CN216411624U

CN216411624U - Light guide plate, backlight module and display device

Info

Publication number: CN216411624U
Application number: CN202121742685.9U
Authority: CN
Inventors: 刘欣; 邹文聪; 李圣; 尤君平; 陈伟雄
Original assignee: Shenzhen Skyworth RGB Electronics Co Ltd
Current assignee: Shenzhen Skyworth RGB Electronics Co Ltd
Priority date: 2021-07-28
Filing date: 2021-07-28
Publication date: 2022-04-29
Anticipated expiration: 2031-07-28

Abstract

The utility model discloses a light guide plate, a backlight module and display equipment, wherein the light guide plate comprises a plate body and a light guide part, wherein the plate body comprises a light incident surface, a light shading surface and a light emergent surface; the light guide part is printed on the light shading surface, and the contact surface of the light guide part and the light shading surface is of an annular structure. Utility model technical scheme can improve the rendition rate of light guide part.

Description

Light guide plate, backlight module and display device

Technical Field

The utility model relates to the technical field of display, in particular to a light guide plate, a backlight module applying the light guide plate and display equipment applying the backlight module.

Background

With the development of technology, the thickness of various display devices is gradually reduced. The thickness of the display equipment is affected by the backlight module, and the backlight module is divided into a direct type and a side type according to the distribution of the light source positions. The direct type backlight source has thick product thickness and large volume; the light source of the side-in backlight source is arranged on one side of the light guide plate, so that the size of the display equipment can be effectively reduced, and the side-in backlight module is generally adopted in the industry at present.

The conventional side-in backlight module generally comprises a light guide plate, a diffusion sheet, a prism sheet, a light source, a reflection sheet, a backlight plate, and the like. The light guide plate is a core component of the side-in type backlight module and mainly used for converting a point light source or a line light source into a uniform surface light source for display. In the set of light source conversion system, the mesh points (as light guide structures) at the bottom of the light guide plate play an important role, and the mesh points break the regular total reflection of light energy in the light guide plate to form emergent light energy.

The printing ink transfers the mesh points to the surface of the light guide plate through a screen printing technology, namely a mesh point surface is formed. In the actual printing process, the traditional printing dot process is affected by the process precision, the problems of shrinkage, defects and the like of small dots often occur, and the actual dot area is smaller than the design area, so that the dot transfer rate is lower than 100%.

SUMMERY OF THE UTILITY MODEL

The utility model mainly aims to provide a light guide plate, aiming at improving the transfer printing rate of a light guide part.

In order to achieve the above object, the present invention provides a light guide plate comprising:

the plate body comprises a light incident surface, a light shading surface and a light emergent surface; and

the light guide parts are printed on the light shading surface, and the contact surfaces of the light guide parts and the light shading surface form an annular structure.

Optionally, the light guide part is arranged to protrude in a direction away from the light exit surface of the light shielding surface, and an outer diameter of the light guide part is gradually reduced.

Optionally, the light-intensity strongest region illuminated by the light-incident surface on the light-shielding surface faces the light-intensity weakest region illuminated by the light-incident surface on the light-shielding surface, and the distance between two adjacent light guide portions is reduced.

Optionally, the light guide portion gradually increases in volume from a region with the strongest light intensity, which is irradiated by the light incident surface onto the light shielding surface, to a region with the weakest light intensity, which is irradiated by the light incident surface onto the light shielding surface.

Optionally, the light guide part and the light shielding part have the same inner diameter and larger outer diameter at the contact surface from the region with the strongest light intensity, which is irradiated on the light shielding surface by the light incident surface, to the region with the weakest light intensity, which is irradiated on the light shielding surface by the light incident surface.

Optionally, the light-guiding surface and the light-shielding surface have the same inner diameter and the same or different outer diameter, and the light-guiding surface and the light-shielding surface have the same inner diameter and the same outer diameter.

Optionally, a reflector plate is disposed on a side of the light-shielding surface away from the light-emitting surface, at least one through hole is disposed on the reflector plate, the through holes correspond to the light-guiding portions one to one, and the light-guiding portions are accommodated in the through holes.

Optionally, the plate body is flat.

The utility model also provides a backlight module which comprises a light source and the light guide plate.

The utility model also provides a display device which comprises a display panel and the backlight module.

According to the technical scheme, the light guide part which is in an annular shape with the contact surface is printed on the shading surface of the light guide plate, so that the light guide part and the effective light guide surface of the shading surface are in an annular structure, compared with the traditional effective light guide surface with a circular structure, on one hand, the closed area of the light guide part is enlarged, the equivalent light guide effective area is obtained, and the reflection effect of a light source is ensured; on the other hand, the printing ink printing process precision is improved, the problems of pinch points, residual defects and the like of the traditional light guide part are avoided, the transfer printing rate of the light guide part is improved, the light energy utilization rate of a backlight system is improved, and the effects of brightness, uniformity, subjective visual effect and the like of a display picture of display equipment are ensured; on the other hand, the enlarged closed area of the light guide part enables the printing volume of a single light guide part to be enlarged, the problem that the printing ink is plugged in the net due to printing of the light guide part with small volume is avoided, and further frequent cleaning of the screen plate is avoided, so that the production efficiency is improved.

Drawings

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

FIG. 1 is a schematic structural diagram of a light guide plate according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of an embodiment of a light guide portion in the light guide plate in FIG. 1;

FIG. 3 is a schematic structural view of an embodiment of a light guide plate and a reflective sheet.

The reference numbers illustrate:

reference numerals	Name (R)	Reference numerals	Name (R)
				100	Light guide plate	120	Light guide part
110	Plate body	121	Inner ring
				111	Light incident surface	122	Outer ring
112	Shading surface	200	Reflector plate
				113	Light emitting surface	210	Through hole

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly.

In addition, the descriptions related to "first", "second", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In addition, "and/or" in the whole text includes three schemes, taking a and/or B as an example, including a technical scheme, and a technical scheme that a and B meet simultaneously; in addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

The light guide plate 100 is a core component of the edge-type backlight module, and mainly functions to convert a point light source or a line light source into a uniform surface light source for display. The light guide plate 100 has a light incident surface 111, a light shielding surface 112 and a light emitting surface 113, and the light guide part 120 is distributed on the light guide plate 100, and the working principle is as follows: external light enters through the light incident surface 111 of the light guide plate 100, the general external light is scattered by the light incident surface 111 of the light guide plate 100 when entering the light incident surface 111, the light entering the light guide plate 100 is primarily scattered and spread, the light which is primarily scattered passes through the light guide part 120 on the light guide plate 100, the scattering effect of the light guide part 120 is used for changing the linear light source into the surface light source, and the linear light source is emitted through the light emitting surface 113 after being changed into the surface light source, so that an even picture is formed on the display device.

In the light source conversion system, the light guide part 120 at the bottom of the light guide plate 100 plays an important role in breaking the regular total reflection of light energy inside the light guide plate 100 to form emergent light energy. The ink transfers the light guide part 120 to the surface of the light guide plate 100 by a screen printing technique, and the light guide part 120 is formed in a certain arrangement on the surface of the light guide plate 100. The printed light guide part 120 of the conventional light guide plate 100 is an outward-protruding cone-like structure, and the contact surface between the light guide plate 100 and the printed light guide part has optical effect, i.e. an effective light guide surface. In the actual printing process, the conventional process for printing the light guide part 120 is affected by the process precision, the light guide part 120 with a small volume often has the problems of shrinkage points, defects and the like, the actual light guide area is smaller than the design area, that is, the transfer printing rate of the light guide part 120 is smaller than 100%, which causes the problems of brightness, uniformity, subjective visual effect and the like, and the light energy utilization rate of the backlight system is seriously affected. In addition, in the printing process, the ink can continuously block the small meshes of the screen plate, the problem of screen blocking by the ink often occurs, the screen plate needs to be cleaned frequently, and the production efficiency is seriously influenced. Accordingly, the present invention provides a light guide plate 100 for a backlight module (not shown).

Referring to fig. 1, in an embodiment of the utility model, the light guide plate 100 includes a plate body 110 and a light guide part 120, where the plate body 110 includes a light incident surface 111, a light shielding surface 112, and a light emitting surface 113. The shape of the light guide plate 100 includes a flat plate shape and a wedge shape, in the side-type backlight module, the light guide plate 100 is generally a flat plate shape, and the light source is disposed on a side surface of the plate body 110 of the light guide plate 100. The plate body 110 may be made of optical grade acrylic (PMMA) or Polycarbonate (PC) plate. In one embodiment, both side surfaces of the plate body 110 are light incident surfaces 111, which can provide more incident light sources for the light guide plate 100. The plate body 110 is made of a transparent acrylic plate, and has high light transmittance, high reflectivity and no light absorption.

Referring to fig. 2, the light guide part 120 is printed on the light shielding surface 112 by a screen printing technique, and a contact surface between the light guide part 120 and the light shielding surface 112 is a ring structure. In the light source conversion system, the contact surface between the light guide part 120 and the light shielding surface 112 has an optical effect, i.e., an effective light guide surface. The annular structure comprises an inner ring 121 and an outer ring 122, wherein the inner ring 121 is a blank area, namely, no ink is printed in the area of the inner ring 121; the annular structure between the inner ring 121 and the outer ring 122 is an effective light guiding surface, i.e. ink is printed in the annular region. The annular structure may be a circular ring, polygonal ring, or the like. In one embodiment, the ring structure is a circular ring structure. As a design requires light guide 120 having an effective area S, the outer ring 122 has a radius R2, the inner ring 121 has a radius R1, and the effective area S of light guide 120 is pi (R2)²-R1²) By adjusting the reasonable selection of R2 and R1The light guide area of the design target can be obtained.

According to the technical scheme, the light guide part 120 with the annular contact surface is printed on the shading surface 112 of the light guide plate 100, so that the effective light guide surface of the light guide part 120 is in an annular structure, and compared with the traditional effective light guide surface with a circular structure, on one hand, the equivalent light guide effective area is obtained by enlarging the closed area of the light guide part 120, and the reflection effect of a light source is ensured; on the other hand, the printing ink printing process precision is improved, the problems of pinch points, residual defects and the like of the traditional light guide part 120 are avoided, the transfer printing rate of the light guide part 120 is improved, the light energy utilization rate of a backlight system is improved, and the brightness, the uniformity, the subjective visual effect and other effects of a display picture of the display equipment are ensured; on the other hand, the enlarged closed area of the light guide part 120 increases the printing volume of a single light guide part 120, thereby avoiding the problem of ink net blocking caused by printing of the light guide part 120 with small volume, and further avoiding frequent cleaning of the screen plate, thereby improving the production efficiency.

Referring to fig. 1, the light guide part 120 is formed by printing ink on the light shielding surface 112, and the light guide part 120 is protruded in a direction away from the light emitting surface 113 on the light shielding surface 112 and the outer diameter of the light guide part 120 is gradually reduced. That is, the light guide part 120 has a certain height above the light shielding plate, and the outer diameter of the light guide part 120 is different between the side of the light shielding surface 112 contacting the light emitting surface 113 and the side away from the light emitting surface 113. Thus, the inner ring 121 of the light guide part 120 is a blank region, the annular structure between the outer ring 122 and the inner ring 121 of the light guide part 120 is protruded, and a groove is formed between the middle part of the annular light guide part 120 and the smooth light shielding surface 112. The light guide part 120 may have a plurality of protruding structures on a side away from the light exit surface 113, and if the contact surface between the light guide part 120 and the light blocking surface 112 is a circular ring structure, the protruding structure of the light guide part 120 on the side away from the light exit surface 113 is a circular truncated cone structure; when the contact surface between the light guide portion 120 and the light shielding surface 112 is a polygonal ring structure, the protrusion of the light guide portion 120 facing away from the light emitting surface 113 is a frustum structure. Thus, the incident light can be reflected by the reflection surface of the light guide part 120 and projected out of the light exit surface 113 of the plate body 110 of the light guide plate 100, thereby improving the reflection efficiency.

Further, to improve the uniformity of the reflective light source, the region with the strongest light intensity irradiated on the light shielding surface 112 by the light incident surface 111 faces the region with the weakest light intensity irradiated on the light shielding surface 112 by the light incident surface 111, the distance between two adjacent light guide portions 120 is reduced, and the volume of the light guide portions 120 is gradually increased. That is, the light guide part 120 is arranged on the light shielding surface 112 such that the light incident side is small and thin and the light emitting side is large and dense. In particular, the method comprises the following steps of,

the light-intensity-strongest region irradiated on the light-shielding surface 112 from the light-incident surface 111 is directed toward the light-intensity-weakest region irradiated on the light-shielding surface 112 from the light-incident surface 111, and the inner diameter of the contact surface between the light-guiding portion 120 and the light-shielding surface 112 is the same, while the outer diameter is increased, thereby increasing the effective area of the light-guiding portion 120. Alternatively, the light guide 120 may have an increased effective area by reducing the inner diameter of the contact surface between the light guide 120 and the light blocking surface 112 and keeping the outer diameter constant or larger in the region where the light intensity is the strongest when the light incident surface 111 strikes the light blocking surface 112 to the region where the light intensity is the weakest when the light incident surface 111 strikes the light blocking surface 112. However, in the conventional printing process, the current state of the art of screen printing is limited,

the following design of light guide 120 often fails, which reduces the transfer efficiency η of light guide 120 to less than 80%, and in one embodiment, the inner diameter of light guide 120 is maintained at 0.25mm or more. Therefore, the reflection uniformity of the light source can be better, and the brightness, the uniformity and the subjective visual effect of the display picture of the display equipment are further better.

Referring to fig. 3, in order to further improve the utilization efficiency of the light source, a reflective sheet 200 is disposed on the light-shielding surface 112 side of the plate body 110, and the reflective sheet 200 can reflect the light exposed from the light-shielding surface 112 back into the plate body 110, so as to improve the utilization efficiency of the light. However, during vibration test, transportation and transportation, the light guide part 120 of the conventional printed light guide plate 100 is easily rubbed against the reflective sheet 200, which may damage the light guide part 120. Therefore, the light shielding surface 112 is provided with a reflective sheet 200 on a side away from the light emitting surface 113, the reflective sheet 200 is provided with at least one through hole 210, the through holes 210 correspond to the light guide portions 120 one by one, and the through holes 210 accommodate the light guide portions 120. The reflector sheet 200 is provided with the through hole 210 to avoid the light guide part 120, so that friction caused by relative movement between the light guide part 120 and the reflector sheet 200 in vibration tests, transportation and transportation processes is avoided, damage to the light guide part 120 is avoided, and the light guide effect of the light guide part 120 is ensured.

The present invention further provides a backlight module (not shown), which includes a light source (not shown) and a light guide plate 100, and the specific structure of the light guide plate 100 refers to the above embodiments, and since the backlight module adopts all technical solutions of all the above embodiments, the backlight module at least has all the beneficial effects brought by the technical solutions of the above embodiments, and details are not repeated herein. The light source is disposed on a side surface of the light guide plate 100, and specifically includes an Electroluminescence (EL) light source, a small Cold Cathode Fluorescent Lamp (CCFL), an LED light source, and the like.

The present invention further provides a display device (not shown), which includes a display panel (not shown) and a backlight module, the specific structure of the backlight module refers to the above embodiments, and since the light guide plate 100 in the backlight module adopts all technical solutions of all the above embodiments, at least all the beneficial effects brought by the technical solutions of the above embodiments are achieved, and no further description is given here.

The above description is only an alternative embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which are made by the contents of the present specification and the accompanying drawings, or directly/indirectly applied to other related technical fields, are included in the scope of the present invention.

Claims

1. A light guide plate, comprising:

the light guide parts are printed on the light shading surface, the contact surfaces of the light guide parts and the light shading surface form an annular structure, the annular structure comprises an inner ring and an outer ring, printing ink is not arranged in the inner ring, and printing ink is arranged between the inner ring and the outer ring.

2. The light guide plate according to claim 1, wherein the light guide portion is convexly disposed in a direction away from the light exit surface in the light blocking surface and has an outer diameter that gradually decreases.

3. The light guide plate according to claim 1, wherein the light guide portion has a light intensity strongest region that is illuminated by the light incident surface on the light blocking surface, and a light intensity weakest region that is illuminated by the light incident surface on the light blocking surface, and a distance between two adjacent light guide portions decreases.

4. The light guide plate according to claim 1, wherein the light guide portion has a gradually increasing volume from a region of highest light intensity that the light incident surface irradiates on the light blocking surface to a region of lowest light intensity that the light incident surface irradiates on the light blocking surface.

5. The light guide plate according to claim 3 or 4, wherein the light guide portion has the same inner diameter as a contact surface of the light shielding surface and an increased outer diameter from a region of the maximum intensity of light irradiated from the light incident surface onto the light shielding surface to a region of the minimum intensity of light irradiated from the light incident surface onto the light shielding surface.

6. The light guide plate according to claim 3 or 4, wherein the light guide portion has a contact surface with the light shielding surface having a smaller inner diameter and a same or larger outer diameter, from the region of the strongest light intensity irradiated from the light incident surface onto the light shielding surface to the region of the weakest light intensity irradiated from the light incident surface onto the light shielding surface.

7. The light guide plate according to any one of claims 1 to 4, wherein a reflector is disposed on a side of the light shielding surface facing away from the light emitting surface, the reflector has at least one through hole, the through holes correspond to the light guide portions one to one, and the through holes receive the light guide portions.

8. The light guide plate according to claim 1, wherein the plate body has a flat plate shape.

9. A backlight module comprising a light source and the light guide plate according to any one of claims 1 to 8.

10. A display device, characterized in that the display device comprises a display panel and a backlight module according to claim 9.