KR20170109164A - Backlighe unit and display device comprising the same - Google Patents

Abstract

The present invention relates to a backlight unit and a display device including the same. More specifically, the backlight unit according to the present invention can improve the coverage and reflectivity of light emitted from a light source by arranging the light source in a position protruding from the bottom of a reflective plate which is inclined toward the lower side from the outside to the inside, with a preset height. Moreover, if the backlight unit according to the present invention is used, the uniformity of brightness can be secured even if a relatively small number of light sources are used. Accordingly, a lightweight and thin display device can be implemented with low costs.

Description

BACKLIGHT UNIT AND DISPLAY DEVICE COMPRISING THE SAME [0002]

The present invention relates to a backlight unit capable of improving the reflectance and coverage of light emitted from a light source by disposing a light source at a position protruding from a bottom of an inclined reflector by a predetermined height, and a display device including the backlight unit.

2. Description of the Related Art Recent developments in information technology and mobile communication technology have led to the development of display devices capable of visually displaying information. A display device is largely classified into a self-luminous display device having a light emission characteristic and a non-light emitting display device capable of displaying an image due to an external factor.

A typical example of the non-light emitting type display device is a liquid crystal display (LCD) device.

Since the LCD device is an element that does not have a self-luminous element, a separate light source is required. Accordingly, a backlight unit having a light source on the back surface is provided, and light is irradiated toward the front surface of the LCD, thereby realizing an image which can be identified only through the backlight unit.

The backlight unit uses a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp, or a light emitting diode (LED) as a light source.

Particularly, the light emitting element has characteristics such as small size, low power consumption, high reliability, and is widely used as a display light source.

On the other hand, general backlight units are classified into an edge type and a direct type according to the arrangement of light sources. In the edge type system, the light source unit including one light source or a plurality of light sources has a structure in which the light source unit is disposed on one side of the diffuser plate, or both light sources are arranged on each side of the diffuser plate, And a structure disposed below the optical sheet.

In this case, since the light source is disposed at the lower part of the optical sheet, the direct type is used mainly in a display device in which lightness and thinness are relatively smaller than those of an edge type, and brightness rather than thickness and weight are important.

In the edge type method, it is difficult to supply light of a uniform luminance to a large-sized display panel as compared with a direct-type type, and is mainly used for a display device in which a screen is relatively small, light weight and thinness are important.

In recent years, consumption of a large-screen display device has been increasing due to consumer demands. As a result, there is an increasing demand for lightness and thinness as well as high resolution and high brightness for large screen display devices.

FIG. 1 is an exploded perspective view of a direct-type display device using a general light-emitting device as a light source, and FIG. 2 is a cross-sectional view of a display device cut along a perforated line A-A 'of FIG. 3 schematically shows an emission angle at which light is emitted from the light source of Fig.

Referring to FIGS. 1 and 2, a typical display device includes a display panel 10 and a backlight unit 20 disposed on a rear surface thereof.

Here, the backlight unit 20 includes a reflection plate 22 and a light source 23 disposed along a plurality of rows and columns. A diffusion plate 24 is provided at an upper portion of the light source 23 by a predetermined distance h and an optical sheet 25 is disposed at an upper portion of the diffusion plate 24.

The light emitted from the adjacent light sources 23 is superimposed and mixed with each other in the space separated from the diffusion plate 24 and is incident on the diffusion plate 24 in the form of a surface light source. At this time, the light source 23 generally uses a refractive lens to improve the directivity angle of the emitted light.

The display panel 10 and the backlight unit 20 are modularized through the upper cover 40, the guide panel 30 and the lower cover 21.

Optical design for increasing the number of light sources or optical sheets for the realization of high resolution and high brightness of a display device having the above structure is considered.

However, there is a problem that the product price increases as the number of the light sources 23 or the optical sheets 25 is increased.

Particularly, when the number of light sources (for example, light emitting devices) is increased, the number of PCBs for mounting the light emitting devices and the number of lenses for refracting light emitted from the light sources, . Also, as the number of light sources increases, implementation of low power consumption may be difficult, and heat dissipation due to heat generation of the light emitting device may be caused.

The direct type display device requires a predetermined gap h, that is, an optical gap, between the light source 23 and the diffuser plate 24 due to the characteristics of the lens applied to the light source 23 and the light source 23.

At this time, if the optical gap is reduced to reduce the thickness of the display device, there is a possibility that the dark portions B 1 and B 2 are not overlapped and mixed with each other. As described above, the display quality may be degraded due to the luminance unevenness.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a backlight unit capable of realizing uniform brightness without increasing the number of light sources or optical sheets by improving the reflectance and coverage of light emitted from a light source .

Another object of the present invention is to provide a backlight unit capable of ensuring luminance uniformity even when the spacing between the light source and the diffusion plate is reduced by improving the reflectivity and coverage of light emitted from the light source.

Another object of the present invention is to provide a display device which has a uniform luminance and is lightweight and thin.

According to an aspect of the present invention, there is provided an image forming apparatus including an inclined portion inclined downward from an outer side toward an inner side, and at least one protruding portion protruding upward from a bottom portion of the inclined portion at a predetermined height, A backlight unit including a reflection plate may be provided.

Here, the backlight unit can be provided in which the reflectance and coverage of the light emitted from the light source can be improved by disposing the light source at a position higher than the bottom of the inclined reflector.

According to another aspect of the present invention, a backlight unit using a lower cover and a reflection plate having a sloped structure can be made thin, and even if a relatively small number of light sources are disposed, the uniformity of luminance A display device can be realized which can be secured.

The reflectance of the backlight unit according to the present invention may be increased as compared with the light emitted from the light source disposed at the same height as the bottom of the reflector. As a result, an effect of increasing the overlapping and mixing space of light in the backlight unit can be caused.

In addition, since the light source is disposed at a position higher than the bottom of the reflection plate, the coverage area by one light source can be improved, so that even if a relatively small number of light sources are used, light can be uniformly directed toward the diffusion plate.

According to the present invention, even if the space between the light source and the diffusion plate is reduced, a region where the light emitted from the light source is focused is higher than other regions, or a dark portion where light is not superimposed and mixed is generated It is possible to reduce the possibility.

1 is an exploded perspective view of a direct-type display device using a general light-emitting device as a light source.
2 is a cross-sectional view of a display device cut along the perforated line A-A 'in Fig.
3 schematically shows an emission angle at which light is emitted from the light source of Fig.
4 is an exploded perspective view of a display device according to an embodiment of the present invention.
5 is a cross-sectional view of the display device cut along the perforated line A-A 'in Fig.
6 is a cross-sectional view of a display device cut along a perforated line B-B 'in FIG.
7 is a cross-sectional view of a light source unit used in a display device according to an embodiment of the present invention.
8 is an exploded perspective view of a light source unit used in a display device according to an embodiment of the present invention.
9 is an exploded perspective view of a light source unit used in a display device according to another embodiment of the present invention.
10 is a cross-sectional view of a display device according to another embodiment of the present invention.
11 is a cross-sectional view of a display device according to another embodiment of the present invention.
12 to 14 are sectional views of a display device according to various embodiments of the present invention.
15 and 16 are sectional views of an outer portion of a display device according to an embodiment of the present invention.

Hereinafter, a backlight unit and a display device including the backlight unit according to various embodiments of the present invention will be described in detail with reference to the drawings.

4 is an exploded perspective view of a display device according to an embodiment of the present invention. FIG. 5 is a cross-sectional view of a display device cut along a perforated line A-A 'of FIG. 4, and FIG. 6 is a cross-sectional view of a display device cut along a perforated line B-B' of FIG.

Referring to FIG. 4, the display apparatus includes a display panel 110 and a backlight unit 120 disposed on a rear surface thereof.

First, the display panel 110 is a part that plays a key role in image display, and includes an array substrate and a color filter substrate which are bonded to each other with a liquid crystal layer interposed therebetween.

On the inner surface of the array substrate, a plurality of gate lines and a plurality of data lines cross each other to define pixels, and thin film transistors are provided at the intersections of the gate lines and the data lines, and are connected to the pixel electrodes provided in each pixel.

On the inner surface of the color filter substrate, a black matrix is provided to cover the non-display elements (gate lines, data lines, thin film transistors, etc.) of the array substrate together with the color filters corresponding to the respective pixels, .

When the thin film transistor selected for each gate line is turned on by the on / off signal of the gate driving circuit, the display panel 110 transmits the signal voltage of the data driving circuit to the corresponding pixel electrode through the data line. Accordingly, the arrangement direction of the liquid crystal in the liquid crystal layer is changed by the electric field between the pixel electrode and the common electrode, and a difference in transmittance is exhibited.

A backlight unit 120 for supplying light is disposed on the back surface of the display panel 110 so that the difference in transmittance of the display panel 110 can be expressed externally.

The backlight unit 120 includes the light source unit 123 and the reflection plate 122 and the bottom cover 121 is provided on the back surface of the reflection plate 122. The diffusion plate 124 is spaced apart from the light source 123 by a predetermined distance and the optical sheet 125 is disposed on the diffusion plate 124.

Here, the optical sheet 125 may include a diffusion sheet, at least one light-condensing sheet, and the like, and may further include various functional sheets such as a reflective polarizing film such as a dual brightness enhancement film (DBEF).

The light emitted from the light source unit 123 may be directly incident on the diffuser plate 124 or may be reflected by the reflector plate 122 and incident on the diffuser plate 124. The diffuser plate 124 and the optical sheet 125 may be successively And is incident on the display panel 110 so that an image is ultimately displayed on the outside.

FIG. 7 is a cross-sectional view of a light source unit used in a display device according to an embodiment of the present invention, and FIGS. 8 and 9 are exploded perspective views of a light source unit used in a display device according to an embodiment of the present invention.

7 to 9, the light source unit 123 is provided as a bar-shaped light emitting device array including a plurality of light emitting devices 123b.

Specifically, the light source 123 includes a circuit board 123a having a circuit pattern for electrically connecting to the plurality of light emitting devices 123b. The circuit board 123a includes a plurality Emitting elements 123b are arranged with an interval.

According to another modification, the light emitting devices 123b can be arranged in a zigzag manner along the longitudinal direction of the circuit board 123a. It is possible to increase the angle of the light emitted from the light emitting element array toward the width direction of the circuit board 123a even if the same number of the light emitting elements 123b are arranged by arranging the light emitting elements 123b in zigzags, Can be improved.

The diffusion unit 123c is provided to improve the luminance uniformity by changing the outgoing angle of the light emitted from the light emitting element 123b and the reflection lens 123d is provided on the diffusion unit 123c .

The reflection lens 123d can be formed as a plate by combining a synthetic resin plate having a high light reflectance or a material having a high light reflectivity with a synthetic resin.

The reflective lens 123d has an inverted triangular cross section and the reflective surface 125e facing the light emitting device 123b may be formed into a spherical surface, an aspheric surface, or a plane in consideration of required light diffusion characteristics.

The light emitted from the light emitting device 123b toward the reflecting surface 125e of the reflecting lens 123d passes through the reflecting lens 123d and enters the diffuser plate 124 or totally reflects toward the reflecting plate 122 .

For example, L1 in the light outgoing direction shown in Fig. 7 represents light incident on the diffuser plate 124 through the reflection lens 123d, and L2 indicates the light incident on the reflection surface 123e of the reflection lens 123d And is incident on the reflection plate 122 again.

The reflective lens 123d may be provided individually for each light emitting device 123b but may be provided to cover all the upper portions of the plurality of light emitting devices 123b disposed on the circuit substrate 123a forming one row. .

That is, since one reflective lens 123d is provided on one circuit board 123a, the manufacturing cost of the light emitting device array can be reduced. In addition, since there is a high possibility that light leaks through spaces between the reflective lenses 123d individually provided for the respective light emitting devices 123b, the luminance of the display region corresponding to the upper portion of the light emitting device array becomes higher than the other regions, Non-uniformity may be caused. On the other hand, when one reflective lens 123d is provided to cover all of the plurality of light emitting devices 123b disposed on one circuit board 123a, light leakage through the space between the reflective lenses 123d can be reduced have.

The display panel 110 and the backlight unit 120 are modularized through the upper cover 140, the guide panel 130, and the lower cover 121.

Specifically, the display panel 110 is positioned above the guide panel 130, and the backlight unit 120 is positioned below the guide panel 130.

The upper cover 140 is provided to cover an upper surface of the display panel 110 and an upper surface and a side surface of the guide panel 130 that are seated on the upper portion of the guide panel 130. Further, the upper cover 140 and the lower cover 121 are fixed by the guide panel 130.

Hereinafter, the tilting structure of the reflection plate 122 shown in Figs. 5 and 6 will be described in more detail with reference to the reference numerals of the edges of the reflection plate 122 shown in Fig.

4, the rim of the reflection plate 122 in contact with the diffuser plate 124 includes a first rim a and a second rim b facing each other, a first rim a and a second rim b, And a third rim c and a fourth rim d connecting the sides b.

Here, the first rim a and the second rim b are parallel to each other, and the third rim c and the fourth rim d may be parallel to each other.

5 showing a cross-sectional view of a display device cut along a perforated line A-A ', a reflection plate 122 used in a backlight unit 120 according to an embodiment of the present invention has a lower portion So as to have a predetermined inclination toward the center line.

At this time, the reflection plate 122 includes an inclined portion inclined downward from the outside toward the inside.

For example, the reflection plate 122 includes a first inclined portion 122a inclined to have a first inclination [theta] 1 toward the bottom as viewed inward from the first rim a, And a second inclined portion 122b inclined so as to angle the second inclination [theta] 2 toward the lower portion toward the inner side in the second inclined portion 122b. At this time, the first slope? 1 and the second slope? 2 may be set to be the same or different from each other as needed.

The light emitted from the light source 123 is incident on the first inclined portion 122a or the second inclined portion 122b of the reflector 122. The first inclined portion 122a and the second inclined portion 122b are located adjacent to each other, And may be reflected by the second inclined portion 122b and irradiated to the diffuser plate 124. [

6 showing a cross-sectional view of the display device cut along the perforated line B-B ', the reflection plate 122 has a third inclination? 3 toward the lower side toward the inner side from the third edge c. And a fourth inclined portion 122d inclined so that the fourth inclination 4 is inclined downward toward the inside toward the fourth rim portion d from the fourth rim portion d .

At this time, the third slope? 3 and the fourth slope? 4 may be set to be the same or different from each other as needed. Further, the third slope? 3 and the fourth slope? 4 may be set different from the first slope? 1 and the second slope? 2. Since the third inclined portion 122c and the fourth inclined portion 122d are additionally provided along with the first inclined portion 122a and the second inclined portion 122b, the reflectance of light through the inclined surfaces of the reflector 122 can be improved It is possible to increase the overlapping and mixing space of light.

As described above, it is possible to provide the reflection plate 122 having a shape in which the distance from the diffusion plate 124 is narrowed toward the outside as the first to fourth slopes? 1 to? 4 are adjusted. In addition, since the lower cover 121 is inclined to correspond to the lower surface of the reflection plate 122, it is possible to reduce the thickness of the display device.

The lower cover 121 may be provided to be in contact with the lower surface of the protrusion 126 of the reflection plate 122 while the lower cover 121 may be provided to be spaced apart from the reflection plate 122 at the slope of the lower cover 121. [ have. 10 showing a cross-sectional view of a display device cut along a perforated line A-A ', for example, the lower cover 121 is formed from the bottom of the side wall 121a and the side wall 121a, And a lower inclined portion 121b which is inclined toward the lower inclined portion 121b. At this time, a slope (ψ) formed by the side wall 121a of the lower cover 121 and the lower inclined portion 121b may be smaller than 90 °. In addition, it is understood that the backlight unit according to various embodiments of the present invention may include various shapes of the lower cover 121 for supporting the reflector 122 with the inclined portion and the protrusion.

Unlike the conventional backlight unit shown in FIG. 2, the backlight unit according to various embodiments of the present invention described above and the display device including the backlight unit according to various embodiments of the present invention have a structure in which light emitted in a relatively horizontal direction from the light source unit 123 has a tilted structure The light can be totally reflected upward by the reflection plate 122, so that the area that can be covered by one light source 123 can be relatively increased.

In addition, as the light emitted from the light source 123 is totally reflected by the inclined reflecting plate 122, the space in which the light is superimposed and mixed in the backlight unit 120 can be relatively increased.

Accordingly, it is possible to reduce the possibility that a region where the light emitted from the light source 123 is concentrated in a region where the luminance is higher than other regions, or a dark region where light is not superimposed or mixed with each other.

That is, when using the same number of light emitting elements as the conventional backlight unit, it is possible to further improve the luminance compared to the conventional one, and even if a smaller number of light emitting elements than the conventional backlight unit is used, There is an advantage that it is possible to improve uniformity of luminance.

Particularly, it is possible to reduce the number of light emitting devices compared to conventional backlight units without loss of brightness, and it is possible to realize a display device with reduced material cost and power consumption.

Further, according to one embodiment of the present invention, the reflection plate 122 includes a protrusion 126 protruding from the bottom of the inclined portion at a predetermined height upward.

Here, the protrusion 126 extends in a direction parallel to the row in which the plurality of light emitting devices are disposed, and defines a region where the light source 123 is disposed on the upper portion.

The protruding portion 126 in which the region where the light source portion 123 is disposed is also protruded from the bottom portion of the inclined portion along the row which is parallel to the first rim side a or the second rim side b to a predetermined height h1 And the light emitting element in the light source part 123 is disposed along the extending direction of the protruding part 126.

The light source unit 123 is located at a position higher than the bottom of the inclined portions 122a and 122b of the reflection plate 122 provided at an inclination so as to have a predetermined inclination as it is disposed on the projection 126. [

Accordingly, not only the light emitted horizontally from the light source 123 but also the light emitted from the light source 123 toward the bottom can be reflected by the inclined portions 122a and 122b. The reflectance of the light emitted from the light source 123 can be improved.

When the reflectance of the light emitted from the light source 123 increases, the space in which the light is superimposed and mixed in the space between the light source 123 and the diffusion plate 124 increases, So that the light can be made incident uniformly.

That is, the light source unit 123 is disposed at a position higher than the bottom of the inclined portions 122a and 122b of the reflection plate 122, and at the same time, the inclined portions 122a , 122b can be increased.

As the area of the reflection plate 122 through which the light emitted from the light source 123 can reach increases, the light emission area (coverage area) that can be covered by one light emitting element disposed in the light source 123 also increases. Light can be uniformly directed toward the diffusion plate 124 even if a relatively small number of light emitting devices are used as compared with the conventional backlight unit.

In addition, all the light emitted from the light source 123 is not directly irradiated to the diffusion plate 124, but is reflected by the reflection lens or reflector and is incident on the diffusion plate 124. Even if the spacing h2 between the light source 123 and the diffuser plate 124 is reduced, a region where the light emitted from the light source 123 is concentrated has a higher luminance than other regions, And the possibility of occurrence of unmixed dark areas can be reduced.

11 is a cross-sectional view of a display device according to another embodiment of the present invention.

Referring to FIG. 11, the reflection plate 122 may further include an outer frame part 127 bent upward along the outer frame.

The outer frame part 127 is a part of the reflection plate 122 contacting with the diffusion plate 124 and the outer frame part 127 is formed on each of the first to fourth edge portions a to d, 122a, 122b, 122c, and 122d.

Accordingly, the outer frame section 127 and the first slope section 122a or the second slope section 122b may have a fifth slope? 5 or a sixth slope? 6, and the fifth slope? The sixth inclination [theta] 6 may be set to be equal to or different from each other as needed.

The reflection plate 122 further includes an outer frame part 127 bent upward along the outer frame so that the light reflected from the slope part adjacent to the outer side of the reflection plate 122 can be incident on the outer frame part 127. [ The light incident on the outer frame 127 may be reflected by the other inclined portion of the reflection plate 122 or may be reflected by the diffusion plate 124.

Further, it is preferable that a position where the outer frame unit 127 is formed is positioned below the non-display area NA defined in the display panel 110. Display area NA within the backlight unit 120 as the outer frame unit 127 is positioned below the non-display area NA and reflects the light incident on the diffusion plate 124 at a position corresponding to the lower part of the non- As shown in FIG. In this case, the amount of light incident on the diffusion plate 124 with respect to the amount of light emitted from the light source 123 can be increased, and as a result, the brightness of the displayed image can be improved.

12 to 14 are sectional views of a display device according to various embodiments of the present invention.

12, which is a cross-sectional view of the display device cut along the perforated line A-A ', the reflection plate 122 is inclined so as to have a first inclination [theta] 1 toward the bottom as it goes inward from the first rim side (a) And includes a first inclined portion 122a and a second inclined portion 122b inclined to diagonally lower the second inclination 2 toward the inside toward the second edge side b.

The reflection plate 122 includes two protrusions 126 protruding from the bottoms of the first slopes 122a and the second slopes 122b at a predetermined height upward. Here, the two protrusions 126 extend in a direction parallel to each other, and the extending direction of the protrusion 126 at this time is a direction parallel to the first rim side a and the second rim side b.

In addition, the two protrusions 126 may be spaced apart from each other, and the two protrusions 126 may be connected by the connecting portion 128. The light emitted from the light source unit 123 is reflected by the first inclined portion 122a or the second inclined portion 122b and is incident on the diffuser plate 124 or the connection portion 128 between the two protruded portions 126, And may be incident on the diffuser plate 124.

Referring to FIG. 12, although the connection part 128 is formed as a plane, the connection part 128 may have a shape bent in a "V" shape in consideration of light reflection characteristics, Lt; / RTI >

Referring to FIG. 13, which is a sectional view of the display device cut along the perforated line A-A ', the reflection plate 122 is inclined so as to have a first inclination? 1 toward the bottom as it goes inward from the first rim a. And includes a first inclined portion 122a and a second inclined portion 122b inclined to diagonally lower the second inclination 2 toward the inside toward the second edge side b.

Further, between the first inclined portion 122a and the second inclined portion 122b, a protrusion 126 having a relatively large upper surface as compared with the protrusion 126 shown in FIG. 5 is provided. Also, a light source unit 123 including a plurality of light emitting devices arranged along two rows may be provided on the upper surface of the protrusion 126.

Accordingly, two light emitting device arrays extending in a direction parallel to the first rim side a and the second rim side b may be disposed on the protruding portion 126, and accordingly, the light amount provided from the light source portion 123 It may be possible to increase the luminance.

Referring to FIG. 14, which is a sectional view of the display device cut along the perforated line A-A ', the reflection plate 122 is formed with a slanting slope so as to have a first slope toward the lower side from the first edge side (a) And a second inclined portion 122b inclined so as to angle the second inclination toward the lower side toward the inner side from the first inclined portion 122a and the second edge side b, wherein the first inclination portion and the second inclination portion Can be different.

The protrusions 126 provided at the bottoms of the first inclined portion 122a and the second inclined portion 122b can also be disposed adjacent to the first rim a compared to the second rim b. have.

15 and 16 are sectional views of an outer portion of a display device according to an embodiment of the present invention.

Referring to FIG. 15, the reflection plate 122 includes an outer frame 127 bent upward along the outer frame, and the outer frame 127 may be inclined upward toward the inner side from the outer side. That is, according to the embodiment, the outer frame 127 may be inclined so as to have a slope opposite to the slant of the reflection plate 122.

The light incident on the inclined portion adjacent to the outer side of the reflection plate 122 is reflected toward the inclined surface of the outer frame portion 127 and then reflected by the outer frame portion 127 to be incident on the inclined portion of the reflection plate 122 . The light L3 incident on the outer frame portion 127 provided outside the reflection plate 122 is reflected toward the inclined portion of the reflection plate 122 and then reflected by the reflection plate 122 to be reflected by the diffusion plate 124 It can be made incident.

At this time, it is preferable that the contact surface between the diffusion plate 124 and the outer frame 127 is positioned below the non-display area NA defined in the display panel 110. The light incident on the backlight unit 120 at a position corresponding to the lower portion of the non-display area NA as the contact surface between the diffusion plate 124 and the outer frame 127 is positioned below the non-display area NA, Reflected by the outer frame 127 having a slope in a direction opposite to the tilt of the reflection plate 122 and may be re-incident on the reflection plate 122 or incident on the diffusion plate 124.

Referring to FIG. 16, the reflection plate 122 includes an outer frame 127 bent upward along the outer periphery, and the incident light is totally reflected toward the inclined portion of the reflection plate 122 on the inner side of the outer frame 127 The auxiliary reflecting portion 129 may be disposed. Here, the auxiliary reflecting portion 129 may be provided on the first to fourth edge portions a to d along the rim of the reflection plate 122.

In addition, the auxiliary reflecting portion 129 may include an auxiliary reflecting surface 129a inclined upward from the outside toward the inside. That is, the auxiliary reflecting portion 129 may be inclined with respect to the inclination of the reflection plate 122 in the opposite direction.

The light incident on the inclined portion adjacent to the outer side of the reflection plate 122 may be reflected toward the auxiliary reflection portion 129 and then reflected by the auxiliary reflection plate 129 to be incident on the inclined portion of the reflection plate 122. The light L3 incident on the auxiliary reflecting portion 129 may be reflected toward the inclined portion of the reflecting plate 122 and then reflected by the reflecting plate 122 to be incident on the diffusing plate 124.

At this time, it is preferable that the auxiliary reflecting portion 129 is positioned below the non-display area NA defined in the display panel 110. The light incident on the backlight unit 120 at a position corresponding to the lower portion of the non-display area NA as the auxiliary reflection part 129 is positioned below the non-display area NA is reflected by the inclination of the reflection plate 122 It may be reflected by the auxiliary reflecting portion 129 having an inclination in the opposite direction and re-incident on the reflection plate 122 or incident on the diffusion plate 124.

According to the various modifications of the outer frame 127 described above, it is possible to increase the overlapping and mixing space of the light in the backlight unit 120 and consequently to reduce the uneven brightness of the displayed image. Also, the amount of light incident on the diffusion plate 124 with respect to the amount of light emitted from the light source 123 can be increased, and as a result, the brightness can be improved.

In addition to the light directly emitted from the light source unit 123 toward the display area AA adjacent to the non-display area NA, the light is emitted after being emitted to the outer frame 127, The possibility of occurrence of a dark portion in a rim portion of the non-display area NA can be reduced by the light incident on the non-display region NA.

As described above, the backlight unit according to various embodiments of the present invention and the display device including the backlight unit according to various embodiments of the present invention have a variety of outgoing angles from the light source by arranging the light sources at positions higher than the bottom of the reflector provided at an inclination so as to have a predetermined inclination The reflectance of the emitted light can be increased.

Accordingly, the overlapping and mixing space of the light in the backlight unit can be increased, and the coverage area by one light source can be widened, thereby narrowing the interval between the light source and the display panel, thereby providing a thin display device. In addition, even if the number of light emitting elements used in the backlight unit is reduced, light can be uniformly directed toward the diffusion plate, and a low cost and lightweight display device can be realized.

While the present invention has been particularly shown and described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. It is therefore to be understood that such changes and modifications are intended to be included within the scope of the present invention unless they depart from the scope of the present invention.

Claims (16)

A reflection plate including an inclined portion inclined downward toward the inside from the outside to the inside and at least one protruding portion protruding from the bottom of the inclined portion toward the top at a predetermined height;
A light source unit provided on the protrusion and including a plurality of light emitting elements arranged along at least one row and a reflective lens covering an upper portion of the light emitting element; And
A diffusion plate provided on the reflection plate;
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Backlight unit.
The method according to claim 1,
Wherein the protrusions extend in a direction parallel to a row in which the plurality of light emitting elements are arranged,
Backlight unit.
The method according to claim 1,
Wherein the reflective lens has a reflective surface facing the light emitting element and the light emitted from the light emitting element toward the reflective surface is transmitted through the reflective lens toward the diffuser plate or totally reflected toward the reflective plate according to an incident angle,
Backlight unit.
The method according to claim 1,
The reflective lens covers all the upper portions of the plurality of light emitting elements arranged in one column.
Backlight unit.
The method according to claim 1,
Wherein the reflector further comprises an outer frame portion bent upwardly along an outer periphery thereof,
Backlight unit.
6. The method of claim 5,
Wherein the outer frame portion is inclined toward the upper portion from the outer side toward the inner side,
Backlight unit.
6. The method of claim 5,
And an auxiliary reflecting portion for reflecting the incident light to the reflecting plate is disposed inside the outer frame.
Backlight unit.
8. The method of claim 7,
Wherein the auxiliary reflecting portion includes an auxiliary reflecting surface inclined upward toward the inside from the outside to the inside,
Backlight unit.
The method according to claim 1,
The rim of the reflection plate in contact with the diffusion plate includes a first rim and a second rim opposite to each other, and a third rim and a fourth rim that connect the first rim and the second rim respectively, ,
The reflector has a first inclined portion inclined to have a first inclination toward the lower portion toward the inside toward the first edge of the frame, and a second inclined portion inclined to the second inclined portion toward the lower portion toward the inside toward the second edge, And a second inclined portion,
Wherein the first slope and the second slope are the same or different,
Backlight unit.
10. The method of claim 9,
The reflector has a third inclined portion inclined to have a third inclination toward the lower portion toward the inside toward the third edge, and a third inclined portion inclined toward the lower portion toward the lower portion to be inclined to the fourth inclined portion And a fourth inclined portion,
Backlight unit.
A reflection plate including an inclined portion inclined downward toward the inside from the outside to the inside and at least one protruding portion protruding from the bottom of the inclined portion toward the top at a predetermined height;
A lower cover inclined to correspond to a lower surface of the reflection plate;
A light source unit provided on the protrusion and including a plurality of light emitting elements arranged along at least one row and a reflective lens covering an upper portion of the light emitting element; And
A diffusion plate provided on the reflection plate;
A display panel provided on the diffusion plate;
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Display device.
12. The method of claim 11,
Wherein the protrusions extend in a direction parallel to a row in which the plurality of light emitting elements are arranged,
Display device.
12. The method of claim 11,
Wherein the reflector further comprises an outer frame portion bent upwardly along an outer periphery thereof,
Display device.
14. The method of claim 13,
The outer frame portion is inclined upward toward the inner side from the outer side,
Wherein a contact surface between the diffusion plate and the outer frame is located below a non-display area defined in the display panel,
Display device.
14. The method of claim 13,
An auxiliary reflecting portion for reflecting the incident light to the reflecting plate is disposed inside the outer frame,
Wherein the auxiliary reflector is located below a non-display area defined in the display panel,
Display device.
16. The method of claim 15,
Wherein the auxiliary reflecting portion includes an auxiliary reflecting surface inclined upward toward the inside from the outside to the inside,
Display device.

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