KR20160070893A - Variable display device - Google Patents

Abstract

The present invention relates to a variable display device that can switch between a flat mode and a curved mode and a method of driving a flat mode and a curved mode thereof. The feature of the present invention is to form a plurality of cutting grooves along both edges in a length direction of an FPBC of an LED assembly that is a light source of a liquid crystal display device of the variable display device. Accordingly, the variable display device can prevent stress from being concentrated on the FPCB even when switching between a convex curved mode, a concave curved mode, and a flat mode, thus avoiding damage to the FPCB. Therefore, luminance of the variable display device can be prevented from being decreased, and quality of the variable display device, such as luminance and image quality, can be avoided from being degraded.

Description

[0001] Variable display device [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention [0002] The present invention relates to a variable display device that can be used in a flat mode and a curved mode.

2. Description of the Related Art [0002] In recent years, as the society has become a full-fledged information age, a display field for processing and displaying a large amount of information has rapidly developed, and a variety of flat display devices have been developed Be in the spotlight.

Specific examples of such a flat panel display device include a liquid crystal display device (LCD), a plasma display panel (PDP), a field emission display (FED) Devices such as an electroluminescence display device (ELD) and an organic light emitting diode (OLED). These flat panel display devices have excellent performance in reducing the thickness, weight, and power consumption of a conventional cathode ray tube : CRT).

Such a flat panel display device has advantages of high image quality, ultra-thinness, light weight and large size, has advantages of space utilization, interior and design, and can have various application fields.

In recent years, a flat panel display device has been rapidly emerging as a next generation display device as a curved display device having a curved surface. The curved display device allows a user to further improve the degree of immersion, To feel comfortable, or to have a larger viewing radius than a flat panel display.

In recent years, there has been a demand for research on a variable display device capable of satisfying all the advantages of a flat panel display device and a curved display device having an immersion degree and a wide viewing radius.

In order to improve the space usability, the variable display device is operated in the flat panel mode. In order to improve the immersion feeling or to realize a wider viewing radius, the user can operate the flat panel mode in the curved surface mode. .

Meanwhile, since the LED assembly, which is a light source of a backlight unit for supplying light from the variable display device to the liquid crystal panel, has a plurality of LEDs mounted on a PCB made of a metal material, It is difficult to change the situation.

Particularly, in the process of varying the variable display device into the planar mode and the curved surface mode, the stress is concentrated on the PCB and the PCB is damaged. This causes a problem that the quality of the display device is deteriorated do.

SUMMARY OF THE INVENTION It is an object of the present invention to prevent damage to an LED assembly of a backlight unit in a variable display device capable of implementing both a flat display device and a curved display device, do.

A second object of the present invention is to prevent degradation of the quality of the variable display device.

In order to achieve the above object, the present invention provides a liquid crystal display comprising: a liquid crystal panel; A light guide plate positioned below the liquid crystal panel; And a flexible printed circuit board (FPCB) disposed corresponding to the light incident surface of the light guide plate and having a plurality of LEDs, a plurality of LEDs, and a plurality of cut grooves spaced along both side edges in the longitudinal direction, Wherein the FPCB is bent in a direction perpendicular to a normal line of a mounting surface on which the plurality of LEDs are mounted.

At this time, the liquid crystal panel and the LED assembly may be formed in a flat mode, a convex curved mode or a concave curved mode, which forms a convex or concave curved surface, wherein the plurality of cut grooves are formed of first and second inclined surfaces, and the vertexes of the plurality of cut grooves provided at the first edge in the longitudinal direction of the FPCB are arranged at a second edge in the longitudinal direction of the FPCB The vertexes of the plurality of cut grooves facing each other face each other.

(N은 상수, n은 상기 FPCB의 일 가장자리를 따라 형성된 상기 컷팅홈의 개수, d는 상기 제 1 및 제 2 경사면 사이의 간격, W는 상기 FPCB의 폭, R_θ는

(R은 휨이 발생된 상기 FPCB의 중심부를 기준으로 한 원의 반지름))의 식을 통해 정의되며, 상기 가변형 표시장치가 상기 볼록 곡면형 모드(convex curved mode)일 때, 상기 FPCB는 상기 양측 가장자리가 상기 액정패널을 향해 볼록하게 휜다. The sum of the intervals between the first and second inclined surfaces of the plurality of cut grooves is

(N is a constant, n is the number of the cut groove formed along the one edge of the FPCB, d is the spacing between the first and second inclined surfaces, W is the width of the FPCB, _θ R is

(Where R is a radius of a circle with respect to a central portion of the FPCB where warpage has occurred)), and when the variable display device is in the convex curved mode, the FPCB is defined by the two sides And the edge is convexly curved toward the liquid crystal panel.

The gap between the first and second inclined surfaces of the plurality of cut grooves provided at the first edge of the FPCB facing the liquid crystal panel may be greater than the distance between the first and second inclined surfaces of the plurality of cut grooves provided at the second edge And when the variable display device is in the concave curved mode, the FPCB is concavely curved toward both sides of the liquid crystal panel.

At this time, the gap between the first and second sloping faces of the plurality of cutting grooves provided at the first edge of the FPCB facing the liquid crystal panel may be greater than the distance between the first and second sloping faces of the plurality of cutting grooves provided at the second edge And the second inclined surface.

As described above, by forming a plurality of cutting grooves along both longitudinal edges of the FPCB of the LED assembly which is the light source of the liquid crystal display of the variable display device according to the present invention, the variable display device can be formed in a convex- The curved surface mode, and the flat plate type mode, it is possible to prevent the stress from being concentrated by the FPCB, thereby preventing the FPCB from being damaged.

Therefore, it is possible to prevent the problem of lowering the luminance of the variable display device, and it is possible to prevent the problem that the quality of the variable display device such as luminance and image quality deteriorates.

1A to 1C are perspective views schematically showing a variable display device according to an embodiment of the present invention.
2 is a perspective view schematically showing a liquid crystal display device of a variable display device according to an embodiment of the present invention.
3 is a perspective view schematically showing an LED assembly of a liquid crystal display of a variable display device according to an embodiment of the present invention.
Figs. 4a-4b are plan views schematically illustrating warpage of the LED assembly of Fig. 3a. Fig.

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

FIGS. 1A to 1C are perspective views schematically showing a variable display device according to an embodiment of the present invention, and FIG. 2 is a perspective view schematically showing a liquid crystal display device of a variable display device according to an embodiment of the present invention.

As shown, the variable display device 100 according to an embodiment of the present invention includes a liquid crystal display device 110 for realizing images, an external case 160 and 170 for accommodating the liquid crystal display device 110, And a pedestal 180 connected to a lower end portion or a back portion of the outer case 160 or 170 and fixed to a desk or a wall.

Here, a liquid crystal display device (LCD) 110 is advantageous for moving picture display and has a large contrast ratio, and thus has a feature of being actively used in a TV, a monitor, and the like.

The liquid crystal display device 110 includes a liquid crystal panel 111 formed by laminating liquid crystal layers between two adjacent substrates as an essential component. The liquid crystal display device 110 includes an array of liquid crystal molecules Direction is changed to realize a difference in transmittance.

Since the liquid crystal panel 111 does not have its own light emitting element, a separate light source is required to display the difference in transmittance as an image. To this end, a backlight unit (light source) backlight unit 120 is disposed.

2, the liquid crystal display device 110 includes a liquid crystal panel 111 and a backlight unit 120. The liquid crystal panel 111 includes a liquid crystal panel 111, And includes a first substrate 112 and a second substrate 114 which are bonded to each other with a liquid crystal layer interposed therebetween.

At this time, a plurality of gate lines and data lines intersect with each other on the inner surface of the first substrate 112, which is usually referred to as an array substrate, although not shown in the drawing, on the premise that the active matrix method is employed. Pixels are defined, And a thin film transistor (TFT), which are connected in a one-to-one correspondence with the transparent pixel electrodes formed in the respective pixels.

On the inner surface of the second substrate 114 called a color filter substrate, a color filter of red (R), green (G), and blue (B) And a black matrix for covering non-display elements such as a gate line, a data line and a thin film transistor.

On the inner surface of the second substrate 114, transparent common electrodes covering the respective color filters and the black matrix are provided.

A polarizing plate (not shown) for selectively transmitting only specific light is attached to the outer surfaces of the first and second substrates 112 and 114, respectively.

The printed circuit board 118 is connected to at least one edge of the liquid crystal panel 111 via a connection member 116 such as a flexible circuit board or a tape carrier package (TCP) And is brought into close contact with the back surface of the liquid crystal panel 111 as appropriate.

In the liquid crystal panel 111 having the structure described above, when the thin film transistor selected for each gate line is turned on by the on / off signal of the gate driving circuit to be scanned, the signal voltage of the data driving circuit becomes the data And the alignment direction of the liquid crystal molecules in the liquid crystal layer is changed by the electric field between the pixel electrode and the common electrode.

In addition, the liquid crystal display device 110 is provided with a backlight unit 120 for supplying light from the backside thereof so that the difference in transmittance represented by the liquid crystal panel 111 is externally expressed.

The backlight unit 120 includes a light guide plate 123, an LED assembly 200 arranged along the longitudinal direction of at least one edge of the light guide plate 123, a white or silver reflection plate 125, And an optical sheet 121.

The LED assembly 200 described above is a light source of the backlight unit 120 and is disposed at one side of the light guide plate 123 so as to face the light incident portion of the light guide plate 123. The LED assembly 200 includes a plurality of LEDs (Hereinafter referred to as " FPCB ") 220, and an LED FPCB (hereinafter, referred to as FPCB) 220 having LEDs 210 spaced apart from each other.

Here, the FPCB 220 of the variable display device 100 according to the embodiment of the present invention has a flexible nature, and a plurality of cutting grooves 230 (see FIG. 3) along both longitudinal side edges thereof are formed at regular intervals And is formed so as to be spaced apart. Accordingly, the LED assembly 200 according to the embodiment of the present invention can prevent the breakage of the FPCB 220 in the mode implementation of the variable display device 100. Let's take a closer look at this later.

The light guide plate 123 spreads evenly over a wide area of the light guide plate 123 to provide a surface light source to the liquid crystal panel 111 as the light incident from the LED 210 travels through the light guide plate 123 by total reflection several times.

The light guide plate 123 may include a pattern of a specific pattern on the back surface to supply a uniform surface light source. Here, the pattern may be formed in various shapes such as an elliptical pattern, a polygon pattern, a hologram pattern, and the like in order to guide 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.

The reflection plate 125 is disposed on the back surface of the light guide plate 123 and reflects light passing through the back surface of the light guide plate 123 toward the liquid crystal panel 111 to improve the brightness and efficiency of light.

The optical sheet 121 on the light guide plate 123 includes a diffusion sheet, at least one light condensing sheet, and the like. Here, the diffusion sheet is positioned directly above the light guide plate 123, and serves to adjust the direction of light so that the light travels toward the light condensing sheet while dispersing the light incident through the light guide plate 123.

The light diffused through the diffusion sheet is condensed in the direction of the liquid crystal panel 111 by the condensing sheet. Thus, almost all the light passing through the light condensing sheet proceeds perpendicularly to the liquid crystal panel 111.

The liquid crystal panel 111 and the backlight unit 120 are integrally modularized through the guide panel 130, the case top 140 and the cover bottom 150 to form the liquid crystal display device 110. The case top 140 Is formed in a rectangular shape whose cross section is bent in a "? &Quot; form so as to cover the upper and side edges of the liquid crystal panel 111 to open an entire surface of the case top 140, .

The guide panel 130 has a rectangular shape for supporting the edges of the liquid crystal panel 111 and covering the edge of the backlight unit 120. The guide panel 130 includes a vertical part surrounding the side surface of the backlight unit 120 and a liquid crystal panel 111 and the backlight unit 120 are distinguished from each other.

This guide panel 130 is seated on the cover bottom 150. The cover bottom 150 provides a horizontal plane on which the backlight unit 120 including the liquid crystal panel 111 is seated, And the edge of the horizontal plane is bent perpendicularly to form the edge of the cover bottom 150.

The guide panel 130 and the cover bottom 150 and the case top 140 are formed so that the edges of the liquid crystal panel 111 and the backlight unit 120 are covered with the guide panel 130, The cover case 140 covering the backside of the backlight unit 120 and the cover bottom 150 covering the backside of the backlight unit 120 are combined at the front and rear sides to be modularly integrated through the guide panel 130. [

In this case, the case top 140 may be referred to as a top cover or a top case, and the guide panel 130 may be referred to as a support main or a main support or a mold frame. The cover bottom 150 may be referred to as a bottom cover or a bottom cover I will.

At this time, the liquid crystal display device 110 having the above-described structure can eliminate the case top 140 and the cover bottom 150 in order to realize a lightweight and thin liquid crystal display device which is recently required. It is possible to reduce the weight and thickness of the liquid crystal display device 110 by eliminating the case top 140 and the cover bottom 150, thereby simplifying the process.

In addition, the elimination of the case top 140 and the cover bottom 150, which are made of a metal material, can reduce the process cost.

The modularized liquid crystal display device 110 is finally modularized through the front cover 160 and the rear cover 170 to form the variable display device 100.

As shown in FIG. 1A, the variable display device 100 according to the embodiment of the present invention allows the liquid crystal display device 110, in which an image is implemented, to operate in a flat mode, which is a flat plate type, A liquid crystal display device 110 in which an image is implemented as shown in FIG. 1B may be formed in a concave curved mode having a curved surface portion concavely curved with respect to the front of the liquid crystal display device 110 concave curved mode), the viewer can further improve the immersion level and the image can be made more realistic, thereby making the user feel comfortable.

1C, the liquid crystal display device 110 in which an image is implemented may be referred to as a convex curved mode having a convexly curved surface with respect to the front of the liquid crystal display device 110 And thus has a large viewing radius, and transmits contents such as news, advertisements, and the like to an image realized by the liquid crystal panel 110 to a large number of viewers.

That is, the variable display device 100 of the present invention can be selectively changed to a flat plate mode, a convex curved surface mode, or a concave curved mode, so that the user can select a flat mode and a curved mode display It can be used as a device, and convenience of the user can be considered.

In particular, the variable display device 100 according to the embodiment of the present invention can be realized by mounting a plurality of LEDs 210 of the LED assembly 200, which is a light source of the backlight unit 120 of the liquid crystal display device 110, The variable display device 100 can be manufactured by mounting a plurality of cutting grooves 230 (see FIG. 3) at predetermined intervals along both longitudinal edges of the FPCB 220, The convex curved surface mode, the concave curved surface mode, and the flat plate type mode, it is possible to prevent the stress from being concentrated on the FPCB 220, thereby preventing the FPCB 220 from being damaged.

This can prevent the problem of lowering the luminance of the variable display device 100 and prevent a problem that the quality of the variable display device 100 such as luminance and image quality is lowered .

FIG. 3 is a perspective view schematically showing an LED assembly of a liquid crystal display of a variable display device according to an embodiment of the present invention, and FIGS. 4a to 4b are plan views schematically showing deflection of the LED assembly of FIG. 3a.

3, the LED assembly 200 includes a plurality of LEDs 210, a plurality of FPCBs 220 mounted on the LEDs 210 by a surface mount technology (SMT) ).

The LED assembly 200 is fixed to the inside of the edge portion of the cover bottom (150 in FIG. 2) using a screw (not shown) or fixed via an adhesive tape (not shown) or a fixing clip And the light emitted from the plurality of LEDs 210 faces the light incident surface of the light guide plate 123 (see FIG. 2).

At this time, when using a fixing clip (not shown), grooves for fixing clips (not shown) may be provided along both side edges of the FPCB 220.

The plurality of LEDs 210 emit light having colors of red (R), green (G), and blue (B), respectively. By lighting the plurality of RGB LEDs 210 at once, have.

Alternatively, the LEDs 210 may be configured to emit white light in each of the LEDs 210 by using the LEDs 210 constituted by LED chips (not shown) emitting all the colors of RGB, So that each of them can realize a complete white light.

In this case, the plurality of LEDs 210 use a blue LED 210 including a blue LED chip having excellent luminous efficiency and luminance for improving luminous efficiency and luminance, and use a cerium-doped yttrium aluminum garnet (YAG : Ce) ', that is, a blue LED 210 made of a yellow phosphor may be used.

The blue light emitted from the blue LED 210 is mixed with the yellow light emitted by the phosphor through the phosphor, thereby realizing the white light.

Here, the FPCB 220 is composed of a base film having a flexible characteristic, a power wiring layer formed of a plurality of metal wirings formed by patterning a conductive material on the base film, and a cover layer.

The base film serves to support a power wiring layer and a plurality of LEDs 210 as an upper layer thereof.

Such a base film is made of a film-like material containing a resin-based material including polyimide or polyester. Alternatively, it may be made of a material having thermal conductivity such as FR4 (flame resistant 4) and T-preg.

A cover layer is formed as an organic or inorganic insulating material for protecting the power wiring layer, except for a portion where a large number of metal wirings are formed in the upper portion of the power wiring layer.

The plurality of LEDs 210 mounted on the FPCB 220 are connected in series or in parallel through the metal wiring of the power wiring layer to receive power.

Here, the LED assembly 200 according to the embodiment of the present invention is formed with a plurality of cutting grooves 230 spaced apart from each other at both side edges along the longitudinal direction of the FPCB 220.

The plurality of cut grooves 230 are formed of first and second inclined surfaces 230a and 230b inclined at predetermined angles. The plurality of cut grooves 230 are formed along both longitudinal edges of the FPCB 220 The FPCB 220 is disposed in the longitudinal direction of the FPCB 220 such that the vertex of the first and second sloping faces 230a and 230b faces the vertex of the first and second sloping faces 230a and 230b of the cut groove 230 formed at the opposite edge, As shown in FIG.

The sum of the distances d between the first and second sloping faces 230a and 230b of the plurality of cut grooves 230 formed along one side edge of the FPCB 220 is formed along the following formula However,

[Equation 1]

Where n is a constant, n is the number of cutting grooves 230 formed along one edge of the FPCB 220 and d is the distance d between the first and second sloping faces 230a and 230b of the cutting groove 230 ).

The distance d between the first and second inclined surfaces 230a and 230b of the plurality of cutting grooves 230 can be defined according to the following equation.

[Equation 2]

Here, W represents the width of the FPCB 230.

Then, R _? Is defined by the following equation (3), where R in equation (3) represents the radius of a circle based on the center of the FPCB 220 in which the deflection is generated.

[Equation 3]

이므로,

이다. For example, when the FPCB 220 having a length of 1205 mm and a width of 10 mm is to be warped by 5000 R,

Because of,

to be.

이고,

이므로, And,

ego,

Because of,

가 된다.

.

That is, in order to generate flexure of the FPCB 220 so as to have 5000 R when the length of the FPCB 220 is 1205 mm and the width W is 10 mm, a plurality of cutting grooves (not shown) formed along one edge of the FPCB 220 The sum of the distances d between the first and second inclined surfaces 230a and 230b of the first and second sloping surfaces 230 and 230 is 1.205 mm or more.

Accordingly, the LED assembly 200 can be mounted on the FPCB 220 in a direction parallel to the plane of the FPCB 220, that is, in a direction in which the plurality of LEDs 210 of the FPCB 220 are mounted, through the cutting groove 230, The deflection of the FPCB 220 can be realized in a direction perpendicular to the normal of the mounting surface with respect to the scene (+ X and -X axis directions defined in the drawing).

The LED assembly 200 according to the present invention can prevent the stress from being applied to the FPCB 220 of the LED assembly 200 during the process of changing the variable display device 100 of FIG. 2 into the planar mode and the concave or convex curved mode. It is possible to prevent the FPCB 220 from being damaged.

That is, as shown in FIG. 4A, the LED assembly 200 may generate warpage in the + X axis direction defined by both ends in the longitudinal direction of the FPCB 220 in a plan view. In this case, the FPCB 220 may be a FPCB Both side edges in the longitudinal direction of the base plate 220 are concave toward the + X axis direction.

The distance d between the first and second sloping faces 230a and 230b of the plurality of cutting grooves 230 without warping is defined as the first distance. The first and second sloping faces 230a and 230b of the plurality of cutting grooves 230 formed along the first edge 220a facing the + X axis direction of the FPCB 220 are formed to be concave toward the + X axis direction, 230b are reduced to a second spacing d1 that is narrower than the first spacing d.

The gap between the first and second sloping faces 230a and 230b of the plurality of cutting grooves 230 formed along the second edge 220b facing the? -Axis direction of the FPCB 220 is greater than the first distance d. (D2) larger than the second gap (d2).

That is, the FPCB 220 is formed such that the radius of curvature of the first edge 220a is narrower than the radius of curvature of the second edge 220b, and the FPCB 220 is arranged so that both side edges in the longitudinal direction of the FPCB 220 are + X So that warpage can be generated concavely toward the axial direction.

4B, when both ends in the longitudinal direction of the FPCB 220 generate warp toward the? -Axis direction defined in the figure, the FPCB 220 is positioned on both side edges in the longitudinal direction of the FPCB 220 Is formed to be convex toward the + X-axis direction.

The interval between the first and second slopes 230a and 230b of the plurality of cut grooves 230 formed along the first edge 220a of the FPCB 220 facing the + Of the plurality of cut grooves 230 formed along the second edge 220b facing the? Axis direction of the FPCB 220 and the first and second sloping faces 230a , 230b are formed to have a fifth interval (d4) narrower than the first interval (d).

The FPCB 220 is formed such that the radius of curvature of the first edge 220a is wider than the radius of curvature of the second edge 220b so that both side edges in the longitudinal direction of the FPCB 220 are positioned at + It is possible to generate warpage convex toward the axial direction.

As described above, the FPCB 220 of the LED assembly 200 according to the embodiment of the present invention includes a plurality of cut grooves 230 formed along the longitudinal direction along with the flexible nature of the FPCB 220, It is possible to realize the bending of the FPCB 220 in a direction perpendicular to the normal line of the mounting surface around the mounting surface where the LEDs 210 are mounted so that the variable display device 100 of FIG. The stress is not concentrated on the FPCB 220 of the LED assembly 200, and damage to the FPCB 220 can be prevented.

2) of the liquid crystal display device (110 in FIG. 2) is bent in the direction of the front of the liquid crystal display device (110 in FIG. 2) in a flat plate- The FPCB 220 of the LED assembly 200 is warped such that the radius of curvature of one edge toward the liquid crystal panel (111 of FIG. 2) becomes narrower than the radius of curvature of the opposite edge of the FPCB 220 .

2) is changed to a convex curved surface mode having a convexly curved surface with respect to the front of the liquid crystal display device 110 (see FIG. 2) The FPCB 220 of FIG. 3B is bent such that the radius of curvature of one edge of the liquid crystal panel (111 in FIG. 2) is wider than the radius of curvature of the opposite edge.

At this time, even if bending of the FPCB 220 occurs, the stress due to the bending is not concentrated on the FPCB 220, and the breakage of the FPCB 220 can be prevented.

That is, in a general LED assembly, a stress is concentrated at both side edges of the FPCB in a process in which the variable display device is changed from the planar mode to the concave or convex curved mode, and the FPCB phenomenon occurs due to such stress .

This phenomenon of the FPCB causes damage to the FPCB or changes the optical distance between the LEDs mounted on the FPCB and the light guide plate incident surface, thereby lowering the luminance of the variable display device.

This deteriorates the quality of the variable display device such as luminance and image quality degradation.

In contrast, the LED assembly 200 according to the embodiment of the present invention forms a plurality of cut grooves 230 along both longitudinal edges of the FPCB 220, so that the variable display device 100 (see FIG. 2) The stress concentrated on both side edges of the FPCB 220 is canceled by the cutting grooves 230 so that the stress is not concentrated.

2) mounted on the FPCB 220 and the plurality of LEDs 210 mounted on the FPCB 220 are prevented from being damaged by the FPCB 220, The optical distance between the light-entering surfaces is also not changed, so that the luminance of the variable display device (100 in Fig. 2) is not lowered.

Therefore, the variable display device (100 of FIG. 2) according to the embodiment of the present invention is improved in luminance and picture quality.

2) of the FPCB 220 of the LED assembly 200, which is the light source of the liquid crystal display (110 of FIG. 2), is disposed on both side edges in the longitudinal direction of the FPCB 220 (100 in FIG. 2) can be changed into a convex curved surface mode, a concave curved surface mode, and a flat plate mode by forming a plurality of cut grooves 230 along the longitudinal direction of the FPCB 220 It is possible to prevent the breakage of the FPCB 220 from occurring.

Thus, it is possible to prevent the problem of lowering the luminance of the variable display device (100 of FIG. 2), and the quality of the variable display device (100 of FIG. 2) such as luminance and image quality deteriorates Can be prevented.

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

200: LED assembly
210: LED
220: FPCB
230: cutting grooves 230a and 230b (first and second inclined surfaces)

Claims (8)

A liquid crystal panel;
A light guide plate positioned below the liquid crystal panel;
And a flexible printed circuit board (FPCB) disposed corresponding to the light incident surface of the light guide plate and having a plurality of LEDs, a plurality of LEDs, and a plurality of cut grooves spaced along both side edges in the longitudinal direction, LED assembly
Wherein the FPCB is bent in a direction perpendicular to a normal of a mounting surface where the plurality of LEDs are mounted.
The method according to claim 1,
The liquid crystal panel and the LED assembly may be formed in a flat mode, a convex curved mode or a concave curved mode, which forms a convex or concave curved surface, .
The method according to claim 1,
Wherein the plurality of cut grooves are formed of first and second sloped surfaces, and the vertexes of the plurality of cut grooves provided at the first edge in the longitudinal direction of the FPCB are cut in a plurality of cuts provided at the second edge in the longitudinal direction of the FPCB, Wherein the vertexes of the grooves face each other.
The method of claim 3,
The sum of the intervals between the first and second inclined surfaces of the plurality of cut grooves

(N is a constant, n is the number of the cut groove formed along the one edge of the FPCB, d is the spacing between the first and second inclined surfaces, W is the width of the FPCB, _θ R is

(Where R is the radius of a circle with respect to the central portion of the FPCB where the warp occurred)).
The method of claim 3,
When the variable display device is in the convex curved mode,
And the FPCB is bent so that both side edges of the FPCB are convex toward the liquid crystal panel.
6. The method of claim 5,
Wherein a distance between the first and second slopes of the plurality of cut grooves provided at the first edge of the FPCB facing the liquid crystal panel is greater than a distance between the first and second slits of the plurality of cut grooves provided at the second edge And the interval between the two inclined surfaces.
The method of claim 3,
When the variable display device is in the concave curved mode,
Wherein the FPCB is bent so that both side edges thereof are concave toward the liquid crystal panel.
8. The method of claim 7,
Wherein a distance between the first and second slopes of the plurality of cut grooves provided at the first edge of the FPCB facing the liquid crystal panel is greater than a distance between the first and second slits of the plurality of cut grooves provided at the second edge 2 is smaller than the interval between the two inclined surfaces.

Images