CN204496042U - A kind of composite light guide plate and liquid crystal display module thereof - Google Patents

Abstract

The utility model discloses a composite light guide plate and a liquid crystal display module thereof, comprising a light guide plate body having a light incident side, a light exit surface and a back surface, the light exit surface and the back surface of the light guide plate body are respectively equipped with The first slope and the second slope, the first slope and the second slope respectively form an angle β with the horizontal plane of the light guide plate, 0<β<20°, and the back of the light guide plate body has a composite reflection layer; Processing, the incident light at the same angle passes through the light guide plate for a longer total reflection optical path, and the light guide plate of the same size reduces the number of total reflections of light and reduces light loss.

Description

Composite light guide plate and liquid crystal display module thereof

technical field

The utility model relates to a composite light guide plate and a liquid crystal display module thereof.

Background technique

2 is a structural sectional view of an existing display module, which consists of a front frame of the module, a liquid crystal glass 1 , a plastic frame, an optical film 2 , a light guide plate 3 , a reflector 5 , a light source 4 and a rear case 6 . The reflector 5 and the light guide plate 3 are sequentially placed in the cavity of the back shell 6, and the back shell 6 is used as a structural support and part of the appearance function. This kind of structure is complex, the thickness of the whole machine is relatively thick, and the cost is high, and the back plate is generally made of metal or plastic. pieces, its color is single, it is difficult to make different appearance effects. The function of the reflective sheet 5 is that when the light is emitted from the back 33 of the light guide plate, the light can be reflected into the light guide plate 3 for recycling after being reflected by the reflective sheet 5 .

The existing light guide plate 3 generally uses PMMA material, and dots can be prepared by printing, injection, hot pressing, inkjet, etc. The structure of the light guide plate 3 is usually a cuboid, and the end surface of the corresponding light source is basically perpendicular to the light emitting surface after polishing, and the light guide plate 3 It is separated from the reflective sheet 5, and there is an air layer between the light guide plate 3 and the reflective sheet 5. Figure 1 shows the structure of the existing light guide plate. When the light source 4 is injected into the light guide plate 3, reflection and refraction will occur at the interface between PMMA and air, scattering will occur at the diffusion network or microstructure, and the critical angle of total reflection will occur. About 41°. When the incident angle I>41°, total reflection occurs at the interface between PMMA and air, and the light can always be reflected in the light guide plate and propagate forward. When the incident angle I′<41°, at the interface between PMMA and air, a part is emitted, and a part is refracted and emitted from the surface of the light guide plate 32 or 33 . Through the design of 33 dots on the back of the light guide plate, when the light is incident on the dots or microstructures, the light is scattered, thereby controlling part of the light to be emitted from the front 32 of the light guide plate, thereby realizing the backlight effect.

Contents of the invention

The purpose of the utility model is to provide a composite light guide plate, the light emitting surface and the back of the light guide plate body are respectively provided with a first slope and a second slope near the light incident side. The optical path of one total reflection of the light plate is also longer, and the number of total reflections of light is reduced for a light guide plate of the same size, and the light loss is also reduced.

Another object of the present utility model is to provide a liquid crystal display module. Compared with the existing display module, the use of the back shell can be eliminated due to the use of the composite light guide plate, and then it can be made into an ultra-thin display module, which can be used in Phones, tablets, monitors, and flat-screen TVs.

The technical solution of the utility model is: a composite light guide plate, including a light guide plate body having a light incident side, a light exit surface, and a back surface, and the light exit surface and the back surface of the light guide plate body respectively have first slopes near the light incident side and the second slope, the first slope and the second slope form an included angle β with the horizontal plane of the light guide plate, 0<β<20°, and the back of the light guide plate body has a composite reflection layer.

The composite reflective layer is integrated with the light guide plate body, and the reflective sheet can be bonded with optical glue, or the specular reflective layer can be made directly on the back by sputtering or chemical process. Because there is no air between the light guide plate body and the composite reflective layer, the difference in refractive index decreases and the total reflection angle becomes larger Right now If the existing right-angle structure of the light guide plate is used, the incident angle on the back of the light guide plate body will be smaller than the total reflection angle, that is At this time, total reflection will not occur, but partial reflection and most refraction will occur. The light refracted out of the light guide plate body will be absorbed and scattered through the composite reflection layer, and the light cannot continue to propagate forward. When the light enters the inclined surface or the interface, the incident angle of the light will be larger than that of the existing light guide plate body, that is, I'>I, correspondingly, the incident angle of the reflected light on the back of the light guide plate body will also be larger than that of the traditional light guide plate body. The light guide plate is large, that is, R'>R, within a certain angle, The light is totally reflected and can continue to travel forward. Moreover, after adding the slope treatment, the optical path of the total reflection of the incident light at the same angle through the light guide plate body is also longer, that is, L'>L, and the light guide plate of the same size reduces the number of total reflections of light and reduces the light loss. .

Further, the composite reflective layer at least includes a reflective layer and an appearance layer, which has various technical solutions:

One of the specific technical proposals of the composite reflective layer is: the composite reflective layer is sequentially composed of an optical adhesive layer, a reflective layer and an appearance layer from the back of the light guide plate body to the outside. Wherein, the optical coating 522 is a low-refractive-index coating; the optical bonding layer is a transparent viscous optical glue; and the reflective layer is a PET foam layer.

The second specific technical solution of the composite reflective layer is: the composite reflective layer consists of an optical adhesive layer, an optical coating layer, a reflective layer, and an appearance layer sequentially from the back of the light guide plate body to the outside. Wherein, the optical coating is a low-refractive-index coating; the optical bonding layer is a transparent viscous optical glue; and the reflection layer is a PET foam layer.

The third specific technical solution of the composite reflection layer is: the reflection layer is a high-reflection mirror film layer.

Further, the light guide plate body is made of transparent materials such as PMMA, Glass, and PC.

Another technical solution of the present utility model is: a liquid crystal display module comprising the above-mentioned composite light guide plate.

The utility model has the advantages of:

1. In the utility model, the light-emitting surface and the back of the light guide plate body have a first slope and a second slope near the light-incident side, respectively. Due to the slope treatment, the incident light at the same angle passes through the optical path of a total reflection of the light guide plate It is also larger, and the light guide plate of the same size reduces the number of total reflections of light and reduces light loss.

2. The utility model adds a composite reflection layer on the back of the light guide plate body. The composite reflection layer has a multi-layer structure, which is compatible with reflection and appearance functions. Compared with the existing display module, because of the use of the composite light guide plate, it can be canceled The use of the shell can further make an ultra-thin display module, which can be used in mobile phones, flat panels, monitors and flat panel TVs.

Description of drawings

Below in conjunction with accompanying drawing and embodiment the utility model is further described:

Figure 1 shows the structure of the existing light guide plate;

FIG. 2 is a structural cross-sectional view of an existing display module;

Fig. 3 is the composite light guide plate structure of the present invention;

Figure 4 is a comparison of the light guide path between the composite light guide plate of the present invention and the existing light guide plate;

Fig. 5 is the embodiment 1 of the composite light guide plate of the present invention;

Fig. 6 is embodiment 2 of the composite light guide plate of the present invention;

Fig. 7 is embodiment 3 of the composite light guide plate of the present invention;

Fig. 8 is the structure of the ultra-thin liquid crystal display module of the present invention.

Among them: 1 liquid crystal glass; 2 optical film assembly; 3 light guide plate; 3' light guide plate body; 31 (light guide plate/light guide plate body) light input side; 34 light guide plate dots or microstructure; 35 first slope; 36 second slope; 37 composite reflection layer; 371 reflection layer; 372 appearance layer; 373 optical bonding layer; 374 optical coating; 4 light source; 5 reflector; 6 back shell.

Detailed ways

Embodiment: As shown in FIG. 3 , a composite light guide plate includes a light guide plate body 3' having a light incident side 31, a light exit surface 32, and a back surface 33. The light exit surface 32 and the back surface 33 of the light guide plate body 3' are in The part close to the light-incident side 31 has a first slope 35 and a second slope 36 respectively. The first slope 35 and the second slope 36 respectively form an angle β with the horizontal plane of the light guide plate, 0<β<20°, and the light guide plate body The back of 3' has a composite reflective layer 37, and the composite reflective layer 37 has a multi-layer structure, which is compatible with reflection and appearance functions.

As shown in FIG. 4 , the composite reflective layer 37 is integrated with the light guide plate body 3 ′, and the reflective sheet can be pasted with optical glue, or the specular reflective layer can be made directly on the back by sputtering or chemical process. Because there is no air between the light guide plate body 3' and the composite reflective layer, the difference in refractive index decreases and the total reflection angle becomes larger Right now If the existing right-angle structure of the light guide plate is used, the incident angle at the back 33 of the light guide plate body will be smaller than the total reflection angle, that is At this time, total reflection will not occur, but partial reflection and most refraction will occur. The light refracted out of the light guide plate body 3 ′ will be absorbed and scattered by the underlying composite reflection layer, and the light cannot continue to propagate forward. In the present invention, when the light enters the inclined surface or the interface, the incident angle of the light will be larger than that of the existing light guide plate body, that is, I'>I. Correspondingly, the incident angle of the reflected light on the back of the light guide plate body It will also be larger than the traditional light guide plate, that is, R'>R, within a certain angle, The light is totally reflected and can continue to travel forward. Moreover, after adding the slope treatment, the optical path of the total reflection of the incident light at the same angle through the light guide plate body is also longer, that is, L'>L, and the light guide plate of the same size reduces the number of total reflections of light and reduces the light loss. .

The composite light guide plate can be realized in many ways, the main difference lies in the composite reflective layer.

Specific embodiment 1 of the composite reflective layer: as shown in FIG. 5 , the composite reflective layer 37 is composed of an optical adhesive layer 373 , a reflective layer 371 , and an appearance layer 372 . The optical bonding layer 373 is a transparent viscous optical adhesive, and its refractive index is lower than that of the material of the light guide plate, the lower the better. The reflective layer 371 is a PET foam layer, and its reflectivity can reach more than 97% by using its multi-layer air interface. The appearance layer 372 can be realized by coating or pasting other substrates or films with appearance functions. Through the optical bonding layer 373, the light guide plate body 3' and the reflective layer are combined together. According to design requirements, the thickness of the optical bonding layer 373 is generally greater than 10 um to ensure bonding strength.

Specific embodiment 2 of the composite reflective layer: as shown in FIG. 6 , the composite reflective layer 37 is composed of an optical adhesive layer 373 , an optical coating 374 , a reflective layer 371 , and an appearance layer 372 . Compared with Embodiment 1, the optical bonding layer 373 only plays a bonding role, and the optical coating 374 is a low-refractive-index coating, and light rays are totally reflected at this interface. Due to the high cost of the low-refractive-index optical glue, in this embodiment, the optical coating 374 can be made thin, and the optical bonding layer 373 can be made thick to ensure the bonding strength.

Specific embodiment 3 of the composite reflective layer: as shown in Figure 7, compared with embodiment 1 and embodiment 2, its composite reflective layer 37 comprises reflective layer 371 and appearance layer 372, and wherein reflective layer 371 is a high reflective mirror film layer . The high reflective mirror film layer can be realized by vacuum plating Al film, magnetron sputtering Al or Ag film, chemical coating and other processes. Through material and process optimization, the mirror reflectance of more than 98% can be achieved. When light is reflected on the back surface 33 of the light guide plate body in this embodiment, there will be a brightness loss of more than 2% every time it is reflected, and the more times of reflection, the more serious the light loss. The number of reflections should be reduced as much as possible, that is, it is necessary to accurately calculate and optimize the hypotenuse angle β of the light guide plate body 3 ′.

As shown in FIG. 8 , the ultra-thin display module adopting the above-mentioned composite light guide plate, compared with the existing display module, can eliminate the use of the back cover due to the use of the composite light guide plate. The display module can be used to make mobile phones, tablets, monitors and flat-screen TVs. Considering that the larger the size, the greater the weight of the product, and the higher the strength requirement, it is preferable to use Glass material as the light guide plate body.

The above are only specific application examples of the utility model, and do not constitute any limitation to the protection scope of the utility model. In addition to the above-mentioned embodiments, the utility model can also have other implementations. All technical solutions formed by equivalent replacement or equivalent transformation fall within the protection scope of the utility model.

Claims (10)

1. A composite light guide plate, comprising a light guide plate body (3') having a light incident side (31), a light exit surface (32) and a back surface (33), characterized in that: the light guide plate body (3') The light exit surface (32) and the back surface (33) respectively have a first slope (35) and a second slope (36) near the light incident side (31), and the first slope (35) and the second slope (36) are respectively It forms an included angle β with the horizontal plane of the light guide plate, 0<β<20°, and the back (33) of the light guide plate body has a composite reflection layer (37). 2. The composite light guide plate and its liquid crystal display module according to claim 1, characterized in that: the composite reflection layer (37) at least includes a reflection layer (371) and an appearance layer (372). 3. A composite light guide plate and its liquid crystal display module according to claim 2, characterized in that: the composite reflective layer (37) is sequentially formed from the back (33) of the light guide plate body (3') to the outside It is composed of an optical bonding layer (373), a reflective layer (371), and an appearance layer (372). 4. A composite light guide plate and its liquid crystal display module according to claim 2, characterized in that: the composite reflective layer (37) is sequentially formed by an optical bonding layer (373) from the back of the light guide plate body to the outside. , an optical coating (374), a reflective layer (371), and an appearance layer (372). 5. The composite light guide plate and its liquid crystal display module according to claim 4, characterized in that: the optical coating (374) is a low refractive index coating. 6. The composite light guide plate and its liquid crystal display module according to claim 3 or 4, characterized in that: the optical bonding layer (373) is transparent viscous optical glue. 7. The composite light guide plate and its liquid crystal display module according to claim 3 or 4, characterized in that: the reflective layer (371) is a PET foam layer. 8. The composite light guide plate and its liquid crystal display module according to claim 2, characterized in that: the reflective layer (371) is a highly reflective mirror film. 9. A composite light guide plate and its liquid crystal display module according to claim 1 or 2 or 3 or 4 or 8, characterized in that: the light guide plate body (3') is transparent such as PMMA, Glass, PC, etc. Material. 10. A liquid crystal display module according to claim 1, characterized in that it comprises the composite light guide plate according to claims 1-9.