KR102110296B1 - Liquid crystal display device - Google Patents

Abstract

The present invention relates to a liquid crystal display device, including a liquid crystal panel, a backlight unit located on the rear surface of the liquid crystal panel including a light source disposed on the side, a cover bottom portion covering the back and side surfaces of the backlight unit, and the cover bottom It is provided along at least one inner surface of the portion and includes light leakage preventing means for preventing light leakage occurring between at least one inner surface of the cover bottom portion and a side surface of the backlight unit.
Through this, it is possible to implement a liquid crystal display device having a narrow bezel while being lightweight and thin, and light leakage that may occur between the display area and the non-display area can be prevented.

Description

Liquid crystal display device {LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a liquid crystal display device, and more particularly, to a liquid crystal display device having a narrow bezel.

In accordance with the recent information age, the display field has also rapidly developed, and in response, a liquid crystal display device (LCD) and organic light emitting display device having advantages of thinning, lightening, and low power consumption. 2. Description of the Related Art Diode (organic light emitting diode) displays have excellent performance and are widely used.

Here, a liquid crystal display device (LCD), which is actively used in TVs, monitors, and mobile phones because it is advantageous for moving picture display and has a large contrast ratio, is an optical anisotropy and polarization of liquid crystal. It shows the principle of imaging by polarization.

This liquid crystal display device is a liquid crystal panel (liquid crystal panel) bonded by interposing a liquid crystal layer between two parallel substrates (substrate), and the electric field in the liquid crystal panel to change the arrangement direction of the liquid crystal molecules to realize the difference in transmittance do.

However, since the liquid crystal panel does not have a light emitting element, a separate light source is required to display the difference in transmittance as an image. To this end, a backlight unit having a light source is disposed on the rear surface of the liquid crystal panel.

Here, the backlight unit is divided into a direct type and an edge type according to the position of the light source. In the direct type backlight unit, the light emitted from the light source is directly disposed by placing the light source under the liquid crystal panel. A method of supplying to a liquid crystal panel, and the backlight unit of the side type method indirectly injects light emitted from the light source by using refraction and reflection in the light guide plate by arranging the light guide plate under the liquid crystal panel and placing the light source on at least one side of the light guide plate. It is a method of supplying to a liquid crystal panel.

At this time, the side type backlight unit not only can reduce the number of LEDs, but also has the advantage of slimming by reducing the thickness of the entire liquid crystal display device, and is a popular trend.

The liquid crystal panel and the backlight unit are modularized into a liquid crystal display module by a top cover, a support main and a cover bottom.

Meanwhile, in recent years, the liquid crystal display device is designed to implement a liquid crystal display device having a lightweight, thin and narrow bezel while having a wide display area as the use areas of the portable computer, desktop computer monitors and wall-mounted televisions are diversified. Research is being actively conducted, but there is a problem in that there are too many components that modularize the liquid crystal display device, and thus there is a limitation.

In addition, each of the components that modularize the liquid crystal display device protects and stores the liquid crystal panel and the backlight unit, and also serves to prevent an unwanted light leakage phenomenon related to visibility, thereby making it difficult to reduce components easily.

In particular, in the case of the support main, it is difficult to omit it because it distinguishes the liquid crystal panel from the backlight unit and also serves to prevent the light leakage from the side of the backlight unit.

An object of the present invention to solve the above problems is to provide a liquid crystal display device having a light weight and thin and narrow bezel by minimizing the components that modularize the liquid crystal display device while preventing light leakage.

A liquid crystal display device according to an embodiment of the present invention for achieving the above object, a liquid crystal panel; A backlight unit including a light source disposed on a side and located on a rear surface of the liquid crystal panel; It is provided along at least one inner surface of the cover bottom portion and the cover bottom portion that covers the back and side surfaces of the backlight unit, and prevents light leakage that prevents light leakage occurring between at least one inner surface of the cover bottom portion and the side surface of the backlight unit. Means.

Here, the cover bottom portion is characterized in that it consists of a first cover bottom of a rectangular plate shape, a second cover bottom including a vertical portion perpendicular to the horizontal portion and the horizontal portion in contact with the first cover bottom.

In addition, the light leakage preventing means is characterized in that it consists of a first portion having a higher reflectance than the absorbance, and a second portion having a higher absorbance than the reflectance.

In this case, the first portion is white or gray color, and the second portion is black.

The liquid crystal display according to the present invention further includes a light guide plate facing the light source, the first portion having a first height corresponding to the thickness of the light guide plate, and the second portion having a second height and the first It is characterized in that the light leakage preventing means is formed to cover at least one inner surface of the cover bottom part by being positioned on the upper part.

In addition, the liquid crystal panel is divided into a display area displaying an image and a non-display area bordering the display area and having a light-shielding process, and some light reflected from the first part is incident on the side surface of the light guide plate and the liquid crystal It is characterized in that it is emitted to the outside through the display area of the panel, and some light reflected from the second portion is blocked by the non-display area.

In addition, an adhesive means for fixing the liquid crystal panel is further provided as a rear edge of the liquid crystal panel.

Here, the adhesive means is partially attached between the rear edge of the liquid crystal panel and the corresponding cover bottom portion, and the rest is bent at a right angle in the lateral direction of the cover bottom portion and is attached along the outer surface of the cover bottom portion. Is done.

This, the adhesive means is characterized in that the black.

As described above, according to the liquid crystal display device according to the exemplary embodiment of the present invention, the conventional top cover and the support main are omitted to minimize components and realize a light weight and a thin shape, and also reduce the width of the non-display area to minimize the width of the bezel. I can do it. In addition, it is possible to reduce component costs by omitting components.

In particular, the light leakage phenomenon on the side of the backlight unit, which may be caused by omitting the support main, is prevented by configuring the light leakage preventing means on the inner surface of the cover bottom portion.

1 is a cross-sectional view showing a liquid crystal display device according to an exemplary embodiment of the present invention.
Figure 2 is a perspective view showing the backlight unit and the cover bottom of Figure 1;
3 is an enlarged cross-sectional view of the AB region in the liquid crystal display of FIG. 1.
4 is a view showing light leakage prevention in a liquid crystal display device according to an exemplary embodiment of the present invention.
Figure 5a is a front view showing another example of the light leakage preventing means according to an embodiment of the present invention.
Figure 5b is a cross-sectional view showing another example of the light leakage preventing means according to an embodiment of the present invention.
6 is a cross-sectional view showing another example of a liquid crystal display device according to an embodiment of the present invention.

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

1 is a cross-sectional view showing a liquid crystal display device according to an embodiment of the present invention, FIG. 2 is a perspective view showing a backlight unit and a cover bottom portion of FIG. 1, and FIG. 3 is an enlarged cross-sectional view of the AB region in the liquid crystal display device of FIG. 1 4 is a view showing light leakage prevention in a liquid crystal display according to an exemplary embodiment of the present invention.

As illustrated, the liquid crystal display device 100 includes a liquid crystal panel 110 and a backlight unit 120, and a cover bottom 150 for modularizing the liquid crystal panel 110 and the backlight unit 120.

The liquid crystal panel 110 is a part that plays a key role in image expression, and is composed of first and second substrates 112 and 114 bonded to each other with a liquid crystal layer interposed therebetween.

Here, the first substrate and the second substrate 112 and 114 may be divided into a display area DA that implements an image and a non-display area NDA that borders the display area DA and does not implement an image.

First and second polarizing plates 119a and 119b which selectively transmit only specific light are attached to the outer sides of the first and second substrates 112 and 114, respectively.

In this case, although not shown on the drawing, the non-display area NDA is displayed in the non-display area NDA of the first substrate 112, the second substrate 114, or both the first substrate 112 and the second substrate 114. At the same time, the light blocking treatment may be performed to block the light leakage phenomenon. The light blocking process may be provided in the form of a light blocking pattern or a light blocking tape, for example, between the first polarizing plate 119a and the first substrate 112 or between the second polarizing plate 119b and the second substrate 114 It may be provided between the first polarizing plate 119a and the first substrate 112 and between the second polarizing plate 119b and the second substrate 114.

On the other hand, under the premise of an active matrix method, a plurality of gate lines and data lines are crossed to define a pixel on the inner surface of the first substrate 112, commonly referred to as a lower substrate or an array substrate, and a thin film transistor (Thin Film Transistor) at each intersection point. TFT) is provided to be connected one-to-one with the transparent pixel electrode formed in each pixel.

In addition, as an example corresponding to each pixel on the inner surface of the second substrate 114 called an upper substrate or a color substrate, color filters of red (R), green (G), and blue (B) colors, and these A black matrix covering each of the non-display elements such as a gate line, a data line, and a thin film transistor, and a transparent common electrode covering them are provided. Here, the transparent common electrode may be formed on the first substrate 112.

A printed circuit board (not shown) is connected via a connecting member (not shown) such as a flexible circuit board or a tape carrier package (TCP) along one edge of the liquid crystal panel 110. At this time, the printed circuit board (not shown), although not shown in the drawing, may be in close contact with the back of the cover bottom part 150 in the modularization process.

Accordingly, the liquid crystal panel 110 of the above-described structure, when the thin film transistor selected for each gate line is turned on by the on or off signal of the gate driving circuit transmitted through the printed circuit board (not shown), the data driving circuit The signal voltage is transmitted to the corresponding pixel electrode through the data line, and accordingly, the arrangement direction of the liquid crystal molecules is changed by the electric field between the pixel electrode and the common electrode, thereby indicating a difference in transmittance.

On the other hand, although not shown on the drawing, a sealing portion having elasticity and absorbing external shock may be provided on the side surface of the other edge except for one edge of the liquid crystal panel 110.

At this time, the sealing portion may be formed of a dark color of the black series, which is intended to be absorbed by the sealing portion even if the light by the backlight unit 120 is guided to the side of the first substrate 112 or the second substrate 114. As a result, light leakage phenomenon that may be generated through the side of the first substrate 112 or the second substrate 114 is prevented.

A backlight unit 120 is provided on the rear surface of the liquid crystal panel 110 to supply light to display a difference in transmittance as an image.

The backlight unit 120 includes a light source arranged along one inner surface 150a of the cover bottom portion 150, a reflector plate 125, a light guide plate 123 mounted on the reflector plate 125, and interposed therebetween. It includes a plurality of optical sheets 121.

For example, the LED 129a is used as a light source, and each of the plurality of LEDs 129a is spaced apart at regular intervals and mounted on an LED printed circuit board (LED PCB, 129b), thereby allowing the LED assembly 129 ).

At this time, the LED printed circuit board 129b may correspond to a metal core printed circuit board (MCPCB) having a heat dissipation function for dissipating heat generated from a plurality of LEDs 129a.

In the LED assembly 129, the light emitted from the plurality of LEDs 129a faces one side 123a corresponding to the light incident surface of the light guide plate 123, such as by adhesion or the like. It is fixed to the side.

Accordingly, light emitted from the plurality of LEDs 129a of the LED assembly 129 enters the light guide plate 123 and is supplied to the liquid crystal panel 110 using refraction and reflection in the light guide plate 123.

On the other hand, although not shown in the drawing, the rear surface of the LED assembly 129 may be provided with an LED housing (not shown) for more efficiently dissipating heat generated from each of the plurality of LEDs (129a).

The reflector 125 improves the luminance of light by reflecting light passing through the rear surface of the light guide plate 123 toward the liquid crystal panel 110 in a square plate shape.

The light guide plate 123 guides the light emitted from each of the plurality of LEDs 129a to implement a higher quality surface light source.

The light guide plate 123 has a square plate shape, and may include a pattern of a specific shape on the back surface to supply a uniform surface light source.

The pattern may be variously configured, such as an elliptical pattern, a polygonal pattern, or a hologram pattern, to guide the light incident into the light guide plate 123. The light guide plate 123 may be formed on a lower surface of a printing method or an injection method.

Such a pattern may be formed with a uniform spacing and size, but is not limited thereto, and as the distance from the plurality of LEDs 129a, which are light sources, the spacing between the patterns becomes uniform, but may be formed such that the size of the pattern increases. As the distance from the LED 129a of the pattern is uniform, the gap between the patterns may be reduced.

The light guide plate 123 for this purpose may be made of polymethyl methacrylate (PMMA) or polymethacrylstyrene (MS) resin in which polymethyl methacrylate (PMMA) and polystyren (PS) are mixed. have.

The plurality of optical sheets 121 interposed on the light guide plate 123 diffuses or collects the light converted by the light guide plate 123 to a surface light source so that a more uniform surface light source is incident on the liquid crystal panel 110. .

The plurality of optical sheets 121 may include a diffusion sheet for diffusing light, and at least one prism sheet and a protection sheet for condensing light.

The above-described liquid crystal panel 110 and the backlight unit 120 are modularized through the cover bottom part 150. At this time, the liquid crystal panel 110 is fixed to the cover bottom part 150 by the edge rear surface of the liquid crystal panel 110. An adhesive pad (not shown) is provided to allow the liquid crystal panel 110 and the backlight unit 120 to be bound to each other.

Here, the cover bottom portion 150, which is the basis of the entire mechanism, covers the back and side surfaces of the backlight unit 120 and accommodates the backlight unit 120.

The cover bottom 150 for this purpose is perpendicular to the first cover bottom 152 having a rectangular plate shape, and the horizontal portion 153 and the horizontal portion 153 overlapping and contacting the first cover bottom 152. It is composed of a second cover bottom 155 including one vertical portion (154).

The cover bottom part 150 may have a silver color.

The cover bottom portion 150 having such a structure is intended to reduce the width of the bezel by configuring the side thinner, wherein the bottom side is thicker than the side, so that the backlight unit 120 is stored more stably, and the liquid crystal The panel 110 and the backlight unit 120 are supported.

The cover bottom part 150 may be integrally formed.

On the other hand, the inner surface (150a, 150b) of the cover bottom portion 150 may be provided with an LED assembly 129 and a light leakage preventing means 160, respectively, on one inner surface (150a) of the cover bottom portion 150 When the LED assembly 129 is provided, it is characterized in that the light leakage preventing means 160 is provided on at least the other inner surface 150b except for one inner surface. Meanwhile, the LED assembly 129 is provided on each of the inner surfaces of the cover bottom 150 facing each other without being limited to the illustrated bar, and the light leakage preventing means 160 may be provided on each of the remaining inner surfaces.

Here, the light leakage preventing means 160 is for preventing light leakage that may occur between the side surface of the backlight unit 120 and the inner surface of the cover bottom portion 150, the first part for reflecting a part of light ( 162) and a second portion 164 for absorbing most of the light.

The first portion 162 has a color of white or gray, and is formed at a height H1 corresponding to the thickness of the side surface of the light guide plate 123 and is emitted through the side surface of the light guide plate 123 By absorbing a part of the light and reflecting a part of the light, the light intensity of the liquid crystal display device is not reduced, and at the same time, the light efficiency is increased.

The first portion 162 is characterized in that the reflectance is higher than the absorption.

At this time, the first portion 162 may have a different color according to the structure of the pattern included on the back surface of the light guide plate 123, the second side surface of the light guide plate 123 by the pattern included on the back surface of the light guide plate 123 ( When the intensity of light emitted through 123b) is strong, it can be implemented in a light gray color to absorb a larger amount of light, and when the intensity of light is weak, it can be white to absorb a smaller amount of light. Can be implemented. For example, as the distance from the plurality of LEDs 129a increases the intensity of the light by making the size of the pattern uniform but the spacing between the patterns decreases, the first portion 162 may be implemented in a gray color. At this time, the first part 162 is preferably the first part 162 of the light leakage preventing means 160 formed on the other inner surface facing the inner surface of the cover bottom portion 150a where the LED assembly 129 is disposed. Do.

The second portion 164 has a black color, and is formed of a second height H2 to cover the entire inner surface of the vertical portion 154 of the second cover bottom 155 together with the first portion 162, the light guide plate By absorbing most of the light emitted through the side surfaces of the 123 and the plurality of optical sheets 121, light leakage can be prevented.

The second portion 164 is characterized in that the absorption rate is higher than the reflectance.

Meanwhile, the first part is not limited to white or gray-based colors, and a color having a higher reflectance than the absorbance may be applied, and the second part is not limited to black, and a color having a higher absorbance than the reflectance is used. It can also be applied.

The traveling path of the light by the light leakage preventing means 160 will be described with reference to FIG. 3.

As illustrated in FIG. 3, the first light L11 emitted through the second side surface 123b of the light guide plate 123 and having the first luminance is caused by the first portion 162 of the light leakage preventing means 162. Some of the light is absorbed and has a second luminance lower than the first luminance, and the reflected first light L12 is reflected through the side surface of the light guide plate 123 or the plurality of optical sheets 121 or the light guide plate 123 or a plurality of It is incident on the inside of the optical sheets 121, and the incident first light L13 is emitted through the display area DA of the liquid crystal panel 110.

In addition, the second light L21 emitted through the second side 123b of the light guide plate 123 and having the first luminance is mostly absorbed by the second portion 164 of the light leakage preventing means 162, at this time. When the light of the light has a third luminance lower than the first and second luminances and is reflected, the reflected second light L22 is blocked by the non-display area NDA of the liquid crystal panel 110 so that it cannot be emitted to the outside. do.

As described above, the first part 162 of the light leakage preventing means 160 absorbs part of the light emitted from the second side surface 123b of the light guide plate 123, and partially reflects the light to exit through the display area of the liquid crystal panel. By doing so, the light efficiency of the liquid crystal display device 100 is eventually increased. Further, the second portion 164 of the light leakage preventing means 160 absorbs most of the light emitted from the second side 123b of the light guide plate 123. At this time, even if a portion of the second portion 164 is reflected, since it is blocked from the non-display area NDA of the liquid crystal panel 110 and cannot be emitted, the side surface of the backlight unit 120 as shown in FIG. Light leakage phenomenon that may occur between the inner surfaces of the cover bottom portion 150 is prevented. The AC area of FIG. 4 is an area corresponding to the AB area of FIG. 3, and is applied between the display area DA and the non-display area NDA of the liquid crystal panel 110 by applying the light leakage preventing means 160 according to the present invention. It can be seen that the light leakage phenomenon that occurred was prevented.

In more detail, if there is no light leakage preventing means 160, light emitted through the side surface of the light guide plate is reflected on the inner surface of the cover bottom part, and light leakage phenomenon is recognized through the display area of the liquid crystal panel. In the related art, the light leakage phenomenon that may be generated between the side surface of the backlight unit and the inner surface of the cover bottom is prevented through the support main, but in the present invention, the first part that slightly reflects light and the second part that absorbs most of the light It characterized in that by preventing the light leakage phenomenon by providing a light leakage preventing means (160) consisting of.

According to the liquid crystal display device 100 having the above-described structure, the light emitted from each of the plurality of LEDs 129a of the backlight unit 120 enters the light input portion of the light guide plate 123, and thereafter the liquid crystal panel ( It is refracted toward 110) and is processed into a more uniform high-quality surface light source while passing through the plurality of optical sheets 121 together with light reflected by the reflector 125 to be supplied to the liquid crystal panel 110.

As described above, in the liquid crystal display device 100 according to an exemplary embodiment of the present invention, light leakage may be prevented even though the components of the conventional top cover and the support main are omitted. In addition, the cost of parts is reduced by omitting the components, and further, the overall production cost is reduced, and at the same time, it is possible to implement a liquid crystal display device having a minimum bezel width while being lightweight and thin.

Hereinafter, another example of the light leakage preventing means according to the present invention will be described with reference to the drawings.

5A is a front view showing another example of the light leakage preventing means according to the embodiment of the present invention, and FIG. 5B is a cross-sectional view showing another example of the light leakage preventing means according to the embodiment of the present invention.

5A and 5B, the light leakage preventing unit 160 is formed of a first portion 162 having a white or gray color and a black portion formed on the upper portion thereof. It consists of two parts (164).

The light leakage preventing unit 160 corresponds to a light weight and thin cross-section adhesive tape, and has a bar shape having a first length L and a first width W1.

Here, the first portion 162 has a first width W1, and the second portion 164 is a second width W2 from an edge portion of the first portion 162 to the top of the first portion 162 ) And overlaps with the first portion 162 to make contact.

Accordingly, the light leakage preventing means 160 has a double layer structure, and the first portion 162 is partially covered by the second portion 164, as shown in FIG. 3, corresponding to the first height H1 It will have a width. At this time, the second portion 164 has a second width W2 corresponding to the second height H2.

On the other hand, the liquid crystal display device according to the present invention may include an adhesive means for a more solid binding in modularizing the liquid crystal panel and the backlight unit.

This will be described with reference to the drawings.

6 is a cross-sectional view showing another example of a liquid crystal display according to an embodiment of the present invention. Here, since the structure except the adhesive means is the same as in FIG. 1, the same reference numerals are given and detailed descriptions of the same components are omitted.

As shown in FIG. 6, the liquid crystal display device 100 includes a liquid crystal panel 110 and a backlight unit 120, and a cover bottom 150 for modularizing the liquid crystal panel 110 and the backlight unit 120. It includes an adhesive means (180).

Here, the adhesive means 180 may correspond to a lightweight and thin adhesive tape, and may have a black color. In this case, the light blocking treatment formed on the non-display area of the liquid crystal panel 110 may be omitted.

The adhesive means 180 may be provided as a rear edge of the liquid crystal panel 110 to perform a role of fixing the liquid crystal panel 110 and perform a light blocking function.

In particular, the bonding means 180 is provided as a rear edge of the liquid crystal panel 110 and is bent to be attached along the outer surface of the cover bottom portion 150, so that the binding between the liquid crystal panel 110 and the backlight unit 120 is more It can be done solidly.

In more detail, the adhesive means 180 is partially provided between the rear edge of the liquid crystal panel 110 and the upper surface of the vertical portion 154 of the cover bottom 150 corresponding to the liquid crystal panel 110, and the rest is covered with the cover bottom ( Bend at a right angle in the lateral direction of 150) is attached along the outer surface of the cover bottom 150.

The embodiments of the present invention as described above are merely exemplary, and a person having ordinary knowledge in the technical field to which the present invention pertains can freely deform without departing from the gist of the present invention. Accordingly, the protection scope of the present invention includes the appended claims and modifications of the present invention within the scope equivalent thereto.

100: liquid crystal display 110: liquid crystal panel
120: backlight unit 123: light guide plate
150: cover bottom part 152: first cover bottom part
155: second cover battle 160: light leakage prevention means
162: first part 164: second part
180: bonding means

Claims (11)

A liquid crystal panel;
A backlight unit including a light source disposed on a side and located on a rear surface of the liquid crystal panel;
A cover bottom portion covering the back and side surfaces of the backlight unit, and
Light leakage preventing means provided along at least one inner surface of the cover bottom portion to prevent light leakage occurring between at least one inner surface of the cover bottom portion and a side surface of the backlight unit;
It includes,
The light leakage preventing means is a liquid crystal display device consisting of a first portion having a higher reflectance than the absorbance, and a second portion having a higher absorbance than the reflectance.
According to claim 1,
The cover bottom portion is a liquid crystal display device comprising a first cover bottom in the shape of a square plate, a second cover bottom including a horizontal portion vertically perpendicular to the horizontal portion and a horizontal portion in contact with the first cover bottom. .
delete According to claim 1,
The first portion is white or gray color,
The second portion is a liquid crystal display device, characterized in that black.
According to claim 1,
Further comprising a light guide plate facing the light source,
The first portion has a first height corresponding to the thickness of the light guide plate,
The second portion has a second height and is located on the upper portion of the first portion.
The light leakage preventing means is formed so as to cover at least one inner surface of the cover bottom portion.
The method of claim 5,
The liquid crystal panel is divided into a display area displaying an image and a non-display area bordering the display area and performing light blocking processing,
Some light reflected from the first portion is incident on the side surface of the light guide plate and is emitted to the outside through the display area of the liquid crystal panel,
A liquid crystal display device, characterized in that some light reflected from the second portion is blocked by the non-display area.
According to claim 1,
A liquid crystal display device characterized by further comprising an adhesive means for fixing the liquid crystal panel to the rear edge of the liquid crystal panel.
The method of claim 7,
The adhesive means
A liquid crystal display device, characterized in that a part is attached between the rear edge of the liquid crystal panel and the corresponding cover bottom part, and the rest is bent at a right angle in the lateral direction of the cover bottom part and attached along the outer surface of the cover bottom part.
The method of claim 7,
The adhesive means is a liquid crystal display device, characterized in that black.
According to claim 1,
The light source is disposed on a first side of the backlight unit, and the light leakage preventing means is located between a second side of the backlight unit perpendicular to the first side and at least one inner surface of the cover bottom portion.
According to claim 1,
The cover bottom part includes a bottom part and a side part, and the thickness of the bottom part is greater than the thickness of the side part.

Images