CN108153057B

CN108153057B - Quantum dot structure, backlight module and display device

Info

Publication number: CN108153057B
Application number: CN201810040117.0A
Authority: CN
Inventors: 许军; 张青
Original assignee: BOE Technology Group Co Ltd; Hefei BOE Optoelectronics Technology Co Ltd
Current assignee: BOE Technology Group Co Ltd; Hefei BOE Optoelectronics Technology Co Ltd
Priority date: 2018-01-16
Filing date: 2018-01-16
Publication date: 2020-08-21
Anticipated expiration: 2038-01-16
Also published as: CN108153057A

Abstract

The invention provides a quantum dot structure, a backlight module and a display device, belongs to the technical field of display, and can solve the problems that blue edges are easy to appear at the edge position of the existing quantum dot layer and the existing quantum dot layer is not suitable for narrow-view-angle products. In the quantum dot structure, the quantum dot material is arranged inside the plurality of bulges on one surface of the base material layer, so that when the whole layer of quantum dot structure is cut and applied, the quantum dot material is split along the outsides of the bulges, and the quantum dot material at the edge position after cutting is still positioned inside the bulges, is protected by the bulges, is not easy to be corroded and deteriorated by water and oxygen, and cannot influence the luminescence at the edge position. More importantly, when the projection is a paraboloid, the quantum dot structure can emit collimated light after being excited, and the collimation degree and the brightness are high. The quantum dot structure is suitable for various display devices, and is particularly suitable for narrow-viewing-angle products such as peep-proof products and ultra-narrow-viewing-angle products.

Description

Quantum dot structure, backlight module and display device

Technical Field

The invention belongs to the technical field of display, and particularly relates to a quantum dot structure, a backlight module and a display device.

Background

The display device generally includes a liquid crystal panel and a backlight module for providing backlight to the liquid crystal panel, wherein the backlight module is a side-in type backlight module including a blue light source, a light guide plate, a diffusion sheet and a plastic frame.

In the prior art, a quantum dot layer is usually disposed on one surface of a diffusion sheet in a side-entry backlight module, and the quantum dot layer is formed by doping a quantum dot material in a substrate layer. The quantum dot material in the quantum dot layer can emit monochromatic light after being irradiated by light with specific wavelength. Specifically, the light rays propagate in the side-in backlight module with the above structure in the following manner: the blue light emitted by the blue light source firstly enters from the light inlet surface of the light guide plate, then emits to the diffusion sheet from the light outlet surface of the light guide plate, and then the blue light emitted to the diffusion sheet passes through the quantum dot layer, at the moment, a part of the blue light excites the quantum dots to enable the quantum dots to emit red light or green light, and the other part of the blue light directly penetrates through the quantum dot layer and is mixed with the red light and the green light to form white light to be provided for the liquid crystal panel.

However, the inventors of the present application found that at least the following problems exist in the prior art: after the whole quantum dot layer is cut and applied, the doped quantum dot material at the edge position is easily corroded and deteriorated by water and oxygen, and the luminescence of the edge position is influenced. And because there is the gap between edge position and the frame of gluing to make the edge that partly blue light that the play plain noodles that makes from the light guide plate jetted out can pass through this gap, directly shine to liquid crystal display panel, and then make display device appear blue limit phenomenon, lead to display device's display effect not good. In addition, the backlight module of the existing quantum dot is mainly used for the display device with a large viewing angle, and is not suitable for narrow viewing angle products such as peep-proof products and ultra-narrow viewing angle products.

Disclosure of Invention

The invention provides a quantum dot structure, a backlight module and a display device, aiming at the problems that the edge position of the existing quantum dot layer is easy to generate blue edge and is not suitable for narrow-view-angle products.

The technical scheme adopted for solving the technical problem of the invention is as follows:

the utility model provides a quantum dot structure, includes the substrate layer of light-permeable, and locates a plurality of light-permeable archs on the substrate layer one side, protruding inside is equipped with the quantum dot material.

Optionally, the protrusions are arranged on the substrate layer in an array.

Optionally, each of the protrusions includes a plurality of quantum dot materials of different colors, and after the quantum dot materials in each of the protrusions are excited by non-visible light, the light emitted by the quantum dot materials is mixed into white light.

Optionally, the projection is a paraboloid, the paraboloid is a body obtained by rotating a parabola along a symmetry axis of the parabola, the quantum dot material is arranged at a focus of the parabola, and the quantum dot material can emit collimated light after being excited.

Optionally, a surface of the substrate layer provided with the protrusions is a first surface, a surface opposite to the first surface is a second surface, an orthographic projection from the parabolic body to the substrate layer is circular, a radius of the circular shape is z, a distance from a focus of the parabolic body to the second surface of the substrate layer is h, and a range of arctan (z/h) is 0-30 °.

Optionally, a plurality of retro-reflective structures are disposed at partial positions of the second surface of the substrate layer, and are used for retro-reflecting the non-collimated light of the second surface of the substrate layer.

Optionally, each parabolic body is correspondingly provided with a retro-reflective structure, the retro-reflective structure is annular, and the orthographic projection of the parabolic body to the substrate layer falls into the range encircled by the orthographic projection of the retro-reflective structure to the substrate layer.

Optionally, the thickness of the substrate layer is y, the focal length of the parabolic body is (1/2) P, the distance from the focal point of the parabolic body to the first surface of the substrate layer is r, and the annular width of the retroreflective structure in a direction parallel to the second surface is x, where x ═ y (P + r)/r.

The invention also provides a backlight module which comprises a backlight source and the quantum dot structure.

Optionally, the backlight source includes a light guide plate and a light source, the quantum dot structure is disposed on one side of the light exit surface of the light guide plate, and the protrusion is disposed closer to the light guide plate than the substrate layer.

Optionally, the light source may excite multiple color quantum dot materials.

Optionally, the side light source comprises an ultraviolet LED lamp.

The invention also provides a display device comprising the backlight module.

In the quantum dot structure, the quantum dot material is arranged inside the plurality of bulges on one surface of the substrate layer, so that when the whole layer of quantum dot structure is cut and applied, the quantum dot structure is cut along the outsides of the bulges, namely, the substrate layer is just cut off along the cutting position, the quantum dot material at the edge position after cutting is still positioned inside the bulges, namely, the environment of the quantum dot material before and after cutting is not changed, and the quantum dot structure is protected by the bulges, is not easy to be corroded and deteriorated by water and oxygen, and cannot influence the luminescence at the edge position. In addition, can also design bellied number and density on the substrate layer as required, design less arch in the border position department of waiting to cut, reserve the overlap joint of certain substrate layer and the tight silk dowel joint of gluey frame promptly in border position for seamless between substrate layer edge and the frame stops the gap light leak. More importantly, when the projection is a paraboloid, the quantum dot structure can emit collimated light after being excited, and the collimation degree and the brightness are high. The quantum dot structure is suitable for various display devices, and is particularly suitable for narrow-view-angle products such as peep-proof products and ultra-narrow-view-angle products, such as privacy display, 3D display, display of different pictures with different viewing angles, and the like.

Drawings

Fig. 1 is a schematic diagram of a quantum dot structure of embodiment 1 of the present invention;

fig. 2 is a schematic view of a quantum dot structure of embodiment 2 of the present invention;

fig. 3-5 are light extraction schematic diagrams of quantum dot structures according to embodiment 2 of the present invention;

fig. 6 and 9 are schematic diagrams of design dimensions and angles of a quantum dot structure according to embodiment 2 of the present invention;

fig. 7 is a schematic view of a quantum dot structure of embodiment 2 of the present invention;

fig. 8 is a schematic top view of a quantum dot structure of embodiment 2 of the present invention;

fig. 10 is a schematic structural view of a backlight module according to embodiment 3 of the invention;

fig. 11 is a schematic structural diagram of a display device according to embodiment 4 of the present invention;

wherein the reference numerals are: 1. a substrate layer; 2. a protrusion; 3. a quantum dot material; 4. a retroreflective structure; 5. a backlight source; 51. a light guide plate; 52. a side light source; 6. a display panel; 61. and (5) a color film.

Detailed Description

In order to make the technical solutions of the present invention better understood, the present invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

Example 1:

the present embodiment provides a quantum dot structure, as shown in fig. 1, including a substrate layer 1 that can transmit light, and a plurality of protrusions 2 that are arranged on one side of the substrate layer 1 and can transmit light, quantum dot material 3 is arranged inside the protrusions 2.

In the quantum dot structure of this embodiment, quantum dot material 3 sets up in a plurality of protruding 2's of substrate layer 1 one side inside, like this when the quantum dot structure of whole layer is cut the application, cut apart along protruding 2 outside, be equivalent to just make substrate layer 1 along cutting apart the position disconnection, quantum dot material 3 of border position department after the cutting still is in protruding 2 insidely, the environment that quantum dot material 3 locates does not change like this, it receives protruding 2 protection, it is difficult for being corroded rotten by water oxygen, can not influence the luminous of border position.

Example 2:

the present embodiment provides a quantum dot structure, as shown in fig. 2, including a light-permeable substrate layer 1, and a plurality of light-permeable protrusions 2 disposed on one surface of the substrate layer 1, where quantum dot materials 3 are disposed inside the protrusions 2; wherein, the bulges 2 are arranged on the substrate layer 1 in an array.

The figure 2 that this embodiment corresponds shows, and a plurality of archs 2 are arranged in one side array of

substrate layer

1, and 2 inside quantum dot materials 3 are evenly arranged for substrate layer 1 in the equivalent of arch, and the advantage that sets up like this is: the quantum dot material 3 can make the light emission more uniform when excited. Specifically, the bumps 2 are formed using a water-and-oxygen-repellent material (such as a resin) having a large refractive index, and the material forming the bumps 2 may be the same as or different from the material of the base layer 1, and the specific material is not limited herein. It should be noted that, can design 2 protruding number and density on the substrate layer 1 as required, design less protruding 2 in the border position department of waiting to cut, reserve the overlap joint of certain substrate layer 1 and the tight silk of gluey frame and close the seam promptly in border position for seamless between 1 edge of substrate layer and the frame stops the gap light leak.

As a preferred embodiment in this embodiment, each of the protrusions includes a plurality of quantum dot materials 3 with different colors, and after the quantum dot materials 3 in each protrusion are excited by non-visible light, the light emitted by them is mixed into white light.

In one embodiment, each of the protrusions 2 includes red, green, and blue quantum dot materials therein.

In this embodiment, each protrusion 2 includes a quantum dot material 3 with three primary colors, which is equivalent to mixing light after the quantum dot materials 3 with different colors of each protrusion 2 are excited, so that light emitted from each protrusion 2 through the substrate layer 1 is white light. The Quantum Dot (QD) material is a nanoparticle composed of II-VI or III-V elements, and can emit fluorescence after being excited, and the luminescence spectrum can be controlled by changing the size of the Quantum Dot. Specifically, the quantum dot material 3 includes CdS, CdSe, CdTe, ZnO, ZnS, ZnSe, ZnTe of II-VI groups, GaAs, GaP, GaAs, GaSb, HgS, HgSe, HgTe, InAs, InP, InSb, AlAs, AlP, AlSb and the like of III-V groups.

In one embodiment, as shown in fig. 3, the protrusion 2 is a paraboloid, the paraboloid is a body obtained by rotating a parabola along a symmetry axis of the parabola, the quantum dot material is arranged at a position of a focus of the parabola, and the quantum dot material can emit collimated light after being excited.

That is to say, the outer surface of the cross section of the protrusion 2 on the surface perpendicular to the substrate layer 1 is parabolic, and fig. 4 corresponding to this embodiment shows an enlarged structural cross section view of a single protrusion 2 and the substrate layer 1, where the shape of the protrusion 2 can be regarded as a parabolic shape, and the quantum dot material 3 is disposed at the focal position of the parabolic body, so that most of the excitation light is directly collimated and emitted as shown by a in fig. 5 after the quantum dot material 3 is excited, in this embodiment, the surface of the substrate layer where the protrusion is disposed is used as the first surface, and the surface opposite to the first surface is used as the second surface, where the second surface is the light emitting surface, that is, most of the light emitted at the position where the light emitting surface of the substrate layer 1 (the upper surface of the substrate layer 1 in fig. 4) faces the bottom surface of the parabolic body (the surface where the parabolic body contacts the substrate layer. Yet a small portion, shown as c in figure 5, is collimated after reflection off the surface of the projectile. When the quantum dot material 3 contains the quantum dot material 3 of three primary colors, light of the three primary colors can be mixed into white light at the light exit of the substrate layer 1. That is, the quantum dot structure of the present embodiment can emit collimated white light after being excited, and the quantum dot structure is suitable for narrow viewing angle products such as peep-proof products and ultra-narrow viewing angle products.

In one embodiment, the orthographic projection of the parabolic body to the substrate layer 1 is a circle, the radius of the circle is z, the distance from the focal point of the parabolic body to the light-emitting surface of the substrate layer 1 is h, and the range of arctan (z/h) is 0-30 °.

Fig. 6 corresponding to this embodiment shows a schematic diagram of a focal point, a distance h, and a radius z of a parabolic body, where tan θ is equal to z/h, and generally, when θ is smaller, the collimation degree of collimated light is higher, and arctan (z/h) ranges from 0 ° to 30 °, the collimation degree of collimated light is higher, and the light extraction rate is higher.

In one embodiment, a plurality of retro-reflective structures 4 are disposed at partial positions of the light exit surface of the substrate layer 1, and are used for retro-reflecting the non-collimated light of the light exit surface of the substrate layer 1.

It can be understood that not all emergent light of the light-emitting surface of the substrate layer 1 is collimated light, and a small amount of non-collimated light is inevitably emitted, and fig. 7 corresponding to this embodiment shows that the retro-reflective structure 4 is additionally arranged at a position of the non-collimated light, and the retro-reflective structure 4 functions as: as shown in b of fig. 5, the uncollimated light path is returned to the convex 2 structure, passes through the focus of the parabolic body and is collimated again.

As a preferred implementation in this embodiment, each parabolic body is correspondingly provided with a retro-reflective structure 4, the retro-reflective structure 4 is annular, and an orthographic projection of the parabolic body to the substrate layer 1 falls within a range enclosed by the orthographic projection of the retro-reflective structure 4 to the substrate layer 1.

The top view of the quantum dot structure is shown in the corresponding figure 8 of this embodiment, and on the light-emitting surface of substrate layer 1, a plurality of retro-reflective structures 4 are arranged in an array, wherein, the projectile body and retro-reflective structures 4 one-to-one, namely, a retro-reflective structure 4 is arranged at the position corresponding to each projectile body, thereby retro-reflecting the non-collimated light around each projectile body.

As a preferred implementation in this embodiment, as shown in fig. 9, the thickness of the substrate layer 1 is y, the focal length of the parabolic body is (1/2) P, the distance from the focal point of the parabolic body to the first surface of the substrate layer is r, and the ring width of the retroreflective structure 4 in the direction parallel to the light exit surface is x, where x is y (P + r)/r.

That is, referring to fig. 9, the inventors have creatively found that: when the thickness of substrate layer and the focus of projectile etc. satisfy x ═ y (P + r)/r relation, can make the product realize higher collimation degree, can also improve the luminance of product light-emitting, realize narrow visual angle. The brightness is obviously improved, and the narrow viewing angle is realized, so that the method has great significance for special applications such as privacy display, 3D display, display of different viewing angles and different pictures and the like.

It is to be understood that the sizes, thicknesses, etc. of the various structural layers shown in the drawings are merely illustrative. In the process implementation, the projection areas of the structural layers on the substrate may be the same or different, and the like, which are not listed here, and the required projection areas of the structural layers may be implemented by an etching process; meanwhile, the structure shown in the drawings is not limited to the geometric shape of each structural layer, and may be, for example, a rectangle shown in the drawings, a trapezoid, or other shapes formed by etching, and may also be realized by etching.

Example 3:

the embodiment provides a backlight module, which comprises a backlight source and the quantum dot structure.

The backlight module of the embodiment adopts the quantum dot structure, and the light emitted by the backlight module is collimated light, so that high-collimation emergent light can be realized. The backlight module does not need diffusion, prism sheets and the like, and is suitable for narrow-view-angle products such as peep-proof products and ultra-narrow-view-angle products.

As a preferred embodiment in this embodiment, as shown in fig. 10, the backlight 5 includes a light guide plate 51, and a side light source 52 disposed on one side of the light guide plate 51, the quantum dot structure is disposed on one side of the light exit surface of the light guide plate 51, and the protrusions 2 are disposed closer to the light guide plate 51 than the substrate layer 1.

In the embodiment, the side light source is taken as an example for description, and it is understood that the direct type backlight source is also feasible, and detailed description is omitted here.

As a preferred implementation in this embodiment, the side light sources 52 comprise ultraviolet LED lamps.

Compared with the white light obtained by exciting the red-green-blue quantum dot material 3 by using blue light and then mixing the red-green-blue quantum dot material 3 in the prior art, the scheme of the embodiment can further avoid the blue edge phenomenon because the blue light cannot penetrate through even a tiny gap exists at the position of the edge of the product. In the present embodiment, the ultraviolet LED lamp is taken as an example, and it is understood that any light source capable of exciting quantum dot materials of multiple colors is applicable.

Example 4:

the embodiment provides a display device, which comprises any one of the backlight modules. The display device may be: the display device comprises any product or component with a display function, such as a liquid crystal display panel, electronic paper, a mobile phone, a tablet personal computer, a television, a display, a notebook computer, a digital photo frame, a navigator and the like.

As a preferred implementation in this embodiment, as shown in fig. 11, the display device further includes a display panel 6 disposed on the light-emitting surface of the backlight module, wherein a color film 61 is disposed in the display panel 6, and the color film 61 cuts off the ultraviolet light in the backlight module, so as to better prevent the directly exposed ultraviolet light from being emitted for display.

It will be understood that the above embodiments are merely exemplary embodiments taken to illustrate the principles of the present invention, which is not limited thereto. It will be apparent to those skilled in the art that various modifications and improvements can be made without departing from the spirit and substance of the invention, and these modifications and improvements are also considered to be within the scope of the invention.

Claims

1. A quantum dot structure is characterized by comprising a light-permeable substrate layer and a plurality of light-permeable bulges arranged on one surface of the substrate layer, wherein quantum dot materials are arranged in the bulges; the parabolic mirror comprises a substrate layer, a parabolic mirror body, quantum dot materials, a base material layer and a convex body, wherein the convex body is a parabolic body which is obtained by rotating the parabolic mirror body along a symmetry axis of the parabolic mirror body, the quantum dot materials are arranged at the position of a focus of the parabolic mirror body, the quantum dot materials can emit collimated light after being excited, the surface, provided with the convex body, of the base material layer is a first surface, the surface opposite to the first surface is a second surface, the orthographic projection from the parabolic mirror body to the base material layer is circular, the radius of the circular shape is z, the distance from the focus of the parabolic mirror body to the second surface of the base material layer is h, and the range of arctan (z.

2. The quantum dot structure of claim 1, wherein the protrusions are arrayed on a substrate layer.

3. The quantum dot structure of claim 1, wherein each of the protrusions comprises a plurality of quantum dot materials of different colors, and after the quantum dot materials in each protrusion are excited by non-visible light, the light emitted from the quantum dot materials are mixed into white light.

4. The quantum dot structure of claim 1, wherein a plurality of retro-reflective structures are disposed at a portion of the second side of the substrate layer for retro-reflecting the non-collimated light from the second side of the substrate layer.

5. The quantum dot structure of claim 4, wherein each of the paraboloids is provided with a retro-reflective structure, the retro-reflective structure is annular, and the orthographic projection of the paraboloid to the substrate layer falls within a range enclosed by the orthographic projection of the retro-reflective structure to the substrate layer.

6. The quantum dot structure of claim 5, wherein the substrate layer has a thickness y, the parabolic body has a focal length of (1/2) P, the parabolic body has a focal point that is a distance r from the first face of the substrate layer, and the retroreflective structure has a ring width x in a direction parallel to the second face, wherein x is y (P + r)/r.

7. A backlight module comprising a backlight and a quantum dot structure according to any one of claims 1 to 6.

8. The backlight module as claimed in claim 7, wherein the backlight source comprises a light guide plate and a light source, the quantum dot structure is disposed on one side of the light emitting surface of the light guide plate, the protrusions are disposed closer to the light guide plate than the substrate layer, and the light source can excite quantum dot materials with multiple colors.