KR20110139039A - Display apparatus - Google Patents

Abstract

PURPOSE: A display apparatus is provided to reduce the thickness of a display module by eliminating a conductive layer material. CONSTITUTION: A display apparatus includes a backlight unit(23) and a display panel. The backlight unit includes a substrate layer(231), a reflection layer(232), a pattern layer, and a common layer(233). A light source is located on a substrate. A reflection layer is formed on the substrate. The reflection layer reflects the light of the light source. The pattern layer is located on the upper side of the light source. The common layer is formed between the reflection layer and the pattern layer.

Description

Display apparatus

The present invention relates to a display device.

Liquid crystal display devices have been used in various fields as well as notebook PC and monitor market due to small size, light weight and low power consumption.

The liquid crystal display device includes a liquid crystal panel and a backlight unit. The backlight unit provides light to the liquid crystal panel, and the light passes through the liquid crystal panel. At this time, the liquid crystal panel implements an image by adjusting the light transmittance.

The backlight unit may be divided into an edge type and a direct type according to the shape of the light source. In the edge type, the light source may be disposed on the side of the liquid crystal panel, and the light guide plate may be disposed on the rear side of the liquid crystal panel to guide light provided from the side of the liquid crystal panel to the rear side of the liquid crystal panel. The direct type may include a plurality of light sources on the back of the liquid crystal panel, and light emitted from the plurality of light sources may be directly provided to the back of the liquid crystal panel.

As such a light source, an electro luminescence (EL), a cold cathode fluorescent lamp (CCFL), a hot cathode fluorescent lamp (HCFL), a light emitting diode (LED), or the like may be used. Among these, LEDs may have advantages of low power consumption and excellent luminous efficiency.

An object of the present invention is to provide a display device capable of achieving luminance and color uniformity without using a light guide layer constituting a backlight unit.

According to another aspect of the present invention, there is provided a display apparatus including a display panel and a backlight unit providing light from the rear of the display panel, wherein the backlight unit includes: a light source; A substrate layer on which the light source is seated; A reflection layer formed on the substrate layer to reflect light emitted from the light source; A pattern layer placed on an upper surface of the light source; And a vacant layer formed between the reflective layer and the pattern layer.

According to the display device according to the embodiment of the present invention having the above configuration, the following effects are obtained.

First, color uniformity is improved by applying a patterned metal reflector (PMR) layer according to an embodiment of the present invention.

Secondly, by removing the existing light emitting layer function as a light guide layer, there is an advantage that can achieve a lighter weight of the display module, and further has the advantage of reducing the manufacturing cost.

Third, the light guide layer of the resin material, the reflection pattern of the reflection sheet causing color problems, and the reflection pattern of the white ink material causing light scattering are removed, thereby maximizing light utilization efficiency and achieving brightness and color uniformity. There is an advantage.

Fourth, since the brightness is increased to obtain a high-quality image, there is an advantage that can secure the competitiveness of the product.

Fifth, since the existing light guide layer material is removed, the display module can be made ultra thin.

1 is an exploded perspective view of a display device according to an embodiment of the present invention.
2 is a cross-sectional view schematically showing the configuration of a display device according to an embodiment of the present invention.
3 is a cross-sectional view showing a detailed structure of a display module according to an embodiment of the present invention.
4 is a plan view of a reflective layer constituting a backlight unit according to an embodiment of the present invention;
5 is a plan view showing a PMR layer according to an embodiment of the present invention.
FIG. 6 is an enlarged view of area A of FIG. 5; FIG.
7 is a view showing a movement path of light generated inside the display module according to an embodiment of the present invention.
8 is a plan view of a reflective layer constituting a backlight unit according to an embodiment of the present invention;
9 is a view showing a movement path of light generated inside a backlight unit having a reflective layer and a PMR layer according to an embodiment of the present invention.
10 is a cross-sectional view showing a display module according to another embodiment of the present invention.
11 is a cross-sectional view illustrating a method of forming a PMR layer according to another embodiment of the present invention.
12 is a plan view showing a light source arrangement of the backlight unit according to another embodiment of the present invention.
13 is a plan view showing a light source arrangement of a backlight unit according to another embodiment of the present invention.
14 is a plan view showing a light source arrangement of the backlight unit according to another embodiment of the present invention.
15 and 16 are plan views illustrating embodiments of a structure of a reflective layer included in a backlight unit according to another exemplary embodiment of the present invention.
17 is a side cross-sectional view for explaining a positional relationship between a light source and a reflective layer provided in the backlight unit according to the embodiment of the present invention.
18 is a side view illustrating a structure of a light source provided in the backlight unit.
19 is a side sectional view showing a structure for supporting a PMR layer in a backlight unit according to an embodiment of the present invention.
20 is a plan view of a backlight unit having a structure for supporting the PMR layer.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is an exploded perspective view of a display device according to an exemplary embodiment of the present invention.

Referring to FIG. 1, a display device 1 according to an embodiment of the present invention includes a front cover 10; A display module 20 provided on a rear surface of the front cover 10; A heat dissipation member 30 provided on a rear surface of the display module 20; A back cover 40 accommodating the display module 20 and the heat dissipation member 30; A driving unit 60 coupled to a rear surface of the back cover 40; The drive unit 60 includes a chassis 50 for fixing the back cover 40 and a drive unit cover 70 covering the drive unit 60.

In detail, the display module 20 includes a display panel 21 on which an image is implemented, and a backlight unit 23 that provides light forward from the rear surface of the display panel 21. In addition, the driving unit 60 disposed on the rear surface of the back cover 40 may include a power supply unit 61, a main board 62, and a driving control unit 63. In addition, the driving unit 60 may be fixed to the rear surface of the back cover 40 by the chassis 50. In addition, the driving controller 63 may be a timing controller, and adjusts an operation timing of each driving circuit of the display panel 21. In addition, the main board 62 is a portion that transmits V sink, H sink, and R, G, B resolution signals to the timing controller, and the power supply 61 is the display panel 21 and the backlight unit 22. ) To apply power. In addition, the driving unit 60 may be wrapped by the driving unit cover 70 to block external exposure.

In addition, a heat dissipation member 30 is interposed between the display module 20 and the back cover 40 to improve the heat dissipation effect of heat generated from the display module 20 and the driving unit 60.

In addition, the front cover 10 may have an opening having a predetermined size therein, and may have a rectangular band shape having a predetermined width, or may have a rectangular plate shape covering all of the front surface of the display module 20. In the former case, not only the front edge of the display module 20 in which the image is not output, but also the edge portion of the display module 20 can be prevented from being damaged from external force. In the latter case, as a transparent plate that transmits light, the resin may be a plastic panel or compression-strengthened glass formed by injection compression molding. In addition, an opaque film layer or a coating layer is surrounded by an edge of the front cover 10 to cover an edge portion of the display module 20 in which light is not emitted.

Hereinafter, the structure of the display module 20 and the mounting structure of the driver 60 will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view schematically illustrating a configuration of a display apparatus according to an exemplary embodiment of the present invention.

Referring to FIG. 2, the front cover 10 is placed on the frontmost side (the topmost side in the drawing), and the display module 20, the heat dissipation member 30, and the back cover 40 are coupled to the rear side. In addition, the driving unit 60 is mounted to the rear surface of the back cover 40 by the chassis 50. The driver 60 is covered by the driver cover 70.

The display module 20 includes a display panel 21 and a backlight unit 23.

3 is a cross-sectional view showing a detailed structure of a display module according to an embodiment of the present invention.

Referring to FIG. 3, the display module 20 according to the embodiment of the present invention includes a display panel 21 and a backlight unit 23.

In detail, the display panel 21 is a part in which an image is implemented, and a polarizing plate is placed on front and rear surfaces (upper and lower surfaces in the drawing), and a plurality of substrates are interposed therebetween. One of the plurality of substrates may be referred to as a TFT array substrate, and a plurality of pixels may be defined by crossing a plurality of scan lines and data lines in a matrix shape. Each pixel may include a thin film transistor (TFT) for turning a signal on and off, and a pixel electrode connected to the thin film transistor may be positioned. The other one of the plurality of substrates may be referred to as a color filter substrate, and the red (R), green (G), and blue (B) color filters corresponding to the plurality of pixels may be surrounded by a scan line and A black matrix may be provided to cover non-display elements such as data lines and thin film transistors. The edge of the display panel 21 may be provided with a gate driver and a data driver for generating a driving signal for driving the display panel 21.

On the other hand, the backlight unit 23 according to the embodiment of the present invention is placed on the rear (lower side in the drawing) of the display panel 21.

In detail, the backlight unit 23 may include a circuit board layer 231 including a PCB substrate from a lowermost layer, a plurality of light sources 24 mounted on the substrate layer 231, and the substrate. A reflection layer 231 formed on an upper surface of the layer 231, a PMR layer 234 spaced apart from the reflective layer 232 and disposed on an upper surface of the light sources 24 and the reflection layer 231. And a diffusion layer 235 overlying the PMR layer 234.

The light source 24 may be one of a light emitting diode (LED) chip or a light emitting diode package (hereinafter, referred to as an LED package) having at least one light emitting diode chip. In this embodiment, an LED package as the light source 24 will be described as an example.

The LED package constituting the light source 24 may be divided into a top view method and a side view method according to a direction in which the light emitting surface faces, and the light source 24 according to an embodiment of the present invention The light emitting surface may be configured using at least one of the LED package of the top view type formed toward the upper side and the LED package of the side view type formed to the side.

In the present embodiment, when the light source 24 is a side view type LED package, the light emitting surfaces of the plurality of light sources 24 are disposed on side surfaces, respectively, and are parallel to the side surface, that is, the substrate layer 231. It can emit light in one direction. Therefore, the backlight unit 23 and further, the display device 1 can be made slimmer.

In addition, the light source 24 may be a colored LED or a white LED emitting at least one of colors such as red, blue, and green. In addition, the colored LED may include at least one of a red LED, a blue LED, and a green LED, and the arrangement and emission light of the light emitting diode may be variously changed and applied.

The display panel 21 may be simply mounted on the diffusion layer 235 or may be attached by an adhesive layer. The diffusion layer 235 serves to diffuse light emitted from the light sources 24 toward the upper side, that is, toward the display panel 21. In addition, the diffusion layer 235 may be provided in the form of an optical sheet. For example, the optical sheet may be configured by stacking one or more diffusion sheets 235a and one or more prism sheets 235b. At this time, the diffusion layer 235, that is, the plurality of sheets constituting the optical sheet may be provided in a state in which they are bonded or adhered to each other without being spaced apart from each other, thereby reducing the thickness of the backlight unit 23. The diffusion layer 235 may not only be provided in a form in which the prism sheet 235b and the diffusion sheet 235a are combined, but only one or more diffusion sheets 235a may be provided, or one or more prism sheets ( 235b) may also be provided. In addition, the diffusion layer 235 may further include various functional layers in addition to the prism sheet 235b and the diffusion sheet 235a. The diffusion sheet 235a may diffuse the incident light to prevent the light emitted from the light guide layer 233 from being partially concentrated, thereby making the luminance of the light more uniform. The prism sheet 235b may collect light from the diffusion sheet 235a to allow light to enter the display panel 21 vertically.

In addition, a vacant layer 233 is formed between the reflective layer 232 and the PMR layer 234 to fill the air or maintain a vacuum state. In the conventional backlight unit, a light guiding layer of a resin material is provided in order to diffuse and reflect light emitted from the light source 24, but the embodiment of the present invention omits the light guiding layer of the resin material. It is characterized by. In the case of a display device in which a separate light guide plate is essentially provided, there is a limit in reducing the thickness, weight, and manufacturing cost of the display module.

In addition, the present invention is applied to the PMR layer 234 instead of the screening layer (screening layer) that was mainly applied in the past, instead of the light extraction layer (light extraction layer) provided on the upper surface of the substrate layer 231, the reflectance is even and the reflectance is The reflective layer 232 coated with a high metallic reflection material was applied. Thus, light emitted from the light source is repeatedly reflected between the reflective layer 232 and the PMR layer 234, so that the light propagates effectively. In addition, the PMR layer 234 is formed with a reflection area and a transmission area (described later), and light that hits the reflection area is specularly reflected by the reflection layer 232, and light that hits the transmission area is It propagates through the PMR layer 234 to the diffusion layer 235. The reflective layer 232 may be a dielectric multi-layer in which a plurality of layers having different refractive indices, in addition to the mirror reflecting metal sheet, may be formed.

Meanwhile, in the case of a backlight unit provided with a separate light guide layer and a light blocking layer, a total reflection phenomenon occurs at an interface between the light guide layer and the light blocking layer. In detail, when light enters a material having a high refractive index from a material having a small refractive index, light incident at an incident angle greater than a critical angle is completely reflected without refraction. For this reason, the phenomenon in which the uniformity of light distribution falls is produced. In addition, in order to minimize such a problem, inevitably, patterns for scattering light inside the light guide layer are additionally required. That is, the light scattering particles may be inserted into the light guide layer, or a reflective pattern may be formed on the upper surface of the substrate layer, or the light extraction layer on the upper surface of the substrate layer may be formed of a white reflective sheet.

However, in the case of the present invention, the light guide layer does not need to be formed separately. That is, since the portion where the light guide layer is interposed is maintained in the air layer or the vacuum layer state, total reflection does not occur due to the difference in refractive index. That is, in the PMR layer 234, only light reflection and transmission phenomena occur and total reflection of light does not occur, so that color problems do not occur. In addition, the ratio of the transmission region and the reflection region formed in the PMR layer 234 may be appropriately adjusted mathematically, thereby controlling the distribution of transmitted light. On the contrary, in the case of a display module in which a separate light blocking layer and a light guide layer are stacked, even if the size (or ratio) of the transmission / reflection region of the light blocking portion is adjusted, the desired amount of light is transmitted due to the total reflection phenomenon. It is practically difficult to control to reflect.

4 is a plan view of a reflective layer constituting a backlight unit according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the backlight unit 22 may include two or more light sources emitting light in different directions.

That is, the light sources 24a and 24b included in the first light source array and the light sources 24c and 24d included in the second light source array may emit light in different directions. In other words, the direction in which the light emitting surfaces of the light sources 24, 24b included in the first light source array face each other and the direction in which the light emitting surfaces of the light sources 24c, 24d included in the second light source array face each other may be different from each other. In this case, the light sources provided in the backlight unit 22 may emit light in the lateral direction, respectively, and may be configured by using a side view type LED package.

On the other hand, as shown, a plurality of light sources provided in the backlight unit 22 may be arranged to form two or more rows, two or more light sources arranged in the same row may emit light in the same direction.

FIG. 5 is a plan view illustrating a PMR layer according to an exemplary embodiment of the present invention, and FIG. 6 is an enlarged view of region A of FIG. 5.

5 and 6, the PMR layer 234 according to the embodiment of the present invention has a reflection region 234a and a transmission region 234b.

In detail, the PMR layer 234 may be a reflection / transmission modulation film in which the reflection region 234a and the transmission region 234b are mixed. In addition, the reflective region 234a is coated with a metallic reflective material capable of specular reflection, so that the light hitting the reflective region 234a is reflected at the same angle as the incident angle. The transmission region 234b is a transparent region through which light can pass, and the light transmitted to the transmission region 234b passes through the PMR layer 234 as it is and is transmitted to the diffusion layer 235.

On the other hand, the light transmission region 234b may be a two-dimensional shape having a predetermined area, as shown, a plurality of light transmission region 234b may be gathered to form a pattern of any shape. . The pattern may be formed irregularly, as shown in Figure 4, may be formed to be repeated periodically. In addition, by adjusting the area ratio of the reflective region 234a and the transmissive region 234b, the light transmittance can be adjusted. In addition, luminance uniformity may be achieved by adjusting the shape of the transmission region 234a pattern, that is, the size of each transmission region 234b. For example, in a region close to the light source, the size of each transmission region 234b may be reduced to reduce the area of the transmission pattern so that a hot spot phenomenon does not occur. On the contrary, by increasing the area of the transmission pattern as the distance from the light source increases, the light uniformity can be achieved with respect to the entire area of the display panel.

In this embodiment, the PMR layer 234 is formed by making the portion corresponding to the transmissive region 234b in the mirror reflective metallic reflection sheet to be perforated. In other words, the transmission region 234b has a through hole shape, and the light incident to the transmission region 234b passes through to reach the diffusion layer 235. Part of the light reaching the diffusion layer 235 may be advanced toward the display panel 21, and part of the light may be reflected and returned to the reflective layer 232. The light guiding or light propagation process of the light emitted from the light source will be described in detail with reference to the accompanying drawings.

As such, a backlight unit structure according to an embodiment of the present invention, that is, a mirror reflecting metallic reflecting sheet and a PMR layer 234 performing only reflection and transmission functions, are provided therebetween, and a cavity layer in the form of an air layer or a vacuum layer ( According to the backlight unit structure in which the vacant layer 233 is formed, the light emitted from the light source is diffused to the side of the display module through the reflection, transmission, and re-reflection processes. In addition, the total reflection phenomenon does not occur at the interface between the cavity layer 233 and the PMR layer 234.

7 is a view showing a movement path of light generated inside the display module according to an exemplary embodiment of the present invention.

Referring to FIG. 7, light emitted from the light source 24 is spread with a predetermined angle of directivity. A portion of the light emitted from the light source 24 is reflected by the diffusion layer 232 and moved to the PMR layer 234. At this time, the light that strikes the diffusion layer 234 is specular reflection (specular reflection) at the same angle as the incident angle. The light that strikes the reflective region 234a among the light moving to the PMR layer 234 is mirror-reflected and reincident to the reflective layer 232. Through such reflection and re-reflection, light propagates in the horizontal direction from the light source. In addition, the light reaching the transmissive region 234b among the light moving to the PMR layer 234 passes through the PMR layer 234 to the diffusion layer 235. A portion of the light traveling to the diffusion layer 235 moves forward to the display panel 21, and a portion of the light is reflected back to return to the cavity layer 233. As the distance from the light source 24 increases, the size of the transmission region 234b increases and the distance between adjacent transmission regions 234b decreases, so that light emitted from the light source is uniformly distributed throughout the display panel. You can do that.

8 is a plan view of a reflective layer constituting a backlight unit according to an exemplary embodiment of the present invention, and FIG. 9 is a view illustrating a movement path of light generated inside a backlight unit having a reflective layer and a PMR layer according to an exemplary embodiment of the present invention. .

8 and 9, a plurality of light sources 24 are disposed on the upper surface of the substrate layer 231 constituting the backlight unit 23 according to an embodiment of the present invention at regular intervals, and the light sources ( The reflective layer 232 to which the reflective material is applied is formed at a portion other than the portion 24 is disposed.

Most of the structure of the backlight unit provided with a separate light guide layer is a form in which a white light extraction layer and a metal pattern are formed on the upper surface of the substrate layer, or vice versa. Here, when the light extraction layer is formed of the white reflective sheet and the metallic reflective pattern, or the metallic reflective sheet and the white reflective pattern, color problems due to different materials may occur. In particular, in the case of a white reflective sheet, light may be scattered and hot spots may occur in an area around a light source.

In this embodiment, the upper surface of the substrate layer is characterized in that the reflective layer 232 is formed of a metal sheet or a dielectric multi-layer that mirror-reflects. Therefore, the light emitted from the light source 24 in the lateral direction of the display module 20 proceeds with a directivity angle. In addition, a portion of the traveling light hits the reflective layer 232 to reflect the mirror. Since the reflective layer 232 is a metal reflective sheet, light is reflected at the same angle as the incident angle. In addition, another portion of the traveling light directly strikes the PMR layer 234. A portion of the light that strikes the PMR layer 234 is mirror-reflected by hitting the reflective region 234a, and a portion of the light is moved toward the display panel 21 through the transmissive region 234b. That is, the light emitted from the light source 24 propagates in the horizontal direction in the cavity layer 233 while repeating the reflection between the lower reflective layer 232 and the upper PMR layer 234. In this propagation process, light moves forward through the transmission region 234b of the PMR layer 234. Therefore, the amount of light emitted toward the display panel 21 can be adjusted by adjusting the area ratio between the transmission region 234b and the reflection region 234a formed in the PMR layer 234. In addition, the brightness of the light may be adjusted by appropriately setting the pattern of the transmission region 234b to adjust the amount of transmitted light.

In addition, as described above, total reflection does not occur in the boundary region of the cavity layer 233 and the PMR layer 234 or in the boundary region of the cavity layer 233 and the reflective layer 232, thereby improving uniformity of light distribution. It has the advantage of being.

On the other hand, as shown in the reflection layer 232, in order to increase the amount of light passing through the PMR layer 234 in the display panel 21 direction, that is, in the front direction of the display device, that is, The reflective pattern 232a may be formed. The reflective pattern 232a may be made of the same material as the material of the reflective layer 232. That is, it may be made of a metallic reflective sheet or a dielectric thin film stack structure.

According to the structure as described above, when the light moving in the horizontal direction through the mirror reflection on the reflective pattern 232a is reflected at an angle different from the incident angle. As a result, a portion of the light incident at an oblique angle with a directivity angle may be reflected toward the display panel 21, so that the amount of light passing through the PMR layer 234 may increase.

The reflective pattern 232a may be formed at a predetermined distance and a distance, but is not limited thereto. As another example, a plurality of reflective patterns 232a may be formed in the reflective layer 232, and the distance between adjacent patterns 232a may be narrower as the distance from the light source 24 increases. Further, as the distance from the light source increases, the width of the pattern 232a may be expanded, for example, in the form of a triangle or a fan.

As shown in FIG. 8, a plurality of reflective patterns 232a may be formed to facilitate propagation of light emitted from the light source 24 to an adjacent light source. The reflective patterns 232a reflect light emitted from the light source 24 at various angles different from the incident angle, so that the light moves toward the display panel 21. In other words, light emitted laterally from the light source 24 can be extracted and moved toward the display panel 21.

Specifically, the backlight unit 23 may include two or more light source arrays that emit light in different directions. That is, a first light source array including a first light source 24a and a second light source 24b disposed in the + X axis direction on the drawing, and a third light source 24c and the fourth light source disposed in the −X axis direction. The second light source array including 24d may be alternately arranged a plurality of times in the y-axis direction.

As such, by forming the first light source array and the second light source array in opposite directions in the light emission direction, the phenomenon in which the luminance of the light is concentrated or weakened in a specific region of the backlight unit 23 can be reduced.

In detail, the plurality of reflective patterns 232a may be disposed in a shape as shown to prevent hot spots from being observed near the light source or weakening of the brightness far from the light source. That is, as the distance from the light source toward the direction of light increases, the density of the reflective patterns 232a increases and the distance between the patterns decreases, so that the adjacent other light sources 24b far from any one of the light sources 24a and 24c. It is possible to prevent the luminance from decreasing in the rear region of (24d), which may be advantageous in terms of luminance uniformity.

In other words, in the region close to the light source, the number of the reflective patterns 232a is reduced so that the light emitted from the light source 24 is mirror-reflected by the reflective layer 232 and spread away. On the contrary, as the distance from the light source increases, the number of the reflective patterns 232a is increased, thereby increasing the reflection frequency of light and varying the reflection angle. Then, the luminance of the light between the region near and far from the light source can be kept uniform.

The shape or arrangement structure of the reflective pattern 232a is not limited to the present embodiment, and various embodiments may be proposed.

10 is a cross-sectional view illustrating a display module according to another embodiment of the present invention.

Referring to FIG. 10, the present embodiment is mostly the same as the embodiment shown in FIG. 3, but there is a difference in the method of forming the PMR layer.

In detail, the PMR layer according to the present embodiment is not provided in the form of an independent metal sheet, but the bottom surface (or Back). In other words, in the previous embodiment, a portion corresponding to the reflective region 234a is formed on the bottom surface of the diffusion layer 235. Accordingly, the PMR pattern 334 may be provided on the bottom surface of the diffusion layer 235 by a printing technique using deposition, coating, or metal ink.

11 is a cross-sectional view illustrating a method of forming a PMR layer according to another embodiment of the present invention.

Referring to FIG. 11, the PMR layer 434 according to the present embodiment is characterized in that the PMR pattern 434b (or reflection pattern) is formed on a transparent film paper 434a by deposition, coating, or printing technique. . In other words, there is a slight difference in the formation method from that in which the transmissive region is perforated in some regions of the metallic reflective sheet.

In addition, the PMR pattern 434b may be formed on the transparent sheet, and the PMR layer may be formed by removing a reflective material applied to a portion of the film paper to which the metallic reflective material is to be applied. In other words, using a photo-litho technique, the PMR layer may be formed by raising the reflective layer on the transparent film and removing the reflective material to form the transmissive region.

12 is a plan view illustrating a light source arrangement of a backlight unit according to another exemplary embodiment of the present invention.

Referring to FIG. 12, the first light source array and the second light source array may be arranged on the same line in the y-axis direction. The light sources may be arranged to emit light from the first light source array and the second light source array in the same direction or in opposite directions.

13 is a plan view illustrating a light source arrangement of a backlight unit according to another exemplary embodiment of the present invention.

Referring to FIG. 13, the light emitting surfaces of the light sources constituting the first light source array and the second light source array may be formed obliquely upward or downward by a predetermined angle with respect to the x-axis extension line.

14 is a plan view illustrating a light source arrangement of a backlight unit according to another embodiment of the present invention.

Referring to FIG. 14, a plurality of light source arrays may be spaced apart from each other based on the y axis.

In detail, in the present embodiment, the third light source arrays 24e and 24f are further added to the first and second light source arrays, and the light sources 24a, 24c and 24e constituting each of the light source arrays are each other with respect to the y axis. It is spaced apart at different intervals. That is, a single light source 24a constituting the first light source array among the light sources 24a, 24c, and 24e constituting each of the light source arrays is disposed farthest from the y axis, and constitutes a single light source constituting the third light source array. The light source 24e may be configured to be disposed closest to the y axis.

15 and 16 are plan views illustrating an embodiment of a structure of a reflective layer included in a backlight unit according to another exemplary embodiment of the present invention.

The reflective layer 232 provided in the backlight unit 22 according to the embodiment of the present invention may have two or more reflectances. For example, the reflectance of the reflective layer 232 may be configured to have different reflectances according to the formed position. Can be. That is, the reflective layer 232 may include two or more regions having different reflectances.

Referring to FIG. 15, the light sources 24 may be formed at positions overlapping the boundary portion between the first reflective layer 232b and the second reflective layer 32b, respectively.

In addition, referring to FIG. 16, the light sources 24 may be positioned within a region where the first reflective layer 232b is formed by being spaced apart from the boundary between the first reflective layer 232b and the second reflective layer 232c by a predetermined interval. have.

According to the exemplary embodiment of the present invention, a gradation region in which the reflectance gradually increases or decreases may be formed at the boundary portion between the first and second reflecting layers 232b and 232c having different reflectances.

Also, although not shown, the light sources 24 may of course be located in the second reflective layer 232c region.

17 is a side cross-sectional view for describing a positional relationship between a light source and a reflective layer included in the backlight unit according to the exemplary embodiment of the present invention.

Referring to FIG. 17, as the reflective layer 232 is disposed on the upper surface of the substrate layer 231, light emitted from the light source 24 to the side surface is reflected from the reflective layer 232 to the PMR layer 234.

The light source 24 may include a light emitting part k for emitting light, and the light emitting part k may be positioned at a predetermined height c from the surface of the substrate layer 231. Here, the thickness b of the reflective layer 232 may be equal to or smaller than the height c of the light emitting unit 222, so that the light source 24 may be positioned above the reflective layer 232.

For example, the thickness c of the reflective layer 232 may be 0.02 mm to 0.08 nm or less. Here, when the thickness c of the reflective layer 232 is 0.02 mm or more, the reflective layer 232 may achieve a light reflectance in a reliable range, and when the thickness c of the reflective layer 232 is 0.08 mm or less, There is an advantage that the light emitted from the light source 24 can be prevented from being lost by covering the light emitting portion k of (24). Therefore, in order for the reflective layer 232 to improve the incident efficiency of the light emitted from the light source 24 and to reflect most of the light incident from the light source 24, the thickness b of the reflective layer 232 may be 10 nm to 10 nm. It may be formed to 100㎛.

18 is a side view illustrating a structure of a light source provided in the backlight unit.

Referring to FIG. 18, the light source 24 may include a light emitting device 241 that emits light, a mold part 242 having a cavity 243, and a plurality of lead frames 244 and 245. .

In detail, the light emitting device 241 may be a light emitting diode chip (LED chip), the light emitting diode chip is composed of a blue LED chip or an ultraviolet LED chip or a red LED chip, green LED chip, blue LED chip, yellow green (Yellow green) It may be configured in a package form combining at least one or more of the LED chip, white LED chip. The light emitting device 241 may be classified into a horizontal type and a vertical type according to a structure. In the present invention, since a backlight unit having a structure in which light is emitted laterally is applied, a vertical type may be applied.

19 is a side cross-sectional view illustrating a structure of supporting a PMR layer in a backlight unit according to an exemplary embodiment of the present invention, and FIG. 20 is a plan view of a backlight unit having a structure supporting the PMR layer.

Referring to FIG. 19, a cavity layer 233 is formed between the PMR layer 234 and the reflective layer 232. In other words, since an empty space is formed between the PMR layer 234 and the reflective layer 232, the PMR 234 layer may be substantially supported by the light sources 24. The PMR layer 234 is manufactured to be in close contact with the diffusion layer 235 or to minimize the bending, but the phenomenon of sagging toward the cavity layer 233 may not be excluded. Therefore, in order to prevent such deflection, a plurality of supports 30 may be provided inside the cavity layer 233.

In detail, the support part 30 may be made of a transparent material through which light may pass, and may be made of a light transmissive material, for example, silicone or acrylic resin (PMMA).

In addition, the support part 30 may be disposed in a space between a plurality of light source arrays. When the support 30 is disposed inside the light source array, the light emitted from each light source 24 may be refracted before reaching the reflective layer 24. Then, some of the refracted light may not move toward the PMR layer 234 and may travel in a direction parallel to the reflective layer 232. Therefore, the support part 30 may be installed in a space between adjacent light source arrays.

In addition, the support portion 30 may be made in the form of narrowing toward the top. That is, the outer peripheral surface of the support 30 is formed to be inclined, so that the light emitted from the light source 24, the light reflected from the reflective layer 232, or the light reflected back from the PMR layer 234 in various directions. Can be refracted and totally reflected.

In addition, the cross-sectional shape of the support part 30 may be a circular cross section as shown, but may have a polygonal cross section of three or more triangles. Since the cross-sectional shape of the support part 30 is polygonal, incident light may be refracted and reflected in various directions.

In addition, the upper surface of the support 30 is in close contact with the reflective region 234a of the PMR layer 234 so as not to interfere with the transmission of light from the PMR layer 234 to the diffusion layer 235. It is good.

In addition, each of the supporting parts 30 is disposed in an area that is 1/2 of the distance between the light source arrays adjacent in the y-axis direction and / or an area that is 1/2 of the distance between the light source arrays adjacent in the x-axis direction. In this case, the PMR layer 234 may be stably supported. However, it should be noted that the placement position of the supports 30 is not limited to the embodiment shown.

Claims (11)

A display panel and a backlight unit for providing light from the rear of the display panel,
The backlight unit,
Light source;
A substrate layer on which the light source is seated;
A reflection layer formed on the substrate layer to reflect light emitted from the light source;
A pattern layer placed on an upper surface of the light source; And
And a vacant layer formed between the reflective layer and the pattern layer. The method of claim 1,
The cavity layer comprises an air layer or a vacuum layer,
The pattern layer includes a patterned metal reflection layer (PMR) including a reflective region for reflecting light and a transmissive region for transmitting light. The method of claim 2,
And a specular reflection is generated at the boundary portion of the cavity layer and the PMR layer and at the boundary portion of the cavity layer and the reflective layer without light total reflection or refraction. The method of claim 2,
The reflective region and the reflective layer of the PMR layer includes a metallic reflective material or a dielectric multi-layer having an even reflectivity and a high reflectance. The method of claim 4, wherein
On the upper surface of the reflective layer, a reflection pattern for adjusting the reflection angle of light is formed,
And the reflective pattern includes a metallic reflective material or a dielectric stacked structure. The method of claim 1,
And the PMR layer is a reflection / transmission modulation film in which a transmission hole for transmitting light is formed in a film made of a metallic reflective material. The method of claim 2,
And the PMR layer is a reflection / transmission modulation film formed of a form in which a metallic reflective material reflecting light is applied to a portion of the transparent film. The method of claim 7, wherein
And the metallic reflective material is applied to the transparent film by any one of deposition, coating and printing techniques. The method of claim 2,
Further comprising a diffusion layer in the form of an optical sheet lying on the upper surface of the PMR layer,
And the PMR layer is a reflective pattern deposited, coated or printed on the bottom of the diffusion layer. The method of claim 2,
Any one of the reflective region and the transmissive region of the PMR layer gathers to form a pattern,
And the pattern is repeatedly arranged with periodicity. The method of claim 2,
And a support interposed between the reflective layer and the PMR layer.

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