JP3216059U - Light guide plate, backlight module, and display device - Google Patents

Abstract

A light guide plate, a backlight module, and a display device are provided. Both a backlight module and a display device include a light guide plate 10A. In the light guide plate 10A, a plurality of light guide microstructures 12A including a circular plane 121A and an inclined circumferential surface 122A are formed on the reflection surface 112A of the light guide plate main body 11A, and the circular plane 121A is parallel to the reflection surface 112A. The inclined circumferential surface 122A extends from the circumference of the circular plane 121A to the reflective surface, and thereby the flat circular plane 121A of the light guide microstructure 12A. The surrounding inclined circumferential surface 122A converges light rays, reduces stray light, and improves the luminance of the emitted light after the light source passes through the light guide plate 10A. [Selection] Figure 10

Description

  The present invention relates to a light guide member and its application, and more particularly to a light guide plate, a backlight module, and a display device.

  A display panel of a display device such as a liquid crystal display generally has to provide a necessary backlight using a backlight module. The structure of the currently known backlight module is such that a light source is installed outside the light incident surface of the light guide plate, and one or more optical films are installed outside the light exit surface of the light guide plate. The light is uniformly dispersed after passing through the light guide plate, and the light emitted from the light exit surface of the light guide plate is further diffused and reflected and brightened by the optical film, thereby providing a backlight with uniform brightness to the display panel. provide.

  The structure of the light guide plate mainly includes a rectangular flat light guide plate main body, and the light guide plate main body emits light in a direction shifted by 90 degrees from the incident direction in order to improve diffusion and reflection of incident light. Since the light guide plate has a plurality of light guide microstructures formed on the reflective surface of the light guide plate body, the light guide plate is used to direct light incident on the light guide plate toward the light exit surface. Reflect.

  In the conventional light guide plate structure, as shown in FIG. 15, the bottom surface of the light guide fine structure 42 formed on the reflection surface 41 of the light guide plate 40 is formed in a full arc-shaped curved surface, and the light incident surface 43 of the light guide plate 40. When the light beam incident via the light guide microstructure 42 passes through the light guide microstructure 42, the light beam is likely to be directly emitted from an arcuate curved surface facing away from the light incident surface 43 of the light guide microstructure 42, but is directed to the light emission surface 44. The light beam cannot be reflected in the direction, and the light rays generate a relatively large amount of stray light after passing through the light guide plate 40, thereby reducing the effective light passing through the light exit surface 44 of the light guide plate 40 and the brightness of the emitted light. Reduce.

  An object of the present invention is to provide a light guide plate, a backlight module, and a display device for solving the problem that a conventional light guide plate generates a relatively large amount of stray light and the problem of reducing luminance.

  In order to achieve the above object, the light guide plate of the present invention includes a light guide plate body including a light exit surface, a reflection surface, and an incident light side surface, and a plurality of light guide microstructures formed on the reflection surface of the light guide plate body. The light exit surface and the reflective surface are located on opposite sides of the light guide plate body, the incident light side surfaces are located on the sides of the light guide plate body, and the light guide microstructure is a circular plane and Including the inclined circumferential surface, the circular plane is parallel to the reflecting surface and forms a step with respect to the reflecting surface, and the inclined circumferential surface extends from the periphery of the circular plane to the reflecting surface.

  In the light guide plate as described above, the light guide microstructure protrudes from the reflection surface, the light guide microstructure includes a center line orthogonal to the reflection surface, and the circular plane of the light guide microstructure is located outside the reflection surface. Yes.

  In the light guide plate as described above, the light guide microstructure protrudes from the reflection surface and defines a bottom plane on the reflection surface, and the circular plane of the light guide microstructure is located outside the reflection surface. The structure includes a center line, the center line is inclined from the center of the circular plane toward the incident light side surface and extends to the center of the bottom plane, and the center line and the normal passing through the center of the circular plane are acute angles Make a depression.

  In the light guide plate as described above, the light guide microstructure protrudes from the reflection surface, the circular plane of the light guide microstructure is located outside the reflection surface, the light guide microstructure includes a center line, and the light guide microstructure The inclined circumferential surface of the structure includes a first plane wire facing the incident light side surface and a second plane wire facing away from the incident light side surface, and the first plane wire and the second plane wire are each along the incident light direction of the center line. The angle of the outer angle formed with respect to the reflecting surface of the first plane wire is different from the angle of the outer angle formed with respect to the reflecting surface of the second plane wire. Are formed into an asymmetric structure.

  In the light guide plate as described above, the light guide microstructure is recessed from the reflection surface to the inside, the light guide microstructure includes a center line orthogonal to the reflection surface, and the circular plane of the light guide microstructure is located inside the reflection surface. doing.

  In the light guide plate as described above, the light guide microstructure is recessed from the reflection surface to the inside to define an opening in the reflection surface, and the circular plane of the light guide microstructure is located inside the reflection surface. The optical fine structure includes a center line, and the center line is inclined from the center of the circular plane toward the incident light side and extends to the center of the aperture, and passes through the center line and the center of the circular plane. The line forms an acute angle that is an acute angle.

  In the light guide plate as described above, the light guide microstructure is recessed from the reflection surface to the inside, the circular plane of the light guide microstructure is located inside the reflection surface, the light guide microstructure includes the center line, and is guided. The inclined circumferential surface of the optical fine structure includes a first plane wire facing the incident light side surface and a second plane wire facing away from the incident light side surface, and the first plane wire and the second plane wire are respectively incident light directions of the center line. The angle of the inner angle formed with respect to the reflective surface of the first plane wire is different from the angle of the inner angle formed with respect to the reflective surface of the second plane wire. The microstructure is formed into an asymmetric structure.

  In the light guide plate as described above, a plurality of light emission fine structures are formed on the light emission surface of the light guide plate.

  In order to achieve the above object, a backlight module of the present invention includes a light guide plate as described above, at least one optical film installed outside a light exit surface of the light guide plate, and an incident light side surface of the light guide plate. And a light source whose light emission direction faces the side surface of the incident light.

  In order to achieve the above object, a display device of the present invention includes a backlight module as described above, and a display panel provided outside an optical film of the backlight module.

The present invention mainly has the following advantages.
1. Concentrate light and improve brightness. The light guide plate of the present invention mainly uses a plurality of light guide microstructures formed on a reflection surface, and each light guide microstructure includes a circular plane and an inclined circumferential surface extending from the periphery of the circle plane to the reflection surface. After the light beam is incident from the incident light side surface of the light guide plate, it is reflected by bringing it into contact with the circular plane, and then some of the reflected light beams are directed in the direction toward the direct light exit surface. In other words, the reflected light rays of the other parts contact the inclined circumferential surface around the circular system plane, and after being re-reflected, change the direction toward the light exit surface, thereby converging the light, and the full width at half maximum (Fullwidth full height maximum, (Abbreviated as FWHM) can be further reduced. In this way, the light guide plate can converge light rays through a plurality of special light guide microstructures and reduce stray light, thus increasing the effective light emitted through the light exit surface of the light guide plate. The brightness of the emitted light can be improved.
2. Make the light guide plate easier to release. As described above, the light guide plate of the present invention mainly uses a plurality of light guide microstructures formed on the reflection surface, and each light guide microstructure is inclined to the reflection surface from the periphery of the circular plane and the periphery of the circular plane. When the light guide plate of the present invention is molded and manufactured by this structure, the mold release is compared with the bottom structure of the whole arc-shaped curved surface in the light guide fine structure of the conventional light guide plate. It has the advantage of being easy to do.

It is a top view of Example 1 of the light-guide plate concerning this invention. It is the perspective view which looked at the light guide fine structure in Example 1 of the light guide plate shown by FIG. 1 from the bottom. It is a top view of Example 2 of the light-guide plate concerning this invention. It is the perspective view which looked at the light guide fine structure in Example 2 of the light guide plate shown by FIG. 2 from the bottom. It is a top view of Example 3 of the light-guide plate concerning this invention. It is a top view of Example 4 of the light-guide plate concerning this invention. It is a top view of Example 5 of the light-guide plate concerning this invention. It is a top view of Example 6 of the light-guide plate concerning this invention. It is a top view of the Example of the backlight module concerning this invention. It is a schematic diagram in which incident light is reflected by Example 1 of the light-guide plate of this invention. It is a schematic diagram in which incident light is reflected by Example 3 of the light-guide plate of this invention. It is a schematic diagram in which incident light is reflected by Example 4 of the light-guide plate of this invention. It is a schematic diagram in which incident light is reflected by Example 6 of the light-guide plate of this invention. It is a top view of the Example of the display apparatus concerning this invention. It is a schematic diagram in which incident light is reflected by a well-known light-guide plate.

  The present invention relates to a light guide plate, a backlight module, and a display device. 1, 3 and 5 to 8 show a plurality of embodiments of the light guide plate according to the present invention. As shown in the figure, the light guide plates 10A to 10F include light guide plate bodies 11A to 11F and a plurality of light guide microstructures 12A to 12F.

  In various embodiments as shown in FIGS. 1, 3, and 5-8, the light guide plate body 11 includes light exit surfaces 111A-111F, reflection surfaces 112A-112F, and incident light side surfaces 113A-113F. The surfaces 111A to 111F and the reflecting surfaces 112A to 112F are located on opposite sides of the light guide plate bodies 11A to 11F, respectively, and the incident light side surfaces 113A to 113F are located on the sides of the light guide plate bodies 11A to 11F. A plurality of light emission microstructures (not shown) such as a strip-like microstructure perpendicular to the incident light side surfaces 113A to 113F are further formed on the 10F light emission surfaces 111A to 111F.

  In various embodiments as shown in FIGS. 1, 3 and 5-8, the plurality of light guide microstructures 12A-12F are formed on the reflective surfaces 112A-112F of the light guide plate bodies 11A-11F, and the plurality of light guide microstructures 12A-12F are formed. The optical microstructures 12A to 12F extend in a direction substantially perpendicular to the incident light side surfaces 113A to 113F. Thereby, the light directionality of the light guide plates 10A to 10F can be adjusted by the plurality of light guide microstructures 12A to 12F installed on the reflection surfaces 112A to 112F. The light guide microstructures 12A to 12C may be protrusions protruding from the reflective surfaces 112A to 112C, or the light guide microstructures 12D to 12F may be concave grooves recessed to the reflective surfaces 112D to 112F. The shape and size of the light guiding microstructures 12A to 12F and the density and the like installed on the reflecting surfaces 112A to 112F may be arranged according to the distance to the incident light side surfaces 113A to 113F or the requirements of the optical characteristics of different products. it can.

  In various embodiments as shown in FIGS. 1-8, the light guide microstructures 12A-12F include circular planes 121A-121F and inclined circumferential surfaces 122A-122F. As shown in FIGS. 2 and 4, the circular planes 121 </ b> A to 121 </ b> F indicate circular planes, elliptical planes, or the like. The circular planes 121A to 121F are parallel to the reflecting surfaces 112A to 112F, and form a step h with respect to the reflecting surfaces 112A to 112F. In the embodiment of the present invention, the step height h of the circular planes 121A to 121F with respect to the reflecting surfaces 112A to 112F is about 1 μm to 3 μm. The inclined circumferential surfaces 122A to 122F extend from the periphery of the circular planes 121A to 121F to the reflecting surfaces 112A to 112F. In this embodiment, the inner angle between the inclined circumferential surfaces 122A to 122F and the circular planes 121A to 121F is about 130 to 150 degrees.

  In the first embodiment as shown in FIGS. 1 and 2, the light guide microstructure 12A protrudes from the reflecting surface 112A, and the light guide microstructure 12A is a regular frustoconical protrusion. The light guide microstructure 12A includes a center line 120A orthogonal to the reflective surface 112A, and the circular planar surface 121A of the light guide microstructure 12A is located outside the reflective surface 112A.

  In the second embodiment as shown in FIGS. 3 and 4, the light guide microstructure 12B protrudes from the reflection surface 112B and defines a bottom plane 123B at the reflection surface 112B, and the circular planar surface 121B of the light guide microstructure 12B reflects. It is located outside the surface 112B. The light guide microstructure 12B is an oblique frustoconical protrusion. The light guide microstructure 12B includes a center line 120B. The center line 120B extends from the center of the circular plane 121B toward the incident light side surface 113B and extends to the center of the bottom plane 123B, and the center line 120B and the circular plane 121B. And the normal line L1 passing through the center of the angle is an acute angle θ1.

  In Example 3 as shown in FIG. 5, the light guiding microstructure 12C protrudes from the reflecting surface 112C, and the circular plane 121C of the light guiding microstructure 12C is located outside the reflecting surface 112C. Is an oblique protrusion. The light guide microstructure 12C includes a center line 120C, and the inclined circumferential surface 122C of the light guide microstructure 12C includes a first plane wire 124C facing the incident light side surface 113C and a second plane wire 125C facing back to the incident light side surface 113C. The first plane wire 124C and the second plane wire 125C are located on opposite sides of the center line 120C along the incident light direction, and are external angles formed with respect to the reflecting surface 112C of the first plane wire 124C. The angle α1 is different from the angle α2 formed with respect to the reflecting surface 112C of the second plane wire 125C, and the light guide microstructure 12C is formed in an asymmetric structure.

  In Example 4 as shown in FIG. 6, the light guide microstructure 12D may be recessed from the reflecting surface 112D to the inside, and the light guide microstructure 12D may be a concave truncated conical groove. The light guide microstructure 12D includes a center line 120D orthogonal to the reflective surface 112D. The circular plane 121D of the light guide microstructure 12D is located inside the reflection surface 112D.

  In Example 5 as shown in FIG. 7, the light guide microstructure 12E is recessed from the reflective surface 112E to define an opening 126E in the reflective surface 112E, and the circular planar surface 121E of the light guide microstructure 12E is a reflective surface. It is located inside 112E. The light guide microstructure 12E may be an oblique frustoconical concave groove. The light guide microstructure 12E includes a center line 120E. The center line 120E is inclined from the center of the circular plane 121E toward the incident light side surface 113E and extends to the center of the opening 126E. A normal angle L2 passing through the center of the plane 121E forms an acute angle θ2.

  In Example 6 as shown in FIG. 8, the light guide microstructure 12F is recessed from the reflective surface 112F to the inside, and the circular plane 121F of the light guide microstructure 12F is located inside the reflective surface 112F. The light guide microstructure 12F is an oblique groove. The light guide microstructure 12 includes a center line 120, and the inclined circumferential surface 122F of the light guide microstructure 12F includes a first plane wire 124F facing the incident light side surface 113F and a second plane wire 125F facing away from the incident light side surface 113F. The first plane wire 124F and the second plane wire 125F are located on opposite sides of the center line 120F along the incident light direction, and are formed at the inner angles formed with respect to the reflecting surface 112F of the first plane wire 124F. The angle of β1 is different from the angle of the internal angle β2 formed with respect to the reflecting surface 112F of the second plane wire 125F, and the light guide microstructure 12F is formed in an asymmetric structure.

  As shown in FIG. 9, the backlight module 1 of the present invention includes a light guide plate 10 </ b> A, at least one optical film 20, and a light source 30. Since the structure of the light guide plate 10A is the same as the structure of the light guide plates 10A to 10F shown in the various embodiments described above, description thereof is omitted here. The optical film 20 is installed outside the light exit surface 111A of the light guide plate 10A. When the number of the optical films 20 is plural, the plural optical films 20 are sequentially arranged so as to be stacked on the outer side of the light exit surface 111A of the light guide plate 10A. The light source 30 is provided outside the incident light side surface 113A of the light guide plate 10A, the light emission direction of the light source 30 is directed to the incident light side surface 113A, and the light from the light source 30 is incident through the incident light side surface 113A of the light guide plate 10A. Then, the light can be uniformly diffused and changed in direction by the light guide plate 10A, and subsequently emitted from the light exit surface 111A of the light guide plate 10A so as to be uniformly dispersed.

  In various embodiments of the light guide plates 10A to 10F, when the light guide microstructures 12A and 12D are regular frustoconical protrusions or regular frustoconical grooves, light from the light source is incident on the light guide plates 10A and 10D. As shown in FIGS. 10 and 12, the incident light rays are incident on the optical side surfaces 113A and 113D and reflected in contact with the circular planes 121A and 121D in the process of traveling in the light guide plates 10A and 10D. Thus, some of the reflected light beams change their direction directly toward the light exit surfaces 111A and 111D, and the other reflected light beams come into contact with the inclined circumferential surfaces 122A and 122D around the circular planes 121A and 121D. After being reflected, the direction is changed to the direction toward the light exit surfaces 111A and 111D, the light rays are converged, and the full width at half maximum (Full width at half maximum, FWHM) Referred) can be further reduced. In this way, since the light guide plates 10A and 10D can converge the light rays through the plurality of special light guide microstructures 12A and 12D and reduce stray light, the light exit surfaces 111A of the light guide plates 10A and 10D can be reduced. The effective light emitted via 111D can be increased, and the brightness of the emitted light can be improved.

  When the light guide microstructures 12B, 12C, 12E, and 12F of the light guide plates 10B, 10C, 10E, and 10F are oblique protrusions or oblique concave grooves, the light guide plates 10C and 10F illustrated in FIGS. In the process in which the incident light beam travels in the light guide plates 10C and 10F, as shown in FIGS. 11 and 13, the light beam is reflected by contacting the circular planes 121C and 121F. Changes the direction directly toward the light exit surfaces 111C and 111F, and the reflected light rays of the other parts come into contact with the inclined circumferential surfaces 122C and 122F around the circular planes 121C and 121F, and are reflected again after being reflected again. The direction is changed in the direction toward 111C and 111F to converge the light beam. Here, the traveling path of the light beam travels in the direction of the second plane wires 125C and 125F leaving the incident light side surfaces 113C and 113F from the first plane wires 124C and 124F adjacent to the incident light side surfaces 113C and 113F. In the progressing process, the probability of colliding with the second plane wires 125C and 125F is greater than the probability of colliding with the first plane wires 124C and 124F. Therefore, in order to increase the chance that the light rays are reflected and turn in the direction toward the light exit surfaces 111C and 111F, in these embodiments shown in FIGS. 11 and 13, the second plane wires 125C and 125F are the first plane. It is designed to have a larger area and a larger angle than the wires 124C and 124F. Therefore, the light guide plates 10C and 10F converge the light beam by a plurality of special asymmetric light guide microstructures 12C and 12F, and reduce the stray light, thereby further reducing the full width at half maximum (FWHM). The effective light emitted through the light exit surfaces 111C and 111F is increased, and the brightness of the emitted light is improved.

  As shown in FIG. 14, the display device of the present invention includes a backlight module 1 and a display panel 2. Since the structure of the backlight module 1 is as described above, the description thereof is omitted here. The display panel 2 is provided outside the optical film 20 of the backlight module 1, and provides a necessary backlight for the display panel 2 through the backlight module 1.

  As mentioned above, although the Example of this invention was disclosed, this invention is not limited by the Example mentioned above. A person skilled in the art can implement equivalent embodiments of various changes, equivalent changes such as decoration, and the like using the technical contents disclosed above without departing from the scope of the technical contents of the present invention. Unless it deviates from the contents of the technical means of the present invention, any simple corrections, equivalent changes and decorations made to the above-described embodiment according to the technical contents of the present invention are all within the scope of the technical contents of the present invention. Belongs.

1: Backlight module 2: Display panels 10A, 10B, 10C, 10D, 10E, 10F: Light guide plates 11A, 11B, 11C, 11D, 11E, 11F: Light guide plate bodies 111A, 111B, 111C, 111D, 111E, 111F: Light exit surfaces 112A, 112B, 112C, 112D, 112E, 112F: Reflective surfaces 113A, 113B, 113C, 113D, 113E, 113F: Incident light side surfaces 12A, 11B, 11C, 11D, 11E, 11F: Light guiding microstructures 120A, 120B, 120C, 120D, 120E, 120F: Center lines 121A, 121B, 121C, 121D, 121E, 121F: Circular planes 122A, 122B, 122C, 122D, 122E, 122F: Inclined circumferential surface 123C: Bottom planes 124C, 124F : 1st pre 125C, 125F: second plane wire 126E: opening H: steps L1, L2 with respect to the reflecting surface of the circular plane, L2: normal θ1, θ2: depression angle α1: between the center line and the normal passing through the center of the circular plane Outer angle α2 with respect to the reflecting surface of the first plane wire: Outer angle with respect to the reflecting surface of the second plane wire β1: Inner angle with respect to the reflecting surface of the first plane wire β2: Inner angle with respect to the reflecting surface of the second plane wire 20: Optical film 30: Light source 40 : Light guide plate 41: Reflecting surface 42: Light guide fine structure 43: Light incident surface 44: Light exit surface

Claims (10)

A light guide plate body including a light exit surface, a reflective surface, and an incident light side surface;
A plurality of light guide microstructures formed on the reflective surface of the light guide plate body;
Including
The light exit surface and the reflection surface are respectively located on opposite sides of the light guide plate body, and the incident light side surface is located on a side of the light guide plate body,
The light guide microstructure includes a circular plane and an inclined circumferential surface, the circular plane is parallel to the reflecting surface, forms a step with respect to the reflecting surface, and the inclined circumferential surface is A light guide plate extending from the circumference of the circular plane to the reflecting surface.   The light guide microstructure protrudes from the reflection surface, the light guide microstructure includes a center line orthogonal to the reflection surface, and a circular plane of the light guide microstructure is located outside the reflection surface. Item 4. The light guide plate according to Item 1.   The light guide microstructure protrudes from the reflection surface and defines a bottom plane in the reflection surface, the circular plane of the light guide microstructure is located outside the reflection surface, and the light guide microstructure Includes a center line, the center line is inclined from the center of the circular plane toward the incident light side surface and extends to the center of the bottom plane, and passes through the center line and the center of the circular plane. The light guide plate according to claim 1, which forms a depression angle that is an acute angle with the normal line.   The light guide microstructure protrudes from the reflective surface, the circular plane of the light guide microstructure is located outside the reflective surface, the light guide microstructure includes a center line, The inclined circumferential surface includes a first plane wire facing the incident light side surface and a second plane wire facing away from the incident light side surface, and the first plane wire and the second plane wire are respectively incident light directions of the center line. The angle of the external angle formed with respect to the reflective surface of the first plane wire is different from the angle of the external angle formed with respect to the reflective surface of the second plane wire, The light guide plate according to claim 1, wherein the light guide fine structure is formed in an asymmetric structure.   The light guide microstructure is recessed inward from the reflective surface, the light guide microstructure includes a center line orthogonal to the reflective surface, and the circular plane of the light guide microstructure is located inside the reflective surface. The light guide plate according to claim 1.   The light guide microstructure is recessed inward from the reflective surface to define an opening in the reflective surface, and a circular plane of the light guide microstructure is located inside the reflective surface, the light guide microstructure The structure includes a center line, and the center line is inclined from the center of the circular plane toward the incident light side surface and extends to the center of the opening, and the center line and the center of the circular plane The light guide plate according to claim 1, wherein the light guide plate forms a depression angle that is an acute angle with a normal line passing through.   The light guide microstructure is recessed inward from the reflective surface, the circular plane of the light guide microstructure is located inside the reflective surface, the light guide microstructure includes a center line, and the light guide microstructure The inclined circumferential surface of the structure includes a first plane wire facing the incident light side surface and a second plane wire facing away from the incident light side surface, and each of the first plane wire and the second plane wire is incident on the center line. The inner angle formed with respect to the reflecting surface of the first plane wire is located on both sides facing each other along the optical direction, and the inner angle formed with respect to the reflecting surface of the second plane wire is The light guide plate according to claim 1, wherein the light guide microstructure is formed in an asymmetric structure.   The light guide plate according to claim 1, wherein a plurality of light emission fine structures are formed on a light emission surface of the light guide plate. A light guide plate according to any one of claims 1 to 8,
At least one optical film installed outside the light exit surface of the light guide plate;
A light source that is provided outside the incident light side surface of the light guide plate, and whose light emission direction faces the incident light side surface;
Including backlight module. The backlight module according to claim 9;
A display panel provided outside the optical film of the backlight module.

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