TWI382243B - Back light module and liquid crystal display device - Google Patents

Description

Backlight module and liquid crystal display device

The present invention relates to a backlight module and a display device, and more particularly to a backlight module having good light uniformity and a liquid crystal display device using the backlight module as a display light source.

The liquid crystal display panel of the liquid crystal display does not have the function of emitting light. Therefore, the surface light source required for the liquid crystal display panel must be provided by an external light source, such as a backlight module, to achieve the function of displaying the screen. Therefore, the light output quality of the backlight module is closely related to the display quality of the liquid crystal display.

Generally speaking, cold cathode fluorescent tubes are commonly used as illumination sources in backlight modules, so the illumination quality of cold cathode fluorescent tubes can be said to be an important factor affecting the quality of the surface light source provided by the backlight module. The two ends of the cold cathode fluorescent lamp are respectively provided with a high voltage electrode end and a low voltage electrode end. When the cold cathode fluorescent lamp is in operation, the current will gradually leak from the high voltage electrode end to the low voltage electrode end, which will cause the luminance of the cold cathode fluorescent lamp to be relatively bright at the high voltage electrode end. The direction of the low voltage electrode end is relatively dark. Especially after the cold cathode fluorescent lamp is opened for a period of time, the influence of the leakage current phenomenon will gradually become significant.

In addition, when a cold cathode fluorescent lamp is fabricated, the phosphor layer formed inside the tube by the siphon principle is often not uniformly distributed in the tube. Usually the phosphor layer in the center of the tube will be thicker and the phosphor layer on both ends of the tube will be thinner. Therefore, when the cold cathode fluorescent lamp is in operation, the ends of the cold cathode fluorescent lamp tend to Presents a lower brightness than the center. Based on the above factors, the cold cathode fluorescent lamp is close to the low voltage electrode end, and its luminance is relatively lower than other regions.

In other words, the luminance of the cold cathode fluorescent lamp is not uniform. Therefore, when the cold cathode fluorescent lamp is used as the light source, the illuminance uniformity of the backlight module is not ideal. In order to improve the uniformity of the light output of the backlight module, a high-quality cold cathode fluorescent lamp with a relatively uniform luminance can be used or a suitable optical film can be disposed for compensation, and the backlight can be adjusted even by the adjustment of the control circuit. The group has a better uniformity of light output.

However, the use of a uniform cathode fluorescent cathode fluorescent lamp and the arrangement of an optical film requires a relatively high cost, and the adjustment of the control circuit requires a more complicated technique. Therefore, how to improve the uniformity of light output of the backlight module without increasing the cost and technical complexity is a key point in the manufacture and design of the backlight module.

The invention provides a backlight module, which is provided before the cost is low and the production steps are simple, and the uniformity of the light output of the backlight module is improved.

The present invention further provides a liquid crystal display device which uses a backlight module with good light uniformity as a display light source, and thus has a good display effect.

The invention provides a backlight module comprising a light box and at least one light tube. The light box has a patterned reflective structure to define a first zone and a second zone having different reflectivity. The lamp is arranged in the light box. The lamp tube has a high voltage electrode end and a low voltage electrode end, and the second area is disposed corresponding to the high voltage electrode end, and the first area is disposed corresponding to the low voltage electrode end. Reflectivity of the first zone Higher than the reflectivity of the second zone.

The present invention further provides a liquid crystal display device including a backlight module and a liquid crystal display panel. The liquid crystal display panel is disposed above the backlight module. In addition, the backlight module includes a light box and at least one light tube. The light box has a patterned reflective structure to define a first zone and a second zone having different reflectivities. The lamp is arranged in the light box. In addition, the lamp tube has a high voltage electrode end and a low voltage electrode end, and the second area is disposed corresponding to the high voltage electrode end, and the first area is disposed corresponding to the low voltage electrode end. The reflectance of the first zone is higher than the reflectivity of the second zone.

In an embodiment of the invention, the light box comprises a box body having a bottom wall and a plurality of side walls, and the patterned reflective structure is located on at least one of the bottom wall and the side wall of the box body to define The first zone and the second zone.

In an embodiment of the invention, the patterned reflective structure is, for example, at least one patterned reflective sheet, wherein each patterned reflective sheet has a different reflectivity. Portions of each of the patterned reflective sheets overlap each other, and the exposed patterned reflective sheet and a portion of the light box define a first region and a second region. The backlight module further includes an adhesive layer disposed between the patterned reflective sheet and the case. For example, the adhesive layer includes a double-sided tape, a heat-curable adhesive or a photo-curable adhesive.

In an embodiment of the invention, the patterned reflective structure is at least one patterned reflective film to define reflective regions of different reflectivity. In addition, each patterned reflective film has a different reflectivity.

In an embodiment of the invention, the patterned reflective structure is a white reflective housing disposed in the housing and the housing and the white reflective housing The reflectivity is different. In addition, the white reflective housing has at least one opening, and the opening exposes a portion of the housing to define a first zone and a second zone.

In an embodiment of the invention, the light box further has a third zone, the third zone being located between the first zone and the second zone, and the reflectivity of the third zone is lower than the reflectivity of the second zone.

In an embodiment of the invention, the backlight module further includes an optical film set disposed on the light box. In practice, the optical film set includes a diffusion sheet, a brightness enhancement sheet, a brightness enhancement sheet, or a combination thereof.

In the backlight module of the present invention, the patterned reflective structure defines reflective regions having different light reflectivities. A region having a weak light source luminance is disposed corresponding to a patterned reflection structure having a high light reflectance, and a region having a strong light source luminance is disposed corresponding to a patterned reflection structure having a low light reflectance. In this way, the backlight module of the present invention can have good uniformity of light output. At the same time, the patterned reflective structure of the present invention is completed by a simple process such as attaching a reflective sheet, forming an opening in a box of a light box, or coating a reflective film. Therefore, the present invention has the advantages of simple process and low production cost. .

The above and other objects, features and advantages of the present invention will become more <RTIgt;

In order to improve the uniformity of the light output of the backlight module, the present invention proposes to perform luminance compensation on different luminance regions in the backlight module by using reflective regions with different light reflectances. Therefore, the uniformity of the light output of the backlight module is not required Compensation can be obtained with expensive optical films or high quality lamps, even with circuit adjustments. The embodiments of the backlight module of the present invention will be described below for the purpose of illustration. However, those skilled in the art to which the present invention pertains are not limited to the embodiments.

FIG. 1 is a schematic diagram of a backlight module according to an embodiment of the invention. Referring to FIG. 1 , the backlight module 100 includes a light box 110 , at least one light source 120 , and a plurality of reflective layers 130 . The light box 110 has a light exit opening 112 and a bottom portion 114 opposite the light exit opening 112. The light source 120 is disposed in the light box 110. In addition, the plurality of reflective layers 130 are disposed on the bottom wall 114 of the light box 110 , and the reflective layer 130 is adapted to reflect the light emitted by the light source 120 to the light exit opening 112 .

In fact, since the luminance of the light source 120 is not easily achieved to a completely uniform degree, when the backlight module 100 is lit, the luminance emitted by the light source 120 in the light box 110 does not coincide. Therefore, in the present embodiment, a plurality of luminance regions P are defined in the light box 110, wherein the regions where the light source 120 emits relatively bright light and the regions where the light source 120 emits relatively dark light may be defined as different luminance regions P, respectively. In other words, the plurality of luminance regions P defined in the light box 110 are divided according to, for example, the luminance of the light source 120 disposed in the light box 110, and the reflective layers 130 corresponding to the respective luminance regions P have different light reflectances.

In the present embodiment, the light source 120 is composed, for example, of a plurality of cold cathode fluorescent tubes substantially parallel to each other (as shown in FIG. 1). Each of the cold cathode fluorescent lamps has a high voltage electrode end 122 and a low voltage electrode end 124. At the same time, the high voltage electrode ends 122 of the light sources 120 shown in FIG. 1 are all disposed on the same side, and the low voltage electrode ends 124 are disposed on the opposite side. Prior art It can be seen that when the cold cathode fluorescent lamp is in operation, the current gradually flows from the high voltage electrode end 122 to the low voltage electrode end 124, so that the brightness of the light source 120 corresponding to the low voltage electrode end 124 is relatively low. Here, a region of the light box 110 corresponding to the light source 120 having a higher luminance of illumination may be defined as the first luminance region P1. In addition, an area of the light box 110 corresponding to the lower luminance of the light source 120, that is, an area corresponding to the low voltage electrode end 124, may be defined as the second luminance area P2.

In order to achieve a certain uniformity of the light uniformity of the backlight module 100, it is necessary to make the first luminance region P1 and the second luminance region P2 exhibit substantially the same luminance. Therefore, in the present embodiment, the reflective layer 130 of different light reflectance is disposed at the bottom 144 of the light box 110, wherein the first reflective layer 132 having a small light reflectance is disposed in the first luminance region P1, and the light reflectance is large. The second reflective layer 134 is correspondingly disposed in the second luminance region P2. In fact, these reflective layers 130 of different reflectivity may also be defined herein as a patterned reflective structure (not labeled) to provide different degrees of reflection in different regions of the backlight module 100, respectively. In other words, the patterned reflective structure (not shown) is disposed in the backlight module 100 to define a plurality of reflective regions (not labeled) having different reflectivities. Therefore, the present invention does not limit the arrangement of the patterned reflective structure (not shown) in the backlight module 100.

When the backlight module 100 is illuminated, the luminance exhibited by the first luminance region P1 includes the sum of the luminance of the light emitted by the light source 120 in the first luminance region P1 and the light reflected by the first reflective layer 132. Similarly, the luminance exhibited by the second luminance region P2 is the total luminance of the light emitted by the light source 120 in the second luminance region P2 and the light reflected by the second reflective layer 134. with. Although the light source 120 itself has a relatively dark luminance corresponding to the second luminance region P2, the second reflective layer 134 has a large light reflectivity, so that the light emitted by the light source 120 in the second luminance region P2 can be more It is efficiently reflected to the light exit opening 112. In contrast, since the luminance of the light source corresponding to the first luminance region P1 is bright, the reflective layer 132 having a light reflectance lower than that of the reflective layer 134 can be used.

Therefore, after the compensation of the first reflective layer 132 and the second reflective layer 134 having different light reflectances, the luminances of the first luminance region P1 and the second luminance region P2 can be substantially the same, thereby allowing the backlight module 100 to be Has a good uniformity of light output.

In addition, when the high voltage electrode ends 122 of the respective light sources 120 are not necessarily located on the same side, that is, the high voltage electrode ends 122 of the partial light sources 120 are located on the left side and the high voltage electrode ends 122 of the other partial light sources 120 are located on the right side, A plurality of first luminance regions P1 and a plurality of second luminance regions P2 are defined in the light box 110 of the high voltage electrode end 122 and the low voltage electrode end 124 of the light source 120. At this time, the first reflective layer 132 may be disposed in each of the first luminance regions P1, and the second reflective layer 134 may be disposed corresponding to each of the second luminance regions P2.

In addition, the luminance of the cold cathode fluorescent lamp exhibits different luminances in different regions as the use time increases and the temperature inside the light box 110 changes. Therefore, the plurality of luminance regions P can also be defined according to temperature changes that may occur when the backlight module 100 is used. In other words, the different luminance regions P do not necessarily have to be divided corresponding to the high voltage electrode terminal 122 or the low voltage electrode terminal 124 of the light source 120.

Of course, the division of the luminance region P is not limited to being divided into only the first luminance region P1 and the second luminance region P2. In different backlight module 100 designs, the third and fourth colors may be further defined in the light box 110. Fifth...etc. A plurality of luminance regions P. Further, when the plurality of luminance regions P of the third, fourth, fifth, etc. are further defined in the light box 110, the reflectance of the reflective layer 130 corresponding to each of the luminance regions P and the light source in each of the luminance regions P The 120 luminosity distribution is inversely proportional. That is to say, in the luminance region P in which the light source 120 has a relatively low luminance, the reflective layer 130 having a high light reflectance should be disposed correspondingly. Conversely, a reflective layer 130 having a lower light reflectance should be disposed. In this way, the backlight module 100 can have good uniformity of light output.

2 is a cross-sectional view of the backlight module of FIG. 1 along a direction in which the light source extends. Referring to FIG. 2, the reflective layer 130 may be composed of a plurality of reflective sheets having different light reflectivities, and each of the reflective sheets may be adhered to the bottom 114 of the light box 110 by the adhesive layer 140. The adhesive layer 140 may be a double-sided tape, a heat-curable adhesive or a photo-curable adhesive. In other embodiments, there may be partial regions between the reflective sheets that overlap each other. Of course, the reflective layer 130 is not limited to being composed of a reflective sheet. For example, the reflective layer 130 may also be composed of a plurality of reflective films of different light reflectivities. When the reflective layer 130 is composed of a plurality of reflective films, the reflective layer 130 is formed by, for example, forming a material of different light reflectivity in the bottom portion 114 of the light box 110 by coating. In addition, the optical film set 150 may be disposed on the light box 110 to improve the light output quality of the backlight module 100. The optical film set 150 includes a diffusion sheet, a brightness enhancement sheet, or a combination thereof.

Generally, in order to know the uniformity of the light output of the backlight module 100, The backlight module 100 divides a plurality of test areas, and converts the ratio of the minimum luminance to the maximum luminance measured by each test area into a percentage value, which can be expressed as the uniformity of the light output. Wherein, if the backlight module is divided into 13 test areas, the uniformity of the light output must be greater than 75% to meet the detection specifications, and the division manner of the 13 test areas is shown in FIGS. 1 to 13 of FIG. 3A.

3B and 3C show the luminance test results of the conventional backlight module and the backlight module 100 of the present invention, respectively. Referring to FIG. 3B, it is found from the actual measurement results that the brightness of the conventional backlight module in the low-voltage electrode end region of the corresponding light source, for example, the area corresponding to the test area 6, 9, 11 is relatively small, and the value thereof is relatively small. They are 5662, 6070 and 5640 respectively. Moreover, the uniformity of the light output of the conventional backlight module is (5640/8019)×100%=70%. Next, referring to FIG. 3C, under the same light source and light box design, light reflection is arranged in the backlight module 100 at the low voltage electrode end 124 region of the corresponding light source 120, that is, on one side corresponding to the test areas 6, 9, and 11. A larger reflective layer 134. The actual measurement results show that the luminances of the backlight module 100 corresponding to the low-voltage electrode end 124 are 6350, 6500, and 6300, respectively, which are larger than the results measured by the conventional backlight module in the same area. Moreover, the uniformity of the light output of the backlight module 100 is (6300/8019)×100%=78.5%. Therefore, the design of the backlight module 100 can effectively improve the problem of poor uniformity of the light output of the conventional backlight module. Specifically, the process of using the reflective sheet attaching or the reflective film coating of the backlight module 100 for different reflectances can improve the uniformity of the light output of the backlight module, so the cost required is lower than other improvement methods. The process is also quite simple.

The present invention further proposes a liquid crystal display device as shown in FIG. Referring to FIG. 4 , the backlight module 100 described above is applied to the liquid crystal display device 400 , and a liquid crystal display panel 410 is disposed above the backlight module 100 . Since the backlight module 100 provides uniform brightness to the liquid crystal display panel 410 to display an image, the liquid crystal display device 400 can have a good display effect.

Of course, the present invention is not limited thereto. In order to improve the display effect of the liquid crystal display device 400, the backlight module 100 may have other design methods. FIG. 5A is a schematic diagram of a backlight module according to another embodiment of the present invention, and FIG. 5B is a cross-sectional view of the backlight module of FIG. 5A along a direction in which the lamp tube extends. Referring to FIG. 5A and FIG. 5B , the backlight module 500 includes a light box 510 and a light tube 520 disposed in the light box 510 . The light box 510 includes a box 512 and a patterned reflective structure 530 on the box 512 . The patterned reflective structure 530 includes three patterned reflective sheets 532, 534, and 536 having different reflectivities to define a first region R1, a second region R2, and a third region R3, respectively.

The tube 520 is, for example, a cold cathode fluorescent tube, and the tube 520 exhibits a higher luminance at the high voltage electrode end 522 and a lower luminance at the low voltage electrode end 524. Therefore, in order to make the backlight module 500 have good uniformity of light output, the reflectance provided by the reflective plate 532 may be greater than the reflectance provided by the reflective plate 536. In other words, the reflectance of the first region R1 is higher than the reflectance of the reflective region R3. In addition, when the backlight module 500 is actually applied to a liquid crystal display device, it is disposed in a direct type. In addition, when the backlight module 500 is illuminated, the temperature distribution inside the light box 510 is not uniform, for example, the temperature of the high voltage end is high, and the high temperature causes the brightness of the tube to decrease, resulting in the brightness of the high voltage end being lower than that of the central brightness tube 520. Presented in the central area of light box 510 The brightness may be larger. Therefore, the reflectance of the patterned reflective sheet 534 in this embodiment is, for example, smaller than that of the patterned reflective sheet 536 to improve the uniformity of the light output of the backlight module 500. That is, the reflectance of the second region R2 is smaller than the reflectance of the first region R1 and the third region R3.

Referring to FIG. 5B, the case 512 of the light box 510 has, for example, a bottom wall 514 and a plurality of side walls 516, wherein the case 512 of the present embodiment is made of, for example, a white reflective plate. Furthermore, the patterned reflective structure 530 is here disposed on the bottom wall 514 of the case 512. Therefore, the side wall 516 of the case 512 will be exposed, and the reflectivity of the case 512 itself will also affect the reflected light. In other embodiments, the patterned reflective structure 530 can also be disposed on the sidewall 516 of the housing 512 or simultaneously disposed on the sidewall 516 and the bottom wall 514 to define regions R1 R R4 of different reflectivity. In addition, an optical film 150 may be disposed above the backlight module 500.

In fact, the patterned reflective sheets 532, 534, and 536 have different reflectivities. Meanwhile, in order to prevent the gap between the patterned reflective sheets 532, 534, and 536 from affecting the reflectance distribution of each region in the backlight module 500, partial regions of the patterned reflective sheets 532, 534, and 536 overlap each other, for example. At this time, the exposed patterned reflection sheets 532, 534, and 536 and the side walls 516 of the case 512 define regions R1 to R4 having different reflectances, respectively. More specifically, the patterned reflective sheets 532, 534, and 536 are attached to the case 512 by an adhesive layer 504. The adhesive layer 504 includes a double-sided tape, a heat-curable adhesive or a photo-curable adhesive.

Of course, the design layout of the patterned reflective structure 530 of this embodiment may also be replaced by the patterned reflective film 532, 534. And 536. That is, the present invention does not exclude the use of a patterned reflective film (not shown) of different reflectances to define a plurality of reflective regions R1 R R4 in the backlight module 500.

FIG. 6 is a schematic diagram of a backlight module according to still another embodiment of the present invention. Referring to FIG. 6 , the backlight module 600 is similar to the backlight module 500 described above, wherein the design of the patterned reflective sheets 632 and 634A-D is different from the patterned reflective structure 530 described above. Since the luminance of the lamp 520 itself is not uniform, and the backlight module 600 is turned on, the temperature distribution in the casing 512 also affects the luminous efficacy of each of the lamps 520. Therefore, in this embodiment, it is proposed that the patterned reflection sheets 634A-D having a high reflectance are respectively disposed in the four corners which may be dark in the casing 512.

The patterned reflective sheets 634A-D can have substantially different reflectivities. For example, the patterned reflective sheets 634A and 634D are disposed at the high voltage electrode end 522 of the bulb 520, and the patterned reflective sheets 634B and 634C are disposed at the low voltage electrode end 524 of the bulb 520. Thus, patterned reflective sheets 634A and 634D can provide relatively low reflectivity, while patterned reflective sheets 634B and 634C should provide relatively high reflectivity. In addition, the patterned reflective sheets 634A-D located at the corners may also be patterned reflective films of different reflectivity, etc., which are used to define a plurality of reflective regions R1 R R5 of different reflectances and have a good backlight module 600. The light is uniform.

7A and FIG. 7B are respectively a top view and a cross-sectional view of a backlight module according to still another embodiment of the present invention. Referring to FIG. 7A and FIG. 7B simultaneously, the backlight module 700 includes a white reflective housing 712 , a plurality of lamps 720 , and a housing 740 . The box 740 covers a part of the white reflective housing 712, and the tube The 720 is disposed in the white reflective housing 712. In essence, the housing 740 and the white reflective housing 712 together form a light box (not labeled) that provides different reflectivities in different areas. In addition, the two ends of the lamp tube 720 are a high voltage electrode end 722 and a low voltage electrode end 724, respectively. The white reflective housing 712 has a plurality of openings 714A, 714B, and the openings 714A, 714B expose a portion of the housing 740 to define a plurality of first and second regions R1 and R2 of different reflectivities. In practice, the area in which openings 714A, 714B are located defines two first zones R1, while the locations of other portions of white reflective housing 712 define a second zone R2. The second zone R2 is, for example, located between the two first zones R1.

The material of the box 740 is generally made of metal, and the white reflective housing 712 is made of white plastic material, and the reflectivity of the white reflective housing 712 can be higher than that provided by the box 740. high. That is, the openings 714A, 714B may define a first region R1 having a lower reflectance, and the region where the white reflective casing 712 is located define a second region R2 having a higher reflectance. In addition, the illuminating luminance of the lamp tube 720 corresponding to the high voltage electrode end 722 is higher and the illuminating luminance corresponding to the low voltage electrode end 724 is lower. Therefore, in this embodiment, for example, the large-area idle port 714A is disposed corresponding to the high-voltage electrode end 722, and the relatively small-area opening 714B is disposed corresponding to the low-voltage electrode end 724.

The positions of the openings 714A, 714B described above can be set according to actual needs. For example, the openings 714A, 714B may be correspondingly disposed on the side of the white reflective housing 712, or in the central portion of the white reflective housing 712 corresponding to the bottom of the housing 740.

Because the arrangement position and the size of the openings 714A, 714B can be There are various variations with the design of different backlight modules 700. Therefore, this embodiment proposes that the overall reflectance of each region of the backlight module 700 is adjusted by the openings 714A, 714B of different area sizes. Therefore, the backlight module 700 can have good uniformity of light output, and the backlight module 700 can also improve the display quality of the liquid crystal display device when applied to the liquid crystal display device. In essence, the backlight modules 500, 600, and 700 proposed in the above embodiments can be applied to the liquid crystal display device shown in FIG. 4 or other electronic products having high requirements for uniformity of light output. In addition, the design of the openings 714A, 714B in this embodiment can be configured in combination with the patterned reflective sheet or the patterned reflective film in the foregoing embodiment, so that the backlight module 700 has a uniform light-emitting effect.

In summary, the backlight module and the liquid crystal display device of the present invention have at least the advantages described below. The invention utilizes different patterned reflection structures to provide different light reflectances to compensate for uneven illumination of the light source, so that the backlight module has good uniformity of light output. Since the backlight module of the present invention has good uniformity of light output, it can provide a good quality surface light source when applied to a liquid crystal display device, and the liquid crystal display device has a good display effect. Furthermore, in the backlight module of the present invention, a process of attaching a simple reflective sheet, forming an opening in a light box, or coating a reflective film to form a patterned reflective structure, and thus the backlight module and the liquid crystal display of the present invention The manufacturing cost of the device is lower than other compensation methods and the process steps are simple.

Although the present invention has been disclosed in the above preferred embodiments, it is not intended to limit the invention, and any one of ordinary skill in the art can make some modifications and refinements without departing from the spirit and scope of the invention. , Therefore, the scope of the invention is defined by the scope of the appended claims.

100, 500, 600, 700‧‧‧ backlight module

110, 510‧‧‧ light box

112‧‧‧Light outlet

114, 514‧‧‧ bottom wall

120‧‧‧Light source

122, 522, 722‧‧‧ high voltage electrode end

124, 524, 724‧‧‧ low-voltage electrode end

130‧‧‧reflective layer

132‧‧‧First reflective layer

134‧‧‧second reflective layer

140‧‧‧Adhesive layer

150‧‧‧Optical diaphragm group

400‧‧‧Liquid crystal display device

410‧‧‧LCD panel

512, 740‧‧‧ cabinet

516‧‧‧ side wall

520, 720‧‧‧ lamps

530‧‧‧patterned reflective structure

532, 534, 536, 632, 634A~D‧‧‧ patterned reflective sheet

712‧‧‧White reflective housing

714A, 714B‧‧‧ openings

P‧‧‧Huangdu District

P1‧‧‧First Brightness Zone

P2‧‧‧second brightness zone

R1, R2, R3, R4, R5‧‧‧ areas

FIG. 1 is a schematic diagram of a backlight module according to an embodiment of the invention.

2 is a cross-sectional view of the backlight module of FIG. 1 along a direction in which the light source extends.

FIG. 3A is a schematic diagram of the test area division when the backlight module performs the luminance test.

FIG. 3B is a result of performing a luminance test on a conventional backlight module.

FIG. 3C is a result of performing a luminance test on the backlight module 100 of the present invention.

4 is a schematic view of a liquid crystal display device according to an embodiment of the present invention.

FIG. 5A is a schematic diagram of a backlight module according to another embodiment of the present invention.

FIG. 5B is a cross-sectional view of the backlight module of FIG. 5A along the extending direction of the lamp tube.

FIG. 6 is a schematic diagram of a backlight module according to still another embodiment of the present invention.

7A and FIG. 7B are respectively a top view and a cross-sectional view of a backlight module according to still another embodiment of the present invention.

100‧‧‧Backlight module

110‧‧‧Lightbox

112‧‧‧Light outlet

114‧‧‧ bottom

120‧‧‧Light source

122‧‧‧High voltage electrode end

124‧‧‧Low-voltage electrode end

130‧‧‧reflective layer

132‧‧‧First reflective layer

134‧‧‧second reflective layer

P‧‧‧Huangdu District

P1‧‧‧First Brightness Zone

P2‧‧‧second brightness zone

Claims (32)

A backlight module includes: a light box, comprising a box body, the box body having a bottom wall and a plurality of side walls; a patterned reflective structure on the bottom wall of the box body and at least one of the side walls The patterned reflective structure is a white reflective housing disposed in the housing, and the housing has a different reflectivity from the white reflective housing. The white reflective housing has at least one opening, and the opening exposes a portion The box body defines a first area and a second area having different reflectances; and at least one light tube is disposed in the light box, the light tube has a high voltage electrode end and a low voltage electrode end, The second region is disposed at the end of the high voltage electrode, and the first region is disposed at the end of the low voltage electrode, and the reflectance of the first region is higher than the reflectivity of the second region. The backlight module of claim 1, further comprising an adhesive layer disposed between the patterned reflective sheet and the housing. The backlight module of claim 2, wherein the adhesive layer comprises a double-sided adhesive, a heat-curable adhesive or a photo-curable adhesive. The backlight module of claim 1, further comprising an optical film set disposed on the light box. The backlight module of claim 4, wherein the optical film set comprises a diffusion sheet, a brightness enhancement sheet or a combination thereof. A liquid crystal display device comprising: a backlight module, comprising: a light box, comprising a box body, the box body having a bottom wall and a plurality of side walls; a patterned reflective structure on the bottom wall of the case and at least one of the side walls, the patterned reflective structure being a white reflective housing disposed in the case, and the case and the white reflection The reflectivity of the housing is different, the white reflective housing has at least one opening, and the opening exposes a portion of the box to define a first region and a second region having different reflectivities; and at least one tube Disposed in the light box, the lamp tube has a high voltage electrode end and a low voltage electrode end, the second area is corresponding to the high voltage electrode end, and the first area is corresponding to the low voltage electrode end, And the reflectivity of the first region is higher than the reflectivity of the second region; and a liquid crystal display panel disposed above the backlight module. The liquid crystal display device of claim 6, wherein the backlight module further comprises an adhesive layer disposed between the patterned reflective sheet and the housing. The liquid crystal display device of claim 7, wherein the adhesive layer comprises a double-sided adhesive, a heat-curable adhesive or a photo-curable adhesive. The liquid crystal display device of claim 6, further comprising an optical film set disposed on the light box. The liquid crystal display device of claim 9, wherein the optical film set comprises a diffusion sheet, a brightness enhancement sheet or a combination thereof. A backlight module includes: a light box having a patterned reflective structure to define a first region, a second region, and a third region having different reflectivities, wherein the third region is located in the first region And between the second districts; At least one light tube disposed in the light box, the light tube has a high voltage electrode end and a low voltage electrode end, the second area corresponding to the high voltage electrode end, and the first area corresponding to the low voltage The extreme portion is disposed, and the reflectivity of the first region is higher than the reflectivity of the second region, and the reflectance of the third region is lower than the reflectivity of the second region. The backlight module of claim 11, wherein the light box comprises a box body, the box body has a bottom wall and a plurality of side walls, and the patterned reflective structure is located at the bottom wall of the box body and the At least one of the side walls defines the first zone, the second zone and the third zone. The backlight module of claim 12, wherein the patterned reflective structure is a plurality of patterned reflective sheets. The backlight module of claim 13, wherein each of the patterned reflective sheets has a different reflectivity. The backlight module of claim 13, wherein the portions of the patterned reflective sheet overlap each other, and the exposed patterned reflective sheet and a partial region of the light box define the first region, The second zone and the third zone. The backlight module of claim 13, further comprising an adhesive layer disposed between the patterned reflective sheet and the case. The backlight module of claim 16, wherein the adhesive layer comprises a double-sided adhesive, a heat-curable adhesive or a photo-curable adhesive. The backlight module of claim 12, wherein the patterned reflective structure is a plurality of patterned reflective films to define the first region, the second region, and the third region having different reflectivities. The backlight module of claim 18, wherein each of the patterned reflective films has a different reflectivity. The backlight module of claim 11, further comprising an optical film set disposed on the light box. The backlight module of claim 20, wherein the optical film set comprises a diffusion sheet, a brightness enhancement sheet or a combination thereof. A liquid crystal display device comprising: a backlight module, comprising: a light box having a patterned reflective structure to define a first region, a second region, and a third region having different reflectivities, wherein the The third zone is located between the first zone and the second zone; and at least one lamp tube is disposed in the light box, the lamp tube has a high voltage electrode end and a low voltage electrode end, and the second zone corresponds to a high a piezoelectric pole is disposed, and the first region is disposed at a low voltage electrode end, and a reflectance of the first region is higher than a reflectance of the second region, and a reflectance of the third region is lower than the second region The reflectivity of the area; and a liquid crystal display panel disposed above the backlight module. The liquid crystal display device of claim 22, wherein the light box comprises a box body having a bottom wall and a plurality of side walls, and the patterned reflective structure is located at the bottom and at least one of the side walls One to define the first zone and the second zone. The liquid crystal display device of claim 22, wherein the patterned reflective structure is a plurality of patterned reflective sheets. A liquid crystal display device according to claim 24, wherein Each of the patterned reflective sheets has a different reflectivity. The liquid crystal display device of claim 24, wherein a partial region of each of the reflective sheets overlaps, and the exposed patterned reflective sheet and a partial region of the light box define the first region, The second zone and the third zone. The liquid crystal display device of claim 24, wherein the backlight module further comprises an adhesive layer disposed between the patterned reflective sheet and the housing. The liquid crystal display device of claim 27, wherein the adhesive layer comprises a double-sided tape, a heat-curable adhesive or a photo-curable adhesive. The liquid crystal display device of claim 22, wherein the patterned reflective structure is at least one patterned reflective film to define the first region, the second region, and the third region having different reflectivities. The liquid crystal display device of claim 29, wherein each of the patterned reflective films has a different reflectance. The liquid crystal display device of claim 22, further comprising an optical film set disposed on the light box. The liquid crystal display device of claim 31, wherein the optical film set comprises a diffusion sheet, a brightness enhancement sheet or a combination thereof.