device shown in FIG. 2 includes a pre-processing circuit 10 , a polarity compensation device 300 and a post-processing circuit 20 . According to design requirements, the pre-processing circuit 10 , the polarity compensation device 300 and the post-processing circuit 20 may be integrated into a timing controller. The pre-processing circuit 10 can process the sub-pixel data Din to generate the current sub-pixel data Cur1 for the polarity compensation device 300 . For example, the pre-processing circuit 10 can perform De-Mura, over-driving (OD) and/or other image processing on the sub-pixel data Din.

The polarity compensation device 300 is coupled to the pre-processing circuit 10 to receive the current sub-pixel data Cur1. The polarity compensation device 300 can calculate the difference between the current sub-pixel data Cur1 and the previous sub-pixel data of the same data line. According to the difference value and the polarity, the polarity compensation device 300 can increase or decrease the current sub-pixel data Cur1 to generate the compensated sub-pixel data Cur2. The polarity compensation device 300 can eliminate line afterimages as much as possible.

The post-processing circuit 20 is coupled to the polarity compensation device 300 to receive the compensated sub-pixel data Cur2. The post-processing circuit 20 may process the compensated sub-pixel data Cur2 to generate the sub-pixel data Dout for the source driver (not shown). For example, the post-processing circuit 20 may perform dynamic gamma control (DGC), overdrive (OD), dithering, and/or other image processing on the compensated sub-pixel data Cur2.

FIG. 3 is a circuit block diagram illustrating the polarity compensation device 300 shown in FIG. 2 according to an embodiment of the present invention. In the embodiment shown in FIG. 3 , the polarity compensation device 300 includes a buffer 310 , a variation calculation circuit 320 and a compensation calculation circuit 330 . During a same frame period, the buffer 310 can temporarily store the current sub-pixel data Cur1 and provide the previous sub-pixel data Pre to the change calculation circuit 320 . The current sub-pixel data Cur1 and the previous sub-pixel data Pre belong to the same data line of the display panel (not shown).

FIG. 4 is a schematic flowchart of a polarity compensation method according to an embodiment of the present invention. Please refer to FIG. 3 and FIG. 4 . In step S410, the variation calculation circuit 320 may calculate the difference value DV between the current sub-pixel data Cur1 and the previous sub-pixel data Pre in a same frame period. For example, the difference value DV may be |Cur1-Pre|. The compensation calculation circuit 330 is coupled to the variation calculation circuit 320 to receive the difference value DV. In step S420, the compensation calculation circuit 330 may convert the difference value DV into a function value FV. For example, in some embodiments, the compensation calculation circuit 330 may use the difference value DV to look up one or more lookup tables set according to design requirements, so as to obtain the function value FV. In other embodiments, the compensation calculation circuit 330 may substitute the difference value DV into one or more equations defined according to design requirements, so as to calculate the function value FV.

For example, in some embodiments, the compensation calculation circuit 330 may use the following equation 1 in step S420 to convert the difference value DV into the function value FV. In Equation 1, the difference value DV may be Cur1-Pre, and GLmax represents the grayscale resolution. Taking "8-bit sub-pixel data" as an example, the grayscale resolution GLmax is 2 ⁸ =256. FV = |DV|*|DV|/GLmax Equation 1

In other embodiments, the compensation calculation circuit 330 may use the following equation 2 in step S420 to convert the difference value DV into the function value FV. In Equation 2, the difference value DV may be Cur1-Pre, GLmax represents the grayscale resolution, and W represents the weight value. The weight value W can be a fixed constant determined according to design requirements. Alternatively, the weight value W may be a dynamic value determined according to design requirements. For example, the compensation calculation circuit 330 can compare the current sub-pixel data Cur1 with the previous sub-pixel data Pre to obtain a change relationship. The changing relationship includes “the current sub-pixel data Cur1 is greater than the previous sub-pixel data Pre” or “the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre”. The compensation calculation circuit 330 can know the polarity POL corresponding to the current frame period. The compensation calculation circuit 330 can dynamically adjust the weight value W according to the relationship between the polarity POL and the variation. FV = (|DV|*|DV|/GLmax)*W Equation 2

In still other embodiments, the compensation calculation circuit 330 may use the following equation 3 in step S420 to convert the difference value DV into the function value FV. In Equation 3, the difference value DV may be Cur1-Pre, GLmax represents the grayscale resolution, and W represents the weight value. The lookup value LT in Equation 3 may be a lookup value obtained from the lookup table in accordance with the difference value DV. FV = (|DV|*|LT|/GLmax)*W Equation 3

The look-up table can be defined according to design requirements. For example, in some embodiments, the lookup value LT in Equation 3 may be a lookup value obtained from Table 1 below in accordance with the difference value DV. Table 1: An example of a lookup table DV 0 … 16 … 254 255 LT 0 … 8 … 240 256

In step S430 , according to the polarity corresponding to the same frame period, the compensation calculation circuit 330 may decide to increase or decrease the function value FV of the current sub-pixel data Cur1 to generate the compensated sub-pixel data Cur2 . For example, for some display panels, the gate-to-source (Vgs) voltage of a thin film transistor (TFT) in positive polarity may be lower than the gate-to-source voltage of the thin film transistor (TFT) in negative polarity. Generally speaking, the greater the gate-source voltage of a transistor, the greater the current flowing through this transistor (the stronger the charging capacity). Therefore, in the case where the polarity POL is expressed as "positive polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the compensation calculation circuit 330 can increase the current sub-pixel data Cur1 by the function value FV, so as to Compensated sub-pixel data Cur2 is generated (ie, Cur2 = Cur1 + FV). In the case where the polarity POL is indicated as "positive polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the compensation calculation circuit 330 can reduce the current sub-pixel data Cur1 by the function value FV to generate compensated sub-pixel data Cur2 (ie Cur2 = Cur1 - FV). In the case where the polarity POL is expressed as "negative polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the compensation calculation circuit 330 can reduce the current sub-pixel data Cur1 by the function value FV to generate the Compensate sub-pixel data Cur2 (ie Cur2 = Cur1 - FV). In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the compensation calculation circuit 330 can increase the function value FV to the current sub-pixel data Cur1 to generate compensated sub-pixel data Cur2 (ie, Cur2 = Cur1 + FV).

For other display panels, the gate-to-source (Vgs) voltage of the thin-film transistor (TFT) in positive polarity may be greater than the gate-to-source voltage of the TFT in negative polarity. Therefore, when the polarity POL is expressed as "positive polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the compensation calculation circuit 330 can reduce the current sub-pixel data Cur1 by the function value FV to Compensated sub-pixel data Cur2 is generated (ie, Cur2 = Cur1 - FV). In the case where the polarity POL is indicated as "positive polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the compensation calculation circuit 330 can increase the function value FV to the current sub-pixel data Cur1 to generate compensated sub-pixel data Cur2 (ie, Cur2 = Cur1 + FV). In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the compensation calculation circuit 330 can increase the current sub-pixel data Cur1 by the function value FV to generate the Compensate sub-pixel data Cur2 (ie, Cur2 = Cur1 + FV). In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the compensation calculation circuit 330 can reduce the current sub-pixel data Cur1 by the function value FV to generate compensated sub-pixel data Cur2 (ie Cur2 = Cur1 - FV).

FIG. 5 is a circuit block diagram illustrating the compensation calculation circuit 330 shown in FIG. 3 according to an embodiment of the present invention. In the embodiment shown in FIG. 5 , the compensation calculation circuit 330 includes a function calculation circuit 331 , a subtraction circuit 332 , an addition circuit 333 , a selection circuit 334 and a judgment circuit 335 . The function calculation circuit 331 is coupled to the variation calculation circuit 320 to receive the difference value DV. The function calculation circuit 331 may convert the difference value DV into the function value FV. For example, in some embodiments, the function calculation circuit 331 may use the difference value DV to look up one or more look-up tables set according to design requirements to obtain the function value FV. In other embodiments, the function calculation circuit 331 may substitute the difference value DV into one or more equations (eg, the above-mentioned Equation 1, Equation 2 or Equation 3) defined according to design requirements, so as to calculate the function value FV.

The subtraction circuit 332 and the addition circuit 333 are coupled to the function calculation circuit 331 to receive the function value FV. The subtraction circuit 332 can subtract the current sub-pixel data Cur1 by the function value FV to generate the subtraction result Cur1-FV. The addition circuit 333 is coupled to the function calculation circuit 331 to receive the function value FV. The addition circuit 333 can add the function value FV to the current sub-pixel data Cur1 to generate the addition result Cur1+FV. The selection circuit 334 is coupled to the subtraction circuit 332 and the addition circuit 333 . The selection circuit 334 can dynamically select one of the subtraction result Cur1-FV and the addition result Cur1+FV as the compensated sub-pixel data Cur2.

The determination circuit 335 may control the selection circuit 334 . The determination circuit 335 can also compare the current sub-pixel data Cur1 with the previous sub-pixel data Pre, and check the polarity POL corresponding to the current frame period. For some display panels, the gate-to-source (Vgs) voltage of the thin film transistor (TFT) in positive polarity may be smaller than the gate-to-source voltage of the TFT in negative polarity. Therefore, in the case where the polarity POL is expressed as "positive polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the addition result Cur1+FV as the Compensation sub-pixel data Cur2. In the case where the polarity POL is indicated as "positive polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the subtraction results Cur1-FV as the compensated sub-pixel data Cur2. In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the subtraction result Cur1-FV as the compensated sub-pixel Pixel data Cur2. In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the addition result Cur1+FV as the compensated sub-pixel data Cur2.

For other display panels, the gate-to-source (Vgs) voltage of the thin-film transistor (TFT) in positive polarity may be greater than the gate-to-source voltage of the TFT in negative polarity. Therefore, in the case where the polarity POL is expressed as "positive polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the subtraction result Cur1-FV as the processed sub-pixel data Cur1-FV. Compensation sub-pixel data Cur2. In the case where the polarity POL is indicated as "positive polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the addition result Cur1+FV as the compensated sub-pixel data Cur2. In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the addition result Cur1+FV as the compensated sub-pixel Pixel data Cur2. In the case where the polarity POL is indicated as "negative polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the determination circuit 335 can control the selection circuit 334 to select the subtraction results Cur1-FV as the compensated sub-pixel data Cur2.

FIG. 6 is a circuit block diagram illustrating the function calculation circuit 331 shown in FIG. 5 according to an embodiment of the present invention. In the embodiment shown in FIG. 6 , the function calculation circuit 331 includes a multiplication circuit 610 and a division circuit 620 . The multiplying circuit 610 is coupled to the variation calculating circuit 320 to receive the difference value DV. The multiplication circuit 610 may multiply the difference value DV by the difference value DV to generate a multiplication result 611 . The division circuit 620 is coupled to the multiplication circuit 610 to receive the multiplication result 611 . The division circuit 620 may divide the multiplication result 611 by the grayscale resolution GLmax to generate the function value FV.

FIG. 7 is a circuit block diagram illustrating the function calculation circuit 331 shown in FIG. 5 according to another embodiment of the present invention. In the embodiment shown in FIG. 7 , the function calculation circuit 331 includes a multiplication circuit 710 , a division circuit 720 and a multiplication circuit 730 . The multiplying circuit 710 is coupled to the variation calculating circuit 320 to receive the difference value DV. The multiplication circuit 710 may multiply the difference value DV by the difference value DV to generate a multiplication result 711 . The division circuit 720 is coupled to the multiplication circuit 710 to receive the multiplication result 711 . The division circuit 720 may divide the multiplication result 711 by the grayscale resolution GLmax to generate the division result 721 . The multiplication circuit 730 is coupled to the division circuit 720 to receive the division result 721 . The multiplication circuit 730 may multiply the division result 721 by the weight value W to generate the function value FV.

The weight value W may be provided by the judgment circuit 335 . The determination circuit 335 can compare the current sub-pixel data Cur1 with the previous sub-pixel data Pre to obtain a change relationship. The changing relationship includes “the current sub-pixel data Cur1 is greater than the previous sub-pixel data Pre” or “the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre”. The determination circuit 335 can know the polarity POL corresponding to the current frame period. The determination circuit 335 can dynamically adjust the weight value W according to the relationship between the polarity POL and the variation. For example, in the case where the polarity POL is expressed as "positive polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the weight value W may be set to W(P+L2H). In the case where the polarity POL is expressed as "positive polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the weight value W can be set to W(P+H2L). In the case where the polarity POL is expressed as "negative polarity", when the current sub-pixel data Cur1 is greater than (or equal to) the previous sub-pixel data Pre, the weight value W may be set to W(P-L2H). In the case where the polarity POL is expressed as "negative polarity", when the current sub-pixel data Cur1 is smaller than the previous sub-pixel data Pre, the weight value W can be set to W(P-H2L). The weight values W(P+L2H), W(P+H2L), W(P-L2H) and W(P-H2L) can be determined according to design requirements. For example, any one of the weight values W(P+L2H), W(P+H2L), W(P-L2H) and W(P-H2L) can be set as a real number from 0 to 2.

In some embodiments, the adjustment of the weight value W may also be related to panel characteristics. For example, for some display panels, the gate-to-source (Vgs) voltage of the TFT in positive polarity may be smaller than the gate-to-source voltage of the TFT in negative polarity. Therefore, the relationship between the weight value W(P+L2H) and W(P-L2H) can be "W(P+L2H) < W(P-L2H)", and the weight value W(P+H2L) The relationship with W(P-H2L) may be "W(P+H2L) < W(P-H2L)". For example, the weight value W(P+L2H) may be 0.1, and the weight value W(P-L2H) may be 0.15. As another example, for other display panels, the gate-to-source (Vgs) voltage of the TFT in positive polarity may be greater than the gate-to-source voltage of the TFT in negative polarity. Therefore, the relationship between the weight value W(P+L2H) and W(P-L2H) can be "W(P+L2H) > W(P-L2H)", and the weight value W(P+H2L) The relationship with W(P-H2L) may be "W(P+H2L) > W(P-H2L)".

FIG. 8 is a circuit block diagram illustrating the function calculation circuit 331 shown in FIG. 5 according to another embodiment of the present invention. In the embodiment shown in FIG. 8 , the function calculation circuit 331 includes a multiplication circuit 810 , a division circuit 820 , a multiplication circuit 830 and a look-up table 840 . The lookup table 840 can obtain the lookup value LT according to the difference value DV. The lookup table 840 may be defined according to design requirements. For example, in some embodiments, the lookup value LT may be a lookup value obtained from the lookup table shown in Table 1 above according to the difference value DV.

The multiplying circuit 810 is coupled to the variation calculating circuit 320 to receive the difference value DV. Multiplication circuit 810 may multiply the difference value DV to lookup value LT to produce multiplication result 811 . The division circuit 820 is coupled to the multiplication circuit 810 to receive the multiplication result 811 . The division circuit 820 may divide the multiplication result 811 by the grayscale resolution GLmax to generate the division result 821 . The multiplication circuit 830 is coupled to the division circuit 820 to receive the division result 821 . The multiplication circuit 830 may multiply the division result 821 by the weight value W to generate the function value FV. The weight value W may be provided by the judgment circuit 335 .

According to different design requirements, the implementation of the blocks of the above-mentioned variation calculation circuit 320 and/or compensation calculation circuit 330 may be hardware, firmware, software (program) or the aforementioned three A combination of many of them.

In terms of hardware, the above-mentioned blocks of the variation calculation circuit 320 and/or the compensation calculation circuit 330 can be implemented as logic circuits on an integrated circuit. The above-mentioned variation calculation circuit 320 and/or related functions of the compensation calculation circuit 330 may be implemented in hardware using hardware description languages (such as Verilog HDL or VHDL) or other suitable programming languages. For example, the above-mentioned related functions of the variation calculation circuit 320 and/or the compensation calculation circuit 330 can be implemented in one or more controllers, microcontrollers, microprocessors, application-specific integrated circuits (application-specific integrated circuits) circuit, ASIC), digital signal processor (DSP), Field Programmable Gate Array (FPGA) and/or various logic blocks, modules and circuits in other processing units.

In the form of software and/or firmware, the above-mentioned related functions of the variation calculation circuit 320 and/or the compensation calculation circuit 330 can be implemented as programming codes. For example, the above-mentioned variation calculation circuit 320 and/or compensation calculation circuit 330 may be implemented using general programming languages (eg, C, C++, or assembly language) or other suitable programming languages. The programming code may be recorded/stored in a recording medium, for example, the recording medium includes a read only memory (Read Only Memory, ROM), a storage device and/or a random access memory (Random Access Memory, RAM) . A computer, a central processing unit (CPU), a controller, a microcontroller or a microprocessor can read and execute the programming code from the recording medium, thereby achieving related functions. As the recording medium, a "non-transitory computer readable medium" can be used, and for example, a tape, a disk, a card, a semiconductor memory, a Programming logic circuits, etc. Furthermore, the program may be provided to the computer (or CPU) via any transmission medium (communication network, broadcast waves, or the like). The communication network is, for example, the Internet, wired communication, wireless communication, or other communication media.

To sum up, the polarity compensation device 300 and the polarity compensation method of the above embodiments can calculate the difference value DV between the current sub-pixel data Cur1 and the previous sub-pixel data Pre of the same data line. According to the difference value DV and the polarity POL, the compensation calculation circuit 330 may increase or decrease the current sub-pixel data Cur1 to generate the compensated sub-pixel data Cur2. Therefore, the polarity compensation device 300 can eliminate line afterimages as much as possible.

Although the present invention has been disclosed above by the embodiments, it is not intended to limit the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Therefore, The protection scope of the present invention shall be determined by the scope of the appended patent application.

10: Pre-processing circuit 20: Post-processing circuit 100: Display panel 300: Polarity compensation device 310: Buffer 320: Variation Calculation Circuit 330: Compensation calculation circuit 331: Function Computation Circuits 332: Subtraction Circuits 333: Adding Circuits 334: Selection circuit 335: Judgment circuit 610, 710, 730, 810, 830: Multiplication circuits 611, 711, 811: Multiplication result 620, 720, 820: division circuit 721, 821: division result 840: Lookup Table Cur1: current sub-pixel data Cur1+FV: Addition result Cur1-FV: Subtraction result Cur2: compensated sub-pixel data Din: Subpixel data Dout: Subpixel data DV: Difference value FV: function value GL: scan line GLmax: Grayscale resolution LT: lookup value POL: Polarity Pre: previous sub-pixel data S410～S430: Steps SL: data line SPU: Sub-pixel circuit SW1: Thin Film Transistor Vg: scan voltage Vs: drive voltage W: weight value

FIG. 1 is a schematic diagram of a circuit block of a sub-pixel circuit of a conventional display panel. FIG. 2 is a schematic circuit block diagram of a display device according to an embodiment of the present invention. FIG. 3 is a circuit block diagram illustrating the polarity compensation device shown in FIG. 2 according to an embodiment of the present invention. FIG. 4 is a schematic flowchart of a polarity compensation method according to an embodiment of the present invention. FIG. 5 is a circuit block diagram illustrating the compensation calculation circuit shown in FIG. 3 according to an embodiment of the present invention. FIG. 6 is a circuit block diagram illustrating the function calculation circuit shown in FIG. 5 according to an embodiment of the present invention. FIG. 7 is a circuit block diagram illustrating the function calculation circuit shown in FIG. 5 according to another embodiment of the present invention. FIG. 8 is a circuit block diagram illustrating the function calculation circuit shown in FIG. 5 according to another embodiment of the present invention.

300: Polarity compensation device 310: Buffer 320: Variation Calculation Circuit 330: Compensation calculation circuit Cur1: current subpixel data Cur2: compensated sub-pixel data DV: difference value POL: Polarity Pre: previous subpixel data

Claims (17)

A polarity compensation device, comprising: a variation calculation circuit configured to calculate a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data an identical data line belonging to a display panel; and a compensation calculation circuit coupled to the variation calculation circuit to receive the difference value, configured to convert the difference value into a function value using at least a look-up table, wherein the compensation The calculation circuit determines to increase or decrease the function value of the current sub-pixel data according to a polarity corresponding to the same frame period to generate a compensated sub-pixel data. A polarity compensation device, comprising: a variation calculation circuit configured to calculate a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data an identical data line belonging to a display panel; and a compensation calculation circuit, coupled to the variation calculation circuit to receive the difference value, configured to use the equation FV=|DV|*|DV|/GLmax to obtain the difference The value is converted into a function value, wherein FV represents the function value, DV represents the difference value, GLmax represents a grayscale resolution, and the compensation calculation circuit determines the current sub-pixel according to a polarity corresponding to the same frame period The data is incremented or decremented by the function value to generate a compensated sub-pixel data. A polarity compensation device, comprising: a change calculation circuit configured to calculate a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data data belonging to a same data line of a display panel as the previous sub-pixel data; and a compensation calculation circuit, coupled to the variation calculation circuit to receive the difference value, configured to use the equation FV=(|DV|*| DV|/GLmax)*W to convert the difference value into a function value, where FV represents the function value, DV represents the difference value, GLmax represents a gray scale resolution, W represents a weight value, and the compensation calculation circuit The function value is determined to increase or decrease the current sub-pixel data according to a polarity corresponding to the same frame period to generate a compensated sub-pixel data. The polarity compensation device of claim 3, wherein the compensation calculation circuit compares the current sub-pixel data with the previous sub-pixel data to obtain a variation relationship, and the compensation calculation circuit adjusts the weight according to the polarity and the variation relationship value. A polarity compensation device, comprising: a variation calculation circuit configured to calculate a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data an identical data line belonging to a display panel; and a compensation calculation circuit, coupled to the variation calculation circuit to receive the difference value, configured to use the equation FV=(|DV|*|LT|/GLmax)*W To convert the difference value into a function value, wherein FV represents the function value, DV represents the difference value, LT represents a lookup value obtained from a lookup table according to the difference value, GLmax represents a grayscale resolution, W represents a weight value, and the compensation calculation circuit determines to increase or decrease the function value of the current sub-pixel data according to a polarity corresponding to the same frame period to generate a compensated sub-pixel data. The polarity compensation device according to claim 1, wherein, in the case where the polarity is a positive polarity, when the current sub-pixel data is greater than or equal to the previous sub-pixel data, the compensation calculation circuit makes the current sub-pixel data increasing the function value to generate the compensated sub-pixel data; in the case of the positive polarity, when the current sub-pixel data is smaller than the previous sub-pixel data, the compensation calculation circuit reduces the current sub-pixel data the function value to generate the compensated sub-pixel data; in the case that the polarity is a negative polarity, when the current sub-pixel data is greater than or equal to the previous sub-pixel data, the compensation calculation circuit makes the current sub-pixel data reducing the function value to generate the compensated sub-pixel data; and in the case where the polarity is the negative polarity, when the current sub-pixel data is less than the previous sub-pixel data, the compensation calculation circuit causes the current sub-pixel data The function value is incremented to generate the compensated sub-pixel data. The polarity compensation device of claim 1, wherein the compensation calculation circuit comprises: a function calculation circuit, coupled to the variation calculation circuit to receive the difference value, configured to convert the difference value into the function value; a A subtraction circuit, coupled to the function calculation circuit to receive the function value, is configured to subtract the current sub-pixel data by the function value to generate a subtraction result; an addition circuit, coupled to the function calculation circuit to receive the function value a function value, configured to add the function value to the current sub-pixel data to generate an addition result; and a selection circuit, coupled to the subtraction circuit and the addition circuit, configured to automatically The state selects one of the subtraction result and the addition result as the compensated sub-pixel data. The polarity compensation device according to claim 7, wherein the compensation calculation circuit further comprises: a judgment circuit configured to control the selection circuit, wherein when the polarity is a positive polarity, when the current sub-pixel data is greater than or equal to the previous sub-pixel data, the determination circuit controls the selection circuit to select the addition result as the compensated sub-pixel data; in the case where the polarity is the positive polarity, when the current sub-pixel data is smaller than the previous sub-pixel data pixel data, the determination circuit controls the selection circuit to select the subtraction result as the compensated sub-pixel data; in the case where the polarity is a negative polarity, when the current sub-pixel data is greater than or equal to the previous sub-pixel data , the judgment circuit controls the selection circuit to select the subtraction result as the compensated sub-pixel data; and in the case of the negative polarity, when the current sub-pixel data is smaller than the previous sub-pixel data, the judgment circuit The selection circuit is controlled to select the addition result as the compensated sub-pixel data. The polarity compensation device of claim 7, wherein the function calculation circuit comprises: a multiplication circuit, coupled to the variation calculation circuit to receive the difference value, configured to multiply the difference value by the difference value to generate a a multiplication result; and a division circuit, coupled to the multiplication circuit to receive the multiplication result, configured The function value is generated by dividing the multiplication result by a grayscale resolution. The polarity compensation device of claim 7, wherein the function calculation circuit comprises: a first multiplication circuit, coupled to the variation calculation circuit to receive the difference value, configured to multiply the difference value by the difference value to obtain generating a multiplication result; a division circuit, coupled to the first multiplication circuit to receive the multiplication result, configured to divide the multiplication result by a grayscale resolution to generate a division result; and a second multiplication circuit, is coupled to the division circuit to receive the division result, and is configured to multiply the division result by a weight value to generate the function value. The polarity compensation device of claim 7, wherein the function calculation circuit comprises: a look-up table configured to obtain a look-up value according to the difference value; a first multiplication circuit, coupled to the variation calculation circuit for receiving The difference value is configured to multiply the difference value by the lookup value to generate a multiplication result; a division circuit, coupled to the first multiplication circuit to receive the multiplication result, is configured to divide the multiplication result by a grayscale resolution to generate a division result; and a second multiplication circuit coupled to the division circuit to receive the division result, configured to multiply the division result by a weight value to generate the function value. A polarity compensation method, comprising: calculating a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data belong to a display A same data line of the panel; A compensation calculation circuit converts the difference value into a function value using at least a look-up table; and the compensation calculation circuit determines to increase or decrease the function value for the current sub-pixel data according to a polarity corresponding to the same frame period , to generate a compensated sub-pixel data. A polarity compensation method, comprising: calculating a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data belong to a display A same data line of the panel; a compensation calculation circuit uses the equation FV=|DV|*|DV|/GLmax to convert the difference value into a function value, where FV represents the function value, DV represents the difference value, and GLmax represents a grayscale resolution; and the compensation calculation circuit determines to increase or decrease the function value of the current sub-pixel data according to a polarity corresponding to the same frame period to generate compensated sub-pixel data. A polarity compensation method, comprising: calculating a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data belong to a display An identical data line of the panel; the equation FV=(|DV|*|DV|/GLmax)*W is used by a compensation calculation circuit to convert the difference value into a function value, where FV represents the function value and DV represents the function value The difference value, GLmax represents a grayscale resolution, and W represents a weight value; and The compensation calculation circuit determines to increase or decrease the function value of the current sub-pixel data according to a polarity corresponding to the same frame period to generate compensated sub-pixel data. The polarity compensation method of claim 14, wherein converting the difference value into the function value further comprises: comparing the current sub-pixel data with the previous sub-pixel data by the compensation calculation circuit to obtain a variation relationship; and The weight value is adjusted by the compensation calculation circuit according to the polarity and the changing relationship. A polarity compensation method, comprising: calculating a difference value between a current sub-pixel data and a previous sub-pixel data in a same frame period, wherein the current sub-pixel data and the previous sub-pixel data belong to a display An identical data line of the panel; the equation FV=(|DV|*|LT|/GLmax)*W is used by a compensation calculation circuit to convert the difference value into a function value, where FV represents the function value and DV represents the function value For the difference value, LT represents a lookup value obtained from a lookup table according to the difference value, GLmax represents a grayscale resolution, and W represents a weight value; A polarity determines whether to increase or decrease the function value from the current sub-pixel data to generate a compensated sub-pixel data. The polarity compensation method of claim 12, wherein the determining to increase or decrease the function value for the current sub-pixel data comprises: When the polarity is a positive polarity, when the current sub-pixel data is greater than or equal to the previous sub-pixel data, the compensation calculation circuit increases the current sub-pixel data by the function value to generate the compensated sub-pixel data; in the case where the polarity is the positive polarity, when the current sub-pixel data is smaller than the previous sub-pixel data, the compensation calculation circuit reduces the current sub-pixel data by the function value to generate the compensated sub-pixel data; in the case where the polarity is a negative polarity, when the current sub-pixel data is greater than or equal to the previous sub-pixel data, the compensation calculation circuit reduces the current sub-pixel data by the function value to generate the compensated sub-pixel data; and in the case that the polarity is the negative polarity, when the current sub-pixel data is smaller than the previous sub-pixel data, the compensation calculation circuit increases the current sub-pixel data by the function value to generate the Compensate sub-pixel data.

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