TWI657290B - Backlight module and manufacture method thereof, and liquid crystal display device - Google Patents

Abstract

The invention provides a backlight module, which includes a plurality of optical films, and further includes a plurality of colloids, and the plurality of colloids are sequentially stacked, and each layer of the colloids bonds one optical film to fix the plurality of optical films. . The invention also provides a liquid crystal display device using the backlight module and a method for manufacturing the backlight module. The method for preparing the backlight module includes stacking a plurality of optical films; stacking a plurality of colloids; and bonding the stacked plurality of colloids to the plurality of optical films. The backlight module of the present invention uses multiple layers of colloids to bond different layers of optical films, the manufacturing process is simple, each optical film has good adhesion and fixation, and does not affect the optical performance between the optical films.

Description

Backlight module, preparation method thereof and liquid crystal display device

The invention relates to the field of preparation of backlight modules, in particular to the preparation of optical film adhesives for backlight modules, backlight modules and liquid crystal display devices using the adhesives.

As a backlight source, the backlight module is widely used in mobile phones, computers, various instruments and other devices with liquid crystal displays. The backlight module usually includes a plurality of optical films, light guide plates, reflection sheets, and the like. The plurality of optical films are thin and are stacked on the light guide plate and the reflection sheet. As shown in FIG. 1, the stacked plurality of optical films 10 are usually fixed in the plastic frame 14 only by attaching a layer of tape 12 at the top. However, this method cannot effectively fix the optical films 10 of each layer, which causes the lower-layer film to have a risk of shifting during use.

In view of this, it is necessary to provide a backlight module with a simple manufacturing process and a good adhesion and fixation of each optical film, a preparation method thereof, and a liquid crystal display device using the backlight module.

A backlight module includes a plurality of optical films, and further includes a plurality of colloids. The plurality of colloids are sequentially stacked, and each layer of the colloid is bonded to one of the optical films to fix the plurality of optical films.

Preferably, the first colloid of the multi-layer colloid covers the first optical film of the plurality of optical films, except for the N-th layer of colloids in sequence except the first layer of colloids and the N-1th optical of the plurality of optical films. The diaphragm is of equal thickness.

Preferably, one end of the plurality of optical films is stepped, and the multi-layered colloid is complementary to the stepped one end of the plurality of optical films facing the step of the plurality of optical films from the second layer of colloid, and includes a first layer of colloid The N-layer colloid is adhered to the surface of the N-th layer of the optical film to respectively bond the plurality of optical films.

Preferably, the multilayer colloids are alternately arranged in black and white.

Preferably, the first layer of colloid of the multilayer colloid is double-sided adhesive, and the Nth layer of colloid except for the first layer of colloid is double-sided adhesive or single-sided adhesive.

Preferably, the other end of the plurality of optical films is flush with the other end of the multi-layer colloid, and is accommodated in a plastic frame.

Preferably, the backlight module further includes a light guide plate and a reflection sheet disposed adjacent to the light guide plate, a plurality of optical films with the multi-layered colloid adhered to the light guide plate, and the light guide plate and the reflection sheet are accommodated. In the plastic frame, and the reflection sheet and the plastic frame are accommodated in a metal frame together.

A liquid crystal display device includes the backlight module.

A method for preparing a backlight module includes: stacking a plurality of optical films; stacking a plurality of colloids; and bonding the stacked plurality of colloids to the plurality of optical films.

Preferably, the first colloid of the multi-layer colloid covers the first optical film of the plurality of optical films, and the multi-layer colloid starts from the second layer of colloid and is complementary to one end of the plurality of optical films. The plurality of optical films are respectively bonded.

Preferably, the stacking of the multi-layer colloids is performed in a plurality of different stations and is cut with a flat knife or a rolling round knife.

Compared with the prior art, the backlight module of the present invention uses multiple layers of colloids to bond different layers of optical films, the manufacturing process is simple, each optical film has good adhesion and fixation, and does not affect the optical performance between the optical films.

200‧‧‧ backlight module

10,20‧‧‧Optical diaphragm

201‧‧‧ the first optical diaphragm

202‧‧‧The second optical diaphragm

203‧‧‧The third optical diaphragm

204‧‧‧The fourth optical diaphragm

25‧‧‧multi-layer colloid

251‧‧‧First Colloid

252‧‧‧Second layer of colloid

253‧‧‧The third layer of colloid

254‧‧‧The fourth layer of colloid

12‧‧‧Tape

30‧‧‧light guide

40‧‧‧Reflector

14,50‧‧‧plastic frame

60‧‧‧metal frame

FIG. 1 is a schematic structural diagram of a backlight module in the prior art.

FIG. 2 is a schematic structural diagram of a backlight module according to an embodiment of the present invention.

FIG. 3 is a schematic diagram of a formation process of a multilayer colloid according to an embodiment of the present invention.

The technical problem solved by the present invention stems from the fact that the plural optical films contained in the backlight module are usually only stacked in order, and pressed against the plastic frame of the backlight module, and only a layer of adhesive tape is fixed on the top. This method It is not able to effectively fix the optical films of each layer, which causes the lower-layer film to have a risk of shifting during use. The optical film is thinner, and each optical film may be shifted during use. It is necessary to consider between the optical films. The optical characteristics are such that no more adhesive can be inserted between the diaphragms. The present invention is based on finding the problem and designing the structural design and bonding method of the adhesive. For details, please refer to the backlight module embodiment below.

Please refer to FIG. 2 together. An embodiment of the present invention provides a backlight module 200 including a plurality of optical films 20, a multi-layered gel 25, a light guide plate 30, a reflective sheet 40, a plastic frame 50, and a metal frame 60.

The plurality of optical film sheets 20 are disposed on the light guide plate 30, and the light guide plate 30 is disposed on the reflection sheet 40. On the light guide plate 30, the plurality of optical film sheets 20 are sequentially stacked, the plurality of optical film sheets 20 are of different lengths, one end is aligned, and the other end is stepped. In this embodiment, the length of the optical film closest to the light guide plate 30 is the longest, and the length of the optical film in the direction away from the light guide plate 30 decreases in order.

In a direction away from the light guide plate 30, the first colloid 251 of the multilayer colloid 25 covers the first optical film 201 of the plurality of optical films 20, and the second colloid 252 of the multilayer colloid 25 and The first optical film 201 is the same thickness, the third colloid 253 of the multilayer colloid 25 is the same thickness as the second optical film 202 of the plurality of optical films 20, and the fourth colloid 254 is the third optical The diaphragm 203 is of equal thickness. If the colloid of more than four layers and the design of the thickness of the optical film are more than four, the Nth layer of the colloid except the first layer of colloid 251 and the N-1th optical film of the plurality of optical films are the same thickness. So that the N-th colloid of the multi-layer colloid and the N-1th optical film of the plurality of optical films are coplanarly disposed.

The first-layer gel 251 of the multi-layer gel 25 has the longest length and is used to further bond other components of the backlight module, such as the plastic frame 50. The multi-layered colloid 25 faces the stepped one end of the plurality of optical films 20 starting from the second-layered colloid 252 in a complementary step-like manner, that is, the length of the second-layered colloid 252 to the fourth-layered colloid 254 is closer to the The direction of the light guide plate 30 decreases in order.

The N-th colloid including the first-level colloid is directly adhered to the surface of the N-th optical film to respectively bond the plurality of optical films 20.

The first layer of colloid 251 of the multilayer colloid 25 uses double-sided adhesive, which can be used to further connect external components, such as a glass panel (not shown) of a liquid crystal display device. The second colloid 252 to the fourth colloid 254 of the multi-layer colloid 25 may be double-sided adhesive or single-sided adhesive. In the case of single-sided adhesive, only one side of the adhesive must be bonded to the surface of the corresponding optical film.

The multi-layered colloid 25 can use organic viscose, such as PET (Polyethylene Terephthalate, polyethylene terephthalate). If the first layer of colloid 251 is double-sided tape, it is preferably made of PET, and its flexibility can be better. The other second-layer colloid 252 to the fourth-layer colloid 254 may use the PET or some inorganic viscose material. The inorganic viscose material may be, for example, a high-temperature-resistant inorganic nano-composite water produced by the polycondensation reaction of the inorganic nano-material. Inorganic high temperature glue.

The multi-layered colloid 25 does not need to transmit light, and may be black, or alternately black and white for better identification.

The optical film 20, the multilayer colloid 25, the light guide plate 30, and the reflection sheet 40 are contained in a plastic frame 50, and the plastic frame 50 is contained in a metal frame 60.

The manufacturing method of the backlight module 200 includes the following steps: stacking a plurality of optical films; stacking a plurality of colloids; and bonding the stacked plurality of colloids to the plurality of optical films.

In the first step, all components of the backlight module are sequentially stacked and assembled, for example, a plurality of optical film sheets 20 are sequentially stacked on a light guide plate 30, wherein the light guide plate 30, the reflection sheet 40, and a plastic frame are sequentially stacked. 50 and metal frame 60 can be assembled in advance.

In the second step, as shown in FIG. 3, the stacking of the multilayer colloids is performed in order. The uppermost colloid 251 can be prepared first, and the second colloid is stacked next to the first colloid 251. 252, a third layer of colloid 253 is stacked on the second layer of colloid 252, and then a fourth layer of colloid 254 is stacked on the third layer of colloid 253. The colloids of each layer are cut from pre-prepared glue, which can be performed at a plurality of different stations, that is, each layer of colloids can be set at different stations according to the color, width, length and thickness requirements, and each station can be flat-blade Cutting, or rolling round knife to cut each layer of colloid. Flat or round knife is available These two types of die cutters are commonly used in the die cutting field, which can precisely cut the colloid and many membranes of the backlight module. The speed of the round knife can be faster than that of the flat knife in the mass production line.

In the third step, after the multilayer colloids 25 are stacked, they are adhered to the plurality of optical films 20 in one piece at a time. The multilayer colloids 25 and the optical films 20 are arranged in a stepwise complementary manner, and the N-th colloid is directly adhered. On the surface of the Nth layer of optical film, each layer of colloid can be directly attached and fixed corresponding to each layer of optical film, and there can be an appropriate gap between the end of the multilayer colloid 25 and the end of the facing optical film 20 The gaps can also be tightly connected.

In the backlight module provided by the embodiment of the present invention, the multilayer colloid 25 and the components of the backlight module are separately stacked and stacked. The stacked multilayer gel 25 directly bonds the plurality of optical films 20, and the manufacturing process is simple. Each optical film is adhered and fixed. Fortunately, the underlying optical film does not shift elements during use, and does not affect the optical performance between the optical films.

The backlight module 200 may be used in a liquid crystal display device. In cooperation with a light source, such as an LED or a CCFL, the light source may be disposed on a side of the light guide plate 30 of the backlight module 200.

Although the present invention has been disclosed as above by way of example, it is not intended to limit the present invention. Any person with ordinary knowledge in the technical field can make some changes and decorations without departing from the spirit and scope of the present invention. The protection scope of the present invention shall be determined by the scope of the attached patent application.

Claims (10)

A backlight module includes a plurality of optical films, and the improvement is that it further includes a plurality of colloids, and a plurality of the colloids are sequentially stacked, and each layer of the colloids bonds one optical film to fix the plurality of optical films. Sheet, one end of the plurality of optical films is stepped, and the multi-layered colloid is complementary stepped one end of the plurality of optical films facing the stepped one of the plurality of optical films. The backlight module according to claim 1, wherein: the first layer of the multi-layer colloid covers the first optical film of the plurality of optical films, and the N-th layer of colloid and The N-1th optical film of the plurality of optical films is of equal thickness. The backlight module according to claim 2, wherein the Nth layer of colloid including the first layer of colloid is adhered to the surface of the Nth layer of optical film to respectively bond the plurality of optical films. The backlight module according to claim 1, wherein the multilayer colloids are alternately arranged in black and white. The backlight module according to claim 3, wherein the first layer of colloid of the multi-layer colloid is double-sided adhesive, and the N-th layer of colloid in order except the first layer of colloid is double-sided adhesive or single-sided adhesive. The backlight module according to claim 3, wherein: the other end of the plurality of optical films is flush with the other end of the multi-layer colloid, and the backlight module further includes the last optical member of the plurality of optical films. The light guide plate in contact with the film and the reflection sheet disposed adjacent to the light guide plate, the plurality of optical film sheets, the multi-layer colloid, the light guide plate and the reflection sheet are contained in a plastic frame, and the plastic frame is contained in a metal Box. A liquid crystal display device includes a glass panel and the backlight module according to any one of claims 1-6, and the first layer of the multi-layer colloid is connected to the glass panel. A method for preparing a backlight module, comprising: stacking a plurality of optical films, one end of the plurality of optical films is stepped; stacking a plurality of colloids; and bonding the stacked plurality of colloids to the plurality of optical films The multi-layered colloid has a complementary step-like shape at one end of the step-like shape of the plurality of optical films from the second layer of colloid. The method for manufacturing a backlight module according to claim 8, wherein a first layer of the multi-layered colloid covers the first optical film of the plurality of optical films. The method for manufacturing a backlight module according to claim 8, wherein the stacking of the multi-layer colloids is performed at a plurality of different stations and is cut with a flat knife or a rolling round knife.