KR101837775B1 - Liquid Crystal Display - Google Patents

Abstract

A liquid crystal display according to an embodiment of the present invention includes a liquid crystal display panel including an image display unit; A top cover extending from the bezel portion and guiding a side surface of the liquid crystal display panel, the bezel portion including a bezel portion surrounding an edge of the image display portion; A guide panel which overlaps with the bezel portion of the top cover and guides a bottom edge of the liquid crystal display panel; A light guide plate disposed on the lower surface of the liquid crystal display panel so as to overlap with the guide panel; An LED assembly disposed to face one side of the light guide plate; An LED housing mounting the LED assembly and extending to a back surface of the light guide plate; And a cover bottom for receiving the light guide plate, the LED assembly, and the LED housing, wherein a plurality of holes are formed in the guide panel, the light guide plate, the LED housing, and the cover bottom in an area overlapping the bezel, A plurality of screws are inserted into the guide panel, the light guide plate, the LED housing, and the cover bottom at the same time.

Description

[0001] Liquid crystal display [0002]

Embodiments of the present invention relate to a liquid crystal display, and more particularly, to a liquid crystal display for simultaneously fixing a guide panel, a cover bottom, and a backlight unit.

2. Description of the Related Art Generally, a liquid crystal display (LCD) is a type of flat panel display that displays images using the electrical and optical characteristics of a liquid crystal having characteristics intermediate between a liquid and a solid. Thin and light, low power consumption and driving voltage are used in various applications throughout the industry.

On the other hand, the liquid crystal display device requires a separate light source because it is a non-luminescent element that emits light due to external factors.

Accordingly, a backlight unit having a light source on the back surface of the liquid crystal display panel is provided to irradiate light toward the front surface of the liquid crystal display, and the light is diffused through a plurality of optical sheets, And is realized as an image which can be identified.

Hereinafter, a structure of a conventional liquid crystal display device will be described.

1 is a cross-sectional view of a conventional liquid crystal display device.

The liquid crystal display device includes a liquid crystal display panel (not shown) and a backlight unit (not shown).

Here, the liquid crystal display panel is composed of the thin film transistor substrate 11 and the color filter substrate 13. The thin film transistor substrate 11 has a thin film transistor (not shown) connected to a pixel electrode (not shown) for each pixel. The thin film transistor switches the voltage to be transmitted to the pixel electrode, A voltage is applied to a liquid crystal layer (not shown) interposed between common electrodes (not shown) of the liquid crystal display panel to display an image on the screen display portion of the liquid crystal display panel.

The color filter substrate 13 filters light emitted from the liquid crystal layer (not shown) with various colors.

A backlight unit (not shown) is disposed on the lower surface of the liquid crystal display panel 15.

The backlight unit is composed of an LED assembly 22, a light guide plate 24, a reflective sheet 23, and an optical sheet 25.

First, the LED assembly 22 includes a printed circuit board (PCB) 22b including a light emitting diode 22a (Light Emitting Diode) and a circuit portion for driving the LED 22a And the light generated from the LED assembly 22 is directly incident on the light incidence surface formed on one side of the light guide plate 24.

The light guide plate 24 converts the light incident from the LED assembly 22 into a face light source of uniform luminance and then exits to the upper surface and the lower surface.

At this time, the reflective sheet 23 reflects the surface light source emitted to the lower surface and emits the surface light source to the upper surface of the light guide plate 24.

The surface light source is incident on the optical sheet 25 on the upper surface, and the optical sheet 25 partially condenses and diffuses (scatters) the incident surface light source and emits the light onto the upper surface.

The cover bottom 40 of the light guide plate 24 is coupled to the top cover 50. The guide panel 30 guides the lower surface of the liquid crystal display panel and the cover bottom 40, The fixing with the panel 30 is made by a side screw S which is fastened in the side direction.

At this time, the side screw S expands the non-display area of the liquid crystal display device by the length of the side screw S, so that the width of the bezel b of the top cover 50 can be increased.

The guide panel 30 is formed of a metal material to support the liquid crystal display panel. When the guide panel 30 is exposed to heat for a long time due to heat inside the liquid crystal display device, 24 so that the guiding portion is bent by the heat. However, the side screw S can not fix the guiding portion between the liquid crystal display panel of the guide panel 30 and the light guide plate 24, and thus it is difficult to prevent the warping phenomenon.

Such a bending phenomenon may provide a gap between the guide panel 30 and the optical sheet 25, and light may leak into the liquid crystal display panel, thereby causing a hot spot phenomenon.

When the liquid crystal display device is used in a large-sized product such as a TV, it is required to fix the light guide plate 24 in order to prevent the light guide plate 24 from swinging. Thereby forming a fixing pin P. 1, the fixing pin P is formed in a region of the side surface of the light guide plate 24.

Hereinafter, the position where the fixing pin P is formed will be described in more detail with reference to FIG.

2 is an exploded perspective view showing a light guide plate, a cover bottom, and an LED assembly.

As shown in the figure, a fixing groove h is formed on the edge side of the light guide plate 24. The cover bottom 40 formed on the lower surface of the light guide plate 24 is formed with a fixing pin P protruding from the upper surface at a position corresponding to the fixing groove h.

At this time, the LED assembly 22 composed of the LED 22a and the PCB 22b may be formed on opposite sides of the light guide plate 24.

Since the diameter of the hollow space in the fixing groove h and the diameter of the fixing pin P are equal and the fixing pin P surrounds the edge of the light guide plate 24, The light guide plate 24 can be fixed.

However, when the light guide plate 24 expands due to heat or moves due to the transportation of the product, the impact applied to the fixing pin P is not transmitted to the fixing pin P because the fixing pin P is fixed to only one side, The fixing pin P is bent or cracked.

In addition, a collision between the fixing pin P and the light guide plate 24 may cause cracks in the light guide plate 24 as well.

These cracks have been pointed out to be very sensitive to mechanical reliability since they can cause more cracks over time.

Therefore, in order to solve the above-described problems, the embodiments of the present invention have an object to improve the mechanical reliability by fixing the guide panel, the light guide plate, the cover bottom, and the like at the same time, and to eliminate the screen failure of the liquid crystal display device.

According to an aspect of the present invention, there is provided a liquid crystal display device including: a liquid crystal display panel including an image display unit; A top cover extending from the bezel portion and guiding a side surface of the liquid crystal display panel, the bezel portion including a bezel portion surrounding an edge of the image display portion; A guide panel which overlaps with the bezel portion of the top cover and guides a bottom edge of the liquid crystal display panel; A light guide plate disposed on the lower surface of the liquid crystal display panel so as to overlap with the guide panel; An LED assembly disposed to face one side of the light guide plate; An LED housing mounting the LED assembly and extending to a back surface of the light guide plate; And a cover bottom for receiving the light guide plate, the LED assembly, and the LED housing, wherein a plurality of holes are formed in the guide panel, the light guide plate, the LED housing, and the cover bottom in an area overlapping the bezel, A plurality of screws are inserted into the guide panel, the light guide plate, the LED housing, and the cover bottom at the same time.

Preferably, the plurality of holes formed in each of the guide panel, the light guide plate, the LED housing, and the cover bottom are formed such that the holes formed on the facing surfaces are symmetrical.

The plurality of screws include a head portion and a body portion, and the plurality of screws are inserted from the guide panel toward the cover bottom so that the head portion is disposed on the body portion.

The plurality of holes formed in the guide panel are formed such that the head part is inserted into the guide panel.

In addition, a helical groove is formed in a plurality of holes formed in the cover bottom, and a helical groove corresponding to the helical groove of the cover bottom is formed in a lower region of the body portion of the plurality of screws, And is fixed to the bottom.

The guide panel may have an inner side coupled to the cover bottom and an outer side coupled to the top cover.

The light guide plate may further include a reflective sheet having a plurality of holes formed at the same position as a plurality of holes formed in the light guide plate on the back surface of the light guide plate.

The liquid crystal display device according to at least one embodiment of the present invention configured as described above,

First, the guide panel, light guide plate, and cover bottom can be fixed at the same time.

Second, the fixing of the light guide plate is made on both the guide panel and the cover bottom, so that the durability of the screw can be improved.

Third, it is possible to prevent the guide panel from being warped, thereby eliminating defects on the screen display portion of the liquid crystal display panel and reducing the width of the bezel portion.

Fourth, since the assembly of components in the assembling process of the liquid crystal display device proceeds from the upper part to the lower part, the screw fastening method of the present invention can improve the production speed with respect to the side screws.

1 is a cross-sectional view of a conventional liquid crystal display device.
2 is an exploded perspective view showing a light guide plate, a cover bottom, and an LED assembly.
3 is an exploded perspective view of a liquid crystal display device according to an embodiment of the present invention.
4 is a sectional view of a liquid crystal display according to an embodiment of the present invention.
5 is a perspective view illustrating a structure of a screw according to an embodiment of the present invention.
6A is a plan view of an LED assembly and a light guide plate according to an embodiment of the present invention.
6B is a plan view of another light guide plate according to an embodiment of the present invention.
7 is a plan view of a liquid crystal display device according to an embodiment of the present invention.

Hereinafter, a liquid crystal display device according to an embodiment of the present invention will be described in detail with reference to the drawings.

In the present specification, similar components are denoted by the same reference numerals in different embodiments, and the description thereof is replaced with the first explanation.

As used herein, the singular forms "a", "an" and "the" include plural referents unless the context clearly dictates otherwise.

3 is an exploded perspective view of a liquid crystal display device according to an embodiment of the present invention.

3, the liquid crystal display device 110 according to one embodiment of the present invention includes a liquid crystal display panel 115 on which an image is displayed, and a liquid crystal display panel 115 that is connected to one side of the liquid crystal display panel 115 And a backlight unit 120 disposed on the back surface of the liquid crystal display panel 115 and irradiating the liquid crystal display panel 115 with light.

The edge of the liquid crystal display panel 115 is supported by the guide panel 130 and the upper surface of the liquid crystal display panel 115 is surrounded by the top cover 150. The backlight unit 120 under the liquid crystal display panel 115 is accommodated in the cover bottom 140. The cover bottom 140 is coupled to the inside of the guide panel 130 and the top cover 150 is coupled to the outside of the guide panel 130.

The liquid crystal display panel 115 plays a key role in image display. The liquid crystal display panel 115 includes a thin film transistor (TFT) substrate 111 on which a liquid crystal layer (not shown) And a substrate 113.

Although not shown in the drawing, a plurality of gate lines and data lines cross each other on the inner surface of the thin film transistor substrate 111, pixels are defined, thin film transistors are provided at each intersection, One-to-one correspondence.

On the inner surface of the color filter substrate 113, color filters of red (R), green (G), and blue (B) colors corresponding to the respective pixels and a color filter And a black matrix (black matrix) covering non-display elements such as transistors. In addition, a transparent common electrode covering these elements is provided.

A polarizing plate (not shown) for selectively transmitting only specific light is attached to the upper and lower outer surfaces of the two substrates, respectively.

The liquid crystal display panel 115 is connected to the circuit board 117 through a connection member 116 such as a flexible circuit board or a tape carrier package (TCP) along at least one edge thereof, And is brought into close contact with the side surface of the guide panel 130 or the back surface of the cover bottom 140 appropriately.

When a thin film transistor (not shown) selected for each gate line (not shown) is turned on by an on / off signal of a gate driving circuit (not shown) transferred to the liquid crystal display panel 115, (Not shown) is transmitted to the corresponding pixel electrode (not shown) through a data line (not shown), and the arrangement direction of the liquid crystal molecules changes due to an electric field between the pixel electrode and the common electrode And shows the difference in transmittance.

On the other hand, a backlight unit 120 is disposed on the back surface of the liquid crystal display panel 115. The backlight unit 120 includes an optical sheet 125 formed on the back surface of the liquid crystal display panel 115 and diffusing and condensing light, a light guide plate 124 disposed on the back surface of the optical sheet 125, An LED assembly 122 provided along at least one side of the light guide panel 124 and emitting light, and a reflective sheet 123 provided on the back surface of the light guide plate 124.

The optical sheet 125 disposed in parallel to the back surface of the liquid crystal display panel 115 includes a diffusion sheet 125a, a prism sheet 125b, and a protective sheet 125c which are sequentially stacked. The diffusion sheet 125a includes a base film (not shown) and a diffusion coating layer (not shown) formed on the entire surface of the base film. The diffusion sheet 125a diffuses light from the LED assembly 122 and supplies the light to the liquid crystal display panel 115 .

The prism sheet 125b has a triangular columnar prism with a predetermined arrangement on its upper surface, and allows light passing through the diffusion sheet 125a to proceed vertically, thereby improving the brightness.

On the prism sheet 125b, a protective sheet 125c for preventing external impact or foreign matter from entering is provided to protect the diffusion sheet 125a and the prism sheet 125b sensitive to dust and scratches.

On the other hand, a light guide plate 124 is disposed below the optical sheet 125.

The light guide plate 124 converts the light received from the LED assembly 122 of one side into a surface light source, and advances the light toward the front liquid crystal display panel.

The material of the light guide plate 124 may be any one of PMMA (polymethyl methacrylate), PET (polyethylene terephthlate), PC (poly carbonate), and PEN (polyethylene naphthalate).

The LED assembly 122 disposed on one side of the light guide plate 124 includes an LED 122a and a PCB 122b.

At this time, a plurality of the LEDs 122a are mounted on the PCB 122b at a predetermined interval, and the driving power is received from the PCB 122b. A plurality of LEDs 122a may be arranged in a plurality of layers on the PCB 122b according to the purpose.

The plurality of LEDs 122a emit light having colors of red (R), green (G), and blue (B) respectively toward a front side of the light guide plate 124, ) Can be turned on at once to realize white light by color mixing.

Although only the LED 122a is referred to as a light source of the backlight unit 120, the present invention can be applied to a case where the light source is a cold cathode fluorescent lamp (CCFL), an external electrode fluorescent lamp (EEFL) .

The PCB 122b is an electronic circuit board that prints a wiring pattern (not shown) on an insulating layer such as resin or ceramic to enable electrical connection with mounting of various electronic devices. The PCB 122b includes an epoxy-series FR4 PCB A flexible printed circuit board (FPCB), or an MCPCB.

The LED assembly 122 is mounted inside the LED housing 121, which is seated on the top surface of the cover bottom 140 with the inside of the light guide plate 124 facing the light incident side open.

At this time, the LED housing 121 may be formed in an 'a' shape. The vertical part in the 'b' shape mounts the LED assembly 122 and the horizontal part has a shape extending from the vertical part to the back surface of the light guide plate 124.

The LED housing 121 protects the LED assembly 122 and concentrates the light emitted from the LED 122a toward the light guide plate 124 to prevent light loss and diffuses heat generated from the LED assembly 122 .

A reflective sheet 123 is disposed on the back surface of the light guide plate 124. The reflective sheet 123 reflects light that is leaked in a direction opposite to the liquid crystal display panel 115 out of the light emitted from the LED 122a, (124) to reduce the loss of light.

The reflective sheet 123 may be made of PET (polyethylene terephthalate), PC (poly carbonate), or the like.

The light guide plate 124, the reflective sheet 123, the LED assembly 122 and the LED housing 121 are accommodated on the upper surface of the cover bottom 140, As shown in Fig.

The plurality of holes h1, h2, h3, h4, and h5 are disposed at the same positions in the guide panel 130, the light guide plate 124, the reflective sheet 123, the LED housing 121, and the cover bottom 140, As shown in FIG. A plurality of screws S are inserted into the plurality of holes h1, h2, h3, h4 and h5 so that the guide panel 130, the light guide plate 124, the reflection sheet 123, the LED housing 121, The cover bottom 140 can be fixed.

At this time, the plurality of holes h1 of the guide panel 130 are formed in a region of the lower surface of the liquid crystal display panel 115. The area is a region overlapping a bezel (not shown) having a certain width in the top cover 150 and framing the liquid crystal display panel 115.

The holes formed on the opposite surfaces of the plurality of holes h1 may be symmetrically formed. However, the holes may be formed only on the long sides of the guide panel 130, the light guide plate 124, the reflective sheet 123, the LED housing 121, and the cover bottom 140 in the embodiment of the present invention , The lower portion including the guide panel 130, and the cover bottom 140, can be fixed in any position.

The light guide plate 124, the reflective sheet 123, the LED housing 121, and the cover bottom 140 are provided with a plurality of holes (not shown) at the same positions where the plurality of holes h1 of the guide panel 130 are formed. h2, h3, h4, and h5 may be formed.

At this time, the screw S is inserted in the direction of the cover bottom 140 from the upper part of the guide panel 130. The head S may be inserted into the guide panel 130 and the body S may be inserted into the guide panel 130, The light guide plate 124, the reflection sheet 123, the LED housing 121, and the cover bottom 140 all having the same thickness.

Accordingly, the screw S can fix the guide panel 130, the light guide plate 124, the reflection sheet 123, the LED housing 121, and the cover bottom 140 at the same time.

Hereinafter, the manner in which the screw S fixes a part of the liquid crystal display device through the sectional view of the liquid crystal display device will be described in more detail.

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

In the following description, reference numerals are used in the drawings, and the components not illustrated in the drawings are denoted by the same reference numerals in FIG.

 In FIG. 4, the screw S is inserted at a position overlapping the bezel b of the top cover 150. Therefore, the insertion position of the screw S is determined by the area extending from the guide panel 130 to the lower surface of the liquid crystal display panel 115 to support the liquid crystal display panel 115 and the light guide plate 124 and the reflective sheet 123 and an area corresponding to the bezel in the LED housing 121 and the cover bottom 140. [

At this time, the screw S is composed of the head part 250 and the body part 200, which will be described in detail with reference to FIG. 5 is a perspective view illustrating a structure of a screw according to an embodiment of the present invention.

5, an upper part of the head part 250 of the screw S is formed with a cross-shaped groove, and a screwdriver can be inserted from the upper part to the lower part by inserting a device such as a screwdriver into the groove, do.

The body portion 200 of the screw S has a smaller diameter than the diameter of the head portion 250 and extends downward.

At this time, the spiral groove 205 in the body 200 may be formed only below the body 200. Here, the spiral groove (not shown) in the hole corresponding to the spiral groove 205 may be formed in a hole formed in at least one of the structures disposed on the lower part of the liquid crystal display device such as the cover bottom or the LED housing. Therefore, the body portion of the screw S is fastened to a structure disposed below the cover bottom or the like.

However, the embodiment of the present invention is not limited to this, and includes the case where the helical groove 205 is formed on another part and the whole body part 200. [

Here, the arrangement of the LEDs facing the light incidence surface when the screw S is inserted near the light incidence surface when the screw S is inserted into the light guide plate will be examined.

6A is a plan view of an LED assembly and a light guide plate according to an embodiment of the present invention.

 A plurality of holes h2 may be formed in the light guide plate 124 as shown in FIG. The plurality of holes h2 may be formed symmetrically with respect to each other.

Here, one side of the light guide plate 124 facing the area where the LED 122a assembly is disposed is a light incidence surface. It is shown in the drawing that a hole h2 through which one screw can be inserted is formed near the light incidence surface.

At this time, the screw is disposed in a path along which light travels, and the screw is made of a metal material, so that light can not be transmitted. Therefore, the LEDs 122a are arranged on the PCB 122b so that the areas corresponding to the areas where the screws are disposed are further apart from the other areas.

Therefore, when a plurality of screws are inserted in the vicinity of the light incidence surface, the number of areas where the LEDs 122a are spaced apart from each other in the area corresponding to the arrangement position of the screws can be increased by the number of screws.

Therefore, the luminance value for power consumption can be increased by such arrangement.

Meanwhile, the hole formed in the light guide plate is formed for inserting a screw for the purpose of fixing the light guide plate, so that the space through which the screw is inserted in the light guide plate may be a groove shape instead of a hole. 6B is a plan view of another light guide plate according to an embodiment of the present invention.

The groove h6 in FIG. 6B may be formed at the same position as the hole in FIG. 6A. The groove h6 may have a width equal to the diameter of the screw and may have a shape of being punched into the inside of the light guide plate 124. [ Or the width of the groove h6 may be formed to be slightly wider than the diameter of the screw so as to prevent the light guide plate 124 from being collided with the screw due to heat expansion.

4, the upper surface of the head portion 250 of the screw S may be formed to be flat so as to have the same plane as the upper surface of the guide panel 130. As shown in FIG. Accordingly, the plurality of holes formed in the guide panel 130 are formed with a step to insert the body 200 into the guide panel 130.

The lower surface of the body portion 200 may be flat so as to have the same plane as the lower surface of the cover bottom 140.

The screw S is not formed in the upper surface of the guide panel 130 and the lower surface of the cover bottom 140 so that the slimness of the liquid crystal display device can be achieved and the area for other arrangements can be widened .

In an embodiment of the present invention, the body 200 of the screw S is engaged and fixed with a spiral groove formed in the cover bottom 140, and the head 250 is inserted into a plurality of holes So that the guide panel 130 can not be bent upward.

Accordingly, the screw S can be fixed to prevent the guide panel 130 from being deformed even when heat is applied thereto. In this case, since the guide panel 130 is bent, hot spot phenomenon and loss of light caused when light leaks from the light-incident portion of the light guide plate 124 to the liquid crystal display panel can be improved.

In addition, since the light guide plate 124 is fixed on both the upper and lower surfaces of the light guide plate 124, when the light guide plate 124 and the screw S collide with each other, It is possible to improve the durability of the light guide plate fixing means by preventing the screw S from being bent or bent.

In addition, one embodiment of the present invention improves the prior art from a top screw to a bottom screw by inserting a side screw into the bottom screw, The space occupied by the top cover can be removed, thereby narrowing the width of the bezel of the top cover.

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

 In the figure, the top cover 150 surrounds the liquid crystal display panel. Here, the upper surface of the top cover 150 has a predetermined width, and a portion surrounding the image display unit 119 is a bezel b.

Here, the position where the screw S is inserted may be inserted into the edge of the light guide plate 124 indicated by a dotted line in the drawing as a lower surface of the bezel b. That is, since the bezel b and the light guide plate 124 partially overlap the edge of the light guide plate 124, the screw S can be inserted into the overlapping area.

At this time, the region where the screw S is inserted is a non-image display portion (not shown) which does not affect the brightness of the image display portion which was also present in the prior art. Therefore, the screw S according to the embodiment of the present invention can reduce the width of the bezel b by removing the space occupied by the side screw of the prior art under the bezel b and inserting it into the non-image display portion .

According to an embodiment of the present invention, since the assembling process of the liquid crystal display device proceeds by assembling the components from the top to the bottom, the screws according to the embodiment of the present invention are inserted from the upper side to the lower side The production speed can be further improved.

In the liquid crystal display according to the prior art of FIG. 1, the side screw for fixing the cover bottom and the guide panel and the fixing pin for fixing the light guide plate are all provided only by a single screw in the embodiment of the present invention, An embodiment of the present invention can also bring about an effect of cost reduction.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Therefore, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention defined in the following claims are also within the scope of the present invention.

115: liquid crystal display panel 120: backlight unit
121: LED housing 122: LED assembly
123: reflective sheet 124: light guide plate
125: optical sheet 130: cover bottom
140: Guide panel 150: Top cover
b: Bezel part S: Screw

Claims (7)

A liquid crystal display panel including an image display unit;
A top cover extending from the bezel portion and guiding a side surface of the liquid crystal display panel, the bezel portion including a bezel portion surrounding an edge of the image display portion;
A guide panel which overlaps the bezel portion of the top cover and has a vertical portion arranged to intersect with the liquid crystal display panel and a horizontal portion extending inward from the vertical portion and guiding a lower edge of the liquid crystal display panel;
A light guide plate disposed on the lower surface of the liquid crystal display panel so as to overlap with the guide panel;
An LED assembly disposed to face one side of the light guide plate;
An LED housing mounting the LED assembly and extending to a back surface of the light guide plate; And
And a cover bottom for receiving the light guide plate, the LED assembly, and the LED housing,
A plurality of holes are formed in a region of the guide panel that overlaps with the bezel in a horizontal portion of the guide panel, a light guide plate, an LED housing, and a cover bottom, and a plurality of screws are inserted into the plurality of holes, The LED housing and the cover bottom are simultaneously fixed so that the horizontal portion of the guide panel is prevented from being bent,
Wherein the plurality of screws include a head portion and a body portion, the plurality of screws being inserted from the horizontal portion of the guide panel toward the cover bottom so that the head portion is disposed on the body portion,
Wherein the plurality of holes formed in the guide panel are formed such that the head portion is inserted into the guide panel and the upper surface of the head portion is disposed on the same plane as the upper surface of the horizontal portion of the guide panel. . The method according to claim 1,
Wherein a plurality of holes formed in each of the guide panel, the light guide plate, the LED housing, and the cover bottom are symmetric with the holes formed on the facing surface. delete delete The method according to claim 1,
A spiral groove is formed in a plurality of hole inner surfaces formed in the cover bottom,
Wherein a screw groove corresponding to a screw groove of the cover bottom is formed in a lower region of the body portion of the plurality of screws so that a body portion of the screws is fastened to the cover bottom. The method according to claim 1,
Wherein the guide panel has an inner side coupled to the cover bottom and an outer side coupled to the top cover. The method according to claim 1,
Further comprising a reflective sheet having a plurality of holes formed at the same position as a plurality of holes formed in the light guide plate on the back surface of the light guide plate.

Images