WO2019029086A1

WO2019029086A1 - Liquid crystal display device

Info

Publication number: WO2019029086A1
Application number: PCT/CN2017/116670
Authority: WO
Inventors: 李富琳; 宋志成; 刘卫东
Original assignee: 青岛海信电器股份有限公司
Priority date: 2017-08-09
Filing date: 2017-12-15
Publication date: 2019-02-14

Abstract

A liquid crystal display device, comprising a liquid crystal panel (500). The liquid crystal panel (500) includes: stacked in sequence, quantum dot color pixel layers (521, 522, 523), an upper polarizer (512), a liquid crystal switch unit (511) and a lower polarizer (510); and a backlight module (400). A light emitting device (410) of the backlight module (400) includes a light emitting source (200) and an optical collimating device (300). According to the lagrange invariant, the optical collimating device (300) is disposed above the light emitting source (200), thus increasing light exit aperture, decreasing backlight outgoing angle and improving the problem of pixel-to-pixel color crosstalk.

Description

Liquid crystal display device

This application is required to be submitted to the China Patent Office on August 9, 2017. The application number is 201710675141.7, the application name is “a liquid crystal display device”, the application number is 201710675428.X, and the application name is “a liquid crystal display device”. No. 201710675426.0, the application name is "a liquid crystal display device", the application number is 201710675427.5, the application name is "a liquid crystal display device", the application number is 201710675409.7, and the application name is "a liquid crystal display device", the application number is The application is entitled "A Liquid Crystal Display Device" and the priority of the Chinese Patent Application No. Hei. No. Hei. No. Hei.

Technical field

The present application relates to the field of display technologies, and in particular, to a liquid crystal display device.

Background technique

In a novel display mode of a liquid crystal television, a quantum dot color pixel layer directly replaces a color filter in a conventional liquid crystal panel, and mainly includes a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit, wherein The red sub-pixel unit is provided with a red quantum dot material; the green sub-pixel unit is provided with a green quantum dot material; the blue sub-pixel unit is not provided with a quantum dot material or a blue quantum dot material. When the blue backlight is illuminated on the three pixel units of red, green and blue, the blue backlight in the blue sub-pixel unit directly transmits or interacts with the blue quantum dots to emit blue light; the quantum dot material in the green sub-pixel unit The absorption of blue light is converted into green light, and the quantum dot material in the red sub-pixel unit absorbs blue light and is converted into red light.

Since the quantum dot material is excited to emit fluorescence, it changes the physical conduction property and polarization direction of the light, especially when excited by polarized blue light, the fluorescence emitted by the quantum dot material is unpolarized, thereby making the quantum dot material preparation. The liquid crystal panel is different from the liquid crystal panel structure prepared by the conventional color filter, and the position of the polarizing plate needs to be adjusted, so that the liquid crystal panel is sequentially stacked and arranged as a quantum dot color pixel layer, an upper polarizing plate, a liquid crystal layer and a lower polarizing plate. The three layers of the upper polarizing plate, the liquid crystal layer and the lower polarizing plate are mainly used for controlling the light intensity of the transmitted light, and the quantum dot color pixel layer receives the excitation of different intensity lights to generate a color display with different brightness.

Summary of the invention

The present application provides a liquid crystal display device including a liquid crystal panel and a backlight module, wherein the liquid crystal panel includes: a liquid crystal layer, and an upper polarizing plate and a lower polarizing plate are disposed on the upper side and the lower side of the liquid crystal layer, and a quantum Pointing a color pixel layer, the quantum dot color pixel layer being disposed above the upper polarizing plate;

The backlight module includes a back plate and a light emitting device, and the light emitting device includes an illuminating light source and an optical collimating device; The optical collimating device is disposed above the illuminating light source.

DRAWINGS

The drawings herein are incorporated in and constitute a part of the specification,

In order to more clearly illustrate the technical solutions in the embodiments of the present application or the related art, the following description of the embodiments or related art, the drawings used in the description will be briefly introduced. Obviously, the drawings in the following description are merely Some embodiments of the present application can also obtain other drawings based on these drawings without departing from the prior art by those skilled in the art.

1 is a schematic diagram of color crosstalk between pixels in the related art;

2 is a schematic structural diagram of a liquid crystal display device according to some embodiments of the present application;

3 is a schematic diagram showing an optical display principle of a liquid crystal display device according to some embodiments of the present application;

4 is a schematic diagram of the optical principle of uniformity in some embodiments of the present application;

Figure 5 is a liquid crystal display device according to another embodiment of the present application;

FIG. 6 is a schematic structural diagram of a light emitting device according to another embodiment of the present application; FIG.

7 is a schematic diagram of optical path distribution of a light emitting device in other embodiments of the present application;

FIG. 8 is a schematic diagram showing optical improvement effects of a liquid crystal display device according to other embodiments of the present application; FIG.

FIG. 9 is a schematic structural view showing a modification of a light emitting device according to another embodiment of the present application; FIG.

FIG. 10 is a schematic diagram of optical path distribution of a modification of a light emitting device according to another embodiment of the present application; FIG.

11 is a schematic structural diagram of a backlight module of a liquid crystal display device provided in still another embodiment of the application;

12 is a schematic structural diagram of an embodiment of a beam expander according to still another embodiment of the present application;

FIG. 13 is a schematic structural diagram of an embodiment of a collimating plate according to still another embodiment of the present application;

FIG. 14 is a schematic structural diagram of a backlight module of a liquid crystal display device according to still another embodiment of the application.

Reference mark:

100-backlight source 110-lower polarizer 111-liquid crystal cell

112-upper polarizing plate 121-red pixel unit 122-green pixel unit

123-blue pixel unit 200-LED light source 210-liquid crystal layer

211-upper polarizer 212-lower polarizer 212 220-quantum dot color pixel layer

221-red sub-pixel unit 222-green sub-pixel unit 223-blue sub-pixel unit

224-black matrix 230-lighting device 300-optical collimating device

310-support frame 320-collimator 321-lighting surface

321a-first light entrance surface 321b-second light entrance surface 321c-third light entrance surface

322-light-emitting surface 322a-first positive slope light-emitting surface 322b-first negative-slope light-emitting surface

322c-plane 322d-second positive slope light exit surface 322e-second negative slope light exit surface

400-backlight module 410-lighting device 420-backplane

500-LCD panel 510-lower polarizer 511-liquid crystal cell

512-upper polarizer 521-red pixel unit 522-green pixel unit

523-blue pixel unit 21-lighting device 22-beam expander

23-collimation plate 225-input negative lens 231-output positive lens

31-Light-emitting device 32-beam expander 33-collimation plate

34-collimating lens

Detailed ways

The technical solutions in the embodiments of the present application are clearly and completely described in the following with reference to the drawings in the embodiments of the present application. It is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without departing from the inventive scope are the scope of the present application.

In the description of the present application, it is to be understood that the terms "upper", "lower", "horizontal", "vertical", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the drawings, only for the purpose of The present application and the simplifications of the present invention are not to be construed as limiting the scope of the application. The terms "first", "second", and "third" are used for descriptive purposes only, and are not to be construed as indicating or implying a relative importance or implicitly indicating or implied, including one or more of the technical features.

In the process of realizing the liquid crystal panel in the related art, it is found that a new quantum dot panel structure is disposed between the quantum dot color pixel layer and the liquid crystal layer due to a certain divergence angle of the backlight, and the structure changes due to the structure. It will bring serious crosstalk problems between different pixels in the quantum dot liquid crystal panel.

For example, as shown in FIG. 1 , the green sub-pixel unit 122 is in an open state, the red sub-pixel unit 121 and the blue sub-pixel unit are in a state in which the liquid crystal switching unit of the liquid crystal layer 111 is in an open state. The liquid crystal switch unit corresponding to 123 is in a closed state. However, the backlight light-emitting device 100 provides a large backlight exit angle. After the blue backlight is processed by the lower polarizer 110, the liquid crystal layer 111 and the upper polarizer 112, the divergence angle is still large. Irradiation to adjacent red sub-pixel unit 121 and blue sub-pixel unit 123 to cause red sub-pixel unit 121 is also excited by the blue backlight to generate red light, and the light passing through the blue sub-pixel unit 123 is directly transmitted, so that the excitation light used to display the green pixel enters the adjacent other color sub-pixel unit, and when the green color is displayed Doped with red and blue, which reduces color purity. Similarly, red sub-pixels and sub-blue pixels also have color crosstalk problems.

For the above-mentioned inter-pixel color crosstalk problem, a black matrix (ie, a BM region) between each sub-pixel is mainly used to prevent ray crosstalk between adjacent sub-pixels. In order to improve the blocking efficiency of the black matrix, two methods can be generally selected to solve the problem: 1. directly increase the width of the black matrix between the sub-pixels, and expand the black matrix to the diverging ray blocking range; 2. reduce the quantum dot color pixel layer and the liquid crystal layer. The thickness of the upper polarizing plate and other substrate layers are reduced to reduce the distance of the divergent rays in the horizontal direction so that the offset distance is within the black matrix blocking range, thus facilitating the black matrix to block between adjacent sub-pixels Light crosstalk.

However, on the one hand, actually increasing the display brightness is a common requirement of display technology. When the resolution is continuously increased, a black matrix needs to be set around each pixel, and the ratio of the display pixel area to the visible area is continuously lowered, resulting in further display brightness. Therefore, in order to improve the display brightness, it is necessary to increase the effective display area ratio of the liquid crystal panel, and accordingly, it is required to minimize the proportion of the black matrix between the pixels. Therefore, it is common practice in the industry to improve the technology to reduce the size of the black matrix. Display brightness; on the other hand, the polarizer is usually a composite film structure, the thickness of which is generally greater than 100 micrometers, and the thickness thereof is generally further reduced by improving the preparation process and materials, but the improvement is extremely difficult. Generally, the width of the conventional conventional BM region can reach 20 micrometers or less. Compared with the polarizing plate of known thickness in the existing liquid crystal display device, the BM region of the existing width isolates the adjacent pixel light. The effect is limited. Even if the structural form or preparation process of the polarizing plate is broken to reduce the thickness thereof, it is difficult to effectively solve the influence of the color crosstalk problem caused by the thickness of the polarizing plate.

As shown in FIG. 2, the liquid crystal display device includes a liquid crystal panel and a backlight module.

The liquid crystal panel includes a liquid crystal layer 210, and an upper polarizing plate 211 and a lower polarizing plate 212, and a quantum dot color pixel layer 220 are disposed on the upper side and the lower side of the liquid crystal layer 210.

The liquid crystal layer 210 controls the twist direction of the liquid crystal molecules in the liquid crystal switch unit corresponding to each pixel through the TFT driving circuit, and the upper polarizing plate 211 and the lower polarizing plate 212 are matched to control the amount of light transmitted through each pixel.

And a quantum dot color pixel layer 220 is disposed on the upper surface of the upper polarizing plate 211. The quantum dot color pixel layer 220 includes a plurality of color sub-pixel units arranged in phase and a black matrix 224 between each sub-pixel unit, wherein the black matrix 224 is for absorbing light to prevent ray crosstalk between adjacent sub-pixel units, and each sub-pixel unit can be excited by the transmitted excitation light to generate fluorescence or direct transmission to generate light of a desired corresponding color.

The multi-color sub-pixel unit includes a red sub-pixel unit 221, a green sub-pixel unit 222, and a blue sub-pixel unit Yuan 223. Of course, in order to improve the display effect, other color sub-pixel units, such as white sub-pixel units (not shown in FIG. 2), may also be provided.

In some embodiments, when the blue light emitting device is used, according to the quantum dot excitation light emitting principle, the green sub-pixel unit 222 is encapsulated with a green quantum dot material, and the red sub-pixel unit 221 is encapsulated with a red quantum dot material, the blue sub- The pixel unit 223 can directly transmit the blue excitation light, and can also encapsulate other blue quantum dot materials as needed. Of course, other excitation light having a shorter wavelength and more energy can be used as the light-emitting device, such as ultraviolet light.

The backlight module includes a light emitting device 230 and other backlight assemblies, wherein the light emitting device is used to provide light required for the liquid crystal panel to display an image. In the embodiment of the present application, only the structural components related to the present application are shown to explain the specific implementation process of the present application. Those skilled in the art can set other backlight components such as optical components, such as optical substrates and other optical films, as needed. And optical alignment devices, or diffusion members, etc., which are specifically provided in other embodiments of the present application.

In order to ensure that color crosstalk does not occur between sub-pixel units of each color, it is necessary to avoid transmitting light of the liquid crystal switch unit corresponding to each sub-pixel unit into its adjacent sub-pixel unit, thereby preventing light between the sub-pixels. Crosstalk. As shown in FIG. 3, in order to prevent the red sub-pixel unit 221 from entering the blue sub-pixel unit 223 or the green sub-pixel unit 222 corresponding to the light controlled by the liquid crystal switch unit, the red sub-pixel unit 221 corresponds to the liquid crystal switch unit. The angle exiting light must not enter the adjacent green sub-pixel 222.

Therefore, in order to reduce the possibility of crosstalk between the sub-pixels, the divergence angle of the light emitted from the liquid crystal layer must be reduced, and it can be realized by providing an optical collimating device for collimating the light emitted from the light-emitting device over the light-emitting device. The optical collimating member may be such that the divergence angle of the light emitted by the illuminating light source becomes relatively convergent.

As shown in FIG. 5 , the display device includes a liquid crystal panel 500 and a backlight module 400 for providing a backlight. The liquid crystal panel 500 is opposite to the backlight module 400 , and the liquid crystal panel 500 is disposed above the backlight module 400 .

The liquid crystal panel 500 includes a quantum dot color pixel layer 520, an upper polarizing plate 512, a liquid crystal cell 511, and a lower polarizing plate 510 which are sequentially stacked, and the quantum dot color pixel layer 520 includes a plurality of red pixel units 521 and a plurality of green pixel units 522 and A plurality of blue pixel 523 units, wherein the red pixel unit 521 is provided with a red quantum dot material, the green pixel unit 522 is provided with a green quantum dot material, and the blue pixel unit 523 is not provided with a quantum dot material. The blue backlight is processed by the lower polarizer 510, passes through the liquid crystal cell 511, and then transmitted through the upper polarizing plate 512 to the three pixel units of red, green and blue. The red quantum dot material in the red pixel unit 521 absorbs blue light and can be converted into In the red light, the green quantum dot material in the green pixel unit 522 absorbs blue light and can be converted into green light, and the blue backlight in the blue pixel unit 523 can directly transmit blue light. The three layers of the upper polarizing plate, the liquid crystal cell and the lower polarizing plate are mainly used for controlling the light intensity of the transmitted light, and the quantum dot color pixel layer receives the excitation of different intensity lights, and the color display of different brightness is generated.

The backlight module 400 includes a back plate 420 and a plurality of light emitting devices 410 disposed above the back plate, in some embodiments The specific structure of the light emitting device 410 can be referred to FIG. 6. The light emitting device 410 includes an illuminating light source 200 and an optical collimating device 300 disposed above the illuminating light source 200.

The optical collimating device is an optical device for turning divergent rays into near parallel rays.

In some embodiments, the illuminating light source is an LED light source.

The optical collimating device 300 in this embodiment includes a support frame 310 and a collimator 320 located between the support frames. The collimator 320 includes a light incident surface 321 and a light exit surface 322. In some embodiments, the light incident surface 321 and the light exit surface 322 are respectively circumferentially symmetric.

In some embodiments, the slope of the light incident surface 321 of the collimator 320 is different and is convex.

In some embodiments, the light incident surface 321 is designed in three stages, and the sequence includes a first sub-light incident surface 321a having a negative slope, a second sub-light incident surface 321b having a zero slope, and a third sub-input light having a positive slope. The surface 321c, the light-emitting surface 322 is set to be a flat surface.

As shown in FIG. 7, the angle between the first sub-light incident surface 321a and the inner surface of the support frame 310 is ∠0, and the third sub-light incident surface 321c and the first sub-light incident surface 321a are symmetrical with each other.

In some embodiments, the angle between the light having the largest incident angle and the light having the smallest incident angle is ∠A through the first sub-light incident surface 321a; and the incident light of the two ends of the second sub-light incident surface 321b The angle is ∠B; through the third sub-lighting surface 321c, the angle between the light having the largest incident angle and the light having the smallest incident angle is ∠C.

In some embodiments, a certain incident light is incident through the first sub-light incident surface 321a, the angle between the incident light and the vertical direction is ∠1, and the angle between the incident angle of the first sub-light incident surface 321a is ∠2; after refraction, the angle between the refracted ray and the normal of the first sub-lighting surface 321a is ∠3, and the angle between the normal line of the illuminating surface 322 is ∠4; after exiting through the illuminating surface, the exit The angle between the light and the normal of the exit surface is the exit angle ∠5.

In Fig. 7, ∠6 is an exit angle formed by the incident light passing through the first sub-light incident surface 321a and then exiting through the light exit surface 322, and the outgoing light and the normal of the light exiting surface.

In some embodiments, the refractive index n and ∠1 are known, assuming ∠0 is known, then:

∠2=∠1+90°-∠0

According to the law of refraction: sin∠2=n*sin∠3

∠3=arcsin(sin∠2/n)=arcsin[sin(∠1+90°-∠0)/n]

∠4=∠3-(90°-∠0)=arcsin[sin(∠1+90°-∠0)/n]-90°+∠0

According to the law of refraction: sin∠5=n*sin∠4

∠5=arcsin(n*sin∠4)=arcsin{n*sin{arcsin[sin(∠1+90°-∠0)/n]-90°+∠0}}

In some embodiments, for another incident ray, ∠1 changes, and similarly, the relationship between ∠6 and ∠0 can be derived:

∠6=arcsin{n*sin{arcsin[sin(∠1+90°-∠0)/n]-90°+∠0}}

In some embodiments, ∠1 is a given value in the above formula, and when ∠1=(∠A+∠B+∠C)/2, the incident angle of the ray is the largest, and the incident light at the angle passes through the embodiment. After the collimated structure emerges, the exit angle ∠5 is the maximum angle in the negative slope direction; when ∠1=∠B/2, the ray incident angle is the smallest, and the incident light at the angle passes through the collimating structure in this embodiment. After exiting, the exit angle ∠6 is the maximum angle in the positive slope direction.

In some embodiments, the optical collimating device in this embodiment gives an angle ∠B formed by incident light rays at both ends of the second sub-into-light surface, the first sub-into-light surface of the collimator and the inner surface of the support frame. The angle ∠0 between the two is satisfied: the above-mentioned incident light passing through the first sub-input plane is emitted through the light-emitting surface, and the maximum exit angle ∠5 in the negative slope direction is equal to the maximum exit angle ∠6 in the positive slope direction. Both are equal to half of ∠B.

Other components of the liquid crystal panel and the backlight module of the present invention are well known to those skilled in the art, and can be referred to the related art in the related art, and will not be described in detail herein.

In the liquid crystal display device provided by the embodiment, an optical alignment device is disposed above the illuminating light source of the illuminating device, and the light-emitting surface of the collimator of the collimating structure is a plane, and the light-incident surface is sequentially set with a negative slope into the light surface, the plane, and the positive The slope enters the three sections of the light surface, thereby increasing the exit aperture of the light. According to the Lach invariant in the optical, the exit aperture is increased, and the light exit angle is inevitably reduced, so that the light achieves a certain degree of collimation and exit. Further, the problem of color crosstalk between different pixel units caused by the backlight light exit angle when the liquid crystal panel is displayed on the screen is improved, and a schematic diagram of improving the color crosstalk problem is shown in FIG. 8.

In some embodiments, referring to FIG. 9, the optical collimating device 300 includes a support frame 310 and a collimator 320 disposed between the support frames. The collimator 320 includes a light incident surface 321 and a light exit surface 322, and enters the light. The surface 321 and the light-emitting surface 322 are respectively circumferentially symmetric. In addition, the structure of the light-incident surface 321 of the light-emitting device and the angle between the first sub-light incident surface 321a and the inner surface of the support frame 310 are satisfied. It is described in detail in the above embodiments, and details are not described herein again.

In some embodiments, the illuminating surface is convex or planar.

In some embodiments, the light exit surface 322 sequentially includes a first positive slope light exit surface 322a, a first negative slope light exit surface 322b, a plane 322c, a second positive slope light exit surface 322d, and a second negative slope light exit surface 322e.

In some embodiments, the boundary point between the first positive slope light exit surface 322a and the first negative slope light exit surface 322b is set to be a refracted light having an angle of zero with respect to the vertical direction after the light is refracted by the first sub-light incident surface 321a. The corresponding light-emitting surface position; the boundary point between the first negative-slope light-emitting surface 322b and the plane 322c is set to be a refracted light in a negative slope direction with the largest angle between the light and the vertical direction after the light is refracted by the second sub-light-incident surface 321b. Corresponding illuminating surface position; the boundary point 322c of the plane 322c and the second positive slope illuminating surface 322d is disposed after the ray is refracted by the second sub-lighting surface 321b. a position of the light exit surface corresponding to the refracted ray in the positive slope direction having the largest angle with the vertical direction; a boundary point of the second positive slope light exit surface 322d and the second negative slope light exit surface 322e is set in the light passing through the third sub-light After the surface 321c is refracted, the position of the light-emitting surface corresponding to the refracted ray having an angle of zero with respect to the vertical direction. The boundary point 1 and the boundary point 2 are respectively symmetric with the boundary point 4 and the boundary point 3.

As shown in FIG. 10, the first positive slope light exit surface 322a, the first negative slope light exit surface 322b, the second positive slope light exit surface 322d, and the second negative slope light exit surface 322e are designed to ensure refraction after refraction through the entrance surface. The largest refracted ray of the angle, when exiting through the illuminating surface, the outgoing ray can be perpendicular to the illuminating surface, thereby ensuring that the refracting angle does not become large when the light enters the opaque medium from the optically dense medium.

A light-emitting device for providing a backlight according to the embodiment provides an optical alignment device disposed above the light-emitting source of the light-emitting device according to the Raman invariance in the optical device, and the collimator of the optical collimating device The light surface is set to the negative slope into the light surface, the plane, and the positive slope into the light surface, thereby increasing the exit aperture of the light and reducing the light exit angle; on the other hand, the light exit surface is set to a positive slope at a specific position. The surface and the negative slope light-emitting surface, so that the refracted light having the largest refraction angle after being refracted by the light-incident surface is perpendicular to the light-emitting surface when exiting through the light-emitting surface, thereby ensuring the angle of refraction when the light enters the light-diffusing medium from the light-tight medium. It does not become large, and thus achieves a small angle of light output from the backlight, achieving a certain degree of collimation of light.

In some embodiments, in order to reduce the possibility of ray crosstalk between the respective sub-pixels, the divergence angle φ1 of the light emitted from the liquid crystal layer needs to satisfy the formula: φ1 ≤ arctan (L/H1), as shown in FIG. The width of the black matrix between the sub-pixel units, and H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer. In some embodiments, when the widths of the black matrices are different, L is the minimum width of the black matrix between each sub-pixel unit.

As can be seen from the above formula, in order to reduce the possibility of ray crosstalk between sub-pixels, one solution is to maximize the maximum effective range of the divergence angle φ1 of the outgoing ray, and another solution is to emit light from the liquid crystal layer. The divergence angle is limited to a small range.

In order to maximize the maximum effective range of the divergence angle φ1 of the outgoing light, according to the above formula, the width L of the black matrix between the sub-pixel units can be increased, or the upper surface of the liquid crystal layer can be reduced to the quantum dot color pixel layer. The height H1 of the lower surface. In a higher resolution liquid crystal panel such as 4K or 8K, the area ratio of the black matrix has become a key factor affecting the display efficiency of the above high resolution liquid crystal panel. The display brightness is a technical bottleneck that needs to be broken, and the width of the black matrix must be Controlling below 100um, even pursuing the preparation process below 20um.

In some embodiments, in order to reduce the height H1 of the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer, it is limited by the bottleneck of the existing polarizing plate preparation process and material, and generally H1 is 100-900 um. If a polarizing plate having a thickness of 100 μm or less is prepared, it is necessary to break through the technical bottleneck of the preparation materials and processes of the existing polarizing plate, even if the material and work thereof are prepared. There is a major breakthrough in art and even structure. Compared with the continuous improvement of the black matrix to reduce the width, the range of the maximum value of the divergence angle φ1 of the extended outgoing light is limited, and therefore, the divergence angle of the light emitted from the liquid crystal layer is limited. Limiting to a smaller range is an effective solution.

Therefore, after extensive research and development experiments, an effective solution for effectively reducing the divergence angle φ1 of light emitted from the liquid crystal layer has been sought. Among them, during the experiment, the relationship between display resolution, display brightness and light emission divergence angle φ1 is found, which has a very complicated effect on color crosstalk, and is not a linear relationship that can be known through simple reasoning. For example, when the resolution of the liquid crystal panel is increased, the display brightness is lowered due to the relative increase in the area ratio of the black matrix. Under this condition, the above-mentioned L and H1 are not changed according to the conventional logic, and therefore, the maximum possible value of φ1 is not There will be changes, and the crosstalk rate will not change. However, in actual experiments, it is found that the color crosstalk problem is aggravated when the display resolution is increased to a certain extent, indicating that the maximum value range of the divergence angle φ1 of the outgoing light is relatively reduced.

In some embodiments, in some solutions using a divergence angle φ1 that reduces the amount of light exiting the liquid crystal layer, it is found during the experiment that the brightness uniformity of the display is apparent when the divergence angle φ1 of the exiting light of the liquid crystal layer is reduced. Deterioration. Therefore, in the course of the experiment, the contradiction between maintaining the uniformity of display brightness of the liquid crystal panel and increasing the divergence angle φ1 of the light emitted from the liquid crystal layer becomes another technical problem that needs to be solved.

As shown in FIG. 3, a dot-type light-emitting device is used as a direct-type backlight module of the light-emitting device 230. The light-emitting device 230 is disposed under the liquid crystal panel, such as an LED light-emitting device. In order to achieve uniform illumination of the liquid crystal layer, it is required that a plurality of LED light-emitting devices are irradiated to the liquid crystal layer to have better light mixing characteristics.

As shown in FIG. 3, when the light of the LED light-emitting device is incident on the lower surface of the liquid crystal panel, the light divergence angle φ2 needs to satisfy φ2 ≥ arctan (0.5*D/H2), where D is two adjacent light-emitting devices. The center-to-center spacing of the light-emitting surfaces, H2 is the distance from the light-emitting surface of any of the light-emitting devices to the lower surface of the liquid crystal panel.

In summary, on the one hand, in order to reduce the color crosstalk between the color sub-pixels, it is necessary to reduce the divergence angle of the light emitted from the upper surface of the liquid crystal layer, and on the other hand, to maintain the illumination on the lower surface of the liquid crystal panel. For uniformity, it is necessary to increase the divergence angle of the light emitted from the light-emitting device. Therefore, in order to solve the technical contradiction between the two aspects, to break through the bottleneck of the technology, when the light of the light-emitting device is incident on the liquid crystal panel at a divergence angle φ2, it is necessary to satisfy arctan (0.5*D/H2) ≤ φ2 ≤ arctan (L/H1).

In some embodiments, when L=20um, H1=100um, arctan(L/H1)=11.3°, then the maximum divergence angle when the light of the light emitting device is emitted from the upper surface of the liquid crystal layer needs to be 0≤φ1≤ Value in the range of 11.3°. And in order to improve the display uniformity of the panel, φ2 takes the maximum value in the range of φ1, so that φ2 can be 11.3°, that is, let arctan (0.5*D/H2)=11.3°, then D The maximum value of /H2 is 0.4, which can provide a basis for designing the light mixing distance of the backlight module and the lamp spacing parameter. Designers can range from D/H2 ≤ 0.4 Inside, select the appropriate brightness specifications of the LED light-emitting device to meet the brightness design requirements, and select the appropriate divergence angle of the LED light-emitting device, or a suitable backlight structure to limit the divergence angle of the outgoing light, and rationally design the LED light-emitting device based on the above selection. The lamp spacing D and the light mixing distance H2 between the light emitting device and the lower surface of the liquid crystal panel to achieve the maximum possible optimization of product display performance.

In some embodiments, when selecting a liquid crystal panel in a product design process, how to design a backlight module that satisfies performance requirements for the liquid crystal panel is generally a technical problem that needs to be practically solved.

The first step: the maximum possible divergence angle φ1max of the light emitted from the liquid crystal layer needs to be determined by the parameters of the liquid crystal panel, that is, the relationship of φ1max=arctan(L/H1) is satisfied.

The second step: making the light-emitting device light incident on the liquid crystal layer with a divergence angle φ2 ≤ φ1max, that is, satisfying φ2 ≤ arctan (L/H1).

The third step: Since the minimum value of φ2 is determined by arctan (0.5*D/H2), it is necessary to satisfy arctan(0.5*D/H2)≤arctan(L/H1), namely: D/H2≤2* L/H1.

In this embodiment, L is the width of the black matrix between each sub-pixel, and H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer, and the parameters L and H1 which can be determined by the liquid crystal panel are expressed by the formula D/ H2 ≤ 2 * L / H1 to determine the light mixing characteristics of the backlight module, the mixed light characteristic is the relationship between the parameters D and H2, where D is the center-to-center spacing of the adjacent two light-emitting devices, and H2 is any light-emitting device The distance from the light emitting surface to the lower surface of the liquid crystal panel.

In some embodiments, as shown in FIG. 4, in order to ensure the uniformity of the illumination of the receiving surface, the illumination ranges of the adjacent two light-emitting devices on the receiving surface must have a certain overlapping range, as shown in the B region in the figure.

4 is used as an example to illustrate that when a single light-emitting device directly illuminates a liquid crystal panel, the illuminance of a target point on the liquid crystal panel is proportional to the light-emitting intensity of the light-emitting device, and the surface of the light-emitting device is to the target point. The square of the distance is inversely proportional to the cosine of the angle between the normal of the light-emitting surface of the light-emitting device and the illumination beam of the target point, that is, the illumination illuminance E(φ) of the target point satisfies the formula: E(φ)= I(φ)*cosφ/d ² , where I(φ) is the light intensity distribution of the light emitting device, φ is the angle formed by the normal line of the light emitting surface of the light emitting device and the light beam of the target point, and d is the light emission The distance from the light emitting surface of the device to the target point.

As shown in FIG. 4, in some embodiments, a point of optical illumination in region A: E(φ)=I(φ)*cosφ/d ² , where d=H/cosφ, H is the light emitting surface of the light emitting device and the The distance between the lower surfaces of the liquid crystal panels, therefore, E(φ)=I(φ)*cosφ/d ² =I(φ)*cos ³ φ/H ^{2 can be obtained} .

The example in which the display uniformity requirement is 70% or more is described as follows. If the uniformity of the entire light receiving surface is required to satisfy 70% or more.

On the one hand, if the position of the light receiving surface where the center line of the connection between the two light emitting devices is opposite is a dark light region, Then, the illuminance of the single light-emitting device received by the light-emitting device needs to reach more than 35% of the illuminance E0 of the light-emitting surface corresponding to the light-receiving surface of the light-emitting device, so that the superimposed illuminance of the two light-emitting devices at the center of the connection line can be Reach 70% or more of E0.

Then, the following conditions must be met: E(φ)≥0.5*70%*E(0°), ie: I(φ)*cos3φ/H≥0.35*I(0°)/H2, simplified: I(φ) *cos ³ φ ≥ 0.35 * I (0°), and the maximum value φmax of φ can be obtained from the above equation, and I(φmax)*cos ³ φmax=0.35*I(0°).

On the other hand, when the position of the light receiving surface where the center position of the two light-emitting devices is opposite is the light-emitting area, the illuminance E0 of the light-emitting device corresponding to the receiving surface is 0, and the connection of the two light-emitting devices is required. The illuminance at the position of the receiving surface where the center of the line is directly opposite is 70% or more.

Then the following conditions must be met: E(φ)≤0.71*E(0°), ie: I(φ)*cos3φ/H2≤0.71*I(0°)/H2, simplified: I(φ)*cos3φ≤ 0.71*I (0°), the minimum value φmin of φ can be obtained from the above equation, then I(φmin)*cos3φmin=0.71*I(0°).

In summary, if the light intensity distribution of the light emitting device is I(φ), and the display uniformity requires a% or more, the two light emitting devices correspond to the target on the receiving surface of the one element at the center position at the connection. at the point the light beam emission angle is φ, then satisfies the ^{equation: I (φmax) * cos 3} φmax = 0.5 * a% * I (0 °), and ^{I (φmin) * cos 3 φmin} = 0.5 / a% * I (0 °).

In some embodiments, if the LED light emitting device is taken as an example, the illuminating energy of the LED illuminating device is a Lambertian distribution, and I(φ)=I ₀ *cos φ, where I ₀ is the 0° directional light of the illuminating light. A strong value, which is a fixed value, the illuminance distribution of the receiving surface receiving a single LED light emitting device is E(φ)=I(φ)*cos ³ φ/H=I ₀ *cos ⁴ φ/H.

Taking FIG. 3 as an example, if the uniformity of the receiving surface is 70% or more, it is necessary to satisfy:

E(φ1)≥35%*E(0°), that is, cos4φ1≥0.35, and φ1max≈39.5° is obtained, then 0.5*D/H2≤tan39.5°≈0.82, that is, D/H2≤1.64.

And E(φ1)≤0.71%*E(0°), that is, cos4φ1≤0.71, and φ1min≈23.5° is obtained, then 0.5*D/H2≥tan23.5°≈0.43, that is, D/H2≥0.86.

Therefore, if the illuminating energy of the illuminating device is a Lambertian distribution, the light mixing characteristic of the backlight module needs to satisfy: 0.86 ≤ D / H2 ≤ 1.64, where D is the center-to-center spacing of the light-emitting surfaces of two adjacent light-emitting devices, and H2 is The distance from the light emitting surface of a light emitting device to the lower surface of the liquid crystal panel.

It should be noted that, in some embodiments of the present application, only the requirements of the light mixing characteristics of the backlight module need to be met, that is, the color crosstalk between the color sub-pixels can be reduced, and the liquid crystal panel can be kept facing the liquid crystal panel. The following table The purpose of uniformity of illumination on the surface.

As shown in FIG. 2 , in order to further improve the illumination uniformity of the light-emitting device 230 on the liquid crystal panel, and to reduce the incident angle of the light incident on the liquid crystal layer as much as possible, to reduce the cross-interference between the pixels, the embodiment of the present application In the liquid crystal display device, an optical collimating device for collimating the light emitted from the light emitting device is disposed, and diffusion of light energy from the optical collimating device is performed to achieve uniform diffusion, so that the illuminance on the light receiving surface is more uniform The distribution is such that the D/H ₂ value is increased by 2 to 3 times or more. Therefore, in a liquid crystal display device using an optical alignment device, 1.72 ≤ D/H ₂ ≤ 4.92 can be satisfied.

The optical collimating device is used for an optical device that converts divergent rays into nearly parallel rays, such as a convex lens or the like.

It should be noted that, in the liquid crystal display device for increasing the collimation processing of the light emitted from the light emitting device, on the one hand, the light emitting device can be designed with a larger design space, and the energy distribution of the light emitted from the light emitting device is diffused and homogenized. The display uniformity of the liquid crystal display device is improved. On the other hand, since the light emitted from the light emitting device is collimated, the divergence angle of the light emitted from the liquid crystal layer becomes small, and the color crosstalk problem between the pixels can be reduced.

In some embodiments, the parameters of the optical alignment device are as follows. As shown in FIG. 3, after the light from the light-emitting device is collimated by the optical collimating device, the light exit angle φ3 needs to satisfy: φ3 ≤ arctan (L/ H1), where L is the width of the black matrix between the sub-pixels, and H1 is the height of the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.

In one embodiment of the present application, in order to improve display uniformity or increase the value of the light mixing characteristic D/H2, the light of the light emitting device may be pre-diffused, and a light diffusing lens such as a concave lens may be disposed on the light emitting device. . And a light collimating lens for collimating the diffused light, wherein the collimating angle φ3 of the collimating lens needs to satisfy the requirement of the formula φ3 ≤ arctan (L/H1), where L is the width of the black matrix, and H1 is The height of the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.

An embodiment of the present application provides another liquid crystal display device, wherein the liquid crystal panel portion of the liquid crystal display device in this embodiment is the same as the above embodiment, and will not be described again. In addition, in this embodiment, a backlight module for diffusing the light emitting device is further provided. As shown in FIG. 11, the light emitting device has the characteristics of small divergence angle and high collimation degree, such as laser light emission. The device, or a light-emitting device with a collimating lens disposed above the LED, the backlight module specifically includes a light-emitting device 21 and a beam expander, and the beam expander expands and collimates the light emitted by the light-emitting device. The light emitting device 21 is a plurality of spaced-apart devices for providing backlighting devices for the backlight module.

The beam expander includes an input negative lens and an output positive lens. Among them, a negative lens such as a concave lens and an output positive lens such as a convex lens are input.

Wherein, the input negative lens in the beam expander can expand the light of the light emitting device, improve the spot diameter of the light beam of the light source of the point light source, and increase the possibility of overlapping light of the light emitting devices of the plurality of point light sources to improve the display uniformity. Sex.

In some embodiments, as shown in FIG. 12, in the present embodiment, a beam expanding plate 22 may be disposed above the light emitting device 21, and as shown in FIG. 13, a collimating plate 23 is disposed above the beam expanding plate 22. A plurality of input negative lenses 225 are disposed on the beam expanding plate 22 corresponding to the plurality of light emitting devices, and a plurality of output positive lenses 231 are disposed on the collimating plate 23 corresponding to the plurality of light emitting devices.

In some embodiments, if the image focus of the input negative lens 225, the object focus of the output positive lens 231, and the center of the light emitting device 21 are coincident, the outgoing light of the light emitting device 21 is sequentially passed through the beam expanding plate 22. The negative lens 225 and the output positive lens 231 on the collimator 23 are input to effect diffusion of the light emitted from the light-emitting device 21 and further collimation. According to the principle, the light emitted from the focus of the lens passes through the lens and the light is emitted in parallel. According to this principle and the principle of reversible optical path, if the image focus of the concave flat lens coincides with the object focus of the plano-convex lens, the parallel light passes through the concave After the flat lens is diverged, it is still emitted in parallel after passing through the plano-convex lens, and can be understood by those skilled in the art according to the working principle of the lens, and will not be described in detail in this embodiment.

In some embodiments, the input negative lens 225 is designed as a concave lens according to the working principle of the lens and the characteristic that the outgoing light of the light emitting device 21 is approximately parallel, that is, the input negative lens 225 includes a first sub-light entering the concave side of the light incident surface. The surface of the light-emitting surface is a plane first light-emitting surface; the output positive lens 231 is designed as a convex lens, that is, the output positive lens 231 includes a second sub-light-incident surface on the side of the light-incident surface, and the side of the light-emitting surface is convex. The second illuminating surface.

The light emitted from the light-emitting device 21 sequentially passes through the first sub-light-incident surface which is a concave surface and the first light-emitting surface which is a flat surface, so as to realize the divergence of the light-emitting device 21, and effectively increase the light emission when the number of the light-emitting devices 21 is small. The device 21 emits a range of light, and then the diverged light-emitting device 21 ray sequentially passes through the second sub-light-incident surface which is a plane and the second light-emitting surface which is a convex surface, thereby achieving collimation of the light-emitting device 21.

In some embodiments, in order to utilize the light-emitting device 21 efficiently, the size of the light-emitting device 21, the size of the input negative lens 225, and the size of the output positive lens 231 are sequentially increased, so that all of the outgoing light of the light-emitting device 21 passes through the beam expanding plate 22. The input negative lens 225 structure, that is, when the concave surface of the first sub-light incident surface of the beam expanding plate 22 is disposed, it should be ensured that the light emitting range of the light emitting device 21 is smaller than the concave surface of the first sub-light incident surface.

And after the light of the light-emitting device 21 is diverged by the input negative lens 225, the light of the light-emitting device 21 is converted from the original parallel light into the scattered light emitted from the self-scattering lens, so that the emission range of the scattered light is significantly larger than the initial light. Similarly, in order to increase the utilization of the scattered light, it is ensured that the scattered light rays are all incident on the output positive lens 231 on the collimating plate 23, and the concave surface on the first sub-incident surface is smaller than the convex surface on the second luminous surface.

In some embodiments, in order to achieve a one-to-one correspondence between the concave surface of the first sub-light incident surface and the convex surface of the second light-emitting surface, the illumination device provided by the backlight module is uniform and minimized. The number of the light-emitting devices 21 is a plurality of the light-emitting devices 21 in the embodiment. The corresponding ones of the input negative lens 225 and the output positive lens 231 are evenly spaced. The specific number should be based on the liquid crystal panel. The size, and the size of the concave surface on the first sub-light incident surface of the beam expanding plate 22, and the setting size of the convex surface on the second light emitting surface of the collimating plate 23 are set, and finally, the laser light emitting device is minimized to realize the entire display. The screen provides the purpose of a backlighting device.

In some embodiments, also to reduce the light loss of the light-emitting device 21 after the beam expander 22 and the collimator 23, the material of the beam expander 22 and the collimator 23 includes a high optical transmittance (PMMA). Material, polycarbonate (PC) material.

The embodiment provides a display device, including a liquid crystal panel and a backlight module, wherein the backlight module includes a light emitting device, a beam expander plate and a collimating plate which are sequentially disposed above the light emitting device, and the beam expander plate is set by the corresponding light emitting device. The input negative lens is configured to diffuse the light emitting device; the collimating plate is composed of an output positive lens disposed corresponding to the light emitting device for collimating the light emitting device; the image focus of the negative lens is input, and the positive lens is output The square focus and the center of the light-emitting device coincide. In the backlight module provided in this embodiment, a diffusing plate and a collimating plate having diffusion effects are sequentially disposed above the light emitting device. In some embodiments, the beam expanding plate is composed of an input negative lens having a light scattering effect, and the collimating plate It consists of an output positive lens with light collimation. Due to the light diffusion effect of the input negative lens and the light collimation of the output positive lens, and the number of light-emitting devices is small, the light is first diffused by inputting a negative lens to increase the emission range of the laser light, and then passed through the output positive lens pair. The scattered light after the light is diffused is collimated to ensure that the light is emitted in parallel, thereby solving the color crosstalk problem occurring in the liquid crystal panel.

An embodiment of the present application provides a modification of another liquid crystal display device. As shown in FIG. 14 , the light emitting device of the embodiment has a small divergence angle and a relatively high degree of collimation, such as a collimating lens disposed above the LED. The light-emitting device specifically includes a light-emitting device 31 and a beam expander, and the beam expander expands and collimates the light emitted from the light-emitting device. The light emitting device 31 is a plurality of spaced-apart devices for providing backlighting devices for the backlight module.

In some embodiments the light emitting device 31 is a laser light emitting chip.

A collimating lens 34 is disposed above the light emitting device 31 for collimating the light emitted from the light emitting device.

In some embodiments, as shown in FIG. 14, in the present embodiment, a beam expanding plate 32 may be disposed above the light emitting device 31, and a collimating plate 33 may be disposed above the beam expanding plate 32. A plurality of input negative lenses are disposed on the beam expanding plate 32 corresponding to the plurality of light emitting devices, and a plurality of output positive lenses are disposed on the collimating plate 33 corresponding to the plurality of light emitting devices.

The portion of the beam expander in this embodiment is the same as that of the above embodiment, and will not be described again.

One embodiment of the present application provides a modification of another liquid crystal display device, and the liquid crystal display device of the present embodiment, Also includes:

a light diffusing lens; wherein the optical collimating device is a light collimating lens; the light diffusing lens is disposed on the light emitting source, and the collimating lens is disposed above the light diffusing lens, and the collimating angle φ3 of the light collimating lens needs to satisfy the formula φ3 ≤ arctan (L/H1) requires that L be the width of the black matrix, and H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.

The light diffusing lens expands the emitted light of the light source, and the light collimating lens collimates the exiting light of the light diffusing lens.

In some embodiments, the light diffusing lens is an input negative lens; the light collimating lens is an output positive lens.

In some embodiments, the image focus of the input negative lens, the object focus of the output positive lens, and the center of the illumination source are within a desired preset range.

In some embodiments, the input negative lens includes a first sub-light incident surface having a concave surface on one side of the light incident surface, a first light output surface having a plane on one side of the light exit surface, and a first plane on the side of the light incident surface. The second sub-light surface is a second light-emitting surface on the side of the light-emitting surface.

In some embodiments, the size of the illuminating light source, the size of the input negative lens, and the size of the output positive lens sequentially increase.

The embodiment provides a display device, including a liquid crystal panel and a backlight module. The backlight module includes a light emitting device, and the light emitting device includes a light emitting source, a light diffusing lens disposed on the light emitting source, and a light disposed above the light diffusing lens. A collimating lens, a light diffusing lens for diffusing the illuminating light source, and a light collimating lens for collimating the illuminating light source. Due to the light diffusion effect of the light diffusing lens and the light collimation of the light collimating lens, and the number of light emitting devices is small, the light is first diffused by the light diffusing lens to increase the range of the laser light, and then collimated by the light. The lens collimates the scattered light after the light is diffused to ensure that the light is emitted in parallel, thereby solving the color crosstalk problem occurring in the liquid crystal panel.

In summary, the present application provides a liquid crystal display device including a liquid crystal panel including a quantum dot color pixel layer, an upper polarizing plate, a liquid crystal switching unit, and a lower polarizing plate which are sequentially stacked. The quantum dot color pixel layer includes a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit. The display device further includes a backlight module disposed under the liquid crystal panel, the backlight module including a back plate and a light emitting device disposed thereon, the light emitting device comprising an LED light emitting device and an optical collimating device disposed thereon. According to the Lach invariant, by setting an optical alignment device above the LED light-emitting device, the light exit aperture is increased, so that the light-emitting angle of the backlight is reduced, and the light achieves a certain degree of collimated emission, thereby improving the liquid crystal panel in the pair. When the screen is displayed, the angle of the backlight is large. Color crosstalk between pixels.

It should be noted that the above embodiments are only used to illustrate the technical solutions summarized in the present application, and are not limited thereto; although the present application is described in detail with reference to the foregoing embodiments, those skilled in the art should understand The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the essence of the corresponding technical solutions. The scope of the technical solution.

Claims

A liquid crystal display device comprising a liquid crystal panel and a backlight module, wherein the liquid crystal panel comprises: a liquid crystal layer, and an upper polarizing plate and a lower polarizing plate are disposed on the upper side and the lower side of the liquid crystal layer, and quantum dot color pixels are arranged Layer, characterized in that

The quantum dot color pixel layer is disposed above the upper polarizing plate;

The backlight module includes a back plate, an illuminating light source disposed on the back plate, and an optical collimating device disposed above the illuminating light source.
A liquid crystal display device according to claim 1, wherein said optical collimating means comprises a support frame and a collimator disposed between said support frames, said collimator comprising a light incident surface and a light exiting surface.
The liquid crystal display device according to claim 2, wherein the light incident surface of the collimator is a convex surface.
The liquid crystal display device according to claim 2 or 3, wherein the light incident surface sequence includes a first light incident surface having a negative slope, a second light incident surface having a slope of zero, and a third positive slope Into the glossy surface.
The liquid crystal display device according to claim 4, wherein the angle between the first light incident surface and the inner surface of the support frame satisfies: after the light is incident through the first light incident surface, Emitting the light exiting surface, the maximum angle of the outgoing light rays in the positive slope direction and the normal line at the light exiting position where the light emitting surface exits the light in the positive slope direction, and the outgoing light rays in the negative slope direction The maximum angle of the normal line at the light exiting position where the light exiting the light exiting in the negative slope direction is the same, and the maximum angle is equal to the angle formed by the incident light rays passing through the two ends of the second light incident surface. Half of it.
The liquid crystal display device according to claim 2 or 3, wherein the light-emitting surface is a convex surface or a flat surface.
The liquid crystal display device according to claim 2 or 3, wherein the light-emitting surface sequence comprises a first positive slope light-emitting surface, a first negative-slope light-emitting surface, a plane, a second positive-slope light-emitting surface, and a second negative slope Glossy.
The liquid crystal display device according to claim 7, wherein the first boundary point of the first positive slope light emitting surface and the first negative slope light emitting surface is disposed after the light is refracted through the first light incident surface a position of the light-emitting surface corresponding to the refracted ray having an angle of zero with respect to the vertical direction; the second boundary point of the first negative-slope light-emitting surface and the plane is disposed after the light is refracted through the second light-incident surface a position of the light exiting surface corresponding to the refracted ray in the negative slope direction having the largest angle with the vertical direction; a third boundary point of the plane and the second positive slope light exiting surface, and the second positive slope light emitting surface The fourth boundary point 4 of the second negative slope light-emitting surface is symmetrically disposed with the second boundary point 2 and the first boundary point, respectively.
The liquid crystal display device according to claim 2 or 3, wherein the light incident surface and the light output The faces are circumferentially symmetrical.
The liquid crystal display device according to any one of claims 1 to 3, wherein the quantum dot color pixel layer comprises a plurality of color sub-pixel units arranged in phase and black between the sub-pixel units a matrix; the multi-color sub-pixel unit includes a red sub-pixel unit, a green sub-pixel unit, and a blue sub-pixel unit.
The liquid crystal display device according to any one of claims 1 to 10, further comprising:

Beam expander

The beam expanding structure is used to expand and collimate the outgoing light of the optical collimating device.
A liquid crystal display device according to claim 11, wherein a divergence angle of the light after the beam expanding mirror is collimated
Need to satisfy the formula
It is required that L is the width of the black matrix, and H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.
The liquid crystal display device according to claim 11 or 12, wherein the beam expander includes a plurality of negative lenses and a plurality of positive lenses provided corresponding to the light emitting device.
The liquid crystal display device according to claim 13, wherein an image-side focal point of said negative lens, an object-side focus of said positive lens, and a center of said light-emitting device are within a desired preset range.
The liquid crystal display device according to claim 13, wherein the negative lens includes a first sub-light incident surface having a concave surface on a light incident surface side, and a first light exit surface having a flat surface on a light exit surface; The lens includes a second sub-light incident surface that is planar on one side of the light incident surface, and a second light exit surface that is convex on one side of the light exit surface.
The liquid crystal display device according to claim 13, wherein the size of the illuminating light source, the size of the negative lens, and the size of the positive lens are sequentially increased.
A liquid crystal display device according to claim 13, wherein a plurality of said negative lenses are formed on a beam expander plate, and a plurality of said positive lenses are formed on a collimator plate.
The liquid crystal display device according to claim 17, wherein the material of the beam expander plate and the collimator plate comprises a PMMA material or a polycarbonate (PC) material having a high optical transmittance.
The liquid crystal display device according to any one of claims 1 to 18, wherein the illuminating light source is a laser light emitting chip.
The liquid crystal display device according to claim 19, wherein the optical alignment device disposed above the laser light emitting chip is a collimating lens.
The liquid crystal display device according to any one of claims 1 to 10, further comprising:

a light diffusing lens; wherein the optical collimating device is a light collimating lens; the light diffusing lens is disposed on the light emitting source, the collimating lens is disposed above the light diffusing lens, and the light is collimated Collimation of the lens The angle φ3 needs to satisfy the requirement of the formula φ3 ≤ arctan (L/H1), L is the width of the black matrix, and H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.
The liquid crystal display device according to claim 21, wherein the light diffusing lens is a negative lens; and the light collimating lens is a positive lens.
The liquid crystal display device according to claim 21, wherein the image focus of the negative lens, the object focus of the positive lens, and the center of the illuminating light source are within a desired preset range.
The liquid crystal display device according to claim 21, wherein the negative lens comprises a first sub-light incident surface having a concave surface on a light incident surface side, and a first light exit surface having a flat surface on a light exit surface; The lens includes a second sub-light incident surface that is planar on one side of the light incident surface, and a second light exit surface that is convex on one side of the light exit surface.
The liquid crystal display device according to claim 21, wherein the size of the illuminating light source, the size of the negative lens, and the size of the positive lens are sequentially increased.
The liquid crystal display device according to claim 10, wherein

The light mixing characteristic of the backlight module satisfies the requirement of the formula D/H2≤2*L/H1, D is the center distance of the light emitting surfaces of two adjacent optical collimating devices, and H2 is any of the optical collimating devices. The distance from the light emitting surface to the lower surface of the liquid crystal panel, L is the width of the black matrix, and H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.
The liquid crystal display device according to claim 10, wherein the divergence angle φ1 of the light emitted from the liquid crystal layer needs to satisfy the requirement of φ1 ≤ arctan (L/H1), L is the width of the black matrix, and H1 is The height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.
The liquid crystal display device according to claim 10, wherein the light mixing characteristic of the backlight module needs to satisfy the formula: 1.72 ≤ D / H 2 ≤ 4.92, wherein D is two adjacent optical standards The center distance of the light emitting surface of the straight device, and H2 is the distance from the light emitting surface of any of the optical collimating devices to the lower surface of the liquid crystal panel.
The liquid crystal display device according to claim 28, wherein

The light mixing characteristic of the backlight module needs to satisfy the formula: 0.86≤D/H2≤1.64, where D is the center distance of the light emitting surfaces of two adjacent optical collimating devices, and H2 is any optical standard The distance from the light emitting surface of the straight device to the lower surface of the liquid crystal panel.
The liquid crystal display device according to claim 10, wherein a divergence angle φ3 of the collimated light from the optical collimating device satisfies a requirement of a formula φ3 ≤ arctan (L/H1), wherein L is the The width of the black matrix, H1 is the height from the upper surface of the liquid crystal layer to the lower surface of the quantum dot color pixel layer.
The liquid crystal display device according to any one of claims 12, 21, 26, 27 or 30, wherein

The L is the smallest width in the black matrix.
The liquid crystal display device according to any one of claims 1 to 3, wherein the backlight module is a direct type backlight module in which the light emitting source is arranged in a dot pattern below the liquid crystal panel.
The liquid crystal display device according to claim 10, wherein the red sub-pixel unit is provided with a red quantum dot material, the green sub-pixel unit is provided with a green quantum dot material, and the blue sub-pixel unit is packaged with a blue color. The quantum dot material directly transmits blue light, and the number of the red sub-pixel unit, the green sub-pixel unit, and the blue sub-pixel unit is plural.