WO2021237849A1

WO2021237849A1 - Light guide plate and planar light source having light guide plate

Info

Publication number: WO2021237849A1
Application number: PCT/CN2020/098041
Authority: WO
Inventors: 盛玉林
Original assignee: 昆山市诚泰电气股份有限公司
Priority date: 2020-05-29
Filing date: 2020-06-24
Publication date: 2021-12-02
Also published as: CN111580211A

Abstract

A light guide plate (10) and a planar light source having the light guide plate (10), relating to the technical field of backlight sources. A reflecting surface (101) of the light guide plate (10) is provided with a plurality of light guide network points (104) which are arranged at intervals and have a diameter smaller than 0.1 mm. The minimum distance between every two adjacent light guide network points (104) is at least equal to the diameter of the light guide network points (104). The diameter of the light guide network points (104) is reduced, and the light guide network points (104) are densely distributed, thereby achieving the effect that the light guide network points (104) cannot be distinguished by naked eyes from a light exit surface (102) of the light guide plate (10). In addition, the light exit surface (102) of the light guide plate (10) is configured to be a smooth plane, or a rough surface provided with an uneven microstructure, to adjust the emergent light form. The planar light source using the light guide plate (10), such as a backlight module and a planar lamp, does not use a diffusion plate (70), thereby lightening and thinning the planar light source, and reducing cost.

Description

Light guide plate and plane light source with the light guide plate

Technical field

The invention relates to a light guide plate and a plane light source with the light guide plate, and belongs to the technical field of backlight sources.

Background technique

The light guide plate generally has a light-incident surface, a light-emitting surface connected to the light-incident surface, and a reflective surface disposed opposite to the light-emitting surface. In a common side light source module, its main function is to configure the The light emitted by the light-emitting element on the side light-incident surface is guided to the light-emitting surface of the light guide plate through the reflective surface to form a surface light source. In order to form a uniform surface light source when light is emitted from the light-emitting surface, a number of micro-protrusions or depressions distributed in a net shape are usually distributed on the reflecting surface to form light guide dots. These light guide dots can be ink dots or hot pressing Dots, injection molding dots, etc., the principle of the light guide plate is: the light from the light source enters the light guide plate from the light incident surface and irradiates the light guide dots on the reflective surface. The light guide dots are used to destroy the total reflection of the light source and make the light The light guide mesh points are diffused to various angles, so that the light will form a uniform surface light source when it comes out of the light guide plate, and realize the purpose of transforming the light source from a linear light source to a surface light source. The light guide plate is generally used with a reflective layer on one side of its reflective surface, and a diffuser on the side of its light-emitting surface. The purpose of the reflective layer is to reflect the light exposed from the reflective surface of the light guide plate back into the light guide plate to improve the use of light. Efficiency; the purpose of the diffuser is to further diffuse the light to make the light softer.

At present, the light guide dots set on the light guide plate used in the prior art are all large in size. The light enters the light guide plate from the light entrance surface and then exits the light exit surface. No matter how the light exit surface is set, the light guide can be distinguished by the naked eye. Outlets. Therefore, when the above-mentioned light guide plate is applied to a flat light source such as a flat lamp or a backlight module, the diffuser plate provided on the light-emitting surface is an indispensable component. The diffuser plate can further diffuse the light through its own structure. Achieve the effect that the light guide dots are invisible to the naked eye. However, as the demand for flat light sources becomes thinner and thinner and costs are controlled, the above-mentioned flat light source structures that require the use of light guide plates and diffuser plates at the same time no longer meet the development of market demand.

Summary of the invention

In order to solve the above technical problems, the present invention provides a light guide plate and a planar light source with the light guide plate. The light guide plate can reach the naked eye can not distinguish the light guide dots without using a diffuser, thereby eliminating the need for the planar light source. The set diffuser plate realizes the thinner and thinner flat light source and saves the cost.

The technical scheme of the present invention is:

The invention discloses a light guide plate. The light guide plate has a front surface and a back surface that are arranged oppositely. The front surface is a reflective surface and the back surface is a light-emitting surface. , The reflecting surface is provided with a plurality of light guide mesh points arranged at intervals, the diameter of the light guide mesh points are all less than 0.1 mm, and the minimum distance between two adjacent light guide mesh points is at least equal to the light guide mesh point The diameter of the dots; the light-emitting surface is a smooth plane or a rough surface with uneven microstructures.

Its further technical solutions are:

The diameter of the light guide dots is one of the following two ways:

1. The diameters of the light guide dots are the same and all are less than 0.1mm;

2. The diameters of the light guide dots are inconsistent and all are less than 0.1mm;

And the minimum distance between two adjacent light guide dots is one of the following two ways:

1. The minimum distance between two adjacent light guide dots is consistent and at least equal to the diameter of the light guide dots;

2. The minimum distance between two adjacent light guide dots is inconsistent and is at least equal to the diameter of the light guide dots.

Its further technical solutions are:

The arrangement of the light guide dots is one of the following two ways:

1. The light guide dots are arranged at intervals on the reflecting surface in a matrix;

2. The light guide mesh points are randomly arranged on the reflecting surface in a disorderly manner.

Its further technical solutions are:

The light guide dots are formed on the reflective surface through one of a hot pressing process, a laser engraving process, a pad printing process, and a small dot printing process.

Its further technical solutions are:

When the light-emitting surface is a rough surface with uneven microstructures, the uneven microstructures are one of a prism structure, a line structure, a grid structure, an orange peel structure, a matte surface structure, and a matte surface structure.

Its further technical solutions are:

The prism structure is one of the following structures:

1. The cross section of the prism structure in the direction perpendicular to the light exit surface is triangular, and the shape of the prism structure in the direction parallel to the light exit surface is polygon;

2. The cross section of the prism structure in the direction perpendicular to the light exit surface is a semicircle convex or recessed on the light exit surface, and the prism structure is in a direction parallel to the light exit surface The shape is round.

Its further technical solutions are:

A hardened layer is formed on the surface of the light emitting surface.

The present invention also discloses a planar light source with the above-mentioned light guide plate. The planar light source includes the light guide plate, and further includes a back plate, a reflective layer, a light source, and an outer frame. The reflective layer is arranged to reflect the light guide plate. On the side of the surface, the back plate is arranged on the side of the reflective layer facing away from the light guide plate, the back plate, the reflective layer and the light guide plate are fixed on the inner side of the outer frame at the edges, and the light source is fixed in the outer frame and located in At the light incident surface of the light guide plate, the reflective layer is one of the following two structures:

1. The reflective layer is a reflective sheet with a sheet-like structure;

2. The reflective layer is the reflective surface of the back plate formed on the side surface of the back plate facing the light guide plate.

Its further technical solutions are:

The planar light source further includes a buffer sheet, and the buffer sheet is arranged between the reflection sheet and the back plate.

Its further technical solutions are:

The light source is one of LED, OLED and laser, and the plane light source is a plane lamp or a backlight module.

The beneficial technical effects of the present invention are:

1. In this application, hot pressing, laser engraving, pad printing and small dot screen printing technology are used to reduce the diameter of the light guide dots on the reflective surface of the light guide plate to less than 0.1mm, and the light guide dots are arranged densely, so that The light output of the light-emitting surface of the light guide plate can be more uniform, so that the naked eye cannot distinguish the light-guiding dots without using the diffuser, so as to avoid the appearance of uneven light on the light-emitting surface caused by the excessively large light-guiding dots. To the shadow of the light guide dots;

2. In this application, the light-emitting surface of the light guide plate is set as a smooth plane or a rough surface with uneven microstructures. When the light reflected by the light-guiding dots is emitted from the light-emitting surfaces with different surface structures, different light patterns can be produced. At the same time, it has a certain light diffusion effect;

3. In this application, by changing the setting mode of the light guide dots on the light guide plate, the original diffuser can achieve the function of the original diffuser, so that the naked eye cannot distinguish the dots. Therefore, it can be directly used in flat light sources such as flat lights and backlight modules. Eliminate the commonly used diffuser, so as to achieve the light and thin flat light source, while saving costs.

Description of the drawings

Fig. 1 is a schematic diagram of the composition structure of one of the existing planar light sources;

Fig. 2 is a schematic diagram of the composition structure of the second existing planar light source;

3 is a schematic diagram of the structure of the light guide plate of the present invention;

4 is a schematic diagram of the structure of the planar light source of the present invention;

Fig. 5 is a second schematic diagram of the structure of the planar light source according to the present invention;

Fig. 6 is a third schematic diagram of the structure of the planar light source according to the present invention;

in:

10-light guide plate; 101-reflective surface; 102-light-emitting surface; 103-light-incident surface; 104-light-guiding dots;

20-backplane;

30-reflective layer; 301-reflective sheet; 302-reflection surface of back plate;

40-light source;

50-buffer film;

60-Outer frame;

70-Diffusion plate.

Detailed ways

In order to be able to understand the technical means of the present invention more clearly and implement it in accordance with the content of the specification, the specific implementation of the present invention will be described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention, but not To limit the scope of the present invention.

The following specific embodiments describe in detail the specific structure of the light guide plate described in the present application.

The light guide plate 10 described in the present application has a front side and a back side that are opposed to each other. The front side is a reflective surface 101 and the back side is a light-emitting surface 102. The sidewalls of the light guide plate adjacent to the reflective surface and the light-emitting surface form the light-incident surface 103. The light incident surface is generally two opposite sides of the light guide plate. The material of the light guide plate in this application can be selected from PMMA, PC, PS and other transparent plastics. The molding method can be extrusion molding. The molded light guide plate is an extruded light guide plate, or it can be injection molded. In the molding method, the formed light guide plate is an injection-type light guide plate; in addition, the light guide plate can also be made of transparent glass. The material and molding method of the light guide plate can be adjusted according to requirements.

The technical improvements of the light guide plate 10 in this application are as follows:

1. The reflective surface 101 of the light guide plate 10 is provided with a number of light guide dots 104 arranged at intervals, the diameter of the light guide dots are all less than 0.1 mm, and the minimum distance between two adjacent light guide dots is at least It is equal to the diameter of the light guide dot.

The shape of the light guide dots in this specific embodiment can be one of a circle, an ellipse, a triangle, a polygon, etc. The diameter of the light guide dot is the average diameter of the cross section of the light guide dot parallel to the reflective surface of the light guide plate . The diameters of the light guide dots 104 may be the same or different, but the diameters of the light guide dots need to be less than 0.1 mm.

The minimum distance between two adjacent light guide dots 104 may be the same or different, but the minimum distance between two adjacent light guide dots must be at least equal to the diameter of the light guide dots, that is, the minimum distance needs to ensure the same The distance between two adjacent light guide dots will not be too small to cause overlap or excessive density. The optimal minimum distance between two adjacent light guide dots is equal to 2-3 times the diameter of the light guide dot It is the diameter of light guide dots.

The above-mentioned light guide dots may be arranged in a matrix on the reflective surface 101 of the light guide plate at intervals, or randomly arranged on the reflective surface 101 of the light guide plate at intervals.

The light guide dots 104 in this application are formed on the reflective surface of the light guide plate 10 through one of a hot pressing process, a laser engraving process, a pad printing process, and a small dot printing process, wherein the hot pressing process, the laser engraving process, The pad printing process and the small dot printing process are both conventional technical solutions in the field, and will not be repeated in this application.

In this application, hot pressing, laser engraving, pad printing and small dot screen printing technology are used to reduce the diameter of the light guide dots on the reflective surface of the light guide plate to less than 0.1mm, and the light guide dots are arranged densely, so that the light guide plate emits light The light output of the surface can be more uniform, so that the naked eye cannot distinguish the light guide dots without using the diffuser, avoiding the naked eye to see the uneven light on the light emitting surface caused by the light guide dots being too large to see the light guide. In the case of the shadow of the dots, the setting of the diffuser can be cancelled after the light guide plate reaches this performance, thereby saving costs.

2. The light exit surface 102 of the light guide plate 10 is a smooth flat surface or a rough surface with uneven microstructures. The light reflected by the light guide mesh points is emitted from the light-emitting surface, so the surface structure of the light-emitting surface is different, and the light type of the light is different. When the light-emitting surface is smooth, the light pattern of the light does not produce different patterns of light and dark; when the light-emitting surface has a rough surface with uneven microstructures, the light pattern of the light is completely different according to the rough surface structure. . Figure 3 of the specification shows that the light-emitting surface is a smooth plane and several different rough surface structures.

When the light-emitting surface 102 is a rough surface with uneven microstructures, the uneven microstructures are one of a prism structure, a line structure, a grid structure, an orange peel structure, a matte surface structure, and a matte surface structure.

The above-mentioned prism structure is one of the following structures: 1) The cross section of the prism structure in the direction perpendicular to the light exit surface is a triangle, and the shape of the prism structure in the direction parallel to the light exit surface is a polygon, and the polygon It can be one of a regular quadrilateral, a regular pentagon, a regular hexagon, and a rhombus. 2) The cross section of the prism structure in the direction perpendicular to the light exit surface is a semicircle convex or recessed on the light exit surface, and the shape of the prism structure in the direction parallel to the light exit surface is a circle. In addition, other forms of prism structures can also be used.

The above-mentioned line structure is a plurality of straight lines arranged in parallel on the surface of the light-emitting surface, and the plurality of straight lines are parallel straight lines that are convex on the light-emitting surface or recessed on the light-emitting surface. The above-mentioned grid structure is a grid-like pattern formed on the surface of the light-emitting surface, the above-mentioned orange peel structure is a pattern that resembles an orange peel pattern formed on the surface of the light-emitting surface, and the above-mentioned frosted surface structure is formed after polishing The above-mentioned matte surface structure is a matte surface formed after chemical water erosion treatment. Prism structure, line structure and grid structure can make the light emitting type have different light diffusion function, but it is more reflected in the light emitting type with different light and dark patterns; orange peel structure, frosted surface structure and matte surface structure make The light-emitting surface has a certain degree of obscuration. On the basis of slightly changing the light-emitting type, it is more embodied in a certain light diffusion function, which can make the light-emitting light more uniform and soft.

In addition, a hardened layer is formed on the surface of the light-emitting surface 102, and the hardened layer is a hardened layer formed on the surface of the light-emitting surface in order to prevent scratches, abrasions, and bruises on the light-emitting surface of the light guide plate 10. The layer can be hardened through different processes according to the material of the light guide plate, such as spraying hard coating, depositing metal hardening layer, etc. The hardening layer is formed by conventional technical solutions well known to those skilled in the art , So I won’t repeat it in this application.

This specific embodiment also records a backlight module in detail, and the backlight module has the following structures:

1. In addition to the light guide plate 10 with the above structure, the backlight module is also provided with a back plate 20, a reflective layer 30 and a light source 40, wherein the reflective layer 30 is a reflective sheet 301 with a sheet-like structure. The reflective layer 30 (reflective sheet 301) is arranged on the side facing the reflective surface 101 of the light guide plate 10, the back plate 20 is arranged on the side of the reflective layer 30 (reflective sheet 301) facing away from the light guide plate 10, and the light source 40 is arranged on the side of the light guide plate 10 103 places on the light-incident surface. For the specific structure of the backlight module, refer to the corresponding structure described in FIG. 4.

2. In addition to the structure described in (1) above, the backlight module also includes a buffer sheet 50, which is an opaque sheet and is arranged between the reflective sheet 301 and the back plate 20. For the specific structure of the backlight module, refer to the corresponding structure described in FIG. 6.

3. In addition to the light guide plate 10 with the above structure, the backlight module is also provided with a back plate 20, a reflective layer 30 and a light source 40, wherein the reflective layer 30 is formed on the side surface of the back plate 20 facing the light guide plate背板reflective surface 302. The back plate 20 is disposed on the reflective surface 101 side of the light guide plate 10, the back plate reflective surface 302 is located between the back plate 20 and the reflective surface 101 of the light guide plate 10, and the light source 40 is disposed on the light incident surface 103 of the light guide plate 10. For the specific structure of the backlight module, refer to the corresponding structure described in FIG. 5.

The backplane in the above structure usually adopts a metal material backplane or a plastic material backplane, and the light source used is one of LED, OLED, and laser.

In the backlight modules of the above three structures, the diffuser plate arranged on the light-emitting surface side of the light guide plate in the traditional backlight module is eliminated. The diameter of the set light guide dots is reduced, and the diameter of the light guide dots is reduced to less than 0.1mm, and the light guide dots are arranged densely, so that the light from the light exit surface of the light guide plate can be more uniform, so that when not in use In the case of the diffuser, the naked eye cannot distinguish the light guide dots, so as to prevent the naked eye from seeing the uneven light on the light exit surface caused by the excessively large light guide dots, and thus see the shadow of the light guide dots; at the same time, the setting of the diffuser is cancelled. Later, the backlight module can be made thinner while saving costs. In addition, the different structures of the light-emitting surface of the light guide plate can diversify the light-emitting type of the backlight module.

This specific embodiment also describes in detail a flat lamp, which has the following structures:

1. In addition to the structure of the backlight module (1), it also includes an outer frame 60 and a power supply. The backlight module (1) is fixed in the outer frame 60, and the power supply is electrically connected to the light source in the backlight module (1). Sexual connection, see the complete structure described in Figure 4 for the specific structure.

2. In addition to the structure of the above-mentioned backlight module (2), it also includes an outer frame 60 and a power source. The above-mentioned backlight module (2) is fixed in the outer frame 60, and the power source is electrically connected to the light source in the backlight module (2). Sexual connection, see the complete structure described in Figure 6 for the specific structure.

3. In addition to the structure of the backlight module (3), it also includes an outer frame 60 and a power supply. The backlight module (3) is fixed in the outer frame 60, and the power supply is electrically connected to the light source in the backlight module (3). Sexual connection, see the complete structure described in Figure 5 for the specific structure.

The outer frame set in the above-mentioned flat lamp is a frame structure, the backlight module (mainly the back plate, the reflective layer, the light guide plate and the optional buffer sheet) is fixed on the inner side of the outer frame at the edge, and the light source is fixed to the outer frame The inside is located at the light incident surface of the light guide plate.

In the flat lamps with the above three structures, the diffuser plate arranged on the light-emitting surface side of the light guide plate in conventional lamps of this type is eliminated. The diameter of the set light guide dots is reduced, and the diameter of the light guide dots is reduced to less than 0.1mm, and the light guide dots are arranged densely, so that the light output from the light exit surface of the light guide plate can be more uniform, so that no diffusion is used. In the case of the plate, the naked eye cannot distinguish the light guide dots, so as to avoid the situation where the naked eye can see the uneven light on the light exit surface caused by the excessive light guide dots, so that the shadow of the light guide dots can be seen; at the same time, the setting of the diffuser is cancelled. , Can make the flat lamp thinner and save cost at the same time. In addition, the light-emitting surface of the light guide plate is provided with different structures, so that the light-emitting type of the flat lamp can be diversified.

The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. It should be pointed out that for those of ordinary skill in the art, several improvements can be made without departing from the technical principles of the present invention. And variants, these improvements and variants should also be regarded as the protection scope of the present invention.

Claims

A light guide plate, characterized in that: the light guide plate (10) has a front side and a back side opposed to each other, wherein the front side is a reflective surface (101), the back side is a light emitting surface (102), and the light guide plate is connected to the reflective surface and the light emitting surface. Adjacent side walls form a light incident surface (103), and a number of light guide mesh points (104) arranged at intervals are provided on the reflective surface (101), and the diameter of the light guide mesh points are all less than 0.1 mm, and The minimum distance between two adjacent light guide dots is at least equal to the diameter of the light guide dot; the light exit surface (102) is a smooth plane or a rough surface with uneven microstructures.
The light guide plate according to claim 1, wherein:

The diameter of the light guide dots (104) is one of the following two ways:

1. The diameters of the light guide dots (104) are consistent and less than 0.1mm;

2. The diameters of the light guide dots (104) are inconsistent and all are less than 0.1mm;

And the minimum distance between two adjacent light guide dots (104) is one of the following two ways:

1. The minimum distance between two adjacent light guide dots (104) is consistent and at least equal to the diameter of the light guide dots;

2. The minimum distance between two adjacent light guide dots (104) is inconsistent and is at least equal to the diameter of the light guide dots.
The light guide plate according to claim 1, wherein the arrangement of the light guide dots (104) is one of the following two methods:

1. The light guide dots (104) are arranged at intervals on the reflecting surface (101) in a matrix;

2. The light guide dots (104) are randomly arranged on the reflective surface (101) in a disorderly manner.
The light guide plate according to claim 1, wherein the light guide dots (104) are formed on the reflective surface by one of a hot pressing process, a laser engraving process, a pad printing process, and a small dot printing process (101) on.
The light guide plate according to claim 1, wherein when the light exit surface (102) is a rough surface with uneven microstructures, the uneven microstructures are prism structure, line structure, grid structure, One of orange peel structure, matte surface structure and matte surface structure.
5. The light guide plate of claim 5, wherein the prism structure is one of the following structures:

1. The cross section of the prism structure in the direction perpendicular to the light exit surface is triangular, and the shape of the prism structure in the direction parallel to the light exit surface is polygon;

2. The cross-section of the prism structure in the direction perpendicular to the light exit surface is a semicircle convex or recessed on the light exit surface, and the prism structure is in a direction parallel to the light exit surface The shape is round.
The light guide plate according to claim 1, wherein a hardened layer is formed on the surface of the light emitting surface (102).
A planar light source having the light guide plate according to any one of claims 1 to 7, characterized in that it comprises the light guide plate (10), and further comprises a back plate (20), a reflective layer (30), and a light source ( 40) and an outer frame (60), the reflective layer is arranged on the side facing the reflective surface of the light guide plate, the back plate is arranged on the side of the reflective layer facing away from the light guide plate, the back plate and the reflective layer The light guide plate is fixed on the inner side of the outer frame at the edge, the light source is fixed in the outer frame at the light incident surface of the light guide plate, and the reflective layer is one of the following two structures:

1. The reflective layer is a reflective sheet (301) with a sheet-like structure;

2. The reflective layer is formed on the back plate reflective surface (302) on the side surface of the back plate facing the light guide plate.
The planar light source according to claim 8, wherein the planar light source further comprises a buffer sheet (50), and the buffer sheet (50) is arranged between the reflective sheet (301) and the back plate (20).
The planar light source according to claim 8, wherein the light source is one of LED, OLED and laser, and the planar light source is a planar lamp or a backlight module.