CN110750009A

CN110750009A - Display device

Info

Publication number: CN110750009A
Application number: CN201911063235.4A
Authority: CN
Inventors: 周婷; 沈柏平; 李俊谊
Original assignee: Xiamen Tianma Microelectronics Co Ltd
Current assignee: Xiamen Tianma Microelectronics Co Ltd
Priority date: 2019-10-31
Filing date: 2019-10-31
Publication date: 2020-02-04

Abstract

The invention discloses a display device, which belongs to the technical field of display and comprises a direct type backlight module, a first display panel and a second display panel, wherein the first display panel and the second display panel are oppositely arranged; the direct type backlight module at least comprises a substrate base plate, wherein the surface of one side, close to the first display panel, of the substrate base plate is provided with a plurality of mini LED lamp beads which are arranged in an array manner; the first liquid crystal layer of the first display panel includes polymer dispersed liquid crystal. The invention can realize pixel-level light intensity control, realize high-precision local adjustment of display brightness, avoid the phenomena of bluing, starry sky and the like at the edge of the second display panel in the display process, improve the uniformity of the display brightness, simultaneously achieve the vision of human eyes with brightness and chromaticity closer to reality, and improve the display quality of the display device.

Description

Display device

Technical Field

The invention relates to the technical field of display, in particular to a display device.

Background

With the development of liquid crystal display technology, liquid crystal display modules have been widely used in liquid crystal display devices such as mobile phones and tablet computers. However, since the lcd panel of the lcd device does not have the function of emitting light, a backlight module is required to be disposed below the lcd panel to provide the required light source, so as to achieve the display effect.

From the trend of technology development, how to reduce the power consumption of the backlight is most concerned. Because the backlight source is the largest energy consumer, the power consumption of the backlight is reduced, and the power consumption of the whole machine is also greatly reduced. The technology includes improving the driving circuit of the backlight source, improving the luminous efficiency of the LED (Light-Emitting Diode), developing new LED types, currently, Local Dimming (Local backlight adjustment) uses a backlight composed of hundreds of LEDs to replace a cold cathode backlight, the backlight LED can be adjusted according to the brightness of the image, the brightness of the highlight part in the display screen image can be maximized, and the brightness of the dark part can be reduced or even turned off to achieve the best contrast. Thus, the reduction in the brightness of the dark area reduces the power consumption of the backlight. Especially, the direct type LED backlight is matched with the Local Dimming technology, so that the electric quantity can be greatly reduced, the contrast value and the gray scale number of a display picture can be improved, the residual shadow can be reduced, and the like. As one of the functions of improving the display image quality, it is possible to increase the video playback appeal of a display device by using an HDR (High Dynamic Range) technique. Because the HDR technology has strict requirements on the display screen in terms of contrast, brightness, color saturation, Bit depth and resolution, the existing HDR technology is matched with Local Dimming surface backlight to control the regional brightness, so that the brightness and the chromaticity are closer to real human vision, but the edge of the display device in the prior art generates the phenomena of bluing, starry sky and the like in the display process, and the display brightness of the display device is not uniform.

Therefore, it is an urgent technical problem to be solved by those skilled in the art to provide a display device capable of realizing pixel-level light intensity control, realizing high-precision local adjustment of display brightness, and solving the problem of non-uniform display brightness.

Disclosure of Invention

In view of the above, the present invention provides a display device to solve the problem of uneven display brightness of the display device due to the occurrence of phenomena such as bluing and starry sky at the edge of the display device in the prior art.

The present invention provides a display device including: the backlight module comprises a direct type backlight module, a first display panel and a second display panel, wherein the first display panel and the second display panel are arranged oppositely, the second display panel is positioned on one side of a light emergent surface of the first display panel, and the direct type backlight module is positioned on one side of the first display panel far away from the second display panel; the direct type backlight module at least comprises a substrate base plate, wherein the surface of one side, close to the first display panel, of the substrate base plate is provided with a plurality of mini LED lamp beads which are arranged in an array manner; the first display panel comprises a first substrate, a second substrate and a first liquid crystal layer, wherein the first substrate and the second substrate are oppositely arranged, the first liquid crystal layer is clamped between the first substrate and the second substrate, and the first liquid crystal layer comprises polymer dispersed liquid crystal; a first electrode is arranged on the surface of the first substrate facing the first liquid crystal layer, and a second electrode is arranged on the surface of the second substrate facing the first liquid crystal layer; the second display panel includes at least: the liquid crystal display panel comprises a lower polarizer, a third electrode, a second liquid crystal layer, a fourth electrode, a color film substrate and an upper polarizer; and a lower polarizer, a third electrode, a second liquid crystal layer, a fourth electrode, a color film substrate and an upper polarizer are sequentially arranged on one side of the second substrate far away from the first liquid crystal layer along the direction vertical to the light-emitting surface of the first display panel.

Compared with the prior art, the display device provided by the invention at least realizes the following beneficial effects:

the direct type backlight module is combined with the first display panel to be used as the backlight of the second display panel, the first display panel can perform local partition control on light rays emitted by the direct type backlight module, pixel-level light intensity control of a display picture of the first display panel is achieved by taking pixels of the first display panel as units, and high-precision brightness adjustment of the whole display device is achieved. The invention further uses the first display panel as a control valve for local backlight adjustment of the direct type backlight module, the adjustment unit for light transmission of the second display panel is not limited no matter the size of the partition of the direct type backlight module, and even the pixel level light intensity control by taking the pixel of the first display panel as a unit can be achieved in a fine mode, so that the pixel level light intensity control can be achieved, the high-precision local adjustment of the display brightness can be achieved, the phenomena of bluing, starry sky and the like at the edge of the second display panel in the display process can be avoided, the uniformity of the display brightness can be improved, meanwhile, the brightness and the chromaticity can be closer to the real human vision, and the display quality of the display device can be improved.

Of course, it is not necessary for any product in which the present invention is practiced to specifically achieve all of the above-described technical effects simultaneously.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

Fig. 1 is a schematic plan view of a display device according to an embodiment of the present invention;

FIG. 2 is a schematic sectional view taken along line A-A' of FIG. 1;

FIG. 3 is a schematic cross-sectional view taken along line B-B' of FIG. 1;

FIG. 4 is a schematic view of another cross-sectional structure taken along line B-B' of FIG. 1;

FIG. 5 is a schematic view of another cross-sectional structure taken along line B-B' of FIG. 1;

FIG. 6 is a schematic view of another cross-sectional structure taken along line A-A' of FIG. 1;

FIG. 7 is a schematic view of another cross-sectional structure taken along line B-B' of FIG. 1;

fig. 8 is a schematic plan view of another display device according to an embodiment of the present invention;

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

Referring to fig. 1 and fig. 2, fig. 1 is a schematic plan view of a display device according to an embodiment of the present invention, fig. 2 is a schematic cross-sectional view taken along a direction a-a' in fig. 1, and a display device 000 according to the present embodiment includes: the backlight module comprises a direct type backlight module 30, a first display panel 10 and a second display panel 20, wherein the first display panel 10 and the second display panel 20 are oppositely arranged, the second display panel 20 is positioned on one side of a light emergent surface E of the first display panel 10, and the direct type backlight module 30 is positioned on one side of the first display panel 10 far away from the second display panel 20;

the direct type backlight module 30 at least comprises a substrate base plate 301, wherein a plurality of mini LED lamp beads 302 arranged in an array are arranged on the surface of the substrate base plate 301 close to one side of the first display panel 10;

the first display panel 10 includes a first substrate 101 and a second substrate 102 disposed opposite to each other, and a first liquid crystal layer 103 interposed between the first substrate 101 and the second substrate 102, the first liquid crystal layer 103 including polymer dispersed liquid crystal; a first electrode 104 is arranged on the surface of the first substrate 101 facing the first liquid crystal layer 103, and a second electrode 105 is arranged on the surface of the second substrate 102 facing the first liquid crystal layer 103;

the second display panel 20 includes at least: a lower polarizer 201, a third electrode 202, a second liquid crystal layer 203, a fourth electrode 204, a color film substrate 205, and an upper polarizer 206;

along a direction Y perpendicular to the light emitting surface E of the first display panel 10, a lower polarizer 201, a third electrode 202, a second liquid crystal layer 203, a fourth electrode 204, a color filter substrate 205, and an upper polarizer 206 are sequentially disposed on a side of the second substrate 102 away from the first liquid crystal layer 103.

Specifically, the display device 000 of the embodiment includes a direct-type backlight module 30, a first display panel 10, and a second display panel 20 stacked in sequence, wherein the first display panel 10 is located between the direct-type backlight module 30 and the second display panel 20, the second display panel 20 is located on a side of an emergent surface E of the first display panel 10, that is, the first display panel 10 includes an incident surface F and an emergent surface E, the direct-type backlight module 30 is located on the side of the incident surface F of the first display panel 10, and the second display panel 20 is located on the side of the emergent surface E of the first display panel 10. The direct-type backlight module 30 is used for providing a direct-type surface light source, and the first display panel 10 is used for locally controlling light emitted from the direct-type backlight module 30, so as to realize pixel-level light intensity control of a display image of the second display panel 20, and thus the whole display device 000 can perform high-precision brightness adjustment.

Wherein, straight following formula backlight unit 30 includes substrate base plate 301 at least, substrate base plate 301 is close to the mini LED lamp pearl 302 that first display panel 10 one side was equipped with a plurality ofly to be array arrangement (not illustrated in the figure) on the surface, mini LED lamp pearl 302 is once again famous time millimeter emitting diode, indicate the LED of crystalline grain size about more than 100 microns, in the technological principle, straight following formula backlight unit 30 that adopts the mini LED lamp pearl 302 of a plurality of array arrangements to make dynamic partition is many, the response speed of adjusting luminance is faster, control accuracy is higher, can promote the speed and each partition luminance of dynamic partition backlight response by a wide margin, can also cut down backlight unit's thickness.

The first display panel 10 includes a first substrate 101 and a second substrate 102 disposed opposite to each other, and a first liquid crystal layer 103 interposed between the first substrate 101 and the second substrate 102, the first liquid crystal layer 103 including polymer dispersed liquid crystal; the surface of the first substrate 101 facing the first liquid crystal layer 103 is provided with a first electrode 104, the surface of the second substrate 102 facing the first liquid crystal layer 103 is provided with a second electrode 105, the first display panel 10 does not need to be provided with a polarizer, and different gray scale pictures can be displayed, the first display panel 10 does not include a polarizer and color resistance, and compared with the prior art, the transmittance of the first display panel 10 can be improved. The first liquid Crystal layer 103 of the first display panel 10 includes Polymer Dispersed Liquid Crystal (PDLC) in which liquid Crystal is dispersed in an organic solid Polymer matrix in small droplets of the order of micrometers. Because the optical axis of the small droplets formed by the liquid crystal molecules is in free orientation, the refractive index of the small droplets is not matched with that of the substrate, and when the light rays emitted by the direct type backlight module 30 pass through the substrate, the light rays are strongly scattered by the droplets and are in an opaque milky white state or a semitransparent state. Voltages are applied to the first electrode 104 and the second electrode 105 below and above the first liquid crystal layer 103, respectively, and an electric field formed between the first electrode 104 and the second electrode 105 can adjust the optical axis orientation of liquid crystal droplets, and when the refractive indices of the two are matched, the first display panel 10 assumes a transparent state. The electric field is removed and the liquid crystal droplets restore the original state of astigmatism, thereby performing the display. Therefore, the first display panel 10 does not need to be provided with a polarizer, and the display with different transparencies can be realized only by adjusting the electric field between the first electrode 104 and the second electrode 105, so as to adjust the transmittance of light, thereby enabling the first display panel 10 to display different gray-scale pictures. In this embodiment, the first electrode 104 may be one of a pixel electrode and a common electrode, and the second electrode 105 is the other, and voltages are applied to the pixel electrode and the common electrode, respectively, so that an electric field is formed between the pixel electrode and the common electrode, and the electric field controls liquid crystal molecules of polymer dispersed liquid crystal in the first liquid crystal layer 103 to deflect, thereby realizing display with different transparencies.

The second display panel 20 is a liquid crystal display panel, and a lower polarizer 201, a third electrode 202, a second liquid crystal layer 203, a fourth electrode 204, a color film substrate 205, and an upper polarizer 206 are sequentially disposed on one side of the second substrate 102 away from the first liquid crystal layer 103 along a direction Y perpendicular to the light emitting surface E of the first display panel 10. The second display panel 20 operates on the principle that driving voltages are applied to the fourth electrode 204 on the color filter substrate 205 and the third electrode 202 on the second substrate 102, respectively, so that an electric field is formed between the fourth electrode 204 and the third electrode 202 to control the rotation of liquid crystal molecules in the second liquid crystal layer 203, change the polarization state of the light emitted from the light emitting surface E of the first display panel 10, and realize the penetration and blocking of the light path by the upper polarizer 206 and the lower polarizer 201 of the second display panel 20 to control the amount of light transmission, so as to refract the light emitted from the light emitting surface E of the first display panel 10 to generate a picture. The second display panel 20 and the first display panel 10 of the present embodiment share the second substrate 102 as an array substrate, which is beneficial to the thinning of the display device 000. The lower polarizer 201 is located on the side of the second substrate 102 away from the first liquid crystal layer 103, i.e. the lower polarizer 201 of the second display panel 20 is designed as a built-in structure, so that the lower polarizer 201 can be directly plated on the second substrate 102 in the manufacturing process, which can save the cost of the traditional external polarizer, and the thickness of the upper polarizer 206 and the lower polarizer 201 is generally less than 100 microns, and the thickness is thinner, so that when the lower polarizer 201 is disposed on the side surface of the second substrate 102 close to the second liquid crystal layer 203, the operating voltage of the second display panel 20 will not be adversely affected. A polarizer is an optical filter that can filter a light beam having multiple polarization directions into a light beam having a single polarization direction. In the second display panel 20, the light emitted from the light emitting surface E of the first display panel 10 passes through the lower polarizer 201 and becomes linearly polarized light, the polarization characteristics of the liquid crystal in the second liquid crystal layer 203 are changed, and the linearly polarized light passes through the upper polarizer 206 and exits from the second display panel 20, so that the effect of adjusting the brightness of the exiting light is achieved by adjusting the orientation of the liquid crystal in the second liquid crystal layer 203.

In this embodiment, the direct-type backlight module 30 is combined with the first display panel 10, so that the direct-type backlight module is used as the backlight of the second display panel 20, the first display panel 10 can perform local partition control on light emitted from the direct-type backlight module 30, and the pixel-level light intensity control of the display image of the first display panel 10 is realized by using the pixels of the first display panel 10 as units, so as to realize high-precision brightness adjustment of the whole display device 000. In the prior art, in the liquid crystal display device using the direct type backlight module 30 using the mini LED as the light source as the backlight, the division for controlling the area brightness is too large, which may cause the power consumption of the mini LED to increase, so the present embodiment further uses the first display panel 10 as the control valve for adjusting the local backlight of the direct type backlight module 30, no matter the size of the division of the direct type backlight module 30, the adjustment unit for the light of the second display panel 20 to penetrate is not limited, and even the pixel level light intensity control using the pixel of the first display panel 10 as the unit can be refined, so as to realize the pixel level light intensity control, and realize the high-precision local adjustment of the display brightness, and avoid the phenomena of bluing, starry sky, etc. at the edge of the second display panel 20 during the display process, while improving the uniformity of the display brightness, the brightness and the chromaticity can be closer to the real human vision, the display quality of the display device 000 is improved.

It should be noted that the first substrate 101 of the present embodiment may be flexible or hard; the second substrate 102 may be flexible or rigid. The first substrate 101 and the second substrate 102 may be made of a material with high transparency, so as to further improve the transmittance of the display device 000. In this embodiment, the light incident surface F of the first display panel 10 means that light emitted from the direct-type backlight module 30 enters the first display panel 10 through the light incident surface F; the light emitting surface E of the first display panel 10 is a surface from which light emitted from the direct-type backlight module 30 passes through the first display panel 10 and then is emitted to the second display panel 20, so as to provide backlight with different pixel intensities for the second display panel 20.

It should be further noted that fig. 1 and fig. 2 of the present embodiment only schematically illustrate the structure of the display device 000 related to the technical solution of the present embodiment, and it is understood that the display device 000 of the present embodiment may further include other existing structures capable of implementing a display function, such as a frame adhesive, an optical adhesive, and the like, and a color resist layer and a black matrix of the second display panel 20, which are not described herein again. In the embodiment of the present invention, a gap exists between the first display panel 10 and the direct-type backlight module 30 in fig. 2, but in an actual production process, the first display panel 10 and the direct-type backlight module 30 are fixedly connected and do not have the gap or the gap is very small and negligible, for example, the first display panel 10 and the direct-type backlight module 30 may be combined and fixed by using a frame glue or a transparent oca (optical Clear adhesive) optical glue or other bonding methods having the same fixing effect, or may be other fixing methods.

In some optional embodiments, please refer to fig. 1, fig. 3 and fig. 4, fig. 3 is a schematic cross-sectional view along the direction B-B 'in fig. 1, fig. 4 is a schematic cross-sectional view along the direction B-B' in fig. 1, in this embodiment, the display device 000 further includes a first driving unit 40 and a second driving unit 50, the first driving unit 40 is electrically connected to the direct-type backlight module 30 and the first display panel 10, respectively, and the second driving unit 50 is electrically connected to the second display panel 20.

The embodiment further explains that the display device 000 further includes a first driving unit 40 and a second driving unit 50, and the first driving unit 40 and the second driving unit 50 may be disposed in a non-display area of the display device 000, and thus may not occupy the range of the display area. Alternatively, the first and

second driving units

40 and 50 may be any one of a driving chip or a flexible circuit board. The first driving unit 40 is electrically connected to the first display panel 10, and the first driving unit 40 is configured to provide a display driving signal for the first display panel 10, so that an electric field is formed between the first electrode 104 and the second electrode 105 in the first display panel 10, and the electric field controls liquid crystal molecules of polymer dispersed liquid crystal in the first liquid crystal layer 103 to deflect, thereby implementing display with different transparencies. The second driving unit 50 is electrically connected to the second display panel 20, the second driving unit 50 is configured to provide a display driving signal for the second display panel 20, the second driving unit 50 provides the display driving signal, a driving voltage is applied to the fourth electrode 204 on the color filter substrate 205 and the third electrode 202 on the second substrate 102, respectively, an electric field is formed between the fourth electrode 204 and the third electrode 202 to control rotation of liquid crystal molecules in the second liquid crystal layer 203, a polarization state of the light exiting from the light exit surface E of the first display panel 10 is changed, a light path is penetrated and blocked by the upper polarizer 206 and the lower polarizer 201 of the second display panel 20 to control a light transmission amount, and finally the light exiting from the light exit surface E of the first display panel 10 is refracted to generate a display image of the second display panel 20. First drive unit 40 still is connected with straight following formula backlight unit 30 electricity, the straight following formula backlight unit 30's that adopts the mini LED lamp pearl 302 of a plurality of array arrangements first drive unit 40 of sharing is driven with first display panel 10, first drive unit 40 can be connected to on each mini LED lamp pearl 302 through the wire, long-range unified control, or can also make independent backlight drive circuit of each mini LED lamp pearl 302 electricity connection, this backlight drive circuit can integrate in first drive unit 40, it is faster to realize the response speed of adjusting luminance, control accuracy is higher, promote the speed of dynamic subregion response in a poor light and the luminance of each subregion by a wide margin, be favorable to reducing backlight unit's thickness.

It should be noted that, in this embodiment, only the first driving unit 40 is electrically connected to the direct-type backlight module 30 and the first display panel 10, and the second driving unit 50 is electrically connected to the second display panel 20, and the positions where the first driving unit 40 and the second driving unit 50 are disposed are not particularly limited, for example, the first driving unit 40 and the second driving unit 50 may be disposed on the second substrate 102 and located on the same side of the second substrate 102 (as shown in fig. 3 and 4), and at this time, the first driving unit 40 and the second driving unit 50 may be disposed on a side of the second substrate 102 away from the first liquid crystal layer 103 (as shown in fig. 3), or the first driving unit 40 and the second driving unit 50 may be disposed on a side of the second substrate 102 close to the first liquid crystal layer 103 (as shown in fig. 4), and the second substrate 102 may be a flexible substrate, so that the portion of the second substrate 102 where the first driving unit 40 and the second driving unit 50 are disposed may face the first liquid crystal layer The direction of the light source 103 (the direction of the arrow G in fig. 3 and 4) is bent, and the driving function is realized, which is advantageous for narrowing the frame of the display device 000. The present embodiment does not specifically limit the positions where the first driving unit 40 and the second driving unit 50 are disposed, and only needs to provide a driving signal of the display device through the electrical connection.

In some alternative embodiments, referring to fig. 1 and fig. 5, fig. 5 is another cross-sectional structure schematic diagram of a direction B-B' in fig. 1, in the present embodiment, in a direction Y perpendicular to the light emitting surface E of the first display panel 10, the first driving unit 40 is located on a side of the second substrate 102 close to the first liquid crystal layer 103, and the second driving unit 50 is located on a side of the second substrate 102 away from the first liquid crystal layer 103.

The present embodiment further explains that the first driving unit 40 and the second driving unit 50 may be disposed on the second substrate 102, and the first driving unit 40 and the second driving unit 50 are disposed on different sides of the second substrate 102 (as shown in fig. 5), that is, in a direction Y perpendicular to the light emitting surface E of the first display panel 10, the first driving unit 40 is disposed on one side of the second substrate 102 close to the first liquid crystal layer 103, and the second driving unit 50 is disposed on one side of the second substrate 102 far from the first liquid crystal layer 103, so as to reduce the area of the non-display area occupied by the two driving units on the same side of the second substrate 102, and to facilitate the realization of a narrow frame of the display device 000. The first driving unit 40 is located on one side of the second substrate 102 close to the first liquid crystal layer 103, and the second driving unit 50 is located on one side of the second substrate 102 close to the second liquid crystal layer 203, so that the first driving unit 40 is more conveniently and electrically connected with the first display panel 10 and the direct-type backlight module 30 on the same side, and the second driving unit 50 is more conveniently and electrically connected with the second display panel 20 on the same side, which is beneficial to reducing the difficulty of process wiring.

In some alternative embodiments, referring to fig. 1 and fig. 6, fig. 6 is a schematic cross-sectional view along the direction a-a' in fig. 1, in which the second display panel 20 further includes an array substrate 60, and the array substrate 60 is located between the lower polarizer 201 and the second liquid crystal layer 203.

This embodiment further explains that the second display panel 20 of the display device 000 may further include an array substrate 60 located between the lower polarizer 201 and the second liquid crystal layer 203, that is, in a direction away from the first display panel 10, the second display panel 20 sequentially includes the lower polarizer 201, the array substrate 60, the third electrode 202, the second liquid crystal layer 203, the fourth electrode 204, the color filter substrate 205, and the upper polarizer 206, that is, the second substrate 102 of the first display panel 10 is not shared with the second display panel 20, the second display panel 20 is provided with an independent array substrate 60 for laying the circuit structures of the pixel units on a side of the array substrate 60 close to the second liquid crystal layer 203, and the circuit structures of the pixel units of the first display panel 10 may be disposed on a side of the second substrate 102 facing the first liquid crystal layer 103 or disposed on a side of the first substrate 101 facing the first liquid crystal layer 103, the process difficulty of arranging the circuits on two sides of the same substrate is reduced, and the accuracy of attaching the first display panel 10 and the second display panel 20 by attaching the array substrate 60 and the second substrate 102 is improved.

In some alternative embodiments, referring to fig. 1 and fig. 7, fig. 7 is a schematic cross-sectional view taken along the direction B-B' in fig. 1, in which in the present embodiment, the first driving unit 40 is located on a side of the second substrate 102 away from the lower polarizer 201, and the second driving unit 50 is located on a side of the array substrate 60 away from the lower polarizer 201.

The present embodiment further explains that the first driving unit 40 is independently disposed on a side of the second substrate 102 away from the lower polarizer 201, and the second driving unit 50 is independently disposed on a side of the array substrate 60 away from the lower polarizer 201, that is, in a direction Y perpendicular to the light emitting surface E of the first display panel 10, the first driving unit 40 and the second driving unit 50 are respectively located on different substrates (as shown in fig. 7), so that the process difficulty of fabricating two driving units on the same substrate is reduced, the area of a non-display area occupied by the two driving units on the same substrate is also reduced, and the narrow frame of the display device 000 is also facilitated. The first driving unit 40 is located on a side of the second substrate 102 away from the lower polarizer 201, and the second driving unit 50 is located on a side of the array substrate 60 away from the lower polarizer 201, so that the first driving unit 40 is more conveniently and electrically connected to the first display panel 10 and the direct-type backlight module 30 on the same side, and the second driving unit 50 is more conveniently and electrically connected to the second display panel 20 on the same side, which is beneficial to reducing the difficulty of manufacturing process wiring.

In some alternative embodiments, referring to fig. 8, fig. 8 is a schematic plan view illustrating another display device according to an embodiment of the present invention, in which a display device 000 in the embodiment includes a plurality of light emitting regions LA arranged in an array, a first display panel 10 includes a plurality of first pixels P1 arranged in an array, and a second display panel 20 includes a plurality of second pixels P2 arranged in an array;

in one light emitting region LA, the number of the first pixels P1 is less than or equal to the number of the second pixels P2.

The present embodiment further explains that in the same light emitting region LA, the number of the first Pixels P1 included in the first display panel 10 is less than or equal to the number of the second Pixels P2 included in the second display panel 20, that is, the PPI (pixel density, which represents the number of Pixels Per Inch of the display panel) of the first display panel 10 is less than or equal to the PPI of the second display panel 20, and the higher the PPI value, that is, the higher the density of the display panel can display images, the higher the display density is, the higher the simulation degree is. Therefore, the present embodiment sets the PPI of the second display panel 20 for displaying pictures to be greater than or equal to the PPI of the first display panel 10 used as a backlight, so that the density and the fidelity of the pictures displayed by the second display panel 20 can be improved, which is beneficial to improving the display quality.

In some optional embodiments, with reference to fig. 8, in the present embodiment, in one light emitting region LA, the first display panel 10 includes M first pixels P1, and the second display panel 20 includes N second pixels P2, where N ═ k × M, and k is a positive integer. In order to clearly illustrate the number relationship between the first pixels P1 of the first display panel 10 and the second pixels P2 of the second display panel 20 in the same light-emitting area LA, fig. 7 of the present embodiment illustrates an example in which the first display panel 10 includes 2 first pixels P1 and the second display panel 20 includes 8 second pixels P2 in one light-emitting area LA.

The present embodiment further explains that, in the same light-emitting region LA, the number N of the second pixels P2 included in the second display panel 20 is an integral multiple of the number M of the first pixels P1 included in the first display panel 10, so that the boundary of each first pixel P1 of the first display panel 10 used as a backlight can be exactly between two adjacent second pixels P2 of the second display panel 20, and the display effect of the second display panel 20 can be prevented from being affected by the boundary of each first pixel P1 of the first display panel 10 used as a backlight being at the middle position of one of the second pixels P2 of the second display panel 20.

In some alternative embodiments, with continued reference to fig. 1-7, in the present embodiment, the second liquid crystal layer 203 includes high brightness negative liquid crystal.

The present embodiment further explains that the second liquid crystal layer 203 of the second display panel 20 for displaying pictures includes high brightness negative liquid crystal, and since high brightness and high contrast can be realized by the high brightness negative liquid crystal, setting the liquid crystal of the second liquid crystal layer 203 as the high brightness negative liquid crystal is advantageous for improving the overall brightness and contrast of the display device. Specifically, in general, positive liquid crystal molecules are arranged along the direction of the electric field under the action of an external electric field, while negative liquid crystal molecules are arranged perpendicular to the direction of the electric field, and since the negative liquid crystal molecules rotate along the direction perpendicular to the direction of the electric field, when an electric field for display is applied between the third electrode 202 and the fourth electrode 204 of the second display panel 20, the negative liquid crystal molecules of the second liquid crystal layer 203 rotate in a plane parallel to the array substrate 60 and the color filter substrate 205, and finally, the minor axis direction of the negative liquid crystal molecules is parallel to the direction of the electric field, so that the light transmittance of the second liquid crystal layer 203 is better, and the transmittance of the second display panel 20 thus manufactured is higher.

In some alternative embodiments, please continue to refer to fig. 7, in the embodiment, in the direction Y perpendicular to the light emitting surface E of the first display panel 10, the thickness D1 of the first display panel 10 is 9-13 μm, and the thickness D2 of the second display panel 20 is 2.5-3.5 μm.

This embodiment further explains that since the first liquid crystal layer 103 is a polymer dispersed liquid crystal and the second liquid crystal layer 203 is a high brightness negative liquid crystal, the liquid crystal materials are selected such that the thickness D1 of the first display panel 10 is in the range of 9-13 μm and the thickness D2 of the second display panel 20 is in the range of 2.5-3.5 μm.

As can be seen from the above embodiments, the display device provided by the present invention at least achieves the following beneficial effects:

Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.

Claims

1. A display device, comprising: the backlight module comprises a direct type backlight module, a first display panel and a second display panel, wherein the first display panel and the second display panel are arranged oppositely, the second display panel is positioned on one side of a light emergent surface of the first display panel, and the direct type backlight module is positioned on one side of the first display panel, which is far away from the second display panel;

the direct type backlight module at least comprises a substrate base plate, wherein a plurality of miniLED lamp beads arranged in an array manner are arranged on the surface of one side, close to the first display panel, of the substrate base plate;

the first display panel comprises a first substrate and a second substrate which are oppositely arranged, and a first liquid crystal layer which is clamped between the first substrate and the second substrate and comprises polymer dispersed liquid crystal; a first electrode is arranged on the surface of the first substrate facing the first liquid crystal layer, and a second electrode is arranged on the surface of the second substrate facing the first liquid crystal layer;

the second display panel includes at least: the liquid crystal display panel comprises a lower polarizer, a third electrode, a second liquid crystal layer, a fourth electrode, a color film substrate and an upper polarizer;

the lower polarizer, the third electrode, the second liquid crystal layer, the fourth electrode, the color film substrate and the upper polarizer are sequentially arranged on one side of the second substrate, which is far away from the first liquid crystal layer, in a direction perpendicular to the light-emitting surface of the first display panel.

2. The display device according to claim 1, further comprising a first driving unit electrically connected to the direct-type backlight module and the first display panel, and a second driving unit electrically connected to the second display panel.

3. The display device according to claim 2, wherein the first driving unit is located on a side of the second substrate close to the first liquid crystal layer, and the second driving unit is located on a side of the second substrate away from the first liquid crystal layer, in a direction perpendicular to a light exit surface of the first display panel.

4. The display device according to claim 2, wherein the second display panel further comprises an array substrate between the lower polarizer and the second liquid crystal layer.

5. The display device according to claim 4, wherein the first driving unit is located on a side of the second substrate away from the lower polarizer, and the second driving unit is located on a side of the array substrate away from the lower polarizer.

6. The display device according to claim 1, wherein the display device comprises a plurality of light-emitting areas arranged in an array, the first display panel comprises a plurality of first pixels arranged in an array, and the second display panel comprises a plurality of second pixels arranged in an array;

in one of the light emitting regions, the number of the first pixels is smaller than or equal to the number of the second pixels.

7. The display device according to claim 6, wherein the first display panel includes M first pixels and the second display panel includes N second pixels in one of the light emitting regions, where N ═ kxm, and k is a positive integer.

8. The display device according to claim 1, wherein the second liquid crystal layer comprises a high brightness negative liquid crystal.

9. The display device according to claim 1, wherein the first display panel has a thickness of 9-13 μm in a direction perpendicular to the light exit surface of the first display panel.

10. The display device according to claim 1, wherein the second display panel has a thickness of 2.5-3.5 μm in a direction perpendicular to the light exit surface of the first display panel.