KR20030082828A - Light guiding panel, backlight assembly, and liquid crystal display having thereof - Google Patents

Abstract

PURPOSE: A light guide, a back light assembly and a liquid crystal display including the light guide and back light assembly are provided to prevent light leakage even if a separate light-shielding printed pattern for preventing light leakage is not formed on a diffusion plate. CONSTITUTION: A light guide includes a light receiving part(111) with the first height(T1) that is located in close proximity to a lamp and receives lights generated by the lamp, a part(112) that is opposite to the light receiving part and has the second height(T2) lower than the first height, and the first bottom part(113) extended from the bottom edge of the light receiving part by the first length(L1). The light guide further includes the second bottom part(114) extended from the bottom edge of the first bottom part to the bottom edge of the opposite part by the second length(L2), and a top face(115) placed in parallel with the first bottom part and extended from the top edge of the light receiving part to the top edge of the opposite part by the third length(L3). The top face projects guided lights.

Description

LIGHT GUIDING PANEL, BACKLIGHT ASSEMBLY, AND LIQUID CRYSTAL DISPLAY HAVING THEREOF}

The present invention relates to a light guide plate, a backlight assembly, and a liquid crystal display device having the same, and more particularly, to a wedge type light guide plate having a flat surface, a backlight assembly including the same, and a liquid crystal display device having the same.

Recently, information processing devices have been rapidly developed to have various forms, various functions, and faster information processing speed. Information having an electrical signal form processed by such an information processing device requires a display device serving as an interface.

Recently, various flat panel display devices have been developed in comparison with CRT display devices, which are lightweight, compact, and have a function such as full-color and high resolution.

Generally, a liquid crystal display device, which is a leader of a flat panel display device, applies a voltage to a specific molecular array of a liquid crystal and converts it into another molecular array. A display device that displays an image by converting changes in optical properties such as chromaticity and light scattering characteristics into visual changes.

Since the liquid crystal display (LCD) does not self-luminous, it displays information by reflecting extraneous light that has passed through the LCD panel, or displays an information by installing a separate light source, that is, a backlight assembly, on the back of the LCD panel.

The backlight assembly may include a lamp unit for emitting light, a light guide plate (or light guide plate) for guiding light emitted from the lamp unit toward the LCD panel, a reflector (or reflector) for reflecting light leaked to the light guide plate at a lower portion of the light guide plate, and a light guide plate. It comprises an optical sheet to increase the brightness of the light transmitted from.

In general, the light guide plate of the backlight unit is classified into a flat type having a lamp unit provided at both sides and a wedge type provided at one side of the lamp unit according to the arrangement position of the lamp unit.

1 is a view for explaining a general flat light guide plate.

Referring to FIG. 1, light is emitted from lamp units 14a and 14b provided inside lamp storage containers (or lamp reflectors) 12a and 12b that block light leakage on both sides of a flat light guide plate 10. It receives the guide to the diffusion sheet (16) side. In this case, a separate reflecting plate 18 is provided to re-reflect light leaking to the lower portion of the light guide plate 12.

The light guide plate (or light guide plate) included in the current backlight assembly has a high density because it is made of a polymer material such as polymethyl methacrylate (PMMA) or cyclic olefin polymer (COP). Accordingly, it takes the largest weight among the various components constituting the LCD module. In particular, in a liquid crystal display device in which weight or thickness factors are important, such as a notebook computer, a wedge type light guide plate, which is lighter than a flat type, may be used.

2 illustrates a general wedge type light guide plate.

Referring to FIG. 2, one side of the wedge-type light guide plate 20 receives and diffuses light from a lamp unit 24 provided inside the lamp accommodating container (or lamp reflector) 22 that blocks light leakage. The sheet 26 is guided to the side. In this case, a separate reflector 28 is provided to re-reflect the light leaking to the lower portion of the light guide plate 20.

However, as shown in FIG. 3, the backlight assembly having the wedge-type light guide plate is a part of the diffusion sheet 26 provided on the top of the light guide plate 20 having a wedge shape, that is, the lamp reflector 22. There is a problem in that a separate print pattern 27 for blocking the leakage light in the area having a predetermined width set along the.

This is because, among the light emitted from the lamp 24 and reflected on the lower side of the light guide plate 20, the light (1, 2), which is reflected by the lamp 24, is reflected along the normal light path, but the lamp 24 Since the light (3, 4) reflected close to the side acts as leakage light, the printing pattern 27 is used as a kind of light shielding film for blocking such leakage light.

On the other hand, the lamp storage container used when fixing the lamp for supplying light to the wedge-type light guide plate is irrelevant when coupled to the upper side of the light guide plate in units of planes, but the coupling surface with the lower side of the light guide plate is one line There is a problem that the fastening force is weak because it is combined in units.

In particular, when the flow is severe, such as a notebook computer, the wedge-type light guide plate having a weak fastening force is severely adversely affected by the liquid crystal panel which is separated from the lamp storage container and disposed on the lamp or the upper side stored in the lamp storage container.

Accordingly, the technical and problem of the present invention are to solve such a conventional problem, and an object of the present invention is to provide a light blocking pattern in a predetermined region of a diffusion sheet disposed on the upper surface by forming a lower surface in parallel with the upper surface. If not, and to provide a wedge-type light guide plate having some flat surface that can enhance the fastening force with the lamp housing.

In addition, another object of the present invention to provide a backlight assembly having the light guide plate described above.

Another object of the present invention is to provide a liquid crystal display device having the above-described backlight assembly.

1 is a view for explaining a general flat light guide plate.

2 illustrates a general wedge type light guide plate.

3 is an enlarged view of a portion of FIG. 2 described above.

4 is a view for explaining a light guide plate according to an exemplary embodiment of the present invention.

FIG. 5A is a view for explaining an example of a lamp storage container suitable for use in the light guide plate of FIG. 4, and FIG. 5B is a view for explaining another example of a lamp storage container suitable for adoption in the light guide plate of FIG. 4. Drawing.

6 is a cutaway view of a part of a backlight assembly employing a light guide plate according to the present invention.

7 is a view for explaining a mold frame for housing the backlight assembly according to the present invention.

8 is a perspective view illustrating a liquid crystal display device according to the present invention.

<Description of Symbols for Main Parts of Drawings>

10, 20, 110: light guide plate 12a, 12b, 22, 120: lamp storage container

14a, 14b, 24, 130: lamp unit 100: backlight assembly

200: mold frame 232, 242: rib

300: display unit 400: rear case

500: top chassis 600: front case

A light guide plate according to one aspect for realizing the object of the present invention is a light guide plate that guides a path of light provided from a lamp and emits guided light, the light guide plate being closest to the lamp and having a first height. A light receiving unit configured to receive light provided from a lamp; An opposite part facing the light incident part having a second height lower than the first height; A first bottom portion extending from the lower end side of the light incident portion by a first length; A second bottom portion extending from the end edge of the first bottom portion to the bottom end edge of the opposite portion by a second length; And an upper surface that is parallel to the first bottom portion, extends by a third length from an upper end edge of the light incident portion to an upper end edge of the opposing portion, and emits the guided light.

In addition, a backlight assembly according to one aspect for realizing another object of the present invention includes a lamp for generating light; A light guide plate for guiding the light provided through the light incidence part and outputting the light through the light incidence part, and a part of the bottom part of the bottom part opposite to the light incidence part adjacent to the light incidence part has a flat surface parallel to a direction in which the light incidence part is formed; And a lamp accommodating container accommodating the lamp through coupling with the light guide plate.

In addition, a liquid crystal display device according to one feature for realizing another object of the present invention described above comprises: a first storage container having four sidewalls and a bottom surface; A second accommodating container having four sidewalls and a partially opened bottom part, the second accommodating container accommodated in the first accommodating container; A lamp for generating light and light provided through the light incidence part are guided and output through the light incidence part, and a part of the bottom part adjacent to the light incidence part among the bottom parts facing the light incidence part is parallel to the direction in which the light incidence part is formed. A back light assembly having a light guide plate having a flat surface, and a lamp accommodating container accommodating the lamp and blocking leakage of the light through coupling with the light guide plate; A liquid crystal display unit including a liquid crystal layer between the lower substrate and the upper substrate, and displaying an image in response to light provided from the backlight assembly; A third accommodating container which protrudes inwardly from the top of the four sidewalls and the sidewalls to form an opening, and exposes an upper substrate of the liquid crystal display unit through the formed opening; And a fourth accommodating container accommodating the second accommodating container, the backlight assembly, the liquid crystal display unit, and the third accommodating container through coupling with the first accommodating container.

According to such a light guide plate, a backlight assembly having the same, and a liquid crystal display device having the same, not only the light leakage phenomenon of the light incident part may be prevented in the light guide plate requiring high brightness, but also a defect due to the flow of the light guide plate may be prevented.

Hereinafter, with reference to the accompanying drawings, it will be described in detail the present invention.

4 is a view for explaining a light guide plate according to an exemplary embodiment of the present invention.

Referring to FIG. 4, the light guide plate 110 according to the embodiment of the present invention includes a light incident part 111, an opposing part 112, a first bottom part 113, a second bottom part 114, and an upper surface 115. ), Having a seven-sided shape consisting of a first side surface 116 and a second side surface 117, receives the light provided from the lamp through the light incident part to guide the optical path, and guides the guided light to the upper surface ( Exit through 115).

The light incident part 111 is close to a lamp (not shown), and has a first height T1 to serve as a light incident part for receiving light provided from the lamp.

The opposite part 112 has a second height T2 lower than the first height T1 and faces the light incident part 111.

The first bottom portion 113 extends by the first length L1 from the lower end side of the light incident portion 111. Of course, it is preferable that the first bottom portion 113 forms a right angle with the light incident portion 111, but the present invention is not limited thereto, and may have an acute angle smaller than a right angle or an obtuse angle larger than a right angle.

The second bottom portion 114 extends from the longitudinal edge of the first bottom portion 113 and extends to the lower longitudinal edge of the opposing portion 112 in the positive (+) direction rather than in the forming direction of the first bottom portion 113. It extends by the second length (L2) to guide the path of the light provided through the light incident portion 111 toward the emission area side. Here, the positive direction refers to the + Y axis direction when the formation line of the first bottom part is viewed in the X axis, whereas the negative direction refers to the -Y axis direction, and the second It is preferable that length L2 is larger than 1st length L1.

The upper surface 115 is provided with an emission area and a non-emission area on the same plane as the emission area so as to have a third length L3 from an upper end side of the light incident part 111 to an upper end side of the opposing part 112. It extends by), and serves as a light emitting unit for emitting guided light. Here, the emission area is an active area substantially corresponding to the display operation, and the non-emission area is an area independent of the display operation. In addition, the upper surface 115 is preferably parallel to the first bottom portion 113, the third length (L3) is the height of the triangle (that is, a large height) and the second length L2 as the slope It is preferable that it is the sum of 1 length L1.

The first side surface 116 has a pentagonal shape consisting of first to fifth ends, in particular, the first end side is in contact with the first end side of the light incident part 111, and the second end side is opposite to the opposite side ( 112, the third end is in contact with the end of the first bottom 113, the fourth end is in contact with the end of the second bottom 114, the fifth end Is in contact with the longitudinal side of the upper surface (115).

The second side surface 117 has a pentagonal shape consisting of first to fifth end sides, in particular, the first end side is in contact with the second end side of the light incident part 111, and the second end side is formed at the opposite side. The second end side is in contact with the third end side, and the third end side is in contact with the end side of the first bottom portion, the fourth end side is in contact with the end side of the second bottom portion, and the fifth end side is in contact with the end side of the upper surface.

FIG. 5A is a view for explaining an example of a lamp storage container suitable for use in the light guide plate of FIG. 4, and FIG. 5B is a view for explaining another example of a lamp storage container suitable for adoption in the light guide plate of FIG. 4. Drawing.

4 and 5A, the lamp accommodating container 120a, which is optimal for the light guide plate 110 according to the present invention, includes a side member 112a having a curved surface and a side member so as to contact an upper surface of the light guide plate 110. The first coupling member 124a extending by the fourth length L4 from one side of the outermost side of 112a and the other side of the outermost side of the side member 112a so as to contact the flat surface of the light guide plate 110. The second coupling member 126a extends by the fifth length L5 larger than the fourth length L4.

4 and 5B, the lamp accommodating container 120b, which is optimal for the light guide plate 110 according to the present invention, has a side member 122b having a curved surface and a side in contact with an upper surface of the light guide plate 110. The first coupling member 124b extending from the one side of the member 122b by the fourth length L4 and the fourth length L4 from the other side of the side member 122b so as to contact the flat surface of the light guide plate 110. The second coupling member 126b extends by a large fifth length L5.

6 is a cutaway view of a part of a backlight assembly employing a light guide plate according to the present invention.

4 to 6, the backlight assembly 100 according to the present invention includes a light guide plate 110, a lamp accommodating container 120 provided at a side of the light guide plate, and a lamp 130 accommodated in the lamp accommodating container 120. ), A reflecting plate 140 provided below the light guide plate 110, and a diffusion plate 150 provided on the light guide plate 110, and supported by the mold frame 200, and provided on the upper side of the light guide plate 110. The light for the display is provided on the display panel (not shown) side.

The light guide plate 110 guides the light provided through the light incidence part, that is, the light in the light incidence part 111, and outputs the light through the light exit part provided in the upper part, that is, the upper surface 115. A portion 113 of the bottom portion adjacent to the light incident portion 111 of the bottom portion opposite to the flat portion has a flat surface extending parallel to the formation direction of the light exit portion 115.

The lamp accommodating container 120 accommodates a lamp 130 that generates light and blocks light leakage through coupling with the light guide plate 110. In this case, the lamp accommodating container 120 coupled to the light guide plate 110 is a kind of clip type having side members 122a and 122b and first and second coupling members 124a, 126a, 124b, and 126b. The length L6 of the first coupling member overlapping the upper surface of the second coupling member overlapping with the bottom of the light guide plate 110 is preferably smaller than the length L1 of the second coupling member overlapping the bottom surface of the light guide plate 110.

For example, in the case of the backlight assembly employed in the 15-inch model liquid crystal display panel, the length L6 of the first coupling member overlapping the upper surface of the light guide plate is 0.8 mm and overlaps the lower surface of the light guide plate 110. The length L1 of the second coupling member is preferably 7.0 to 10.0 mm. Here, the upper limit of 10.0 mm is the rib described above when the thickness of the rib RIB drawn from the mold frame 200 supporting the backlight assembly 100 is disposed at the rear surface of the backlight assembly 100 to be 0.5 mm. It is the dimension considering thickness.

In addition, in the case of a backlight assembly employing a conventional wedge-type light guide plate, as shown in FIG. 3, the seventh length L7 is disposed close to a predetermined region of the diffuser plate disposed above the light guide plate, that is, the lamp. In order to block the light leaking through the said area | region to the width | variety made into the width | variety, a kind of light shielding pattern was provided.

However, in the backlight assembly according to the present invention, since the structure of the light guide plate does not cause leakage light, the diffuser plate provided on the light guide plate does not need to have a separate light shielding pattern.

In addition, in the case of a backlight assembly employing a conventional wedge type light guide plate, as shown in FIG. 3, the upper surface of the light guide plate coupled to the lamp storage container is coupled through surface contact, but the lower surface of the light guide plate is wired. There is a problem that the fastening force is weak because it is coupled through the contact.

However, in the backlight assembly according to the present invention, when the structure of the light guide plate is coupled to the lamp storage container, both the upper surface and the lower surface may be coupled through surface contact, thereby enhancing tightening force.

7 is a view for explaining a mold frame for housing the backlight assembly according to the present invention.

Referring to FIG. 7, the mold frame 200 for accommodating the backlight assembly according to the present invention has a box shape of a rectangular parallelepiped, an upper surface of which is opened in front, and a portion of the lower portion of which is opened, thereby allowing the backlight to be opened through the upper surface of the upper surface. The assembly 100 is received.

The mold frame 200 may include a first sidewall 210 corresponding to the lamp of the backlight assembly 100, a second sidewall parallel to a direction in which the first sidewall 210 is formed, and opposite to the first sidewall 210. 220, a third sidewall 230 connecting one end of the first sidewall 210 and one end of the second sidewall 220, connecting the other end of the first sidewall 210 and the other end of the second sidewall 220. The fourth side wall 240 is formed.

In more detail, the first sidewall 210 has a front opening as well as a bottom surface to correspond to the lamp of the backlight assembly 100.

The second sidewall 220 is provided on the side opposite to the first sidewall 210 and accommodates a wedge-shaped light guide plate provided in the backlight assembly 100. In this case, the thickness of the light guide plate accommodated in the second side wall 220 is thinner than the thickness of the light guide plate disposed to correspond to the first side wall 210. can do.

The third side wall 230 and the fourth side wall 240 may include a predetermined protruding member (rib; RIB) 232 and 242 which protrude inwardly from a predetermined area of the lower surface to accommodate the backlight assembly 100. . In particular, the ribs 232 and 242 protruding from the third side wall 230 and the fourth side wall 240 do not protrude from the entire lower surface of the side wall, and have a flat surface as shown in FIG. 7. It is preferable to partially protrude in view of the thickness of.

That is, the rib 232 of the third sidewall and the rib 242 of the fourth sidewall 240 respectively connected to the first sidewall 210 may be separated from the first sidewall 210 by a predetermined length L5. It is preferably formed.

8 is a perspective view illustrating a liquid crystal display device according to the present invention.

Referring to FIG. 8, the liquid crystal display according to the present invention includes a backlight assembly 100, a mold frame 200, a display unit 300, a rear case 400, a top chassis 500, and a front that generate light. And a case 600.

The backlight assembly 100 may uniform the luminance of the light emitted from the lamp unit 130 for generating light, the light guide plate 110 for changing the path of the light while guiding the light toward the display unit 300, and the light guide plate 110. Mold including the optical sheet 150 and the reflector plate 140 for reflecting light leaking from the light guide plate 110 under the light guide plate 110 to the light guide plate 110 to increase the efficiency of light. It is stored in the frame 200. Since the backlight assembly 100 has been described in detail with reference to FIGS. 4 to 6, a detailed description thereof will be omitted.

As is known, the display unit 300 is disposed above the backlight assembly 100 to display a screen by light emitted from the backlight assembly 100. In this case, the display unit 300 includes a liquid crystal display panel 311, gate and data PCBs 312 and 313, and gate and data tape carrier packages 314 and 315.

As is known, the rear case 400 accommodates the mold frame 200 for accommodating the backlight assembly 100 and the display unit 300 through fastening with the front case 600, and the top chassis 500 is The front case 600 is disposed between the display unit 300.

As described above, by changing the structure of the backlight assembly employed in the liquid crystal display device or the light guide plate employed in the backlight assembly to a structure for strengthening the fastening force, even if the liquid crystal display device moves frequently, The adverse effect can be minimized.

In addition, since light leakage from the light incident part of the lamp can be prevented in the diffuser plate employed in the backlight assembly, a process of forming a separate light-shielding printing pattern to prevent light leakage is unnecessary, thereby reducing the man-hour. have.

Although described above with reference to the embodiments, those skilled in the art can be variously modified and changed within the scope of the present invention without departing from the spirit and scope of the invention described in the claims below. I can understand.

As described above, according to the present invention, a partial shading printing pattern for preventing light leakage is formed by forming a portion of the bottom of the wedge type light guide plate facing the light exit portion in a flat type parallel to the light exit portion formation direction. The light leakage phenomenon can be prevented even if not formed in the diffusion plate.

In addition, since the lamp receiving container fastened to the surface of the light guide plate is fastened through surface contact not only to the upper surface but also to the lower surface of the light guide plate, the fastening force may be improved.

Claims (9)

A light guide plate for guiding a path of light provided from a lamp and emitting guided light, A light incident part close to the lamp and receiving light provided from the lamp at a first height; An opposite part facing the light incident part having a second height lower than the first height; A first bottom portion extending from the lower end side of the light incident portion by a first length; A second bottom portion extending from the end edge of the first bottom portion to the bottom end edge of the opposite portion by a second length; And And a top surface parallel to the first bottom portion, extending from the upper end edge of the light incident portion to the upper end edge of the opposing portion by a third length, and emitting the guided light. The light guide plate of claim 1, wherein the first length is smaller than the second length. The light guide plate according to claim 1, wherein the third length is a sum of a large height of a triangle having the second length as a slope and the first length. A lamp for generating light; A light guide plate for guiding the light provided through the light incidence part and outputting the light through the light incidence part, and a part of the bottom part of the bottom part opposite to the light incidence part adjacent to the light incidence part has a flat surface parallel to a direction in which the light incidence part is formed; And And a lamp accommodating container accommodating the lamp through coupling with the light guide plate. The method of claim 4, wherein the light guide plate, A light incident part close to the lamp and receiving light provided from the lamp at a first height; An opposite part facing the light incident part having a second height lower than the first height; A first bottom portion extending from the lower end side of the light incident portion by a first length; A second bottom portion extending from the end edge of the first bottom portion to the bottom end edge of the opposite portion by a second length; And And a top surface parallel to the first bottom portion and extending by a third length from an upper end edge of the light incident portion to an upper end edge of the opposing portion, the upper surface emitting the guided light. . The method of claim 4, wherein the lamp storage container, Side members; A first coupling member extending from a side of the side member by a first length so as to contact an upper surface of the light guide plate; And And a second coupling member extending from the other side of the side member by a second length so as to be in contact with the flat surface of the light guide plate. The backlight assembly of claim 6, wherein the second coupling member of the lamp housing is coupled to the flat surface of the light guide plate through surface contact. A first storage container having four side walls and a bottom surface; A second accommodating container having four sidewalls and a partially opened bottom part, the second accommodating container accommodated in the first accommodating container; A lamp for generating light and light provided through the light incidence part are guided and output through the light incidence part, and a part of the bottom part adjacent to the light incidence part among the bottom parts facing the light incidence part is parallel to the direction in which the light incidence part is formed. A back light assembly having a light guide plate having a flat surface, and a lamp accommodating container accommodating the lamp and blocking leakage of the light through coupling with the light guide plate; A liquid crystal display unit including a liquid crystal layer between the lower substrate and the upper substrate, and displaying an image in response to light provided from the backlight assembly; A third accommodating container which protrudes inwardly from the top of the four sidewalls and the sidewalls to form an opening, and exposes an upper substrate of the liquid crystal display unit through the formed opening; And And a fourth storage container configured to accommodate the second storage container, the backlight assembly, the liquid crystal display unit, and the third storage container through coupling with the first storage container. The liquid crystal display of claim 8, wherein a bottom portion of the second storage container defines an opening degree through a plurality of ribs protruding inwardly, and the opening degree of the rib is adapted to a flat surface of the light guide plate. .