TWM633304U - Light guide structure and backlight module using the same - Google Patents

Abstract

The present utility model discloses a light guide structure is used for a backlight module, the backlight module includes a light source, the light guide structure is used to guide a light emitted by the light source, and the light guide structure includes a plate body and a light shielding layer. The plate body includes a light-transmitting plate, a light-guiding plate and a reflective sheet sequentially stacked from top to bottom, and the light-guiding plate has side surfaces. The light-transmitting plate has a light-transmitting plate side surface, the reflection sheet has a reflection sheet side surface, and the side surface of the light guide plate, the light-transmitting plate side surface and the reflection sheet side surface constitute a plate body side surface. The light-shielding layer covers the plate body side surface, and the light-shielding layer is used to shield the light emitted by the light source from being emitted through the side surface of the light-guide plate.

Description

Light guide structure and backlight module with light guide structure

The invention relates to a backlight module with a light guide structure.

With the rapid development of science and technology, the vigorous development of electronic equipment has brought a lot of convenience to human life, so how to make the operation of electronic equipment more humanized is an important issue. For example, common electronic devices in daily life are notebook computers, mobile phones, satellite navigation devices, etc. Due to the dramatic increase in storage capacity and processor computing performance of these electronic devices, their functions are becoming increasingly powerful and complex. . In order to efficiently operate these electronic devices, manufacturers of electronic devices use a mouse, a trackball, a keyboard device, and a touch panel module as input devices to control the electronic devices.

Recently, with the improvement of consumers' visual demands, a light-emitting input device has become a new development direction of the industry. Generally speaking, a luminous keyboard device or a luminous touch panel module uses a backlight module as its light source. As shown in FIG. 13 and light source 14. The light-transmitting plate 11, the light guide plate 12, and the reflective sheet 13 are stacked sequentially from top to bottom. The light guide plate 12 has a light incident surface 121, a light exit surface 122, a bottom surface 123, and side surfaces 124. The light source 14 is disposed on the light incident surface of the light guide plate 12. 121 side. The light emitted by the light source 14 can enter the interior of the light guide plate 12 through the light incident surface 121 of the light guide plate 12 and be emitted from the light exit surface 122 of the light guide plate 12, so that the keyboard device or the touch panel can pass through the back surface. The light module 1 produces a luminous effect. However, the light entering the light guide plate 12 will also exit from the side 124 of the light guide plate 12 , so that the side 124 of the light guide plate 12 forms a bright spot and affects the appearance of the keyboard device or the touch panel. In view of this, in order to prevent the light emitted by the light source 14 from leaking from the side surface 124 of the light guide plate 12 , currently conventional backlight modules basically adopt the following two methods for the shading design.

In the shading design shown in Figure 2, the edges of the light-transmitting plate 11 and the edge of the reflective sheet 13 of the backlight module 1a are pressed, so that the edges of the light-transmitting plate 11 and the edge of the reflective sheet 13 are bent toward each other. , until the edge of the light-transmitting plate 11 and the edge of the reflective sheet 13 are attached to each other to form a wrapping region R, and the side surface 124 of the light guide plate 12 is wrapped between the light-transmitting plate 11 and the reflecting sheet 13 by this wrapping region R space, so as to prevent light from leaking from the side 124 of the light guide plate 12 . In the shading design shown in FIG. 3 , the side 124 of the light guide plate 12 of the backlight module 1 b is provided with a black light shielding layer (black mylar) 15 to prevent light from leaking from the side 124 of the light guide plate 12 .

However, in the light-shielding design shown in Figure 2, one of the light-transmitting plate 11 or the reflector 13 must be made of a soft material, so that the structural strength of the overall backlight module 1 is greatly reduced, and the light-transmitting plate 11 and the reflector 13 must be made of a soft material. 13 The length of edge bending must be greater than 3 cm, otherwise there will be a risk of cracking. Furthermore, in the light-shielding design shown in Figure 3, the black light-shielding layer 15 disposed on the side 124 of the light guide plate 12 must have a certain width, otherwise there is a risk of peeling off the black light-shielding layer 15, but if the width of the black light-shielding layer 15 If it is too long, the edge width of the backlight module 1 will increase and affect the appearance, and it will greatly increase the difficulty of assembling the backlight module 1 .

Therefore, how to improve the above problems is actually the focus of attention of relevant people in the field.

One of the purposes of the present invention is to provide a light guiding structure, which has the effect of preventing light leakage.

Another object of the present invention is to provide a backlight module whose light guiding structure has the effect of preventing light leakage.

Other purposes and advantages of this creation can be further understood from the technical characteristics disclosed in this creation.

In order to achieve one or part or all of the above purposes or other purposes, this invention provides a light guide structure for a backlight module, the backlight module includes a light source, the light guide structure is used to guide the light emitted by the light source, and the light guide structure Including board body and shading layer. The plate body includes a light-transmitting plate, a light guide plate and a reflective sheet stacked sequentially from top to bottom, and the light guide plate has side surfaces. The light-transmitting plate has a side of the light-transmitting plate, the reflection sheet has a side of the reflection sheet, and the side of the light guide plate, the side of the light-transmitting plate and the side of the reflection sheet constitute the side of the plate body. The light-shielding layer is covered on the side of the plate body, and the light-shielding layer is used to block the light emitted by the light source from exiting through the side of the light guide plate.

In an embodiment of the present invention, the above-mentioned light guide plate further has a light incident surface, a light exit surface and a bottom surface, the light exit surface is opposite to the bottom surface, the light incident surface is adjacent to the light exit surface, the bottom surface and the side surface, and the light source is arranged on the light entrance surface. One side, and the light emitted by the light source enters the light guide plate through the light incident surface and exits through the light exit surface.

In an embodiment of the present invention, the above-mentioned light-transmitting plate further has a top surface of the light-transmitting plate adjacent to the side of the light-transmitting plate. The bottom surface of the reflection sheet is opposite to the bottom surface of the light guide plate, and the light-shielding layer covers part of the top surface of the light-transmitting plate and part of the bottom surface of the reflection sheet.

In an embodiment of the present invention, the above-mentioned light-shielding layer includes a side wall layer, a top wall layer and a bottom wall layer, the top wall layer extends from one end of the side wall layer, and the bottom wall layer extends from the corresponding end of the side wall layer. Extending from the other end, the side wall layer covers the side of the plate body, the top wall layer covers part of the top surface of the light-transmitting plate, and the bottom wall layer covers part of the bottom surface of the reflective sheet.

In an embodiment of the present invention, the widths of the top wall layer and the bottom wall layer of the light-shielding layer are respectively greater than or equal to 0.1 mm and less than or equal to 0.25 mm.

In an embodiment of the present invention, the thicknesses of the side wall layer, the top wall layer and the bottom wall layer of the light-shielding layer are respectively greater than or equal to 6 microns and less than or equal to 12 microns.

In an embodiment of the present invention, the above-mentioned light-shielding layer is formed on the side surface of the board through an ink printing process or a painting process.

In an embodiment of the present invention, the above-mentioned light-shielding layer is a light-curable ink layer or a heat-curable ink layer.

This invention also proposes a backlight module, including a light source and a light guide structure. A light source is used to emit light. The light guide structure is used for guiding light, and the light guide structure includes a plate body and a light shielding layer. The plate body includes a light-transmitting plate, a light guide plate and a reflective sheet stacked sequentially from top to bottom. The light guide plate has a side surface, the light transmission plate has a light transmission plate side surface, and the reflection sheet has a reflection sheet side surface. The light-shielding layer is covered on the side of the plate body, and the light-shielding layer is used to block the light emitted by the light source from exiting through the side of the light guide plate.

The backlight module of this creative embodiment forms a light-shielding layer on the plate body of the light guide structure, and the light-shielding layer covers the side surface of the plate body, part of the top surface of the light-transmitting plate, and part of the bottom surface of the reflective sheet at the same time. Under such a structural design, In addition to effectively preventing light from leaking from the side of the light guide plate, the structural strength of the light guide structure can be further increased to prevent the light shielding layer from peeling off from the plate body. In addition, in the manufacturing method of the light guide structure in the embodiment of the invention, the light-transmitting plate, the light guide plate, and the reflective sheet are first assembled together to form a composite plate before performing other steps. Efficiency is greatly improved. Furthermore, through the original The light-guiding structure manufacturing method of the embodiment can effectively control the width of the light-shielding layer between 0.1 mm and 0.25 mm and the thickness of the light-shielding layer between 6 microns and 12 microns, so when the backlight of this embodiment After the module is disposed on the electronic equipment, the light-shielding layer of the light guide structure will not affect the appearance of the electronic equipment. In terms of product application, the backlight module of the present invention can be applied to keyboard devices, touch panels, various components of notebook computers or various forms of smart home appliances that require lighting.

In order to make the above and other purposes, features and advantages of this invention more comprehensible, preferred embodiments are specifically cited below, together with the accompanying drawings, and described in detail as follows.

1, 1a, 1b, 2: backlight module

11. 2211: transparent board

12. 2212: light guide plate

13. 2213: reflector

14, 21: light source

15: Black shading layer

121, 22122: incident surface

122, 22123: Light-emitting surface

123, 22124: bottom surface

124, 22121: side

22: Light guide structure

220: composite sheet

221: board body

222: shading layer

211: flexible circuit board

212: Light emitting element

2221: side wall layer

2222: top wall layer

2223: Bottom wall layer

22111: The side of the transparent plate

22112: Top surface of transparent board

22131: Reflector side

22132: The bottom surface of the reflector

G: Gap

PS: The side of the board

R: Hemming area

R1: Shading layer formation area

T: Thickness

W: width

FIG. 1 is a schematic cross-sectional view of a conventional backlight module.

FIG. 2 is a schematic cross-sectional view of a light-shielding design structure of the backlight module shown in FIG. 1 .

FIG. 3 is a schematic cross-sectional view of another light-shielding design structure of the backlight module shown in FIG. 1 .

FIG. 4 is a schematic cross-sectional view of a backlight module according to an embodiment of the present invention.

FIG. 5 is a schematic perspective view of the light guide structure shown in FIG. 4 .

FIG. 6A to FIG. 6E are schematic flowcharts of a manufacturing method of a light guide structure according to an embodiment of the present invention.

Please refer to FIG. 4 and FIG. 5 . FIG. 4 is a schematic cross-sectional view of a backlight module according to an embodiment of the present invention. FIG. 5 is a schematic perspective view of the light guide structure shown in FIG. 4 .

As shown in FIG. 4 and FIG. 5 , the backlight module 2 of this embodiment includes a light source 21 and a light guide structure 22 . The light source 21 is used for emitting light to the light guide structure 22 . The light guide structure 22 is used for guiding the light emitted by the light source 21 , and the light guide structure 22 includes a plate body 221 and a light shielding layer 222 . exist In this embodiment, the plate body 221 includes a transparent plate 2211 , a light guide plate 2212 and a reflective plate 2213 stacked sequentially from top to bottom. The light guide plate 2212 has a side surface 22121 . The transparent plate 2211 has a side surface 22111 of the transparent plate. The reflective sheet 2213 has a reflective sheet side 22131 . The side 22121 of the light guide plate 2212, the side 22111 of the light-transmitting plate and the side 22131 of the reflective sheet constitute the side PS of the plate body. The light-shielding layer 222 covers the side PS of the board body, that is, the light-shielding layer 222 covers the side 22121 of the light guide plate 2212 , the side 22111 of the light-transmitting plate and the side 22131 of the reflective sheet at the same time. The light shielding layer 222 is used for shielding the light emitted by the light source 21 from exiting through the side surface 22121 of the light guide plate 2212 .

It should be noted that, in this embodiment, the light-shielding layer 222 is, for example, a light-curable ink layer or a heat-curable ink layer, that is to say, the light-shielding layer 222 is in a flowable state when it is uncured, but this invention does not The material type of the light-shielding layer 222 is not limited. In addition, the light-shielding layer 222 is formed on the side PS of the plate body, for example, through an ink printing process or a paint spraying process, but the present invention is not limited thereto.

Further description will be given below for other detailed structures of the light guide structure 22 of the present invention.

As shown in FIG. 4 and FIG. 5 , the light guide plate 2212 of this embodiment further has a light incident surface 22122 , a light exit surface 22123 and a bottom surface 22124 . The light emitting surface 22123 of the light guide plate 2212 is opposite to the bottom surface 22124 , and the light incident surface 22122 is adjacent to the light emitting surface 22123 , the bottom surface 22124 and the side surface 22121 . In this embodiment, the light source 21 includes a flexible circuit board 211 and at least one light emitting element 212 disposed on the flexible circuit board 211, the light emitting element 212 is disposed on one side of the light incident surface 22122, and the light emitted by the light emitting element 212 passes through The light incident surface 22122 of the light guide plate 2212 enters into the light guide plate 2212 and exits through the light exit surface 22123 .

It should be noted that, as shown in FIG. 5 , in this embodiment, the appearance configuration of the light guide structure 22 is, for example, a rectangle. Therefore, the side 22121 of the light guide plate 2212 is other sides except the light incident surface 22122 . That is, the side 22121 of the light guide plate 2212 presents a U-shape Around the side, similarly, the side 22111 of the light-transmitting plate and the side 22131 of the reflective sheet also present a U-shaped surrounding side, that is, a plate composed of the side 22121 of the light guide plate 2212, the side 22111 of the light-transmitting plate and the side 22131 of the reflecting sheet The body side PS also presents a U-shaped surrounding side, and the light-shielding layer 222 also presents a U-shaped outer frame structure after covering the board body side PS.

As shown in FIG. 4 and FIG. 5 , the light-transmitting plate 2211 of this embodiment further has a top surface 22112 of the light-transmitting plate adjacent to the side surface 22111 of the light-transmitting plate, and the top surface 22112 of the light-transmitting plate is opposite to the light-emitting surface 22123 of the light guide plate 2212 . The reflection sheet 2213 further has a bottom surface 22132 of the reflection sheet adjacent to the side surface 22131 of the reflection sheet, and the bottom surface 22132 of the reflection sheet is opposite to the bottom surface 22124 of the light guide plate 2212 . In this embodiment, the light-shielding layer 222 covers part of the top surface 22112 of the light-transmitting plate and some The bottom surface of the reflector 22132. Under such a structural design, since the light-shielding layer 222 simultaneously covers the side PS of the plate body, part of the top surface 22112 of the light-transmitting plate, and part of the bottom surface 22132 of the reflective sheet, the light-guiding structure 22 of this embodiment can effectively prevent light from In addition to leakage from the side 22121 of the light board 2212 , the strength of the overall structure can be further increased to prevent the light shielding layer 222 from peeling off from the board body 221 .

It should be noted that the light-shielding layer 222 covering the side PS of the plate body, the top surface 22112 of the light-transmitting plate and the bottom surface 22132 of part of the reflective sheet in this embodiment is only one of the embodiments of this creation, and this creation is not limited thereto. In other embodiments, the light shielding layer 222 may also only cover the side PS of the board body.

As shown in FIG. 4 and FIG. 5 , the light shielding layer 222 of this example includes a side wall layer 2221 , a top wall layer 2222 and a bottom wall layer 2223 . The top wall layer 2222 of the light shielding layer 222 extends from one end of the side wall layer 2221 toward the board body 221 , and the bottom wall layer 2223 extends from the opposite end of the side wall layer 2221 toward the board body 221 . In this embodiment, the light shielding layer 222 The side wall layer 2221 of the light guide plate 2212 covers the side PS of the plate body formed by the side 22121 of the light guide plate 2212, the side 22111 of the light-transmitting plate, and the side 22131 of the reflector, while the top wall layer 2222 covers part of the top surface 22112 of the light-transmitting plate, and the bottom wall layer 2223 covers part of the bottom surface 22132 of the reflection sheet.

It is worth mentioning that, in this embodiment, the widths W of the top wall layer 2222 and the bottom wall layer 2223 of the light shielding layer 222 are respectively greater than or equal to 0.1 mm and less than or equal to 0.25 mm. The thickness T of the side wall layer 2221 , the top wall layer 2222 and the bottom wall layer 2223 of the light shielding layer 222 is greater than or equal to 6 microns and less than or equal to 12 microns.

Please refer to FIG. 6A to FIG. 6E , which are schematic flowcharts of a manufacturing method of a light guide structure according to an embodiment of the present invention. As shown in Figure 6A to Figure 6E, and please refer to Figure 4 and Figure 5 at the same time, the manufacturing method of the light guide structure 22 of this embodiment includes the following steps: first, as shown in Figure 6A, a composite plate 220 is provided, the composite The board 220 includes a light-transmitting plate 2211, a light-guiding plate 2212, and a reflective sheet 2213 stacked in sequence from top to bottom, that is, the independent light-transmitting plate 2211, light-guiding plate 2212, and reflecting sheet 2213 are assembled before proceeding to the next step. The above-mentioned composite plate 220 is formed on each other.

Then, as shown in FIG. 6B, the composite sheet 220 is cut so that the composite sheet 220 forms at least two panels 221, and each panel 221 has a panel side PS, and there is a gap G between these panel sides PS. The side PS of the plate body is composed of the side 22121 of the light guide plate 2212 , the side 22111 of the light-transmitting plate 2211 , and the side 22131 of the reflective plate 2213 .

Then, as shown in FIG. 6C , a light-shielding layer forming region R1 is defined between these boards 221 . The light-shielding layer forming region R1 covers the gap G between the sides PS of the plates, part of the top surface 22112 of the transparent plate, and part of the bottom surface 22132 of the reflective plate.

Then, as shown in FIG. 6D , the light-shielding layer 222 is formed in the light-shielding layer forming region R1 by means of an ink printing process or a painting process. Since the light shielding layer 222 is not cured The light-shielding layer 222 flows through the top surface 22112 of the light-transmitting plate, the side PS of the plate body, and the bottom surface 22132 of the reflective sheet from top to bottom in the light-shielding layer forming region R1 until the light-shielding layer 222 completely covers them. Part of the light-transmitting plate top surface 22112 of the plate body 221 , the side surface PS of the plate body and the bottom surface 22132 of a part of the reflective sheet. After the light-shielding layer 222 is cured, the two boards 221 are connected to each other through the cured light-shielding layer 222 .

Next, as shown in FIG. 6E , the light-shielding layer 222 between the boards 221 is cut so that the boards 221 are separated from each other, and the side PS of each board 221 has a part of the light-shielding layer 222 .

It should be noted that if the light-shielding layer 222 only needs to be formed on the side PS of these plates 221 and not on part of the top surface 22112 of the light-transmitting plate and part of the bottom surface 22132 of the reflective sheet, in the above step of FIG. 6C Among them, the light-shielding layer forming region R1 defined between the boards 221 only covers the gap G between the side faces PS of the boards. In addition, in this embodiment, if the light-shielding layer 222 is formed by an ink printing process, the light-shielding layer forming region R1 is defined through a black printing screen, and if the light-shielding layer 222 is formed by a paint spraying process , the light-shielding layer forming region R1 is defined through the spray-shielding jig.

It should be noted that, in order to clearly express the manufacturing method of the light guide structure in this embodiment, in this embodiment, only two plates 221 are cut out of the composite plate 220 for illustration. In fact, the composite plate 220 can be Simultaneously cutting out a plurality of boards 221 arranged in an array, and then simultaneously forming a light-shielding layer 222 on the boards arranged in an array through the above manufacturing process steps.

It is worth mentioning that the light guide structure completed through the above manufacturing process can be designed with perforated light barriers to meet the needs of partitioned lighting.

To sum up, the backlight module of the embodiment of the present invention forms a light-shielding layer on the plate body of the light guide structure, and the light-shielding layer covers the side surface of the plate body, part of the top surface of the light-transmitting plate, and part of the bottom surface of the reflective sheet at the same time. Under the structural design, in addition to effectively preventing light from leaking from the side of the light guide plate, the structural strength of the light guide structure can also be increased to prevent the light shielding layer from peeling off from the plate body. In addition, in the manufacturing method of the light guide structure in the embodiment of the invention, the light-transmitting plate, the light guide plate, and the reflective sheet are first assembled together to form a composite plate before performing other steps. Efficiency is greatly improved. Furthermore, through the manufacturing method of the light guide structure of the present invention, the width of the light-shielding layer can be effectively controlled between 0.1 mm and 0.25 mm, and the thickness of the light-shielding layer can be controlled between 6 microns and 12 microns. After the backlight module of this embodiment is configured on the electronic device, the light-shielding layer of the light guide structure will not affect the appearance of the electronic device. In terms of product application, the backlight module of the present invention can be applied to keyboard devices, touch panels, various components of notebook computers or various forms of smart home appliances that require lighting.

However, the above is only a preferred embodiment of this creation, and should not limit the scope of implementation of this creation, that is, all simple equivalent changes and modifications made according to the patent scope of this creation and the content of the creation description, All still belong to the scope that this new patent covers. In addition, any embodiment or patent scope of this creation does not need to achieve all the purposes or advantages or characteristics disclosed in this creation. In addition, the abstract part and the title are only used to assist in the search of patent documents, and are not used to limit the scope of rights of this creation. In addition, terms such as "first" and "second" mentioned in this specification or the scope of the patent application are only used to name elements (elements) or to distinguish different embodiments or ranges, and are not used to limit the number of elements. upper or lower limit.

2: Backlight module

21: light source

22: Light guide structure

221: board body

222: shading layer

211: flexible circuit board

212: Light emitting element

2211: Translucent panel

2212: light guide plate

2213: reflector

2221: side wall layer

2222: top wall layer

2223: Bottom wall layer

22121: side

22122: light incident surface

22123: light surface

22124: Bottom

22111: The side of the transparent plate

22112: Top surface of transparent board

22131: Reflector side

22132: The bottom surface of the reflector

PS: The side of the board

T: Thickness

W: width

Claims (9)

A light guide structure for a backlight module, the backlight module includes a light source, the light guide structure is used to guide a light emitted by the light source, the light guide structure includes: A plate body, including a light-transmitting plate, a light-guiding plate and a reflective sheet stacked in sequence from top to bottom, the light-guiding plate has a side, the light-transmitting plate has a side of the light-transmitting plate, and the reflecting sheet has a reflective The side of the sheet, the side of the light guide plate, the side of the light-transmitting plate and the side of the reflective sheet form a side of the plate body; and A light-shielding layer covers the side surface of the plate body, and the light-shielding layer is used to block the light emitted by the light source from exiting through the side surface of the light guide plate. The light guide structure according to claim 1, wherein the light guide plate further has a light incident surface, a light exit surface and a bottom surface, the light exit surface is opposite to the bottom surface, and the light entrance surface is adjacent to the light exit surface, the bottom surface and the bottom surface Between the side surfaces, the light source is arranged on one side of the light incident surface, and the light emitted by the light source enters the light guide plate through the light incident surface and exits through the light exit surface. The light guide structure according to claim 2, wherein the light-transmitting plate further has a top surface of the light-transmitting plate adjacent to the side of the light-transmitting plate, and the top surface of the light-transmitting plate is opposite to the light-emitting surface of the light guiding plate, and the reflection The sheet further has a bottom surface of the reflection sheet adjacent to the side of the reflection sheet, the bottom surface of the reflection sheet is opposite to the bottom surface of the light guide plate, and the light-shielding layer covers part of the top surface of the transparent plate and part of the bottom surface of the reflection sheet. The light guiding structure according to claim 3, wherein the light-shielding layer includes a side wall layer, a top wall layer and a bottom wall layer, the top wall layer extends from one end of the side wall layer, and the bottom wall layer extends from the The opposite end of the side wall layer extends out, the side wall layer covers the side of the plate body, the top wall layer covers part of the top surface of the light-transmitting plate, and the bottom wall layer covers part of the bottom surface of the reflective sheet. The light guiding structure according to claim 4, wherein the widths of the top wall layer and the bottom wall layer of the light shielding layer are respectively greater than or equal to 0.1 mm and less than or equal to 0.25 mm. The light guiding structure according to claim 4, wherein the thicknesses of the sidewall layer, the top wall layer and the bottom wall layer of the light shielding layer are respectively greater than or equal to 6 microns and less than or equal to 12 microns. The light guide structure as claimed in claim 1, wherein the light-shielding layer is formed on the side of the board through an ink printing process or a painting process. The light guiding structure according to claim 1, wherein the light shielding layer is a photocurable ink layer or a heat curable ink layer. A backlight module, comprising: a light source for emitting a light; and A light guide structure for conducting the light, the light guide structure includes: A plate body, including a light-transmitting plate, a light-guiding plate and a reflective sheet stacked in sequence from top to bottom, the light-guiding plate has a side, the light-transmitting plate has a side of the light-transmitting plate, and the reflecting sheet has a reflective The side of the sheet, the side of the light guide plate, the side of the light-transmitting plate and the side of the reflective sheet form a side of the plate body; and A light-shielding layer covers the side surface of the plate body, and the light-shielding layer is used to block the light emitted by the light source from exiting through the side surface of the light guide plate.

Images