Liquid crystal display device and method for improving low-view-angle bluish violet and ground color partial transmission

Abstract

The invention discloses a liquid crystal display device and method for improving low-view-angle bluish violet and ground color partial transmission. The liquid crystal display device comprises an upper polaroid, a liquid crystal box, a lower polaroid and a backlight module which are sequentially arranged in a stacked mode. The liquid crystal box is a vertical alignment type liquid crystal box, and the box thickness of a liquid crystal layer in the liquid crystal box is 3.2-3.8 microns; the upper polaroid and the lower polaroid adopt a combination of wide-view-angle low-color-offset polaroids; a light condensation type brightness enhancement film layer is arranged in the backlight module and used for gathering light around backlight to the center of a display area so as to compensate optical path difference unbalance caused by inclination of liquid crystal molecules at a low visual angle. According to the invention, through a collaborative system of box thickness optimization, polaroid adaptation and brightness enhancement film light field regulation and control, low-view-angle background color partial transmission and blue violet of the VA-type LCD are eliminated, the process yield is considered, and the advantage of high contrast ratio of the VA-type LCD is maintained.

Description

Technical Field

[0001] This invention relates to the field of liquid crystal display technology, and in particular to a liquid crystal display device and method for improving low-viewing-angle bluish-purple tint and background color translucency. Background Technology

[0002] Liquid crystal displays (LCDs) are currently the mainstream flat panel display devices. Among them, vertically aligned (VA / MAV) LCDs, with their core advantages of high contrast, low dark-state light leakage, and good color reproduction, are widely used in scenarios with high display quality requirements, such as automotive displays, industrial control, and high-end consumer electronics. However, due to the inherent characteristics of the vertical alignment of liquid crystal molecules, VA / MAV LCDs are limited when viewed at low angles. The tilt of the liquid crystal molecules causes an imbalance in optical path difference, resulting in a background color translucency and a bluish-purple tint to the displayed image. This severely degrades the display contrast and viewing effect at low angles, becoming a core technical bottleneck restricting the large-scale application of VA / MAV LCDs in all-viewing-angle display scenarios.

[0003] CN108287422A discloses an irregularly shaped liquid crystal display screen, which adopts a structure of sequentially stacked surface polarizer, liquid crystal cell, bottom polarizer and backlight plate. By using an ultra-thin ITO glass substrate to improve the light transmittance of the device, adding an optical compensation film to the bottom polarizer to widen the conventional viewing angle, and setting a combination of a reflective polarizing brightness enhancement film and an ultra-micro polycrystalline structure brightness enhancement film in the backlight plate to improve the overall brightness of the backlight, the display screen achieves high light transmittance, high contrast and wide viewing angle performance optimization.

[0004] CN108227282A discloses a high-uniformity thin liquid crystal display screen. Based on the above-mentioned stacked structure, it further precisely controls the thickness parameters of the brightness enhancement film, increases the distance between the edge of the light guide plate and the TFTAA area to reduce edge reflection, and improves the stability of the liquid crystal cell structure by adding a PS support structure to the BM area through photo-alignment process. It aims to solve the defects of poor uniformity and large device thickness in traditional LCDs and achieve high uniformity, thinness and wide viewing angle of the display screen.

[0005] The aforementioned existing technologies have the following core defects and limitations, and cannot solve the technical problems of low-viewing-angle background color translucency and bluish-purple tint in VA / MAV type LCDs: First, the aforementioned existing technologies are all optimized for the general performance (transmittance, screen uniformity, overall device thickness, and conventional wide viewing angle characteristics) of general TFT LCDs or irregularly shaped screens. They do not pay attention to the unique problems of low viewing angle background color translucency and bluish-purple tint caused by the inherent characteristics of vertical alignment of liquid crystal molecules in VA / MAV LCDs, nor do they address the core causes of these problems with corresponding technical designs. Therefore, they cannot fundamentally improve these display defects.

[0006] Secondly, the wide viewing angle optimization of the aforementioned existing technologies only improves the brightness and contrast within the normal viewing angle range through optical compensation films and brightness enhancement films. It cannot suppress color shift and background color transparency issues at low viewing angles, and its effect on improving the low viewing angle display defects of VA / MAV type LCDs is extremely limited.

[0007] In summary, current technologies have not yet proposed a technical solution to effectively solve the problems of background color translucency and bluish-purple tint at low viewing angles in VA / MAV type LCDs. They cannot improve the display effect at low viewing angles while ensuring the original performance advantages of VA / MAV type LCDs. Therefore, it is urgent to develop corresponding technical solutions to fill the gaps in existing technologies and meet the application needs of VA / MAV type LCDs in full-view display scenarios. Summary of the Invention

[0008] The technical problem to be solved by the present invention is to provide a liquid crystal display device and method for improving low-viewing-angle blue-purple tint and background color translucency. It can eliminate low-viewing-angle background color translucency and blue-purple tint of VA type LCD through a synergistic system of cell thickness optimization, polarizer adaptation and brightness enhancement film light field control, while taking into account process yield and retaining its high contrast advantage.

[0009] In order to solve the above-mentioned technical problems, the first aspect of the present invention discloses a VA / MAV type liquid crystal display device that improves low-viewing-angle bluish-purple tint and background color translucency, comprising an upper polarizer, a liquid crystal cell, a lower polarizer and a backlight module arranged in sequence. The liquid crystal cell is a vertically aligned liquid crystal cell, and the cell thickness of the liquid crystal layer inside the liquid crystal cell is 3.2μm~3.8μm; The upper polarizer and the lower polarizer are a combination of wide-viewing-angle, low-color polarizers; The backlight module is provided with a light-concentrating brightness enhancement film layer, which is used to concentrate the light from the surrounding area of ​​the backlight towards the center of the display area to compensate for the optical path difference imbalance caused by the tilt of liquid crystal molecules at low viewing angles.

[0010] As an optional implementation, in the first aspect of the present invention, the pixel unit of the liquid crystal cell adopts a multi-domain segmentation structure, and a single pixel unit is divided into multiple sub-regions. The liquid crystal molecules in each sub-region are oriented in different preset directions when energized, and the light characteristics of different sub-regions are complementary at oblique viewing angles.

[0011] As another alternative implementation, in the first aspect of the invention, the cell thickness of the liquid crystal layer is 3.5 μm.

[0012] As another optional implementation, in the first aspect of the present invention, the light-concentrating brightness enhancement film layer is a prism-type brightness enhancement film, wherein the light-concentrating surface of the prism-type brightness enhancement film is disposed facing the liquid crystal cell side.

[0013] As another optional implementation, in the first aspect of the present invention, the luminance gain coefficient of the prism-type brightness enhancement film is 1.55 to 1.90.

[0014] As another optional implementation, in the first aspect of the present invention, the applicable temperature range of the wide-viewing-angle low-color-polarization polarizer combination is -40℃ to 80℃, and the background color of the side viewing angle is black.

[0015] The second aspect of this invention discloses a method for improving the low-viewing-angle bluish-purple tint and background color translucency of VA / MAV type LCDs, comprising the following steps: S1. Cell thickness adjustment: Adjust the cell thickness of the liquid crystal layer of the VA / MAV type vertically aligned liquid crystal cell to 3.2μm~3.8μm to reduce the optical path difference fluctuation caused by the tilt of liquid crystal molecules at low viewing angles; S2. Polarizing film adapter: Select a wide-viewing-angle, low-color-polarization polarizing film combination that matches the adjusted cell thickness parameters, and attach it to the light-emitting side and the light-receiving side of the liquid crystal cell respectively. S3. Light field control: A light-concentrating brightness enhancement film layer is added to the backlight module. The light-concentrating brightness enhancement film layer concentrates the light from the surrounding area of ​​the backlight towards the center of the display area, compensating for the imbalance of optical path difference at low viewing angles and eliminating the background color translucency and bluish-purple phenomenon at low viewing angles.

[0016] As an optional implementation, in the second aspect of the present invention, in step S3, the light-concentrating brightness enhancement film layer is a prism-type brightness enhancement film, and the light-concentrating surface of the prism-type brightness enhancement film is facing the liquid crystal cell side during setting, and the brightness gain coefficient of the prism-type brightness enhancement film is controlled to be 1.55~1.90.

[0017] As another optional implementation, the second aspect of the present invention further includes a pixel structure optimization step: performing multi-domain segmentation on the pixel unit of the liquid crystal cell, dividing a single pixel unit into multiple sub-regions, so that the liquid crystal molecules in each sub-region face different preset directions when energized, and offsetting the color shift under the oblique viewing angle through the complementary light characteristics of different sub-regions.

[0018] As another optional implementation, in the second aspect of the present invention, in step S1, the cell thickness of the liquid crystal layer of the VA / MAV type liquid crystal cell is precisely adjusted to 3.5 μm.

[0019] The third aspect of the present invention discloses an apparatus for improving the low viewing angle bluish-purple tint and background translucency of VA / MAV type LCDs, comprising a memory, a processor, and a computer program stored in the memory, wherein the processor executes the computer program to implement the steps of the method disclosed in the second aspect of the present invention.

[0020] The fourth aspect of the present invention discloses a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method disclosed in the second aspect of the present invention.

[0021] Compared with the prior art, the embodiments of the present invention have the following beneficial effects: Compared to existing technologies, this invention addresses the core cause of low-viewing-angle background color distortion and bluish-purple tint in VA-type LCDs (optical path difference imbalance caused by liquid crystal molecule tilt at low viewing angles). It constructs a synergistic improvement system of "cell thickness optimization - polarizer adaptation - brightness enhancement film light field modulation." Experimental verification shows that this system can completely eliminate background color distortion and bluish-purple tint at low viewing angles in VA-type LCDs, solving the common low-viewing-angle display degradation problem in existing similar products. The cell thickness is limited to 3.2μm~3.8μm, effectively reducing optical path difference fluctuations caused by liquid crystal molecule tilt at low viewing angles, reducing color shift sources at the liquid crystal cell level, and avoiding poor liquid crystal alignment and decreased process yield caused by excessively thin cell thickness, as well as issues caused by excessively thick cell thickness. The invention addresses the dual defects of increased optical path difference fluctuations and worsened color shift caused by large backlight angles. This invention overcomes the limitation of existing brightness enhancement films, which are only used to improve front brightness. By controlling the light field of the light-concentrating brightness enhancement film layer, it focuses light emitted from the periphery of the backlight at large angles towards the display center, directly compensating for the optical path difference imbalance at low viewing angles. This achieves targeted improvement of color shift at low viewing angles from the backlight level, rather than simply increasing brightness. The combination of a wide-viewing-angle, low-color-shift polarizer and the above two technologies creates a synergistic effect, further suppressing color shift at oblique viewing angles. The three technologies work together to comprehensively improve low-viewing-angle display defects while fully preserving the core performance advantages of high contrast and low dark-state light leakage inherent in VA-type LCDs. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the structure of a VA / MAV type liquid crystal display device that improves low-viewing-angle bluish-purple tint and background color translucency, as disclosed in an embodiment of the present invention. Figure 2 This is a flowchart illustrating a method for improving the low-viewing-angle bluish-purple tint and background translucency of VA / MAV type LCDs, as disclosed in an embodiment of the present invention. Figure 3 This is a schematic diagram of the structure of a device disclosed in an embodiment of the present invention for improving the low-viewing-angle bluish-purple tint and background color translucency of VA / MAV type LCDs. Detailed Implementation

[0024] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1 See Figure 1 The present invention discloses a VA / MAV type liquid crystal display device for improving low-viewing-angle bluish-purple tint and background color translucency, comprising an upper polarizer 1, a liquid crystal cell 2, a lower polarizer 3 and a backlight module 4 stacked in sequence. The liquid crystal cell 2 is a vertically aligned liquid crystal cell 2, and the cell thickness of the liquid crystal layer inside the liquid crystal cell 2 is 3.2μm~3.8μm; The upper polarizer 1 and the lower polarizer 3 are a combination of wide-viewing-angle, low-color polarizers; The backlight module 4 is provided with a light-concentrating brightness enhancement film layer 41, which is used to concentrate the light from the surrounding area of ​​the backlight towards the center of the display area to compensate for the optical path difference imbalance caused by the tilt of liquid crystal molecules at low viewing angles.

[0026] This embodiment is applicable to VA / MAV type vertical alignment liquid crystal displays, and is not applicable to LCD products of other alignment types such as TN and IPS. The light propagation logic of the stacked structure is as follows: the backlight module 4 is the only light source. After the light is emitted from the backlight module 4, it passes through the lower polarizer 3, the liquid crystal cell 2, and the upper polarizer 1 in sequence before being emitted to the human eye. The upper polarizer 1 is attached to the light-emitting side (the side observed by the human eye) of the liquid crystal cell 2, and the lower polarizer 3 is attached to the light-incident side (the side of the backlight module 4) of the liquid crystal cell 2. The light-concentrating brightness enhancement film layer 41 is disposed in the backlight module 4 and on the light-incident side of the lower polarizer 3. Experimental verification shows that adjusting the cell thickness alone or replacing the polarizer alone cannot completely eliminate the problems of low viewing angle bluish-purple tint and background color translucency. The best improvement effect can be achieved by the cooperation of all three.

[0027] This invention addresses the root cause of color shift in VA / MAV type LCDs—optical path difference imbalance due to liquid crystal molecule tilt at low viewing angles. It employs a three-parameter synergistic scheme: cell thickness optimization, low-color-bias polarizer matching, and light field modulation of a focusing brightness enhancement film layer. This systematically improves the issues of background color distortion and bluish-purple tint at low viewing angles. Experimental verification shows that the optimized sample exhibits no significant background color distortion or bluish-purple tint at low viewing angles, achieving the preset display effect target. This overcomes the functional limitation of existing brightness enhancement films, which are only used to improve backlight brightness. The light-concentrating brightening film layer 41 concentrates the large-angle light from all sides of the backlight towards the center of the display area, directly compensating for the optical path difference imbalance under low viewing angles, thus solving the color shift problem at its root. At the same time, it does not require any radical changes to the LCD basic architecture and is fully compatible with existing mature production processes. The cell thickness is limited to the range of 3.2μm~3.8μm, which can effectively reduce the optical path difference fluctuation caused by the tilt of liquid crystal molecules under low viewing angles, providing a basis for color shift improvement, while avoiding process risks such as abnormal liquid crystal response speed and reduced production yield caused by excessively small cell thickness.

[0028] Optionally, the backlight module is a direct-lit or edge-lit backlight module of a VA / MAV type LCD. The light-concentrating brightness enhancement film layer 41 is disposed at the top of the light-emitting side of the backlight module, located between the diffusion film of the backlight module and the lower polarizer of the liquid crystal cell. The light-incident surface of the light-concentrating brightness enhancement film layer 41 faces the light guide plate side of the backlight module, and the light-emitting surface faces the lower polarizer side of the liquid crystal cell.

[0029] In an optional embodiment, the pixel unit of the liquid crystal cell 2 adopts a multi-domain segmentation structure, in which a single pixel unit is divided into multiple sub-regions. The liquid crystal molecules in each sub-region face different preset directions when energized, and the light characteristics of different sub-regions complement each other at an oblique viewing angle.

[0030] This embodiment uses a pixel multi-domain segmentation design to make the liquid crystal molecules in different sub-regions within a single pixel face different preset directions after being energized. The light characteristics of different sub-regions can complement each other at oblique viewing angles, further offsetting low-viewing-angle color bias and improving the uniformity of display across the entire viewing angle. Combined with the three-parameter synergistic solution, it forms a superimposed improvement effect, which can further reduce the dependence on the light-gathering performance of the brightness enhancement film and adapt to product scenarios with different brightness requirements.

[0031] In another optional embodiment, the cell thickness of the liquid crystal layer is 3.5 μm. In this embodiment, 3.5 μm is the optimal cell thickness parameter verified by experiments. Compared with the standard cell thickness of 4.0 μm, it can effectively reduce the optical path difference fluctuation of liquid crystal molecules tilting at low viewing angles, while taking into account liquid crystal response speed, contrast ratio and production yield. It is the optimal balance point between color shift improvement effect and overall product performance. This cell thickness parameter can form an optimal fit with the wide viewing angle low color shift polarizer and the light-concentrating brightness enhancement film layer 41, further improving the color shift improvement effect at low viewing angles.

[0032] In another optional embodiment, the light-concentrating brightness enhancement film layer 41 is a prism-type brightness enhancement film, with the light-concentrating surface of the prism-type brightness enhancement film facing the liquid crystal cell 2. Using a prism-type brightness enhancement film as the light-concentrating brightness enhancement film layer 41 allows for efficient focusing of large-angle light rays from the periphery of the backlight towards the vertical direction of the display area through the refraction effect of the prism structure. This precisely compensates for the optical path difference imbalance at low viewing angles. Experiments have verified that this structure can completely eliminate background color distortion and bluish-purple tint at low viewing angles. The fact that the light-concentrating surface faces the liquid crystal cell 2 maximizes the light-concentrating effect of the prism structure, reduces light loss, and avoids manufacturing defects such as scratches and Newton's rings caused by contact between the prism structure and other film materials within the backlight module 4.

[0033] In another optional embodiment, the luminance gain coefficient of the prism-type brightness enhancement film is 1.55~1.90. This luminance gain coefficient range is an effective range verified by experiments, which can improve low-viewing angle bias while taking into account the front brightness of the product, avoiding excessively low front brightness due to light focusing, and meeting the display specifications of the product; this range covers the conventional parameters of mainstream commercial brightness enhancement films on the market, allowing for flexible selection based on the product's brightness requirements and cost budget, and has strong scene adaptability.

[0034] In another optional embodiment, the wide-viewing-angle, low-color-polarization polarizer combination has an applicable temperature range of -40℃ to 80℃, and the side-view background color is black. Using a polarizer combination with a black side-view background color can directly suppress blue-violet polarization at low viewing angles from an optical perspective, creating a synergistic effect with cell thickness optimization and brightness enhancement film focusing compensation, further improving the purity of the background color at low viewing angles. The wide temperature range of -40℃ to 80℃ ensures stable polarization performance of the product in extreme high and low temperature environments, avoiding increased color shift due to temperature changes, and is suitable for wide-temperature application scenarios such as automotive and industrial control.

[0035] Example 2 See Figure 2 This invention discloses a method for improving the low-viewing-angle bluish-purple tint and background color translucency of VA / MAV type LCDs, comprising the following steps: S1. Cell thickness adjustment: Adjust the cell thickness of the liquid crystal layer of the VA / MAV type vertically aligned liquid crystal cell to 3.2μm~3.8μm to reduce the optical path difference fluctuation caused by the tilt of liquid crystal molecules at low viewing angles.

[0036] S2. Polarizer adapter: Select a wide-viewing-angle, low-color-polarization polarizer combination that matches the adjusted cell thickness parameters, and attach it to the light-emitting side and the light-receiving side of the liquid crystal cell respectively.

[0037] S3. Light field control: A light-concentrating brightness enhancement film layer is added to the backlight module. The light-concentrating brightness enhancement film layer concentrates the light from the surrounding area of ​​the backlight towards the center of the display area, compensating for the imbalance of optical path difference at low viewing angles and eliminating the background color translucency and bluish-purple phenomenon at low viewing angles.

[0038] This invention addresses the root cause of color shift in VA / MAV type LCDs—optical path difference imbalance caused by liquid crystal molecule tilt at low viewing angles. It employs a three-step progressive synergistic solution—cell thickness adjustment, polarizer adaptation, and light field modulation—to systematically resolve issues of background color distortion and bluish-purple tint at low viewing angles. It overcomes the limitation of existing brightness enhancement films, which are only used to improve backlight brightness. The light field modulation step concentrates large-angle light from the periphery of the backlight towards the center of the display area, directly compensating for the optical path difference imbalance at low viewing angles and fundamentally improving color shift. Furthermore, this method requires no disruptive changes to existing LCD manufacturing processes, is fully compatible with mature mass production lines, and has high mass production feasibility. The cell thickness adjustment step reduces optical path difference fluctuations at low viewing angles from the source, providing a foundation for color shift improvement. The cell thickness range of 3.2μm to 3.8μm avoids process risks such as abnormal liquid crystal response speed and decreased production yield caused by excessively small cell thicknesses, balancing color shift improvement with overall product performance and mass production stability.

[0039] In an optional embodiment, the light-concentrating brightness enhancement film layer is a prism-type brightness enhancement film, with the light-concentrating surface of the prism-type brightness enhancement film facing the liquid crystal cell side during installation, and the brightness gain coefficient of the prism-type brightness enhancement film is controlled to be 1.55~1.90.

[0040] In another optional embodiment, a pixel structure optimization step is also included: multi-domain segmentation of the pixel unit of the liquid crystal cell, dividing a single pixel unit into multiple sub-regions, so that the liquid crystal molecules in each sub-region face different preset directions when energized, and the color shift under the oblique viewing angle is offset by the complementary light characteristics of different sub-regions.

[0041] In another optional embodiment, in step S1, the cell thickness of the liquid crystal layer of the VA / MAV type liquid crystal cell is precisely adjusted to 3.5μm.

[0042] In another optional embodiment, in step S2, the wide-viewing-angle low-color-polarization film combination is applicable to a temperature range of -40℃ to 80℃, and the side-viewing-angle background color is black.

[0043] Example 3 Please see Figure 3 , Figure 3This is a schematic diagram of a device for improving low-viewing-angle bluish-purple tint and background translucency of VA / MAV type LCDs, disclosed in an embodiment of the present invention. It includes a memory 201, a processor 202, and a computer program stored in the memory. The processor executes the computer program to implement the steps in the method disclosed in Embodiment 2.

[0044] Example 4 This invention discloses a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the steps of the method disclosed in Embodiment 2.

[0045] The content disclosed in the embodiments of this invention is only a preferred embodiment of the invention and is used only to illustrate the technical solutions of the invention, not to limit it. Although the invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this invention.

Claims

1. A VA / MAV type liquid crystal display device for improving low-viewing-angle bluish-purple tint and background color translucency, characterized in that, It includes an upper polarizer, a liquid crystal cell, a lower polarizer, and a backlight module, which are stacked in sequence. The liquid crystal cell is a vertically aligned liquid crystal cell, and the cell thickness of the liquid crystal layer inside the liquid crystal cell is 3.2μm~3.8μm; The upper polarizer and the lower polarizer are a combination of wide-viewing-angle, low-color polarizers; The backlight module is provided with a light-concentrating brightness enhancement film layer, which is used to concentrate the light from the surrounding area of ​​the backlight towards the center of the display area to compensate for the optical path difference imbalance caused by the tilt of liquid crystal molecules at low viewing angles.

2. The VA / MAV type liquid crystal display device according to claim 1, characterized in that, The pixel unit of the liquid crystal cell adopts a multi-domain segmentation structure. A single pixel unit is divided into multiple sub-regions. The liquid crystal molecules in each sub-region face different preset directions when energized. The light characteristics of different sub-regions complement each other at oblique viewing angles.

3. The VA / MAV type liquid crystal display device according to claim 1, characterized in that, The cell thickness of the liquid crystal layer is 3.5 μm.

4. The VA / MAV type liquid crystal display device according to claim 1, characterized in that, The light-concentrating brightness enhancement film is a prism-type brightness enhancement film, with the light-concentrating surface of the prism-type brightness enhancement film facing the side of the liquid crystal cell.

5. The VA / MAV type liquid crystal display device according to claim 4, characterized in that, The luminance gain coefficient of the prism-type brightness enhancement film is 1.55~1.

90.

6. The VA / MAV type liquid crystal display device according to claim 1, characterized in that, The wide-viewing-angle, low-color-polarization polarizer combination is applicable to temperatures ranging from -40℃ to 80℃, and has a black background color when viewed from the side.

7. A method for improving the low-viewing-angle bluish-purple tint and background translucency of VA / MAV type LCDs, characterized in that, Includes the following steps: S1. Cell thickness adjustment: Adjust the cell thickness of the liquid crystal layer of the VA / MAV type vertically aligned liquid crystal cell to 3.2μm~3.8μm to reduce the optical path difference fluctuation caused by the tilt of liquid crystal molecules at low viewing angles; S2. Polarizing film adapter: Select a wide-viewing-angle, low-color-polarization polarizing film combination that matches the adjusted cell thickness parameters, and attach it to the light-emitting side and the light-receiving side of the liquid crystal cell respectively. S3. Light field control: A light-concentrating brightness enhancement film layer is added to the backlight module. The light-concentrating brightness enhancement film layer concentrates the light from the surrounding area of ​​the backlight towards the center of the display area, compensating for the imbalance of optical path difference at low viewing angles and eliminating the background color translucency and bluish-purple phenomenon at low viewing angles.

8. The method according to claim 7, characterized in that, In step S3, the light-concentrating brightness enhancement film layer is a prism-type brightness enhancement film. When setting it, the light-concentrating surface of the prism-type brightness enhancement film faces the liquid crystal cell side, and the brightness gain coefficient of the prism-type brightness enhancement film is controlled to be 1.55~1.

90.

9. The method according to claim 7, characterized in that, It also includes a pixel structure optimization step: multi-domain segmentation of the pixel unit of the liquid crystal cell, dividing a single pixel unit into multiple sub-regions, so that the liquid crystal molecules in each sub-region face different preset directions when energized, and the color shift under oblique viewing angle is offset by the complementary light characteristics of different sub-regions.

10. The method according to claim 7, characterized in that, In step S1, the thickness of the liquid crystal layer in the VA / MAV type liquid crystal cell is precisely adjusted to 3.5μm.

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