CN113467129A

CN113467129A - Optical plate and display device comprising same

Info

Publication number: CN113467129A
Application number: CN202110742342.0A
Authority: CN
Inventors: 罗飞
Original assignee: Najing Technology Corp Ltd
Current assignee: Najing Technology Corp Ltd
Priority date: 2021-06-30
Filing date: 2021-06-30
Publication date: 2021-10-01
Anticipated expiration: 2041-06-30
Also published as: CN113467129B

Abstract

The present disclosure provides an optical plate and a display device. The optical plate is internally provided with a plurality of reflectors which are perpendicular to the bottom surface of the optical plate, the reflectors are regularly arranged in an array mode, each reflector divides the optical plate to form a plurality of optical areas, and the optical plate is used for being optically connected with a plurality of backlight light sources controlled in a subarea mode. The optical plate has the advantages that the light ray blocking effect of the reflecting piece of the optical plate forms a plurality of optical areas, secondary partition of the backlight light source is realized, light leakage is reduced, and accordingly the contrast ratio of the image edge is improved.

Description

Optical plate and display device comprising same

Technical Field

The disclosure relates to the field of backlight display, in particular to an optical plate and a display device comprising the same.

Background

The liquid crystal display is limited by the phenomenon of pixel light leakage, and compared with a novel display technology, the contrast ratio is a short plate, so that a subarea backlight method is gradually developed for the liquid crystal display technology, a backlight source LED is regulated and controlled in subareas, backlight with different brightness is respectively regulated and controlled in a high gray level area and a low gray level area, the pixel light leakage phenomenon can be improved to a certain extent, and the display contrast ratio is improved. However, the display effect of the backlight source partition regulation and control technology is positively correlated with the number of partitions, the more partitions are, the more difficult the realization technology is, and the higher the cost is, and therefore, a more effective solution is needed.

Disclosure of Invention

The present disclosure is directed to an optical plate and a display device including the same, which efficiently reduce a pixel light leakage phenomenon of the display device due to insufficient backlight control, and improve contrast.

In order to achieve the above object, according to a first aspect of the present disclosure, there is provided an optical plate, in which a plurality of reflectors are disposed in an interior of the optical plate, the reflectors being arranged in a regular array, each reflector partitioning the optical plate to form a plurality of optical regions, and the optical plate is used for optically connecting a plurality of backlight sources controlled in different zones.

Further, the thickness of each reflecting member is 0.5mm or less, preferably 0.25mm or less.

Further, the reflectance of each reflecting member is not less than 50%, preferably not less than 80%.

Further, the orthographic projection of each optical area is rectangular, and the transverse length of each optical area is one or more; when there are multiple lateral lengths of each optical zone, optical zones of the same lateral length are not adjacent to each other.

Further, the orthographic projection shapes of the respective optical regions are the same, and preferably the orthographic projection areas are the same.

Further, the main body of the optical plate is made of resin material, and the optical plate further comprises quantum dot material, and the quantum dot material is dispersed in the resin material.

Further, the reflectivity of the reflecting member is gradually reduced in a direction away from the backlight light source.

Further, the optical plate includes a matrix of a resin material, the refractive index of the matrix gradually decreasing in a direction away from the backlight light source.

Further, the optical plate includes a matrix of a resin material and diffusion particles dispersed in the matrix, the concentration of the diffusion particles being gradually reduced in a direction away from the backlight light source.

Further, the optical sheet includes a plurality of diffusion layers stacked, and the refractive index of the matrix of the diffusion layers of the respective layers is gradually decreased in a direction away from the backlight light source.

Furthermore, the optical plate comprises two diffusion layers, the transverse lengths of the partitions of the backlight light source are both L, and the thickness of the optical plate is d; the refractive index of the matrix of the diffusion layer closest to the backlight light source is n₁The refractive index of the matrix of the diffusion layer furthest from the backlight source is n₂And n is₁>n₂，

1＜n₁/n₂＜2，L≥d。

Further, the air conditioner is provided with a fan,

according to a second aspect of the present disclosure, there is provided a display device, the display device comprising a plurality of backlight light sources controlled in a subarea, a display layer including a plurality of pixels, and any one of the optical plates described above, wherein an orthographic projection area of a subarea of the backlight light source is larger than an orthographic projection area of any one of the optical areas; when the display device is operated, light of the backlight light source reaches the display layer through the optical plate, and the pattern is displayed through the display layer.

Further, the thickness of each reflector is less than or equal to 1 pixel point, preferably less than or equal to 0.5 pixel point, and more preferably less than or equal to 0.1 pixel point.

Further, the orthographic projection of each optical area is rectangular, and the transverse length of the subarea of each backlight light source is larger than that of each optical area.

Further, the orthographic projection of each reflecting member does not cover the division line of the partition of each backlight light source.

Furthermore, the display device is a direct type display device, and the optical plate is a diffusion plate; or the display device is a side-in type display device, and the optical plate is a light guide plate.

By applying the technical scheme, due to the light ray blocking effect of the reflecting piece of the optical plate, a plurality of optical areas are formed, secondary partition of the backlight light source is realized, light leakage is reduced, and the contrast ratio of the image edge is improved. The display device adopting the optical plate has higher display contrast.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, illustrate exemplary embodiments of the disclosure and, together with the description, serve to explain the disclosure and not to limit the disclosure. In the drawings:

fig. 1 shows a schematic cross-sectional structure and a schematic display effect of a direct type display device in the prior art.

Fig. 2 is a schematic diagram showing a cross-sectional structure and a display effect of a direct type display device in another prior art.

Fig. 3 is a schematic cross-sectional view illustrating a direct type display device according to an embodiment of the invention.

Fig. 4 is a schematic structural diagram illustrating a partitioned optical plate and a partitioned backlight light source of a direct-type display device according to an embodiment.

Fig. 5 is a schematic top view of a partitioned optical plate of a lateral display device according to an embodiment.

Fig. 6a is a schematic top view and fig. 6b is a schematic side view of a partitioned optical plate according to an embodiment.

Fig. 7 is a schematic top view of a partitioned optical plate according to an embodiment.

Fig. 8 is a schematic top view of a partitioned optical plate according to an embodiment.

Fig. 9 is a schematic cross-sectional view illustrating a display device according to an embodiment in which the refractive index of the optical plate is decreased.

Fig. 10 is a schematic cross-sectional view illustrating a display device according to an embodiment in which the refractive index of the optical plate is decreased.

Fig. 11 shows an image to be displayed of the display device of embodiment 1.

Fig. 12 is a diagram showing a backlight partition size of the display device of embodiment 1.

Fig. 13 shows an optical simulation display effect diagram of embodiment 1.

Fig. 14 shows a graph of the optical simulation display effect of comparative example 1.

Fig. 15 shows an optical simulation display effect diagram of comparative example 2.

Reference numerals: 1. a display layer; 2A, a conventional optical plate; 2B, a partitioned optical plate; 3A, a non-partitioned backlight source; 3B, partitioning backlight light sources; z1, light leakage area; z2, image display area set.

Description of abbreviations: BL is a backlight source.

Detailed Description

It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the disclosure. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.

It is noted that the terms "comprises" and "comprising," and any variations thereof, in the description and claims of this disclosure, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

Exemplary embodiments of the solutions provided according to the present disclosure will be described in more detail below. These exemplary embodiments may, however, be embodied in many different forms and should not be construed as limited to only the embodiments set forth herein. It is to be understood that these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of these exemplary embodiments to those skilled in the art.

In the prior art lcd device, the conventional optical plate is made of a whole piece of acrylic or other optical plastic material. As shown in fig. 1, if the backlight source partition control is not used, the light leakage is serious, and the pixels that do not need to be displayed emit light, so that the image edge is blurred. As shown in fig. 2, if the backlight light sources are used to control the on/off and brightness of the backlight light sources in different regions, since the optical path transmission can be performed inside the optical plate, in addition to the set image display region, the display layer directly above the backlight light sources BL1 and BL4 also receives the light from the backlight light sources BL2 and BL3 (see arrow directions, which refer to light ray directions), although the display effect of the design of fig. 2 is improved compared with that of fig. 1, the light leakage phenomenon of some pixels still occurs, which causes the edge of the image to be displayed to be blurred, and reduces the contrast.

According to a first aspect of the present disclosure, there is provided an optical plate, wherein a plurality of reflectors perpendicular to a bottom surface of the optical plate are disposed inside the optical plate, each reflector is regularly arranged in an array, each reflector partitions the optical plate to form a plurality of optical areas, and the optical plate is used for optically connecting a plurality of backlight sources controlled in zones. A plurality of optical areas are formed by utilizing the light blocking effect of the reflecting piece, so that secondary partition of the backlight light source is realized, light leakage is reduced, and the contrast ratio of the image edge is improved.

The shape of the orthographic projection of the optical zone is not limited and depends on the array arrangement of the reflectors. In some embodiments, the orthographic shape of the optical region is triangular, rectangular, pentagonal, hexagonal, octagonal, circular, or the like. In some preferred embodiments, the orthographic shape of the optical area is the same as the orthographic shape of the backlight light source partition. In some preferred embodiments, the orthographic shape of the optical area is the same as the pixel shape of the display device including the optical plate. In some embodiments, the reflectors are one or both of laterally aligned and longitudinally aligned. In some embodiments, the regular array arrangement of reflectors may be arranged with reference to a pixel array. In some embodiments, the forward projection areas of the respective optical regions are not identical.

In some embodiments, the zoning of the optical plate is as in fig. 6-8. If the partition distribution is thick (large area), the effect of slowing down light leakage is smaller than that of the thin partition distribution (small area).

In some embodiments, the preparation of the reflector within the optical plate may employ, but is not limited to, the following methods: (1) the initial optical plate is divided into a plurality of small plates and spliced with the reflecting piece, and splicing can be pasting; (2) when the optical plate is prepared by adopting an extrusion process, the reflector is embedded into the optical plate matrix and is synchronously solidified in the process of extruding and melting the optical plate matrix; (3) and cutting the initial optical plate according to the reflection distribution position, and injecting the reflecting piece colloid into the initial optical plate, and curing.

In some embodiments, the thickness of each reflector is 0.5mm or less, preferably 0.25mm or less. The presence of the thickness of the reflector reduces the light emission and hinders the light emission from the pixel, and therefore a thin reflector is preferable. The "thickness" here refers to the width of the cross section of the reflector.

In some embodiments, the material of each reflector is metal, metal compound, glass, high-reflective inorganic coating or colloid containing high-concentration scattering particles such as titanium dioxide, silicon dioxide, etc., and those skilled in the art can select the material according to the reflective effect.

In some embodiments, the reflectivity of each reflector is not less than 50%, preferably not less than 80%. The higher the reflectance, the better, and the light blocking effect is effectively achieved.

In some embodiments, the orthographic projection of each of the optical regions is rectangular, and the lateral length of each of the optical regions is one or more; when there are multiple lateral lengths of each optical zone, optical zones of the same lateral length are not adjacent to each other. The "lateral length" described in the present disclosure refers to the lateral length in cross section, for example "L" of fig. 10.

In some embodiments, the orthographic projection of each optical zone is the same shape, preferably the orthographic projection area is the same.

In some embodiments, the optical zones are distributed symmetrically in the optical plate. Therefore, when the display device is used for the display device, a picture which is symmetrically displayed can be displayed, namely, the picture with consistent light leakage degree can be obtained, and the display device is more attractive.

In some embodiments, the body of the optical plate is a resin material, the optical plate further comprising a quantum dot material, the quantum dot material being dispersed in the resin material. The quantum dot material may function as a light conversion. The optical sheet is not a quantum dot color film as understood by those skilled in the art. In some embodiments, the optical plate comprises a mixture of red and green quantum dot materials.

In some embodiments, the reflectivity of the reflector decreases gradually in a direction away from the backlight light source. So that the reflector can make the light and shade transition of the image edge light leakage more uniform. Such reflectors may be achieved by controlled gradual reduction of the concentration of reflective material in the gel in the longitudinal direction. The term "gradually" includes both equidifferent and non-equidifferent decrements.

In some embodiments, the optical plate comprises a matrix of a resin material, the refractive index of the matrix gradually decreasing in a direction away from the backlight light source. For example, in fig. 9, the light is focused toward the middle, and the effect of reducing the size of the original backlight light source partition, that is, the effect of increasing the partition, is achieved. To achieve this design, a variety of resin materials of different refractive indices are required.

In some embodiments, the optical plate includes a matrix of a resin material and diffusion particles dispersed in the matrix, a concentration of the diffusion particles gradually decreasing in a direction away from the backlight light source. Those skilled in the art can select the proper particle size and type of the diffusion particles according to the optical characteristics to be achieved by the optical plate. The diffusion particles scatter light, and secondary partition is performed on the light of the backlight light source after scattering, so that backlight energy of each partition of the optical plate is more uniform.

In some embodiments, the optical sheet comprises a plurality of stacked diffusion layers, the refractive index of the matrix of the diffusion layers of each layer gradually decreasing in a direction away from the backlight light source. The diffusion layer refers to a resin layer containing diffusion particles.

In some embodiments, as shown in fig. 10, the optical plate includes two diffusion layers, and assuming that the horizontal lengths of the partitions of the backlight light source are both L, the thickness of the optical plate is d; the refractive index of the matrix of the diffusion layer closest to the backlight light source is n₁The refractive index of the matrix of the diffusion layer furthest from the backlight source is n₂And n is₁>n₂，

1＜n₁/n₂Less than 2, L is more than or equal to d. Therefore, the light is effectively limited in a small subarea range after passing through the optical plate, and the condition that the light incident on one side edge of one backlight light source subarea just can be emergent on the other side edge of the optical plate can be met. The effects of uniform overall light emission and local light collection are realized.

In some embodiments, 1 < n₁/n₂Is less than 1.5. Thereby ensuring that the transmittance and diffusion effect of the optical sheet are within the preferred ranges.

In some casesIn the embodiment, in the method for preparing the composite material,

in order to achieve the above-mentioned effects of the optical plate, those skilled in the art can design the optical plate by combining optical simulation software.

According to a second aspect of the present disclosure, there is provided a display device, comprising a plurality of backlight light sources controlled in partitions, a display layer including a plurality of pixels, and an optical plate of any one of the above, wherein an area of one partition of the backlight light source is larger than an area of any one of the optical regions; when the display device is operated, light of the backlight light source reaches the display layer through the optical plate, and the pattern is displayed through the display layer. Fig. 3 is a schematic structural diagram of the display device, and as can be seen by comparing the display effects of fig. 3 and fig. 2, the image display region set by Z2 is a white region, the region other than the region Z2 is a non-display region, and if Z1 is not pure black, it represents light leakage, and the black color of the Z1 light leakage region in fig. 3 is darker than the black color of the Z1 light leakage region in fig. 2, which means that light leakage is reduced, that is, the degree of blurring of the displayed image edge region is reduced, and the contrast is improved.

In some embodiments, the thickness of each reflector is less than or equal to 1 pixel, preferably less than or equal to 0.5 pixel, and more preferably less than or equal to 0.1 pixel. The dot pitch of the pixel points can be calculated according to the overall display size and resolution of the display device. The presence of the reflective member reduces the light extraction and impedes the light extraction from individual pixels, and therefore it is preferred that the thickness does not interfere with the visual perception of the pixel light.

In some embodiments, the orthographic projection of each of the optical regions is rectangular, and the lateral length of the partition of each backlight light source is greater than the lateral length of each optical region.

In some embodiments, the orthographic projection of each reflector does not cover the parting line of the partitions of each backlight light source. So that the reflector of the optical plate divides the light from the backlight light source more to form more secondary backlight partitions.

In some embodiments, the display device is a direct-type display device, and the optical plate is a diffusion plate; or the display device is a side-in type display device, and the optical plate is a light guide plate.

In some embodiments, the forward projection areas of the segments of the respective backlight light sources are not identical.

Hereinafter, embodiments will be described in more detail with reference to specific examples. However, they are illustrative examples of the present disclosure, and the present disclosure is not limited thereto.

Example 1

Direct type display device

Through optical software simulation: the display area is selected to be 100mm by 160 mm. The display image is set to have a hollow pattern as shown in fig. 11, and the visible light transmittance (or the light leakage ratio) of the display layer is set to 10%.

As shown in fig. 12, the backlight light source of 100mm × 160mm is divided into 9 backlight partitions of 24.9mm × 39.9mm rectangles and 16 rectangular backlight partitions of the remaining sizes. For the convenience of simulation, the partition interval is set to be 0.2mm (the width of the line of the dividing line is determined on software).

The diffuser plate with the size of 100mm multiplied by 160mm is divided into a plurality of rectangles with the size of 8.3mm multiplied by 13.3mm, the thickness of the reflector is 0.2mm (the width of the line is measured in software), the visible light transmittance of the diffuser plate is 50%, and the haze is 98%.

The simulation results are shown in FIG. 13. The horizontal and vertical coordinates are in mm, the same applies below.

Comparative example 1

Direct type display device

The other properties of the diffuser plate were the same as those of example 1, except that the diffuser plate and the backlight light source were not partitioned. The simulation results are shown in FIG. 14.

Comparative example 2

Direct type display device

The backlight partition situation is the same as in embodiment 1.

The other properties of the diffuser plate were the same as in example 1, except that the diffuser plate had no partitions. The simulation results are shown in FIG. 15.

It should be noted that, because the resolution of the software and the display is limited, the applicant can increase the brightness of the picture of the simulation result by 10% at the same time to obtain fig. 13 to 15, which is convenient for viewing the difference of the simulation result. From the simulation results, the simulation results of example 1 have no obvious gray scale at the edge, the simulation results of comparative example 2 have a certain gray scale at the edge, and the simulation results of comparative example 1 have a obvious gray scale at the edge. The above results confirm that example 1 has the effect of improving contrast.

The above description is only a preferred embodiment of the present disclosure and is not intended to limit the present disclosure, and various modifications and changes may be made to the present disclosure by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present disclosure should be included in the protection scope of the present disclosure.

Claims

1. The optical plate is characterized in that a plurality of reflectors perpendicular to the bottom surface of the optical plate are arranged in the optical plate, the reflectors are regularly arrayed, the reflectors separate the optical plate to form a plurality of optical areas, and the optical plate is used for optically connecting a plurality of backlight sources controlled in a subarea mode.

2. The optical panel of claim 1, wherein each of said reflecting members has a thickness of 0.5mm or less, preferably 0.25mm or less.

3. The optical panel of claim 1, wherein each of said reflecting members has a reflectivity of not less than 50%, preferably not less than 80%.

4. The optical panel of claim 1, wherein the orthographic projection of each of said optical zones is rectangular, and the lateral length of each of said optical zones is one or more; when there are a plurality of lateral lengths of the respective optical regions, the optical regions of the same lateral length are not adjacent to each other.

5. The optical panel of claim 1, wherein the orthographic projection of each of the optical regions has the same shape, preferably the same area.

6. The optical plate of claim 1, wherein the main body of the optical plate is a resin material, the optical plate further comprising a quantum dot material, the quantum dot material being dispersed in the resin material.

7. The optical panel of claim 1, wherein the reflectivity of the reflecting member is gradually reduced in a direction away from the backlight light source.

8. The optical sheet of claim 1, wherein the optical sheet comprises a matrix of a resin material, the matrix having a refractive index gradually decreasing in a direction away from the backlight light source.

9. The optical sheet of claim 1, wherein the optical sheet comprises a matrix of a resin material and diffusion particles dispersed in the matrix, the concentration of the diffusion particles being gradually reduced in a direction away from the backlight light source.

10. The optical sheet of claim 1, wherein the optical sheet comprises a plurality of diffusion layers stacked, and the refractive index of the matrix of each of the diffusion layers is gradually decreased in a direction away from the backlight light source.

11. The optical plate of claim 10, wherein the optical plate comprises two diffusion layers, and assuming that the partitions of the backlight light source have a transverse length of L, the thickness of the optical plate is d; the refractive index of the matrix of the diffusion layer closest to the backlight light source is n₁The refractive index of the matrix of the diffusion layer furthest from the backlight light source is n₂And n is₁>n₂，

12. The optical panel of claim 11,

13. a display device, comprising a plurality of backlight sources controlled in zones and a display layer having a plurality of pixels, further comprising the optical sheet of any one of claims 1 to 12, wherein the orthographic projection area of a zone of the backlight source is larger than the orthographic projection area of any one of the optical zones; when the display device works, the light of the backlight light source reaches the display layer through the optical plate, and the pattern is displayed through the display layer.

14. The display device according to claim 13, wherein the thickness of each of the reflective members is equal to or less than 1 pixel, preferably equal to or less than 0.5 pixel, and more preferably equal to or less than 0.1 pixel.

15. The display device according to claim 13, wherein the orthographic projection of each of the optical regions is rectangular, and the lateral length of the sub-region of each of the backlight light sources is greater than the lateral length of each of the optical regions.

16. The display device according to claim 13, wherein the orthographic projection of each of the reflecting members does not cover the division line of the partitions of each of the backlight light sources.

17. The display device according to claim 13, wherein the display device is a direct-type display device, and the optical plate is a diffusion plate; or the display device is a lateral display device, and the optical plate is a light guide plate.