WO2020087582A1

WO2020087582A1 - Multi-domain liquid crystal display

Info

Publication number: WO2020087582A1
Application number: PCT/CN2018/116022
Authority: WO
Inventors: 陈黎暄
Original assignee: 深圳市华星光电技术有限公司
Priority date: 2018-10-29
Filing date: 2018-11-16
Publication date: 2020-05-07
Also published as: CN109283756B; CN109283756A

Abstract

Disclosed is a multi-domain liquid crystal display, comprising an LCD panel (1), an incident-side polarizer (2) and an emergent-side polarizer (3). The LCD panel (1) comprises multiple pixel structures (5) arranged in an array, wherein each pixel structure (5) comprises at least two sub-pixels (10) which respectively correspond to different colors, each sub-pixel (10) is divided into at least four domain areas (15), each domain area (15) comprises multiple branch electrodes (16) which are parallel to each other and distributed at intervals, and included angles (θ) between the branch electrodes (16) of the at least two sub-pixels (10) which respectively correspond to different colors and a transmission axis of the incident-side polarizer (2) are different. Compared with the prior art, on the basis of a multi-domain structure, the multi-domain display further enables the branch electrodes (16) of the sub-pixels (10) corresponding to different colors and transmission axes of the polarizers (2) and (3) to have different included angles (θ), so that the degree difference of the voltage transmission rate curve deviation of red, green and blue sub-pixels (10) under squinting and emmetropia is reduced, the visual angle color shift problem of the liquid crystal display panel (1) can be effectively improved, and the structure and a manufacturing method are simple and do not result in other additional manufacturing process and a cost impact.

Description

Multi-domain LCD

Technical field

The invention relates to the field of display technology, in particular to a multi-domain liquid crystal display.

Background technique

Liquid crystal display (LCD) has many advantages such as thin body, power saving, no radiation, etc. It has been widely used, such as LCD TV, mobile phone, personal digital assistant (PDA), digital camera, computer screen or Laptop screens, etc., dominate the field of flat panel displays.

Active Thin Film Transistor Liquid Crystal Display (Thin Film Transistor-LCD, TFT-LCD) is currently the most common liquid crystal display in the mainstream market, which can be roughly divided into: Twisted Nematic (TN) or Super Twisted Nematic (STN) type, In-Plane Switching (IPS) type, and Vertical Alignment (VA) type. Among them, VA type liquid crystal display has extremely high contrast with other types of liquid crystal displays, and has a very wide range of applications in large-size display, such as TV.

Although TFT-LCD has many advantages, there are also many areas that need to be improved. For example, too small viewing angle is one of the important issues that affect the display quality of TFT-LCD. The phenomenon that the display panel has a color shift as the viewing angle becomes larger is also referred to as a large-vision role shift. The big-vision role bias specifically refers to the phenomenon that the color of a liquid crystal display panel (especially a VA-type liquid crystal display panel) is relatively deviated from the front view when viewed at a large angle, for example, in the case of front view The color performance of the LCD panel is normal, but when viewed from a large viewing angle (60 °), the color of the LCD panel is abnormal, as if it was washed with water.

At present, in order to solve the problem of large-vision role deviation of liquid crystal display panels, people have proposed various designs to achieve low color shift of the liquid crystal display panel, such as 2D1G technology, 3T technology and charge sharing technology. The current common technology to solve the color shift problem of VA type liquid crystal display panel. The main common point of these designs is that each sub-pixel of the LCD panel is divided into a main (sub) pixel area and a sub (sub) pixel area, and then the liquid crystal molecules of the main pixel area and the sub pixel area are deflected by various methods There are differences in angles to improve the prevalence of big vision roles. Among them, 2D1G technology is to provide signals to the Main pixel area and Sub pixel area, which brings the possibility of improving the display effect of large viewing angles by using unused gamma curves. 3T and Charge sharing technologies essentially divide a sub-pixel display area into two parts with different brightness. When using different frontal brightness, the difference in strabismus brightness can adjust the gamma curve of strabismus.

The technology based on the above principles is often achieved by capacitive coupling or multi-TFT control. The method based on capacitive coupling has been widely used, but it also has some problems, such as: 1. The degree of capacitive coupling is in different manufacturing processes There are differences, and it is difficult to adjust due to the difficulty of adjusting the thickness and dimensional accuracy of the conductive layer in the manufacturing process; 2. At different voltages, the voltage of the sub pixel area (Vsub) generated by the coupling is not necessarily linear, and at the same time is different Under the gray scale, Vsub is affected by the characteristics of the semiconductor and its process. Even if the same design is used, the improvement effect is different under different equipment and processes; 3. The method of dividing the pixel into different areas and using different voltage driving will reduce LCD aperture ratio, thereby reducing the transmittance of the display.

1 is a normalized voltage transmittance (VT) curve diagram of a red, green, and blue (R / G / B) sub-pixel of an existing liquid crystal display at an oblique view of 0 ° and an oblique view of 30 °, as can be seen from FIG. 1 It is shown that the front VT curve and the strabismus VT curve of the red, green and blue sub-pixels do not overlap, and the dispersion degree of the blue sub-pixel is higher. In principle, the difference between the side view and the front view of the same picture, except for the brightness, is more from the separation of the red, green and blue sub-pixels' VT curve under front and strabismus, especially when strabismus, red and green The degree of deviation of the blue sub-pixels is different.

Summary of the invention

An object of the present invention is to provide a multi-domain liquid crystal display, which can improve the problem of the parallax of the liquid crystal display panel.

To achieve the above object, the present invention provides a multi-domain liquid crystal display, including an LCD panel, an incident-side polarizer provided on the light-incident side of the LCD panel, and an exit-side polarizer provided on the light-exit side of the LCD panel;

The LCD panel includes a plurality of pixel structures arranged in an array, each of the pixel structures includes at least two types of sub-pixels respectively corresponding to different colors, each of the sub-pixels is divided into at least four domain regions, and each domain region Including multiple branch electrodes parallel to each other and distributed at intervals;

The transmission axis of the incident side polarizer is a first direction, and the transmission axis of the output side polarizer is a second direction perpendicular to the first direction;

There are at least two different angles between the branch electrodes corresponding to the sub-pixels of different colors and the first direction.

Each pixel structure includes three types of sub-pixels corresponding to red, green, and blue, namely red, green, and blue sub-pixels;

The branch electrode in the red sub-pixel is the first branch electrode;

The branch electrode in the green sub-pixel is a second branch electrode;

The branch electrode in the blue sub-pixel is a third branch electrode.

The angle between the third branch electrode and the first direction is smaller than the angle between the first branch electrode and the first direction and the angle between the second branch electrode and the first direction.

The angle between the first branch electrode and the first direction is 45 °, the angle between the second branch electrode and the first direction is 45 °, and the third branch electrode and the first direction The included angle is 35 °.

The angle between the first branch electrode and the first direction is 40 °, the angle between the second branch electrode and the first direction is 40 °, and the third branch electrode and the first direction The included angle is 30 °.

The angle between the third branch electrode and the first direction is greater than the angle between the first branch electrode and the first direction and the angle between the second branch electrode and the first direction.

The multi-domain liquid crystal display further includes a backlight module disposed on the side of the incident side polarizer away from the LCD panel.

Each of the sub-pixels includes a first stem electrode parallel to the first direction and a second stem electrode parallel to the second direction, the first stem electrode and the second stem electrode divide the sub-pixel into four domains region.

The multi-domain liquid crystal display is a vertical alignment type liquid crystal display.

Beneficial effect of the present invention: The present invention provides a multi-domain liquid crystal display including an LCD panel, an incident side polarizer and an exit side polarizer. The LCD panel includes a plurality of pixel structures arranged in an array, each of the pixels The structure includes at least two kinds of sub-pixels corresponding to different colors respectively, and each of the sub-pixels is divided into at least four domain regions, and each domain region includes a plurality of branch electrodes that are parallel and spaced apart from each other, and at least two types respectively correspond to different The angle between the branch electrode of the color sub-pixel and the transmission axis of the incident side polarizer is different. Compared with the prior art, the present invention further makes the corresponding sub-pixels of different colors based on the multi-domain structure The branch electrode and the transmission axis of the polarizer have different included angles, so that the voltage transmittance curve of the sub-pixels corresponding to different colors in the pixel structure is more concentrated, and the voltage transmission of the red, green, and blue sub-pixels under oblique and front views is reduced. The difference in the degree of deviation of the over-rate curve can effectively improve the deviation of the visual role of the liquid crystal display panel, and the structure and manufacturing method are simple, and will not bring other additional measures. And cost implications.

BRIEF DESCRIPTION

In order to further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, the drawings are provided for reference and explanation only, and are not intended to limit the present invention.

In the drawings,

1 is a normalized voltage transmittance curve diagram of red, green and blue sub-pixels of an existing liquid crystal display in front view and oblique view;

2 is a schematic structural diagram of a multi-domain liquid crystal display of the present invention;

3 is a schematic structural view of a sub-pixel in the multi-domain liquid crystal display of the present invention;

4 is a schematic diagram of a pixel structure in a multi-domain liquid crystal display of the present invention.

detailed description

In order to further elaborate on the technical means adopted by the present invention and its effects, the following will be described in detail with reference to the preferred embodiments of the present invention and the accompanying drawings.

Referring to FIG. 2, the present invention provides a multi-domain liquid crystal display, including an LCD panel 1, an incident-side polarizer 2 provided on the light-incident side of the LCD panel 1, and an exit-side polarized light provided on the light-emitting side of the LCD panel 1 The sheet 3 and the backlight module 4 provided on the side of the incident side polarizer 2 away from the LCD panel 1.

As shown in FIGS. 3-4, the LCD panel 1 includes a plurality of pixel structures 5 arranged in an array, each of the pixel structures 5 includes at least two types of sub-pixels 10 corresponding to different colors, and each of the sub-pixels 10 is divided into at least four domain regions 15, and each domain region 15 includes a plurality of branch electrodes 16 that are parallel to each other and spaced apart.

The transmission axis of the incident side polarizer 2 is the first direction X, and the transmission axis of the output side polarizer 3 is the second direction Y perpendicular to the first direction X.

In the multi-domain liquid crystal display of the present invention, each sub-pixel 10 is divided into at least four domain regions, which can compensate the color shift of the horizontal viewing angle of the liquid crystal display to a certain degree. Compared with the pixel structure of one domain and two domains, the display quality of the display is more high. But this kind of multi-domain structure cannot fully make the deviation of the big-sighted character return to an acceptable level.

It should be noted that in the liquid crystal transmittance formula of a vertical alignment (VA) liquid crystal display, there is a sin2ψ term, and ψ is the angle between the optical axis of the liquid crystal and the transmission axis of the polarizer. Therefore, in a general VA liquid crystal display, The branch electrode 16 is always at an angle of 45 ° to the transmission axis of the polarizer, that is, at an angle of 45 ° between the first direction X and the second direction Y, so that under a white screen, the electric field direction of the liquid crystal molecules is The vertical branch electrode 16 also forms an angle of 45 degrees with the transmission axis of the polarizer, so as to achieve the purpose of maximum transmittance. The inventor of the present invention found in a simulation test that when the angle between the branch electrode 16 and the first direction X becomes lower and lower, the light intensity emitted by the corresponding sub-pixel 10 in the first direction X viewing angle also increases Lower. When the angle between the branch electrode 16 and the first direction X deviates from 45 degrees, it will cause the transmittance of the LCD to decrease, and will cause the pixels to emit out of balance in the upper, lower, left, and right directions, that is, when the angle of 45 degrees cannot be reached. The viewing angle compensation effect of the direction X and the second direction Y is symmetrical. However, assuming that what we need to improve is the color shift problem in the first direction X, it can be achieved by modifying the angle between the branch electrode 16 of a specific sub-pixel and the first direction X.

Therefore, based on the above principle, on the premise of adopting the multi-domain structure, the present invention further makes the angle between the branch electrodes 16 of at least two sub-pixels 10 corresponding to different colors and the first direction X different to match The VT curve of the sub-pixel 10 is adjusted to further improve the deviation of the visual role caused by the deviation of the VT curve shown in FIG. 1.

Specifically, the multi-domain liquid crystal display of the present invention includes three sub-pixels 10 corresponding to red, green, and blue, respectively, a red sub-pixel 11, a green sub-pixel 12, and a blue sub-pixel 13, respectively.

Specifically, the branch electrode 16 in the red sub-pixel 11 is the first branch electrode 161; the branch electrode 16 in the green sub-pixel 12 is the second branch electrode 162; the blue sub-pixel 13 The branch electrode 16 in is a third branch electrode 163.

Specifically, each sub-pixel 10 is divided into four domain regions 15 in two rows and two columns.

Specifically, each of the sub-pixels 10 includes a first main electrode 17 parallel to the first direction X and a second main electrode 18 parallel to the second direction Y, the first main electrode 17 and the second main electrode 18 The sub-pixel 10 is divided into four domain regions 15.

Specifically, the voltage transmissivity curves of the red, green, and blue sub-pixels 11/12/13 in the prior art under front view and strabismus are shown in FIG. 1, as can be seen from FIG. 1 Next, the VT curve of the oblique view of the blue sub-pixel 13 deviates the most from the VT curve of the front view. Therefore, the absolute value of the difference between the angle between the branch electrode 16 and the first direction X and 45 ° is the branch For the adjustment angle of the electrode 16, in the embodiment of the present invention, the adjustment angle of the third branch electrode 163 of the blue sub-pixel 13 is preferably greater than the adjustment angle of the first branch electrode 161 of the red sub-pixel 11 and the green sub-pixel The angle of the second branch electrode 162 of 12 is adjusted to reduce the deviation of the VT curve of the red, green, and blue sub-pixels 11/12/13 in squint and front views, thereby improving the deviation of the visual role of the LCD panel.

Specifically, for example, for the existing liquid crystal display panel, there is usually a problem of the deviation of the color of the skin color. The main reason is that the brightness of the blue sub-pixel 13 when it is squinted is too large relative to the brightness of the red sub-pixel 11 and the green sub-pixel 12, At this time, assuming that what we need to improve is the color shift problem in the first direction X, then we can separately adjust the blue sub-pixel 13 by combining the third branch electrode 163 of the blue sub-pixel 13 with the first The angle θ3 between one direction X is set to <45 °, and the angle θ1 between the first branch electrode 161 of the red sub-pixel 11 and the first direction X and the second branch electrode of the green sub-pixel 12 The angle θ2 between 162 and the first direction X is maintained at 45 °, which can achieve the purpose of improving the deviation of the visual role in the first direction X; or, adjust the red sub-pixel 11 and the green sub-pixel 12 to change the The angle θ1 between the first branch electrode 161 of the red sub-pixel 11 and the first direction X and the angle θ2 between the second branch electrode 162 of the green sub-pixel 12 and the first direction X are set to> 45 °, and the third branch electrode 163 of the blue sub-pixel 13 The angle θ3 between one direction X and 45 degrees is maintained to achieve the purpose of improving the deviation of the visual role in the first direction X; The setting smaller than the included angle θ1 between the first branch electrode 161 and the first direction X and the included angle θ2 between the second branch electrode 162 and the first direction X can improve the upward viewing role in the first direction X Partial purpose.

Exemplarily, the included angle θ1 between the first branch electrode 161 and the first direction X is 45 °, and the included angle θ2 between the second branch electrode 162 and the first direction X is 45 °, The angle θ3 between the third branch electrode 163 and the first direction X is 35 °.

Exemplarily again, the angle θ1 between the first branch electrode 161 and the first direction X is 40 °, and the angle θ2 between the second branch electrode 162 and the first direction X is 40 °, so The angle θ3 between the third branch electrode 163 and the first direction X is 30 °.

It should be noted that in the embodiment of the present invention, the included angle θ1 between the first branch electrode 161 and the first direction X1, the included angle θ2 between the second branch electrode 162 and the first direction X, and all The angle θ3 between the third branch electrode 163 and the first direction X is not limited to the specific dimensions described above.

Similarly, assuming that we need to improve the color shift problem in the second direction Y, then we can make the angle θ3 between the third branch electrode 163 and the first direction X greater than the first branch electrode 161 The angle θ1 between the first direction X and the angle θ2 between the second branch electrode 162 and the first direction X can achieve the purpose of improving the deviation of the visual role in the second direction Y.

In the multi-domain liquid crystal display of the present invention, each of the sub-pixels 10 is divided into at least four domain regions 15. This multi-domain structure can compensate the color shift of the horizontal viewing angle of the liquid crystal display to a certain degree, and further enable at least two The angle between the branch electrode 16 corresponding to the sub-pixel 10 of different colors and the transmission axis of the incident-side polarizer 2 is different to adjust the VT curve of the corresponding sub-pixel 10 so that the pixel structure 5 corresponds to different colors The VT curve of the sub-pixel 10 is more concentrated, reducing the deviation of the VT curve of the red, green and blue sub-pixels 11/12/13 under strabismus and front view, thereby further improving the visual role deviation of the LCD panel, especially for The problem of the deviation of the visual alignment of the vertical alignment type liquid crystal display, and the structure and manufacturing method are simple, and will not bring other additional processes and cost effects.

In summary, the present invention provides a multi-domain liquid crystal display including an LCD panel, an incident side polarizer and an exit side polarizer. The LCD panel includes a plurality of pixel structures arranged in an array, each of the pixel structures At least two sub-pixels corresponding to different colors are respectively included, and each of the sub-pixels is divided into at least four domain regions, and each domain region includes a plurality of branch electrodes parallel and spaced apart from each other, and at least two sub-pixels corresponding to different colors, respectively The angle between the branch electrode of the sub-pixel and the transmission axis of the incident side polarizer is different. Compared with the prior art, the present invention further branches the sub-pixels corresponding to different colors on the basis of the multi-domain structure The angle between the electrode and the transmission axis of the polarizer has different angles, so that the voltage transmission curve of the sub-pixels corresponding to different colors in the pixel structure is more concentrated, and the voltage transmission of the red, green, and blue sub-pixels in oblique and front views is reduced The difference in the degree of deviation of the rate curve can effectively improve the deviation of the visual role of the LCD panel, and the structure and manufacturing method are simple, which will not bring other additional processes and costs influences.

As mentioned above, those of ordinary skill in the art can make various other corresponding changes and modifications according to the technical solutions and technical concepts of the present invention, and all such changes and modifications should fall within the protection scope of the claims of the present invention. .

Claims

A multi-domain liquid crystal display, comprising an LCD panel, an incident side polarizer provided on the light incident side of the LCD panel, and an exit side polarizer provided on the light exit side of the LCD panel;

The LCD panel includes a plurality of pixel structures arranged in an array, each of the pixel structures includes at least two types of sub-pixels respectively corresponding to different colors, each of the sub-pixels is divided into at least four domain regions, and each domain region Including multiple branch electrodes parallel to each other and distributed at intervals;

The transmission axis of the incident side polarizer is a first direction, and the transmission axis of the output side polarizer is a second direction perpendicular to the first direction;

There are at least two different angles between the branch electrodes corresponding to the sub-pixels of different colors and the first direction.
The multi-domain liquid crystal display of claim 1, wherein each of the pixel structures includes three sub-pixels corresponding to red, green, and blue, namely a red sub-pixel, a green sub-pixel, and a blue sub-pixel;

The branch electrode in the red sub-pixel is the first branch electrode;

The branch electrode in the green sub-pixel is a second branch electrode;

The branch electrode in the blue sub-pixel is a third branch electrode.
The multi-domain liquid crystal display of claim 2, wherein the angle between the third branch electrode and the first direction is smaller than the angle between the first branch electrode and the first direction and the second branch electrode Angle to the first direction.
The multi-domain liquid crystal display of claim 3, wherein the angle between the first branch electrode and the first direction is 45 °, and the angle between the second branch electrode and the first direction is 45 °, the angle between the third branch electrode and the first direction is 35 °.
The multi-domain liquid crystal display of claim 3, wherein the angle between the first branch electrode and the first direction is 40 °, and the angle between the second branch electrode and the first direction is 40 °, the angle between the third branch electrode and the first direction is 30 °.
The multi-domain liquid crystal display of claim 2, wherein the angle between the third branch electrode and the first direction is greater than the angle between the first branch electrode and the first direction and the second branch electrode Angle to the first direction.
The multi-domain liquid crystal display of claim 1, further comprising a backlight module disposed on the side of the incident side polarizer away from the LCD panel.
The multi-domain liquid crystal display of claim 1, wherein each of the sub-pixels is divided into four domain regions in two rows and two columns.
The multi-domain liquid crystal display of claim 8, wherein each of the sub-pixels includes a first stem electrode parallel to the first direction and a second stem electrode parallel to the second direction, the first stem electrode and The second main electrode divides the sub-pixel into four domain regions.
The multi-domain liquid crystal display according to claim 1, which is a vertical alignment type liquid crystal display.