WO2014124572A1

WO2014124572A1 - Backlight module and display device comprising same

Info

Publication number: WO2014124572A1
Application number: PCT/CN2013/074380
Authority: WO
Inventors: 陈秀云; 张志丹; 孙凌宇; 尹大根; 马文文; 张宇
Original assignee: 京东方科技集团股份有限公司; 北京京东方显示技术有限公司
Priority date: 2013-02-18
Filing date: 2013-04-18
Publication date: 2014-08-21
Also published as: CN103148413A

Abstract

A backlight module and a display device comprising the same. The backlight module comprises a light guide plate (1) having a bottom surface and a side surface (1A), a backplane (4), a light-emitting device, and a support member (5). The backplane (4) at least comprises a bottom portion (4B) disposed below the bottom of the light guide plate (1) and the light-emitting device, and a side portion (4A) which faces and is spaced from the side surface (1A) of the light guide plate (1). The light-emitting device comprises a light source (2) and a printed circuit board (3) electrically connected to the light source (2). The support member (5) supports the printed circuit board (3) and the light guide plate (1), and makes a spacing between a light-emitting surface of the light source (2) and the side surface (1A) of the light guide plate (1) greater than or equal to a set spacing.

Description

Backlight module and display device therewith

Technical field

Embodiments of the present invention relate to a backlight module and a display device. Background technique

Due to its small size, low power consumption and low radiation, liquid crystal displays have dominated the current flat panel display market. In the liquid crystal display, since the liquid crystal itself does not emit light, it only regulates the light. In order to display an image on the screen of the liquid crystal display, it is necessary to configure a backlight module (BLU, Back Light Unit) for the display panel (BLU). At present, with the increasing demand for large-size liquid crystal displays in the market, the development of large-size liquid crystal display technology has been stimulated, and the size of the backlight module has also been increased accordingly.

Generally, the backlight module can be divided into a side-in backlight module and a direct-lit backlight module according to different positions of the light source in the backlight module, wherein the light source in the side-in backlight module is located on the side of the display panel. The light source in the direct type backlight module is located at the bottom of the display panel. The side-lit backlight module is widely used in the industry due to its low cost and thin size.

As shown in FIG. 1 and FIG. 2, the conventional side-lit backlight module generally includes a light guide plate (LGP) 1 , and an optical film set disposed at the bottom of the light guide plate 1 is disposed on the side of the light guide plate 1 (ie, A plurality of light sources 2 on the light side, a printed circuit board (PCB) 3 electrically connected to the plurality of light sources 2, and a back cover 4 disposed at the bottom of the optical film group and the printed circuit board 3.

Wherein, when the light source 2 is an LED (Light Emitting Diode), if the distance between the light guide plate and the LED is too close, the light guide plate is expanded on the one hand (the size of the backlight module is larger, The greater the amount of expansion of the light plate), then expand outward to directly damage the LED, or when it is outwardly expanded, although it is not close to but close to the LED, it will be thermally deformed at the edge of the light guide plate near the LED, and the deformation The light guide plate may cause the optical film group or even the entire backlight module to be deformed, resulting in poor picture quality of the display; on the other hand, due to limitations of the LED illumination angle (generally 120°) and the like, the light emitted by each LED is located. The intensity of the light in the middle portion of the light is stronger, the brightness at the corresponding position on the light guide plate is brighter, and the light intensity at the intersection of the light emitted by the adjacent two LEDs is weaker, and the brightness at the corresponding position on the light guide plate is higher. Dark, so The Hotspot phenomenon (ie, unevenness of light and darkness) is generated on the light guide plate and a dark area is formed, thereby affecting the image quality of the display. In order to avoid or reduce the occurrence of the above phenomenon, the distance between the light guide plate and the LED is generally increased, that is, the distance between the light incident surface of the light guide plate and the light emitting surface of the LED is increased, but the light emitting angle of the LED is generally 120. Therefore, the light-in efficiency of the LED decreases as the distance between the light guide plate and the LED increases, thereby causing a decrease in the light energy utilization rate of the LED and an increase in the amount of light loss. Summary of the invention

An embodiment of the present invention provides a backlight module, including: a light guide plate having a bottom surface and a side surface; the back plate includes at least a bottom portion disposed under the bottom surface of the light guide plate and the light emitting device, and facing the a side of the side of the light guide plate spaced apart therefrom; a light emitting device comprising a light source and a printed circuit board electrically connected to the light source; and a support configured to support the printed circuit board at or equal to a setting spacing.

Embodiments of the present invention also provide a display device including the above backlight module.

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings to be used in the embodiments or the description of the prior art will be briefly described below. Obviously, the drawings in the following description relate only to the present invention. Some embodiments of the embodiments are not limiting of the embodiments of the invention.

1 is a schematic structural view of a conventional side-entry backlight module;

Figure 2 is a cross-sectional view taken along line A-A of Figure 1;

3 is a schematic structural view of a side-lit backlight module according to a first embodiment of the present invention; FIG. 4 is a cross-sectional view taken along line A-A of FIG. 3;

5 is a schematic structural view of a light-emitting device when the U-shaped flexible mechanism is used for the expandable member of FIG. 3; FIG. 6 is a schematic structural view of the light-emitting device when the expandable member of FIG. 3 adopts an S-shaped flexible mechanism; FIG. Schematic diagram of a light-emitting device when a left-right symmetric flexible mechanism is used;

8 is a schematic structural view of a side-entry backlight module according to a second embodiment of the present invention; FIG. 9 is a cross-sectional view taken along line A-A of FIG. 8;

FIG. 10 is a schematic structural diagram of a side-entry backlight module according to a third embodiment of the present invention; FIG. Figure 11 is a cross-sectional view taken along line AA of Figure 10;

Figure 12 is a cross-sectional view taken along line B-B of Figure 10;

13 is a schematic structural view of a side-lit backlight module according to a fourth embodiment of the present invention; FIG. 14 is a cross-sectional view taken along line A-A of FIG.

Figure 15 is a cross-sectional view taken along line B-B of Figure 13;

16 is a schematic structural view of a side-lit backlight module according to a fifth embodiment of the present invention; and FIG. 17 is a cross-sectional view taken along line A-A of FIG. 16;

Figure 18 is a cross-sectional view taken along line B-B of Figure 16 . detailed description

The technical solutions in the embodiments of the present invention will be described clearly and completely in detail with reference to the accompanying drawings, and the embodiments described herein are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present invention without departing from the scope of the present invention are within the scope of the embodiments of the present invention.

Unless otherwise defined, technical terms or scientific terms used herein shall be of the ordinary meaning understood by those of ordinary skill in the art to which the invention pertains. The words "first", "second" and similar terms used in the specification and claims of the present invention do not denote any order, quantity, or importance, but are merely used to distinguish different components. Similarly, the words "a" or "an" do not denote a quantity limitation, but rather mean that there is at least one. The words "including" or "comprising", etc., are intended to mean that the elements or objects preceding "including" or "comprising" are intended to encompass the elements or Component or object. "Upper", "Down", "Left", "Right", etc. are only used to indicate the relative positional relationship. When the absolute position of the object to be described is changed, the relative positional relationship may also change accordingly.

One of the technical problems to be solved by the embodiments of the present invention is to provide a backlight module capable of preventing a light source from being damaged when the light guide plate is inflated, or a light source that is too close to the light source, and a display device including the backlight module. . Another technical problem to be solved by the embodiments of the present invention is to provide a backlight module that can prevent the light source from damaging the light source when it is inflated, or is too close to the light source to cause the light guide plate to be thermally deformed, and to improve the light energy utilization rate of the light source. Group and including the backlight module Display device.

First embodiment:

As shown in FIG. 3 and FIG. 4, the embodiment provides a backlight module including a light guide plate 1, a light source 2, a printed circuit board 3, a back plate 4, and a support member 5.

The light guide plate 1 has a flat shape, and the bottom of the light guide plate 1 may be provided with light guide mesh points of different sizes and sizes, such as strips, triangles, dots or ellipsoidal light guide dots. The light emitted from the light source 2 is incident from the side of the light guide plate to the bottom thereof (for example, the lower portion of the light guide plate 1 shown in FIG. 4), and the light is scattered by the bottom light guide dot to form a uniform surface light source and emit light from the light guide plate 1. A face (for example, the upper surface of the light guide plate 1 shown in Fig. 4) is emitted.

One or more light sources 2 may be disposed on one side of the light guide plate 1. In the present embodiment, a plurality of light sources 2 are used, which are electrically connected to the printed circuit board 3, are uniformly and dispersedly disposed on the printed circuit board 3 along the side of the light guide plate 1, and along the length direction of the printed circuit board 3. Arranged in a straight line. The light source is, for example, a light emitting diode (LED). The plurality of light sources 2 and the printed circuit board 3 and the like electrically connected thereto constitute a light-emitting device, which is disposed to face the first side face 1A of the light guide plate 11. A light-emitting device including the light source 2, the printed circuit board 3, and the like may be disposed on one or more sides of the light guide plate 1.

The backboard 4 includes at least a bottom portion 4B disposed below the bottom surface of the light guide plate 11 and the light emitting device, and a side portion 4A facing the first side surface 1A of the light guide plate 1. The bottom portion 4B and the side portion 4A of the backing plate 4 are, for example, perpendicular to each other. The printed circuit board 3 is, for example, in the form of a strip-shaped flat plate, and includes an opposite first plate surface (the left side in Fig. 4) and a second plate surface (the right side in Fig. 4). The printed circuit board 3 is disposed, for example, perpendicular to the bottom portion 4B of the back panel 4, and is movable between the side portion 4A of the back panel 4 and the first side surface 1A of the light guide panel 1. The distance between the printed circuit board 3 and the side portion 4A of the back sheet 4 is, for example, greater than or equal to the distance that the first board surface of the printed circuit board 3 is moved toward the side portion 4A due to thermal expansion of the light guide plate 1. .

In the backlight module provided in this embodiment, two support members 5 are disposed between the printed circuit board 3 and the first side 1A of the light guide plate 1 for supporting the printed circuit board 3 and the light guide plate 1 And the distance between the light emitting surface of the light source 2 and the first side surface 1A of the light guide plate 1 is not less than a set interval. This set pitch is, for example, the vertical height of the support member 5 between the printed circuit board 3 and the light guide plate 1. In the present embodiment, one end of each of the support members 5 is fixed to the second plate surface of the strip-shaped flat printed circuit board 3. Ends, and each support member 5 has a height higher than the height of any one of the light sources 2 in a direction perpendicular to the second board surface of the printed circuit board 3 to support the printed circuit board 3 and the light guide plate 1, and The distance between the light emitting surface of the light source 2 and the side surface of the light guide plate 1 is made not less than a set pitch, for example, such that the distance between the light emitting surface of the light source 2 and the side surface of the light guide plate 1 is kept at a fixed pitch.

The fixing means 5 and the printed circuit board 3 can be fixed by means of adhesive fixing or screw fixing. In one example, the support member 5 may be cylindrical, prismatic or square. The support member 5 can also be selected from other shapes according to the actual situation.

In the present embodiment, regardless of whether or not the light guide plate 1 is expanded, the distance between the light-emitting surface of the light source 2 and the side surface of the light guide plate 1 is maintained at not less than a set pitch due to the presence of the support member 5. In this way, it is possible to prevent the distance between the light-emitting surface of the light source 2 and the side surface of the light guide plate 1 from being too small to expand in the direction in which the light source 2 is expanded when the light guide plate 1 is expanded to cause the light source 2 to be broken, or to be too close to the light source 2. The light guide plate 1 itself is thermally deformed.

In order to ensure that the light-emitting surface of the light source 2 and the side of the light guide plate 1 can be maintained at a fixed distance, for example, regardless of whether the light guide plate is inflated, thereby ensuring that the pitch is uniform in design and practical application, each support member 5 The two ends of the support member 5 are respectively fixed on the printed circuit board 3 and the light guide plate 1. The light emitting surface of the light source 2 and the light guide plate 1 are respectively supported on the printed circuit board 3 and the light guide plate 1. The distance between the sides is the height of the support 5 minus the height of the light source 2 in the direction perpendicular to the side of the vertical portion of the printed circuit board 3.

In order to further ensure that the light guide plate maintains a fixed distance between the light emitting surface of the light source 2 and the side surface of the light guide plate 1 during the expansion process, in one example, the support member 5 adopts a low expansion coefficient and has a supporting ability. Made of material. For example, the support member 5 is made of aluminum and has a coefficient of expansion of 23 x ^{10 - 6} / ° C.

The first board surface of the printed circuit board 3 and the side portion 4A of the back board 4 have a spacing, for example, greater than or equal to the thermal expansion of the light guide plate 1 when the backlight module is in operation, such that the side surface 1A thereof faces the back board 4. The distance at which the side portion 4A is displaced.

In the backlight template provided in this embodiment, a retractable member may be further included, and both ends of the retractable member are respectively fixed on the printed circuit board 3 and the back board 4, that is, disposed on the first board surface of the printed circuit board 3. In a space with the side portion 4A of the backboard 4, the telescopic member is configured to contract and store energy when pressed by an external force, and to stretch and release energy when the external force is withdrawn, and at this time The distance is not limited to a distance greater than or equal to the displacement of the side surface 1A of the side plate 1A toward the side portion 4A of the back plate 4 due to thermal expansion of the light guide plate 1 during operation. The example of providing the telescopic member better ensures the spacing between the light source and the side of the light guide plate with respect to the example in which the telescopic member is not disposed within the above-described pitch, so that the structure of the backlight module is more reasonable. Examples of the telescopic member are springs (e.g., coil springs, leaf springs, etc.), foamed plastics, and the like. As shown in Figures 3 and 4, the telescopic member is, for example, a spring 6A.

In this embodiment, the retractable member is configured to be in a natural state or a micro-compressed state when the light guide plate 1 is not inflated; when the light guide plate 1 is inflated to expand outward and push the printing through the support member 5 The circuit board is such that the retractable member between the printed circuit board and the back plate is pressed to be in a contracted state, and the amount of contraction of the retractable member is determined by the amount of expansion of the light guide plate.

In order to ensure that whether the light guide plate 1 is inflated or not, a fixed distance between the light emitting surface of the light source 2 and the side surface of the light guide plate 1 can be maintained, thereby ensuring that the pitch is uniform in design and practical application, and one end of the support member 5 can be It is fixed to one of the printed circuit board 3 and the light guide plate 1, and the other end of the support member 5 is kept in contact with the other of the printed circuit board 3 and the light guide plate 1 under the action of the expandable member.

As shown in Figures 3-4, three of said springs 6A are employed. The three springs 6A are evenly arranged along the longitudinal direction of the printed circuit board 3. The expansion and contraction directions of the three springs 6A are, for example, perpendicular to the side faces of the light guide plate 1; each spring 6A-end is fixed to the inner side of the side portion 4A of the back plate 4, and the other end is fixed to the strip-shaped flat printed circuit board. The first plate of 3 is contracted when pressed by an external force, and stretched when the external force is withdrawn. The plurality of light sources 2 are disposed on a second plate surface of the strip-shaped flat printed circuit board 3 opposite to the first plate surface. The light emitting face of each light source 2 is, for example, parallel to the second plate face of the printed circuit board 3.

In the backlight module, the fixing manner of the spring 6A and the printed circuit board 3 may be fixed by means of adhesive fixing or screwing, and the fixing manner of the side portion 4A of the backing plate 4 may be adhesive fixing, screw fixing or card. Fixed. The snap-fit manner means, for example, that one end of the spring 6A is connected to one surface of the strip-shaped flat printed circuit board 3, and the other end is passed through a screw and a screw card card provided on the side portion 4A of the back plate 4. It is fitted inside the side portion 4A of the backboard 4.

The telescopic member can also employ a flexible mechanism. The flexible mechanism is a mechanism that utilizes the elastic deformation of the members themselves in the mechanism to complete the transmission and conversion of motion and force. It does not rely on the motion pair to achieve all the movements and functions like the rigid mechanism. It mainly relies on the deformation of the flexible members in the mechanism to realize the main movement and function of the mechanism. It can also realize the transmission and conversion of motion, force and energy. Soft The number of components is much lower than that of traditional rigid mechanisms. The most direct effect is to greatly reduce the weight of the mechanism and the time and cost of processing and installation. Flexible mechanism structure, easy to manufacture, frictionless wear, easy assembly, high precision and high reliability, light weight and miniaturization have been widely used in mechanical applications.

The material of the flexible mechanism can be selected according to the size of each relevant component in the backlight module and the required elastic modulus. In one example, the flexible mechanism is made of at least one of beryllium bronze, titanium bronze, aluminum alloy, spring steel, and polypropylene. The elastic modulus E of the above materials is shown in Table 1:

Table 1

As shown in Figure 5-7, the telescopic member can adopt a U-shaped flexible mechanism 6B1 and an S-type flexible mechanism.

6B2, at least one of the left and right symmetrical flexible mechanisms 6B3, or a combination of any two.

In one example, the support members may be at least two; the telescopic members may be at least two. Moreover, in order to be evenly stressed, the at least two support members and the at least two telescopic members are uniformly and longitudinally disposed in the longitudinal direction of the printed circuit board.

Second embodiment:

As shown in FIGS. 8 and 9, the second embodiment differs from the first embodiment in that: the printed circuit board 3 has an L-shaped plate shape including horizontal and vertical portions perpendicular to each other, and the vertical portion Arranged perpendicularly to the bottom 4B of the backing plate 4, the horizontal portion approaches or contacts the inside of the bottom portion 4B of the backing plate 4 and extends between the bottom surface of the light guiding plate 1 and the bottom portion 4B of the backing plate 4. The horizontal portion contacts the inner side of the bottom portion 4B of the backing plate 4 to facilitate heat dissipation.

One end of each spring 6A is fixed inside the side portion 4A of the back plate 4, and the other end is fixed to the outer side surface of the vertical portion of the L-shaped printed circuit board 3.

Each of the light sources 2 is disposed on the inner side surface of the vertical portion of the L-shaped printed circuit board 3, and the light emitting surface of each of the light sources 2 is parallel to the inner side surface of the vertical portion. The L-shaped printed circuit board 3 is more advantageous for heat dissipation than the strip-shaped printed circuit board 3 disposed perpendicularly to the bottom portion 4B of the backing plate 4 in the first embodiment. One end of each of the support members 5 is fixed to the inner side surface of the vertical portion of the L-shaped printed circuit board 3, and the height of each of the support members 5 in the direction perpendicular to the inner side of the vertical portion is larger than The height of any one of the light sources 2 is high to support the printed circuit board 3 and the light guide plate 1 such that the distance between the light emitting surface of the light source 2 and the side surface of the light guide plate is maintained at not less than a set interval, for example, when the support member 5 The other end is supported on the side surface 1A of the light guide plate 1 such that the distance between the light emitting surface of the light source 2 and the side surface of the light guide plate 1 is maintained at a fixed pitch, such as the support member 5 being perpendicular to the vertical portion of the printed circuit board 3. The height in the side direction is subtracted from the height of the light source 2.

Other structures and functions in this embodiment are the same as or similar to those of the second embodiment, and will not be described again.

Third embodiment:

As shown in FIGS. 10-12, the third embodiment differs from the second embodiment in that: one end of each support member 5 is fixed to the inner side surface of the horizontal portion of the L-shaped printed circuit board 3, and is perpendicular to In the direction of the first side surface of the light guide plate 1, at this time, when the light guide plate 1 is not inflated, the support member 5 is not in contact with the side surface of the vertical portion of the printed circuit board 3. The side of each of the support members 5 adjacent to the side of the light guide plate is closer to the side of the light guide plate than the light emitting surface of any one of the light sources 2 to support between the vertical portion of the printed circuit board 3 and the light guide plate 1 so that the light source The light emitting surface of the light guide plate 2 and the first side surface 1A of the light guide plate 1 are maintained at a not less than a set interval, for example, the distance between the light emitting surface of the light source 2 and the side surface of the light guide plate 1 is maintained at a fixed pitch. For example, the height of the support member 5 in the direction perpendicular to the side of the vertical portion of the printed circuit board 3.

Fourth embodiment:

As shown in Figs. 13-15, the fourth embodiment differs from the first embodiment in that the strip-shaped flat printed circuit board 3 is disposed in parallel with the bottom portion 4B of the back plate 4. One end of each spring 6A is fixed inside the side portion 4A of the back plate 4, and the other end is fixed to one side of the strip-shaped flat printed circuit board 3.

Each of the light sources 2 is disposed on a plate surface of the strip-shaped flat printed circuit board 3 away from the bottom portion 4B of the back plate, and the light-emitting surface of each of the light sources 2 is perpendicular to the plate surface away from the bottom of the back plate 1.

One end of each of the support members 5 is fixed to the surface of the strip-shaped flat printed circuit board 3 away from the bottom plate 4B of the back plate, and in the direction perpendicular to the side of the light guide plate 1, each support member 5 is close to One side of the side surface of the light guide plate 1 is closer to the side surface of the light guide plate 1 than the light emitting surface of any one of the light sources 2 to support the printed circuit board 3 and the light guide plate 1 and to make the light emitting surface of the light source 2 and the light guide plate The spacing between the side faces is maintained at not less than a set spacing, for example such that the distance between the light emitting face of the light source 2 and the side of the light guide plate 1 is maintained at a fixed pitch. In this embodiment, the support member 5 may have a square shape.

The thickness of the strip-shaped flat printed circuit board in the embodiment and the strip-shaped flat printed circuit board in the first embodiment may be greater than the thickness of the L-shaped printed circuit board in the second and third embodiments. This is advantageous both for heat conduction and for the fixing of the telescopic member (for example, a spring) on one side of the strip-shaped flat printed circuit board.

Other structures and functions in this embodiment are the same as or similar to those of the first embodiment, and will not be described again.

Fifth embodiment:

As shown in FIGS. 16-18, the fifth embodiment differs from the fourth embodiment in that: the support member 5 has an L-shaped block shape, and the top end of one arm of each L-shaped block-shaped support member 5 is fixed in a strip shape. The flat printed circuit board 3 is away from the upper surface of the back plate 4, and the other arm is perpendicular to the first side of the light guide plate 1 and extends in a direction approaching the light guide plate 1. The L-shaped block-shaped support member 5 is advantageous for supporting the printed circuit board 3 and the light guide plate 1 as compared with the square-shaped support member 5 of the fifth embodiment, and saves material.

Other structures and functions in this embodiment are the same as or similar to those of the fourth embodiment, and will not be described again.

Embodiments of the present invention also provide a display device including any of the above backlight modules.

One example of the display device is a liquid crystal display device. The liquid crystal display device further includes a liquid crystal cell in which the TFT array substrate and the counter substrate are opposed to each other, and the liquid crystal cell is filled with a liquid crystal material. The opposite substrate is, for example, a color filter substrate. The pixel electrode of each pixel unit of the TFT array substrate is used to apply an electric field to control the degree of rotation of the liquid crystal material to perform a display operation.

According to the above description, an embodiment of the present invention can provide at least the following structure:

(1) A backlight module, comprising: a light guide plate having a bottom surface and a side surface; the back plate including at least a bottom portion disposed under the bottom surface of the light guide plate and the light emitting device, and a surface facing the light guide plate a side portion and a side portion spaced apart therefrom; a light emitting device including a light source and a printed circuit board electrically connected to the light source; and a support member configured to support the printed circuit board and the light guide plate Spacing.

(2) The backlight module of (1), wherein the printed circuit board is connected to a side of the backboard by a retractable member.

(3) The backlight module of (2), wherein the expandable member is configured such that the support member simultaneously contacts the side surface of the light guide plate and the printed circuit board.

The backlight module according to any one of (1) to (3), wherein the support member is fixed to the printed circuit board, and the support member is closest to the light guide plate One end of the side surface is closer to the side surface of the light guide plate than the light emitting surface of the light source; or the support member is simultaneously fixed to the printed circuit board and the light guide plate.

(5) The backlight module according to any one of (1) to (4), wherein

The backboard includes bottom and sides perpendicular to each other; the printed circuit board has a strip shape and is disposed perpendicular to a bottom of the backboard; the telescopic member is perpendicular to the side of the light guide panel, and one end Fixed on the inner side of the side of the backboard, the other end is fixed on the first board surface of the printed circuit board; the light source is disposed on the second board surface of the printed circuit board opposite to the first board surface, And the light emitting surface of the light source is parallel to the second board surface; one end of the support member is fixed on the second board surface of the printed circuit board, and the support member is in a direction perpendicular to the second board surface The height above is higher than the height of the light source.

(6) The backlight module according to any one of (1) to (4), wherein

The backboard includes bottom and sides perpendicular to each other; the printed circuit board has an L-shaped plate shape including horizontal and vertical portions perpendicular to each other, and the vertical portion is perpendicular to the bottom of the back plate The horizontal portion approaches or contacts the inner side of the bottom of the backboard and extends toward the side of the light guide plate; the extendable member is perpendicular to the side of the light guide plate, and one end is fixed to the side of the back plate The inner side is fixed on the outer side surface of the vertical portion of the L-shaped printed circuit board; the light source is disposed on the inner side surface of the vertical portion of the L-shaped printed circuit board, and the light emitting surface of the light source is The inner side faces of the vertical portions are parallel.

(7) The backlight module according to (6), wherein

One end of the support member is fixed to an inner side surface of the vertical portion of the L-shaped printed circuit board, and the height of the support member in a direction perpendicular to the inner side surface of the vertical portion is higher than the height of the light source.

(8) The backlight module according to (6), wherein One end of the support member is fixed on an inner side surface of a horizontal portion of the L-shaped printed circuit board, and the support member is closest to the side of the light guide plate in a direction perpendicular to the side surface of the light guide plate One end is closer to the side of the light guide plate than the light emitting surface of the light source.

The backlight module according to any one of (1) to (4), wherein

The backboard includes bottom and sides perpendicular to each other; the printed circuit board has a strip shape and is disposed in parallel with the bottom of the backboard; the telescopic member is perpendicular to the side of the light guide plate, and one end is fixed on the back The inner side of the side of the board is fixed on one side of the strip-shaped flat printed circuit board; the light source is disposed on the surface of the strip-shaped flat printed circuit board away from the bottom of the back board, and the light emitting surface of the light source is The plate surface away from the bottom of the back plate is perpendicular; one end of the support member is fixed on a plate surface of the strip-shaped flat printed circuit board away from the bottom of the back plate, and in a direction perpendicular to the side of the light guide plate, the support The side of the member close to the side of the light guide plate is closer to the side of the light guide plate than the light emitting surface of the light source.

(10) The backlight module of (9), wherein the support member has an L-shaped block shape, and an end of one arm of the L-shaped block-shaped support member is fixed on a strip-shaped flat printed circuit board away from the back plate On the bottom plate surface, the other arm is perpendicular to the side of the light guide plate and extends in a direction approaching the light guide plate.

The backlight module according to any one of (1) to (10), wherein the support member has a cylindrical shape, a prism shape, an L shape or a square shape.

The backlight module according to any one of (1) to (11), wherein the retractable member is a spring or a flexible mechanism.

The backlight module according to any one of (1) to (12), wherein the support member is at least two; and the telescopic member is at least two.

(14) A display device comprising the backlight module according to any one of claims (1) to (13).

Embodiments of the invention may have the following beneficial effects:

1) In the backlight module provided by the embodiment of the present invention, since there is a support member configured to support the printed circuit board and the light guide plate, it is ensured that the distance between the light emitting surface of the light source and the first side surface of the light guide plate is maintained as Not less than a set pitch. In this way, it is possible to prevent the light source from damaging the light source when it is inflated, or to approach the light source so that the light guide plate itself is thermally deformed to maintain a fixed pitch, and also prevent the light emitting surface of the light source from directly contacting the side of the light guide plate. In addition, the spacing between the printed circuit board and the side of the backplane may be set to be greater than or equal to the displacement of the first side of the backlight panel toward the side of the backplane due to the thermal expansion of the light guide panel during operation of the backlight module. The distance, thereby better achieving the above technical effects. 2) In the backlight module provided by the embodiment of the present application, when the spacing between the light emitting surface of the light source and the first side of the light guide plate is maintained at a fixed interval, the spacing is not caused by whether the light guide plate is expanded. (expanded due to the influence of the light source and the ambient temperature and humidity), it can prevent the light guide plate from expanding toward the light source when it expands to prevent the light source from being broken, or too close to the light source to cause the light guide plate itself to be thermally deformed, and when the pitch is set properly It can also improve the Hotspot phenomenon. Therefore, the backlight module provided by the embodiment of the invention avoids the light source energy utilization of the light source, reduces the light loss, and improves the backlight in order to prevent the light guide plate from expanding and preventing the light source from expanding. The picture quality of the display device to which the module is applied.

3) In the backlight module provided by the embodiment of the present invention, the retractable member can absorb the thrust which is outwardly expanded when the light guide plate expands and acts on the printed circuit board, and shrinks, and the deformation of the light guide plate is restored and the pin is applied to the printing. The thrust on the circuit board is extended, that is, the telescopic member can be fixed according to the pitch of the light guide plate.

4) The backlight module provided by the embodiment of the present invention is more suitable for application in a large-sized display device.

5) The manufacturing process and structure of the backlight module provided by the embodiments of the present invention have high reliability and feasibility.

Although the present invention has been described in detail above with the aid of the general description and specific embodiments, the invention is not limited thereto. It will be apparent to those skilled in the art that modifications, additions or deletions may be made thereto based on the present invention. Therefore, such modifications or improvements made without departing from the spirit of the invention are intended to be within the scope of the invention.

Claims

Claim

A backlight module comprising:

a light guide plate having a bottom surface and a side surface;

The back plate includes at least a bottom portion disposed under the bottom surface of the light guide plate and the light emitting device, and a side portion facing the side surface of the light guide plate and spaced apart therefrom;

a light emitting device comprising a light source and a printed circuit board electrically connected to the light source, and

And a support member configured to support the printed circuit board and the light guide plate such that a distance between a light emitting surface of the light source and the side surface of the light guide plate is greater than or equal to a set pitch.

The backlight module according to claim 1, wherein the printed circuit board is connected to a side of the backboard by a stretchable member.

The backlight module according to claim 2, wherein the retractable member is configured such that the support member simultaneously contacts the side surface of the light guide plate and the printed circuit board.

The backlight module according to any one of claims 1 to 3, wherein the support member is fixed on the printed circuit board, and the side of the support member closest to the side of the light guide plate One end is closer to the side surface of the light guide plate than the light emitting surface of the light source; or the support member is simultaneously fixed to the printed circuit board and the light guide plate.

The backlight module according to any one of claims 1 to 4, wherein

The backboard includes bottom and sides perpendicular to each other; the printed circuit board has an L-shaped plate shape including horizontal and vertical portions perpendicular to each other, and the vertical portion is perpendicular to the bottom of the back plate The horizontal portion approaches or contacts the inner side of the bottom of the backboard and extends toward the side of the light guide plate; the extendable member is perpendicular to the side of the light guide plate, and one end is fixed to the side of the back plate Inside, The other end is fixed on the outer side surface of the vertical portion of the L-shaped printed circuit board; the light source is disposed on the inner side surface of the vertical portion of the L-shaped printed circuit board, and the light emitting surface of the light source and the vertical The inner side of the part is parallel.

7. The backlight module according to claim 6, wherein

8. The backlight module according to claim 6, wherein

One end of the support member is fixed on an inner side surface of a horizontal portion of the L-shaped printed circuit board, and the support member is closest to the side of the light guide plate in a direction perpendicular to the side surface of the light guide plate One end is closer to the side of the light guide plate than the light emitting surface of the light source.

The backlight module according to any one of claims 1 to 4, wherein

The backlight module according to claim 9, wherein the support member has an L-shaped block shape, and a top end of one arm of the L-shaped block-shaped support member is fixed on a strip-shaped flat printed circuit board away from the bottom of the back plate The other arm is perpendicular to the side of the light guide plate and extends toward the light guide plate.

The backlight module according to any one of claims 1 to 10, wherein the support member has a cylindrical shape, a prism shape, an L shape or a square shape.

The backlight module according to any one of claims 1 to 11, wherein the telescopic member is a spring or a flexible mechanism.

The backlight module according to any one of claims 1 to 12, wherein at least two of the support members are used; and at least two of the extendable members are used.

A display device comprising the backlight module of any one of claims 1-13.