Display device and backlight module thereof

Abstract

A backlight module includes a housing accommodating a light guide plate, a light source and an elastic retainer. The housing includes a backplate and a sidewall. The sidewall has a first wall portion having two first openings and a second opening. The second opening is located between the two first openings and has a greater area than each first opening. The light guide plate has a first lateral edge corresponding to the first wall portion of the sidewall. The elastic retainer includes a main body and two protrusions. The main body is disposed between the first wall portion of the sidewall and the first lateral edge of the light guide plate. The two protrusions extend into and engage the two first openings, respectively.

Description

[Technical Field]

[0001] This disclosure relates to a display device and its backlight module. [Previous Technology]

[0002] The structural design of traditional automotive displays and backlight modules has shortcomings. In high-temperature environments or when subjected to vibration and shaking, the light guide plate is prone to deformation or displacement. [Summary of the Invention]

[0003] In view of this, one object of the present disclosure is to provide a display device and backlight module with high reliability.

[0004] According to some embodiments disclosed herein, a backlight module includes a housing, a light guide plate, a light source, and an elastic limiting member. The housing includes a back plate and a side wall. The side wall includes a first wall portion having two first openings and a second opening, the second opening being located between the two first openings, and the area of ​​the second opening being larger than the area of ​​any of the first openings. The light guide plate is disposed in the housing and has a first side edge corresponding to the first wall portion of the side wall. The light source is disposed in the housing and configured to emit light facing the light guide plate. The elastic limiting member includes a body and two protrusions, the body being disposed between the first wall portion of the side wall and the first side edge of the light guide plate, the two protrusions connecting to the body and respectively engaging with the two first openings of the first wall portion.

[0005] In one or more embodiments disclosed herein, the body of the elastic limiting member includes a plurality of bearing structures, the bearing structures are disposed on the side of the body facing the light guide plate, and at least a portion of the bearing structures abut against the light guide plate, and a groove is provided between any two adjacent bearing structures.

[0006] In one or more embodiments disclosed herein, the supporting structure includes two first supporting structures and a second supporting structure located between the two first supporting structures. The second supporting structure protrudes further from the body than either of the first supporting structures.

[0007] In one or more embodiments disclosed herein, the first supporting structure has a substantially trapezoidal shape, and the second supporting structure has a substantially triangular shape. The position of the second supporting structure corresponds to the second opening of the first wall portion of the sidewall.

[0008] In one or more embodiments disclosed herein, the two outermost supporting structures each have an inclined surface, which is located on the outside of the supporting structure.

[0009] In one or more embodiments disclosed herein, the backlight module further includes an optical film disposed on the side of the light guide plate away from the back plate, and having a third side edge corresponding to the first side edge of the light guide plate. The elastic limiting member also includes a baffle extending from the side of the body away from the back plate and located between the third side edge of the optical film and the first wall portion of the sidewall.

[0010] In one or more embodiments disclosed herein, in a direction perpendicular to the first wall portion of the sidewall, the baffle is recessed relative to the main body, and the third side of the optical film extends at least partially beyond the first side of the light guide plate.

[0011] In one or more embodiments disclosed herein, in a direction perpendicular to the back plate, the height of the second opening of the first wall portion of the sidewall is greater than the height of the body of the elastic limiting member and less than the height of the baffle.

[0012] According to some embodiments of this disclosure, a display device includes a display panel and a backlight module disposed on the back side facing the display panel. The backlight module includes a housing, a light guide plate, an optical film, a light source, and an elastic limiting member. The housing includes a back plate and a side wall, the side wall including a first wall portion having an opening. The light guide plate is disposed in the housing and has a first side edge corresponding to the first wall portion of the side wall. The optical film is disposed on the side of the light guide plate away from the back plate and has a third side edge corresponding to the first side edge of the light guide plate. The light source is disposed in the housing and configured to emit light facing the light guide plate. The elastic limiting member covers the opening and includes a body and a baffle. The body is disposed between the first wall portion of the side wall and the first side edge of the light guide plate and abuts against the first wall portion. The baffle extends from the side of the body away from the back plate and is located between the third side edge of the optical film and the first wall portion of the side wall. The body includes a plurality of supporting structures disposed on the side of the body facing the light guide plate and abuts against the light guide plate. There is a groove between any two adjacent supporting structures.

[0013] According to some embodiments of this disclosure, a display device includes a display panel and a backlight module disposed on the back side facing the display panel. The backlight module includes a housing, a light guide plate, an optical film, a light source, and an elastic limiting member. The housing includes a back plate and a side wall, the side wall including a first wall portion having an opening. The light guide plate is disposed in the housing and has a first side edge corresponding to the first wall portion of the side wall. The optical film is disposed on the side of the light guide plate away from the back plate and has a third side edge corresponding to the first side edge of the light guide plate. The light source is disposed in the housing and configured to emit light facing the light guide plate. The elastic limiting member includes a body and a baffle. The body is disposed between the first wall portion of the side wall and the first side edge of the light guide plate, and the baffle extends from the side of the body away from the back plate and is located between the third side edge of the optical film and the first wall portion of the side wall. In a direction perpendicular to the back plate, the height of the opening of the first wall portion of the side wall is greater than the height of the body of the elastic limiting member and less than the height of the baffle.

[0014] In summary, the backlight module disclosed herein includes an elastic limiting member disposed between the light guide plate and the side wall of the housing, the elastic limiting member being used to fix the light guide plate. The above-described structural configuration of the light guide plate, the elastic limiting member, and the side wall helps to improve the reliability of the backlight module, enabling it to be used in environments with large temperature variations and high vibration (e.g., vehicles).

Implementation Method

[0015] 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 should 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.

[0016] Please refer to Figure 1. Figure 1 is a perspective view illustrating a display device 15 according to an embodiment of the present disclosure. The display device 15 includes a display panel 16 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 is, for example, an automotive display, the display panel 16 is, for example, a liquid crystal display panel, and the backlight module 19 is, for example, an edge-lit backlight module, but is not limited thereto.

[0017] 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.

[0018] 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, when the orientation of the display device 15 and the backlight module 19 changes (for example, when it is converted to an upright or flat position), this coordinate system also turns accordingly.

[0019] Please refer to Figure 2. Figure 2 is a cross-sectional view of the display device 15 shown in Figure 1 at the mark 2-2'. 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 at 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 is configured to emit light towards the light guide plate 30. The light emitted by the light source 40 enters the light guide plate 30 and then exits towards the light outlet 29, illuminating the display panel 16. The light source 40 is, for example, a lamp board or a light strip, and may include a circuit board and a plurality of light-emitting diode elements (LEDs), mini LEDs, or other light-emitting elements disposed on the circuit board. The backlight module 19 also includes at least one elastic limiting member 50, which is disposed in the housing 20 and used to fix the position of the light guide plate 30.

[0020] As shown in Figure 2, the housing 20 includes a connected 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 bent from the back plate 21 and extends from the back plate 21. The side wall 22 is, for example, perpendicular to the back plate 21, or for example, the side wall 22 may extend from the back plate 21 along a first direction D1. In some embodiments, the back plate 21 and the side wall 22 are integrally formed; in other words, the housing 20 is a one-piece housing. The side wall 22 surrounds the back plate 21 on all four sides, but is not limited thereto. The side wall 22 includes a first wall portion 221, and the light guide plate 30 has a first side edge 31. When the light guide plate 30 is disposed in the housing 20, the first side edge 31 corresponds to the first wall portion 221 of the side wall 22. The elastic limiting member 50 is clamped between the first wall portion 221 of the sidewall 22 and the first side edge 31 of the light guide plate 30. In other words, the elastic limiting member 50 and the sidewall 22, as well as the elastic limiting member 50 and the light guide plate 30, are in a tight fit. The elastic limiting member 50 may contain an elastomeric material (e.g., rubber). The elastic limiting member 50 may be an integrally formed element.

[0021] As shown in Figure 2, the sidewall 22 further includes a second wall portion 222, and the light guide plate 30 further has a second side edge 32. When the light guide plate 30 is disposed in the housing 20, the second side edge 32 corresponds to the second wall portion 222 of the sidewall 22. In some embodiments, the backlight module 19 is a side-lit backlight module, and the light source 40 is disposed between the second wall portion 222 of the sidewall 22 and the second side edge 32 of the light guide plate 30, and emits light toward the second side edge 32 of the light guide plate 30.

[0022] As shown in Figure 2, the second wall portion 222 and the first wall portion 221 are located on opposite sides of the side wall 22. In the illustrated embodiment, the second wall portion 222 and the first wall portion 221 are located on opposite sides of the housing 20 in the third direction D3. The second side edge 32 and the first side edge 31 are located on opposite sides of the light guide plate 30. In the illustrated embodiment, the second side edge 32 and the first side edge 31 are located on opposite sides of the light guide plate 30 in the third direction D3. Therefore, in the illustrated embodiment, the elastic limiting member 50 is provided on the side of the light guide plate 30 away from the light source 40. The first side edge 31 of the light guide plate 30 abuts against the elastic limiting member 50, while the second side edge 32 may abut against the light source 40 or the second wall portion 222 of the side wall 22. In some embodiments, a buffer member (not shown) is provided on the light source 40 or the second wall portion 222 of the side wall 22, and the second side edge 32 of the light guide plate 30 may abut against the buffer member. In some embodiments, the backlight module 19 may include a plurality of elastic limiting members 50 disposed on a plurality of wall portions of the sidewall 22 to correspondingly abut against a plurality of sides of the light guide plate 30, for example, corresponding to abutting against the first side 31 of the light guide plate 30 away from the light source 40 and the other two sides adjacent to the first side 31.

[0023] As shown in Figure 2, 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 side of the light guide plate 30 near the back plate 21, i.e., the back side of the light guide plate 30. The reflective sheet 45 can reflect light so that the light is directed toward the display panel 16 located at the light outlet 29. In some embodiments, the back plate 21 of the housing 20 also has at least one recess 23, which is formed inside the side wall 22. The backlight module 19 may further include at least one first pad 41, which is disposed in the recess 23 and can support the reflective sheet 45 and the light guide plate 30, i.e., the first pad 41 is located between the back plate 21 and the reflective sheet 45 or the light guide plate 30. In some embodiments, the recess 23 is a groove extending substantially parallel to the side wall 22, and the first pad 41 is an elongated pad disposed along the recess 23. The first gasket 41 may contain an elastomeric material (e.g., rubber).

[0024] As shown in Figure 2, 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, that is, on the front side or light-emitting surface of the light guide plate 30. 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.

[0025] As shown in Figure 2, 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 display panel 16 may be disposed outside the frame 60 as shown, or it may be disposed inside the frame 60. The frame 60 may have a light outlet 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 is substantially parallel to the back plate 21 and 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 from the first portion 61 and extends outward along the opposite direction of the first direction D1 to the outside of the side wall 22 of the housing 20. In some embodiments, the second portion 62 of the frame 60 is substantially parallel to the side wall 22 of the housing 20. The second portion 62 of the frame 60 can be fixed to the side wall 22 of the housing 20 by snap-fit, adhesive, or other suitable means. In some embodiments, the backlight module 19 further includes at least one second spacer 42 disposed between the optical film 70 and the first portion 61 of the frame 60. In some embodiments, the second spacer 42 is adhesive to adhere and fix the optical film 70 to the frame 60. In some embodiments, the display panel 16 is disposed within the frame 60, and the second spacer 42 can adhere and fix the display panel 16 to the frame 60.

[0026] Please refer to Figures 3 and 4 together. Figure 3 is an assembly diagram of the housing 20 and the elastic limiting member 50 of the backlight module 19 of the display device 15 shown in Figure 1, and Figure 4 is an exploded view of the housing 20 and the elastic limiting member 50 of the backlight module 19 of the display device 15 shown in Figure 1. As shown in Figures 2 to 4, the elastic limiting member 50 includes a body 53 and two first protrusions 51. When the elastic limiting member 50 is assembled with the first wall portion 221, the body 53 is disposed between the first wall portion 221 of the side wall 22 and the first side edge 31 of the light guide plate 30, and abuts against the first wall portion 221, while the two first protrusions 51 are disposed on both sides of the body 53 and protrude from the side of the body 53 away from the light guide plate 30. The first wall portion 221 of the side wall 22 has two first openings 241, and the two first protrusions 51 extend into the two first openings 241 respectively. On the second direction D2 extending from the first wall portion 221, the width of each first opening 241 is greater than the width of the corresponding first protrusion 51. For example, the width of each first opening 241 can be at least twice the width of the corresponding first protrusion 51. In this way, when the light guide plate 30 expands due to high temperature and squeezes the elastic limiting member 50, the first opening 241 of the side wall 22 can provide space for the elastic limiting member 50 to be squeezed and deformed, preventing the elastic limiting member 50 from being squeezed, flipped, and detached from the side wall 22, or from arching and displacing the light guide plate 30, thereby losing its function of fixing the light guide plate 30.

[0027] As shown in Figures 2 to 4, in some embodiments, the elastic limiting member 50 further includes a second protrusion 52, which connects to the body 53 and protrudes from the side of the body 53 away from the light guide plate 30 between the two first protrusions 51. Correspondingly, the first wall portion 221 of the sidewall 22 also has a second opening 242, which is located between the two first openings 241. When the elastic limiting member 50 is assembled to the first wall portion 221, the second protrusion 52 of the elastic limiting member 50 engages with the second opening 242. The elastic limiting member 50 can be positioned on the sidewall 22 through the engagement of the second protrusion 52 and the second opening 242 to facilitate assembly. In some embodiments, the area of ​​the second opening 242 is smaller than the area of ​​any one of the first openings 241.

[0028] As shown in Figures 2 to 4, in some embodiments, the second portion 62 of the frame 60 may cover the first opening 241 and the second opening 242 of the sidewall 22. In some embodiments, the first opening 241 of the sidewall 22 is a one-sided open notch structure to facilitate assembly.

[0029] As shown in Figures 2 to 4, in some embodiments, the elastic limiting member 50 further includes a baffle 56 connecting the body 53. When the elastic limiting member 50 is assembled to the first wall portion 221, the baffle 56 extends from the side of the body 53 away from the back plate 21 along a first direction D1 and is located between the third side 73 of the optical film 70 and the first wall portion 221 of the side wall 22, wherein the third side 73 of the optical film 70 corresponds to the first side 31 of the light guide plate 30. With the above configuration, when the display device 15 or the backlight module 19 shakes, the baffle 56 of the elastic limiting member 50 provides a barrier and buffer between the optical film 70 and the side wall 22 of the housing 20, preventing the optical film 70 from directly impacting the side wall 22 of the housing 20 and avoiding abnormal noise.

[0030] As shown in Figures 2 to 4, in some embodiments, the top end of the baffle 56 of the resilient retainer 50 is substantially aligned with the top end of the sidewall 22 of the housing 20 in a direction away from the back plate 21. In some embodiments, one side of the baffle 56 abuts against the sidewall 22, and the other side is recessed relative to the body 53 in a third direction D3, with the third side 73 of the optical film 70 extending at least partially beyond the first side 31 of the light guide plate 30, and the recessed space of the baffle 56 accommodating the third side 73 of the optical film 70.

[0031] Please also refer to Figure 5. Figure 5 is a top view showing the housing 20, light guide plate 30, and elastic limiting member 50 of the backlight module 19 of the display device 15 shown in Figure 1. As shown in Figures 3 to 5, the light guide plate 30 also has a first groove 35, which is located on the first side 31 and engages with the body 53 of the elastic limiting member 50. In this way, the elastic limiting member 50 can limit the light guide plate 30 and prevent the light guide plate 30 from shifting.

[0032] As shown in Figures 3 to 5, in some embodiments, the body 53 of the elastic limiting member 50 has at least one first rounded corner 57, and the first groove 35 of the light guide plate 30 has at least one second rounded corner 37, with the second rounded corner 37 abutting against the first rounded corner 57. In the illustrated embodiment, both corners of the body 53 of the elastic limiting member 50 facing the light guide plate 30 are rounded, and correspondingly, the first groove 35 of the light guide plate 30 has two second rounded corners 37. In some embodiments, in the second direction D2 extending from the first wall portion 221 of the sidewall 22, the maximum width of the first groove 35 of the light guide plate 30 is greater than the maximum width of the body 53 of the elastic limiting member 50. With the above configuration, the problem of gaps between the elastic limiting member 50 and the light guide plate 30 after thermal expansion and contraction can be improved, preventing displacement of the elastic limiting member 50 and the light guide plate 30, and also preventing abnormal noise when the display device 15 or the backlight module 19 shakes.

[0033] As shown in Figure 5, in some embodiments, the light guide plate 30 includes two first epitaxial structures 34 located on the first side 31 and on both sides of the first groove 35. In other words, the two first epitaxial structures 34 define the first groove 35. The second fillet 37 is located inside the first epitaxial structure 34. The second fillet 37 can avoid stress concentration and reduce the risk of breakage of the first epitaxial structure 34.

[0034] As shown in Figure 5, in some embodiments, the two first extensional structures 34 extend into the two first openings 241 of the first wall portion 221, and are located outside the first protrusion 51 of the elastic limiting member 50. In this way, the cooperation between the first extensional structure 34 and the first opening 241 can also limit the light guide plate 30 and prevent the light guide plate 30 from shifting.

[0035] As shown in Figure 5, in some embodiments, each of the two first epitaxial structures 34 has a ramp 36, which is located on the side of the two first epitaxial structures 34 away from the first groove 35. The design of the ramp 36 can improve the structural strength of the first epitaxial structure 34 and reduce the risk of the first epitaxial structure 34 breaking.

[0036] Please refer to Figure 6. Figure 6 is a top view illustrating the housing 20, optical diaphragm 70, and elastic limiting member 50 of the backlight module 19 of the display device 15 shown in Figure 1. As shown, in some embodiments, the optical diaphragm 70 has a second groove 72 located on a third side 73 and engaging with the baffle 56 of the elastic limiting member 50. In this way, the elastic limiting member 50 can limit the optical diaphragm 70 and prevent it from shifting.

[0037] As shown in Figure 6, in some embodiments, the optical film 70 includes two second extensional structures 74 located on the third side 73 and on both sides of the second groove 72; in other words, the two second extensional structures 74 define the second groove 72. The two second extensional structures 74 extend into the two first openings 241 of the first wall portion 221 and are located outside the first protrusion 51 of the elastic limiting member 50. In this way, the cooperation between the second extensional structures 74 and the first openings 241 can also limit the optical film 70, preventing displacement. In some embodiments, each of the two second extensional structures 74 has at least one third fillet 77, which can avoid stress concentration and reduce the risk of breakage of the second extensional structures 74. In some embodiments, the second extensional structures 74 of the optical film 70 are stacked with the first extensional structures 34 of the light guide plate 30.

[0038] Please refer to Figures 7 through 10. Figure 7 is a cross-sectional view showing a backlight module 19A according to another embodiment of this disclosure. Figure 8 is an assembly diagram showing the housing 20A and the elastic limiting member 50A of the backlight module 19A shown in Figure 7. Figure 9 is an exploded view showing the housing 20A and the elastic limiting member 50A of the backlight module 19A shown in Figure 7. Figure 10 is a cross-sectional view showing the housing 20A and the elastic limiting member 50A of the backlight module 19A shown in Figure 8 at the line segment 10-10'.

[0039] As shown in Figures 7 to 10, the main differences between this embodiment and the aforementioned embodiments include: (1) The first wall portion 221A of the sidewall 22A has two first openings 241A and a second opening 242A, the second opening 242A is located between the two first openings 241A, and the area of ​​the second opening 242A is larger than the area of ​​any one of the first openings 241A; (2) The elastic limiting member 50A includes a body 53A, the body 53A is disposed on the first wall portion 221A of the sidewall 22A and the first side of the light guide plate 30A. Between the edges 31A, the body 53A abuts against the first wall portion 221A and includes a plurality of supporting structures 54 abutting against the first side edge 31A of the light guide plate 30A; (3) The elastic limiting member 50A covers the second opening 242A of the side wall 22A. The elastic limiting member 50A also includes two protrusions 51A. The two protrusions 51A are connected to the body 53A and respectively engage with the two first openings 241A of the side wall 22A to position the elastic limiting member 50A on the side wall 22A. In addition, under normal temperature conditions, the elastic limiting member 50A does not have a structure that extends into the second opening 242A. In this way, when the light guide plate 30A expands and squeezes the elastic limiting member 50A due to high temperature, the second opening 242A of the side wall 22A can provide space for the elastic limiting member 50A to be squeezed out and deformed, preventing the elastic limiting member 50A from flipping over and falling off the side wall 22A, or from arching the light guide plate 30A out of place and losing its function of fixing the light guide plate 30A.

[0040] In some embodiments, the backlight module 19A may include a plurality of elastic limiting members 50A disposed on multiple wall portions of the side wall 22A to correspondingly abut against multiple sides of the light guide plate 30A, for example, correspondingly abutting against the first side 31A of the light guide plate 30A away from the light source 40 and the other two sides adjacent to the first side 31A. In some embodiments, the backlight module 19A may include only a single elastic limiting member 50A disposed on one of the wall portions of the side wall 22A (e.g., the first wall portion 221A).

[0041] As shown in Figures 7 to 10, in some embodiments, in a first direction D1 perpendicular to the back plate 21, the height of the second opening 242A of the first wall portion 221A of the sidewall 22A is greater than the height of the body 53A of the elastic limit member 50A and less than the height of the baffle 56 of the elastic limit member 50A, so that the elastic limit member 50A can partially enter the second opening 242A when it is squeezed, and then reliably elastically reset.

[0042] As shown in Figures 7 to 10, the supporting structure 54 is disposed on the side of the body 53A facing the light guide plate 30A, and at least a portion of the supporting structure 54 abuts against the light guide plate 30A, with a groove 55 between any two adjacent supporting structures 54. In other words, the body 53A of the elastic limiting member 50A has a concave-convex structure facing the light guide plate 30A. The first side 31A of the light guide plate 30A abuts against the body 53A of the elastic limiting member 50A, and the first side 31A of the light guide plate 30A can be a straight side or other shapes. In some embodiments, the two outermost supporting structures 54 each have a ramp 58, and the ramp 58 is located outside the supporting structure 54. The above-mentioned structural configuration can increase the deformation degree of the elastic limiting member 50A, thus improving the gap change between the elastic limiting member 50A and the light guide plate 30A caused by thermal expansion and contraction, avoiding displacement of the elastic limiting member 50A and the light guide plate 30A, and also preventing abnormal noise when the display device 15 or the backlight module 19A shakes, which is beneficial for the use of the display device 15 or the backlight module 19A in extreme environments.

[0043] As shown in Figures 7 to 10, in some embodiments, the body 53A of the elastic limiting member 50A includes two first abutment structures 541 and a second abutment structure 542. The two first abutment structures 541 and the second abutment structure 542 protrude from the body 53A, and the second abutment structure 542 is located between the two first abutment structures 541. The body 53A has an outer wall with a first wall portion 221A that abuts against the side wall 22A. The vertical distance between the end of the second abutment structure 542 and the outer wall of the body 53A is distance L2, and the vertical distance between the end of the two first abutment structures 541 and the outer wall of the body 53A is distance L1. Distance L2 is greater than distance L1. In some embodiments, the first support structure 541 has a substantially trapezoidal shape. Specifically, the horizontal cross-section of the first support structure 541 (i.e., the cross-section perpendicular to the first direction D1) is trapezoidal, and the second support structure 542 has a substantially triangular shape. Specifically, the horizontal cross-section of the second support structure 542 is approximately triangular. In some embodiments, the second support structure 542 is a support column on the side of the light guide plate 30A. When the light guide plate 30A is cooled and shrunk at low temperature, the second support structure 542 can continuously abut against and support the light guide plate 30A, preventing the light guide plate 30A from falling off due to increased gaps. When the light guide plate 30A is heated and expands, the second support structure 542 and the first support structure 541 can be compressed and deformed to both sides without arching the light guide plate 30A. In some embodiments, the position of the second support structure 542 corresponds to the second opening 242A of the first wall portion 221A of the sidewall 22A, so the second support structure 542 can deform backward when squeezed by the light guide plate 30A.

[0044] In some embodiments, the structures of the elastic limiting members 50 and 50A disclosed herein can be partially replaced. For example, the elastic limiting member 50 may have two protrusions 51A instead of the first protrusion 51 and the second protrusion 52, and the opening of the first wall portion 221 of the sidewall 22 may also be adjusted accordingly. Alternatively, the elastic limiting member 50 may have two first bearing structures 541 and a second bearing structure 542 instead of the first rounded corner 57 of the body 53, and the first groove 35 and the second rounded corner 37 of the light guide plate 30 may also be adjusted accordingly. In some embodiments, the elastic limiting members 50 and 50A can be used interchangeably in the display device 15, and the sidewall of the housing and the light guide plate may be provided with corresponding structures without affecting the operation of the display device 15.

[0045] In summary, the backlight module disclosed herein includes an elastic limiting member disposed between the light guide plate and the side wall of the housing, the elastic limiting member being used to fix the light guide plate. The above-described structural configuration of the light guide plate, the elastic limiting member, and the side wall helps to improve the reliability of the backlight module, enabling it to be used in environments with large temperature variations and high vibration (e.g., vehicles).

[0046] Although this disclosure has been disclosed above with reference to embodiments, it is not intended to limit this disclosure. Anyone skilled in the art can make various modifications and alterations 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. [Simplified Explanation of the Diagram]

[0047] To make the above and other objects, features, advantages and embodiments of this disclosure more apparent and understandable, the accompanying drawings are explained as follows: Figure 1 is a perspective view of a display device according to one embodiment of this disclosure. Figure 2 is a cross-sectional view of the display device shown in Figure 1 at line segment 2-2'. Figure 3 is an assembly view of the housing and elastic limiting member of the backlight module of the display device shown in Figure 1. Figure 4 is an exploded view of the housing and elastic limiting member of the backlight module of the display device shown in Figure 1. Figure 5 is a top view of the housing, light guide plate and elastic limiting member of the backlight module of the display device shown in Figure 1. Figure 6 is a top view of the housing, optical film and elastic limiting member of the backlight module of the display device shown in Figure 1. Figure 7 is a cross-sectional view of a backlight module according to another embodiment of this disclosure. Figure 8 is an assembly view of the housing and elastic limiting member of the backlight module shown in Figure 7. Figure 9 is an exploded view showing the housing and elastic retaining member of the backlight module shown in Figure 7. Figure 10 is a cross-sectional view showing the housing and elastic retaining member of the backlight module shown in Figure 8 at the mark 10-10'.

Claims

1. A backlight module, comprising: a housing including a back plate and a side wall, the side wall including a first wall portion having two first openings and a second opening, the second opening being located between the two first openings and having an area larger than the area of ​​either of the two first openings; a light guide plate disposed in the housing and having a first side edge corresponding to the first wall portion of the side wall; a light source disposed in the housing and configured to emit light toward the light guide plate; and an elastic limiting member including a body and two protrusions, the body being disposed between the first wall portion of the side wall and the first side edge of the light guide plate, the two protrusions being connected to the body and respectively engaging with the two first openings of the first wall portion.

2. The backlight module as claimed in claim 1, wherein the body of the elastic limiting member includes a plurality of abutment structures disposed on the side of the body facing the light guide plate, and at least a portion of the abutment structures abut against the light guide plate, wherein any two adjacent abutment structures have a groove between them.

3. The backlight module as described in claim 2, wherein the supporting structures include two first supporting structures and a second supporting structure, the second supporting structure being located between the two first supporting structures and protruding more from the body than either of the two first supporting structures.

4. The backlight module as claimed in claim 3, wherein the two first support structures have a substantially trapezoidal shape, the second support structure has a substantially triangular shape, and the position of the second support structure corresponds to the second opening of the first wall portion of the sidewall.

5. The backlight module as claimed in claim 2, wherein the two outermost of the supporting structures each have an inclined surface located outside the two of the supporting structures.

6. The backlight module as claimed in claim 1, further comprising an optical film disposed on the side of the light guide plate away from the back plate and having a third side edge corresponding to the first side edge of the light guide plate, wherein the elastic limiting member further comprises a baffle extending from the side of the body away from the back plate and located between the third side edge of the optical film and the first wall portion of the sidewall.

7. The backlight module as claimed in claim 6, wherein in a direction perpendicular to the first wall portion of the sidewall, the baffle is recessed relative to the body, and the third side of the optical film extends at least partially beyond the first side of the light guide plate.

8. The backlight module as claimed in claim 6, wherein, in a direction perpendicular to the back panel, the height of the second opening of the first wall portion of the sidewall is greater than the height of the body of the elastic limiting member and less than the height of the baffle.

9. A display device, comprising: a display panel; and a backlight module disposed on a back side facing the display panel, and comprising: a housing including a back plate and a side wall, the side wall including a first wall portion having two first openings and a second opening, the second opening being located between the two first openings; a light guide plate disposed in the housing and having a first side edge corresponding to the first wall portion of the side wall; and an optical film disposed on the side of the light guide plate away from the back plate and having a third side edge corresponding to the first side edge of the light guide plate. A light source is disposed in the housing and configured to emit light towards the light guide plate; and an elastic limiting member covers the second opening and includes a body and a baffle. The body is disposed between the first wall portion of the side wall and the first side edge of the light guide plate, and the body abuts against the first wall portion. The baffle extends from the side of the body away from the back plate and is located between the third side edge of the optical film and the first wall portion of the side wall. The body includes a plurality of abutment structures disposed on the side of the body facing the light guide plate and abuts against the light guide plate. A groove is formed between any two adjacent abutment structures.

10. A display device, comprising: a display panel; and a backlight module disposed on a back side facing the display panel, and comprising: a housing including a back plate and a side wall, the side wall including a first wall portion having two first openings and a second opening, the second opening being located between the two first openings; a light guide plate disposed in the housing and having a first side edge corresponding to the first wall portion of the side wall; and an optical film disposed on the side of the light guide plate away from the back plate and having a third side edge corresponding to the first side edge of the light guide plate. A light source is disposed in the housing and configured to emit light toward the light guide plate; and an elastic limiting member includes a body and a baffle. The body is disposed between the first wall portion of the sidewall and the first side edge of the light guide plate, and the baffle extends from the side of the body away from the back plate and is located between the third side edge of the optical film and the first wall portion of the sidewall. In a direction perpendicular to the back plate, the height of the second opening of the first wall portion of the sidewall is greater than the height of the body of the elastic limiting member and less than the height of the baffle.

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