CN105445844A - Light guide plate, manufacturing method of same, and backlight module - Google Patents

Abstract

The invention discloses a light guide plate, which comprises a light guide plate body, the light guide plate body has a bottom surface and a light exit surface opposite to each other, the light guide plate is provided with a diffusion layer on the light exit surface, the light guide plate is provided with a diffuse reflection layer on the bottom surface, and the light guide plate A reflection layer is provided on a side of the diffuse reflection layer away from the main body of the light guide plate. The invention also discloses a manufacturing method of the light guide plate and a backlight module. The diffusion layer of the light guide plate provided by the present invention can play the role of the diffusion sheet in the optical basic structure of the traditional backlight module, and the combination of the diffuse reflection layer and the reflective layer can play the role of reflection in the optical basic structure of the traditional backlight module. sheet, so the backlight module using the light guide plate provided by the present invention can omit the reflection sheet and the diffusion sheet, thereby simplifying the assembly process of the backlight module, and avoiding the light guide plate and the reflection sheet and/or diffusion during the assembly process. The poor appearance caused by the friction of the sheet can also be avoided, and the poor appearance caused by the wave shape generated by the reflective sheet after assembly can also be avoided.

Description

Light guide plate, manufacturing method of light guide plate, and backlight module

technical field

The invention relates to the field of display technology, in particular to a light guide plate, a manufacturing method of the light guide plate and a backlight module.

Background technique

At present, the backlight module commonly used in liquid crystal displays has an optical basic structure of reflective sheet, light guide plate, diffuser sheet, brightness enhancement sheet and reflective brightness enhancement film. However, the backlight module using the above optical basic structure will have at least the following defects in the production process: first, the optical basic structure has five layers, and the assembly complexity is high, and the gaps between multiple layers make the backlight module The overall light efficiency of the group is low; secondly, the light guide plate is easy to rub against the reflective sheet and the diffuser sheet during the assembly process, resulting in poor appearance; moreover, the reflective sheet has poor stiffness, and it is easy to produce a wavy appearance after assembly bad. Therefore, it is necessary to simplify the optical basic structure of the current backlight module.

Contents of the invention

The main purpose of the present invention is to solve the technical problem of high complexity in the assembly of traditional backlight modules.

To achieve the above object, the present invention provides a light guide plate, the light guide plate includes a light guide plate body, the light guide plate body has an opposite bottom surface and a light exit surface, and the light guide plate is provided with a diffusion layer on the light exit surface, The diffusion layer is used to uniformly transmit light from the light-emitting surface of the light guide plate body, and the light guide plate is provided with a diffuse reflection layer on the bottom surface, and the diffuse reflection layer is used to allow light The bottom surface of the light guide plate is diffusely reflected to the light-emitting surface, and the light guide plate is provided with a reflective layer on the side of the diffuse reflective layer away from the light guide plate body, and the reflective layer is used to prevent light from being transmitted from the diffuse reflective layer out.

Preferably, the light guide plate is provided with protrusions on the light-emitting surface, and the protrusions cover the light-emitting surface to form the diffusion layer.

Preferably, the protrusions are granular, the protrusions include first protrusions and second protrusions, the size of the first protrusions is different from that of the second protrusions, and/or, the The height of the first protrusion is different from that of the second protrusion.

Preferably, the diffuse reflection layer of the light guide plate is a dot layer.

Preferably, the light guide plate body also has a light-incident side adjacent to the bottom surface and the light-emitting surface, and the density of the dots of the diffuse reflection layer is from the end close to the light-incident side to the light-incident side one end gradually increases.

Preferably, the reflective layer is a film layer laminated on the diffuse reflective layer by thermocompression.

In addition, in order to achieve the above object, the present invention also provides a method for making a light guide plate, which includes the steps of: drying and melting the first raw material, and then forming a light guide plate body with opposite bottom surfaces and light-emitting surfaces by hot pressing; The light-emitting surface of the light guide plate body is hot-pressed to form a diffusion layer; the bottom surface of the light guide plate body is hot-pressed to form a diffuse reflection layer; and a reflective layer is formed on the side of the diffuse reflection layer away from the light guide plate body.

Preferably, the specific step of hot pressing the light-emitting surface of the light guide plate body to form a diffusion layer includes: performing a first hot-press on the light-emitting surface of the light guide plate body to form granular protrusions of a first height; The light-emitting surface of the light guide plate body is subjected to a second heat press to form granular protrusions of a second height; wherein, the first height is smaller than the second height, and the granular protrusions of the first height are different from the second height. The positions of the granular protrusions of the two heights are staggered.

Preferably, the diffuse reflection layer is a dot layer, and the light guide plate body also has a light-incident side adjacent to the bottom surface and the light-emitting surface, and the density of the dots is away from an end close to the light-incident side. One end on the light-incident side gradually increases.

Preferably, the specific steps of forming the reflective layer on the side of the diffuse reflective layer away from the light guide plate body include: drying and melting the second raw material, and stretching the second raw material into a reflective film; The reflective layer is formed by hot-press bonding on the diffuse reflective layer.

In addition, to achieve the above object, the present invention also provides a backlight module, including the light guide plate.

The light guide plate provided by the present invention is provided with a diffusion layer on the light-emitting surface of the light guide plate body, a diffuse reflection layer is provided on the bottom surface, and a reflection layer is also provided on the side of the diffuse reflection layer away from the light guide plate body, wherein the diffusion The layer can diffuse the light emitted from the light-emitting surface, that is, the diffusion layer can play the role of the diffusion sheet in the optical basic structure of the traditional backlight module. The diffuse reflection layer can make the light diffusely reflect from the bottom surface to the light-emitting surface uniformly. It can prevent light from being transmitted from the diffuse reflection layer, that is, the combination of the diffuse reflection layer and the reflection layer can play the role of the reflector in the optical basic structure of the traditional backlight module, that is, the light guide plate provided by the present invention integrates the traditional backlight The functions of the reflector, the light guide plate and the diffuser in the module, so the backlight module using the light guide provided by the present invention can save the reflector and the diffuser, thereby simplifying the assembly process of the backlight module and avoiding the assembly process. The friction between the light guide plate and the reflective sheet and/or the diffusion sheet causes poor appearance and reduced light efficiency, and also avoids the poor appearance and reduced light effect caused by the wave shape of the reflective sheet after assembly.

Description of drawings

1 is a schematic structural view of an embodiment of a light guide plate of the present invention;

Fig. 2 is the enlarged schematic diagram of II place in Fig. 1;

FIG. 3 is a schematic flowchart of an embodiment of a manufacturing method of a light guide plate of the present invention.

The realization of the purpose of the present invention, functional characteristics and advantages will be further described in conjunction with the embodiments and with reference to the accompanying drawings.

detailed description

It should be understood that the specific embodiments described here are only used to explain the present invention, not to limit the present invention.

The invention provides a light guide plate.

1 and 2, in one embodiment, the light guide plate includes a light guide plate body 10, the light guide plate body 10 has an opposite bottom surface 12 and a light exit surface 11, and the light guide plate is provided with a diffusion layer 20 on the light exit surface 11, The diffusion layer 20 is used to uniformly transmit light from the light-emitting surface 11 of the light guide plate body 10, and the light guide plate is provided with a diffuse reflection layer 30 on the bottom surface 12, and the diffuse reflection layer 30 is used to allow light to pass through the light from the light guide plate body 10. The bottom surface 12 is diffusely reflected to the light-emitting surface 11 , and the light guide plate is provided with a reflective layer 40 on the side of the diffuse reflective layer 30 away from the light guide plate body 10 , and the reflective layer 40 is used to prevent light from being transmitted from the diffusely reflective layer 30 . In this embodiment, the light guide plate can be made of PMMA (PolymethylMethacrylate, polymethyl methacrylate) or MS (MethylMethacrylate-styrenecopolymer, methyl methacrylate-styrene copolymer); the raw material of the reflective layer 40 can be PET (PolyethyleneTerephthalate, polyethylene terephthalate).

In the light guide plate provided in this embodiment, a diffusion layer 20 is provided on the light-emitting surface 11 of the light guide plate body 10, a diffuse reflection layer 30 is provided on the bottom surface 12, and a diffuse reflection layer 30 is provided on the side away from the light guide plate body 10. A reflective layer 40 is provided, wherein the diffuser layer 20 can diffuse the light emitted from the light-emitting surface 11, that is, the diffuser layer 20 can play the role of a diffuser in the optical basic structure of a traditional backlight module, and the diffuse reflective layer 30 can make The light is uniformly and diffusely reflected from the bottom surface 12 to the light-emitting surface 11, and the reflective layer 40 can prevent light from being transmitted from the diffuse reflective layer 30, that is, the combination of the diffuse reflective layer 30 and the reflective layer 40 can serve as the optical basic structure of a traditional backlight module. The role of the reflector in this embodiment, that is, the light guide plate provided by this embodiment integrates the functions of the reflector, light guide plate and diffuser in the traditional backlight module, so the backlight module using the light guide plate provided by this embodiment can save Remove the reflector and diffuser, which simplifies the assembly process of the backlight module, avoids the poor appearance and the reduction of light effect caused by the friction between the light guide plate and the reflector and/or diffuser during the assembly process, and also avoids the reflection of the reflector. The appearance of the wavy form after assembly is poor and the light effect is reduced.

In this embodiment, the light guide plate is provided with protrusions 23 on the light-emitting surface 11 , and the protrusions 23 cover the light-emitting surface 11 to form a diffusion layer 20 . Specifically, the protrusion 23 is granular, and the protrusion 23 includes a first protrusion 21 and a second protrusion 22, wherein the size of the first protrusion 21 is different from that of the second protrusion 22, and/or , the height of the first protrusion 21 is different from the height of the second protrusion 22 . In this embodiment, the height of the first protrusion 21 is lower than the height of the second protrusion 22; during the process of assembling the backlight module, the light guide plate may rub against the brightness enhancement sheet or other objects in contact with the light guide plate, causing the light to diffuse. The protrusions 23 of the layer 20 have two different heights, which can enhance the wear resistance of the diffusion layer 20 of the light guide plate, thereby ensuring the uniformity of the light energy of the light output surface 11 .

It should be emphasized that in this embodiment, the protrusions 23 include first protrusions 21 and second protrusions 22 with different sizes and/or heights, but this is not intended to limit the range of types of protrusions 23; In an embodiment, the types of protrusions 23 may be one type or more than three types.

In this embodiment, the diffuse reflection layer 30 of the light guide plate is a dot layer, and the dots 31 are concave points; further, the light guide plate body 10 also has a light incident side 13 adjacent to the bottom surface 12 and the light exit surface 11, and the diffuse reflection layer 30 The density of the grid dots 31 gradually increases from the end close to the light-incident side 13 to the end away from the light-incident side 13 . Here, the density of the dots 31 refers to the ratio of the area of the dots 31 to the area of the bottom surface 12 . In this embodiment, when the light guide plate is used in the backlight module, the light emitted by the light source of the backlight module enters the light guide plate from the light incident side 13, because the light at the end near the light incident side 13 and the light at the end far from the light incident side 13 Compared with the light, the light intensity gradually weakens, so in order to ensure the uniformity of the overall light on the light-emitting surface 11 of the light guide plate, the density of the dots 31 gradually increases from the end close to the light-incident side 13 to the end away from the light-incident side 13, so that The light at the end away from the light-incident side 13 can be better diffusely reflected.

In this embodiment, the reflective layer 40 of the light guide plate is a film layer bonded to the diffuse reflective layer 30 by thermocompression. On the one hand, the reflective layer 40 and the light guide plate body 10 can be firmly fixed on the diffuse reflective layer 30 by thermocompression. At the same time, on the other hand, it can avoid gaps between the reflective film and the bottom surface 12 of the light guide plate body 10 that affect the light reflection effect.

The invention also provides a backlight module.

In an embodiment, the backlight module includes the light guide plate in the foregoing embodiments.

The invention also provides a manufacturing method of the light guide plate.

Referring to Fig. 3, in one embodiment, the manufacturing method of the light guide plate includes the steps of:

In step S10 , the first raw material is dried and melted, and then heat-pressed to form a light guide plate body having opposite bottom surfaces and light-emitting surfaces.

In this embodiment, the first raw material may be PMMA (PolymethylMethacrylate, polymethylmethacrylate) or MS (MethylMethacrylate-styrenecopolymer, methylmethacrylate-styrene copolymer).

Step S20, forming a diffusion layer by hot pressing on the light-emitting surface of the light guide plate body;

In this embodiment, step S20 specifically includes:

Step S201, performing the first hot pressing on the light emitting surface of the light guide plate body to form granular protrusions of the first height;

Step S202, performing a second heat press on the light emitting surface of the light guide plate body to form granular protrusions of a second height;

Wherein, the first height is smaller than the second height, and the positions of the granular protrusions of the first height and the granular protrusions of the second height are staggered.

In this embodiment, the light-emitting surface of the light guide plate body is hot-pressed by a roller heat-pressing process, so that the light-emitting surface of the light guide plate body is covered with protrusions to form a diffusion layer, and the diffusion layer can diffuse the light emitted from the light-emitting surface. to make the light emitted from the light-emitting surface more soft and uniform; specifically, the protrusions of the diffusion layer are granular, and the granular protrusions on the light-emitting surface of the light guide plate body have two different sizes and heights. In terms of design, since a roller usually only has particles of one size and height, it is necessary to use rollers with particles of different sizes and heights to carry out two roller heat-pressing treatments on the light-emitting surface of the light guide plate body; among them, the first heat-pressing The lower height of the protrusions was obtained after the second heat pressing treatment, and the higher height protrusions were obtained after the second hot pressing treatment. If the order of the two hot pressing treatments was changed, the lower height protrusions could not be formed; The protrusions have two different heights, which can enhance the wear resistance of the diffusion layer of the light guide plate, thereby ensuring the uniformity of light energy on the light emitting surface.

Step S30, forming a diffuse reflection layer on the bottom surface of the light guide plate body by hot pressing.

In this embodiment, the diffuse reflection layer is a dot layer, and the light guide plate body also has a light-incident side adjacent to the bottom surface and the light-emitting surface. increase. Specifically, hot pressing is performed on the bottom surface of the light guide plate body by using a screen dot roller, so that the bottom surface of the light guide plate body is covered with dots to form a diffuse reflection layer, which can uniformly diffuse light from the bottom surface to the light-emitting surface; In practice, since the intensity of the light near the light-incident side is gradually weakened compared with the light at the end away from the light-incident side, in order to ensure the uniformity of the overall light on the light-emitting surface of the light guide plate, the density of the dots starts from the end near the light-incident side. It gradually increases toward the end away from the light-incident side, so that the light at the end away from the light-incident side can be better diffusely reflected.

In this embodiment, step S30 can be performed simultaneously with step S201 or step S202, so as to reduce the man-hours for processing the light guide plate and shorten the length of the processing equipment for the light guide plate, thereby improving the efficiency of manufacturing the light guide plate.

Step S40, forming a reflection layer on the side of the diffuse reflection layer away from the main body of the light guide plate.

In this embodiment, the reflective layer has a relatively high reflectivity, which is used to prevent light from being transmitted from the diffuse reflective layer, that is, the presence of the reflective layer can further enhance the light reflection ability of the light guide plate at the bottom surface, thereby reducing the The loss of light energy improves the overall light efficiency of the backlight module using the light guide plate.

The light guide plate manufactured in this embodiment is provided with a diffusion layer on the light-emitting surface of the light guide plate body, a diffuse reflection layer on the bottom surface, and a reflective layer on the side of the diffuse reflection layer away from the light guide plate body, wherein, The diffusion layer can diffuse the light emitted from the light-emitting surface, that is, the diffusion layer can play the role of the diffusion sheet in the optical basic structure of the traditional backlight module, and the diffuse reflection layer can make the light diffusely reflect from the bottom surface to the light-emitting surface uniformly. The layer can prevent light from being transmitted from the diffuse reflection layer, that is, the combination of the diffuse reflection layer and the reflection layer can play the role of the reflector in the optical basic structure of the traditional backlight module, that is, the light guide plate manufactured in this embodiment integrates The functions of the reflector, the light guide plate and the diffuser in the traditional backlight module, so the backlight module using the light guide plate manufactured in this embodiment can save the reflector and the diffuser, thereby simplifying the assembly process of the backlight module and avoiding It avoids poor appearance and reduced light effect caused by friction between the light guide plate and the reflective sheet and/or diffuser during the assembly process, and also avoids poor appearance and reduced light effect due to the wave shape of the reflective sheet after assembly.

In this embodiment, the specific steps of step S40 include:

Step S401, drying and melting the second raw material, and then stretching it into a reflective film;

Step S402, bonding the reflective film on the diffuse reflective layer by thermocompression to form a reflective layer.

In this embodiment, the second raw material can be PET (Polyethylene Terephthalate, polyethylene terephthalate); The pressure-fitting method can make the reflective film firmly fixed on the bottom surface of the light guide plate body on the one hand, and on the other hand, avoid gaps between the reflective film and the bottom surface of the light guide plate body that affect the light reflection effect.

The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process conversion made by using the description of the present invention and the contents of the accompanying drawings, or directly or indirectly used in other related technical fields , are all included in the scope of patent protection of the present invention in the same way.

Claims (11)

1. A light guide plate, characterized in that the light guide plate comprises a light guide plate body, the light guide plate body has a relative bottom surface and a light exit surface, and the light guide plate is provided with a diffusion layer on the light exit surface, the diffusion The layer is used to uniformly transmit light from the light-emitting surface of the light guide plate body, and the light guide plate is provided with a diffuse reflection layer on the bottom surface, and the diffuse reflection layer is used to allow light Diffuse reflection to the light-emitting surface, the light guide plate is provided with a reflection layer on the side of the diffuse reflection layer away from the light guide plate body, and the reflection layer is used to prevent light from being transmitted from the diffuse reflection layer . 2 . The light guide plate according to claim 1 , wherein the light guide plate is provided with protrusions on the light-emitting surface, and the protrusions cover the light-emitting surface to form the diffusion layer. 3 . 3. The light guide plate according to claim 2, wherein the protrusions are granular, the protrusions include a first protrusion and a second protrusion, and the size of the first protrusion is the same as that of the The size of the second protrusions is different, and/or, the height of the first protrusion is different from that of the second protrusion. 4. The light guide plate according to claim 1, wherein the diffuse reflection layer of the light guide plate is a dot layer. 5. The light guide plate according to claim 4, wherein the light guide plate body also has a light-incident side adjacent to the bottom surface and the light-emitting surface, and the density of the dots of the diffuse reflection layer is closer to the light-emitting side. The one end on the light-incident side gradually increases toward the end away from the light-incident side. 6 . The light guide plate according to claim 1 , wherein the reflective layer is a thin film layer laminated on the diffuse reflective layer by thermocompression. 7 . 7. A method for making a light guide plate, characterized in that the method for making a light guide plate comprises the steps of: drying and melting the first raw material, and then heat-press forming a light guide plate body with opposite bottom surface and light-emitting surface; forming a diffusion layer by hot pressing on the light-emitting surface of the light guide plate body; hot pressing on the bottom surface of the light guide plate body to form a diffuse reflection layer; A reflection layer is formed on the side of the diffuse reflection layer away from the main body of the light guide plate. 8. The manufacturing method of the light guide plate according to claim 7, wherein the specific steps of forming the diffusion layer by hot pressing on the light-emitting surface of the light guide plate body include: Carrying out the first hot pressing on the light-emitting surface of the light guide plate body to form granular protrusions of the first height; performing a second heat press on the light-emitting surface of the light guide plate body to form granular protrusions of a second height; Wherein, the first height is smaller than the second height, and the positions of the granular protrusions of the first height and the granular protrusions of the second height are staggered. 9. The manufacturing method of the light guide plate as claimed in claim 7, wherein the diffuse reflection layer is a dot layer, and the light guide plate body also has a light incident side adjacent to the bottom surface and the light exit surface, The density of the dots gradually increases from an end close to the light-incident side to an end far away from the light-incident side. 10. The manufacturing method of the light guide plate according to claim 7, wherein the specific steps of forming the reflective layer on the side of the diffuse reflection layer away from the light guide plate body include: The second raw material is dried, melted, and then stretched into a reflective film; The reflective film is hot-press bonded on the diffuse reflective layer to form a reflective layer. 11. A backlight module, characterized in that the backlight module comprises the light guide plate according to any one of claims 1-6.