CN111679503A

CN111679503A - Backlight module and display device

Info

Publication number: CN111679503A
Application number: CN202010596302.5A
Authority: CN
Inventors: 张鹏
Original assignee: Wuhan China Star Optoelectronics Technology Co Ltd
Current assignee: Wuhan China Star Optoelectronics Technology Co Ltd
Priority date: 2020-06-28
Filing date: 2020-06-28
Publication date: 2020-09-18

Abstract

The present disclosure provides a backlight module and a display device. The backlight module comprises a light source, a light guide plate, an optical diaphragm and a shading film, wherein the light source is arranged on one side of the light guide plate, and the optical diaphragm is arranged above the light guide plate. The backlight module is provided with a through hole, and the through hole penetrates through the light guide plate and the optical diaphragm. The light guide plate comprises a body and a first protruding part, wherein the first protruding part is arranged on the body, and the first protruding part surrounds the through hole. The shading film is arranged on the surface of the first protruding part facing the through hole and the inner wall of the body penetrated by the through hole. The problem that the display picture has shadows due to the design of the retaining wall of the conventional backlight module is solved.

Description

Backlight module and display device

Technical Field

The disclosure relates to the field of display technologies, and in particular, to a backlight module and a display device.

Background

With the development of liquid crystal display technology, especially the development of full-screen technology, in order to realize a full-screen display, a Backlight Unit (BLU) of a conventional display device, such as a mobile phone, is generally designed as a hole (hole) in a plane, which is used as a placement area for devices, such as a camera. As shown in the display device 900 of fig. 1, the backlight module 1 is located below the display panel 2, a lower polarizer 3 is attached between the backlight module 1 and the display panel 2, and an upper polarizer 4 is attached on the display panel 2. The inner side of the through hole of the backlight module 1 adopts the structural design of the iron frame back plate 11 and the rubber frame retaining wall 12 to prevent dust from entering the inside of the backlight module 1 to influence the picture display of the display panel 2. Meanwhile, the iron frame back plate 11 and the rubber frame retaining wall 12 can support the thickness space of each diaphragm 13 of the backlight module 1, and the diaphragm 13 is prevented from being locally deformed during backlight circular testing experiments. And the iron frame back plate 11 and the rubber frame retaining wall 12 can also prevent light inside the backlight from entering the through hole area when the backlight works, and the shooting effect of the camera 5 is influenced. However, if such a structure is applied to an under-screen camera structure with a display effect, due to the existence of the iron frame back plate 11 and the rubber frame retaining wall 12, a more obvious shadow is displayed above the retaining wall, so that the display image is seriously layered.

Therefore, the problem of the display image appearing with shadows due to the retaining wall design of the conventional backlight module needs to be solved.

Disclosure of Invention

The disclosure provides a backlight module and a display device, which are used for solving the technical problem that a display picture has a shadow due to the retaining wall design of the conventional backlight module.

In order to solve the above problems, the technical solution provided by the present disclosure is as follows:

the embodiment of the disclosure provides a backlight module, which includes a light source, a light guide plate, an optical film and a light shielding film. The light source is arranged on one side of the light guide plate, and the optical film is arranged above the light guide plate. The backlight module is provided with a through hole, and the through hole penetrates through the light guide plate and the optical diaphragm. The light guide plate comprises a body and a first protruding part, wherein the first protruding part is arranged on the body, and the first protruding part surrounds the through hole. The shading film is arranged on the surface of the first protruding part facing the through hole and the inner wall of the position of the body penetrated by the through hole.

In the backlight module provided by the embodiment of the disclosure, the surface shape of the first protrusion comprises a circular ring.

In the backlight module provided by the embodiment of the disclosure, the width of the first protrusion is greater than or equal to 0.2 mm.

In the backlight module provided by the embodiment of the disclosure, the surface of the first protrusion facing the through hole coincides with the shape of the through hole.

In the backlight module provided by the embodiment of the disclosure, the thickness of the light shielding film ranges from 0.01 mm to 0.1 mm.

In the backlight module provided by the embodiment of the disclosure, the color of the light shielding film includes gray.

In the backlight module provided by the embodiment of the disclosure, the backlight module further includes a reflector plate, the reflector plate is disposed below the light guide plate, and the through hole penetrates through the reflector plate.

In the backlight module provided by the embodiment of the present disclosure, the backlight module further includes a back plate, the back plate includes an accommodating cavity, the accommodating cavity is used for accommodating the light source, the light guide plate and the optical film, and the through hole penetrates through the accommodating cavity.

In the backlight module provided by the embodiment of the disclosure, the light guide plate further includes a second protruding portion, the second protruding portion is disposed under the body and opposite to the first protruding portion, and the second protruding portion contacts with the back plate.

The present disclosure also provides a display device, which includes the backlight module, the liquid crystal display panel, the upper polarizer disposed on the liquid crystal display panel away from the backlight module, and the lower polarizer disposed between the liquid crystal display panel and the backlight module, wherein the upper polarizer and the lower polarizer have openings in areas corresponding to the through holes.

The beneficial effects of this revelation do: in the backlight module and the display device provided by the disclosure, the light guide plate comprises a body and a first protruding part, and the first protruding part surrounds the through hole of the backlight module. The first bulge can provide emergent light for the display panel while supporting the optical film of the backlight module, so that the display panel can normally display in an area corresponding to the first bulge, and the problem that the display picture is layered due to the fact that the display picture is dark due to the retaining wall design of the existing backlight module is solved. The peripheral frame of the through hole of the backlight module is reduced equivalently, and the application of the camera structure under the screen with the display function is facilitated. And meanwhile, the first protruding part close to the through hole of the backlight module and the inner wall of the body are coated with shading films in an evaporating mode, so that the situation that the backlight leaks to the through hole of the backlight module from the light guide plate to influence the camera shooting effect is avoided.

Drawings

In order to illustrate the embodiments or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the invention, and it is obvious for a person skilled in the art that other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic view of a retaining wall structure of a backlight module in the prior art;

fig. 2 is a schematic bottom view of a backlight module according to an embodiment of the disclosure;

FIG. 3 is a schematic diagram of a first side view structure of a backlight module according to an embodiment of the disclosure;

FIG. 4 is a schematic side view of a partial structure of a backlight module according to an embodiment of the disclosure;

FIG. 5 is a schematic diagram of a second side view structure of a backlight module according to an embodiment of the disclosure;

fig. 6 is a schematic side view of a display device according to an embodiment of the disclosure.

Detailed Description

The following description of the various embodiments refers to the accompanying drawings, which illustrate specific embodiments in which the disclosure may be practiced. Directional phrases used in this disclosure, such as [ upper ], [ lower ], [ front ], [ back ], [ left ], [ right ], [ inner ], [ outer ], [ side ], etc., refer only to the directions of the attached drawings. Accordingly, the directional terms used are used for the purpose of illustration and understanding of the present disclosure, and are not used to limit the present disclosure. In the drawings, elements having similar structures are denoted by the same reference numerals.

In one embodiment, a backlight module 100 is provided, such as the backlight module 100 shown in fig. 2, which is provided with a through hole 10, wherein the through hole 10 penetrates through the backlight module 100. The through hole 10 is used for placing functional elements such as a camera.

Specifically, as shown in fig. 3, which is a schematic cross-sectional view along a-a direction in fig. 2, in fig. 3, the backlight module 100 includes a light source 20, a light guide plate 30, an optical film 40 and a light shielding film 50. The light source 20 is disposed on one side of the light guide plate 30, but the disclosure is not limited thereto, and the light source may be a direct type light source. The optical film 40 is disposed above the light guide plate 30. The backlight module 100 is provided with a through hole 10, and the through hole 10 penetrates through the light guide plate 30 and the optical film 40. The light guide plate 30 includes a body 31 and a first protrusion 32, and the first protrusion 32 is disposed on the body 31. And the first protrusion 32 surrounds the through hole 10, and the first protrusion 32 is spaced from the body 31 by a dotted line, as shown in fig. 3. The light shielding film 50 is disposed on a surface of the first protrusion 32 facing the through hole 10 and an inner wall of the body 31 penetrated by the through hole.

Specifically, the backlight module 100 further includes a reflective sheet 60, and the reflective sheet 60 is disposed below the light guide plate 30.

Further, the through hole 10 of the backlight module 100 penetrates through the backlight module 100, that is, the through hole 10 penetrates through the optical film 40, the light guide plate 30 and the reflective sheet 60 on the backlight module 100.

Specifically, the optical film 40 includes a diffusion sheet 41, an upper brightness enhancement film 42, a lower brightness enhancement film 43, and the like. The optical film 40 is disposed above the light guide plate 30, that is, the optical film 40 is disposed on a light emitting surface of the light guide plate 30. It should be noted that, in the present disclosure, the upper side of the light guide plate 30 and the lower side of the light guide plate 30 are only used for convenience of describing the position relationship between the optical film 40, the reflective sheet 60 and the light guide plate 30, wherein the upper side of the light guide plate 30 refers to the light emitting surface of the light guide plate 30, and the lower side of the light guide plate 30 refers to the surface away from the light emitting surface of the light guide plate 30. And the light emitting surface of the light guide plate 30 herein refers to the light emitting surface of the light guide plate body 31.

Furthermore, the main body 31 of the light guide plate 30 is disposed parallel to the optical film 40 and the reflective sheet 50, and the first protrusion 32 of the light guide plate 30 is disposed perpendicular to the optical film 40 and the reflective sheet 60. Of course, the disclosure is not limited thereto, and the first protrusion 32 of the light guide plate 30, the optical film 4 and the reflective sheet 60 may also be disposed at an angle.

Specifically, the first protrusion 32 of the light guide plate 30 is disposed on the body 31 of the light guide plate 30, that is, the first protrusion 32 is formed by the body 31 extending toward the light emitting direction of the body 31. The first protrusion 32 surrounds the through hole 10 of the backlight module. The surface of the first projecting portion 32 facing the through-hole 10 coincides with the shape of the through-hole. Since the through hole 10 is a cylindrical through hole, the first protrusion 32 is a hollow cylinder, that is, the inner diameter of the first protrusion 32 is the inner diameter of the through hole 10 of the backlight module, and further, the hollow portion of the first protrusion 32 is overlapped with the through hole 10 of the backlight module. Specifically, as shown in fig. 2, the surface shape of the first projecting portion 32 is a circular ring, where the surface shape refers to a shape of a cross section perpendicular to a center line of the hollow cylindrical outer shape of the first projecting portion; as shown in fig. 3, the first projecting portion 32 has a rectangular longitudinal cross-sectional shape, where the longitudinal cross-section is a cross-section parallel to the center line of the first projecting portion.

Further, the through hole 10 of the backlight module 100 penetrates through the optical film 40, the light guide plate 30 and the reflective sheet 60, so that the film layers of the optical film 40, the reflective sheet 60 and the like are not stable on the light guide plate 30. The first protrusion 32 of the light guide plate 30 of the present disclosure may be used to fix the film layers. So can need not set up the backplate and glue the frame and fix each rete, practice thrift manufacturing cost, can avoid backlight unit to lead to the problem that each rete warp when doing the ring test (the ring test includes tests relevant with the environment such as high temperature and high humidity, high temperature storage, cold and hot shock) simultaneously. Of course, since the reflective sheet 60 is located under the light guide plate 30 and does not contact with the first protrusion 32, the reflective sheet 60 may be fixed under the light guide plate 30 by an adhesive method. Or another protrusion may be formed under the body 31 of the light guide plate 30 for fixing the reflective sheet 60.

Specifically, as shown in fig. 4, the width D1 of the first protrusion 32 is greater than or equal to 0.2 mm, and the height H of the first protrusion 32 needs to be greater than or equal to the thickness of the optical film so as to fix the optical film.

Further, the light guide plate 30 is made of a transparent material, and the transparent material includes Polycarbonate (PC), polymethyl methacrylate (PMMA), and tempered glass.

Further, a light shielding film 50 is disposed on a surface of the first protrusion 32 facing the through hole 10 of the backlight module and an inner wall of the body 31 penetrated by the through hole 10. The light shielding film 50 is used for shielding light in the light guide plate 30 from leaking into the through hole 10 of the backlight module. Specifically, the light emitted from the light source 20 is irradiated onto the light guide plate 30, and the light is transmitted through reflection, refraction, and the like in the light guide plate 30 and is emitted from the light emitting surface of the body 31 and the first protruding portion 32. The light emitting surface of the first protrusion 32 is parallel to the light emitting surface of the body 31, and the light emitting directions are the same. It can be understood that, since there is no optical film above the first protrusion 32, there is a certain difference between the light emitted from the first protrusion 32 and the light emitted from the body 31. The difference can be adjusted by adjusting the transmittance of the display panel corresponding to the upper side of the first protrusion, and of course, other means can be used to compensate the difference.

Further, the light source 20 includes a blue LED or the like. Meanwhile, the light leaked from the light guide plate 30 and the light reflected from the upper optical film 40 can be reflected back along the light exit direction of the light guide plate 30 by the reflective sheet 60, so that the utilization rate of the light can be greatly improved. The light shielding film 50 also plays a role in improving the utilization rate of light while blocking the light of the light guide plate 30 from leaking into the through hole 10 of the backlight module.

Specifically, the light-shielding film 50 may be formed by depositing a light-shielding material on the inner walls of the first protrusion 32 and the body 31 by a vacuum deposition process. The light shielding film 50 covers the surface of the first protrusion 32 facing the through-hole 10 and the entire inner wall of the body 31. The thickness D2 of the light-blocking film 50 may range between 0.01 mm and 0.1 mm.

Further, the color of the light-shielding film 50 may be other colors such as gray. The light-shielding film 50 blocks light from passing through and is made of opaque material, and certainly, the light-shielding film of the present disclosure may also be made of micro-transparent material, so as not to affect the normal operation of functional elements such as cameras in the through holes.

In the present disclosure, a film is coated on a surface of the first protrusion 32 facing the through hole 10 and an inner wall of the body 31 penetrated by the through hole to form the light shielding film 50, so as to prevent light in the light guide plate 30 from leaking into the through hole 10 of the backlight module. However, the disclosure is not limited thereto, and those skilled in the art may also use a light shielding tape or other light shielding elements to adhere to the surface of the first protrusion facing the through hole and the inner wall of the body penetrated by the through hole, so as to achieve the purpose of shielding light.

In this embodiment, the structure of the light guide plate is redesigned, and the optical film of the backlight module can be fixed by arranging the first protruding part, so that a back plate and a rubber frame are not needed, and the cost is saved. Meanwhile, light rays pass through the first protruding portion, when the display panel is applied to the camera structure under the screen with the display function, the display panel normally displays the area corresponding to the first protruding portion, and the problem that the display picture is layered due to the fact that the display picture is shaded due to the fact that the retaining wall of the existing backlight module is designed is solved.

In one embodiment, different from the above embodiments, the backlight module 101 shown in fig. 5 further includes a back plate 70, and the back plate 70 includes a receiving cavity for receiving the light source 20, the light guide plate 30 ', the optical film 40, and the reflective sheet 60'. The through hole 10 of the backlight module 101 penetrates through the accommodating cavity of the back plate. The light guide plate 30' further includes a second protrusion 33, the second protrusion 33 is disposed under the body 31 and opposite to the first protrusion 32, and the second protrusion 33 contacts the back plate 70 to fix the back plate 70.

Specifically, the second protrusion 33 is disposed under the body 31 of the light guide plate 30, that is, the second protrusion 33 is formed by the body 31 extending in a light emitting direction away from the body 31. It is understood that, since the light guide plate 30 is formed with the second protrusion 33, the corresponding light shielding film 50' also covers the surface of the second protrusion 33 facing the through hole 10 to prevent light leakage from the second protrusion 33.

Further, the second protrusion 33 also surrounds the through hole 10 of the backlight module 101. Since the through hole 10 is a cylindrical through hole, the second protrusion 33 is also a hollow cylinder. It is understood that the through hole 10 of the backlight module 101 also penetrates through the back plate 70, and the second protrusion 33 can fix the back plate 70 near the area of the through hole 10. Meanwhile, the second protrusion 33 may fix the reflective film 60' near the region of the through hole 10. The fixing mode of fixing the back plate and the reflection diaphragm by the second bulge can adopt that a groove is arranged on the second bulge, and the back plate and the reflection diaphragm are clamped and fixed with the groove. Of course, the fixing manner of the present disclosure is not limited thereto.

Further, the back plate 70 may be a metal back plate or a plastic-iron integrated structure. For other descriptions, please refer to the above embodiments, which are not repeated herein.

In an embodiment, as shown in fig. 6, a display device 1000 is provided, which includes the backlight module 100, the liquid crystal display panel 200, the upper polarizer 400 disposed on the liquid crystal display panel 200 and away from the backlight module 100, and the lower polarizer 300 disposed between the liquid crystal display panel 200 and the backlight module 100, wherein the upper polarizer 400 and the lower polarizer 300 are opened in an area corresponding to the through hole 10. Of course, the display device 1000 further includes a cover plate disposed on the upper polarizer, etc., which will not be described one by one.

According to the above embodiments:

the invention provides a backlight module and a display device. The backlight module is provided with a through hole, and the through hole penetrates through the light guide plate and the optical diaphragm. The light guide plate comprises a body and a first protruding part, wherein the first protruding part is arranged on the body, and the first protruding part surrounds the through hole. The first bulge can provide emergent light for the display panel while supporting the optical film of the backlight module, so that the display panel can normally display in an area corresponding to the first bulge, and the problem that the display picture is layered due to the fact that the display picture is dark due to the retaining wall design of the existing backlight module is solved. The peripheral frame of the through hole of the backlight module is reduced equivalently, and the application of the camera structure under the screen with the display function is facilitated. And meanwhile, the first protruding part close to the through hole of the backlight module and the inner wall of the body are coated with shading films in an evaporating mode, so that the situation that the backlight leaks to the through hole of the backlight module from the light guide plate to influence the camera shooting effect is avoided.

In summary, although the present disclosure has been described with reference to the preferred embodiments, the above-described preferred embodiments are not intended to limit the present disclosure, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, so that the scope of the present disclosure is defined by the appended claims.

Claims

1. A backlight module is characterized by comprising a light source, a light guide plate, an optical diaphragm and a shading film, wherein the light source is arranged on one side of the light guide plate, the optical diaphragm is arranged above the light guide plate, and the backlight module is provided with a through hole which penetrates through the light guide plate and the optical diaphragm;

the light guide plate comprises a body and a first protruding part, wherein the first protruding part is arranged on the body and surrounds the through hole; and

the shading film is arranged on the surface of the first protruding part facing the through hole and the inner wall of the position of the body penetrated by the through hole.

2. A backlight module according to claim 1, wherein the first protrusions have a surface shape comprising a circular ring.

3. The backlight module as claimed in claim 2, wherein the width of the first protrusion is greater than or equal to 0.2 mm.

4. A backlight module according to claim 1, wherein the surface of the first projection facing the through hole coincides with the shape of the through hole.

5. The backlight module as claimed in claim 4, wherein the thickness of the light shielding film ranges from 0.01 mm to 0.1 mm.

6. A backlight module according to claim 4, wherein the color of the light blocking film comprises gray.

7. The backlight module according to claim 1, further comprising a reflective sheet disposed under the light guide plate, wherein the through hole penetrates the reflective sheet.

8. The backlight module according to claim 1, further comprising a back plate, wherein the back plate comprises a receiving cavity for receiving the light source, the light guide plate and the optical film, and the through hole penetrates through the receiving cavity.

9. The backlight module according to claim 8, wherein the light guide plate further comprises a second protrusion disposed under the body opposite to the first protrusion, and the second protrusion contacts the back plate.

10. A display device, comprising the backlight module according to any one of claims 1 to 9, a liquid crystal display panel, an upper polarizer disposed on a surface of the liquid crystal display panel away from the backlight module, and a lower polarizer disposed between the liquid crystal display panel and the backlight module, wherein the upper polarizer and the lower polarizer are opened in an area corresponding to the through hole.