A liquid crystal display panel gray scale offset suppression method and display device

Abstract

The application discloses a liquid crystal display panel gray scale offset inhibition method, comprising the following steps: S1, determining a viewing polar angle range; S2, acquiring a voltage-transmittance curve; S3, determining a lowest peak transmittance voltage; S4, re-distributing a gray scale-voltage curve; and S5, implementing gray scale driving. The application also discloses a display device, mainly comprising a viewing polar angle calculation module, an electro-optical curve acquisition module, a voltage discrimination module, a gray scale voltage generation module and a gray scale driving module. The application determines the lowest peak transmittance voltage under each inclined viewing angle, re-distributes the gray scale-voltage curve for driving the liquid crystal display panel, and implements gray scale driving, thereby effectively inhibiting the gray scale offset problem of the liquid crystal display panel under the inclined viewing angle, and improving the picture quality of the liquid crystal display panel under a large viewing angle.

Description

I. TECHNICAL FIELD

[0001] The present application relates to the technical field of display, more particularly, the present application relates to a liquid crystal display panel gray scale offset suppression method and display device. II. BACKGROUND

[0002] Liquid crystal display panels have the advantages of low power consumption, long service life, high cost performance, etc., and are widely used in various large, medium and small size display scenarios. Liquid crystal is an optically anisotropic material with birefringence, that is, there are ordinary light refractive index and extraordinary light refractive index. Due to the birefringence of liquid crystal itself, the liquid crystal display panel has different phase retardation at each viewing angle, and the electro-optic performance at normal view and each inclined view is also different, so the liquid crystal display panel has different degrees of gray scale offset problem at inclined view angle.

[0003] In the prior art, in order to improve the gray scale offset of the liquid crystal display panel at the inclined view angle, methods such as multi-domain electrode structure, multi-box structure, optical scattering film are usually used. However, the above methods have some drawbacks. For example, by designing a multi-domain electrode structure, the optical performance between pixels can be complementary, but it has the disadvantage of increasing the manufacturing difficulty; by designing a multi-box structure, the viewing angle performance can be improved, but it has the disadvantage of increasing the thickness of the display panel; by designing an optical scattering film, the gray scale-voltage curve at each viewing angle can be more uniform, but it has the disadvantage of limiting the resolution. Therefore, a technical method is needed that can suppress the gray scale offset of the liquid crystal display panel at a large viewing angle without increasing the manufacturing difficulty, increasing the thickness of the display panel, and limiting the resolution. III. SUMMARY

[0004] The present application proposes a liquid crystal display panel gray scale offset suppression method and display device to solve the gray scale offset problem of the existing liquid crystal display panel at a large viewing angle.

[0005] The present application proposes a liquid crystal display panel gray scale offset suppression method, which comprises the following steps:

[0006] S1, determine the viewing polar angle range:

[0007] According to the position of the liquid crystal display panel and the viewing position of the human eye, the viewing polar angle range of the liquid crystal display panel is determined; the viewing polar angle range is [0°, θ max ], θ max is the maximum polar angle:

[0008]

[0009] wherein, D is the distance from the human eye to the plane of the liquid crystal display panel, Lis the distance between the farthest pixel of the liquid crystal display panel and the eye viewing position;

[0010] S2, obtaining voltage-transmittance curve:

[0011] obtaining voltage-transmittance curve of the liquid crystal display panel under normal view and each inclined view angle within the viewing polar angle range;

[0012] S3, determining the lowest peak transmittance voltage:

[0013] determining each peak transmittance voltage and the lowest peak transmittance voltage according to the voltage-transmittance curve under normal view and each inclined view angle;

[0014] S4, re-distributing the gray scale-voltage curve:

[0015] in the range of the lowest peak transmittance voltage, mapping according to the gray scale bit number bit and the gray scale index γ of the liquid crystal display panel to re-distribute the gray scale-voltage curve of the liquid crystal display panel, wherein the distribution scheme of the gray scale voltage V is determined by the following formula:

[0016] ,

[0017] wherein, V max is the lowest peak transmittance voltage, L 1 is the gray scale value, bit is the gray scale bit number, γ is the gray scale index;

[0018] S5, implementing gray scale driving:

[0019] implementing gray scale driving on the liquid crystal display panel according to the re-distributed gray scale-voltage curve.

[0020] Further, in the step S1, the normal view and each inclined view angle are determined by polar angle θ and azimuth angle φ , i.e. ( θ , φ ); wherein, the polar angle θ is the spatial angle between the normal of the liquid crystal display panel and the eye viewing line, the azimuth angle φ is the spatial angle between the horizontal direction of the liquid crystal display panel and the eye viewing line, θ ∈[0°, θ max ]、 φ ∈[0°, 360°]; wherein, (0°, 0°) is the normal view angle, and the others are inclined view angles.

[0021] Furthermore, in step S3, the peak transmittance voltage is the voltage corresponding to the peak transmittance at each viewing angle within the viewing polar angle range.

[0022] Furthermore, in step S3, the lowest peak transmittance voltage is the maximum grayscale voltage of the liquid crystal display panel.

[0023] Further, in step S4, within the range of the lowest peak transmittance voltage, i.e. [0, V max Within the range, based on the grayscale bit depth of the liquid crystal display panel. bit and grayscale index γ The mapping is performed to redistribute the grayscale-voltage curve of the LCD panel.

[0024] The present invention also proposes a display device, the device comprising:

[0025] The viewing polar angle calculation module includes a display panel positioning unit, a human eye positioning unit, and a polar angle range calculation unit. This module is used to locate the position of the liquid crystal display panel and the position of the human eye, obtain the distance from the human eye to the plane of the liquid crystal display panel, and the distance from the farthest pixel of the liquid crystal display panel to the human eye's viewing position; and calculate the viewing polar angle range through the polar angle range calculation unit.

[0026] The electro-optic curve acquisition module includes a panel driving unit and a brightness acquisition unit. The module outputs different grayscale voltages through the panel driving unit and acquires voltage-transmittance curves under different grayscale voltages and various tilt angles through the brightness acquisition unit.

[0027] The voltage discrimination module includes a voltage calculation unit and a voltage discrimination unit. The voltage calculation unit calculates the peak transmittance voltage under normal viewing and various tilted viewing angles. The voltage discrimination unit determines the minimum value of each peak transmittance voltage.

[0028] Grayscale voltage generation module; this module can generate grayscale voltage based on the grayscale bit depth of the liquid crystal display panel within the range of the lowest peak transmittance voltage. bit and grayscale index γ Mapping is performed, where grayscale voltage is... V The allocation scheme is determined by the following formula:

[0029] ,

[0030] in, V max It is the voltage at which the light transmittance is lowest. L 1 represents the grayscale value. bit It is the number of gray levels. γ It is the grayscale index;

[0031] reallocate the gray-scale-voltage curve of the liquid crystal display panel according to the distribution scheme of the gray-scale voltage; V

[0032] a gray-scale driving module; the module can drive the liquid crystal display panel according to the reallocated gray-scale-voltage curve.

[0033] Preferably, in the existing liquid crystal display technology, the number of gray-scale bits bit ≥8.

[0034] Preferably, according to the brightness sensitivity index of the human eye, the gray-scale index of the liquid crystal display panel γ is usually 2.0-2.6.

[0035] The present application provides a liquid crystal display panel gray-scale offset suppression method, and the main process of the method is as follows: determining the viewing polar angle range of the liquid crystal display panel according to the position of the liquid crystal display panel and the viewing position of the human eye; obtaining the voltage-transmittance curve and the peak transmittance voltage under different viewing angles; determining the lowest peak transmittance voltage; reallocating the gray-scale-voltage curve in the range of the lowest peak transmittance voltage; and implementing gray-scale driving according to the reallocated gray-scale-voltage curve. In addition, the present application also provides a display device, which comprises a viewing polar angle calculation module, an electro-optical curve acquisition module, a voltage discrimination module, a gray-scale voltage generation module, and a gray-scale driving module, and the device can realize the modulation of the gray-scale offset of the liquid crystal display panel. Compared with the prior art, the method and the display device provided by the present application make the gray-scale-transmittance curves of the liquid crystal display panel under different viewing angles tend to be the same, and implement gray-scale driving, thereby effectively suppressing the gray-scale offset under the inclined viewing angle and improving the picture quality of the liquid crystal display panel under large viewing angles. IV. BRIEF DESCRIPTION OF DRAWINGS

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings used in the embodiments of the present application are described as necessary.

[0037] Figure 1 FIG. 1 is a flowchart of the liquid crystal display panel gray-scale offset suppression method according to the present application.

[0038] Figure 2 FIG. 2 is a schematic diagram of the display device according to the present application.

[0039] Figure 3 FIG. 3 is the voltage-transmittance curve under different viewing angles in the embodiments of the present application.

[0040] Figure 4 FIG. 4 is the gray-scale-transmittance curve not using the present application in the embodiments of the present application.

[0041] Figure 5 FIG. 5 is the original gray-scale-voltage curve and the reallocated gray-scale-voltage curve in the embodiments of the present application.​

[0042] Figure 6 The gray scale-transmittance curve after using the present application in the embodiment of the present application. V. DETAILED DESCRIPTION

[0043] The present application will be described in detail below with reference to the drawings and specific embodiments. It is necessary to point out that the following embodiments are only used for further description of the present application and cannot be understood as a limitation on the protection scope of the present application. Non-essential modifications proposed by the person skilled in the art on the basis of the present application all belong to the protection scope of the present application.

[0044] The embodiment provides a liquid crystal display panel gray scale offset suppression method, and a flowchart of the method is shown in Figure 1 , mainly comprising:

[0045] S1, determining a viewing polar angle range:

[0046] According to the position of the liquid crystal display panel and the viewing position of the human eye, the viewing polar angle range of the liquid crystal display panel is determined; the viewing polar angle range is [0°, θ max ], θ max is the maximum polar angle:

[0047]

[0048] wherein, D is the distance from the human eye to the plane of the liquid crystal display panel, L is the distance from the farthest pixel of the liquid crystal display panel to the viewing position of the human eye;

[0049] S2, obtaining a voltage-transmittance curve:

[0050] Obtaining the voltage-transmittance curve of the liquid crystal display panel under the orthovision and each oblique viewing angle in the viewing polar angle range;

[0051] S3, determining a lowest peak transmittance voltage:

[0052] According to the voltage-transmittance curve under the orthovision and each oblique viewing angle, the peak transmittance voltage and the lowest peak transmittance voltage are determined;

[0053] S4, re-distributing a gray scale-voltage curve:

[0054] In the range of the lowest peak transmittance voltage, the gray scale-voltage curve of the liquid crystal display panel is re-distributed according to the gray scale bit number bit and the gray scale index γ , wherein the distribution scheme of the gray scale voltage V is determined by the following formula:

[0055] ,

[0056] wherein, V max is the lowest peak transmittance voltage, L 1 is a gray value, bit is a gray bit number, γ is a gray index;

[0057] S5, implementing gray driving:

[0058] According to the re-distributed gray-voltage curve, the liquid crystal display panel is implemented gray driving.

[0059] In addition, the embodiment provides a display device, a schematic diagram of which is as shown in Figure 2 , mainly comprising:

[0060] The viewing polar angle calculation module comprises a display panel positioning unit, a human eye positioning unit and a polar angle range calculation unit; the module is used for calculating the viewing polar angle range;

[0061] The electro-optic curve acquisition module comprises a panel driving unit and a luminance acquisition unit; the module is used for acquiring the voltage-transmittance curve under normal view and each inclined viewing angle under different gray voltages;

[0062] The voltage discrimination module comprises a voltage calculation unit and a voltage discrimination unit; the module is used for discriminating the lowest value of the peak transmittance voltage under each viewing angle;

[0063] The gray voltage generation module; the module is used for mapping according to the gray bit number bit and the gray index γ of the liquid crystal display panel within the range of the lowest peak transmittance voltage, wherein the distribution scheme of the gray voltage V is determined by the following formula:

[0064] ,

[0065] wherein, V max is the lowest peak transmittance voltage, L 1 is a gray value, bit is a gray bit number, γ is a gray index;

[0066] The gray-voltage curve of the liquid crystal display panel is re-distributed according to the distribution scheme of the gray voltage V ;

[0067] The gray driving module; the module is used for implementing gray driving on the liquid crystal display panel.

[0068] In this embodiment, the grayscale depth of a liquid crystal display panel is... bit =10, there are 1024 gray levels from 0 to 1023, gray level index. γ =2.2; The parameters for the position of the liquid crystal display panel and the viewing position of the human eye are: the distance from the human eye to the plane of the liquid crystal display panel. D =3m, the distance between the farthest pixel of the LCD panel and the viewing position of the human eye. L =6m.

[0069] The process for suppressing grayscale shift in the liquid crystal display panel in this embodiment is as follows:

[0070] The first step is to determine the viewing angle range of the LCD panel as [0°, 60°] based on the position of the LCD panel and the viewing position of the human eye.

[0071] The second step involves using an electro-optic curve acquisition module to obtain the voltage-transmittance curves of the liquid crystal display panel under normal viewing and various tilted viewing angles within the viewing polar angle range. The specific implementation method is as follows: First, within the viewing angle range, multiple azimuth angles are sampled. φ The voltage-transmittance curves are obtained at each viewing angle. Then, for each viewing angle, the liquid crystal display panel is driven within a voltage range of 0-10V, and the corresponding transmittance is measured. Finally, based on the measurement results, the voltage-transmittance curves at each viewing angle are obtained. Figure 3 The voltage-transmittance curves are shown for both frontal viewing and at a 60° polar angle.

[0072] The third step involves using a voltage discrimination module to determine the lowest peak transmittance voltage at each viewing angle; this is achieved through comparison. Figure 3 The voltage-transmittance curve shown indicates that the minimum peak transmittance voltage is 4.2V, and its corresponding viewing angle is ( θ , φ (60°, 90°); if the minimum peak transmittance voltage is uncertain, and the LCD panel is still driven using the traditional method, the corresponding grayscale shift will be severe, and grayscale inversion will occur within the large grayscale value range, such as... Figure 4 As shown;

[0073] The fourth step involves using a grayscale voltage generation module to determine the number of grayscale levels within the range of the lowest peak transmittance voltage (4.2V). bit =10 corresponds to the 0th to 1023rd gray levels according to the gray level index. γ =2.2 Perform mapping and redistribute the grayscale-voltage curve, i.e.:

[0074] ,

[0075] The original grayscale-voltage curve and the redistributed grayscale-voltage curve are as follows: Figure 5 As shown;

[0076] In the fifth step, the gray scale driving module is used to drive the liquid crystal display panel according to the re-distributed gray scale-voltage curve.

[0077] Figure 6 is the gray scale-transmittance curve of the liquid crystal display panel after using the present application. Compared with Figure 4 As can be seen, the gray scale-transmittance curve of the liquid crystal display panel under each inclined viewing angle becomes closer, the gray scale inversion phenomenon is eliminated, and the gray scale shift is effectively inhibited. The present application is an effective method for inhibiting the gray scale shift of the liquid crystal display panel under large viewing angles without increasing the manufacturing difficulty, the thickness of the display panel, and the resolution.

[0078] The above examples are only used to illustrate the technical solutions of the present application, and are not used to limit the present application. Any non-essential modification, equivalent replacement or improvement made by those skilled in the art under the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for suppressing gray scale shift of a liquid crystal display panel, characterized by, The method comprises the following steps: S1, determining a viewing polar angle range: According to the liquid crystal display panel position and the human eye watching position, a viewing polar angle range of the liquid crystal display panel is determined; the viewing polar angle range is [0°, θ max ], θ max is the maximum polar angle wherein, D is the distance from the human eye to the plane of the liquid crystal display panel, L is the distance from the farthest pixel of the liquid crystal display panel to the position of the human eye to view; S2, acquiring a voltage-transmittance curve: acquiring a voltage-transmittance curve of the liquid crystal display panel under a normal view and each inclined view within the viewing polar angle range; S3, determining a lowest peak transmittance voltage: determining a voltage corresponding to each peak transmittance and the lowest peak transmittance voltage according to the voltage-transmittance curve under the normal view and each inclined view; S4, re-distributing a gray scale-voltage curve: In the range of the lowest peak transmittance voltage, the gray scale-voltage curve of the liquid crystal display panel is redistributed according to the gray scale bit number bit and the gray scale index γ of the liquid crystal display panel, wherein the distribution scheme of the gray scale voltage V is determined by the following formula: ， wherein, V max is the lowest peak transmittance voltage, L 1 is a gray scale value, bit is the number of gray scale bits, γ is the gray scale index; S5, implementing gray scale driving: implementing gray scale driving on the liquid crystal display panel according to the re-distributed gray scale-voltage curve.

2. The method of claim 1, wherein the method is characterized by: The normal view and each inclined view angle are determined by polar angle θ and azimuth angle φ , that is, θ , φ ); wherein, polar angle θ is the spatial angle between the normal of the liquid crystal display panel and the line of sight of the human eye, and azimuth angle φ is the spatial angle between the horizontal direction of the liquid crystal display panel and the line of sight of the human eye, θ ∈[0°, θ max ]、 φ ∈[0°, 360°]; wherein, (0°, 0°) is the normal view angle, and the others are inclined view angles.

3. The method of claim 1, wherein the method is characterized by: The lowest peak transmittance voltage is a maximum gray scale voltage of the liquid crystal display panel, and after the gray scale-voltage curve is re-distributed, the liquid crystal display panel is driven in the range of the lowest peak transmittance voltage.

4. A display device, characterized by comprising: The display device comprises: a viewing polar angle calculation module (100) comprising a display panel positioning unit (110), a human eye positioning unit (120) and a polar angle range calculation unit (130); the display panel positioning unit and the human eye positioning unit are used to respectively position a position of a liquid crystal display panel and a position of a human eye, to acquire a distance from the human eye to a plane of the liquid crystal display panel and a distance from a farthest pixel of the liquid crystal display panel to a viewing position of the human eye; the polar angle range calculation unit is used to calculate a viewing polar angle range; an electro-optic curve acquisition module (200) comprising a panel driving unit (210) and a brightness acquisition unit (220); the panel driving unit is used to output different gray scale voltages; the brightness acquisition unit is used to acquire a voltage-transmittance curve under a normal view and each inclined view under different gray scale voltages; a voltage discrimination module (300) comprising a voltage calculation unit (310) and a voltage discrimination unit (320); the voltage calculation unit is used to calculate a peak transmittance voltage under the normal view and each inclined view; the voltage discrimination unit is used to discriminate a lowest value of each peak transmittance voltage; The gray-scale voltage generation module (400) maps the gray-scale index and the gray-scale voltage according to the gray-scale bit number of the liquid crystal display panel within the range of the minimum peak transmittance voltage bit and the gray-scale index γ , wherein the allocation scheme of the gray-scale voltage V is determined by the following formula: ， wherein, V max is the lowest peak transmittance voltage, L 1 is a gray scale value, bit is the number of gray scale bits, γ is a gray scale index; According to grayscale voltage V The allocation scheme redistributes the grayscale-voltage curve of the liquid crystal display panel; a gray scale driving module (500) used to drive the liquid crystal display panel according to the re-distributed gray scale-voltage curve.

Images