Irregularly-shaped light guide plate designed with groove, backlight module, and display device

Abstract

An irregularly-shaped light guide plate (10) designed with a groove (115), a backlight module (1), and a display device, the backlight module (1) comprising the irregularly-shaped light guide plate (10) designed with the groove (115), and the display device comprising the backlight module (1). The irregularly-shaped light guide plate (10) is provided with a light adjusting unit (12) in the groove (115) located on an opposite light-incident side (113) of a plate body (11), wherein a first reflecting portion (121) of the light adjusting unit (12) is disposed between two second reflecting portions (122), the first reflecting portion (121) and the second reflecting portions (122) having different light adjusting characteristics. When light is incident on the irregularly-shaped light guide plate (10), the first reflecting portion (121) and the second reflecting portions (122) having different light adjusting characteristics, which are arranged on peripheral walls of the groove (115), are used to adjust brightness differences in areas surrounding the groove (115) on the plate body (11), thereby enabling a light source (20) to achieve good light uniformity when incident on the irregularly-shaped light guide plate (10).

Description

Special-shaped light guide plate with groove design, backlight module and display device TECHNICAL FIELD

[0001] The present application relates to a light guide plate, in particular a special-shaped light guide plate suitable for a backlight module in a display device. BACKGROUND

[0002] Currently, most of the display devices are liquid crystal display devices with a rectangular or polygonal geometric shape. The liquid crystal panel of the liquid crystal display device is provided with a backlight source by a backlight module. The light guide plate in the backlight module has a groove at the edge of the plate body, so that the distance between the edge of the plate body and the groove wall and the side light source is not uniform. When the light emitted by the side light source of the backlight module is projected into the light guide plate and reflected, the area adjacent to the groove of the plate body has a higher brightness due to the shorter distance to the side light source.

[0003] In order to ensure the quality of picture display, it is necessary to further overcome the problem of brightness difference caused by the setting of the groove in the light guide plate.

[0004] SUMMARY

[0005] The present application provides a special-shaped light guide plate with groove design, a backlight module and a display device to solve the technical problem of brightness difference in the groove wall area of the light guide plate on the back light side of the existing backlight module.

[0006] In order to achieve the above-mentioned purpose, the present application provides a special-shaped light guide plate with groove design, which comprises:

[0007] a plate body comprising an outlight surface, an inlight side and a back light side located on opposite sides of the outlight surface, and having a groove extending from the back light side to the inlight side; and

[0008] a light adjusting unit arranged in the groove and comprising a first reflection part and two second reflection parts, wherein the first reflection part and the second reflection parts have different light adjusting characteristics, and the first reflection part is arranged between the two second reflection parts.

[0009] In order to achieve the above-mentioned purpose, the present application provides a backlight module, which comprises:

[0010] a special-shaped light guide plate as described above;

[0011] a light source arranged outside the inlight side of the special-shaped light guide plate and capable of projecting light to the inlight side; and

[0012] at least one optical film arranged on the outlight surface of the special-shaped light guide plate.

[0013] To achieve the foregoing purpose, the display device provided by the present application comprises:

[0014] a backlight module as described above; and

[0015] a display panel disposed on the optical film of the backlight module.

[0016] By the profiled light guide plate with the groove design, the backlight module and the display device, the light adjusting unit is disposed on the groove of the light entering side of the plate body of the profiled light guide plate, the light adjusting unit has the first reflection part and the two second reflection parts, the first reflection part is located between the two second reflection parts, and the first reflection part and the second reflection parts have different light adjusting characteristics. When the light is incident on the profiled light guide plate, the first reflection part and the second reflection parts with different light adjusting characteristics are arranged at different positions of the peripheral wall of the groove to provide different light adjusting performance. The light adjusting plate body adjusts the light after the light is incident on the plate body. The light source is incident on the profiled light guide plate to achieve good light uniformity.

[0017] The present application further utilizes that the parallel reflectivity of the first reflection part is greater than the parallel reflectivity of the second reflection part, or the light absorption rate of the first reflection part is greater than the light absorption rate of the second reflection part. The first reflection part and the second reflection part arranged on the peripheral wall of the groove utilize the difference of the parallel reflectivity or the difference of the light absorption rate to adjust the brightness of different areas around the groove of the plate body.

[0018] The present application further utilizes that the light entering side and the two side edges of the plate body are each provided with a reflection sheet. The light reflected back into the plate body by the reflection sheet arranged on the light entering side and the two side edges of the plate body improves the light energy utilization rate of the profiled light guide plate. At the same time, the reflection sheet arranged on the light entering side and the two side edges of the plate body assists the light adjusting unit arranged on the peripheral wall of the groove of the plate body to adjust the light adjusting performance of the peripheral area of the groove, and improves the light brightness and uniformity of the profiled light guide plate.

[0019] The present application further defines that the first distance between the light entering side and the light entering side is provided with a first distance, the second distance between the groove and the light entering side is provided with a second distance, the first ratio of the second distance to the first distance is controlled to be between 0.15 and 0.5 (including the end point value), or the light entering side is provided with a first width, the groove is provided with a second width, the second ratio of the second width to the first width is controlled to be between 0.25 and 0.7 (including the end point value), which reduces the influence of the groove of the profiled light guide plate on the uniformity of the light emitting surface on the light entering side, and further improves the light adjusting performance of the light adjusting unit arranged on the groove of the profiled light guide plate, and improves the light brightness and uniformity of the profiled light guide plate. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic view of an embodiment of the profiled light guide plate of the present application.

[0021] Figure 2 is a partial enlarged view of the embodiment of the profiled light guide plate shown in Figure 1.

[0022] Figure 3 is a schematic view of a cross-sectional view of the profiled light guide plate shown in Figure 1 at the location of the section line A-A.

[0023] Figure 4 is a schematic view of the embodiment of the profiled light guide plate of the present application indicating a first distance and a second distance.

[0024] Figure 5 is a schematic view of the embodiment of the profiled light guide plate of the present application indicating a first width and a second width.

[0025] Figure 6 is another schematic view of the embodiment of the profiled light guide plate of the present application indicating a first width and a second width.

[0026] Figure 7 is a schematic view of an embodiment of the backlight module of the present application.

[0027] Figure 8 is a schematic view of an embodiment of the display device of the present application. DETAILED DESCRIPTION

[0028] In accordance with the content described in the foregoing summary of the present application, the present application includes a profiled light guide plate having a groove design, a backlight module, and a display device, the specific configurations of the profiled light guide plate, the backlight module, and the display device are described below with reference to the accompanying drawings.

[0029] As shown in Figures 1-3, an embodiment of the profiled light guide plate 10 having a groove design of the present application is disclosed, the profiled light guide plate 10 includes a plate body 11 and a light adjusting unit 12.

[0030] As shown in Figures 1 and 3, the plate body 11 includes a light exit surface 111, and a light entrance side 112 and a reverse light entrance side 113 located on opposite sides of the light exit surface 111, the plate body 11 also has two side edges 114 between the light entrance side 112 and the reverse light entrance side 113, and a back side 116 located on the other side of the light exit surface 111, the plate body 11 has a groove 115 extending from the reverse light entrance side 113 toward the light entrance side 112, the groove 115 penetrates from the light exit surface 111 to the back side 116, a space is provided by the groove 115 at the plate body 11 adjacent to the reverse light entrance side 113 to accommodate external elements, such as image capturing elements, sensing elements, or elements for human-computer interaction purposes, etc.

[0031] The light adjusting unit 12 is arranged to reduce the difference between light and dark in the peripheral area of the recess 115 of the plate body 11. As shown in FIG. 2, the light adjusting unit 12 is arranged in the recess 115 of the plate body 11 and includes a first reflection part 121 and two second reflection parts 122. The first reflection part 121 is arranged between the two second reflection parts 122. The first reflection part 121 and the two second reflection parts 122 can be independent parts or can be integrated into one part. The first reflection part 121 and the second reflection parts 122 have different light adjusting properties. The first reflection part 121 and the second reflection parts 122 are arranged in different positions of the peripheral wall of the recess 115 of the plate body 11 to provide different light adjusting properties, thereby effectively reducing the difference between light and dark in the peripheral area of the recess 115 of the plate body 11.

[0032] As shown in FIGS. 1-3, in general, the light incident from the light-incident side 112 of the plate body 11 of the irregular light guide plate 10 travels toward the light-incident side 113 and is guided to the light- emitting surface 111 by total reflection of the plate body 11. The recess 115 is arranged at the light-incident side 113 of the plate body 11 to change the total reflection of the light by the originally rectangular plate body 11. Before the light adjusting unit 12 is arranged in the recess 115, the peripheral area of the plate body 11 adjacent to the recess 115 has a higher brightness due to the shorter distance from the light-incident side 112.

[0033] The shape and size of the recess 115 are set according to the product requirements. As shown in the embodiment of FIG. 2, the recess 115 includes a bottom wall 1151 and two side walls 1152 on both sides of the bottom wall 1151, wherein the bottom wall 1151 faces the light-in side 112. Based on the position of the bottom wall 1151 on the recess 115 facing the light-in side 112, the distance from the bottom wall 1151 to the light-in side 112 is less than the distance from the light-out side 113 to the light-in side 112. In terms of the peripheral wall of the recess 115, because the distance from the bottom wall 1151 to the light-in side 112 is closer, the brightness of the area adjacent to the bottom wall 1151 of the plate body 11 after light-in is greater than the brightness of the area adjacent to the side wall 1152 of the plate body 11. The bottom wall 1151 and the side wall 1152 are both straight wall surfaces, and the included angle θ between the bottom wall 1151 and the adjacent side wall 1152 can be a right angle or an obtuse angle, i.e., the included angle θ between the bottom wall 1151 and the adjacent side wall 1152 is not an acute angle. In this way, the light from the light-in side 112 can directly and unobstructed contact the light-out side 113, the bottom wall 1151 and the side wall 1152 of the recess 115; on the contrary, if the included angle θ is an acute angle, it can occur that the light can only straightly advance to produce a dead angle that cannot transmit uniform light, at which time a very obvious dark corner of the plate body 11 of the special-shaped light guide plate 10 will occur.

[0034] As shown in FIG. 2, in the present embodiment, the first reflection part 121 is located on the bottom wall 1151 of the recess 115, and the two second reflection parts 122 are respectively located on the two side walls 1152. By using the parallel reflection characteristics or the light absorption characteristics of the light adjusting unit 12 on the peripheral wall of the recess 115 of the plate body 11, the light-dark difference of the peripheral area of the recess 115 is adjusted, and the expected light uniformity is achieved. In the present embodiment, in order to effectively improve the light-dark difference of different parts of the recess 115 after the plate body 11 is lighted in, the first reflection part 121 and the second reflection part 122 with different light adjusting characteristics in the light adjusting unit 12 of the recess 115 can be set as the parallel reflectivity of the first reflection part 121 being greater than the parallel reflectivity of the second reflection part 122. Alternatively, the light absorption rate of the first reflection part 121 is set to be greater than the light absorption rate of the second reflection part 122.

[0035] For example, when the parallel reflectivity of the first reflective portion 121 is greater than that of the second reflective portion 122, the second reflective portion 122 can be a white reflective sheet, and the first reflective portion 121 can be a silver reflective sheet with higher parallel reflectivity. The first reflective portion 121 is located on the groove bottom wall 1151 of the groove 115 to provide higher parallel reflection performance for light from the light-in side 112, to properly reflect and adjust the angle of light projected to the groove bottom wall 1151, and to adjust the light-dark difference of the surrounding area of the groove 115. When the light absorption rate of the first reflective portion 121 is greater than that of the second reflective portion 122, the second reflective portion 122 can be a white reflective sheet, and the first reflective portion 121 can be a gray reflective sheet with higher light absorption rate. The gray reflective sheet can be a reflective surface with any gray value between white and black in a gray-scale image. The first reflective portion 121 is located on the groove bottom wall 1151 of the groove 115 to provide higher light absorption performance for light from the light-in side 112, to adjust the light-dark difference of the surrounding area of the groove 115.

[0036] As shown in FIGS. 1 and 2, the profiled light guide plate 10 can further have a reflective sheet 123 on each of the light-in side 113 and the two side edges 114 of the plate body 11. The reflective sheet 123 is configured to re-reflect light projected to the light-in side 113 and the two side edges 114 back into the plate body 11, to improve the light energy utilization rate of the profiled light guide plate 10. The reflective sheet 123 on each of the light-in side 113 and the two side edges 114 of the plate body 11 can assist the light adjustment unit 12 arranged on the surrounding wall of the groove 115 of the plate body 11 to adjust the light adjustment performance of the surrounding area of the groove 115, to improve the light brightness and uniformity of the profiled light guide plate 10.

[0037] As shown in FIGS. 1 and 2, the reflective sheet 123 on each of the light-in side 113 and the two side edges 114 of the plate body 11 can be a silver reflective sheet, a white reflective sheet, or other reflective sheet with higher reflectivity. In this embodiment, the light adjustment performance of the reflective sheet 123 is the same as that of the second reflective portion 122. When the second reflective portion 122 is a white reflective sheet, the reflective sheet 123 is also a white reflective sheet, but is not limited thereto.

[0038] In the foregoing, the present application selects the light adjustment characteristics of the reflective sheet 123 to be the same as those of the second reflective portion 122, with the main purpose of ensuring that the relative irregular light guide plate 10 located outside the groove bottom wall 1151 of the groove 115, such as the groove side wall 1152, the light-incoming side 113, and the side edge 114, can all be treated with the same optical characteristics of the reflective sheet 123 to ensure the brightness consistency of the light-outcoming surface 111 of the irregular light guide plate 10 in other areas. Therefore, under the same light reflection or light absorption conditions, only the light of the groove bottom wall 1151 is adjusted by the first reflective portion 121, and no excessive trial and error is required to achieve the result of uniform light-outcoming of the entire light-outcoming surface 111.

[0039] In terms of product application, the irregular light guide plate of the present application can be applied to products such as mobile phones, tablets, computers, displays, or vehicle-mounted products. For example, due to the human-machine interaction process between the car and the driver, the sensor or camera module provided in the display in front of the driver's seat is required to perceive the driver's designation or information, so the size of the groove of the irregular light guide plate in the vehicle-mounted product is relatively larger than that of the irregular light guide plate in the mobile phone. Referring to FIG. 4, in an embodiment in which the irregular light guide plate of the present application is applied to a vehicle-mounted product, the light-incoming side 113 to the light-outcoming side 112 of the plate body 11 has a first distance D1, and the groove 115 to the light-incoming side 113 has a second distance D2, and the first ratio of the second distance D2 to the first distance D1 is between 0.15 and 0.5, inclusive. In more detail, the second distance D2 refers to the distance from the groove bottom wall 1151 of the groove 115 to the light-incoming side 113.

[0040] Referring to FIGS. 5 and 6, in other embodiments of the irregular light guide plate of the present application, the light-incoming side 113 of the plate body 11 has a first width W1, and the groove 115 has a second width W2, and the second ratio of the second width W2 to the first width W1 is between 0.25 and 0.7, inclusive. The first width W1 of the light-incoming side 113 can also refer to the distance between the two side edges 114. The second width W2 of the groove 115 can be the width of the groove bottom wall 1151 of the groove 115, or the opening width of the entire groove 115, and is not limited to the width of the groove bottom wall 1151. In more detail, since vehicle-mounted products usually have the requirements of high brightness and low energy consumption, when the irregular light guide plate 10 disclosed in the present application is provided with the light adjustment unit 12 in the groove 115, it can ensure that the light can contact the first reflective portion 121, the second reflective portion 122, and the reflective sheet 123 with different light adjustment characteristics in different areas, and then be out of the light guide plate 10, which not only solves the problem of bright spray in the area close to the groove bottom wall 1151 of the groove 115, but also meets the requirements of uniformity and low energy consumption of vehicle-mounted display devices of various types.

[0041] In another aspect, in the backlight module of a small-sized mobile phone, in order to set the front lens, an opening is set in the light guide plate, the ratio of the distance (i.e. length) from the opening to the light-in side to the distance (i.e. length) from the light-in side to the light-out side of the light guide plate is usually less than 0.2, or the ratio of the width between the two side edges of the light guide plate to the diameter of the opening is less than 0.07. The light guide plate of the small-sized mobile phone meeting the above specifications usually selects the way of not attaching any reflective sheet, so that the light directly passes through the groove without being reflected back into the light guide plate, to achieve the uniformity requirement of the light-out surface.

[0042] As shown in FIG. 7, an embodiment of the backlight module 1 of the present application is disclosed, and the composition and structure of the backlight module 1 of the present application includes a profiled light guide plate 10, a light source 20, and at least one optical film 30. The specific shape and structure of the profiled light guide plate 10 are as described above, and will not be repeated here.

[0043] As shown in FIG. 7, the light source 20 is arranged outside the light-in side 112 of the profiled light guide plate 10 and can project light onto the light-in side 112 of the plate body 11, so that the incident light is guided by the total reflection of light of the plate body 11 and uniformly out of the light-out surface 111 of the plate body 11. The light source 20 can be selected as an LED light bar including multiple LED light-emitting elements, so as to have the advantages of low power consumption and long service life.

[0044] As shown in FIG. 7, the optical film 30 can be one or more and has specific optical properties. Generally, the optical film 30 can be selected as a diffusion sheet having light diffusion properties, a brightness enhancement film having brightness enhancement properties, a prism film having light guiding and turning properties, etc. The number of the optical film 30 and the selection of its optical properties are set according to the use requirements of the backlight module 1. The optical film 30 is arranged on the light-out surface 111 of the profiled light guide plate 10, and the shape of the optical film 30 matches the shape of the plate body 11 of the profiled light guide plate 10 having the groove 115. After the light emitted by the light source 20 is guided by the profiled light guide plate 10 to change the direction of the light, the light is diffused and brightened by the optical film 30, so as to improve the brightness and uniformity of the light-out of the backlight module 1.

[0045] As shown in FIG. 8, an embodiment of the display device of the present application is disclosed, and the constituent structure of the display device of the present application includes a backlight module 1 and a display panel 4 disposed on the optical film 30 of the backlight module 1. The display panel 4 is a liquid crystal panel and is provided with a backlight source 20 by the backlight module 1. The shape of the display panel 4 matches the shape of the irregular light guide plate 10, and the display panel 4 has a notch 40 matching the groove 115 of the irregular light guide plate 10. The display device can be equipped with an image capturing element, a sensing element, or a combination of the image capturing element and the sensing element in the space combined by the corresponding groove 115 of the irregular light guide plate 10 and the notch 40 of the display panel 4. In this way, the overall modular structure facilitates the display device including the image capturing element, the sensing element, or the combination thereof to be installed in the instrument area of the motor vehicle and connected to the vehicle-mounted computer. The present application can also be widely applied to various types of side-entry light type vehicle-mounted display devices and can be widely adapted to electric vehicles and intelligent driving cabins. The display device of the present application can meet the installation requirements of many human-computer interaction external elements of electric vehicles and intelligent driving cabins.

[0046]

Symbol Description

[0047] 1: Backlight module

[0048] 10: Irregular light guide plate

[0049] 11: Plate body

[0050] 111: Light exit surface

[0051] 112: Light entrance side

[0052] 113: Light entrance side

[0053] 114: Side

[0054] 115: Groove

[0055] 1151: Groove bottom wall

[0056] 1152: Groove side wall

[0057] 116: Back side

[0058] θ: Angle between groove bottom wall and groove side wall

[0059] 12: Light adjustment unit

[0060] 121: First reflection part

[0061] 122: Second reflection part

[0062] 123: Reflection sheet

[0063] 20: Light source

[0064] 30: optical film

[0065] : display panel

[0066] 40: notch

[0067] D1: first distance from the anti-light-incident side to the light-incident side

[0068] D2: second distance from the groove to the anti-light-incident side

[0069] W1: first width of the anti-light-incident side

[0070] W2: second width of the groove

Claims

1. A custom-shaped light guide plate with a groove design, comprising: The plate includes a light-emitting surface, and light-incident side and light-reflecting side located on opposite sides of the light-emitting surface, and has a groove extending from the light-reflecting side toward the light-incident side. as well as A dimming unit is disposed in the groove and includes a first reflective part and two second reflective parts, wherein the first reflective part and the second reflective parts have different dimming characteristics, and the first reflective part is disposed between the two second reflective parts.

2. The irregularly shaped light guide plate with a groove design as described in claim 1, wherein, The parallel reflectivity of the first reflective part is greater than that of the second reflective part.

3. The irregularly shaped light guide plate with a groove design as described in claim 1, wherein, The light absorption rate of the first reflective part is greater than that of the second reflective part.

4. The irregularly shaped light guide plate with a groove design as described in claim 1, wherein, The groove includes a bottom wall and two side walls located on both sides of the bottom wall. Both the bottom wall and the side walls are straight surfaces. The first reflective part is located on the bottom wall and the second reflective part is located on the side walls.

5. The irregularly shaped light guide plate with a groove design as described in claim 4, wherein, The angle between the bottom wall of the trough and the adjacent side wall of the trough is not an acute angle.

6. The irregularly shaped light guide plate with a groove design as described in claim 1, wherein, The plate also includes two sides located between the light-incident side and the light-reflecting side. Each of the light-reflecting side and the two sides is provided with a reflective sheet. The dimming characteristics of the reflective sheet are the same as those of the second reflective part.

7. The irregularly shaped light guide plate with a groove design as described in claim 1, wherein, There is a first distance between the light-reflecting side and the light-receiving side, and there is a second distance between the groove and the light-reflecting side. The first ratio of the second distance to the first distance is between 0.15 and 0.5, including the endpoint values.

8. The irregularly shaped light guide plate with a groove design as described in claim 1 or 7, wherein, The reflected light side has a first width, and the groove has a second width, the second width being a second ratio of the first width to a second width between 0.25 and 0.7, including the endpoint values.

9. A backlight module, comprising: The irregularly shaped light guide plate as described in any one of claims 1 to 8; The light source is located outside the light-incident side of the irregularly shaped light guide plate and can project light onto the light-incident side; as well as At least one optical film is disposed on the light-emitting surface of the irregularly shaped light guide plate.

10. A display device comprising: The backlight module as described in claim 9; as well as The display panel is disposed on the optical film of the backlight module.

11. The display device as claimed in claim 10, wherein, The display panel has a notch that matches the groove of the irregular light guide plate, and the notch and the groove can accommodate an image capturing element, a sensing element, or a combination thereof.

Images