A method and device for multi-scan charging compensation of AMOLED display screen

Abstract

The present invention discloses a method and device for multi-scan charging compensation of an AMOLED display screen, which eliminates the bright edge phenomenon under black characters on a white background by dynamically counting and adjusting the voltage of the current row data charged. The method includes: selecting the current point data and the pre-charged data of the current point; converting the current point data and the pre-charged data to voltage values ​​in the voltage domain; judging whether the difference between the current point voltage and the pre-charged voltage is less than a threshold value, if it is met, directly outputting the compensation value as 0; if it is not met, selecting the two-dimensional compensation table of the corresponding channel according to the channel to which the current point belongs, and performing a two-dimensional table lookup on the current point voltage and the pre-charged voltage to calculate the compensation voltage; converting the compensation voltage to compensation data in the data domain; finally, using the current point data and the compensation data to calculate the output data.

Description

Technical Field

[0001] The present invention relates to the field of AMOLED display technology, and in particular to a method and a device for multi-scanning charging compensation of an AMOLED display screen. Background Art

[0002] GOA (Gate Driven On Array) gate driver integration on the array substrate can realize the row-by-row scanning driving function of the AMOLED panel.

[0003] The AMOLED panel uses the signal waveform output by the GOA circuit to perform three steps for sub-pixels: capacitor voltage initialization, pixel charging, and pixel light display. In the multi-scan charging mode, the GOA circuit will perform capacitor voltage initialization and pixel charging for multiple times. The charged voltage of the pixel is not the same voltage every time. Only the last time is the voltage required for the actual current point display. The other charged voltages are all the data voltages of the previous row. When the data voltage of the previous row differs greatly from the data voltage of the current row, the brightness of the current row will be inaccurate. In actual observation, a bright edge appears below the black text in the white background and black text screen. The multi-scan charging method has certain advantages over the single-scan method in other display effects, and is also being used more and more.

[0004] The current single scan method is far inferior to the multi-scan method in terms of display effect. Therefore, a multi-scan charging compensation method for AMOLED display is proposed. By detecting the data voltage charged twice before and after, and performing real-time dynamic adjustment and compensation, the display anomaly of the black and white boundary can be effectively solved. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a method for multi-scanning charging compensation of an AMOLED display screen, comprising: a method for multi-scanning charging compensation of an AMOLED display screen, characterized in that it comprises:

[0006] Step 1: Select the current point data and the pre-charged data of the current point;

[0007] Step 2: Convert the current point data and pre-charge data to voltage values ​​in the voltage domain;

[0008] Step 3: Determine whether the difference between the current point voltage and the pre-charge voltage is less than a threshold value. If yes, directly output the compensation value as 0. If not, select the two-dimensional compensation table of the corresponding channel according to the channel to which the current point belongs, and perform a two-dimensional table lookup on the current point voltage and the pre-charge voltage to calculate the compensation voltage.

[0009] Step 4: converting the compensation voltage into compensation data in the data domain;

[0010] Step 5: Use the current point data and compensation data to calculate the output data.

[0011] Furthermore, the step 1 assumes that the displayed image is Line The input data for the columns is , and the pre-charge data of the current point is selected according to the multi-scan charging mode. If the pre-charge data is If the pre-charge data at the current point is the data before the row, then the pre-charge data at the current point is represented as Line Input data for columns , where the input data varies in the range of .

[0012] Furthermore, the current input data size of step 2 is linearly related to the actual voltage it represents. Assuming that the actual voltage value is obtained by the following formula

[0013] ,

[0014] in, is the scaling factor for data-to-voltage conversion.

[0015] Furthermore, the step three

[0016] No. Line The pre-charge data of the pixel point in the column is Line The current point voltage domain precharge voltage difference is

[0017] ,

[0018] If satisfied ,in, is the set threshold, then the compensation voltage value ,

[0019] If satisfied , then use Calculate the compensation voltage value;

[0020] is a two-dimensional lookup table, aisle, Channel and Each channel has its own set of two-dimensional lookup tables , , ,

[0021] If the current sub-pixel belongs to Channel, then ,

[0022] If the current sub-pixel belongs to Channel, then ,

[0023] If the current sub-pixel belongs to Channel, then ,

[0024] The number of binding points in each dimension of the two-dimensional lookup table is 17, and the binding point compensation voltage values ​​are 17*17 in total, which are ,

[0025] Assume that the voltage range is , then the interval between adjacent binding points is ,

[0026] ,

[0027] ,

[0028] ,

[0029] ,

[0030] in, represent The high 4 bits of represent The high 4 bits of represent Low Bit, represent Low Bit;

[0031] for and , the compensation voltage value is calculated using two-dimensional interpolation, the high and Used to conduct The binding point index gets the binding point value of the adjacent binding point, the low bit and Used as weights for 2D interpolation

[0032] ,

[0033] , .

[0034] Furthermore, the step four

[0035] The actual compensation voltage is linearly related to the compensation data size, and the relationship is expressed as follows:

[0036] .

[0037] Furthermore, the step five

[0038] Multi-scan charging compensation Line Output data of the column Using input data With compensation data Calculated

[0039] .

[0040] The present invention also provides a device for multi-scanning charging compensation of an AMOLED display screen, comprising:

[0041] Data storage unit: The data storage unit acts as a buffer for input values, storing the input values ​​several rows before the current point;

[0042] Data to voltage conversion unit: The data to voltage conversion unit receives the current input value and converts it into a voltage value to obtain the current input voltage, and receives the pre-charge data provided by the data storage unit, that is, the input value several rows ago, and converts it into a voltage value to obtain the pre-charge voltage, and transmits it to the voltage difference calculation unit;

[0043] Voltage difference calculation unit: calculates the difference between the current input voltage and the pre-charge voltage, and transmits the current input voltage, the pre-charge voltage and the difference between the two to the compensation voltage calculation unit;

[0044] Compensation voltage calculation unit: The compensation voltage calculation unit determines whether the difference between the current input voltage and the pre-charge voltage is less than the set threshold. If it is less than the set threshold, the compensation voltage is directly output as 0. If it is not less than the set threshold, the current input voltage and the pre-charge voltage are used to calculate the compensation voltage required for multi-scan charging compensation by table lookup and interpolation.

[0045] Voltage to data conversion unit: The voltage to data conversion unit converts the compensation voltage provided by the compensation voltage calculation unit into compensation data, and provides the compensation data to the output data calculation unit;

[0046] Output data calculation unit: uses the compensation data and current input data to calculate the compensated output data and output it.

[0047] The method and device for multi-scan charging compensation of an AMOLED display proposed in the present invention effectively solves the problem that the display effect of the AMOLED display is affected by the GOA (Gate Driven On Array) timing. The GOA timing is divided into a single-scan charging mode and a multi-scan charging mode. In the multi-scan charging mode, multiple pre-charge voltages are usually performed before charging the current point. The pre-charge voltage value is the data voltage of several rows before (usually the data voltage of the previous row). This will cause the brightness of the display screen to be affected by the pre-charge data voltage when the multi-scan charging mode is actually adopted, and a bright edge will appear under the black text on a white background. The multi-scan charging compensation method of the present invention can effectively eliminate the phenomenon of bright edges under black text on a white background by dynamically counting and adjusting the current row data voltage charged. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a flow chart of the multi-scan charging compensation method of the AMOLED display screen of the present invention;

[0049] Figure 2 Shown is a comparison of the normal effect (left) and the abnormal phenomenon displayed by multi-scan charging (right);

[0050] Figure 3 Shown is a schematic structural diagram of the multi-scan charging compensation device for an AMOLED display screen of the present invention. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] See also Figure 1-3 The present invention provides a method for multi-scanning charging compensation of an AMOLED display screen, comprising:

[0053] Step 1: Select the current point data and the pre-charged data of the current point;

[0054] Step 2: Convert the current point data and pre-charge data to voltage values ​​in the voltage domain;

[0055] Step 3: Determine whether the difference between the current point voltage and the pre-charge voltage is less than a threshold value. If yes, directly output the compensation value as 0. If not, select the two-dimensional compensation table of the corresponding channel according to the channel to which the current point belongs, and perform a two-dimensional table lookup on the current point voltage and the pre-charge voltage to calculate the compensation voltage.

[0056] Step 4: converting the compensation voltage into compensation data in the data domain;

[0057] Step 5: Use the current point data and compensation data to calculate the output data.

[0058] Assume that the displayed image Line The input data for the columns is , and the pre-charge data of the current point is selected according to the multi-scan charging mode. If the pre-charge data is If the pre-charge data at the current point is the data before the row, then the pre-charge data at the current point is represented as Line Input data for columns , where the input data range is .

[0059] Furthermore, the current input data size of step 2 is linearly related to the actual voltage it represents. Assuming that the actual voltage value is obtained by the following formula

[0060] ,

[0061] in, is the scaling factor for data-to-voltage conversion.

[0062] Step 3

[0063] No. Line The pre-charge data of the pixel point in the column is Line The current point voltage domain precharge voltage difference is

[0064] ,

[0065] If satisfied ,in, is the set threshold, then the compensation voltage value ,

[0066] If satisfied , then use Calculate the compensation voltage value;

[0067] is a two-dimensional lookup table, aisle, Channel and Each channel has its own set of two-dimensional lookup tables , , ,

[0068] If the current sub-pixel belongs to Channel, then ,

[0069] If the current sub-pixel belongs to Channel, then ,

[0070] If the current sub-pixel belongs to Channel, then ,

[0071] The number of binding points in each dimension of the two-dimensional lookup table is 17, and the binding point compensation voltage values ​​are 17*17 in total, which are ,

[0072] Assume that the voltage range is , then the interval between adjacent binding points is ,

[0073] ,

[0074] ,

[0075] ,

[0076] ,

[0077] in, represent The high 4 bits of represent The high 4 bits of represent Low Bit, represent Low Bit;

[0078] for and , the compensation voltage value is calculated using two-dimensional interpolation, the high and Used to conduct The binding point index gets the binding point value of the adjacent binding point, the low bit and Used as weights for 2D interpolation

[0079] ,

[0080] , .

[0081] Step 4: The actual compensation voltage is linearly related to the compensation data size, and the relationship is expressed as follows:

[0082] .

[0083] Step 5 Multi-scan charging compensation Line Output data of the column Using input data With compensation data Calculated

[0084] .

[0085] The present invention also provides a device for multi-scanning charging compensation of an AMOLED display screen, comprising:

[0086] Data storage unit: The data storage unit acts as a buffer for input values, storing the input values ​​several rows before the current point;

[0087] Data to voltage conversion unit: The data to voltage conversion unit receives the current input value and converts it into a voltage value to obtain the current input voltage, and receives the pre-charge data provided by the data storage unit, that is, the input value several rows ago, and converts it into a voltage value to obtain the pre-charge voltage, and transmits it to the voltage difference calculation unit;

[0088] Voltage difference calculation unit: calculates the difference between the current input voltage and the pre-charge voltage, and transmits the current input voltage, the pre-charge voltage and the difference between the two to the compensation voltage calculation unit;

[0089] Compensation voltage calculation unit: The compensation voltage calculation unit determines whether the difference between the current input voltage and the pre-charge voltage is less than the set threshold. If it is less than the set threshold, the compensation voltage is directly output as 0. If it is not less than the set threshold, the current input voltage and the pre-charge voltage are used to calculate the compensation voltage required for multi-scan charging compensation by table lookup and interpolation.

[0090] Voltage to data conversion unit: The voltage to data conversion unit converts the compensation voltage provided by the compensation voltage calculation unit into compensation data, and provides the compensation data to the output data calculation unit;

[0091] Output data calculation unit: uses the compensation data and current input data to calculate the compensated output data and output it.

[0092] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0093] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is limited by the appended claims and their equivalents.

Claims

1. A method for multi-scan charging compensation of an AMOLED display screen, characterized in that: include: Step 1: Select the current point data and the pre-charged data of the current point; Step 2: Convert the current point data and pre-charge data to voltage values ​​in the voltage domain; Step 3: Determine whether the difference between the current point voltage and the pre-charge voltage is less than a threshold value. If yes, directly output the compensation value as 0. If not, select the two-dimensional compensation table of the corresponding channel according to the channel to which the current point belongs, and perform a two-dimensional table lookup on the current point voltage and the pre-charge voltage to calculate the compensation voltage. Step 4: converting the compensation voltage into compensation data in the data domain; Step 5: Use the current point data and compensation data to calculate the output data; The step 1 assumes that the display image Line The input data for the columns is , and the pre-charge data of the current point is selected according to the multi-scan charging mode. If the pre-charge data is If the pre-charge data at the current point is the data before the row, then the pre-charge data at the current point is represented as Line Input data for columns , where the input data varies in the range of , where k is an integer; In step 2, the current point input data size is linearly related to the actual voltage it represents. Assuming that the actual voltage value is obtained by the following formula ， in, is the scaling factor for data-to-voltage conversion; Step three No. Line The pre-charge data of the pixel point in the column is Line The current point voltage domain precharge voltage difference is ， If satisfied ,in, is the set threshold, then the compensation voltage value , If satisfied , then use Calculate the compensation voltage value; is a two-dimensional lookup table, aisle, Channel and Each channel has its own set of two-dimensional lookup tables , , , If the current sub-pixel belongs to Channel, then , If the current sub-pixel belongs to Channel, then , If the current sub-pixel belongs to Channel, then , The number of binding points in each dimension of the two-dimensional lookup table is 17, and the binding point compensation voltage values ​​are 17*17 in total, which are , Assume that the voltage range is , m is an integer, then the interval between adjacent binding points is , ， ， ， ， in, represent The high 4 bits of represent The high 4 bits of represent Low Bit, represent Low Bit; for and , the compensation voltage value is calculated using two-dimensional interpolation, the high and Used to conduct The binding point index gets the binding point value of the adjacent binding point, the low bit and Used as weights for 2D interpolation ， ， 。 2. The method for multi-scanning charging compensation of an AMOLED display screen according to claim 1, characterized in that: Step 4 The actual compensation voltage is linearly related to the compensation data size, and the relationship is expressed as follows: 。 3. The method for multi-scanning charging compensation of an AMOLED display screen according to claim 2, characterized in that: Step 5 Multi-scan charging compensation Line Output data of the column Using input data With compensation data Calculated 。 4. A device for multi-scanning charging compensation of an AMOLED display screen, used to implement any one of the multi-scanning charging compensation methods for an AMOLED display screen as described in claims 1-3, characterized in that: include Data storage unit: The data storage unit acts as a buffer for input values, storing the input values ​​several rows before the current point; Data to voltage conversion unit: The data to voltage conversion unit receives the current input value and converts it into a voltage value to obtain the current input voltage, and receives the pre-charge data provided by the data storage unit, that is, the input value several rows ago, and converts it into a voltage value to obtain the pre-charge voltage, and transmits it to the voltage difference calculation unit; Voltage difference calculation unit: calculates the difference between the current input voltage and the pre-charge voltage, and transmits the current input voltage, the pre-charge voltage and the difference between the two to the compensation voltage calculation unit; Compensation voltage calculation unit: The compensation voltage calculation unit determines whether the difference between the current input voltage and the pre-charge voltage is less than the set threshold. If it is less than the set threshold, the compensation voltage is directly output as 0. If it is not less than the set threshold, the current input voltage and the pre-charge voltage are used to calculate the compensation voltage required for multi-scan charging compensation by table lookup and interpolation. Voltage to data conversion unit: The voltage to data conversion unit converts the compensation voltage provided by the compensation voltage calculation unit into compensation data, and provides the compensation data to the output data calculation unit; Output data calculation unit: uses the compensation data and current input data to calculate the compensated output data and output it.

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