Automotive display and backlight module thereof

Abstract

A backlight module includes a housing, a light guide plate, a light source and an elastic retainer. The housing includes a backplate and a sidewall having a first wall portion. The light guide plate is disposed in the housing and has a first lateral edge and a recess. The first lateral edge corresponds to the first wall portion of the sidewall. The recess has a side opening at the first lateral edge. The light source is disposed in the housing and faces the light guide plate. The elastic retainer is disposed in the recess of the light guide plate and projects from the first lateral edge of the light guide plate via the side opening of the recess.

Description

Technical Field

[0001] This disclosure relates to an automotive display and its backlight module. Prior Technology

[0002] With the widespread adoption of automotive displays in modern vehicles, their applications now encompass navigation systems, entertainment systems, and vehicle information displays. However, during vehicle operation, these displays frequently experience various forms of vibration due to uneven road surfaces or external shocks. This vibration not only affects the stability of the displayed content but can also cause internal noise, negatively impacting the user's driving experience. To address this issue, the industry has proposed several technical solutions to reduce the impact of vibration on automotive displays.

[0003] In the past, some solutions focused on improving the display's casing structure. For example, some technologies used more robust casing materials, hoping to reduce the impact of vibration by increasing overall rigidity. However, while such designs can reduce the amplitude of vibration transmitted to the display's interior to some extent, vibration can still cause friction or impact between components due to design gaps and assembly tolerances between the backlight module and optical elements, resulting in noise. This noise not only affects the quietness of the vehicle interior but can also lead to long-term wear and tear on optical components, further shortening the display's lifespan. Summary of the Invention

[0004] In view of this, one purpose of this disclosure is to propose a highly reliable automotive display and backlight module.

[0005] According to some embodiments disclosed herein, a backlight module includes a housing, a light guide plate, a light source, and at least one elastic limiting member. The housing includes a back plate and a side wall, the side wall including a first wall portion. The light guide plate is disposed within the housing and has a first side edge and at least one groove. The first side edge corresponds to the first wall portion of the side wall, and the groove has a first side opening located on the first side edge. The light source is disposed within the housing and faces the light guide plate. The elastic limiting member is disposed in the groove of the light guide plate and protrudes from the first side edge of the light guide plate through the first side opening of the groove.

[0006] In one or more embodiments disclosed herein, the light source is disposed on a first wall portion of the sidewall and faces a first side edge of the light guide plate. The light source includes a circuit board and a plurality of light-emitting elements disposed on the circuit board, with elastic limiting members located outside the light-emitting elements.

[0007] In one or more embodiments disclosed herein, the elastic limiting member abuts against the circuit board of the light source.

[0008] In one or more embodiments disclosed herein, the backlight module further includes a reflective sheet disposed between the light guide plate and the back plate, and an elastic limiting member disposed between the light guide plate, the reflective sheet and the circuit board of the light source.

[0009] In one or more embodiments disclosed herein, the first wall portion of the sidewall has an area not covered by the circuit board of the light source, and the elastic limiting member abuts against the aforementioned area of ​​the first wall portion.

[0010] In one or more embodiments disclosed herein, the elastic limiting member has a slope located on the side of the elastic limiting member adjacent to the light-emitting element.

[0011] In one or more embodiments disclosed herein, there are multiple elastic limiting members and grooves located on both sides of the light-emitting element.

[0012] In one or more embodiments disclosed herein, the light guide plate further has a second side edge adjacent to the first side edge. The groove of the light guide plate also has a second side opening located on the second side edge. An elastic limiting member protrudes from the second side edge of the light guide plate through the second side opening of the groove.

[0013] In one or more embodiments disclosed herein, the elastic limiting member is a bent structure.

[0014] In one or more embodiments disclosed herein, the elastic limiting member extends partially perpendicular to the first side of the light guide plate and partially parallel to the first side of the light guide plate.

[0015] According to some embodiments disclosed herein, an automotive display includes the aforementioned backlight module and display panel, with the backlight module disposed on the back of the display panel facing away from it.

[0016] In summary, the backlight module disclosed herein includes a housing, a light guide plate disposed within the housing, and an elastic limiting member. The light guide plate has a groove, and the elastic limiting member is fixedly installed in the groove of the light guide plate and protrudes from the edge of the light guide plate. When the light guide plate expands and contracts due to thermal expansion and contraction, causing gaps between the light guide plate and other components, the elastic limiting member protruding from the edge of the light guide plate can prevent the light guide plate from colliding with other components and generating abnormal noise. Therefore, the backlight module disclosed herein can be used in environments with large temperature variations and high vibration (e.g., vehicles). Simple Explanation of the Diagram

[0017] To make the above and other objects, features, advantages and embodiments disclosed herein more apparent and understandable, the accompanying drawings are described below: Figure 1 is a perspective view illustrating a display device according to an embodiment of the present disclosure. Figure 2 is a cross-sectional view of the display device shown in Figure 1 at the mark of line segment 2-2'. Figure 3 is a schematic front view showing some components of the backlight module of the display device shown in Figure 1. Figure 4 is an exploded view of the light guide plate and the first elastic limiting member shown in Figure 3. Figure 5 is a partial enlarged view illustrating a backlight module according to another embodiment of this disclosure. Figure 6 is a partially enlarged view illustrating another embodiment of the backlight module according to this disclosure. Implementation

[0018] To make the description of this disclosure more detailed and complete, reference may be made to the accompanying drawings and the various embodiments described below. The elements in the drawings are not drawn to scale and are provided for illustrative purposes only. Many practical details are described below to provide a comprehensive understanding of this disclosure; however, those skilled in the art will understand that this disclosure can be practiced without one or more of these practical details, and therefore, these details should not be used to limit this disclosure.

[0019] Please refer to Figure 1. Figure 1 is a perspective view illustrating a display device 15 according to an embodiment of this disclosure. The display device 15 includes a display panel 16 (e.g., a liquid crystal display panel) and a backlight module 19. The display panel 16 has opposing first surfaces 17 and second surfaces 18 (see Figure 2), wherein the first surface 17 faces outward to display an image, that is, the first surface 17 is the display surface of the display panel 16. The second surface 18 is the back surface of the display panel 16, and the backlight module 19 is disposed facing the second surface 18 of the display panel 16. The backlight module 19 is configured to provide illumination to the display panel 16 so that the display panel 16 can display an image. The display device 15 disclosed herein may be an automotive display, but is not limited thereto.

[0020] As shown in Figure 1, the first surface 17 of the display panel 16 faces the first direction D1; in other words, the first direction D1 is the normal direction of the first surface 17 of the display panel 16. The display device 15 also has two edges extending along the second direction D2 and two other edges extending along the third direction D3. In some embodiments, the first direction D1, the second direction D2, and the third direction D3 are substantially perpendicular to each other.

[0021] It should be noted that the first direction D1, the second direction D2, and the third direction D3 are coordinate systems attached to the display device 15 and the backlight module 19. Therefore, as the orientation of the display device 15 and the backlight module 19 changes (for example, changing to the flat position shown in Figure 2), this coordinate system turns accordingly.

[0022] Please refer to Figures 2 and 3. Figure 2 is a cross-sectional view of the display device 15 shown in Figure 1 at the line segment 2-2', and Figure 3 is a schematic front view of some components of the backlight module 19 of the display device 15 shown in Figure 1. As shown, the backlight module 19 includes a housing 20, a light guide plate 30, and a light source 40. The housing 20 has a light outlet 29, and the display panel 16 is disposed facing the light outlet 29 of the housing 20. The light guide plate 30 and the light source 40 are disposed in the housing 20, and the light source 40 faces the light guide plate 30. The light source 40 is configured to emit light, and the light emitted by the light source 40 is guided by the light guide plate 30 through the light outlet 29 to illuminate the outside of the housing 20 and the display panel 16. The light source 40 is, for example, a light strip, and the light source 40 may include a circuit board 47 and a plurality of light-emitting elements 48 disposed on the circuit board 47. The light-emitting elements 48 may include light-emitting diodes (LEDs) or mini LEDs. The light guide plate 30 is a transparent element and can be made of polycarbonate (PC), polymethyl methacrylate (PMMA) or other suitable materials.

[0023] As shown in Figures 2 and 3, the housing 20 includes a back plate 21 and a side wall 22. The back plate 21 is opposite to the light outlet 29, while the side wall 22 is connected to the back plate 21 and bent relative to the back plate 21. The side wall 22 includes a first wall portion 221, and the light guide plate 30 has a first side edge 31, which corresponds to the first wall portion 221 of the side wall 22. The light source 40 is disposed on the first wall portion 221 of the side wall 22 and faces the first side edge 31 of the light guide plate 30. In other words, the backlight module 19 disclosed herein is an edge-lit backlight module. In some embodiments, the first wall portion 221 of the side wall 22 is located at the bottom of the backlight module, and the first wall portion 221 of the side wall 22 and the first side edge 31 of the light guide plate 30 extend substantially along a second direction D2.

[0024] As shown in Figures 2 and 3, in some embodiments, the sidewall 22 surrounds the backplate 21 on all four sides. Specifically, the sidewall 22 further includes two second wall portions 222 and a third wall portion 223, the third wall portion 223 being opposite to the first wall portion 221, and the second wall portions 222 being adjacent to the first wall portion 221. The two ends of the second wall portion 222 are respectively connected to the first wall portion 221 and the third wall portion 223. Correspondingly, the light guide plate 30 may have two second side edges 32 and a third side edge 33, the third side edge 33 being opposite to the first side edge 31, and the second side edge 32 being adjacent to the first side edge 31. The two ends of the second side edge 32 are respectively connected to the first side edge 31 and the third side edge 33. The second side edge 32 and the third side edge 33 correspond to the second wall portion 222 and the third wall portion 223 of the sidewall 22, respectively.

[0025] As shown in Figures 2 and 3, the backlight module 19 further includes at least one elastic limiting member disposed within the housing 20 and used to fix the position of the light guide plate 30. The elastic limiting member may include at least one first elastic limiting member 50P, which protrudes from the first side 31 of the light guide plate 30. The first elastic limiting member 50P restricts the movement of the light guide plate 30 in the third direction D3 and prevents the light guide plate 30 from impacting the light source 40 or the side wall 22 of the housing 20. Furthermore, the first elastic limiting member 50P is disposed outside the light-emitting element 48 of the light source 40 to avoid affecting the light emission of the light-emitting element 48. The elastic limiting member may contain an elastomeric material, such as rubber.

[0026] As shown in Figures 2 and 3, the light guide plate 30 also has at least one groove 35. In this embodiment, the groove 35 is located on the side of the light guide plate 30 facing the back plate 21. The groove 35 has a first side opening 36, which is located on the first side edge 31 of the light guide plate 30. A first elastic limiting member 50P is disposed in the groove 35 of the light guide plate 30 and protrudes from the first side edge 31 of the light guide plate 30 through the first side opening 36 of the groove 35. In Figure 3, the portion of the first elastic limiting member 50P located inside the groove 35 is shown as a dashed line, while the portion located outside the groove 35 is shown as a solid line. The shape of the groove 35 can match the shape of the first elastic limiting member 50P to facilitate the first elastic limiting member 50P being secured in the groove 35. Alternatively, the first elastic limiting member 50P can also be fixed to the light guide plate 30 using adhesive.

[0027] As shown in Figures 2 and 3, in this embodiment, the first elastic limiting member 50P, protruding from the first side 31 of the light guide plate 30, abuts against the circuit board 47 of the light source 40, which can limit the light guide plate 30 and prevent it from shifting. In addition, when the size of the light guide plate 30 shrinks significantly due to temperature changes, the light guide plate 30 may still shift. At this time, the first elastic limiting member 50P, protruding from the edge of the light guide plate 30, can prevent the light guide plate 30 from colliding with the light source 40 and producing noise. In other words, the first elastic limiting member 50P also provides a buffering function.

[0028] As shown in Figures 2 and 3, in some embodiments, the first elastic limiting member 50P and the grooves 35 of the light guide plate 30 are multiple and located on both sides of the light-emitting element 48 of the light source 40. For example, in the embodiment shown, the light guide plate 30 has a groove 35 at each corner of the first side 31, and a first elastic limiting member 50P is installed in each groove 35.

[0029] As shown in Figures 2 and 3, in some embodiments, the first elastic limiting member 50P has a slope 53 located on the side of the first elastic limiting member 50P adjacent to the light-emitting element 48. The design of the slope 53 on the first elastic limiting member 50P can prevent the first elastic limiting member 50P from blocking the light emitted by the light-emitting element 48, thus avoiding the creation of a dark area. In some embodiments, the first elastic limiting member 50P is a transparent element; for example, the first elastic limiting member 50P can be made of transparent rubber material, which can also achieve the effect of preventing the first elastic limiting member 50P from blocking the light emitted by the light-emitting element 48.

[0030] As shown in Figures 2 and 3, in some embodiments, the elastic limiting member further includes at least one second elastic limiting member 50Q, which is disposed on the second side 32 of the light guide plate 30 and abuts against the second wall portion 222 of the sidewall 22, thereby restricting the movement of the light guide plate 30 in the second direction D2. In some embodiments, the elastic limiting member further includes at least one third elastic limiting member 50R, which is disposed on the third side 33 of the light guide plate 30 and abuts against the third wall portion 223 of the sidewall 22, thereby restricting the movement of the light guide plate 30 in the third direction D3.

[0031] As shown in Figures 2 and 3, in the illustrated embodiment, the second elastic limiting member 50Q is clamped between the second wall portion 222 of the sidewall 22 and the second side edge 32 of the light guide plate 30, while the third elastic limiting member 50R is clamped between the third wall portion 223 of the sidewall 22 and the third side edge 33 of the light guide plate 30. In other embodiments, the second elastic limiting member 50Q and the third elastic limiting member 50R may have the same form as the first elastic limiting member 50P; that is, the second elastic limiting member 50Q and the third elastic limiting member 50R may also be disposed in the groove of the light guide plate 30 and partially protrude from the edge of the light guide plate 30.

[0032] As shown in Figures 2 and 3, in some embodiments, the backlight module 19 further includes a reflective sheet 45, which is disposed between the light guide plate 30 and the back plate 21 of the housing 20, and covers the back side of the light guide plate 30. The reflective sheet 45 can reflect light so that the light shines towards the display panel 16. In some embodiments, the reflective sheet 45 covers the groove 35 of the light guide plate 30, and a first elastic limiting member 50P is disposed between the light guide plate 30, the reflective sheet 45, and the circuit board 47 of the light source 40.

[0033] In some embodiments, the backplate 21 of the housing 20 has at least one groove 23 located on one side of the sidewall 22 and extending substantially parallel to the sidewall 22. The backlight module 19 may further include at least one pad 41 disposed in the groove 23, which provides support for the reflector 45 and the light guide plate 30. The pad 41 is, for example, an elongated pad. The pad 41 may contain an elastomeric material (e.g., rubber).

[0034] As shown in Figures 2 and 3, in some embodiments, the backlight module 19 further includes at least one optical film 70, which is disposed on the side of the light guide plate 30 away from the back plate 21; in other words, the light guide plate 30 is disposed between the back plate 21 and the optical film 70. The optical film 70 may include a diffuser, a prism, a brightness enhancement film, or other functional optical films. In some embodiments, the backlight module 19 includes a plurality of optical films 70, which are stacked with the light guide plate 30.

[0035] As shown in Figures 2 and 3, in some embodiments, the backlight module 19 further includes a frame 60 disposed on the housing 20 and configured to support the display panel 16. The frame 60 may have a light exit port 65 to allow light emitted from the light source 40 to illuminate the display panel 16. In some embodiments, the frame 60 includes a first portion 61 and a second portion 62 connected together. The first portion 61 covers the peripheral area of ​​the optical film 70, and the display panel 16 is disposed on the first portion 61. The second portion 62 of the frame 60 is bent relative to the first portion 61 and extends to the outside of the side wall 22 of the housing 20. The second portion 62 of the frame 60 may be fixed to the side wall 22 of the housing 20 by snap-fit, adhesive, or other suitable means.

[0036] Please refer to Figure 4 as well. Figure 4 is an exploded view illustrating the light guide plate 30 and the first elastic retaining member 50P shown in Figure 3. As shown in Figures 3 and 4, in some embodiments, the first elastic retaining member 50P is a bent structure, that is, the first elastic retaining member 50P includes at least two non-parallel extending portions. For example, in the illustrated embodiment, the first elastic retaining member 50P includes a first extension 51 and a second extension 52 that are not parallel to each other. Correspondingly, the groove 35 of the light guide plate 30 is a bent-shaped groove to accommodate the first elastic retaining member 50P. When the backlight module is in a high-temperature environment causing the various components to expand, the bent-shaped first elastic retaining member 50P is less likely to be squeezed out of the groove 35 of the light guide plate 30.

[0037] As shown in Figures 3 and 4, in some embodiments, the first extension 51 of the first elastic limiting member 50P extends substantially perpendicular to the first side 31 of the light guide plate 30, while the second extension 52 extends substantially parallel to the first side 31 of the light guide plate 30. In some embodiments, a ramp 53 is located at the corner of the first extension 51 and the second extension 52. The ramp 53 may have opposing first ends 56 and second ends 57, with the second end 57 being farther away from the light-emitting element 48 relative to the first end 56 in the second direction D2 and the third direction D3.

[0038] Please refer to Figure 5. Figure 5 is a partially enlarged view illustrating a backlight module according to another embodiment of this disclosure. The difference between this embodiment and the previous embodiment is that the first wall portion 221 of the sidewall 22 has an area N not covered by the circuit board 47 of the light source 40, and a first elastic limiting member 50P protruding from the first side edge 31 of the light guide plate 30 abuts against the area N of the first wall portion 221. This design can also provide the function of limiting and buffering the light guide plate 30.

[0039] Please refer to Figure 6. Figure 6 is a partially enlarged view illustrating a backlight module according to another embodiment of this disclosure. The difference between this embodiment and the previous embodiment is that the groove of the light guide plate 30A also has a second side opening 37, which is located on the second side 32 of the light guide plate 30A. In addition to protruding from the first side 31 of the light guide plate 30A, the first elastic limiting member 50PA also protrudes from the second side 32 of the light guide plate 30A through the second side opening 37 of the groove. The portion of the first elastic limiting member 50PA protruding from the second side 32 of the light guide plate 30A can abut against the second wall portion 222 of the sidewall 22. Therefore, in this embodiment, the first elastic limiting member 50PA can provide limiting and buffering functions in two directions.

[0040] In summary, the backlight module disclosed herein includes a housing, a light guide plate disposed within the housing, and an elastic limiting member. The light guide plate has a groove, and the elastic limiting member is fixedly installed in the groove of the light guide plate and protrudes from the edge of the light guide plate. When the light guide plate expands and contracts due to thermal expansion and contraction, causing gaps between the light guide plate and other components, the elastic limiting member protruding from the edge of the light guide plate can prevent the light guide plate from colliding with other components and generating abnormal noise. Therefore, the backlight module disclosed herein can be used in environments with large temperature variations and high vibration (e.g., vehicles).

[0041] Although this disclosure has been described above with reference to embodiments, it is not intended to limit this disclosure. Anyone skilled in the art can make various modifications and refinements without departing from the spirit and scope of this disclosure. Therefore, the scope of protection of this disclosure shall be determined by the appended claims.

[0042] 15: Display device 16: Display panel 17: First Surface 18: Second Surface 19: Backlight Module 20: Shell 21: Back panel 22: Sidewall 221: First wall section 222: Second wall section 223: Third wall section 23: Trench 29:Light exit 30, 30A: Light guide plate 31: First side 32: Second side 33: Third side 35: Groove 36: First side opening 37: Second side opening 40: Light source 41: Gasket 45: Reflective sheet 47: Circuit Board 48: Light-emitting element 50P, 50PA: First elastic limiting element 50Q: Second elastic limiting component 50R: Third elastic limiting component 51: First Extension 52: Second extension 53: Incline 56: First end 57: Second end 60: Frame 61: Part One 62: Part Two 65:Light exit 70: Optical film D1: First Direction D2: Second Direction D3: Third direction N: Region

Claims

1. A backlight module, comprising: a housing including a back plate and a side wall, the side wall including a first wall portion; a light guide plate disposed in the housing and having a first side edge and at least one groove, the first side edge corresponding to the first wall portion of the side wall, the at least one groove having a first side opening located on the first side edge; a light source disposed in the housing and facing the light guide plate; and at least one elastic limiting member disposed in the at least one groove of the light guide plate and protruding from the first side edge of the light guide plate through the first side opening of the at least one groove.

2. The backlight module as claimed in claim 1, wherein the light source is disposed on the first wall portion of the sidewall and facing the first side of the light guide plate, wherein the light source includes a circuit board and a plurality of light-emitting elements disposed on the circuit board, and the at least one elastic limiting member is located outside the light-emitting elements.

3. The backlight module as described in claim 2, wherein the at least one resilient retaining member abuts against the circuit board of the light source.

4. The backlight module as described in claim 3 further includes a reflective sheet disposed between the light guide plate and the back plate, and the at least one elastic limiting member is disposed between the light guide plate, the reflective sheet and the circuit board of the light source.

5. The backlight module as claimed in claim 2, wherein the first wall portion of the sidewall has an area not covered by the circuit board of the light source, and the at least one resilient retaining member abuts against the area of ​​the first wall portion.

6. The backlight module as claimed in claim 2, wherein the at least one elastic limiting member has a ramp located on the side of the at least one elastic limiting member adjacent to the light-emitting elements.

7. The backlight module as claimed in claim 2, wherein the at least one elastic limiting member and the at least one groove are multiple and located on both sides of the light-emitting elements.

8. The backlight module as claimed in claim 1, wherein the light guide plate further has a second side adjacent to the first side, the at least one groove of the light guide plate further has a second side opening located on the second side, and the at least one elastic limiting member protrudes from the second side of the light guide plate through the second side opening of the at least one groove.

9. The backlight module as described in claim 1, wherein the at least one elastic limiting member is a bent structure.

10. The backlight module as claimed in claim 9, wherein the at least one elastic limiting member extends partially perpendicular to the first side of the light guide plate and partially extends parallel to the first side of the light guide plate.

11. An automotive display comprising: a display panel; and a backlight module as described in any one of claims 1 to 10, disposed on a rear side facing the display panel.

Images