KR20120026675A - Liquid crystal display device - Google Patents

Abstract

PURPOSE: A liquid crystal display device is provided to realize high brightness and prevent damage due to thermal deformation of a light guide plate. CONSTITUTION: A light guide plate(123) is mounted on a reflection plate. An LED assembly(129) is attached along with a light incident surface of the light guide plate. A plurality of optical sheets are mounted on the top of the light guide plate. A liquid crystal panel is mounted on the top of the optical sheets. A cover bottom(150) is combined with a support main. A boss protrudes from a horizontal surface of the cover bottom.

Description

Liquid crystal display device

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device capable of preventing flow of a light guide plate and preventing damage caused by thermal deformation of the light guide plate.

Liquid crystal display devices (LCDs), which are used for TVs and monitors due to their high contrast ratio and are advantageous for displaying moving images, are characterized by optical anisotropy and polarization of liquid crystals. The principle of image implementation by

Such a liquid crystal display is an essential component of a liquid crystal panel bonded through a liquid crystal layer between two side-by-side substrates, and realizes a difference in transmittance by changing an arrangement direction of liquid crystal molecules with an electric field in the liquid crystal panel. do.

On the other hand, the liquid crystal panel requires a separate light source to display the difference in transmittance as an image because it does not have a self-luminous element, and for this purpose, a backlight including a light source is disposed on the back of the liquid crystal panel.

The general backlight unit is classified into an edge type and a direct type according to the arrangement of the lamps. The edge type has a structure in which one or a pair of lamps are disposed at one side of the light guide plate, or two or Two pairs of lamps have a structure arranged on each side of the light guide plate, and the direct type has a structure in which several lamps are arranged under the optical sheet.

Here, the edge type is easier to manufacture than the direct type, and has the advantage of being lighter in weight and lower power consumption than the direct type.

1 is a cross-sectional view of an LCD including an edge type backlight unit.

As illustrated, a general edge type liquid crystal display device includes a liquid crystal panel 10, a backlight unit 20, a support main 30, a cover bottom 50, and a top cover 40.

The liquid crystal panel 10 is a part that plays a key role in image expression and is composed of first and second substrates 12 and 14 bonded to each other with a liquid crystal layer interposed therebetween.

The backlight unit 20 is provided behind the liquid crystal panel 10.

The backlight unit 20 has a plurality of LEDs 29a coplanar with the LED assembly 29 and the LED assembly 29 mounted at a predetermined interval on the PCB 29b and mounted on the reflector 25. The light incident surface includes a light guide plate 23 facing the LED assembly 29 and an optical sheet 21 seated on the light guide plate 23.

The optical sheet 21 on the light guide plate 23 includes a diffusion sheet and at least one light collecting sheet.

The liquid crystal panel 10 and the backlight unit 20 have a top cover 40 surrounding the top edge of the liquid crystal panel 10 and a back surface of the backlight unit 20 in a state where the edges are surrounded by the support main 30 having a rectangular frame shape. Cover cover 50 to cover each is coupled in front and rear are integrated through the support main 30 as a medium.

On the other hand, in order to implement a higher brightness liquid crystal display device, the LED 29a is attached to the light incident surface of the light guide plate 23 to secure insufficient luminance and uniformity, but in this case, it is generated from the LED 29a. Due to the high temperature heat, the light guide plate 23 is thermally deformed and damage occurs.

The present invention has been made to solve the above problems, and a first object of the present invention is to provide a high brightness liquid crystal display and to prevent damage caused by thermal deformation of the light guide plate.

For this reason, the second object is to improve the brightness and the image quality of the liquid crystal display.

In order to achieve the object as described above, the present invention and the main frame of the rectangular frame; A reflection plate located inside the support main; A light guide plate mounted on the reflection plate and having guide grooves formed at both sides of the light incident surface and the edges perpendicular to the light incident surface; An LED assembly attached along the light incident surface of the light guide plate; A plurality of optical sheets seated on the light guide plate; A liquid crystal panel seated on the plurality of optical sheets; A cover bottom coupled to the support main and having a horizontal surface and a boss protruding from the horizontal surface corresponding to the guide groove; A top cover that covers an upper edge of the liquid crystal panel and is coupled to the support main and the cover bottom, and guide grooves formed at both edges are closer to the light incident surface than the light incident surface opposite to the light incident surface. By positioning the light guide plate to provide a liquid crystal display device to expand and contract through the side of the incoming light incident surface in accordance with the rise in temperature due to the LED assembly.

In this case, the guide grooves formed on both side edge surfaces are formed in a region closest to the light incident surface among regions where the two edges are equally divided into three equal widths, and the guide grooves formed on the light incident surface are in the longitudinal direction of the light incident surface. It is formed at a position of 1/2 of the, the guide groove is provided in a form concaved toward the light incident surface from the light incident surface.

The guide groove formed on the light incident surface is formed to have a first width and a first depth from the light incident surface toward the light incident surface, and the guide grooves formed at both edges are provided in a concave direction in a direction facing each other. Guide grooves formed at both edges are formed to have a second depth in a direction facing each other with a second width.

In addition, the boss is made of the same diameter as the first width and the second width, the diameter is smaller than the first depth and the second depth, the boss is selected from cylinder, polygonal column, triangular column It takes one form.

Here, the guide groove is made of a shape selected from a semi-circular, polygonal, V-cut (V-Cut) type.

As described above, according to the present invention, by forming a plurality of guide grooves on the edge surface of the light guide plate and forming a boss in the cover bottom corresponding to the guide groove, the light guide plate is fixed in the modular liquid crystal display device. The light guide plate is prevented from flowing in the horizontal or vertical direction by external impact or shaking in a state where the light guide plate is accommodated in the cover bottom.

Through this, the LED is not damaged due to the flow of the light guide plate, and the optical characteristic of the liquid crystal display is changed, thereby preventing the problem of deterioration in image quality.

Particularly, in the present invention, the guide grooves formed at both edges of the light guide plate are positioned close to the light incident surface of the light guide plate, thereby allowing the light guide plate to freely contract and expand to the light incident surface side of the light guide plate by the high temperature heat generated from the LED. There is an effect that can prevent the damage caused by thermal deformation of the.

1 is a cross-sectional view of an LCD including an edge type backlight unit.
2 is an exploded perspective view of a liquid crystal display according to an exemplary embodiment of the present invention.
3A to 3B schematically illustrate that the light guide plate is prevented from flowing by the cover bottom according to the embodiment of the present invention.
4A is a plan view schematically illustrating a light guide plate seated on a cover bottom;
4B-4C are enlarged plan views of a portion of FIG. 4A.
5a to 5d and 6a to 6f are photographs showing vibration and impact test results of the liquid crystal display according to the exemplary embodiment of the present invention.
7a to 7b are photographs showing the high temperature and high humidity test results of the liquid crystal display of the present invention.

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

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

As shown, the liquid crystal display device includes a liquid crystal panel 110, a backlight unit 120, a support main 130, a cover bottom 150, and a top cover 140.

First, the liquid crystal panel 110 plays a key role in image expression, and includes the first and second substrates 112 and 114 bonded to each other with the liquid crystal layer interposed therebetween.

At this time, although not clearly shown in the drawings under the premise of an active matrix method, a plurality of gate lines and data lines intersect on the inner surface of the first substrate 112, which is commonly referred to as a lower substrate or an array substrate, thereby defining pixels. In addition, a thin film transistor (TFT) is provided at each crossing point and is connected one-to-one with a transparent pixel electrode formed in each pixel.

An inner surface of the second substrate 114, called an upper substrate or a color filter substrate, may correspond to each pixel, for example, a color filter of red (R), green (G), and blue (B) color, and these. A black matrix is provided around each other to cover non-display elements such as gate lines, data lines, and thin film transistors. In addition, a transparent common electrode covering them is provided.

Along the at least one edge of the liquid crystal panel 110, the gate and the data printed circuit board 117 are connected to each other via a connecting member 116 such as a flexible printed circuit board. It is flipped to the back surface of 150, and is in close contact.

Although not clearly shown in the drawings, an alignment layer for determining the initial molecular alignment direction of the liquid crystal is interposed between the two substrates 112 and 114 of the liquid crystal panel 110 and the liquid crystal layer, and the liquid crystal layer filled therebetween. A seal pattern is formed along the edges of both substrates 112 and 114 to prevent leakage.

In this case, polarizers (not shown) are attached to outer surfaces of the first and second substrates 112 and 114, respectively.

A backlight unit 120 for supplying light is provided on a rear surface of the liquid crystal panel 110 such that a difference in transmittance of the liquid crystal panel 110 is expressed to the outside.

The backlight unit 120 includes an LED assembly 129 arranged along at least one edge length direction of the support main 130, a white or silver reflector 125, and a light guide plate 123 mounted on the reflector 125. And a plurality of optical sheets 121 interposed thereon.

The above-described LED assembly 129 is a light source of the backlight unit 120, is located on one side of the light guide plate 123 to face the light incident surface of the light guide plate 123, the LED assembly 129 is a plurality of LED (129a) And, its LEDs (129a) includes a PCB (129b) that is mounted at a predetermined interval apart.

At this time, the LED assembly 129 of the present invention is attached to one light incident surface of the light guide plate 123, so that the light supplied to the light incident surface of the light guide plate 123 is uniformly emitted to the front of the light guide plate 123.

At this time, the light incident surface of the LED assembly 129 and the light guide plate 123 is attached with a transparent adhesive resin (not shown).

The plurality of LEDs 129a emits light having red (R), green (G), and blue (B) colors toward the light incident surface of the light guide plate 123, respectively, and the plurality of RGB LEDs (129a). By lighting all at once, white light by color mixing can be realized.

On the other hand, by using the LED (129a) configured with an LED chip (not shown) that emits all the colors of RGB, each of the LEDs (129a) may be implemented to implement white light, or including a chip that emits white The emitting LED 129a may be used.

In addition, a plurality of LEDs 129a emitting RGB light may be bundled and mounted in a cluster, and a plurality of LEDs 129a mounted on the FPCB 129b are arranged on the FPCB 129b. It is also possible to arrange them side by side or to arrange them side by side in a plurality of columns.

On the other hand, the LED 129a is a light emitting device, the temperature is rapidly increased according to the use time, the temperature rise has a feature that is accompanied by a change in the lifetime and brightness of the LED (129a). Therefore, one of the most important matters when the LED 129a is used as a light source of the backlight unit 120 is a heat dissipation design according to the temperature rise of the LED 129a.

Thus, the backlight unit 120 of the present invention is further provided with an LED heat sink 128, the LED heat sink 128 is formed of a cross-section bent in the form of "b", made of a metal material excellent in thermal conductivity.

Therefore, the high temperature heat generated from the plurality of LEDs 129a is transferred to the LED heat sink 128, which is quickly and efficiently released to the outside. As a result, the liquid crystal display of the present invention minimizes the temperature rise due to the use of the LED 129a.

Accordingly, the liquid crystal display of the present invention has a heat dissipation design of the efficient LED assembly 129 by the LED heat sink 128.

The light guide plate 123 evenly spreads the light incident from the LED 129a to a wide area of the light guide plate 123 while propagating through the light guide plate 123 by several total reflections to provide a surface light source to the liquid crystal panel 110.

The light guide plate 123 may include a pattern of a specific shape on the rear surface to supply a uniform surface light source.

Here, the pattern may be configured in various ways, such as an elliptical pattern, a polygon pattern, a hologram pattern, and the like to guide the light incident into the light guide plate 123. The pattern is formed on the lower surface of the light guide plate 123 by a printing method or an injection method.

In particular, the light guide plate 123 of the present invention is characterized in that a plurality of guide grooves 200 are formed at the light incident surface to which the LED assembly 129 is attached and at both edges perpendicular to the light incident surface.

That is, the light guide plate 123 of the present invention is fixed in the modular liquid crystal display device through the guide groove 200, so that the light guide plate 123 is externally impacted or shaken when the light guide plate 123 is accommodated in the cover bottom 150. As a result, the light guide plate 123 is prevented from flowing in the horizontal or vertical direction.

Through this, the plurality of LEDs 129a may be prevented from being damaged by the flow of the light guide plate 123, and the optical characteristics of the liquid crystal display may be changed to prevent the problem of deterioration in image quality.

In particular, the plurality of guide grooves 200 formed at both edges perpendicular to the light incident surface are located close to the light incident surface to which the LED assembly 129 is attached, and do not have a separate guide groove on the light incident surface opposite to the light incident surface. do.

That is, the light guide plate 123 does not have a separate fixing structure when the position of the light guide plate 123 is fixed in the liquid crystal display device modularized through the guide groove 200.

Therefore, even if the light guide plate 123 is expanded and contracted by heat generated from the LED 129a, the light guide plate 123 can freely contract and expand through the side of the incoming light incident surface which is not provided with a separate fixing structure. It is possible to prevent damage caused by thermal deformation of the light guide plate 123.

We will discuss this in more detail later.

The reflective plate 125 is positioned on the rear surface of the light guide plate 123, and reflects light passing through the rear surface of the light guide plate 123 toward the liquid crystal panel 110 to improve the brightness of the light.

The plurality of optical sheets 121 on the light guide plate 123 include a diffusion sheet and at least one light collecting sheet, and diffuse or condense the light passing through the light guide plate 123 to provide a more uniform surface to the liquid crystal panel 110. Allow the light source to enter.

The liquid crystal panel 110 and the backlight unit 120 are modularized through the top cover 140, the support main 130, and the cover bottom 150. The top cover 140 is formed by the top edge of the liquid crystal panel 110 and the top cover 140. Configure to cover the side.

Here, the top cover 140 is a rectangular frame having a cross section bent in a “b” shape to cover the top and side edges of the liquid crystal panel 110, and opens the front of the top cover 140 to open the liquid crystal panel 110. Configure to display the image implemented in the.

In addition, the cover bottom 150 on which the liquid crystal panel 110 and the backlight unit 120 are seated and is the basis for assembling the entire apparatus of the liquid crystal display device has a rectangular plate shape having an edge portion of which the edge is vertically bent. 120) the horizontal surface 151 in close contact with the rear surface and the edge thereof is composed of an edge portion 153 vertically bent upwardly.

At this time, the boss 155 inserted into the guide groove 200 of the light guide plate 123 is formed on the horizontal surface 151 of the cover bottom 150 corresponding to the guide groove 200 of the light guide plate 123. . Therefore, the light guide plate 123 is fixed as the boss 155 of the cover bottom 150 is inserted into the guide groove 200 of the light guide plate 123.

A support main 130 having a rectangular frame shape seated on the cover bottom 150 and covering the edges of the liquid crystal panel 110 and the backlight unit 120 is combined with the top cover 140 and the cover bottom 150 to form a liquid crystal. The display device 100 is completed.

In this case, the top cover 140 may also be referred to as a case top or a top case, and the support main 130 may also be referred to as a guide panel, a main support, or a mold frame, and the cover bottom 150 may be referred to as a bottom cover or a lower cover. It is also built.

The liquid crystal display described above can prevent the flow of the light guide plate 123 even when an external impact or shake occurs, so that the LED 129a of the LED assembly 129 is damaged by the flow of the light guide plate 123. In addition, the optical characteristics of the liquid crystal display may be changed to prevent a problem of deterioration of image quality.

In particular, the present invention is the guide groove 200 and the boss 155 of the cover bottom 150 is provided to prevent the flow of the light guide plate 123 and the light incident surface of the light guide plate 123 to which the LED assembly 129 is attached; Since the light guide plate 123 does not have a separate fixing structure on the light-receiving surface of the light guide plate 123, the light guide plate 123 may be expanded or contracted by heat generated from the LED 129a. It can be freely shrunk and expanded through the side of the incoming light incident surface which is not provided with a separate fixing structure.

Accordingly, it is possible to prevent damage caused by thermal deformation of the light guide plate 123.

3A to 3B schematically illustrate that the light guide plate is prevented from flowing by the cover bottom according to the embodiment of the present invention.

As shown, the cover bottom 150 has a rectangular plate shape having an edge portion of which the edge is vertically bent, and a horizontal plane 151 closely contacting the rear surface of the backlight unit (120 of FIG. 2) and its edges are vertically bent upwardly. The edge portion 153 is formed.

At this time, the boss for preventing the light guide plate 123 from flowing in the first edge portion 153a and the second and third edge portions 153c and 153d perpendicular to the first edge portion 153a of the cover bottom 150. 155 is formed.

The boss 155 protrudes from the horizontal surface 151 of the cover bottom 150 toward the light guide plate 123.

The reflection plate 125 is mounted on the horizontal surface 151 of the cover bottom 150, and the light guide plate 123 is seated on the reflection plate 125, and the LED assembly 129 is disposed on the light incident surface 123a of the light guide plate 123. ) Is attached and fixed, and the guide groove 200 is formed at the light receiving surface 123a and the side edges 123c and 123d perpendicular to the light receiving surface 123a to which the LED assembly 129 is attached. Thus, the light guide plate 123 is fixed to the position on the cover bottom 150.

Looking at this in more detail, the light guide plate 123 is a plastic material such as polymethylmethacrylate (PMMA) or polycarbonate (PC), which is an acrylic transparent resin, which is one of transparent materials capable of transmitting light. It is manufactured in flat type by series.

Here, PMMA is an acrylic resin, which is excellent in transparency, weather resistance and colorability, and induces light diffusion when light is transmitted.

The light guide plate 123 connects the light incident surface 123a to which the LED assembly 129 is attached, the light incident surface 123b on the opposite side thereof, and the light incident surface 123a and the light incident surface 123b and emits light. The lower surface 123f facing the surface 123e and the reflecting plate 125 and both edge surfaces 123c and 123d facing each other.

In this case, a plurality of guide grooves 200 are formed in the light receiving surface 123a and the edge surfaces 123c and 123d perpendicular to the light receiving surface 123a of the light guide plate 123, and the guide groove 200 is the light guide plate 123. It is formed by concave concave with a predetermined width and depth from the light incident surface 123a and the both side edge surfaces (123c, 123d).

That is, the guide groove 200 is formed to surround the outer surface of the boss 155 provided in the cover bottom 150, the shape of which may be variously formed corresponding to the shape of the boss 155.

The plurality of guide grooves 200 formed on the light incident surface 123a and the side edge surfaces 123c and 123d of the light guide plate 123 are formed to correspond to the bosses 155 provided in the cover bottom 150, respectively. When the 123 is seated on the cover bottom 150, the bosses 155 of the cover bottom 150 are respectively inserted into the guide grooves 200 of the light guide plate 123.

Therefore, even when an external shock or shake occurs, the light guide plate 123 is prevented from flowing by the boss 155. As a result, the LED 129a may not be damaged due to the flow of the light guide plate 123, and the optical characteristics of the liquid crystal display may be changed, thereby preventing the problem of deterioration in image quality.

At this time, the height of the boss 155 of the cover bottom 150 to have a height higher than the height of the light guide plate 123, and a plurality of optical sheets (121 of FIG. 2) interposed on the upper portion of the light guide plate 123 is also By having a guide groove (not shown) or a hole (not shown) corresponding to the boss 155, a plurality of optical sheets (121 of FIG. 2) interposed on the light guide plate 123 through the boss 155. Flow can also be prevented.

Through this, a separate configuration for fixing the position of the plurality of optical sheets (121 of FIG. 2) may be deleted.

In particular, when the light guide plate 123 of the present invention is expanded and contracted by high temperature heat generated from a plurality of LEDs 129a attached to the light incident surface 123a of the light guide plate 123, the light guide plate 123 is a light incident surface. It is possible to freely expand and contract through the 123b side.

Accordingly, it is possible to prevent damage caused by thermal deformation of the light guide plate 123.

4A is a plan view schematically illustrating a light guide plate seated on a cover bottom, and FIGS. 4B to 4C are enlarged plan views of a portion of FIG. 4A.

As shown, the boss 155 is formed on the cover bottom 150 to correspond to the guide groove 200 of the light guide plate 123, and the boss 155 is disposed on the light guide plate 123 seated on the inner surface of the cover bottom 150. In response to the guide groove 200 is formed, the boss 155 is inserted into the guide groove 200, respectively.

At this time, the center of the first guide groove 200a formed on the light receiving surface 123a of the light guide plate 123 is formed at a position approximately 1/2 of the length direction of the light receiving surface 123a of the light guide plate 123. The first boss 155a formed at the first edge portion 153a of the cover bottom 150 corresponding to the light incident surface 123a of 123 is fitted into the first guide groove 200a.

At this time, the first guide groove (200a) is provided in the form of a recessed groove having a predetermined width (w1) and depth (h1), the depth (h1) of the first guide groove (200a) is a light incident surface (123a) It is formed in the Y-axis direction defined in the figure in the form concave toward the light incident surface 123b from the side.

In this case, the diameter w2 of the first boss 155a inserted into the first guide groove 200a is preferably equal to the width w1 of the first guide groove 200a.

In addition, the diameter w2 of the first boss 155a may be smaller than the depth h1 of the first guide groove 200a.

Therefore, the first boss 155a prevents the left and right flow of the light guide plate 123, that is, the flow of the light guide plate 123 in the X-axis direction.

In addition, when the light guide plate 123 expands up and down in the Y-axis direction defined in the drawing due to the high temperature heat generated from the LED 129a, the length is increased up and down based on the first boss 155a. It is possible to prevent the damage caused by the up and down expansion of the 123.

The second and third guide grooves 200b and 200c formed at both edges 123c and 123d of the light guide plate 123 are provided in the form of grooves recessed with a predetermined width w1 and a depth h1. The depths of the second and third guide grooves 200b and 200c are recessed in a direction facing each other, and are formed in the X-axis direction defined in the drawing.

In addition, the second and third bosses 155b and 155c formed on the second and third edge portions 153c and 153d of the cover bottom 150 corresponding to both side edge surfaces 123c and 123d of the light guide plate 123 are formed. It is fitted into the second and third guide grooves (200b, 200c), respectively.

At this time, the diameters w2 of the second and third bosses 155b and 155c inserted into the second and third guide grooves 200b and 200c are respectively the widths of the second and third guide grooves 200b and 200c. It is provided in the same manner as w1, and the diameters w2 of the second and third bosses 155b and 155c are preferably smaller than the depth h1 of the second and third guide grooves 200b and 200c, respectively. Do.

Accordingly, the second and third bosses 155b and 155c prevent the up and down flow of the light guide plate 123, that is, the flow of the light guide plate 123 in the Y-axis direction, and the light guide plate is prevented by the high temperature heat generated from the LED 129a. When 123 expands from side to side, since the length increases from side to side based on the second and third bosses 155b and 155c, damage caused by the left and right expansion of the light guide plate 123 can be prevented.

In particular, the second and third guide grooves 200b and 200c formed at both edges 123c and 123d of the light guide plate 123 are formed to be located close to the light incident surface 123a of the light guide plate 123. When the edge surfaces 123c and 123d are divided into three equal parts and divided into first to third regions, the second and third guide grooves 200b and 200c are formed in the first region close to the light incident surface 123a. do.

Therefore, the light guide plate 123 may expand freely on the light incident surface 123b side.

That is, in the process of expanding and contracting the light guide plate 123 when high temperature heat is generated from the LED 129a, the light guide plate 123 is formed in the light guide surface 123a and the guide grooves 200a formed at both edge surfaces 123c and 123d. , 200b and 200c to allow the contraction and expansion to some extent, but when the contraction and expansion of the light guide plate 123 further occur, the light guide plate 123 may contract and expand through the light incident surface 123b. will be.

Therefore, damage can be prevented from occurring due to expansion and contraction of the light guide plate 123.

At this time, the positions of the guide grooves 200b and 200c formed on both side edge surfaces 123c and 123d of the light guide plate 123 are closer to the light incident surface 123a of the light guide plate 123, and thus the shrinkage and expansion of the light guide plate 123 are reduced. Since the configuration of the guide grooves 200b and 200c is too close to the light incident surface 123a of the light guide plate 123, the flow of the light guide plate 123 may occur.

Therefore, the guide grooves 200b and 200c should be formed at the proper positions of both side edge surfaces 123c and 123d of the light guide plate 123.

That is, when the light guide plate 123 contracts and expands due to heat, the stress value applied to the boss 155 and the maximum stress value generated between the boss 155 and the light guide plate 123 during impact analysis have the same value. It is preferable to form guide grooves 200b and 200c at positions.

5a to 5d and 6a to 6f are photographs showing vibration and impact test results of the liquid crystal display according to the exemplary embodiment of the present invention.

5A to 5D are results of vibration experiments of the liquid crystal display according to the exemplary embodiment of the present invention, and FIG. 5A shows the liquid crystal display of the initial state, and FIG. 5B shows the X axis of the liquid crystal display vertically. 5C is an experimental result of performing a vibration test after setting the Y-axis edge of the liquid crystal display device vertically, and FIG. 5D illustrates a vibration test after placing the liquid crystal display device horizontally. Experimental results.

5A to 5D, the guide grooves are formed on the light incidence surface and both edges of the light guide plate according to the embodiment of the present invention, and the guide grooves formed on both edges are positioned close to the light incidence surface, so that the boss formed on the cover bottom is formed. It can be confirmed that the light guide plate is not twisted even when the vibration test is performed by inserting the guide groove into each guide groove so that the light guide plate is fixed in the modular liquid crystal display device.

6A to 6F are the results of the impact test of the liquid crystal display according to the exemplary embodiment of the present invention, and FIGS. 6A and 6B show the vertical and vertical edges of the X-axis of the liquid crystal display, and then apply an impact to the upper and lower sides. 6C and 6D show an experimental result of performing an impact test by applying a shock to an upper side and a lower side after vertically setting the Y-axis edge of the LCD, and FIGS. 6E and 6F show the liquid crystal display. The test results were conducted by placing the device horizontally and applying an impact to the upper side and the lower side.

6A to 6F, guide grooves are formed on the light incident surface and both edges of the light guide plate according to the embodiment of the present invention, and the guide grooves formed on both edges are positioned close to the light incident surface, thereby forming a boss formed on the cover bottom. By inserting into each guide groove, the light guide plate is fixed in the modular liquid crystal display device so that the twist and flow of the light guide plate does not occur even when the impact test is performed.

7a to 7b are photographs showing the high temperature and high humidity test results of the liquid crystal display of the present invention.

FIG. 7A illustrates guide grooves formed on the light incident surface and both edges of the light guide plate according to the exemplary embodiment of the present invention, and the guide grooves formed at both edges are positioned close to the light incident surface, such that a boss formed on the cover bottom is fitted into each guide groove. It is a state before the experiment of the liquid crystal display device to be inserted, the position of the light guide plate is fixed in the modular liquid crystal display device, Figure 7b is a state after the high temperature and high humidity experiment of the liquid crystal display device of FIG.

At this time, the high temperature and high humidity experiment was performed for 96 hours in an atmosphere of 50 ℃.

7A to 7B, it can be seen that the liquid crystal display according to the exemplary embodiment of the present invention does not cause warpage of the light guide plate even after a high temperature and high humidity test.

This is because it is possible to freely expand and contract the light guide plate toward the light incident plate side of the light guide plate, thereby preventing damage caused by thermal deformation of the light guide plate.

As described above, the liquid crystal display of the present invention forms a plurality of guide grooves on the edge surface of the light guide plate, and forms a boss in the cover bottom corresponding to the guide groove, whereby the light guide plate is positioned within the modular liquid crystal display device. The light guide plate is fixed to prevent the light guide plate from flowing in the horizontal or vertical direction by external impact or shaking while the light guide plate is accommodated in the cover bottom.

As a result, the LED may not be damaged due to the flow of the light guide plate, and the optical characteristics of the liquid crystal display may be changed to prevent the problem of deterioration in image quality.

In particular, the guide grooves formed at both edges of the light guide plate are positioned close to the light incident surface of the light guide plate, so that the light guide plate can freely contract and expand to the light incident surface side of the light guide plate by the high temperature heat generated from the LED, thereby causing thermal deformation of the light guide plate. It is possible to prevent the damage caused by.

The present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the present invention.

123: light guide plate
(123a: light incident surface, 123b: incoming light surface, 123c, 123d: both edges, 123e: top surface, 123f: bottom surface)
129: LED assembly (129a: LED, 129b: PCB)
150: Cover Bottom
(151: horizontal plane, 153a, 153b, 153c, 153d: first to fourth edge portions)
155a, 155b, 155c: first to third bosses
200a, 200b, 200c: first to third guide grooves

Claims (8)

A support frame having a rectangular frame shape;
A reflection plate located inside the support main;
A light guide plate mounted on the reflection plate and having guide grooves formed at both sides of the light incident surface and the edges perpendicular to the light incident surface;
An LED assembly attached along the light incident surface of the light guide plate;
A plurality of optical sheets seated on the light guide plate;
A liquid crystal panel seated on the plurality of optical sheets;
A cover bottom coupled to the support main and having a horizontal surface and a boss protruding from the horizontal surface corresponding to the guide groove;
A top cover surrounding an upper edge of the liquid crystal panel and coupled to the support main and the cover bottom;
The guide grooves formed at both edges are positioned closer to the light incident surface than the light incident surface opposite to the light incident surface, so that the light guide plate expands and contracts through the light incident surface side as the temperature increases due to the LED assembly. Display.
The method of claim 1,
And a guide groove formed at both edges of the guide groove is formed in a region closest to the light incident surface, in a region in which both edges are equally divided into three equal widths.
The method of claim 1,
The guide groove formed on the light incident surface is formed at a position of 1/2 of the longitudinal direction of the light incident surface, wherein the guide groove is provided in a form recessed toward the light incident surface from the light incident surface.
The method of claim 3, wherein
The guide groove formed on the light incident surface is formed with a first width and a first depth from the light incident surface toward the light incident surface.
The method of claim 1,
The guide grooves formed at both edges are formed in a concave shape in a direction facing each other, and the guide grooves formed at both edges are formed at a second depth in a direction facing each other. The method according to any one of claims 4 and 5,
And the boss has a diameter equal to the first width and the second width and is smaller than the first depth and the second depth.
The method of claim 1,
The boss is a liquid crystal display device formed of one selected from a cylinder, a polygonal column, a triangular column.
The method of claim 7, wherein
The guide groove is a liquid crystal display device formed of one selected from a semi-circular, polygonal, V-cut type.

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