KR102546419B1 - Light guide plate and backlight unit having the same and liquid crystal display device having the same - Google Patents

Abstract

The present invention relates to a light guide plate, a backlight unit including the same, and a liquid crystal display device including the same, and realizes a narrow bezel by applying a light path changing unit composed of a first pattern and a second pattern to a light entrance part of the light guide plate. It is possible to prevent the occurrence of a dark part in the display area.

Description

A light guide plate, a backlight unit including the same, and a liquid crystal display device including the same

The present invention relates to a light guide plate, a backlight unit including the same, and a liquid crystal display device including the same, and more particularly, to a light guide plate for realizing a narrow bezel, a backlight unit including the same, and a liquid crystal display device including the same.

As the information society develops, the demand for the display field is also increasing in various forms, and in response to this, various flat panel display devices with characteristics such as thinning, light weight, and low power consumption, such as liquid crystal displays A Liquid Crystal Display device, a Plasma Display Panel device, and an Organic Light Emitting Diode Display device are being researched.

Among them, a liquid crystal display device is one of the most widely used flat panel display devices, and includes two substrates on which pixel electrodes and common electrodes are formed, and a liquid crystal layer between the two substrates.

Such a liquid crystal display device determines the alignment of liquid crystal molecules in a liquid crystal layer according to an electric field generated by a voltage applied to two electrodes and controls the polarization of incident light to display an image.

Recently, in manufacturing a liquid crystal display device, it is required to form a display area of the liquid crystal display device to the maximum and form a non-display area (bezel portion) as small as possible.

Hereinafter, a dark part phenomenon that occurs when a bezel part is reduced in a conventional liquid crystal display device will be described with reference to drawings.

1 and 2 are views referenced to explain whether a dark part phenomenon occurs according to a change in the width of a bezel part in a conventional liquid crystal display device.

As shown in FIG. 1 , a conventional liquid crystal display device may include a light guide plate 44, a plurality of light sources 45, a guide panel 60, a cover bottom 70, and the like.

A plurality of light sources 45 may be spaced apart from each other and mounted on a printed circuit board (not shown) at regular intervals.

A plurality of grooves may be formed in the guide panel 60, and a light source 45 may be disposed in each groove.

For example, the light source 45 may emit light having colors of red (R), green (G), and blue (B) toward the light entrance part of the light guide plate 44, respectively. When turned on, white light can be realized by color mixing.

On the other hand, since most of the light emitted from the light source 45 travels forward and light exiting in the side direction is relatively small, the light emitted from the light source 45 is non-uniformly supplied to the light entrance portion of the light guide plate 44, resulting in In the gap between the light sources 45, a dark dark portion BA is generated, resulting in non-uniform luminance.

Therefore, in the conventional liquid crystal display device, the light emitted from the light source 45 is incident into the light guide plate 44 and sufficiently mixed by determining the optical distance as the optical distance and covering the area. ) is set.

That is, the optical distance defined as the distance from the light incident surface of the light guide plate 44 to the display area AA is maintained as much as 'L1' to prevent occurrence of the dark area BA in the display area AA. At this time, L1 may be about 2.5 mm.

However, with the recent implementation of a narrow bezel in a liquid crystal display, the optical distance from the light entrance portion of the light guide plate 44 to the display area AA tends to be gradually narrowed.

As shown in FIG. 2 , if the optical distance from the light incident part of the light guide plate 44 to the display area AA is 'L2', the phenomenon of occurrence of the dark area BA occurs in the display area AA. . At this time, L2 may be about 1.35 mm.

Therefore, in the conventional liquid crystal display device, it is necessary to maintain a certain distance from the light incident portion of the light guide plate 44 to the display area AA in order to prevent the occurrence of the dark area BA from occurring in the display area AA. , there is a problem in that it is difficult to implement a narrow bezel.

The present invention is to solve the above problems, and a light guide plate capable of preventing a dark portion from occurring in a display area when a narrow bezel is implemented by changing the structure of a light entrance portion of the light guide plate, a backlight unit including the same, and the same It is an object of the present invention to provide a liquid crystal display device.

In order to achieve the above object, a light guide plate according to the present invention, a backlight unit including the same, and a liquid crystal display device including the same include a backlight unit including a liquid crystal panel displaying an image, a plurality of light sources, and a light guide plate, and the light guide plate and a light path changing means disposed in the light input portion of the light path changing means, the light path changing means including a first pattern and a second pattern, the first pattern being disposed correspondingly between the neighboring light sources, and the second pattern A pattern is disposed in a region between the first patterns, the first pattern is formed of an embossed prism pattern or an embossed trapezoidal pattern, and the size of the first pattern is larger than that of the second pattern. to provide.

On the other hand, the present invention includes a backlight unit having a liquid crystal panel displaying an image, a plurality of light sources, and a light guide plate, wherein the light entrance part of the light guide plate includes a tapered protrusion and a concave part, and the first pattern, which is the protrusion, is adjacent to It is disposed correspondingly between the light sources, the concave portion is disposed between the neighboring first patterns, and a second pattern is disposed in the concave portion, and the size of the first pattern is greater than the size of the second pattern. A liquid crystal display device is provided.

In addition, the second pattern is made of a side area and a central area between the side areas, the second pattern is made of an embossed lenticular pattern, and the pitch of the lenticular pattern of the side area is the lenticular pattern in the center area. It may have a value smaller than the pitch of the pattern.

Here, a reinforcing pattern may be provided on a rear surface of an area corresponding to the area where the first pattern is formed in the optical distance area of the light guide plate.

Meanwhile, the present invention includes a light guide plate and a light source positioned along a light entrance portion of the light guide plate, and includes a light path changing unit disposed in the light entrance portion of the light guide plate, wherein the light path changing unit separates a first pattern from a second pattern. The first pattern is disposed correspondingly between the adjacent light sources, the second pattern is disposed in a region between the first patterns, and the first pattern is an embossed prism pattern or an embossed trapezoidal pattern. and the size of the first pattern is greater than that of the second pattern.

Meanwhile, a light guide plate and a light source positioned along a light entrance portion of the light guide plate are included, and the light entrance portion of the light guide plate includes a tapered protrusion and a concave portion, and the first pattern, which is the protrusion portion, is disposed to correspond between adjacent light sources, , The concave portion is disposed between adjacent first patterns, and a second pattern is disposed within the concave portion, and a size of the first pattern is larger than that of the second pattern.

In addition, the second pattern is made of a side area and a central area between the side areas, the second pattern is made of an embossed lenticular pattern,

A pitch of the lenticular patterns in the side area may have a smaller value than a pitch of the lenticular patterns in the central area.

In addition, a reinforcing pattern may be provided on a rear surface of an area corresponding to the area where the first pattern is formed in the optical distance area of the light guide plate.

Meanwhile, in the light guide plate of the backlight unit, the present invention includes a plurality of light path changing means spaced apart at regular intervals in the light entrance part of the light guide plate, and the light path changing means includes a first pattern and a second pattern, The first pattern is disposed correspondingly between adjacent light sources, the second pattern is disposed in a region between the first patterns, and the first pattern is formed of an embossed prism pattern or an embossed trapezoidal pattern, A size of the first pattern is greater than that of the second pattern.

On the other hand, the light entrance part of the light guide plate includes a paper-shaped protrusion and a concave part, and the first pattern, which is the protrusion part, is disposed between adjacent light sources, and the concave part is disposed between the adjacent first patterns. A second pattern is disposed in the concave portion, and the size of the first pattern is larger than that of the second pattern.

In addition, the second pattern is made of a side area and a central area between the side areas, the second pattern is made of an embossed lenticular pattern, and the pitch of the lenticular pattern of the side area is the lenticular pattern in the center area. It may have a value smaller than the pitch of the pattern.

In addition, a reinforcing pattern may be provided on a rear surface of an area corresponding to the area where the first pattern is formed in the optical distance area of the light guide plate.

As described above, in the light guide plate according to the present invention, the backlight unit including the same, and the liquid crystal display including the same, the display area when a narrow bezel is implemented by applying the light guide plate having a plurality of light path changing means is applied. It is possible to prevent the occurrence of dark parts in

1 and 2 are views referenced to explain whether a dark part phenomenon occurs according to a change in the width of a bezel part in a conventional liquid crystal display device.
3 is a diagram schematically illustrating a cross section of a liquid crystal display device according to an exemplary embodiment of the present invention.
4 is a schematic diagram of a light guide plate according to a first embodiment of the present invention.
5A and 5B are diagrams illustrating a light path of a backlight unit in a liquid crystal display device according to a first embodiment of the present invention.
6A and 6B are diagrams referenced to describe a light path according to a first embodiment of the present invention.
7 is a schematic diagram of a light guide plate according to a second embodiment of the present invention.
8 is a schematic diagram of a light guide plate according to a third embodiment of the present invention.

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

FIG. 3 is a view schematically showing a cross section of a liquid crystal display device according to an embodiment of the present invention, FIG. 4 is a view schematically showing a light guide plate according to a first embodiment of the present invention, and FIGS. 5A and 5B are It is a diagram showing the light path of the backlight unit in the liquid crystal display according to the first embodiment of the present invention.

As shown in FIG. 3 , the liquid crystal display device according to the present invention may include a liquid crystal panel 130 , a backlight unit 140 , and a cover bottom 170 .

The liquid crystal panel 130 plays a key role in image expression, and includes a first substrate 132 and a second substrate 134 that are bonded to each other with a liquid crystal layer (not shown) therebetween.

At this time, the first substrate 132 has a larger area at one edge than the second substrate 134, and a plurality of gate wires (not shown) and data wires (not shown) are formed at one edge of the first substrate 132. A driving circuit 115 for applying a signal to the time) may be formed.

Also, the first substrate 132 is commonly referred to as an array substrate, and a plurality of pixels (not shown) defined by intersecting gate wires and data wires may be formed on an inner surface of the first substrate 132 .

In such a plurality of pixels, thin film transistors connected to gate wires and data wires, storage capacitors and liquid crystal capacitors connected to the thin film transistors may be formed.

The second substrate 134 is commonly referred to as a color filter substrate, and a color filter layer (not shown) and a black matrix (not shown) may be formed on an inner surface of the second substrate 134 .

Here, the color filter layer includes red, green, and blue color filter patterns (not shown) corresponding to red, green, and blue sub-pixels (not shown).

In addition, the black matrix (not shown) surrounds red, green, and blue color filter patterns (not shown), and non-display elements such as gate wiring (not shown), data wiring (not shown), and thin film transistors (not shown). serves to cover the

Also, a first polarizing plate 136 and a second polarizing plate 138 that selectively transmit only specific light may be attached to outer surfaces of the first substrate 132 and the second substrate 134 , respectively.

The backlight unit 140 includes a reflective sheet 142 , a light guide plate 144 , a plurality of optical sheets 146 , and a light source 145 , and serves to supply light to the liquid crystal panel 130 .

In general, the backlight unit 140 can be largely divided into a side-type backlight unit and a direct-type backlight unit. In the liquid crystal display according to the present invention, a side-type backlight in which an LED assembly is disposed on the inner side of the cover bottom 170 is explained with an example.

The reflective sheet 142 may use a plate having high light reflectance, and when light incident from the light source 145 passes through the lower surface of the light guide plate 144, it reflects toward the liquid crystal panel 130 to improve the luminance of light. do

The reflective sheet 142 may be, for example, an enhanced specular reflector (ESR) having a reflectance of 98% or more.

ESR (Enhanced Specular Reflector) is a reflective sheet that applies the principle of reflecting light by using the difference in refractive index of two different polymer materials composed of multiple layers.

In the light guide plate 144 , light incident from the light source 145 is totally reflected and continues to proceed. As a result, the light is evenly diffused inside the light guide plate 144 to provide a surface light source to the liquid crystal panel 130 .

A printed pattern having a specific shape may be further formed on the lower surface of the light guide plate 144 to supply a uniform surface light source to the liquid crystal panel 130 .

The plurality of optical sheets 146 include a diffusion sheet and at least one light collecting sheet, etc., and diffuse or condense the light passing through the front surface (upper side) of the light guide plate 144 so that the liquid crystal panel 130 is a uniform surface light source. make this supply.

A liquid crystal panel 130 including a first substrate 132 and a second substrate 134 bonded to each other with a liquid crystal layer (not shown) interposed therebetween are disposed on the plurality of optical sheets 146 .

The plurality of light sources 145 may be, for example, light emitting diodes (LEDs), and may be spaced apart from each other and mounted on a printed circuit board (not shown) at regular intervals.

The printed circuit board (not shown) may receive various driving signals for driving a plurality of LEDs through an external driving driver so as to supply light to the liquid crystal panel 130 .

The guide panel 160 serves as an overall skeleton, and a plurality of grooves may be formed on at least one side of the guide panel 160, and a light source 145 may be disposed in each groove.

For example, the light source 145 may emit light having red (R), green (G), and blue (B) colors toward the light entrance part of the light guide plate 144, and the light source 145 may be emitted at once. When turned on, white light can be realized by color mixing.

As such, when the liquid crystal panel 130 and the backlight unit 140 are disposed inside the cover bottom 170 and then combined, the liquid crystal display device module is completed.

In recent years, in manufacturing a liquid crystal display device, it is required to form a display area of the liquid crystal display device to the maximum and form a non-display area (bezel) as small as possible.

That is, the optical distance from the light entrance part of the light guide plate 144 to the display area AA tends to be gradually narrowed according to the implementation of the narrow bezel.

For example, when the optical distance is decreased from L1 to L2, it is difficult to secure a mixing distance of the light source, so that a dark portion BA occurs in the display area AA.

Hereinafter, with reference to FIGS. 4 and 5 , the structure of the light entrance portion of the light guide plate for preventing the occurrence of a dark portion when implementing a narrow bezel in a liquid crystal display device will be described.

As shown in FIG. 4 , a plurality of light path changing means 148 spaced apart at regular intervals may be formed in the light entrance part of the light guide plate 144 .

The light path changing unit 148 includes a first pattern 148a and a second pattern 148b.

In addition, the first pattern 148a is disposed in the light entrance area of the light guide plate 144 corresponding to the area between the light source 145 and the light source 145 . For example, in the case of an LED light source, a first pattern 148a is disposed on a light entrance portion of the light guide plate 144 corresponding to an area between LED packages.

The first pattern 148a of the first embodiment of the present invention may be formed of an embossed prism pattern.

In addition, the first pattern 148a is formed in the light entrance portion of the light guide plate 144 corresponding to the area between the light source 145 and the light guide plate 145, so that the light source 145 and the light guide plate 145 are aligned. ) can play a role.

For example, in the case of an LED light source, when the LED assembly and the light guide plate 144 are disposed, the first pattern 148a is formed in the region of the light guide plate 144 corresponding between the LED package mounted on the LED assembly and the LED package. It may serve as an alignment of the light guide plate 144 .

Meanwhile, the second pattern 148b may be formed of a lenticular pattern spaced apart from each other in a region between the first patterns 148a formed in the light incident portion of the light guide plate 144 .

In particular, the second pattern 148b is disposed by dividing an area between the first patterns 148a into a side area SA and a central area CA between the side areas SA.

That is, the second patterns 148b are characterized in that they are arranged with different pitches in the both side areas SA and the central area CA.

Looking at this in more detail, in the case of the second pattern 148b disposed on the side area SA, the light emitted from the light source 145 is reduced in order to improve the dark portion (BA in FIG. 2) between the light sources 145. In order to spread the pattern widely, the pitch P2 of the second pattern 148b is smaller than that of the central area CA.

On the other hand, in the case of the second pattern 148b disposed in the central area CA, when light emitted relatively strongly from the light source 145 to the central area CA spreads widely, the hot spot ( Since there is a possibility of being recognized as a hot spot, the pitch P1 of the second pattern 148b is increased compared to that of the side area SA so that the light can travel in the light guiding direction of the light guide plate 144.

In addition, the size of the first pattern 148a of the light path changing unit 148 formed in the light entrance portion of the light guide plate 144 is larger than that of the second pattern 148b.

Here, a reinforcing pattern may be partially included in an area between the light entrance portion of the light guide plate 144 and the display area AA of the light guide plate 144 .

That is, the region 144a where the reinforcement pattern is formed corresponds to the region where the first pattern 148a is formed in the optical distance L2 region of the light guide plate 144 . Here, the optical distance L2 means the distance from the light incident surface of the light guide plate 144 to the display area AA.

Since the area 144a where the reinforcing pattern is formed is located between the light sources 145 and the amount of emitted light is relatively small, the rear surface of the light guide plate 144 partially has a lenticular-shaped reinforcing pattern By applying (not shown), a part of the light that is totally reflected within the optical distance L2 of the light guide plate 144 and proceeds in the light guiding direction is emitted to the dark part (BA in FIG. 2 ), so that the dark part can be effectively improved.

As shown in FIG. 5A, the light path changing means 148 of the first embodiment of the present invention is divided into a first pattern 148a and a second pattern 148b, and the first pattern 148a is a light source ( 145) and the light source 145, the path of light emitted from the side surface of the light source 145 through the first pattern 148a is disposed in the light entrance area of the light guide plate 144 corresponding to the area between the dark area BA. can be changed to the area where is generated.

Therefore, the first pattern 148a refracts the light emitted from the side of the light source 145 to the dark area BA generated in the display area AA according to the implementation of the narrow bezel, so that the light generated in the display area AA The dark part BA can be improved.

As shown in FIG. 5B , the second patterns 148b are spaced apart from each other at regular intervals in a region between the first patterns 148a disposed in the light input portion of the light guide plate 144 .

In particular, the second pattern 148b is characterized in that an area between the first patterns 148a is divided into a side area SA and a central area CA between the side areas SA.

Therefore, by increasing the pitch P1 of the second pattern 148b disposed in the central area CA, the amount of light traveling in the light guiding direction of the light guide plate 144 is relatively increased, and the By reducing the pitch P2 of the second pattern 148b, the amount of light traveling between the light sources 145 is relatively increased, resulting in dark portions in the display area AA according to the narrow bezel implementation (FIG. 5A). of BA) can be improved.

6A and 6B are diagrams referenced to describe a light path according to a first embodiment of the present invention.

As shown in FIG. 6A, when the pitch (P1, P2 in FIG. 5B) of the second pattern (148B in FIG. 5B) is large, the light emitted from the light source 145 is relatively concentrated in the central area SA. can be seen becoming

That is, although there is light traveling between the light source 145 where the dark portion BA is generated and the light source 145, the optical distance from the light incident portion of the light guide plate (144 in FIG. 5B) to the display area AA for the narrow bezel ( There is a limit to reducing L2).

As shown in FIG. 6B, when the pitch (P1, P2 in FIG. 5B) of the second pattern (148B in FIG. 5B) is small, a relatively large amount of light emitted from the light source 145 is emitted from the light source ( 145) and light source 145.

However, since the light traveling in the light guiding direction inside the light guide plate 144 decreases and the light traveling to the side increases, the light path F increases and the light efficiency decreases.

Accordingly, the present invention distinguishes the side area SA from the center area CA, and increases the pitch (P1 in FIG. 5B) of the second pattern (148b in FIG. 5B) disposed in the center area CA to relatively By increasing the amount of light traveling in the light guiding direction of the light guide plate 144 and decreasing the pitch (P2 in FIG. 5B) of the second pattern (148b in FIG. 5B) disposed on both side areas SA, the light source 145 is relatively The light efficiency is maintained by increasing the amount of light passing between the light source and the light source 145, and the dark portion BA of the display area AA generated according to the implementation of the narrow bezel can be improved.

In addition, a first pattern ( 148a in FIG. 5A ) is disposed in the light entrance area of the light guide plate 144 corresponding to the area between the light source 145 and the light emitted from the side of the light source 145. By changing the path to an area where the dark part (BA in FIG. 5A) is generated, it is possible to further improve the dark part (BA in FIG. 5A) generated in the display area (AA in FIG. 5A) according to the implementation of the narrow bezel.

7 is a schematic diagram of a light guide plate according to a second embodiment of the present invention.

Hereinafter, descriptions of the same parts as those of the first embodiment are omitted.

As shown in FIG. 7 , a plurality of light path changing means 248 spaced apart at regular intervals may be formed in the light entrance part of the light guide plate 244 .

The light path changing means 248 is composed of a first pattern 248a and a second pattern 248b.

In addition, the first pattern 248a is disposed in the light entrance area of the light guide plate 244 corresponding to the area between the light source 245 and the light source 245 . For example, in the case of an LED light source, a first pattern 248a is disposed in a light entrance portion of the light guide plate 244 corresponding to an area between LED packages.

The first pattern 248a of the second embodiment of the present invention may be formed in an embossed trapezoidal pattern.

In addition, the first pattern 248a is formed in the light entrance portion of the light guide plate 244 corresponding to the area between the light source 245 and the light guide plate 245, so that the light source 245 and the light guide plate 244 are aligned. ) can play a role.

For example, in the case of an LED light source, when the LED assembly and the light guide plate 244 are disposed, the first pattern 248a is formed in the region of the light guide plate 244 corresponding between the LED package mounted on the LED assembly and the LED package. It may serve as an alignment of the light guide plate 244 .

Meanwhile, the second pattern 248b may be formed of a lenticular pattern spaced apart from each other in a region between the first patterns 248a formed in the light incident portion of the light guide plate 244 .

In particular, the second pattern 248b is disposed by dividing an area between the first patterns 248a into a side area SA and a central area CA between the side areas SA.

That is, the second pattern 248b is characterized in that it is disposed with different pitches P1 and P2 in both side areas SA and the central area CA.

Looking at this in more detail, in the case of the second pattern 248b disposed on the side area SA, light emitted from the light source 245 is reduced in order to improve a dark portion (BA in FIG. 5A) between the light sources 245. In order to spread it widely, the pitch value of the second pattern 248b is set to be smaller than that of the central area CA.

Meanwhile, in the case of the second pattern 248b disposed in the central area CA, when light emitted relatively strongly from the light source 245 to the central area CA spreads widely, the hot spot ( Since there is a possibility of being recognized as a hot spot, the pitch P1 is arranged to be larger than that of the side area SA, so that the light can travel in the light guiding direction of the light guide plate 244.

In addition, the size of the first pattern 248a of the light path changing unit 248 formed in the light entering portion of the light guide plate 244 is larger than that of the second pattern 248b.

Here, a reinforcing pattern may be partially included in an area between the light entrance portion of the light guide plate 244 and the display area AA of the light guide plate 244 .

That is, the region 244a where the reinforcement pattern is formed corresponds to the region where the first pattern 248a is formed among the optical distance L2 region of the light guide plate 244 . Here, the optical distance L2 means the distance from the light incident surface of the light guide plate 244 to the display area AA.

Since the area 244a where the reinforcing pattern is formed is located between the light sources 245 and the amount of emitted light is relatively small, the rear surface of the light guide plate 244 partially has a lenticular-shaped reinforcing pattern. (not shown) is applied, a part of the light that is totally reflected within the optical distance L2 of the light guide plate 244 and proceeds in the light guiding direction is emitted to the dark part (BA in FIG. 5a), effectively reducing the dark part (BA in FIG. 5a) can be improved

Accordingly, the present invention divides the side area SA and the central area CA, and increases the pitch P1 of the second pattern 248b disposed in the central area CA to relatively light guide the light guide plate 244. The amount of light traveling in the direction is increased and the pitch P2 of the second patterns 248b disposed on both side areas SA is decreased to relatively increase the amount of light traveling between the light sources 245 and the light sources 245. It is possible to improve the dark portion (BA in FIG. 5A) generated in the display area AA according to the implementation of the narrow bezel while maintaining light efficiency.

In addition, by disposing the first pattern 248a in the light entrance area of the light guide plate 244 corresponding to the area between the light sources 245 and the light source 245, the path of light emitted from the side of the light source 245 is directed to the dark area. (BA in FIG. 5A) is generated, so that the dark portion (BA in FIG. 5A) generated in the display area AA can be further improved according to the implementation of the narrow bezel.

8 is a schematic diagram of a light guide plate according to a third embodiment of the present invention.

Hereinafter, descriptions of the same parts as those of the first embodiment are omitted.

As shown in FIG. 8 , the light entering portion of the light guide plate 344 includes a protruding portion 351 and a concave portion 350 .

The protruding portion 351 is disposed in the light entrance area of the light guide plate 344 corresponding to the area between the light source 345 and the light source 345 . For example, in the case of an LED light source, protruding portions are disposed in the light input portion of the light guide plate 344 corresponding to the area between the LED packages.

Here, the protrusion 351 has the same function as the first pattern 348a in the first and second embodiments.

The protrusion 351 may have a tapered shape, for example, a prism pattern shape, a trapezoidal pattern shape, or other pattern shapes.

In addition, the protruding portion 351 is formed in the light entrance portion of the light guide plate 344 corresponding between the light source 345 and the light guide plate 345 to serve as an alignment when the light source 345 and the light guide plate 344 are disposed. can

For example, in the case of an LED light source, when the LED assembly and the light guide plate 344 are disposed, a protrusion 351 is formed in the region of the light guide plate 344 corresponding between the LED package mounted on the LED assembly and the LED package, so that the LED assembly and the light guide plate ( 344) can serve as an alignment.

Meanwhile, the concave portions 350 are formed between the protruding portions 351 , and second patterns 348b may be formed on the surface of the concave portions 350 at a predetermined interval.

Here, the second pattern 348b formed on the surface of the concave portion 350 may be a lenticular pattern. However, it is not limited thereto.

In particular, the second pattern 348b formed on the concave portion 350 is disposed by dividing an area within the concave portion 350 into a side area SA and a central area CA between the side areas SA.

That is, the second pattern 348b formed in the concave portion 350 is characterized in that it is disposed with different pitches P1 and P2 in the both side areas SA and the central area CA.

Looking at this in more detail, in the case of the second pattern 348b disposed on the side area SA, light emitted from the light source 345 is reduced in order to improve a dark portion (BA in FIG. 5A) between the light sources 345. In order to spread it widely, the pitch P2 of the second pattern 348b is less than that of the central portion CA.

Meanwhile, in the case of the second pattern 348b disposed in the central area CA, when light emitted relatively strongly from the light source 345 to the central area CA spreads widely, the hot spot ( Since there is a possibility of being recognized as a hot spot, the pitch P1 is arranged to be larger than that of the side area SA, so that the light can travel in the light guiding direction of the light guide plate 344.

In addition, a reinforcing pattern may be partially included in an area between the light entrance portion of the light guide plate 344 and the display area AA of the light guide plate 344 .

That is, the area 344a where the reinforcement pattern is formed is an area corresponding to the area where the first pattern 348a, which is a protrusion, is formed in the area of the optical distance L2 of the light guide plate 344 . Here, the optical distance L2 means the distance from the light incident surface of the light guide plate 344 to the display area AA, and more specifically, the distance from the light incident surface of the concave portion 350 to the display area AA. means

Since the area 344a where the reinforcement pattern is formed is located between the light source 345 and the light source 345 has a relatively small amount of emitted light, the rear surface of the light guide plate 344 is partially reinforced with a lenticular shape. By applying a pattern (not shown), a part of the light that is totally reflected within the optical distance L2 of the light guide plate 344 and proceeds in the light guide direction is emitted to the dark part (BA in FIG. 5A), thereby forming the dark part (BA in FIG. 5A). can be effectively improved.

Therefore, in the third embodiment of the present invention, the first pattern 348a, which is the protrusion 351, is formed in the light entrance area of the light guide plate 344 corresponding between the light source 345 and the side surface of the light source 345. By changing the path of the light emitted from the dark portion (BA of FIG. 5A) to the area where the dark portion (BA of FIG. 5A) is generated, it is possible to improve the dark portion (BA of FIG. 5A) generated in the display area AA according to the implementation of the narrow bezel.

In addition, the area of the surface of the concave portion 350 is divided into a side area SA and a central area CA, and the pitch P1 of the second pattern 348b disposed in the central area CA is increased to relatively The amount of light traveling in the light guiding direction of the light guide plate 344 is increased and the pitch P2 of the second patterns 348b disposed on both side areas SA is decreased to relatively pass between the light sources 345 and the light sources 345. Light efficiency is maintained by increasing the amount of light that propagates, and a dark portion (BA in FIG. 5A) generated in the display area AA can be further improved according to the implementation of the narrow bezel.

In the description of the first pattern of the present invention, the embossed prism pattern, the embossed trapezoidal pattern, or the tapered projection of the light guide plate has been described, but this is an example, and is not limited thereto, and light emitted from the light source to the side It may be a pattern of various shapes capable of changing a path of light into the light guide plate.

In explaining the second pattern of the present invention, it has been described as an embossed lenticular pattern. This is an example, but is not limited thereto, and may be patterns of various shapes in which the pitches of the patterns of both side regions and the central region are differently disposed.

The embodiments of the present invention as described above are merely illustrative, and those skilled in the art can freely modify them without departing from the gist of the present invention. Accordingly, the scope of protection of the present invention includes modifications of the present invention within the scope of the appended claims and their equivalents.

144: light guide plate 144a: reinforcement pattern area
145 light source 148 light path changing means
148a: first pattern 148b: second pattern
AA: display area L2: optical distance
CA: center area SA: side area
P1: Pitch of the second pattern in the center area P2: Pitch of the second pattern in the side area

Claims (19)

a liquid crystal panel displaying an image;
It includes a backlight unit having a plurality of light sources and a light guide plate,
a light path changing unit disposed in the light entrance portion of the light guide plate;
The light path changing means includes a first pattern and a second pattern,
The first pattern is disposed correspondingly between the neighboring light sources,
The second pattern is disposed in a region between the first patterns,
The first pattern is composed of an embossed prism pattern or an embossed trapezoidal pattern,
The size of the first pattern is greater than the size of the second pattern,
The second pattern is formed of a side area and a central area between the side areas,
The second pattern is made of an embossed lenticular pattern,
The liquid crystal display device of claim 1 , wherein a pitch of the lenticular patterns in the side regions is smaller than a pitch of the lenticular patterns in the central region.
a liquid crystal panel displaying an image;
It includes a backlight unit having a plurality of light sources and a light guide plate,
The light entrance part of the light guide plate includes a tapered protruding part and a concave part,
The first pattern, which is the protrusion, is disposed to correspond between the neighboring light sources,
The concave portion is disposed between the adjacent first patterns,
A second pattern is disposed within the concave portion,
The size of the first pattern is greater than the size of the second pattern,
The second pattern is formed of a side area and a central area between the side areas,
The second pattern is made of an embossed lenticular pattern,
The liquid crystal display device of claim 1 , wherein a pitch of the lenticular patterns in the side regions is smaller than a pitch of the lenticular patterns in the central region.
delete According to claim 1 or 2,
A liquid crystal display device having a reinforcing pattern provided on a rear surface of an area corresponding to an area where the first pattern is formed in an optical distance area of the light guide plate.
light guide plate;
A light source positioned along the light entrance portion of the light guide plate;
a light path changing means disposed in the light entering portion of the light guide plate;
The light path changing means includes a first pattern and a second pattern,
The first pattern is disposed correspondingly between the neighboring light sources,
The second pattern is disposed in a region between the first patterns,
The first pattern is composed of an embossed prism pattern or an embossed trapezoidal pattern,
The size of the first pattern is greater than the size of the second pattern,
The second pattern is formed of a side area and a central area between the side areas,
The second pattern is made of an embossed lenticular pattern,
A backlight unit in which the pitch of the lenticular patterns in the side region has a smaller value than the pitch of the lenticular patterns in the central region.
light guide plate;
A light source positioned along the light entrance portion of the light guide plate;
The light entering portion of the light guide plate includes a tapered protruding portion and a concave portion,
The first pattern, which is the protrusion, is disposed correspondingly between the neighboring light sources,
The concave portion is disposed between the adjacent first patterns,
A second pattern is disposed within the concave portion,
The size of the first pattern is greater than the size of the second pattern,
The second pattern is formed of a side area and a central area between the side areas,
The second pattern is made of an embossed lenticular pattern,
The backlight unit of claim 1 , wherein a pitch of the lenticular patterns in the side area is smaller than a pitch of the lenticular patterns in the central area.
delete According to claim 5 or 6,
A backlight unit having a reinforcing pattern provided on a rear surface of an area corresponding to an area where the first pattern is formed in an optical distance area of the light guide plate.
In the light guide plate of the backlight unit,
A plurality of light path changing means spaced apart at regular intervals are provided in the light entrance part of the light guide plate,
The light path changing means includes a first pattern and a second pattern,
The first pattern is disposed correspondingly between neighboring light sources,
The second pattern is disposed in a region between the first patterns,
The first pattern is composed of an embossed prism pattern or an embossed trapezoidal pattern,
The size of the first pattern is greater than the size of the second pattern,
The second pattern is formed of a side area and a central area between the side areas,
The second pattern is made of an embossed lenticular pattern,
The light guide plate of claim 1 , wherein a pitch of the lenticular patterns in the side regions is smaller than a pitch of the lenticular patterns in the central region.
In the light guide plate of the backlight unit,
The light entrance portion of the light guide plate includes a paper-shaped protrusion and a concave portion,
The first pattern, which is the protrusion, is disposed correspondingly between neighboring light sources,
The concave portion is disposed between the adjacent first patterns,
A second pattern is disposed within the concave portion,
The size of the first pattern is greater than the size of the second pattern,
The second pattern is formed of a side area and a central area between the side areas,
The second pattern is made of an embossed lenticular pattern,
The light guide plate of claim 1 , wherein a pitch of the lenticular patterns in the side regions is smaller than a pitch of the lenticular patterns in the central region. delete According to claim 9 or 10,
The light guide plate having a reinforcing pattern provided on a rear surface of an area corresponding to an area where the first pattern is formed in an optical distance area of the light guide plate. a light guide plate including a light input unit;
a plurality of light sources disposed along the light incident portion of the light guide plate;
first light path changing means disposed in the light incident portion between the light sources of the light guide plate; and
a second light path changing means disposed between the first light path changing means of the light input unit;
The second light path changing means includes a plurality of first patterns disposed in the center and a plurality of second patterns disposed on both sides of the first pattern;
The backlight unit of claim 1 , wherein a pitch of the plurality of second patterns has a smaller value than a pitch of the plurality of first patterns.
14. The backlight unit according to claim 13, wherein the first light path changing unit is formed of a prism pattern with embossed edges. 14. The backlight unit according to claim 13, wherein the first light path changing unit is configured in an embossed trapezoidal pattern.
14. The backlight unit according to claim 13, wherein the first light path changing means comprises a protrusion formed on the light incident surface of the light guide plate.
14. The backlight unit according to claim 13, wherein the second light path changing means comprises an embossed lenticular pattern.
14. The backlight unit according to claim 13, wherein the second light path changing means comprises a concave portion formed on the light incident surface of the light guide plate.
a liquid crystal panel displaying an image; and
A display device comprising the backlight unit according to claims 13 to 18, disposed on one side of the liquid crystal panel and supplying light to the liquid crystal panel.

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