WO2022227226A1

WO2022227226A1 - Dimmable backlight module and backlight display apparatus

Info

Publication number: WO2022227226A1
Application number: PCT/CN2021/098247
Authority: WO
Inventors: 吴永隆; 毕重生
Original assignee: 太仓隆昇光电技术有限公司
Priority date: 2021-04-29
Filing date: 2021-06-04
Publication date: 2022-11-03
Also published as: CN113156688A

Abstract

The present disclosure provides a dimmable backlight module and a backlight display apparatus, and relates to the technical fields of skylights, panoramic sky screens and glass curtain walls in the automobile industry. The dimmable backlight module comprises a dimming assembly and a light source assembly. The dimming assembly comprises a PDLC film, a light guide plate and a PDLC film power supply. The PDLC film is attached to one side of the light guide plate, the PDLC film has an electrode side, and the electrode side is electrically connected to the PDLC film power supply. The light source assembly comprises a light-emitting element and an LED power supply. The light-emitting element is installed on one side or both sides of the light guide plate, and the light-emitting element is electrically connected to the LED power supply. The technical problems of existing LED backlight light sources in the prior art having relatively singular functions, an application field that is generally in the field of liquid crystal display, and less applicability in other fields are solved. Moreover, a technical effect which has a wide range of applications is achieved.

Description

Dimmable backlight module and backlight display device

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the priority of the Chinese Patent Application No. 2021104776789 and titled "Dimmable Backlight Module and Backlight Display Device" filed with the China Patent Office on April 29, 2021, the entire contents of which are incorporated herein by reference Applying.

technical field

The present disclosure relates to the technical fields of skylights, panoramic skylights and glass curtain walls in the automobile industry, and in particular, to a dimmable backlight module and a backlight display device.

Background technique

LED (Light Emitting Diode, light-emitting diode) backlight technology is widely used in the field of LCD TVs and panel lights. The design of the LED panel light mainly forms a uniform plane luminous effect after the light guide plate with high light transmittance. The illumination uniformity is good, the light is soft, comfortable and bright, which can effectively relieve eye fatigue. Generally, according to the position of the light source, LED backlights can be divided into edge-type backlights and direct-type backlights.

Among them, in the edge-type backlight technology, if the incident light encounters astigmatism points during the transmission of the light guide plate, diffuse reflection light will be formed at various angles. The propagation of light energy changes with the length of the light guide plate, so it is To ensure the uniformity of the outgoing light, the efficiency of the outgoing light should increase with the increase of the length of the light guide plate. The intensity of the diffuse reflection light is proportional to the intensity of the incident light at the position, and is proportional to the area of the scattering point. Therefore, during the propagation of the incident light, the intensity of the incident light is gradually weakened due to the diffuse reflection. Therefore, in order to ensure that the light on both sides of the light guide plate can be uniform, the diameter of the scattering point near the light source should be smaller, while the diameter at the other end is To be larger, in the design of the backlight, a major goal and challenge is to ensure that the light utilization efficiency is improved in the direction of vertical light propagation. By continuously and repeatedly adjusting the dot parameters for optimization, the final best brightness and uniformity can be obtained. .

The direct type backlight is composed of a reflective film, an LED lamp matrix, a diffuser film and a light-enhancing film. The LED matrix is arranged between the reflective film and the diffuser film. The volume of the backlight type LED is generally large, so it is suitable for large-sized products. Compared with the direct type backlight, the edge type backlight adds a light guide plate so that the LED matrix can be distributed on the side of the entire dimmable backlight module, thus greatly reducing the volume of the entire dimmable backlight module, so it can be applied For small and medium-sized products, this outside-in backlight has the advantage of being more energy-efficient than direct-type backlights.

However, the traditional LED backlight light source can only be used as a light source, and its function is relatively single, and its application field is generally in the field of liquid crystal display, and its application in other fields is less.

SUMMARY OF THE INVENTION

The present disclosure provides a dimmable backlight module and a backlight display device, so as to alleviate the relatively single function of the LED backlight light source in the prior art, and its application field is generally in the field of liquid crystal display, and the application in other fields is less. technical problem.

In some embodiments, the present disclosure provides a dimmable backlight module, the dimmable backlight module may include: a dimming component and a light source component.

In some embodiments, the dimming component may include a PDLC film (Polymer Dispersed Liquid Crystal, dimming film), a light guide plate and a PDLC film power supply, and the PDLC film may be attached to one side of the light guide plate, so that The PDLC film may have an electrode side, and the electrode side may be electrically connected to the PDLC film power supply.

In some embodiments, the light source assembly may include a light-emitting element and an LED power source, the light-emitting element may be installed on one side or both sides of the light guide plate, and the light-emitting element may be electrically connected to the LED power source.

According to the on-off states of the PDLC film power supply and the LED power supply, the dimmable backlight module can be switched between a transparent state, a fog state and a backlight state.

Optionally, the PDLC film may include a first base layer, a first conductive layer, a polymer liquid crystal layer, a second conductive layer and a second base layer which are arranged in sequence.

Optionally, both the first base layer and the second base layer may use a PET layer (polyethyleneterephthalate, polyethylene terephthalate); the first conductive layer and the second conductive layer may be All use an ITO layer (Indium tin oxide, indium tin oxide).

Optionally, the light guide plate can be made by laser etching or UV (UltraViolet, ultraviolet) screen printing.

And/or, the material of the light guide plate may be PC (Polycarbonate, polycarbonate), PMMA (acrylic or acrylic) or silica glass.

Optionally, the light-emitting element can be an LED light strip.

Optionally, the LED light strips can be arranged in one group, and one group of the LED light strips can be installed on one side of the light guide plate; The LED light strips can be respectively installed on opposite sides of the light guide plate.

Optionally, the dimmable backlight module may further include an outer frame.

The periphery of the light guide plate can be mounted on the outer frame.

Optionally, an optical plate may be provided on the side of the PDLC film away from the light guide plate, and the periphery of the optical plate may be mounted on the outer frame.

Optionally, the material of the optical plate can be PC, PMMA or silica glass.

Optionally, an optical plate may be provided on the side of the PDLC film facing away from the light guide plate.

In some embodiments, a hot melt adhesive layer may be attached between the PDLC film and the light guide plate and between the PDLC film and the optical plate. The optical plate and the two layers of the hot melt adhesive can form a pentagram structure.

Beneficial effects:

According to the dimmable backlight module provided by the present disclosure, the PDLC film can be attached to one side of the light guide plate, the PDLC film can have an electrode side, the electrode side can be electrically connected to the PDLC film power supply, the light-emitting element can be installed on the light guide plate, and The light-emitting element can be electrically connected with the LED power supply; in specific use, when the LED power supply is not powered on and the PDLC film power supply is powered on, the entire dimmable backlight module presents a transparent state; when the PDLC film power supply and the LED power supply are both powered off, The entire dimmable backlight module is in a fog state. According to the on-off state of the PDLC film power supply and the LED power supply, the dimmable backlight module can switch between the transparent state, the fog state and the backlight state. This transparent state The characteristics of flexible conversion between , fog state and backlight source state make this dimmable backlight module meet the needs of LCD TVs, skylights, panoramic sky screens and glass curtain walls in the automotive industry. In addition, when the PDLC film power supply is not powered and the LED power supply is powered, the PDLC film presents an opaque fog state. After the light emitted by the light-emitting element passes through the light guide plate, the light travel direction changes, and the light from the light guide plate passes through the PDLC. Due to the characteristics of the PDLC film (a large number of rod-shaped liquid crystal particles exist in the polymer liquid crystal layer), the light is reflected multiple times so that the light is evenly diffused in the entire plane. In this way, the point light source is converted into a surface. Therefore, the dimmable backlight module can also be used as a backlight light source.

In some embodiments, the present disclosure provides a backlight display device, and the backlight display device may include: the dimmable backlight module described in any one of the foregoing embodiments.

Beneficial effects:

The backlight display device provided by the present disclosure may include the aforementioned dimmable backlight module, thus, the beneficial effects and technical advantages that can be achieved by the backlight display device also include the beneficial effects and technologies that can be achieved by the dimmable backlight module. The advantages are not repeated here.

Description of drawings

In order to illustrate the specific embodiments of the present disclosure or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the specific embodiments or the prior art. Obviously, the accompanying drawings in the following description The drawings are some embodiments of the present disclosure. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings without creative efforts.

FIG. 1 is one of the disassembled schematic diagrams of the first embodiment of the dimmable backlight module provided by the embodiment of the present disclosure;

FIG. 2 is the second disassembled schematic diagram of the first embodiment of the dimmable backlight module provided by the embodiment of the present disclosure;

Fig. 3 is the structural representation of PDLC film;

Fig. 4 is the schematic diagram of illumination test area;

FIG. 5 is one of the disassembled schematic diagrams of the second embodiment of the dimmable backlight module provided by the embodiment of the present disclosure.

icon:

100-PDLC film; 110-electrode side; 120-first base layer; 130-first conductive layer; 140-polymer liquid crystal layer; 150-second conductive layer; 160-second base layer;

200-light guide plate;

300-PDLC film power supply;

400 - luminous parts;

500-LED power supply;

600-outer frame;

700 - Optical Board;

800 - Hot melt adhesive layer.

Detailed ways

In order to make the purposes, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present disclosure. Obviously, the described embodiments These are some, but not all, embodiments of the present disclosure. The components of the disclosed embodiments generally described and illustrated in the drawings herein may be arranged and designed in a variety of different configurations.

Therefore, the following detailed description of the embodiments of the disclosure provided in the accompanying drawings is not intended to limit the scope of the disclosure as claimed, but is merely representative of selected embodiments of the disclosure. Based on the embodiments in the present disclosure, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present disclosure.

It should be noted that like numerals and letters refer to like items in the following figures, so once an item is defined in one figure, it does not require further definition and explanation in subsequent figures.

In the description of the present disclosure, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship that the product of the invention is usually placed in use, only for the convenience of describing the present disclosure and simplifying the description, rather than indicating or implying References to devices or elements must have, be constructed, and operate in a particular orientation and are therefore not to be construed as limitations of the present disclosure. Furthermore, the terms "first", "second", "third", etc. are only used to differentiate the description and should not be construed as indicating or implying relative importance.

Furthermore, terms such as "horizontal", "vertical" etc. do not imply that a component is required to be absolutely horizontal or overhang, but rather may be slightly inclined. For example, "horizontal" only means that its direction is more horizontal than "vertical", it does not mean that the structure must be completely horizontal, but can be slightly inclined.

In the description of the present disclosure, it should also be noted that, unless otherwise expressly specified and limited, the terms "arranged", "installed", "connected" and "connected" should be understood in a broad sense, for example, it may be a fixed connection, It can also be a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or an indirect connection through an intermediate medium, or the internal communication between the two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present disclosure can be understood in specific situations.

Some embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The embodiments described below and features in the embodiments may be combined with each other without conflict.

Example 1

As shown in FIG. 1 and FIG. 2 , this embodiment can provide a dimmable backlight module, the dimmable backlight module can include a dimming component and a light source component; the dimming component can include a PDLC film 100, a light guide plate 200 and a PDLC film power source 300, the PDLC film 100 can be attached to one side of the light guide plate 200, the PDLC film 100 can have an electrode side 110, and the electrode side 110 can be electrically connected with the PDLC film power source 300; the light source assembly can include the light-emitting element 400 and In the LED power supply 500, the light-emitting element 400 can be installed on one side or both sides of the light guide plate 200, and the light-emitting element 400 can be electrically connected with the LED power supply 500; according to the on-off state of the PDLC film power supply 300 and the LED power supply 500, the light can be adjusted The backlight module can switch between transparent state, fog state and backlight state.

In the dimmable backlight module provided in this embodiment, the PDLC film 100 can be attached to one side of the light guide plate 200 , the PDLC film 100 can have an electrode side 110 , and the electrode side 110 can be electrically connected to the PDLC film power supply 300 , and the light-emitting element 400 It can be installed on the light guide plate 200, and the light-emitting element 400 can be electrically connected with the LED power supply 500; in specific use, when the PDLC film power supply 300 and the LED power supply 500 are powered on, the entire dimmable backlight module presents a transparent state; when the PDLC film power supply 300 and the LED power supply 500 are powered on When neither the film power supply 300 nor the LED power supply 500 is powered on, the entire dimmable backlight module is in a foggy state. Switching between fog state and backlight state, the flexible switching between transparent state, fog state and backlight state makes this dimmable backlight module suitable for LCD TVs, sunroofs in the automotive industry, panoramic canopies and The needs of glass curtain wall and other fields.

In addition, when the PDLC film power supply 300 does not supply power and the LED power supply 500 supplies power, the PDLC film 100 may present an opaque fog state. When the light coming out of 200 passes through the PDLC film 100, due to the characteristics of the PDLC film 100 (a large number of rod-shaped liquid crystal particles exist in the polymer liquid crystal layer 140), the light is reflected multiple times so that the light is uniformly diffused in the entire plane. In this way, the point light source is converted into a surface light source, so the dimmable backlight module can also be used as a backlight source.

Specifically, when the LED power source 500 is not energized and the PDLC film power source 300 is energized, the backlight module presents a transparent state; when the LED power source 500 is not energized and the PDLC film power source 300 is not energized, the backlight module exhibits a fog state. The flexible conversion between fog state and transparent state enables this dimmable backlight module to meet the needs of electronic curtains in the fields of skylights, panoramic skylights and glass curtain walls in the automotive industry; when the PDLC film power supply 300 is not powered, and the LED power supply 500 is powered on When the PDLC film 100 is in an opaque fog state, after the light emitted by the light-emitting elements 400 on the side passes through the light guide plate 200, the light travel direction changes. The optical axis of the molecules is in a disorderly arrangement, and the light is reflected for many times so that the light is evenly diffused in the entire PDLC film 100. In this way, the point light source is converted into a surface light source, so the dimmable backlight module It can also be used as a backlight source.

In this embodiment, the PDLC film 100 is used; the PDLC film 100, in addition to having the function of a diffuser, changes the exit angle of the incident light under the premise of ensuring high light transmittance, so that the light is refracted and scattered when it reaches the effective light-emitting surface, Thereby a good light diffusion effect is obtained. The feature of this material is that the high light transmittance enables the light to pass through the plate as much as possible to reach the effective light-emitting surface, avoid being reflected and absorbed, and form a white and bright fog-like turbid appearance on the effective light-emitting surface, thereby improving light efficiency and reducing energy consumption.

In addition, the PDLC film 100 has its own advantages. Because of the positive liquid crystal whose dielectric anisotropy (Δε) is greater than zero, when no electric field is applied (Off state), the liquid crystal molecules are arranged in disorder, and the incident light When passing through the PDLC film 100, multiple scattering occurs, and the display element is in an opaque state; when an electric field (On state) is applied, the liquid crystal molecules are arranged in parallel along the direction of the electric field. At this time, no=np, the incident light passes through the PDLC film 100 smoothly. The components are in a transparent state; based on this fact, the application field of the backlight module containing the PDLC film 100 can be expanded to the fields of sunroofs, panoramic sky screens and glass curtain walls in the automotive industry.

Specifically, the electrode side 110 may be electrically connected to the PDLC film power supply 300 through the first wire; the light emitting element 400 may be electrically connected to the LED power supply 500 through the second wire.

Optionally, as shown in FIG. 3 , the PDLC film 100 may include a first base layer 120 , a first conductive layer 130 , a polymer liquid crystal layer 140 , a second conductive layer 150 and a second base layer 160 which are arranged in sequence.

In some embodiments, both the first base layer 120 and the second base layer 160 may use a PET layer; both the first conductive layer 130 and the second conductive layer 150 may use an ITO layer.

In the traditional LED backlight module, the diffuser contains many granular objects, so the light received by the light guide plate can be diffused, so that the diffused light is more uniform. In this embodiment, the middle layer (polymer liquid crystal layer 140 ) of the PDLC film 100 is composed of many particulate polymer-liquid crystals, and the liquid crystal layer can effectively diffuse the light emitted by the light guide plate 200 . In addition, in the case of no electricity, the optical axis of the liquid crystal molecules is in a disorderly arrangement state, and at this time, the entire PDLC film 100 is in an optically hazy state. When power is supplied to the PDLC film 100, the optical axis directions of the nematic liquid crystal molecules in the PDLC film 100 are unified along the direction of the electric field, the ordinary refractive index of the liquid crystal particles and the refractive index of the matrix reach a certain degree of matching, and the light can pass through the matrix and appear in the direction of the electric field. transparent.

In some embodiments, the light guide plate 200 may be fabricated by laser etching or UV screen printing.

Optionally, the material of the light guide plate 200 can be PC, PMMA or silica glass.

In some embodiments, the light-emitting element 400 can use LED light strips; the LED light strips can be arranged in one group, and one group of LED light strips can be installed on one side of the light guide plate 200; or, the LED light strips can be arranged in two groups, The two groups of LED light strips can be respectively installed on opposite sides of the light guide plate 200 .

Wherein, both sets of LED light strips can be connected to the LED power supply 500; the light guide plate 200 and the two sets of LED light strips can constitute the light source part of the dimmable backlight module.

As shown in FIG. 1 or FIG. 2 , the dimmable backlight module may further include an outer frame 600; the periphery of the light guide plate 200 may be installed on the outer frame 600, and the aforementioned components are assembled together and installed on the outer frame with support and protection functions Above, it is convenient to disassemble and use the dimmable backlight module.

Optionally, the outer frame 600 may be an aluminum alloy frame.

Optionally, as shown in FIG. 2 , an optical plate 700 can be provided on the side of the PDLC film 100 away from the light guide plate 200 , and the periphery of the optical plate 700 can be installed on the outer frame 600 , and the optical plate 700 can protect the PDLC film 100 effect.

Optionally, the material of the optical plate 700 can be PC, PMMA or silica glass.

In other embodiments, referring to FIG. 5 , an optical plate 700 may be provided on the side of the PDLC film 100 away from the light guide plate 200 ; There are hot melt adhesive layers 800 , the PDLC film 100 , the light guide plate 200 , the optical plate 700 and the two layers of hot melt adhesive layers 800 , which can form a five-fold structure.

The hot melt adhesive layer 800 may be PVE (Polyvinyl chloride, polyvinyl chloride), PVB (polyvinyl butyral, polyvinyl butyral), EVA (Ethylene Vinyl Acetate, ethylene-vinyl acetate copolymer) or PU (polyurethane, any of polyurethane).

Embodiment 2

This embodiment also provides a backlight display device, which may include the aforementioned dimmable backlight module. The backlight display device provided in this embodiment may include the aforementioned dimmable backlight module. Therefore, the beneficial effects and technical advantages that can be achieved by the backlight display device also include the beneficial effects and technical advantages that the dimmable backlight module can achieve. The technical advantages are the same and will not be repeated here.

Wherein, the backlight display device may be a liquid crystal TV, a sunroof, a panoramic sunroof and a glass curtain wall in the automobile industry.

Comparative Example 1

This comparative example provides a dimmable backlight module, which is different from the first embodiment in that the PDLC film 100 is replaced with a diffusion film.

Comparative Example 2

This comparative example provides a dimmable backlight module, which is different from the first embodiment in that both the PDLC film and the diffusion film are omitted.

In order to compare the technical effects that can be achieved by each embodiment and the comparative example, the following experimental example is specially designed.

Experimental example 1

Record the thickness and sampling points of the films or light guide plates used in Example 1 and Comparative Examples 1-2, and use "Taiwan Taishi TES-1335 digital illuminometer" to measure the "light guide plate + PDLC" and "light guide plate" respectively. The three structures of "+diffusion film" and "light guide plate" were tested. The thickness of the liquid crystal coating of the PDLC dimming film was 9um and 13um. The material of the diffusion film was PC, PMMA, PS (Polystyrene, polystyrene) in sequence, and the illuminance was measured. .

Select 9 points on the surface of the plate-like structure to measure the illuminance. The schematic diagram of the test area is shown in Figure 4; the measurement results are shown in Table 1:

From the data in Table 1, it can be seen that under the same experimental conditions, the uniformity of illumination before and after the PDLC film of 13um is better than that of the PDLC film of 9um, and the diffusion film PMMA is better than the diffusion film PC is better than the diffusion film PS.

In summary, the dimmable backlight module of this embodiment has at least the following advantages:

1. The PDLC film 100 has the ability to diffuse light and can replace the diffusion film.

2. The thicker the liquid crystal thickness of the PDLC film 100, the better the uniform illumination.

3. The backlight module containing the PDLC film 100 has the ability to flexibly switch between the transparent state, the fog state and the backlight state, so the backlight module can also be used in the fields of sunroofs, panoramic sky screens and glass curtain walls in the automotive industry.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure, but not to limit them; although the present disclosure has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: The technical solutions described in the foregoing embodiments can still be modified, or some or all of the technical features thereof can be equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the technical solutions of the embodiments of the present disclosure. scope.

Industrial Applicability

According to the dimmable backlight module provided by the present disclosure, the PDLC film can be attached to one side of the light guide plate, the PDLC film can have an electrode side, the electrode side can be electrically connected to the PDLC film power supply, the light-emitting element can be installed on the light guide plate, and The light-emitting element and the LED power supply can be electrically connected; in specific use, when the LED power supply is not powered on and the PDLC film power supply is powered on, the entire dimmable backlight module presents a transparent state; when the PDLC film power supply and the LED power supply are both powered off, The entire dimmable backlight module is in a fog state. According to the on-off state of the PDLC film power supply and the LED power supply, the dimmable backlight module can switch between the transparent state, the fog state and the backlight state. This transparent state The characteristics of flexible conversion between , fog state and backlight source state make this dimmable backlight module meet the needs of LCD TVs, skylights, panoramic sky screens and glass curtain walls in the automotive industry.

Furthermore, it is understood that the PDLC films, LED power supplies, dimmable backlight modules, etc. of the present disclosure are reproducible and can be applied in a variety of industrial applications. For example, the PDLC film of the present disclosure can be applied in a backlight display device that needs to realize flexible switching between transparent state, haze state, and backlight state.

Claims

A dimmable backlight module is characterized by comprising: a dimming component and a light source component;

The dimming assembly includes a PDLC film (100), a light guide plate (200) and a PDLC film power source (300). The PDLC film (100) is attached to one side of the light guide plate (200), and the PDLC film (100) has an electrode side (110), and the electrode side (110) is electrically connected to the PDLC film power supply (300);

The light source assembly includes a light-emitting element (400) and an LED power supply (500), the light-emitting element (400) is installed on one side or both sides of the light guide plate (200), and the light-emitting element (400) is connected with the light-emitting element (400) the LED power supply (500) is electrically connected;

According to the on-off states of the PDLC film power supply (300) and the LED power supply (500), the dimmable backlight module can be switched between a transparent state, a fog state and a backlight state.
The dimmable backlight module according to claim 1, wherein the PDLC film (100) comprises a first base layer (120), a first conductive layer (130), and a polymer liquid crystal layer ( 140), a second conductive layer (150) and a second base layer (160).
The dimmable backlight module according to claim 2, wherein the first base layer (120) and the second base layer (160) are both made of PET layers;

Both the first conductive layer (130) and the second conductive layer (150) use an ITO layer.
The dimmable backlight module according to any one of claims 1 to 3, wherein the light guide plate (200) is made by laser etching or UV screen printing; and/or, the The material of the light guide plate (200) is PC, PMMA or silica glass.
The dimmable backlight module according to any one of claims 1 to 3, wherein the light-emitting element (400) adopts an LED light strip;

The LED light strips are arranged in one group, and one group of the LED light strips is installed on one side of the light guide plate (200); or, the LED light strips are arranged in two groups, and the two groups of the LED light strips are respectively Installed on opposite sides of the light guide plate (200).
The dimmable backlight module according to any one of claims 1 to 5, wherein the dimmable backlight module further comprises an outer frame (600);

The periphery of the light guide plate (200) is mounted on the outer frame (600).
The dimmable backlight module according to claim 6, characterized in that, an optical plate (700) is provided on the side of the PDLC film (100) facing away from the light guide plate (200), and the optical plate (700) ) is mounted on the outer frame (600).
The dimmable backlight module according to claim 7, wherein the material of the optical plate (700) is PC, PMMA or silica glass.
The dimmable backlight module according to claim 1, wherein an optical plate (700) is provided on the side of the PDLC film (100) facing away from the light guide plate (200);

A hot melt adhesive layer (800) is attached between the PDLC film (100) and the light guide plate (200) and between the PDLC film (100) and the optical plate (700). The film (100), the light guide plate (200), the optical plate (700) and the two layers of the hot-melt adhesive layer (800) form a pentagram structure.
A backlight display device, comprising: the dimmable backlight module according to any one of claims 1 to 9.