Driving method and driving device of display screen, display device and electronic equipment

Abstract

The invention provides a driving method and a driving device of a display screen, a display device and electronic equipment, relates to the technical field of display, and aims to solve the problem that an R / G / BData value of an interpolation Band cannot be calculated in an existing linear interpolation mode. The driving method of the display screen comprises the following steps: providing a current display brightness value of the display screen; determining a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value, and generating a linear interpolation instruction based on the linear interpolation independent variable; and according to the linear interpolation instruction, performing linear interpolation on a first pixel data voltage value corresponding to the first display brightness value and a second pixel data voltage value corresponding to the second display brightness value to obtain a current pixel data voltage value corresponding to the current display brightness value.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a display screen driving method, a driving device, a display device and an electronic device. Background Art

[0002] High-precision frequency conversion technology is becoming the mainstream of the market due to its advantages such as low power consumption, excellent frequency switching effect, and high-precision refresh frequency. However, when using high-precision frequency conversion technology to drive pixels, the anode voltage of the light-emitting element in the pixel will undergo multiple resets, causing the driving current of the light-emitting element to change frequently, making it easier to expose the non-uniformity of the driving transistor in the pixel driving circuit under low-brightness and low-grayscale display conditions, which will cause the problem of low-grayscale image quality deterioration. The current conventional means of optimizing image quality include: by adjusting the anode reset voltage of the light-emitting element to be positively biased towards the cathode voltage of the light-emitting element under low brightness, increasing the proportion of the influence of the anode reset on the low-grayscale image quality.

[0003] The frequent changes in the driving current of the light-emitting element and the driving current of the driving transistor have a reduced impact on the low grayscale image quality, resulting in the low grayscale color accuracy offset problem between low-brightness bands in the high-frequency PWM dimming mode, making it impossible to use the existing linear interpolation method to calculate the R / G / B Data value of the interpolated band. Summary of the invention

[0004] The object of the present invention is to provide a display screen driving method, a driving device, a display device and an electronic device, which are used to solve the problem that the low grayscale color accuracy between low-brightness bands in the high-frequency PWM dimming mode is offset, resulting in the inability to use the existing linear interpolation method to calculate the R / G / B Data value of the interpolated band.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] A first aspect of the present invention provides a method for driving a display screen, comprising:

[0007] Provide the current display brightness value of the display screen;

[0008] According to the current display brightness value, determine a linear interpolation independent variable corresponding to the current display brightness value, and generate a linear interpolation instruction based on the linear interpolation independent variable, wherein the linear interpolation instruction instructs: perform linear interpolation based on the linear interpolation independent variable;

[0009] According to the linear interpolation instruction, linear interpolation is performed on the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value to obtain a current pixel data voltage value corresponding to the current display brightness value; the first display brightness value is less than the current display brightness value and is adjacent to the current display brightness value, and the second display brightness value is greater than the current display brightness value and is adjacent to the current display brightness value.

[0010] Optionally, the driving method further includes:

[0011] storing the mapping relationship between different display brightness values ​​and corresponding linear interpolation independent variables in a first lookup table;

[0012] The step of determining the linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value specifically includes:

[0013] According to the current display brightness value, a linear interpolation independent variable corresponding to the current display brightness value is searched in the first lookup table.

[0014] Optionally, the first lookup table indicates that: the linear interpolation independent variable corresponding to the display brightness value less than or equal to the first threshold is the pulse width modulation duty cycle; the linear interpolation independent variable corresponding to the display brightness value greater than the first threshold is the display brightness value.

[0015] Optionally, the step of performing linear interpolation on the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value according to the linear interpolation instruction specifically includes:

[0016] Calculate the slope k:

[0017]

[0018] Wherein, Data1 is the first pixel data voltage value, Data2 is the second pixel data voltage value, Variable1 is the linear interpolation independent variable corresponding to the first display brightness value, and Variable2 is the linear interpolation independent variable corresponding to the second display brightness value;

[0019] Calculate the difference of the independent variable dVariable:

[0020] dVariable=Variable-Variable1

[0021] Among them, Variable is the linear interpolation independent variable corresponding to the current display brightness value;

[0022] Calculate the interpolation increment dy:

[0023] dy=k*dVariable

[0024] Calculate the difference result Data:

[0025] Data=Data1+dy

[0026] Data is the current pixel data voltage value corresponding to the current display brightness value.

[0027] Optionally, the driving method further includes:

[0028] storing pixel data voltage values ​​corresponding to different display brightness values ​​in a second lookup table;

[0029] According to the current display brightness value, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are searched in the second lookup table.

[0030] Optionally, the driving method further includes:

[0031] The current pixel data voltage value obtained by linear interpolation is written into the corresponding register.

[0032] Based on the technical solution of the above display screen driving method, the second aspect of the present invention provides a display screen driving device, comprising:

[0033] An input buffer module, used for providing the current display brightness value of the display screen;

[0034] A control module, configured to determine a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value, and generate a linear interpolation instruction based on the linear interpolation independent variable, wherein the linear interpolation instruction instructs: performing linear interpolation based on the linear interpolation independent variable;

[0035] A linear interpolation module is used to perform linear interpolation on a first pixel data voltage value corresponding to a first display brightness value and a second pixel data voltage value corresponding to a second display brightness value according to the linear interpolation instruction to obtain a current pixel data voltage value corresponding to a current display brightness value; the first display brightness value is less than the current display brightness value and is adjacent to the current display brightness value, and the second display brightness value is greater than the current display brightness value and is adjacent to the current display brightness value.

[0036] Optionally, the driving device further includes:

[0037] A storage module, used for storing the mapping relationship between different display brightness values ​​and corresponding linear interpolation independent variables in a first lookup table;

[0038] The control module is specifically configured to: search the first lookup table for a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value.

[0039] Optionally, the first lookup table indicates that: the linear interpolation independent variable corresponding to the display brightness value less than or equal to the first threshold is the pulse width modulation duty cycle; the linear interpolation independent variable corresponding to the display brightness value greater than the first threshold is the display brightness value.

[0040] Optionally, the linear interpolation module is specifically used for:

[0041] Calculate the slope k:

[0042]

[0043] Wherein, Data1 is the first pixel data voltage value, Data2 is the second pixel data voltage value, Variable1 is the linear interpolation independent variable corresponding to the first display brightness value, and Variable2 is the linear interpolation independent variable corresponding to the second display brightness value;

[0044] Calculate the difference of the independent variable dVariable:

[0045] dVariable=Variable-Variable1

[0046] Among them, Variable is the linear interpolation independent variable corresponding to the current display brightness value;

[0047] Calculate the interpolation increment dy:

[0048] dy=k*dVariable

[0049] Calculate the difference result Data:

[0050] Data=Data1+dy

[0051] Data is the current pixel data voltage value corresponding to the current display brightness value.

[0052] Optionally, the storage module is further used for:

[0053] storing pixel data voltage values ​​corresponding to different display brightness values ​​in a second lookup table;

[0054] According to the current display brightness value, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are searched in the second lookup table.

[0055] Optionally, the driving device further includes:

[0056] The register output module is used to write the current pixel data voltage value obtained through linear interpolation into the corresponding register.

[0057] Based on the technical solution of the driving device of the above display screen, a third aspect of the present invention provides a display device, including the driving device of the above display screen.

[0058] Based on the technical solution of the above-mentioned display screen driving method, the fourth aspect of the present invention provides an electronic device, including a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the above-mentioned display screen driving method are implemented.

[0059] Based on the technical solution of the above-mentioned method for driving a display screen, the fifth aspect of the present invention provides a readable storage medium, on which a program or instruction is stored, and when the program or instruction is executed by a processor, the method for driving the above-mentioned display screen is implemented.

[0060] In the technical solution provided by the present invention, when the frequent changes in the driving current of the light-emitting element and the driving current of the driving transistor have a reduced impact on the low grayscale image quality, resulting in the problem of low grayscale color accuracy offset between low-brightness Bands in the high-frequency PWM dimming mode, it is possible to achieve the common benefits of two types of undesirable effects, namely, low grayscale CIE deflection and high grayscale DL / L jump of the interpolation Band, by setting PWM Duty as a linear interpolation independent variable in the low-brightness and low PWM Duty segment. BRIEF DESCRIPTION OF THE DRAWINGS

[0061] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0062] Figure 1 A schematic diagram of the circuit principle of a pixel driving circuit provided by an embodiment of the present invention;

[0063] Figure 2 A timing diagram of high-precision frequency conversion and Frame Skip frequency conversion provided by an embodiment of the present invention;

[0064] Figure 3 A schematic diagram of the mapping relationship between maximum brightness and PWM Duty provided in an embodiment of the present invention;

[0065] Figure 4 The corresponding CIE color accuracy of different modes in Table 1 is shown;

[0066] Figure 5 The schematic diagram of the response current of each sub-pixel under high-precision variable frequency coupling high-frequency PWM dimming is shown;

[0067] Figure 6 To calculate the difference between the low grayscale G Data between Bands and the target expected value using the existing linear interpolation relationship;

[0068] Figure 7 To calculate the difference between the R Data of the low gray scale between bands and the target expected value using the existing linear interpolation relationship;

[0069] Figure 8 To calculate the difference between the B Data of the low gray scale between Bands and the target expected value using the existing linear interpolation relationship;

[0070] Figure 9-Figure 14 The changes of the expected value of R / G / B Data, the linear interpolation of R / G / B Data obtained by taking DBV as the independent variable, and the linear interpolation of R / G / B Data obtained by taking PWM as the independent variable under different grayscales;

[0071] Fig.15 A schematic diagram of the power function relationship between PWM Duty and DBV provided in an embodiment of the present invention;

[0072] Fig.16 A schematic diagram of a driving device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0073] In order to further illustrate the display screen driving method, driving device, display device and electronic device provided by the embodiments of the present invention, a detailed description is given below in conjunction with the accompanying drawings.

[0074] An organic light emitting diode display product includes a plurality of sub-pixels, each of which includes a coupled sub-pixel driving circuit and a light emitting element. Figure 1 As shown, a sub-pixel driving circuit with an 8T1C (including 8 transistors and 1 capacitor) circuit structure and a light-emitting element (OLED) coupled to the sub-pixel driving circuit are illustrated.

[0075] The sub-pixel driving circuit comprises:

[0076] The first reset transistor T1 has a gate coupled to the first reset signal input terminal ResetP, a first electrode coupled to the first initialization signal input terminal VREFN1, and a second electrode coupled to the second electrode of the driving transistor DTFT.

[0077] The second reset transistor T7, the gate of the second reset transistor T7 is coupled to the second reset signal input terminal ResetH, the first electrode of the second reset transistor T7 is coupled to the second initialization signal input terminal VREFN2, and the second electrode of the second reset transistor T7 is coupled to the anode of the light emitting element.

[0078] The third reset transistor T8 has a gate coupled to the second reset signal input terminal ResetH, a first electrode coupled to the third initialization signal input terminal VREFN3, and a second electrode coupled to the first electrode of the driving transistor DTFT.

[0079] The data writing transistor T4 has a gate coupled to the first scanning signal input terminal Gate P, a first electrode coupled to the data signal input terminal Vdata, and a second electrode coupled to the first electrode of the driving transistor DTFT.

[0080] A power control transistor T5, wherein the gate of the power control transistor T5 is coupled to the light emitting control signal input terminal EM, the first electrode of the power control transistor T5 is coupled to the power signal input terminal VDD, and the second electrode of the power control transistor T5 is coupled to the first electrode of the driving transistor DTFT.

[0081] A light emitting control transistor T6, wherein the gate of the light emitting control transistor T6 is coupled to the light emitting control signal input terminal EM, the first electrode of the light emitting control transistor T6 is coupled to the second electrode of the driving transistor DTFT, the second electrode of the light emitting control transistor T6 is coupled to the anode of the light emitting element, and the cathode of the light emitting element receives the VSS signal.

[0082] The compensation transistor T2 has a gate coupled to the second scan signal input terminal Gate N, a first electrode coupled to the second electrode of the drive transistor DTFT, and a second electrode coupled to the gate of the drive transistor DTFT.

[0083] A first plate of the storage capacitor Cst is coupled to the gate of the driving transistor DTFT, and a second plate of the storage capacitor Cst is coupled to the power signal input terminal VDD.

[0084] like Figure 2As shown, unlike the Frame Skip frequency conversion that realizes the refresh frame and the hold frame as a complete frame respectively, when the high-precision frequency conversion technology is used to drive the sub-pixels, the refresh frame and the hold frame are used as sub-frames in a complete frame to achieve a high refresh frequency for the anode of the light-emitting element, thereby achieving excellent frequency switching effect and better power consumption benefits. It is worth noting that during the frequency switching process, the display screen can be driven by a combination of refresh frames and hold frames. In the refresh frame, the new data voltage is charged and applied to the gate of the driving transistor. In the hold frame, the data write transistor and the compensation transistor are kept in the off state for a long time, and the data voltage of the previous frame is maintained and used as it is.

[0085] However, the multiple resets of the anode of the light-emitting element under high-precision frequency conversion and the multiple switches of the emission signal (i.e., the light-emitting control signal input to the light-emitting control signal input terminal EM) under low brightness will increase the refresh frequency of the anode of the light-emitting element, and the light-emitting element driving current I under low brightness will increase. OLED It can be equivalent to the driving current I of the driven transistor DTFT TFT , light-emitting element parasitic capacitance charging and discharging current I Cap The leakage current I VREFN2 In order to avoid the high-precision frequency conversion driving transistor DTFT driving current I TFT The problem of poor uniformity of low grayscale image quality caused by frequent changes is solved by adjusting the anode reset voltage of the light-emitting element to be positively biased towards the cathode voltage of the light-emitting element to increase the proportion of the anode reset effect on the low grayscale image quality, that is: I TFT +I VREFN2 ≈I OLED +I Cap .

[0086] Using high-frequency PWM (pulse width modulation) to modulate the brightness of the low-brightness range is an effective dimming method to avoid uneven display and relieve visual fatigue of the human eye. The principle is to increase the I of the emission stage by controlling the ratio of the on and off time of the sub-pixel (duty cycle). OLED , thereby avoiding the problem of poor uniformity of the driving transistor.

[0087] Usually, when setting the PWM Duty (pulse width modulation duty cycle) of the adjustable Band (brightness range), the linear relationship between the Band's 255 grayscale brightness (maximum brightness) and the PWM Duty setting is considered. Figure 3 As shown, Figure 3 The diagram below shows the mapping relationship between maximum brightness and PWM Duty; Figure 3 The horizontal axis represents PWM Duty, and the vertical axis represents Lv, with the unit of nit.

[0088] As shown in Table 1, the mapping relationship between the display brightness value (DBV), the debugging target brightness value (Lv), and the PWM duty cycle under various different modes (MODE) is illustrated. APL1 (20%) illustrated in Table 3 represents local highlight, with the luminous area accounting for 20%; HBM represents full-screen highlight; normall~normal10 represent ten groups of data corresponding to normal display brightness. The display brightness value (DBV) and the debugging target brightness value (Lv) have a specific one-to-one mapping relationship. It should be noted that DBV is an objective value that characterizes the brightness level of the display screen and is adjustable. In the present invention, the adjustment range is 1~4095, but is not limited to this.

[0089] MODE DBV Lv Duty / % APL1 (20%) 4095 2500 97.13 HBM 3880 1600 97.13 normal_1 3500 1200 97.13 normal_2 2400 500 97.13 normal_3 1510 150 97.13 normal_4 1198 90 97.13 normal_5 1197 89.9 85 normal_6 910 50 51 normal_7 580 20 25 normal_8 410 10 17 normal_9 240 5 13 normal_10 3 2 10

[0090] Table 1

[0091] For low grayscale display under high-precision variable frequency coupled high-frequency PWM dimming, the following factors affect it: (1) the driving current of the driving transistor changes frequently; (2) the proportion of the influence of anode reset on low grayscale image quality increases; (3) the number of times the emission signal jumps from low level to high level under high-frequency PWM dimming increases, and the frequent changes in anode potential cause I TFT Frequent changes; that is, the response current difference of each pulse R, G, B sub-pixel under high-precision frequency conversion coupling high-frequency PWM dimming becomes larger, the current is unstable, and the color ratio is unbalanced. For details, see Figure 5 Under high-precision variable frequency coupled high-frequency PWM dimming, the B sub-pixel response current has a gentle high level, and the R and G sub-pixel response currents are both shown as triangular pulses. Figure 5 The horizontal axis in represents time, in μm; Figure 5 The vertical axis represents the current.

[0092] Therefore, the R / G / B Data charging voltage ratio of the low grayscale between the interpolation bands cannot be calculated using the existing linear interpolation relationship (that is, DBV is used as the independent variable). Otherwise, the low grayscale image will lose CIE color accuracy when sliding the brightness bar. For details, see Figure 4 , Figure 4 The corresponding CIE color accuracy of different modes in Table 1 is shown. Figure 4 It can be seen that the CIE color accuracy corresponding to normal7~normal10 is deviated.

[0093] It should be noted that the charging voltage ratio refers to the voltage ratio required by the RGB channels under different brightness conditions. Usually, the linear interpolation relationship with DBV as the independent variable can be used to predict the voltage ratio under different DBV (display brightness value), but in the above case, due to the influence of high-precision frequency conversion and PWM dimming, the response of the R / G / B channels is no longer linear, so the linear difference relationship with DBV as the independent variable is no longer applicable.

[0094] It is worth noting that CIE color accuracy characterizes the accuracy of color reproduction of display devices or color reproduction systems, providing a standard way to describe and measure color, such as XYZ color space. Linear interpolation is a basic method for generating intermediate Band Data Register values ​​between two debugging Bands. It is based on the concept of a straight line equation and calculates the value of the intermediate point by proportionally distributing between two points.

[0095] like Figure 6 , Figure 7 , Figure 8 As shown, the existing linear interpolation relationship (DBV as the independent variable) is used to calculate the difference between the R / G / B Data of the low grayscale between bands and the target expected value. The target expected value is the optical adjustment value corresponding to the target brightness and the corresponding PWM Duty setting. Figure 6-Figure 8 The horizontal axis represents DBV, and the vertical axis represents Data value. Figure 6 The expected value of G Data (solid line) and the linear interpolation of G Data (dashed line) are shown in FIG. Figure 7 The expected value of R Data (solid line) and the linear interpolation of R Data (dashed line) are shown in the figure; Figure 8 The B Data expected value (solid line) and B Data linear interpolation (dashed line) are shown in FIG. It can be seen that the R and G Data calculated values ​​are significantly different from the target expected values.

[0096] The common solutions to the above problems are: (1) adding a debugging Band to the low-brightness and low-PWM segment to increase the interpolation points of the existing linear interpolation, but this method increases the Tact Time and occupies additional IC ROM memory; (2) in the low-brightness and low-PWM segment (low duty cycle segment) where the CIE deflection is serious, the PWM Duty difference between adjacent interpolated Bands is reduced, but this method will worsen the CIE deflection problem of another PWM segment, and will induce brightness flicker and other problems because the PWM Duty and maximum brightness (255 grayscale brightness) are set to a nonlinear relationship.

[0097] See also Fig.16 , an embodiment of the present invention provides a method for driving a display screen, comprising:

[0098] Provide the current display brightness value of the display screen;

[0099] According to the current display brightness value, determine a linear interpolation independent variable corresponding to the current display brightness value, and generate a linear interpolation instruction based on the linear interpolation independent variable, wherein the linear interpolation instruction instructs: perform linear interpolation based on the linear interpolation independent variable;

[0100] According to the linear interpolation instruction, linear interpolation is performed on the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value to obtain a current pixel data voltage value corresponding to the current display brightness value; the first display brightness value is less than the current display brightness value and is adjacent to the current display brightness value, and the second display brightness value is greater than the current display brightness value and is adjacent to the current display brightness value.

[0101] In more detail, by Figure 6 , Figure 7 and Figure 8 It can be seen that the calculated data values ​​of low grayscale R and G are significantly different from the target expected values, especially in the range of DBV<580 (corresponding to Normal 7 to Normal 10), so it is necessary to measure the functional relationship between the expected data values ​​of low grayscale R and G and DBV. Through polynomial fitting, the functional relationship between the expected data values ​​of low grayscale R and G and DBV satisfies the following:

[0102] y=ax 4 +bx 3 +cx 2 +dx

[0103] Where y is the expected value of Data and x is the DBV value. Derivatively, we get:

[0104]

[0105] It can be seen that the rate of change of Data relative to DBV is a cubic polynomial, which is not compatible with a linear relationship. When x changes, its slope changes further away from the constant. Therefore, it is necessary to find independent variables other than DBV to make the change of Data relative to the independent variable as close to a linear relationship as possible (based on the maturity and stability of the existing Driver IC linear interpolation module). Comprehensively considered, the power function relationship between PWM Duty and DBV can effectively improve the above problems.

[0106] like Fig.15 As shown, the power function relationship between PWM Duty and DBV satisfies the following:

[0107] u=f(x 2 )

[0108] Where u is PWM Duty, and x is DBV value. Substituting the relationship between Data and DBV, we get:

[0109]

[0110] Taking its derivative we get:

[0111]

[0112] Where a, b, c, d are the weights of each component of the polynomial. It can be seen that the rate of change of Data relative to PWM Duty is a polynomial with a highest power of 1, and its slope changes less with u than with DBV. When the weights of b and d are low, it can be obtained that its rate of change is close to a linear relationship.

[0113] In order to describe the matching degree between the interpolation relationship and the expected value, the Pearson correlation coefficient (r) is introduced to quantify the matching degree between two variables X and Y. The calculation formula is:

[0114]

[0115] In DBV<580 (corresponding to Normal 7 to Normal 10), PWM Duty is introduced as the independent variable of the linear interpolation module (the existing IC supports PWM Duty accuracy consistent with DBV accuracy, both are 12 bits). From Table 2, and Figure 9-Figure 15 It can be seen that after introducing PWM Duty as the linear interpolation independent variable, the matching degree r of the interpolation relationship and the expected value at low grayscale is closer to 1, and similarly, the matching degree r of the interpolation relationship and the expected value at high grayscale is closer to 1; it should be noted that DataRegister in Table 1 is the Data voltage value written to the N1 (i.e., the gate of the driving transistor) node through the driving transistor.

[0116]

[0117] Table 2

[0118] In more detail, Fig. 9 As shown, it illustrates the changes of the expected value of GData, the linear interpolation of GData obtained by taking DBV as the independent variable, and the linear interpolation of GData obtained by taking PWM as the independent variable with the change of DBV under low grayscale (16gray); it can be seen that the matching degree r between the linear interpolation of GData obtained by taking DBV as the independent variable and the expected value is 0.9906, and the matching degree r between the linear interpolation of GData obtained by taking PWM as the independent variable and the expected value is 0.9982.

[0119] like Fig.10As shown in the figure, the expected value of R Data, the linear interpolation of R Data obtained by taking DBV as the independent variable, and the linear interpolation of R Data obtained by taking PWM as the independent variable change with DBV at low grayscale (16gray). It can be seen that the matching degree r between the linear interpolation of R Data obtained by taking DBV as the independent variable and the expected value is 0.9830, and the matching degree r between the linear interpolation of R Data obtained by taking PWM as the independent variable and the expected value is 0.9916.

[0120] like Fig.11 As shown in the figure, the changes of the expected value of B Data, the linear interpolation of B Data obtained by taking DBV as the independent variable, and the linear interpolation of B Data obtained by taking PWM as the independent variable under low grayscale (16 gray) are illustrated; it can be seen that the matching degree r between the linear interpolation of B Data obtained by taking DBV as the independent variable and the expected value is 0.9965, and the matching degree r between the linear interpolation of B Data obtained by taking PWM as the independent variable and the expected value is 0.9971.

[0121] like Fig.12 As shown, it illustrates the changes of the expected value of G Data, the linear interpolation of G Data obtained by taking DBV as the independent variable, and the linear interpolation of G Data obtained by taking PWM as the independent variable with the change of DBV under high grayscale (255 gray); it can be seen that the matching degree r between the linear interpolation of G Data obtained by taking DBV as the independent variable and the expected value is 0.9982, and the matching degree r between the linear interpolation of G Data obtained by taking PWM as the independent variable and the expected value is 0.999.

[0122] like Fig.13 As shown, it illustrates the changes of the expected value of R Data, the linear interpolation of R Data obtained by taking DBV as the independent variable, and the linear interpolation of R Data obtained by taking PWM as the independent variable with DBV as the independent variable under high grayscale (255 gray); it can be seen that the matching degree r between the linear interpolation of R Data obtained by taking DBV as the independent variable and the expected value is 0.9984, and the matching degree r between the linear interpolation of R Data obtained by taking PWM as the independent variable and the expected value is 0.9991.

[0123] like Fig.14As shown in the figure, it illustrates the changes of the expected value of B Data, the linear interpolation of B Data obtained by taking DBV as the independent variable, and the linear interpolation of B Data obtained by taking PWM as the independent variable with the change of DBV under high gray scale (255 gray); it can be seen that the matching degree r between the linear interpolation of B Data obtained by taking DBV as the independent variable and the expected value is 0.9984, and the matching degree r between the linear interpolation of B Data obtained by taking PWM as the independent variable and the expected value is 0.9993.

[0124] From the above analysis, it can be seen that when DBV<580, PWM Duty as the independent variable of the linear interpolation module can effectively improve the poor CIE color deviation of low grayscale, and will not cause the DL / L brightness flicker problem of high grayscale (255); and through the power function relationship between PWM Duty and DBV, the Data-DBV nonlinear interpolation function under PWM Duty as the independent variable of the Data-Register linear interpolation module is realized. When DBV>580, the matching degree of using PWM Duty as the independent variable of the linear interpolation module is lower than that of using DBV as the independent variable of the linear interpolation module. The reason can be attributed to: the functional relationship between the expected value of Data and DBV changes, and the change of Data relative to the independent variable of DBV is closer to a linear relationship. Therefore, it is necessary to control the linear interpolation independent variable to switch from DBV to PWM Duty in the interval of DBV>580.

[0125] It should be noted that DL / L represents the change in display brightness level between two adjacent DBVs, that is, brightness accuracy.

[0126] In the driving method of the display screen provided by the present invention, the input buffer module first provides the current display brightness value (i.e., DVB value) of the display screen; then, according to the current display brightness value, the linear interpolation independent variable (DBV or PWM Duty) corresponding to the current display brightness value is determined, and a linear interpolation instruction is generated; then, according to the linear interpolation instruction, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are linearly interpolated to obtain the current pixel data voltage value corresponding to the current display brightness value. It should be noted that the input buffer is usually used to temporarily store input data for use in the interpolation process. Common implementations of the input buffer include: registers, static random access memory (SRAM).

[0127] It can be seen that in the driving method of the display screen provided by the present invention, the accuracy of linear interpolation between PWM modulation bands of the driver chip (Driver IC) using this method can be improved by controlling the adaptive switching of the linear interpolation independent variable about the Data Register, and the low grayscale CIE misalignment of the interpolation band can be improved. Therefore, when the frequent changes in the driving current of the light-emitting element superimpose the driving current of the driving transistor on the low grayscale image quality, and the low grayscale color accuracy offset problem between low-brightness bands in the high-frequency PWM dimming mode is derived, the driving method of the display screen provided by the embodiment of the present invention can achieve the common benefits of the two types of poor low grayscale CIE misalignment and high grayscale DL / L jump of the interpolation band by setting PWM Duty (pulse width modulation duty cycle) as the independent variable of the Data Register linear interpolation module in the low brightness and low PWM Duty segment.

[0128] In the display screen driving method provided by the present invention, it is not necessary to add an additional Tuning Band, thereby avoiding the need to increase ICROM memory.

[0129] Moreover, the Driver IC uses PWM Duty as an independent variable to perform linear interpolation on the Data Register, which is different from the existing project (in the traditional sense) that uses DBV as an independent variable to perform linear interpolation on the Data Register. By using PWMDuty as an independent variable to perform linear interpolation, it is equivalent to achieving nonlinear interpolation (i.e., polynomial function relationship) using DBV as an independent variable. Therefore, the present invention does not need to set additional modules such as logarithmic amplifiers on the existing framework to achieve nonlinear interpolation using DBV as an independent variable, thereby effectively reducing power consumption.

[0130] In some embodiments, the driving method further includes:

[0131] The mapping relationship between different display brightness values ​​and corresponding linear interpolation independent variables is stored in a first lookup table; exemplarily, the first lookup table indicates that: the linear interpolation independent variable corresponding to the display brightness value less than or equal to the first threshold is the pulse width modulation duty cycle; the linear interpolation independent variable corresponding to the display brightness value greater than the first threshold is the display brightness value. For example: the first threshold is 580, but is not limited thereto.

[0132] The step of determining the linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value specifically includes:

[0133] According to the current display brightness value, the linear interpolation independent variable corresponding to the current display brightness value is searched in the first lookup table. Exemplarily, when DBV changes, the independent variable of the Data Register linear interpolation is switched according to the LUT1 table control. For example, when DBV is less than 580, the Variable corresponding to the DBV is searched according to the LUT1 table to feedback that the independent variable is PWM Duty. When DBV is greater than 580, the Variable corresponding to the DBV is searched according to the LUT1 table to feedback that the independent variable is DBV.

[0134] Exemplarily, before performing Data Register linear interpolation, the mapping relationship between different DBV intervals and different independent variables is preset and stored in the first lookup table (LOOK-UP Table 1, LUT1), as shown in Table 3. The mapping relationship is generally debugged and confirmed in advance for small batch products according to BC setting (benchmark configuration). It should be noted that the second column PWM Duty (12bit) in Table 3 is the data stored in the register in digital form, and the third column PWM Duty is in percentage form. The data in the second and third columns correspond one to one and can be obtained by conversion. The fourth column Variable is the independent variable, and the fifth column Variable set is the independent variable configuration.

[0135] DBV(12bit) PWM Duty(12bit) PWM Dutv Variable Variable set 1 409 9.99％ 409 PWM 2 409 9.99％ 409 PWM 3 409 9.99％ 409 PWM ...... ...... ...... ...... PWM 578 1025 25.03％ 1025 PWM 579 1027 25.08％ 1027 PWM 580 1030 25.15％ 1030 / 580 DBV 581 1032 25.20％ 581 DBV 582 1034 25.25％ 582 DBV 583 1041 25.42％ 583 DBV ...... ...... ...... ...... DBV 1191 3447 84.18％ 1191 DBV 1192 3452 84.30％ 1192 DBV 1193 3458 84.44％ 1193 DBV

[0136] Table 3

[0137] In some embodiments, the step of linearly interpolating the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value according to the linear interpolation instruction specifically includes:

[0138] Calculate the slope k:

[0139]

[0140] Wherein, Data1 is the first pixel data voltage value, Data2 is the second pixel data voltage value, Variable1 is the linear interpolation independent variable corresponding to the first display brightness value, and Variable2 is the linear interpolation independent variable corresponding to the second display brightness value;

[0141] Calculate the difference of the independent variable dVariable:

[0142] dVariable=Variable-Variable1

[0143] Among them, Variable is the linear interpolation independent variable corresponding to the current display brightness value;

[0144] Calculate the interpolation increment dy:

[0145] dv=k*dVariable

[0146] Calculate the difference result Data:

[0147] Data=Data1+dy

[0148] Data is the current pixel data voltage value corresponding to the current display brightness value.

[0149] Exemplarily, the driving method further includes: storing pixel data voltage values ​​corresponding to different display brightness values ​​in a second lookup table (LOOK-UP Table2, LUT2); for example: see Table 4, which illustrates R / G / B pixel data voltage values ​​corresponding to different display brightness values.

[0150] According to the current display brightness value, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are searched in the second lookup table. Exemplarily, when DBV<580, the independent variable is PWM Duty, and when DBV is 280, the R / G / B DataRegister values ​​of the adjacent DBV endpoints are searched through the LUT2 table as Data1 and Data2.

[0151] DBV(12bit) PWM Duty(12bit) PWM Duty Variable Variable set R Data Register G Data Register B Data Register 3 409 9.99％ 409 PWM 898 574 1434 240 497 1214％ 497 PWM 924 650 1426 410 697 1702％ 697 PWM 942 742 1401 580 1030 2515％ 1030 PWM 954 806 1360 580 1030 2515％ 580 DBV 954 806 1360 910 2087 50.96％ 910 DBV 961 876 1279 1193 3458 84.44％ 1193 DBV 979 925 1233

[0152] Table 4

[0153] In some embodiments, the driving method further includes: writing the current pixel data voltage value obtained by linear interpolation into a corresponding register. Exemplarily, the result of linear interpolation is written into a Data register corresponding to the current DBV, that is, the output of the linear interpolation module is completed.

[0154] like Fig.16 As shown, an embodiment of the present invention further provides a driving device for a display screen, comprising:

[0155] An input buffer module, used for providing the current display brightness value of the display screen;

[0156] A control module is used to determine a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value, and generate a linear interpolation instruction based on the linear interpolation independent variable, wherein the linear interpolation instruction indicates: linear interpolation is performed based on the linear interpolation independent variable; exemplarily, the control module is a module for controlling the switching of the linear interpolation independent variable.

[0157] A linear interpolation module is used to perform linear interpolation on a first pixel data voltage value corresponding to a first display brightness value and a second pixel data voltage value corresponding to a second display brightness value according to the linear interpolation instruction to obtain a current pixel data voltage value corresponding to a current display brightness value; the first display brightness value is less than the current display brightness value and is adjacent to the current display brightness value, and the second display brightness value is greater than the current display brightness value and is adjacent to the current display brightness value.

[0158] It should be noted that the input buffer module, the control module, the storage module, the linear interpolation module, and the register output module all belong to the Driver IC. The linear interpolation module may include a command receiving unit, which is used to receive a linear difference instruction and search the LUT2 for a first pixel data voltage value corresponding to a first display brightness value and a second pixel data voltage value corresponding to a second display brightness value based on the instruction.

[0159] In the driving device provided by the embodiment of the present invention, the input buffer module provides the current display brightness value (i.e., DVB value) of the display screen; the control module determines the linear interpolation independent variable (DBV or PWM Duty) corresponding to the current display brightness value according to the current display brightness value, and generates a linear interpolation instruction; the linear interpolation module performs linear interpolation on the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value according to the linear interpolation instruction to obtain the current pixel data voltage value corresponding to the current display brightness value.

[0160] It can be seen that in the driving device provided in the embodiment of the present invention, the linear interpolation accuracy between PWM modulation bands of the driver chip (Driver IC) applying the method can be improved by controlling the adaptive switching of the linear interpolation independent variable about the Data Register, and the low grayscale CIE deflection of the interpolation band can be improved.

[0161] In some embodiments, the driving device further comprises:

[0162] A storage module, used for storing the mapping relationship between different display brightness values ​​and corresponding linear interpolation independent variables in a first lookup table;

[0163] The control module is specifically configured to: search the first lookup table for a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value.

[0164] Exemplarily, the storage module includes a static random access memory (SRAM), but is not limited thereto.

[0165] In some embodiments, the first lookup table indicates that: the linear interpolation independent variable corresponding to the display brightness value less than or equal to the first threshold is the pulse width modulation duty cycle; the linear interpolation independent variable corresponding to the display brightness value greater than the first threshold is the display brightness value.

[0166] In some embodiments, the linear interpolation module is specifically used for:

[0167] Calculate the slope k:

[0168]

[0169] Wherein, Data1 is the first pixel data voltage value, Data2 is the second pixel data voltage value, Variable1 is the linear interpolation independent variable corresponding to the first display brightness value, and Variable2 is the linear interpolation independent variable corresponding to the second display brightness value;

[0170] The independent variable difference dVariable is calculated by the subtractor included in the arithmetic logic unit in the linear interpolation module:

[0171] dVariable=Variable-Variable1

[0172] Among them, Variable is the linear interpolation independent variable corresponding to the current display brightness value;

[0173] The interpolation increment dy is calculated by the multiplier included in the arithmetic logic unit in the linear interpolation module:

[0174] dy=k*dVariable

[0175] The difference result Data is calculated by the adder included in the arithmetic logic unit in the linear interpolation module:

[0176] Data=Data1+dy

[0177] Data is the current pixel data voltage value corresponding to the current display brightness value.

[0178] In some embodiments, the storage module is further used to:

[0179] storing pixel data voltage values ​​corresponding to different display brightness values ​​in a second lookup table;

[0180] According to the current display brightness value, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are searched in the second lookup table.

[0181] In some embodiments, the driving device further comprises:

[0182] The register output module is used to write the current pixel data voltage value obtained through linear interpolation into the corresponding register.

[0183] An embodiment of the present invention further provides a display device, comprising the driving device of the display screen provided by the above embodiment.

[0184] Exemplarily, the display device includes an OLED display device, but is not limited thereto.

[0185] It should be noted that the display device can be any product or component with a display function, such as a television, a monitor, a digital photo frame, a mobile phone, a tablet computer, etc., wherein the display device also includes a flexible circuit board, a printed circuit board and a backplane, etc.

[0186] In the driving device provided in the above embodiment, the linear interpolation independent variable adaptive switching of the Data Register can be controlled to improve the linear interpolation accuracy between PWM modulation bands of the driver chip (Driver IC) using the method, and improve the low grayscale CIE deflection of the interpolation band. Therefore, the display device provided in the embodiment of the present invention also has the above beneficial effects when including the above driving device, which will not be described in detail here.

[0187] An embodiment of the present invention further provides an electronic device, including a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the display screen driving method provided in the above embodiment are implemented.

[0188] In the driving method provided in the above embodiment, the linear interpolation independent variable adaptive switching of the Data Register can be controlled to improve the accuracy of the linear interpolation between the PWM modulation bands of the driver chip (Driver IC) using this method, and improve the low grayscale CIE deflection of the interpolation band. Therefore, the electronic device provided in the embodiment of the present invention also has the above beneficial effects when executing the above driving method, which will not be repeated here.

[0189] An embodiment of the present invention further provides a readable storage medium, on which a program or instruction is stored. When the program or instruction is executed by a processor, the method for driving the display screen provided in the above embodiment is implemented.

[0190] The readable storage medium includes a computer-readable storage medium, such as a computer read-only memory ROM, a random access memory RAM, a magnetic disk or an optical disk, etc. In some examples, the readable storage medium may be a non-transitory readable storage medium.

[0191] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of a computer software product plus a necessary general hardware platform, and of course, can also be implemented by hardware. The computer software product is stored in a storage medium (such as ROM, RAM, disk, CD, etc.), including several instructions to enable a terminal or a network-side device to execute the methods described in each embodiment of the present application.

[0192] In the driving method provided in the above embodiment, the linear interpolation independent variable adaptive switching of the Data Register can be controlled to improve the accuracy of the linear interpolation between the PWM modulation bands of the driver chip (Driver IC) using the method, and improve the low grayscale CIE deflection of the interpolation band. Therefore, the readable storage medium provided in the embodiment of the present invention also has the above beneficial effects when storing the above driving method, which will not be repeated here.

[0193] It should be noted that the "same layer" in the embodiment of the present invention may refer to a film layer on the same structural layer. Or, for example, a film layer on the same layer may be a film layer for forming a specific pattern formed by the same film forming process, and then the film layer is patterned by the same mask through a single composition process to form a layer structure. Depending on the specific pattern, a single composition process may include multiple exposure, development or etching processes, and the specific pattern in the formed layer structure may be continuous or discontinuous. These specific patterns may also be at different heights or have different thicknesses.

[0194] In the various method embodiments of the present invention, the serial numbers of the steps cannot be used to limit the sequence of the steps. For ordinary technicians in this field, without paying creative work, changes to the sequence of the steps are also within the protection scope of the present invention.

[0195] It should be noted that each embodiment in this specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the method embodiment, since it is basically similar to the product embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the product embodiment.

[0196] Unless otherwise defined, the technical terms or scientific terms used in this disclosure should be understood by people with ordinary skills in the field to which the present invention belongs. "First", "second" and similar words used in this disclosure do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect", "couple" or "connected" and similar words are not limited to physical or mechanical connections, but can include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0197] It will be understood that when an element such as a layer, film, region, or substrate is referred to as being “on” or “under” another element, it can be “directly on” or “under” the other element or intervening elements may be present.

[0198] In the description of the above embodiments, specific features, structures, materials or characteristics may be combined in a suitable manner in any one or more embodiments or examples.

[0199] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for driving a display screen, characterized in that: include: Provide the current display brightness value of the display screen; According to the current display brightness value, determine a linear interpolation independent variable corresponding to the current display brightness value, and generate a linear interpolation instruction based on the linear interpolation independent variable, wherein the linear interpolation instruction instructs: perform linear interpolation based on the linear interpolation independent variable; According to the linear interpolation instruction, linearly interpolate the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value to obtain a current pixel data voltage value corresponding to the current display brightness value; The first display brightness value is smaller than the current display brightness value and is adjacent to the current display brightness value, and the second display brightness value is larger than the current display brightness value and is adjacent to the current display brightness value.

2. The method for driving a display screen according to claim 1, characterized in that: The driving method further comprises: storing the mapping relationship between different display brightness values ​​and corresponding linear interpolation independent variables in a first lookup table; The step of determining the linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value specifically includes: According to the current display brightness value, a linear interpolation independent variable corresponding to the current display brightness value is searched in the first lookup table.

3. The method for driving a display screen according to claim 2, characterized in that: The first lookup table indicates that: the linear interpolation independent variable corresponding to the display brightness value less than or equal to the first threshold is the pulse width modulation duty cycle; the linear interpolation independent variable corresponding to the display brightness value greater than the first threshold is the display brightness value.

4. The method for driving a display screen according to claim 1, characterized in that: The step of linearly interpolating the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value according to the linear interpolation instruction specifically includes: Calculate the slope k: Wherein, Data1 is the first pixel data voltage value, Data2 is the second pixel data voltage value, Variable1 is the linear interpolation independent variable corresponding to the first display brightness value, and Variable2 is the linear interpolation independent variable corresponding to the second display brightness value; Calculate the difference of the independent variable dVariable: dVariable=Variable-Variable1 Among them, Variable is the linear interpolation independent variable corresponding to the current display brightness value; Calculate the interpolation increment dy: dy=k*dVariable Calculate the difference result Data: Data=Data1+dy Data is the current pixel data voltage value corresponding to the current display brightness value.

5. The method for driving a display screen according to claim 4, characterized in that: The driving method further comprises: storing pixel data voltage values ​​corresponding to different display brightness values ​​in a second lookup table; According to the current display brightness value, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are searched in the second lookup table.

6. The method for driving a display screen according to any one of claims 1 to 5, characterized in that: The driving method further comprises: The current pixel data voltage value obtained by linear interpolation is written into the corresponding register.

7. A driving device for a display screen, characterized in that: include: An input buffer module, used for providing the current display brightness value of the display screen; A control module, configured to determine a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value, and generate a linear interpolation instruction based on the linear interpolation independent variable, wherein the linear interpolation instruction instructs: performing linear interpolation based on the linear interpolation independent variable; A linear interpolation module, configured to perform linear interpolation on a first pixel data voltage value corresponding to a first display brightness value and a second pixel data voltage value corresponding to a second display brightness value according to the linear interpolation instruction, to obtain a current pixel data voltage value corresponding to a current display brightness value; The first display brightness value is smaller than the current display brightness value and is adjacent to the current display brightness value, and the second display brightness value is larger than the current display brightness value and is adjacent to the current display brightness value.

8. The display screen driving device according to claim 7, characterized in that: The driving device further comprises: A storage module, used for storing the mapping relationship between different display brightness values ​​and corresponding linear interpolation independent variables in a first lookup table; The control module is specifically configured to: search the first lookup table for a linear interpolation independent variable corresponding to the current display brightness value according to the current display brightness value.

9. The driving device of a display screen according to claim 8, characterized in that: The first lookup table indicates that: the linear interpolation independent variable corresponding to the display brightness value less than or equal to the first threshold is the pulse width modulation duty cycle; the linear interpolation independent variable corresponding to the display brightness value greater than the first threshold is the display brightness value.

10. The driving device of a display screen according to claim 7, characterized in that: The linear interpolation module is specifically used for: Calculate the slope k: Wherein, Data1 is the first pixel data voltage value, Data2 is the second pixel data voltage value, Variable1 is the linear interpolation independent variable corresponding to the first display brightness value, and Variable2 is the linear interpolation independent variable corresponding to the second display brightness value; Calculate the difference of the independent variable dVariable: dVariable=Variable-Variable1 Among them, Variable is the linear interpolation independent variable corresponding to the current display brightness value; Calculate the interpolation increment dy: dy=k*dVariable Calculate the difference result Data: Data=Data1+dy Data is the current pixel data voltage value corresponding to the current display brightness value.

11. The display screen driving device according to claim 10, characterized in that: The driving device further comprises a storage module, wherein the storage module is used for: storing pixel data voltage values ​​corresponding to different display brightness values ​​in a second lookup table; According to the current display brightness value, the first pixel data voltage value corresponding to the first display brightness value and the second pixel data voltage value corresponding to the second display brightness value are searched in the second lookup table.

12. The driving device of a display screen according to any one of claims 7 to 11, characterized in that: The driving device further comprises: The register output module is used to write the current pixel data voltage value obtained through linear interpolation into the corresponding register.

13. A display device, characterized in that: A driving device for a display screen comprising any one of claims 7 to 12.

14. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the steps of the method for driving a display screen as claimed in any one of claims 1 to 6 are implemented.

15. A readable storage medium, characterized in that: The readable storage medium stores a program or an instruction, and when the program or the instruction is executed by a processor, the method for driving a display screen according to any one of claims 1 to 6 is implemented.

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