Backlight module

Abstract

A backlight module includes a glass substrate, a light-emitting sheet, a light guide plate, and a reflective sheet. The light-emitting sheet is disposed below the glass substrate and has a light-emitting area and a light-shielding area. The light-emitting area is disposed corresponding to the glass substrate. The light-shielding area is disposed corresponding to at least a portion of the outer periphery of the glass substrate. The light guide plate is disposed below the light-emitting sheet and has a light-guiding area and a light-monopolating area. The light-guiding area is disposed corresponding to the light-emitting area. The light-monopolating area is configured to receive light emitted by a light-emitting element and guide the light to the light-guiding area. The guided light leaves the light-guiding area and propagates sequentially through the light-emitting area and the glass substrate. The reflective sheet is disposed below the light guide plate. This effectively increases the uniformity of light.

Description

Technical Field

[0001] This disclosure relates to a touchpad device, and more particularly to a backlight module used in a touchpad device. Background Technology

[0002] Traditional touchpad devices often have a rather monotonous and dull appearance, so computer peripheral manufacturers have developed backlight touchpad devices with excellent visual effects. The backlight module used in conventional backlight touchpad devices consists of two main components, from top to bottom: a light shield and a light guide plate.

[0003] A common method of applying adhesive is to cover the entire non-light-emitting area to avoid accidental touches, but this results in poor light emission efficiency (wasted in the non-light-emitting area). To increase light emission efficiency, another common method is to apply adhesive in a swivel pattern around the light-emitting area, but this can also lead to accidental touches. Furthermore, in modes where the entire surface needs to be illuminated, light leakage occurs around the backlight module, creating a bright line that results in a poor user experience.

[0004] Therefore, how to propose a backlight module that can solve the above problems is one of the issues that the industry is currently eager to invest research and development resources to address. Summary of the Invention

[0005] In view of this, one purpose of this disclosure is to propose a backlight module that can solve the above problems.

[0006] To achieve the above objectives, according to one embodiment of this disclosure, a backlight module includes a glass substrate, a light-emitting sheet, a light guide plate, and a reflective sheet. The light-emitting sheet is disposed below the glass substrate and has a light-emitting area and a light-shielding area. The light-emitting area is disposed corresponding to the glass substrate. The light-shielding area is disposed corresponding to at least a portion of the outer periphery of the glass substrate. The light guide plate is disposed below the light-emitting sheet and has a light-guiding area and a light-diffusing area. The light-guiding area is disposed corresponding to the light-emitting area. The light-diffusing area is configured to receive light emitted by a light-emitting element and guide the light to the light-guiding area. The guided light leaves the light guide area and propagates sequentially through the light-emitting area and the glass substrate. The reflective sheet is disposed below the light guide plate.

[0007] In one or more embodiments disclosed herein, the light-emitting sheet is joined to the reflective sheet by a light-shielding area.

[0008] In one or more embodiments disclosed herein, the light-emitting sheet has an opaque coating. The light-shielding area is defined by the opaque coating.

[0009] In one or more embodiments disclosed herein, the backlight module further includes a first light-shielding member. The first light-shielding member covers the light-diffusing area and the area above and outside the light-emitting element.

[0010] In one or more embodiments disclosed herein, the light guide plate has a light-emitting surface. The light-diffusing zone is defined by the orthographic projection of the first light-shielding member onto the light-emitting surface.

[0011] In one or more embodiments disclosed herein, the backlight module further includes a second light-shielding member. The second light-shielding member covers the light-shielding area, the side of the light guide plate, and a portion of the lower surface of the reflective sheet.

[0012] In one or more embodiments disclosed herein, the light-emitting sheet has a light-emitting surface. The light-shielding area is defined by the orthographic projection of the second light-shielding member onto the light-emitting surface.

[0013] In one or more embodiments disclosed herein, when viewed from the side of the glass substrate away from the light-emitting sheet, the second light-shielding member is U-shaped.

[0014] In one or more embodiments disclosed herein, when viewed from the side of the glass substrate away from the light-emitting sheet, the area of ​​the light guide plate is larger than the area of ​​the glass substrate.

[0015] To achieve the above objectives, according to another embodiment of this disclosure, a backlight module includes a light-emitting element, a reflective sheet, a light guide plate, a light-emitting sheet, and a glass substrate. The light-emitting element is disposed on a circuit board. The reflective sheet is disposed above the circuit board and has a side facing the light-emitting element. The light guide plate is disposed above the reflective sheet and has a light-diffusing area. The light-diffusing area has a side facing the light-emitting element. The light-diffusing area is configured to receive light emitted by the light-emitting element. The light-emitting sheet is disposed above the light guide plate and has a side facing the light-emitting element, a light-emitting area, a first light-shielding area, and a second light-shielding area. The first light-shielding area is adjacent to the side of the light-emitting sheet and is disposed corresponding to the light-diffusing area. The glass substrate is disposed correspondingly above the light-emitting area. The second light-shielding area surrounds at least a portion of the outer periphery of the glass substrate. Light exits the light guide plate and propagates sequentially through the light-emitting area and the glass substrate.

[0016] In one or more embodiments disclosed herein, the light-emitting sheet is joined to the reflective sheet via a second light-shielding area.

[0017] In one or more embodiments disclosed herein, the light-emitting sheet has an opaque coating. The second light-shielding area is defined by the opaque coating.

[0018] In one or more embodiments disclosed herein, the backlight module further includes a first light-shielding member. The first light-shielding member covers at least a portion of the first light-shielding area, the area above and outside the light-emitting element, and the area outside the circuit board.

[0019] In one or more embodiments disclosed herein, the light guide plate has a light-emitting surface. The light-diffusing zone is defined by the orthographic projection of the first light-shielding member onto the light-emitting surface.

[0020] In one or more embodiments disclosed herein, the backlight module further includes a second light-shielding member. The second light-shielding member covers the second light-shielding area, the side of the light guide plate, and a portion of the lower surface of the reflective sheet.

[0021] In one or more embodiments disclosed herein, the light-emitting sheet has a light-emitting surface. The second light-shielding area is defined by the orthographic projection of the second light-shielding member onto the light-emitting surface.

[0022] In one or more embodiments disclosed herein, when viewed from the side of the glass substrate away from the light-emitting sheet, the second light-shielding member is U-shaped.

[0023] In one or more embodiments disclosed herein, when viewed from the side of the glass substrate away from the light-emitting sheet, the area of ​​the light guide plate is larger than the area of ​​the glass substrate.

[0024] In one or more embodiments disclosed herein, when viewed from the side of the glass substrate away from the light-emitting sheet, the area of ​​the light guide plate is smaller than the area of ​​the light-emitting sheet.

[0025] In summary, in the backlight module disclosed herein, by arranging the light-shielding area on the light-emitting plate between the glass substrate and the light guide plate to correspond to at least a portion of the outer periphery of the glass substrate, and by using the first and second light-shielding members to jointly cover all sides of the light guide plate, the problem of light leakage causing a bright line to appear on the light-emitting surface of the light guide plate due to light leaving from the side of the light guide plate can be effectively avoided. Furthermore, by first receiving the light emitted by the light-emitting element in the light-diffusing area of ​​the light guide plate, and then guiding the light away from the light guide plate in the light-guiding area, the uniformity of the light can be effectively increased.

[0026] The above description is only used to illustrate the problem to be solved by this disclosure, the technical means to solve the problem, and the effects produced, etc. The specific details of this disclosure will be described in detail in the following implementation method and related drawings. Attached Figure Description

[0027] To make the above and other objects, features, advantages and embodiments disclosed herein more apparent and understandable, the accompanying drawings are described below:

[0028] Figure 1 A perspective view of an electronic device according to an embodiment of this disclosure is provided;

[0029] Figure 2 A partial cross-sectional schematic diagram of an electronic device according to an embodiment of the present disclosure is provided.

[0030] Figure 3 A top view is provided to illustrate some components of a backlight module according to one embodiment of this disclosure;

[0031] Figure 4 This is a partial cross-sectional schematic diagram illustrating an electronic device according to an embodiment of the present disclosure.

[0032] [Symbol Explanation]

[0033] 100: Electronic devices

[0034] 110: Host

[0035] 111: Shell

[0036] 111a: Opening

[0037] 120: Monitor

[0038] 200, 300: Backlight module

[0039] 210: Glass substrate

[0040] 220,320: light emission film

[0041] 221,321: light emission area

[0042] 222, 322: First shaded zone

[0043] 223, 323: Second shading zone

[0044] 230: Light guide plate

[0045] 231: Light Guide Area

[0046] 232: Uniform Lighting Zone

[0047] 240: Circuit board

[0048] 250: Light-emitting element

[0049] 260, 360: Reflective sheet

[0050] 271: First light-shielding component

[0051] 272,372: Second light-shielding component

[0052] 281, 282, 283, 284, 285, 286: Connectors

[0053] 290: Touch circuit board Detailed Implementation

[0054] The following describes several embodiments of this disclosure with reference to the accompanying drawings. For clarity, many practical details will be described in the following description. However, it should be understood that these practical details should not be used to limit this disclosure. That is, in some embodiments of this disclosure, these practical details are not essential. Furthermore, for the sake of simplicity in the drawings, some conventional structures and elements will be shown in a simple schematic manner.

[0055] Please refer to Figure 1This is a perspective view illustrating an electronic device 100 according to an embodiment of the present invention. Figure 1 As shown, in this embodiment, the electronic device 100 includes a host 110, a display 120, and a touchpad device. The touchpad device is an input device disposed on the host 110, but the present invention is not limited thereto. In practical applications, the touchpad device can also be an electronic product that uses a touchpad as an input or operation interface (e.g., a personal digital assistant, a keyboard including a touchpad, etc.). In other words, the concept of the touchpad device of the present invention can be applied to any electronic product that uses a touchpad as an input or operation interface. The structure, function, and connection and operation relationship between some of the components included in the touchpad device will be described in detail below.

[0056] Please refer to Figure 2 This is a partial cross-sectional schematic diagram illustrating an electronic device 100 according to an embodiment of the present disclosure. Figure 2 As shown, in this embodiment, the touchpad device is disposed within the host 110 and includes a backlight module 200 and a touch circuit board 290. The touch circuit board 290 is disposed below the backlight module 200. The backlight module 200 includes a glass substrate 210, a light-emitting sheet 220, a light guide plate 230, a circuit board 240, a light-emitting element 250, and a reflective sheet 260. The glass substrate 210 is exposed through an opening 111a in the housing 111 of the host 110. The outer periphery of the glass substrate 210 is adjacent to the inner periphery of the opening 111a and has substantially the same shape. The light-emitting sheet 220 is disposed below the glass substrate 210 and has a light-emitting area 221, a first light-shielding area 222, and a second light-shielding area 223. The light-emitting area 221 of the light-emitting sheet 220 is vertically corresponding to the glass substrate 210. The second light-shielding area 223 of the light-emitting sheet 220 is vertically corresponding to at least a portion of the outer periphery of the glass substrate 210. A light guide plate 230 is disposed below the light emitting plate 220 and has a light guiding area 231 and a light dispersing area 232. The light guiding area 231 of the light guide plate 230 and the light emitting area 221 of the light emitting plate 220 are vertically corresponding. A circuit board 240 is disposed below the light guide plate 230. A light-emitting element 250 is disposed on the circuit board 240. A reflective sheet 260 is disposed above the circuit board 240. The reflective sheet 260, the light dispersing area 232 of the light guide plate 230, and the light emitting plate 220 each have a left side facing the light emitting element 250. The first light-shielding area 222 of the light emitting plate 220 is adjacent to its left side and is vertically corresponding to the light dispersing area 232 of the light guide plate 230. The light dispersing area 232 of the light guide plate 230 is configured to receive the light emitted by the light emitting element 250 and guide the light to the light guiding area 231. After being guided, the light exits from the light guide area 231 and propagates sequentially through the light emission area 221 and the glass substrate 210. The reflector 260 is disposed below the light guide plate 230.

[0057] Under the aforementioned structural configuration, the light emitted by the light-emitting element 250 will first be uniformly mixed in the light-monopolizing area 232 of the light guide plate 230, and then leave the light guide plate 230 from the light guide area 231 of the light guide plate 230, thus effectively increasing the uniformity of light.

[0058] In some embodiments, the light-emitting plate 220 is a diffuser to increase the uniformity of light, but this disclosure is not limited thereto.

[0059] like Figure 2 As shown, in this embodiment, the backlight module 200 further includes a first light-shielding member 271. The first light-shielding member 271 covers the light-diffusing area 232 of the light guide plate 230 and the area above and outside the light-emitting element 250. The light guide plate 230 has a light-emitting surface (i.e., the light guide plate 230 on...). Figure 2 (The upper surface of the light guide plate 230). In some embodiments, the light-diffusing area 232 of the light guide plate 230 is defined by the orthographic projection of the first light-shielding member 271 onto the light-emitting surface of the light guide plate 230, but this disclosure is not limited thereto. In some embodiments, the first light-shielding area 222 is defined by the orthographic projection of the first light-shielding member 271 onto the light-emitting plate 220, but this disclosure is not limited thereto.

[0060] In some embodiments, the material of the first light-shielding member 271 includes plastic, but this disclosure is not limited thereto. In some embodiments, the first light-shielding member 271 is a black polyester film (Mylar), but this disclosure is not limited thereto.

[0061] like Figure 2 As shown, in this embodiment, the backlight module 200 further includes a second light-shielding member 272. The second light-shielding member 272 covers the second light-shielding area 223. The light-emitting sheet 220 has a light-emitting surface (i.e., the light-emitting sheet 220 is located on...). Figure 2 (the upper surface of the light-shielding area 223). The second light-shielding area 223 is defined by the orthographic projection of the second light-shielding member 272 onto the light-emitting surface of the light-emitting plate 220.

[0062] like Figure 2 As shown, in this embodiment, the second light-shielding member 272 is an opaque coating. The second light-shielding area 223 of the light-emitting sheet 220 is defined by the opaque coating. In this embodiment, the opaque coating is applied to the side of the light-emitting sheet 220 away from the light guide plate 230, but this disclosure is not limited thereto. In practical applications, the opaque coating may be applied to the side of the light-emitting sheet 220 closer to the light guide plate 230.

[0063] like Figure 2 As shown, in this embodiment, the light-emitting sheet 220 and the reflective sheet 260 are joined at the right side of the light guide plate 230 by the second light-shielding area 223. In this way, the second light-shielding area 223 of the light-emitting sheet 220 and the reflective sheet 260 can jointly cover the side of the light guide plate 230.

[0064] With the aforementioned structural configuration, the backlight module 200 of this embodiment can effectively prevent light leakage from the light exiting from the side of the light guide plate 230 and causing a bright line to appear on the light-emitting surface of the light guide plate 230 by means of the first light-shielding member 271 and the second light-shielding member 272.

[0065] Please refer to Figure 3 This is a top view illustrating some components of a backlight module 200 according to an embodiment of the present disclosure. Specifically, these components include a glass substrate 210, a light-emitting sheet 220, and a light guide plate 230 (in...). Figure 3 (represented by dashed lines), first light-shielding member 271 and second light-shielding member 272. For example... Figure 3 As shown, in this embodiment, when viewed from the side of the glass substrate 210 away from the light-emitting sheet 220, the area of ​​the light guide plate 230 is smaller than the area of ​​the light-emitting sheet 220. Furthermore, at least three sides of the outer periphery of the light guide plate 230 are within the outer periphery of the light-emitting sheet 220. Additionally, when viewed from the side of the glass substrate 210 away from the light-emitting sheet 220, the second light-shielding member 272 is substantially U-shaped and corresponds to the aforementioned at least three sides of the light guide plate 230, while the first light-shielding member 271 corresponds to the fourth side of the light guide plate 230. Therefore, in this embodiment, the second light-shielding area 223 of the light-emitting sheet 220 and the reflective sheet 260 together cover three sides of the light guide plate 230 (i.e., the side of the light guide plate 230 facing the light-emitting element 250), while the first light-shielding member 271 covers the fourth side of the light guide plate 230.

[0066] like Figure 3 As shown, in this embodiment, when viewed from the side of the glass substrate 210 away from the light-emitting sheet 220, the area of ​​the light guide plate 230 is larger than the area of ​​the glass substrate 210. Furthermore, the outer periphery of the glass substrate 210 is within the outer periphery of the light guide plate 230. This allows the side surface of the light guide plate 230 to be as far away from the glass substrate 210 as possible, thereby effectively reducing the amount of light reaching the outer periphery of the glass substrate 210 from the side surface of the light guide plate 230. Moreover, by positioning the outer periphery of the light guide plate 230 and the first light-shielding member 271 and the second light-shielding member 272 covering the side surface of the light guide plate 230 outside the opening 111a of the housing 111, the first light-shielding member 271 and the second light-shielding member 272 can be prevented from being seen by the user through the opening 111a.

[0067] like Figure 2As shown, in this embodiment, the backlight module 200 further includes connectors 281, 282, 283, 284, 285, and 286. The glass substrate 210 and the light-emitting sheet 220 are interconnected via connector 281. The light-emitting sheet 220 and the light guide plate 230 are interconnected via connector 282. The light guide plate 230 and the reflective sheet 260 are interconnected via connector 283. The circuit board 240 and the reflective sheet 260 are interconnected via connector 284. The touch circuit board 290 and the reflective sheet 260 are interconnected via connector 285. The second light-shielding area 223 of the light-emitting sheet 220 is joined to the reflective sheet 260 via connector 286.

[0068] In some embodiments, at least one of connectors 281, 282, and 283 is optical clear adhesive (OCA), but this disclosure is not limited thereto. In some embodiments, at least one of connectors 284 and 285 is adhesive tape, but this disclosure is not limited thereto. In some embodiments, connector 286 is an opaque adhesive layer, but this disclosure is not limited thereto.

[0069] Please refer to Figure 4 This is a partial cross-sectional schematic diagram illustrating an electronic device 100 according to an embodiment of the present disclosure. Figure 4 As shown, in this embodiment, the touchpad device includes a backlight module 300 and a touch circuit board 290. The backlight module 300 includes a glass substrate 210, a light-emitting sheet 320, a light guide plate 230, a circuit board 240, a light-emitting element 250, a reflective sheet 360, a first light-shielding member 271, a second light-shielding member 372, and connectors 281, 282, 283, 284, and 285, wherein the glass substrate 210, light guide plate 230, circuit board 240, light-emitting element 250, first light-shielding member 271, and connectors 281, 282, 283, 284, and 285 are the same as... Figure 2 The embodiments shown are described above, and therefore, the descriptions of these components can be found in the relevant preceding text, and will not be repeated here. Compared to Figure 2 The embodiment shown provides a modified light-emitting sheet 320, a reflective sheet 360, and a second light-shielding member 372.

[0070] Specifically, in this embodiment, the light-emitting sheet 320 and the reflective sheet 360 do not extend to the right side of the light guide plate 230, therefore they are not joined at the right side of the light guide plate 230. Instead, in this embodiment, the second light-shielding member 372 covers the second light-shielding area 323 of the light-emitting sheet 320, the side surface of the light guide plate 230 (except for the side of the light guide plate 230 facing the light-emitting element 250), and a portion of the lower surface of the reflective sheet 360. In this way, the second light-shielding member 372 can cover the side surface of the light guide plate 230 to prevent light leakage from the side of the light guide plate 230, which would cause a bright line to appear on the light-emitting surface of the light guide plate 230. Furthermore, the light-emitting area 321 of the light-emitting sheet 320 and the first light-shielding area 322 are defined the same as... Figure 2 The implementation methods shown are not described in detail here.

[0071] In some embodiments, the first light-shielding area 322 is defined by the orthographic projection of the first light-shielding member 271 onto the light-emitting plate 320, but this disclosure is not limited thereto. In some embodiments, the second light-shielding area 323 of the light-emitting plate 320 is defined by the second light-shielding member 372 onto the light-emitting surface of the light-emitting plate 220 (i.e., the light-emitting plate 320 on the light-emitting surface). Figure 4 Defined by the orthographic projection onto the upper surface of the (in). In some implementations, similar to Figure 3 In this embodiment, when viewed from the side of the glass substrate 210 away from the light-emitting plate 320, the second light-shielding member 372 is substantially U-shaped and corresponds to the aforementioned at least three sides of the light guide plate 230. In this way, the second light-shielding member 372 can cover three sides of the light guide plate 230 (i.e., except for the side of the light guide plate 230 facing the light-emitting element 250).

[0072] In some embodiments, the material of the second light-shielding member 372 includes plastic, but this disclosure is not limited thereto. In some embodiments, the second light-shielding member 372 is a black polyester film, but this disclosure is not limited thereto.

[0073] From the detailed description of the specific embodiments disclosed above, it is clear that by arranging the light-shielding area on the light-emitting plate between the glass substrate and the light guide plate to correspond to at least a portion of the outer periphery of the glass substrate, and by having the first and second light-shielding members jointly cover all sides of the light guide plate, the problem of light leakage causing a bright line to appear on the light-emitting surface of the light guide plate due to light leaving from the side of the light guide plate can be effectively avoided. Furthermore, by having the light guide plate first receive the light emitted by the light-emitting element in the light-diffusing area, and then guide the light away from the light guide plate in the light-guiding area, the uniformity of the light can be effectively increased.

[0074] Although the present disclosure has been described above with reference to embodiments, it is not intended to limit the present disclosure. Any person skilled in the art may make various modifications and alterations without departing from the spirit and scope of the present disclosure. Therefore, the scope of protection of the present disclosure shall be determined by the scope defined in the appended claims.

Claims

1. A backlight module, characterized in that, Include: A light-emitting element is mounted on a circuit board; A reflective sheet is disposed above the circuit board and has one side facing the light-emitting element; A light guide plate is disposed above the reflector and has a light-diffusing area, the light-diffusing area having a side facing the light-emitting element, wherein the light-diffusing area is configured to receive the light emitted by the light-emitting element; A light-emitting sheet is disposed above the light guide plate and has a side facing the light-emitting element, a light-emitting area, a first light-shielding area, and a second light-shielding area. The first light-shielding area is adjacent to the side of the light-emitting sheet and is disposed opposite to the light-shielding area. A glass substrate is disposed above the light-emitting area, and the second light-shielding area surrounds at least a portion of an outer periphery of the glass substrate. The light, after leaving the light guide plate, propagates sequentially through the light-emitting area and the glass substrate.

2. The backlight module as described in claim 1, characterized in that, The light-emitting sheet is joined to the reflective sheet by the second light-shielding area.

3. The backlight module as described in claim 2, characterized in that, The light-emitting plate has an opaque coating, and the second light-shielding area is defined by the opaque coating.

4. The backlight module as described in claim 1, characterized in that, It further includes a first light-shielding member that covers at least a portion of the first light-shielding area, the top and outer side of the light-emitting element, and the outer side of the circuit board.

5. The backlight module as described in claim 4, characterized in that, The light guide plate has a light-emitting surface, and the light-diffusing area is defined by an orthographic projection of the first light-shielding member onto the light-emitting surface.

6. The backlight module as described in claim 1, characterized in that, It further includes a second light-shielding member that covers the second light-shielding area, one side of the light guide plate, and part of the lower surface of the reflective sheet.

7. The backlight module as described in claim 6, characterized in that, The light-emitting plate has a light-emitting surface, and the second light-shielding area is defined by an orthographic projection of the second light-shielding member onto the light-emitting surface.

8. The backlight module as described in claim 6, characterized in that, When viewed from the side of the glass substrate away from the light-emitting sheet, the second light-shielding member is U-shaped.

9. The backlight module as described in claim 1, characterized in that, When viewed from the side of the glass substrate away from the light-emitting sheet, one area of ​​the light guide plate is larger than one area of ​​the glass substrate.

10. The backlight module as described in claim 1, characterized in that, When viewed from the side of the glass substrate away from the light-emitting sheet, the area of ​​the light guide plate is smaller than the area of ​​the light-emitting sheet.

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