KR101341778B1 - Back light unit and liquid crystal display device using the same - Google Patents

Abstract

The present invention relates to a backlight unit capable of improving display quality of an image by minimizing light interference and increasing luminance, and to a liquid crystal display device using the same, comprising: a plurality of lamp groups including a plurality of lamps; A bottom case accommodating the plurality of lamp groups; A reflection sheet formed on an inner surface of the bottom case to reflect light from the plurality of lamps; A diffusion plate covering a front surface of the bottom case to face the plurality of lamps; A plurality of optical sheets disposed on the front surface of the diffusion plate to uniformize the brightness distribution of the light; And a plurality of partitions between each of the plurality of lamp groups.

Backlight, scanning method, reflective sheet, bulkhead, reflective member,

Description

BACK LIGHT UNIT AND LIQUID CRYSTAL DISPLAY DEVICE USING THE SAME}

1 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a first embodiment of the present invention.

FIG. 2 is a cross-sectional view illustrating another configuration of the liquid crystal display device including the backlight unit illustrated in FIG. 1.

3 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a second embodiment of the present invention.

4 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a third embodiment of the present invention.

5 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a fourth embodiment of the present invention.

6 is a cross-sectional view illustrating another configuration of the liquid crystal display including the backlight unit illustrated in FIG. 5.

* Brief description of symbols for the main parts of the drawings.

PA1, PA2: Bulkhead PAL: Reflector

4: bottom case 6: reflective sheet

8 diffuser 10 optical sheet

12 liquid crystal panel 14 panel guide

1G to 4G: first to second lamp group

The present invention relates to a backlight unit capable of improving display quality of an image by minimizing light interference and increasing luminance, and a liquid crystal display using the same.

As the information society develops, the demand for image display devices for displaying images is increasing in various forms. Recently, liquid crystal display (LCD), plasma display panel (PDP), electro luminescent display (ELD), and VFD ( Various flat panel displays such as Vacuum Fluorescent Display have been utilized.

Among such flat panel displays, liquid crystal displays are widely used due to their low power drive and excellent image quality. As the liquid crystal display, a liquid crystal panel including two substrates facing each other and liquid crystal interposed between the two substrates is used.

The liquid crystal panel displays an image by changing an arrangement of liquid crystals by an electric field generated between two substrates. However, since the liquid crystal panel corresponds to a non-emission display panel, light is supplied from a backlight unit to display an image.

The light source of the backlight unit may include an external electrode fluorescent lamp (EEFL), a light emitting diode (LED), a cold cathode fluorescent lamp (CCFL), and a hot cathode fluorescent lamp (HCFL). ) Is mainly used.

The backlight unit is divided into an edge method and a direct method according to the arrangement of the lamps. In the edge method, the lamp is positioned at the lower side of the liquid crystal panel to supply light by the light guide plate. Located at the bottom to supply light directly to the liquid crystal panel.

Currently, liquid crystal displays have tended to have large areas such as monitors, electronic displays, televisions, and the like. In order to be used, liquid crystal displays must have high luminance. Therefore, a direct method of supplying a high luminance of light by providing a plurality of lamps under the liquid crystal panel is mainly used.

Liquid crystal display devices used for monitors, TVs, and the like display moving images. Blurring occurs due to the slow response speed of liquid crystals, which causes blurring of the image and blurring.

Accordingly, in order to improve blurring in the image, a scanning method of sequentially driving a plurality of lamps in response to the response speed of the liquid crystal is used.

However, in the scanning method, a plurality of lamps are set to a plurality of lamp groups to drive each lamp group sequentially. However, optical interference occurs between the lamp groups, thereby reducing a scanning effect. In other words, the backlight unit of which the scanning effect is reduced due to the optical interference has a problem of reducing the display quality of the image as well as reducing the brightness of the displayed image.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object thereof is to provide a backlight unit capable of improving display quality of an image by minimizing optical interference and increasing luminance, and a liquid crystal display using the same.

A backlight unit according to an embodiment of the present invention for achieving the above object comprises a plurality of lamp group consisting of a plurality of lamps; A bottom case accommodating the plurality of lamp groups; A reflection sheet formed on an inner surface of the bottom case to reflect light from the plurality of lamps; A diffusion plate covering a front surface of the bottom case to face the plurality of lamps; A plurality of optical sheets disposed on the front surface of the diffusion plate to uniformize the brightness distribution of the light; And a plurality of partitions between each of the plurality of lamp groups.

The plurality of barrier ribs may be formed in parallel with the lamp to be in line contact with the diffusion plate, and the plurality of barrier ribs may be higher than the respective lamps and spaced apart from the diffusion plate.

The plurality of barrier ribs may be integrally formed with the reflective sheet and have a cross section formed in one of triangular, square, and round shapes, and the plurality of partition walls may be formed in the bottom case, so that the cross sections are triangular, square, and Characterized in that formed in the shape of any one of the circles. And the outer surface of the partition wall is characterized in that the same material as the reflective sheet is coated.

The plurality of lamp spacing is characterized in that the spacing between the lamps between each partition wall is narrower than the spacing between lamps adjacent to each other without the partition wall therebetween, the height of each of the partition wall and the adjacent lamps is It is characterized in that it is formed higher than the lamps that are not adjacent to the partition wall.

A plurality of reflecting members are further provided between the lamps to have the same height as the respective lamps, and the plurality of reflecting members are formed in a triangular shape so that the plurality of reflecting members have a width smaller than a distance between the lamps. It is characterized by.

The plurality of reflective members may be integrally formed with the reflective sheet, and the plurality of reflective members may be formed on the bottom case, and the same material as the reflective sheet may be coated on the outer surface thereof.

In addition, the liquid crystal display according to the embodiment of the present invention for achieving the above object is characterized in that using a backlight unit having the features as described above.

Hereinafter, a backlight unit and a liquid crystal display using the same according to an embodiment of the present invention having the above characteristics will be described in detail with reference to the accompanying drawings.

1 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a first embodiment of the present invention. 2 is a cross-sectional view illustrating another configuration of the liquid crystal display including the backlight unit illustrated in FIG. 1.

1 and 2 includes a plurality of lamp groups 1G, G2, 3G, and 4G, and a plurality of lamp groups 1G, G2, 3G, and 4G. Bottom case (4) and a plurality of lamp partitions (Partition, PA1) for blocking each of the lamp group (1G, G2, 3G, 4G) is stored and formed on the inner surface of the bottom case (4) A reflecting sheet 6 reflecting light from the lamp 2 of the light source, a diffuser plate 8 covering the front surface of the bottom case 4 so as to face the plurality of lamps 2, and a front surface of the diffuser plate 8. And a liquid crystal panel 12 disposed on the front surface of the optical sheet 10 to uniformize the brightness distribution of the light and adjusting the transmittance of light passing through the optical sheet 10 to display an image.

In addition, the liquid crystal display according to the present invention is disposed in the bottom case 4, the panel guide 14 supporting the liquid crystal panel 12 and the case surrounding the edge of the liquid crystal panel 12 and the side of the bottom case 4 The tower 16 is provided.

The plurality of lamps 2 includes a glass tube coated with a fluorescent material on an inner wall, and electrodes (not shown) formed at both ends of the glass tube. In this case, each of the plurality of lamps 10 may be an external electrode fluorescent lamp, a light emitting diode, a cold cathode tube and a hot cathode fluorescent lamp. Each of the plurality of lamps 10 is turned on by the power applied from the outside to emit light.

The plurality of lamps 2 are set to a plurality of lamp groups 1G, 2G, 3G and 4G to perform sequential driving of the scanning method. In FIG. 1, only four lamp groups 1G, 2G, 3G, and 4G are shown, and four lamp groups 1G, 2G, 3G, and 4G are provided with four lamps. However, the number of lamp groups 1G, 2G, 3G, and 4G and the number of lamps 2 provided in each of the lamp groups 1G, 2G, 3G, and 4G can be easily changed depending on the usage and size of the liquid crystal display. It can be changed. The interval t0 between the lamps 2 can be easily changed according to the number of lamps 2 used.

The bottom case 4 accommodates the plurality of lamps 2, the diffusion plate 8, and the optical sheet 10, and also emits heat generated from the plurality of lamps 2 to the outside.

The reflective sheet 6 is disposed on the front surface of the bottom case 4 to reflect the light leaked from the plurality of lamps 2 toward the diffuser plate 8 to improve light utilization efficiency. In other words, the reflective sheet 6 reflects the light applied from the plurality of lamps 2 in the direction of the bottom case 4 in the direction of the diffuser plate 8 to improve the light efficiency. The reflective sheet 6 is provided with a plurality of partitions PA1 for preventing optical interference between the lamp groups 1G, 2G, 3G, and 4G.

In addition, the reflective sheet 6 may be formed by coating a reflective material, that is, a reflective material on the inner surface of the bottom case 4 as shown in FIG. 2. In this case, the plurality of partitions PA1 may be formed in the bottom case 4, and the reflective sheet 6 may be formed by applying the reflective material to the bottom case 4 and the front surfaces of the partitions PA1.

The plurality of partitions PA1 are disposed between the lamp groups 1G, 2G, 3G, and 4G to contact the diffuser plate 8 to completely block light between the lamp groups 1G, 2G, 3G, and 4G. (P) Each partition wall PA1 shown in FIG. 1 protrudes the reflection sheet 6 vertically in a triangular shape to completely block each lamp group 1G, 2G, 3G, and 4G. To this end, each partition PA1 is preferably formed in parallel with the long axis of the adjacent lamp 2, for example, to have a long axis corresponding to the long axis of the adjacent lamp 8. Each of the barrier ribs PA1 may protrude from the reflective sheet 6 in a square or circular shape, but line contact is preferably performed to minimize the contact surface with the diffusion plate 8. In other words, in order to increase the light reflection efficiency in the diffuser plate 8 direction, it is preferable that the cross section protrudes in a triangular shape. In addition, although not shown, each partition PA1 may be separately formed of a reflective material such as the reflective sheet 6, and may be differently disposed according to each lamp group 1G, 2G, 3G, and 4G. In this case, fixing means for fixing each partition PA1 is further needed.

As shown in FIG. 2, when the reflective sheet 6 is formed by applying a reflective material on the inner surface of the bottom case 4, a plurality of partitions PA1 are formed on the bottom case 4 and the reflective material is formed on the bottom case ( 4) and is applied to the front of each partition (PA1). In other words, each partition wall PA1 is disposed between the lamp groups G1, G2, G3, and G4 of the inner surface of the bottom case 4, and a reflective material may be applied to the surface of each partition wall PA1.

The optical sheet 10 collects light and irradiates the liquid crystal panel 12 so that the light diffused by the diffusion plate 8 uniformly proceeds in the direction perpendicular to the liquid crystal panel 12. Here, the optical sheet 10 is largely composed of a diffusion sheet, a prism sheet, a protective sheet and the like. The diffusion sheet uniformly diffuses the light from the lamp 2, the prism sheet is located in front of the diffusion sheet to collect and diffuse the light diffused in the diffusion sheet to the liquid crystal panel 12, the protective sheet of the prism sheet It also protects multiple optical sheets from the front.

The panel guide 14 is disposed in the bottom case 4 to press the optical sheet 10 and the diffusion plate 8 to prevent the flow of the optical sheet 10 and the diffusion plate 8. In this case, a pressure pad (not shown) may be disposed between the panel guide 14 and the diffusion plate 8. Here, the pressure pad may be formed of silicon or rubber to prevent light leakage by removing the gap between the panel guide 10 and the diffusion plate 8.

The panel guide 14 supports the rear edge of the liquid crystal panel 12. To this end, the panel guide 14 is provided with a panel seating portion formed to correspond to the rear edge of the liquid crystal panel 12.

The liquid crystal panel 12 may include a transistor array substrate 12b and a color filter array substrate 12a bonded together to face each other, a spacer (not shown) for maintaining a constant cell gap between the two array substrates 12a and 12b; A liquid crystal layer (not shown) is provided in the liquid crystal space provided by the spacer.

The color filter array substrate 12a includes a color filter, a common electrode, a black matrix, and the like. Here, the common electrode may be formed on the transistor array substrate 12b.

The transistor array substrate 12b is a thin film transistor (not shown) formed in a region defined by a plurality of data lines (not shown) and a plurality of gate lines (not shown) and connected to the gate line and the data line, and the thin film transistor. A liquid crystal cell (not shown) connected to the is provided.

In addition, a lower polarizing film (not shown) facing the optical sheet 10 is attached to the rear surface of the transistor array substrate 12b. The lower polarizing film polarizes the light irradiated from the optical sheet 10. At this time, the transmission axis of the lower polarizing film is disposed at a predetermined angle to match the alignment direction of the liquid crystal layer.

An upper polarizing film (not shown) is attached to the rear surface of the color filter array substrate 12a. The upper polarizing film polarizes light passing through the liquid crystal layer and the color filter array substrate 12a. At this time, the transmission axis of the upper polarizing film is disposed to be perpendicular to the transmission axis of the lower polarizing film.

The liquid crystal panel 12 is disposed in the panel seating portion of the panel guide 14 disposed in the bottom case 4. In this case, a buffer pad (not shown) may be disposed between the panel seating portion of the panel guide 14 and the lower polarizing film. The buffer pad may be formed of silicon or rubber to prevent a light leakage by removing a gap between the panel guide 14 and the liquid crystal panel 12 and to cushion the shock applied to the liquid crystal panel 12.

The case top 16 surrounds the front edge of the liquid crystal panel 12 disposed on the panel guide 14 and the side surfaces of the bottom cover 20 and the panel guide 14.

The backlight unit and the liquid crystal display using the same according to the first exemplary embodiment of the present invention configured as described above drive each lamp 2 or each lamp group 1G, 2G, 3G, and 4G while scanning each lamp. A defect due to optical interference between the groups 1G, 2G, 3G, and 4G can be prevented. In other words, the reflective sheet 6 of the backlight unit is provided with a plurality of partition walls PA1 for blocking the lamp groups 1G, 2G, 3G, and 4G, and thus, each lamp group 1G, 2G, 3G, and 4G. It blocks the optical interference generated in between. Accordingly, the image display quality can be increased by uniformly applying light to the liquid crystal display including the liquid crystal panel 12.

However, the liquid crystal display using the backlight unit according to the first embodiment of the present invention may cause a problem in which dark lines are formed on the display screen of the image. In other words, light is not transmitted to a contact portion of each partition PA1 and the diffusion plate 8 provided in the reflective sheet 6, for example, a portion corresponding to the vertex P of each partition PA1. do. Accordingly, a dark line may occur in response to a portion of the liquid crystal panel 12 corresponding to the vertex P of each partition PA1, that is, a line contact portion of each partition PA1.

In order to solve the above problems, the backlight unit according to the second exemplary embodiment of the present invention prevents dark lines of the liquid crystal display while minimizing optical interference between the lamp groups G1, G2, G3, and G4. (PA1) Change the structure.

3 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a second exemplary embodiment of the present invention.

3 includes a plurality of lamp groups 1G, G2, 3G, and 4G, and a plurality of lamp groups 1G, G2, 3G, and 4G, each of which includes a plurality of lamps 2. The bottom case 4 and the plurality of lamps 1G, G2, 3G, and 4G are provided with a plurality of partitions PA2 for blocking a part of the bottom case 4 and are formed in front of the plurality of lamps 2. A reflection sheet 6 for reflecting light from the light source, a diffuser plate 8 covering the front surface of the bottom case 4 so as to face the plurality of lamps 2, and a front surface of the diffuser plate 8 so as to adjust the brightness distribution of the light. The optical sheet 10 to be uniform and the liquid crystal panel 12 disposed on the front surface of the optical sheet 10 to adjust the transmittance of light passing through the optical sheet 10 to display an image.

The liquid crystal display including the backlight unit according to the second exemplary embodiment of the present invention has the same configuration as the first exemplary embodiment of the present invention shown in FIGS. 1 and 2 except for the structure of the partition wall PA2. . Accordingly, the same components are denoted by the same reference numerals as those shown in FIGS. 1 and 2, and detailed description thereof will be replaced with the first embodiment.

The plurality of partitions PA2 according to the second embodiment of the present invention are integrally formed with the reflective sheet 6 and positioned between the lamp groups 1G, 2G, 3G, and 4G. At this time, each partition PA2 has a height that does not contact the diffuser plate 8 so as to block only part of the light between the lamp groups 1G, 2G, 3G, and 4G.

Specifically, each of the partitions PA2 protrudes vertically from the reflective sheet 6 in a triangular shape, wherein the height of the vertex P of each of the partitions PA2 is higher than that of the plurality of lamps 2. Formed to the position. That is, as shown in FIG. 3, the position of the uppermost vertex P of each partition PA2 is higher than that of each lamp 2 and is spaced apart from the diffuser plate 8. Accordingly, the uppermost vertex P of each partition PA2 has a height t3 between each lamp 2 and the diffusion plate 8.

In FIG. 3, the uppermost vertex P of each partition PA2 is 1.5 times the height t4 of the height t1 of the lamp 2, that is, the 3/4 position between the reflecting sheet 6 and the diffuser plate 8. It was formed at. Accordingly, each partition wall PA2 blocks 3/4 of each lamp group 1G, 2G, 3G, and 4G. Further, each partition PA2 is preferably formed in parallel with each lamp 8 in parallel with the long axis of the adjacent lamp 2, that is, to have a long axis corresponding to the long axis of the lamp 8. The plurality of partitions PA2 may protrude in a square or circular shape integrally with the reflective sheet 6, but have one vertex P in order to increase the light reflection efficiency toward the diffuser plate 8. It is preferable that the cross section protrudes in triangular shape. In addition, although not shown, each of the partitions PA2 may be separately formed of a reflective material such as the reflective sheet 6, and may be disposed differently according to each lamp group 1G, 2G, 3G, and 4G. In this case, fixing means for fixing each partition wall PA2 is further required.

In addition, the reflective sheet 6 may be formed by coating a reflective material on the inner surface of the bottom case 4. In this case, a plurality of partitions PA2 are formed on the bottom case 4, and the reflective sheet 6 may be formed by applying a reflective material to the bottom case 4 and the front surfaces of the partitions PA2.

The backlight unit and the liquid crystal display using the same according to the second exemplary embodiment of the present invention configured as described above drive each lamp 2 or each lamp group 1G, 2G, 3G, and 4G while scanning each lamp. It is possible to prevent defects due to optical interference between the groups 1G, 2G, 3G, and 4G, and to prevent dark lines in the liquid crystal panel 2. In other words, the reflective sheet 6 of the backlight unit is provided with a plurality of partitions PA2 for blocking 3/4 of the lamp groups 1G, 2G, 3G, and 4G, so that each lamp group 1G, 2G, It blocks 3/4 of the optical interference generated between 3G and 4G). Also. The vertex P of each partition PA2 is formed so as not to contact the diffuser plate 8. As a result, light is uniformly applied to the liquid crystal display including the liquid crystal panel 12, and darkening of the liquid crystal panel 12 may be prevented to increase image display quality.

4 is a cross-sectional view illustrating a liquid crystal display device including the backlight unit according to the third embodiment of the present invention.

The liquid crystal display including the backlight unit illustrated in FIG. 4 includes a plurality of lamps 2a and 2b configured to have different positions, a bottom case 4 which accommodates a plurality of lamps 2a and 2b, and a plurality of lamps 2a. And a partition wall PA1 for blocking each of the plurality of lamp groups 1G, G2, 3G, and 4G, each of which is composed of 2b) and disposed at the front of the bottom case 4 to provide light from the plurality of lamps 2a and 2b. A reflecting sheet 6 reflecting the light, a diffuser plate 8 covering the front surface of the bottom case 4 so as to face the plurality of lamps 2a and 2b, and a front surface of the diffuser plate 8 so as to uniformly distribute the brightness of light. The optical sheet 10 and the liquid crystal panel 12 disposed on the front surface of the optical sheet 10 to adjust the transmittance of light passing through the optical sheet 10 to display an image.

In the liquid crystal display including the backlight unit according to the third exemplary embodiment of the present invention, the first configuration of the present invention is illustrated in FIGS. 1 and 2 except for the structure of the plurality of lamps 2a and 2b configured to have different positions. Same as the embodiment configuration. Accordingly, the same components are denoted by the same reference numerals as those shown in FIGS. 1 and 2, and detailed description thereof will be replaced with the first embodiment.

The plurality of lamps 2a and 2b are set to a plurality of lamp groups 1G, 2G, 3G, and 4G to perform sequential driving of the scanning method. Further, the interval t0, t0 'between each lamp 2a, 2b, the interval t1, t4 between the reflective sheet 6 and each lamp 2a, 2b, each partition PA1 and each lamp 2a, The interval t5 between 2b) is changed to further improve the light efficiency in the state where the plurality of partitions PA1 are formed.

Specifically, the spacing between the lamps 2a with each partition PA1 interposed therebetween is smaller than the spacing between lamps 2b without each partition PA1 interposed therebetween. In other words, the spacing between each partition PA1 and adjacent lamps 2a is formed at a narrower spacing than the spacing between each partition PA1 and non-adjacent lamps 2b. In addition, the interval t0 between the partition walls PA1 and the non-adjacent lamps 2b may also be formed at a wider interval than in the case of the first and second embodiments. Accordingly, the interval t5 between the ramps 2a adjacent to each of the partitions PA1 and each of the partitions PA1 may be formed at a narrower interval than in the first and second embodiments. The liquid crystal display including the backlight unit illustrated in FIG. 4 includes a plurality of lamps 2a and 2b configured to have different positions, a bottom case 4 which accommodates a plurality of lamps 2a and 2b, and a plurality of lamps 2a. And a partition wall PA1 for blocking each of the plurality of lamp groups 1G, G2, 3G, and 4G, each of which is composed of 2b) and disposed at the front of the bottom case 4 to provide light from the plurality of lamps 2a and 2b. A reflecting sheet 6 reflecting the light, a diffuser plate 8 covering the front surface of the bottom case 4 so as to face the plurality of lamps 2a and 2b, and a front surface of the diffuser plate 8 so as to uniformly distribute the brightness of light. The optical sheet 10 and the liquid crystal panel 12 disposed on the front surface of the optical sheet 10 to adjust the transmittance of light passing through the optical sheet 10 to display an image.

In the liquid crystal display including the backlight unit according to the third exemplary embodiment of the present invention, the first configuration of the present invention is illustrated in FIGS. 1 and 2 except for the structure of the plurality of lamps 2a and 2b configured to have different positions. Same as the embodiment configuration. Accordingly, the same components are denoted by the same reference numerals as those shown in FIGS. 1 and 2, and detailed description thereof will be replaced with the first embodiment.

The plurality of lamps 2a and 2b are set to a plurality of lamp groups 1G, 2G, 3G, and 4G to perform sequential driving of the scanning method. Further, the interval t0, t0 'between each lamp 2a, 2b, the interval t1, t4 between the reflective sheet 6 and each lamp 2a, 2b, each partition PA1 and each lamp 2a, The interval t5 between 2b) is changed to further improve the light efficiency in the state where the plurality of partitions PA1 are formed.

Specifically, the spacing between the lamps 2a with each partition PA1 interposed therebetween is smaller than the spacing between lamps 2b without each partition PA1 interposed therebetween. In other words, the gap between each partition PA1 and the adjacent lamps 2a is formed at a narrower interval than the gap between each partition PA1 and the non-adjacent lamps 2b. In addition, the interval t0 between the partition walls PA1 and the non-adjacent lamps 2b may also be formed at a wider interval than in the first and second embodiments. Accordingly, the interval t5 between the ramps 2a adjacent to each of the partitions PA1 and each of the partitions PA1 may be formed at a narrower interval than in the first and second embodiments.

In addition, the distance t4 between the reflective sheets 6 of the lamps 2a at positions adjacent to each of the partitions PA1, that is, the height t4 of the lamps 2a adjacent to each of the partitions PA1 is determined by each partition PA1. It may be formed higher than the height (t1) of the lamp (2b) that is not adjacent to the.

4 shows only four lamp groups 1G, 2G, 3G, and 4G, and each of the four lamp groups 1G, 2G, 3G, and 4G is provided with four lamps 2. However, the number of lamp groups 1G, 2G, 3G, and 4G and the number of lamps 2a and 2b included in each of the lamp groups 1G, 2G, 3G, and 4G may vary depending on the usage and size of the liquid crystal display. It can be changed easily. In addition, although the plurality of partitions PA1 shown in FIG. 4 represent a plurality of partitions PA1 according to the first embodiment, a plurality of partitions PA2 shown in the second embodiment and FIG. 3 may be used. .

In the backlight unit and the liquid crystal display using the same according to the third embodiment of the present invention configured as described above, each of the partitions PA1 and PA1 is provided in the state where the plurality of partitions PA1 and PA2 according to the first and second embodiments are provided. It is configured by changing the positions of the plurality of lamps 2a adjacent to PA2). That is, the spacing between the lamps 2a with the partitions PA1 and PA2 between them becomes narrower, and the spacing between the lamps 2a and the diffuser plate 8 can be further narrowed. In this case, since the luminance is proportional to the square of the distance, the lamps 2b positioned adjacent to each of the partitions PA1 may be densely positioned to improve the luminance of the adjacent area of each of the partitions PA1. Accordingly, in the state where the plurality of partitions PA1 and PA2 are formed, it is possible to further improve the light efficiency while preventing the optical interference.

5 is a cross-sectional view illustrating a liquid crystal display including a backlight unit according to a fourth embodiment of the present invention. 6 is a cross-sectional view illustrating another configuration of the liquid crystal display including the backlight unit illustrated in FIG. 5.

5 and 6 includes a plurality of lamps 2, a bottom case 4 containing a plurality of lamps 2, and a plurality of lamp groups 1G, G2, 3G, and 4G. Reflective sheet 6 and a plurality of lamps having a plurality of reflecting members PAL between the partition walls PA1 for blocking each one and each lamp 2 to reflect light from the plurality of lamps 2). 2) the diffusion plate 8 covering the front surface of the bottom case 4 and the optical sheet 10 and the optical sheet 10 disposed on the front surface of the diffusion plate 8 to uniform the light distribution. The liquid crystal panel 12 is disposed on the front surface to adjust the transmittance of light passing through the optical sheet 10 to display an image.

In the liquid crystal display including the backlight unit according to the fourth exemplary embodiment of the present invention, the structure of the partition wall PA1 and the rest of the configuration except for each reflective member PAL are shown in FIGS. 1 to 4. The configuration is the same as in the third embodiment. Accordingly, the same components will be denoted by the same reference numerals as those shown in FIGS. 1 to 4, and detailed description thereof will be replaced with the first to third embodiments.

The plurality of partitions PA1 according to the fourth exemplary embodiment of the present invention are integrally formed with the reflective sheet 6 and disposed between the lamp groups 1G, 2G, 3G, and 4G. At this time, each partition wall PA1 has a height in contact with the diffusion plate 8 so as to completely block the light between each lamp group (1G, 2G, 3G, 4G). Here, the height of each partition wall PA1 may have a height that does not contact the diffuser plate 8 so as to block only a part of the lamp groups 1G, 2G, 3G, and 4G as shown in FIG. 3.

In addition, a plurality of reflecting members PAL are provided between the partitions PA1 to correspond to the interval t0 between the lamps 2. In other words, the plurality of reflecting members PAL protrude vertically so that the cross section thereof has a triangular shape integrally with the reflecting sheet 6, wherein each reflecting member PAL is disposed between the lamps 2. It is preferable. The triangular reflective member PAL has the same height t1 or lower than each lamp 2 as each lamp 2, and has a width smaller than the interval to of each lamp 2. In this case, since the luminance is proportional to the square of the distance, the luminance of the liquid crystal panel 12 may be improved by increasing the light efficiency of the lamps 2 adjacent to each of the reflective members PAL. In addition, it is preferable that each reflecting member PAL is formed in parallel with an adjacent lamp 2, that is, to have a long axis corresponding to the long axis of each lamp 8. Each of the reflective members PAL may protrude from the reflective sheet 6 in a square or circular shape. However, the reflective members PAL may protrude in a triangular shape in order to increase the light reflection efficiency toward the diffuser plate 8.

In addition, although not shown, each reflective member PAL may be separately formed of a reflective material such as the reflective sheet 6, and may be arranged differently according to the number of the lamps 2. In this case, fixing means for fixing each reflecting member PAL is further required.

Meanwhile, as shown in FIG. 6, the reflective sheet 6 according to the fourth embodiment may be formed by coating a reflective material on the inner surface of the bottom case 4. In this case, a plurality of partitions PA2 and a plurality of reflecting members PAL are formed on the bottom case 4, and a reflective material is formed on the inner surface of the bottom case 4, each partition PA2, and each reflecting member PAL. The reflective sheet 6 may be formed by being applied to the entire surface of the substrate.

As described above, the liquid crystal display including the backlight unit according to the exemplary embodiment of the present invention increases the luminance of the liquid crystal panel 12 and prevents optical interference between the lamp groups 1G, 2G, 3G, and 4G. prevent. In addition, the display quality of the image may be increased by uniformly applying light by preventing dark lines generated by the partition walls PA1 and PA2.

The present invention described above is not limited to the above-described embodiment and the accompanying drawings, and it is common in the art that various substitutions, modifications, and changes can be made without departing from the technical spirit of the present invention. It will be evident to those who have knowledge of.

As described above, the backlight unit and the liquid crystal display using the same increase the luminance of the liquid crystal panel and prevent optical interference between lamp groups. In addition, the display quality of the image may be increased by uniformly applying light by preventing dark lines generated by a plurality of partition walls.

Claims (13)

A plurality of lamp groups consisting of a plurality of lamps; A bottom case accommodating the plurality of lamp groups; A reflection sheet formed on an inner surface of the bottom case to reflect light from the plurality of lamps; A diffusion plate formed to cover an entire surface of the bottom case to diffuse light from each of the lamps; A plurality of optical sheets disposed on the front surface of the diffusion plate to uniformize the brightness distribution of the light; And A plurality of partitions are provided between each of the plurality of lamp groups, The plurality of lamp intervals The spacing between the lamps having the respective partitions therebetween is formed to be narrower than the gap between the lamps adjacent to each other without having the partitions therebetween, The height of the lamps adjacent to each of the partition walls Backlights are formed higher than the lamps adjacent to each other without interposing the partition walls, but adjacent lamps adjacent to each other without the partition walls are formed closer to the bottom case than the lamps adjacent to the partition walls. unit. The method of claim 1, The plurality of partitions The backlight unit is formed in parallel with the lamp is in line contact with the diffusion plate. The method of claim 2, The plurality of partitions A backlight unit, which is higher than each of the lamps and spaced apart from the diffusion plate. The method of claim 3, wherein The plurality of partitions And a cross section integrally with the reflective sheet in a shape of any one of a triangular, square, and circular shape. The method of claim 3, wherein The plurality of partitions The backlight unit is formed in the bottom case, characterized in that the cross section is formed in any one of the shape of triangular, square and circular. 6. The method of claim 5, On the outer surface of the plurality of partitions And the same material as the reflective sheet is coated. delete delete The method of claim 6, Between each lamp And a plurality of reflective members are further provided to have the same height as the respective lamps. The method of claim 9, The plurality of reflective members And a cross section formed in a triangular shape so as to have a width smaller than a distance between the lamps. 11. The method of claim 10, The plurality of reflective members The backlight unit, characterized in that formed integrally with the reflective sheet. The method of claim 11, The plurality of reflective members The backlight unit is formed on the bottom case and the same material as the reflective sheet is coated on the outer surface. A backlight unit according to any one of claims 1 to 6 and 9 to 12 is used.

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