CN116819673A - Backlight module and display device that can maintain the folding design angle of the reflective sheet - Google Patents

Abstract

The invention provides a backlight module and a display device that can maintain the folding design angle of the reflective sheet. The backlight module includes: a backplane having at least one side wall; a light guide plate disposed in the backplane and the light guide plate and the backplane There is a reserved space between the side walls; and a reflective sheet, which is arranged between the back plate and the light guide plate. The reflective sheet includes a substrate part, an extension part and a support part. The substrate part is located between the back plate and the light guide plate. The extension part The supporting part is located in the reserved space, and at least a part of the supporting part is against the side wall of the back panel.

Description

Backlight module and display device that can maintain the folding design angle of the reflective sheet

Technical field

The present invention generally relates to a backlight module, and more specifically, to a backlight module having a multi-folded reflective sheet and a display device using the backlight module.

Background technique

Display panels and panel display devices using display panels have gradually become the mainstream of various display devices. For example, various panel display screens, household flat-screen TVs, flat-panel monitors for personal computers and laptop computers, display screens for mobile phones and digital cameras, etc., are all products that use a large number of display panels. In particular, the market demand for liquid crystal display devices has grown significantly in recent years. In order to meet the functional and appearance requirements of liquid crystal display devices, the designs of backlight modules used in liquid crystal display devices have become increasingly diversified.

Common backlight modules on the market can usually be divided into side-type and direct-type according to the difference in the incident position of the light source, so as to provide a uniform surface light source for the liquid crystal display module installed on it. Edge-type backlight modules usually include components such as a backplane, a light guide plate, a reflective sheet, and a plastic frame. The light guide plate is placed in the accommodation space on the backplane, and between the sides of the light guide plate and the side walls of the backplane There is usually room left to accommodate other components or to provide thermal expansion margin during subsequent reliability testing.

As the name suggests, the edge-type backlight module has a light source (such as an LED chip or a cold cathode fluorescent lamp CCFL) that is incident from the side of the light guide plate, and uses the light guide plate and reflective sheet to convert the side light source into a direction facing the liquid crystal display module. Set of area lights. The reflective sheet can be designed to have an integrally formed folding portion, which extends into the reserved space between the side wall of the back plate and the side of the light guide plate to reflect the light emitted from the side of the light guide plate. , to enhance the brightness of the luminous surface. However, the disadvantage of such a reflective sheet design is that the folded edge portion of the reflective sheet extends into the reserved space between the light guide plate and the back plate, but is tilted toward the side wall of the back plate and cannot be close to the side of the light guide plate, so it is difficult to maintain. The preset reflection angle causes problems such as uneven reflected light or bright lines near the edge of the light-emitting surface of the light guide plate.

Contents of the invention

In view of the shortcomings of the above-mentioned conventional methods, the present invention proposes a novel backlight module structure, which is characterized in that at least two fold lines are provided on the edge of the reflective sheet of the backlight module, in conjunction with the limiters on the side walls of the back panel. The design can maintain the preset reflection angle of the reflective sheet to achieve better optical taste.

One aspect of the present invention is to propose a backlight module, which includes a backplane with at least one side wall; a light guide plate that is disposed in the backplane, and there is a predetermined space between the light guide plate and the side wall of the backplane. leaving space; and a reflective sheet, which is disposed between the back plate and the light guide plate, the reflective sheet includes a substrate part, an extension part and a support part, the substrate part is located between the back plate and the light guide plate, the extension part And the support part is located in the reserved space, and at least a part of the support part is against the side wall of the back panel.

Another aspect of the present invention is to provide a display device, which includes the above-mentioned backlight module and a display panel disposed above the backlight module.

These and other objects of the present invention will become more apparent after the reader reads the following detailed description of the preferred embodiments, which are illustrated in various illustrations and accompanying drawings.

Description of the drawings

The accompanying drawings constitute a part of this specification and enable readers to further understand the embodiments of the present invention. The drawings depict some embodiments of the invention and, together with the description herein, explain the principles thereof. In these drawings:

Figure 1 is a schematic cross-sectional view of a backlight module according to an embodiment of the present invention;

Figure 2 is a schematic cross-sectional view of a backlight module according to another embodiment of the present invention; and

FIG. 3 is a schematic cross-sectional view of a backlight module according to another embodiment of the present invention.

It should be noted that all drawings in this specification are illustrations in nature. For the sake of clarity and convenience, the size and proportion of the components in the drawings may be exaggerated or reduced. Generally speaking, the parts in the drawings are the same. Symbols are used to identify corresponding or similar component features in modified or different embodiments.

Detailed ways

Exemplary embodiments of the present invention will now be described in detail, with reference to the accompanying drawings in which the described features will be understood by the reader to achieve the technical effects. Readers will understand that the description herein is by way of illustration only and is not intended to limit the case. The various embodiments and various features of the embodiments that do not conflict with each other can be combined or rearranged in various ways. Without departing from the spirit and scope of the present invention, modifications, equivalents, or improvements to the present invention will be understandable to those skilled in the art, and are intended to be included within the scope of the present invention.

Readers should be able to easily understand that the meanings of "on", "over" and "over" in this case should be interpreted in a broad way, so that "on" not only means "directly on" "Something "on", but also includes the meaning of being "on" something with intermediary features or layers in between, and "on..." or "over..." not only means "on" something "on" or "above", but may also include the meaning of being "on" or "above" something without intervening features or layers (i.e., directly on something).

In addition, spatially related terms such as “under”, “below”, “lower”, “above”, “upper” and other spatially related terms may be used herein to describe the relationship between one element or feature and another for convenience of description. The relationship of one or more elements or features as illustrated in the drawings.

Readers can usually understand a term, at least in part, from its context. For example, the term "one or more" as used herein may be used in the singular to describe any feature, structure or characteristic, or may be used in the plural to describe a combination of features, structures or characteristics, depending at least in part on context. Similarly, terms such as "a," "an," "the," or "the" may equally be understood to convey a singular usage or to convey a plural usage, depending at least in part on the context. Additionally, the term "based on" may be understood as not necessarily intended to convey an exclusive set of factors, but may allow for the presence of additional factors that are not necessarily explicitly described, again depending at least in part on the context.

Readers can better understand that when the words "comprising" and/or "containing" are used in this specification, they limit the existence of the stated features, regions, wholes, steps, operations, elements and/or components, but It does not exclude the possibility of the presence or addition of one or more other features, regions, integers, steps, operations, elements, parts and/or combinations thereof.

Please refer now to FIG. 1 , which is a schematic cross-sectional view of a backlight module according to an embodiment of the present invention. As shown in FIG. 1 , the backlight module proposed by the present invention generally includes a backplane 1 , a light guide plate 2 and a reflective sheet 3 . The back plate 1 can be a plate made of rigid materials such as metal, which has predetermined mechanical strength and supporting force. The light guide plate 2 can be a plate structure made of a polymer transparent material, which can guide the side-incident light source to the light exit surface of the light guide plate through the principle of total reflection. The reflective sheet 3 can be a white reflective film, which has high reflectivity and low transmittance, and can reflect the light from the bottom or side of the light guide plate 2 back into the light guide plate 2 . In the embodiment of the present invention, the edge of the reflective sheet 3 can be concavely folded along the fold line to reflect lateral light leakage. The concave folding method will be described in detail later.

In terms of positional relationship, the light guide plate 2 is arranged in the accommodation space on the back plate 1 and is surrounded by the side walls 12 of the back plate 1 (Figure 1 only shows one of the side walls 12 and a part of the light guide plate 2) , and there is a reserved space D between the light guide plate 2 and the side wall 12 . It should be noted that in an actual backlight module, other optical films may be provided on the light exit surface of the light guide plate 2, such as diffusion sheets, color conversion sheets, prism sheets and other components. In addition, the back panel 1 can also be combined with a plastic frame. Since the above-mentioned components are not the focus of the present invention, these components will not be shown in the drawings of the present invention for the purpose of concise illustration and to avoid obscuring the focus of the present invention.

One of the features of the present invention is that the edge of the reflective sheet 3 has more than two fold lines. Taking two fold lines as an example, as shown in Figure 1, the reflective sheet 3 includes a substrate portion 31, an extension portion 32 and a support portion 33. The first fold line L1 is located between the substrate portion 31 and the extension portion 32, and the second fold line L1 is located between the substrate portion 31 and the extension portion 32. L2 is located between the extension part 32 and the support part 33 . The substrate portion 31 is the main body of the reflective sheet 3 and is located between the back surface of the light guide plate 2 and the bottom 11 of the back plate 1 . One end of the extension portion 32 is connected to the substrate portion 31 , and the other end extends into the reserved space D. One end of the support portion 33 is connected to the extension portion 32 , and the other end (or at least a part thereof) is against the side wall 12 of the back panel 1 . More specifically, in the embodiment of the present invention, the reflective sheet 3 is preferably made of elastic material, and more preferably, the reflective sheet 3 is designed to be integrally formed. More specifically, the substrate portion 31 and the extension portion 32 of the reflection sheet 3 can be bent to form any angle, and the extension portion 32 and the support portion 33 can also be bent to form any angle. The elasticity of the reflection sheet 3 is used to extend the reflection sheet 3 . There is a supporting force between the part 32 and the supporting part 33. In this way, the extension section 32 can be brought as close as possible to the side of the light guide plate 2 to maintain the preset reflection angle of the reflective sheet 3 relative to the light guide plate 2, thus having the ability to improve the light guide plate 2. The effect of light uniformity of light plate 2. In addition, the positions of the first fold line and the second fold line of the reflective sheet 3 are also flexibly compatible and suitable for designs with different backlight module sizes or reserved space D sizes.

In one embodiment, the extension portion 32 has a first surface 32a facing the light guide plate 2 and a second surface 32b facing the back plate 1, and the substrate portion 31 has a first angle θ ₁ relative to the first surface 32a of the extension portion 32, The support part 33 has a second angle θ ₂ relative to the second surface 32 b of the extension part 32 , and the first angle θ ₁ is preferably greater than the second angle θ ₂ . In an actual arrangement, the extension part 32 and the support part 33 located in the reserved space D can be elastically bent to any first angle θ ₁ and second angle θ ₂ , and by pressing one end of the support part 33 against on the side wall 12 of the back panel 1 to achieve the effect of limiting and fixing. In another embodiment, pressing lines, rice lines or stitching lines can be made along the first folding line L1 or the second folding line L2, so that the base portion 31 and the extension portion 32 can be accurately folded later. The first fold line L1 between them and the second fold line L2 between the extension part 32 and the support part 33 . More specifically, the first fold line L1 is a valley fold line, and the second fold line L2 is a mountain fold line, so that the substrate portion 31 of the reflective sheet 3 is covered by the light guide plate 2, and the extension portion 32 and the support portion 33 extend into Reserve a space D so that the elasticity of the reflective sheet 3 can be used to push the other end of the support portion 33 against the side wall 12 to provide support for the extension portion 32 . In this way, the extension portion 32 can be as close as possible to the side of the light guide plate 2 , to maintain the preset reflection angle of the reflective sheet 3 relative to the light guide plate 2 to achieve better optical taste.

In order to achieve the best effect of reflecting light from the light guide plate 2 , the first angle θ ₁ is preferably adapted to the angle between the bottom surface and the side surface of the light guide plate 2 , for example, 90 degrees. However, in an actual arrangement, the elasticity of the reflective sheet 3 maintains the support force between the extension part 32 and the support part 33 . Usually, the first angle θ ₁ will be larger than the second angle θ ₂ and larger than 90 degrees. In this way, the elasticity of the reflective sheet 3 is used to make the other end of the support part 33 press against the side wall 12 to provide support for the extended part 32 . The extended part 32 of the reflective sheet 3 can be fixed and maintained at the optimal preset angle for reflecting light. , as in the conventional technology, the effect of reflecting light will not be reduced due to the tendency to tilt toward the side wall of the back panel 1 and change the reflection angle.

In addition, the height of the connection between the extension part 32 and the support part 33 in the reflective sheet 3 is preferably the same as the height of the top surface of the light guide plate 2 to ensure that the light leakage from the side of the light guide plate can be reflected back into the light guide plate. Maintain the brightness of the backlight module.

In the present invention, additional limiting members or features may be formed on the side walls 12 of the back panel 1 to help maintain the position of the support portion 33 of the reflective sheet 3 relative to the side walls 12 . For example, as shown in FIG. 1 , a convex portion 121 is formed on the side wall 12 of the back plate 1 , which protrudes toward the direction of the light guide plate 2 and can contact the support portion 33 . During the installation process of the reflection sheet 3, by pressing one end of the support portion 33 against the side wall 12 of the back panel 1, the extension portion 32 and the support portion 33 of the reflection sheet 3 will naturally fold in the reserved space D. The reflective sheet 3 is fixed at a specific first angle θ ₁ and a second angle θ ₂ , and at least a part of the support portion 33 of the fixed reflective sheet 3 contacts and abuts the convex portion 121 . In addition, the height of the connection between the extending portion 32 of the reflective sheet 3 and the supporting portion 33 is preferably higher than the height of the position where the protruding portion 121 is located, so that the limiting effect of the protruding portion 121 can be better exerted. The advantage of this design is that with the help of the protrusions 121 on the side wall 12 , the attachment material between the side wall 12 and the reflective sheet 3 can be omitted.

Please refer now to FIG. 2 , which is a schematic cross-sectional view of a backlight module according to another embodiment of the present invention. As shown in FIG. 2 , the structure and components of the backlight module in this embodiment are substantially the same as those in the embodiment shown in FIG. 1 . The difference is that a recess 121 a is formed on the side wall 12 of the back plate 1 shown in FIG. 2 . In other words, whether it is the recessed portion 121a in this embodiment or the aforementioned convex portion 121, the step difference on the side wall 12 of the back plate 1 is used to make one end of the supporting portion 33 of the reflective sheet 3 abut against the recessed portion. 121a, and elastically and naturally adjusts its position in the reserved space D, finally achieving the effect of fixing the extension part 32 and the supporting part 33 of the reflective sheet 3. The advantages of this design are the same as those shown in the embodiment of Figure 1. With the help of the recessed portion 121a on the side wall 12, the attachment material between the side wall 12 and the reflective sheet 3 can also be omitted. Compared with the convex portion 121 of Figure 1 , the recess 121a of this embodiment can also ensure the space between the side wall 12 of the back plate 1 and the light guide plate 2, which is conducive to the convenience of installing other components.

Please refer now to FIG. 3 , which is a schematic cross-sectional view of a backlight module according to another embodiment of the present invention. As shown in FIG. 3 , the structure and components of the backlight module in this embodiment are substantially the same as those in the embodiment shown in FIG. 2 . The difference lies in the groove 121 b formed on the side wall 12 of the back plate 1 shown in FIG. 3 . In the embodiment, the end of the support portion 33 of the reflection sheet 3 can abut or be directly embedded in the groove 121 b to achieve the effect of fixing the extension portion 32 of the reflection sheet 3 and the support portion 33 . For example, the groove 121b is a plurality of holes or a whole channel on the surface of the side wall 12, and the end of the support part 33 can be embedded in the aforementioned groove 121b. In this way, not only the connection between the side wall 12 and the reflective sheet 3 can be omitted. The adhesive material between them can also ensure that the end of the reflective sheet 3 has a more stable limiting effect relative to the back plate 1 .

Based on the above embodiments, the present invention adopts the design of at least two or more fold lines provided on the edge of the reflective sheet of the backlight module, combined with the limiting features such as convex portions, concave portions or grooves formed on the side walls of the back panel. To achieve the effect of maintaining the preset reflection angle of the reflective sheet, it can be flexibly compatible with different backlight module sizes or reserved space sizes, and at the same time, the materials and related processes used to fix the folding edges of the reflective sheet can be reduced.

In addition to the foregoing embodiments, the present invention also provides a display device, which includes the backlight module described in any of the above embodiments, and a display panel disposed above the backlight module.

The above are only preferred embodiments of the present invention, and all equivalent changes and modifications made in accordance with the patentable scope of the present invention shall fall within the scope of the present invention.

[List of reference signs]

1 back panel

2 light guide plate

3 reflective sheets

11 bottom

12 side walls

31 substrate bottom

32 extension

32a first surface

32b second surface

33 support part

121 convex part

121a recess

121b groove

D reserved space

L1 first polyline

L2 second polyline

θ ₁ first angle

θ ₂ second angle.

Claims (10)

1. A backlight module that can maintain the folding design angle of the reflective sheet, including: a back panel having at least one side wall; A light guide plate, which is arranged in the back plate, with a reserved space between the light guide plate and the side walls of the back plate; and A reflective sheet is disposed between the back plate and the light guide plate. The reflective sheet includes a substrate portion, an extension portion and a support portion. The substrate portion is located between the back plate and the light guide plate. The extension part and the support part are located in the reserved space, and at least a part of the support part is against the side wall of the back panel. 2. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 1, wherein the extension portion has a first surface facing the light guide plate and a second surface facing the back plate, so The substrate portion has a first angle θ ₁ relative to the first surface of the extension portion, the support portion has a second angle θ ₂ relative to the second surface of the extension portion, and the first angle θ ₁ is greater than the Describe the second angle θ ₂ . 3. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 1, wherein the side wall of the back panel has a convex portion, and a part of the support portion abuts against the convex portion. Ministry. 4. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 3, wherein the height of the connection point between the extension part and the support part is higher than the height of the position of the convex part. 5. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 1, wherein the inner surface of the back plate has a groove, and the end of the extension portion abuts against the groove. on the trough. 6. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 5, wherein the height of the connection between the extension part and the support part is higher than the height of the groove. 7. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 1, wherein the height of the connection point between the extension part and the support part is the same as the height of the top surface of the light guide plate. 8. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 1, wherein there is a valley fold line between the substrate bottom and the extension part. 9. The backlight module capable of maintaining the folding design angle of the reflective sheet according to claim 1, wherein there is a mountain fold line between the extension part and the support part. 10. A display device, comprising: The backlight module capable of maintaining the folding design angle of the reflective sheet according to any one of claims 1 to 9; and A display panel is arranged above the backlight module.