KR102573441B1 - Liquid crystal display device - Google Patents

Abstract

A liquid crystal display device according to the present invention includes a liquid crystal display panel, a backlight unit disposed on the rear surface of the liquid crystal display panel, and a case member accommodating the liquid crystal display panel and the backlight unit therein. The case member includes a guide panel and a case top. The guide panel includes a panel support and an extension. The panel support part is provided between the liquid crystal display panel and the backlight unit to support an edge of the liquid crystal display panel from a lower portion. The extension part extends from the panel support part and wraps around the side surface of the backlight unit. The case top includes a horizontal portion and a vertical portion. The horizontal part surrounds the front edge of the liquid crystal display panel. The vertical portion extends from the horizontal portion and surrounds the extension of the guide panel from the outside. At least one of the extension part and the vertical part includes a forming part protruding between the extension part and the vertical part.

Description

Liquid crystal display {LIQUID CRYSTAL DISPLAY DEVICE}

The present invention relates to a liquid crystal display device including a backlight unit.

Liquid crystal display devices are used as display devices in various fields such as portable computers such as notebook PCs, office automation devices, audio/video devices, indoor and outdoor advertising displays, and vehicle displays. The liquid crystal display may be divided into a reflective type, a transflective type, a transmissive type, and the like. A transflective or transmissive liquid crystal display displays an image by controlling an electric field applied to a liquid crystal layer to adjust light incident from a back light unit (BLU) according to a data voltage.

Fluorescent lamps such as Cold Cathode Fluorescent Lamps (CCFLs) have been used as light sources for backlight units, but recently, light emitting diodes (hereinafter referred to as 'LEDs') are mainly used compared to conventional fluorescent lamps. It is becoming.

In-vehicle displays are getting larger in size and the quantity installed per vehicle is also increasing. In-vehicle displays are being applied as driving support interfaces in addition to navigation. Vehicle displays are expanding their application range to instrument panels, driver warnings, and display means for driving assistance. In addition, liquid crystal displays are also being applied to Head-Up Display (HUD) devices that project vehicle speed, remaining fuel, and navigation information as graphic images on the windshield right in front of the driver. A liquid crystal display is being applied for a Rear-Seat Entertainment (RSE) system for enjoying DVD movies or games in the back seat of a vehicle.

Since the display for a vehicle requires visibility even in sunlight, high brightness is required compared to displays for other purposes, and reliability under vehicle temperature conditions and vibration conditions is required.

A liquid crystal display device includes a liquid crystal display panel and a backlight unit. The backlight unit has a structure in which a light source is disposed to face a side surface of the light guide plate and a plurality of optical sheets are disposed between the liquid crystal display panel and the light guide plate. The liquid crystal display panel and the backlight unit are assembled together with case members that fix them to be implemented as a liquid crystal module (LCM). The case member may include a guide panel, a cover bottom, a case top, and the like.

The position of the case members may be changed due to external factors such as external shock and vibration. The case members may be fastened to each other using a hook structure, but when hooks and hook holes into which the hooks are inserted are formed, the movement of the case members may not be constrained by the distance and tolerance between the fastening parts, and their positions may be moved. That is, the case members may not be fixed in a mutually molded state due to the external environment and may be spaced apart due to the above-described separation distance and tolerance. Accordingly, a problem in that the case members are not fixed in place and are separated may occur, and interference between the case members may occur, resulting in damage and noise.

An object of the present invention is to provide a liquid crystal display device capable of preventing movement of a case member that may occur due to external factors such as external shock and vibration.

A liquid crystal display device according to the present invention includes a liquid crystal display panel, a backlight unit disposed on the rear surface of the liquid crystal display panel, and a case member accommodating the liquid crystal display panel and the backlight unit therein. The case member includes a guide panel and a case top. The guide panel includes a panel support and an extension. The panel support part is provided between the liquid crystal display panel and the backlight unit to support an edge of the liquid crystal display panel from a lower portion. The extension part extends from the panel support part and wraps around the side surface of the backlight unit. The case top includes a horizontal portion and a vertical portion. The horizontal part surrounds the front edge of the liquid crystal display panel. The vertical portion extends from the horizontal portion and surrounds the extension of the guide panel from the outside. At least one of the extension part and the vertical part includes a forming part protruding between the extension part and the vertical part.

According to the present invention, a gap between the case top and the guide panel may be reduced by including a forming part provided on at least one of the case top and the guide panel. Accordingly, the present invention has the advantage of minimizing damage and noise caused by mutual interference between the case top and the guide panel.

1 is an exploded perspective view of a liquid crystal display device according to the present invention.
FIG. 2 is a cross-sectional view of FIG. 1 taken along line I-I'.
3 and 4 are those of FIG. 1 taken along line II-II'.
5 is a view for explaining the positional relationship between the hook structure and the forming part.
6 to 8 are views for explaining examples of the shape of the forming unit.

The manufacturing method of the liquid crystal display device includes substrate cleaning of the liquid crystal display panel, substrate patterning process, alignment film formation/rubbing process, substrate bonding and liquid crystal dropping process, driving circuit mounting process, backlight unit assembly process, liquid crystal module assembly process, etc. can do.

In the substrate cleaning process, foreign substances contaminated on the surfaces of the upper and lower substrates of the liquid crystal display panel are removed with a cleaning solution. The substrate patterning process includes a process of forming and patterning various thin film materials such as signal lines including data lines and gate lines, thin film transistors (TFTs), and pixel electrodes on the lower substrate, and black matrix and color on the upper substrate. It includes a process of forming and patterning various thin film materials such as a filter and a common electrode. In the alignment film formation/rubbing process, an alignment film is applied on substrates, and the alignment film is rubbed with a rubbing cloth or subjected to photo-alignment treatment. Through these series of processes, the data lines to which the video data voltage is supplied to the lower substrate of the liquid crystal display panel, the gate lines to cross the data lines and to sequentially supply the scan signal, that is, the gate pulse, the data lines and the gate A pixel and TFT array including TFTs formed at the intersection of the lines, pixel electrodes of a liquid crystal cell connected to the TFTs, and a storage capacitor are formed. A shift register of a gate driving circuit generating a scan signal may be formed simultaneously with a pixel and a TFT array in a substrate patterning process. A black matrix, a color filter, and a common electrode are formed on the upper substrate of the liquid crystal display panel. The common electrode is formed on the upper substrate in vertical electric field driving methods such as TN (Twisted Nematic) mode and VA (Vertical Alignment) mode, and horizontal electric field driving such as IPS (In Plane Switching) mode and FFS (Fringe Field Switching) mode. In this method, it is formed on the lower substrate together with the pixel electrode. A polarizing plate and a polarizing plate protective film are attached to each of the upper substrate and the lower substrate.

In the liquid crystal dropping and bonding process, sealant is drawn on one of the upper and lower substrates of the liquid crystal display panel and liquid crystal is dropped on the other substrate. When an ultraviolet light source is irradiated to the ultraviolet curable sealant through the upper or lower substrate of the liquid crystal display panel, the sealant is cured, and the upper and lower substrates are bonded with the liquid crystal layer interposed therebetween.

In the driving circuit mounting process, an integrated circuit (IC) of a data driving circuit is mounted on a lower substrate of a liquid crystal display panel using a COG (Chip On Glass) process or a COF (Chip On Film) process. As described above, the gate driving circuit may be directly formed on the lower substrate of the liquid crystal display panel, or may be attached on the lower substrate through a COF process in a driving circuit mounting process. Subsequently, in the driving circuit mounting process, an integrated circuit (IC) and a printed circuit board (PCB) are connected with a flexible printed circuit board (FPC) or a flexible flat cable (FFC).

In the assembling process of the backlight unit, wires are connected to the light source and connected to the light source driving circuit. In the assembly process of the liquid crystal module, a liquid crystal display panel equipped with a driving circuit and a backlight unit are assembled into a liquid crystal module using a guide panel, a cover bottom, and the like.

The manufacturing method of the liquid crystal display device may further include an inspection process and a repair process. The inspection process includes inspection of integrated circuits, signal wiring such as data lines and gate lines formed on the lower substrate, electrical inspection to detect defects in TFTs and pixel electrodes, electrical inspection performed after substrate bonding and liquid crystal dropping processes, and in a clean room. It includes a lighting inspection for detecting assembly defects of optical sheets performed in , and a lighting inspection for detecting defects in the liquid crystal module by turning on the backlight unit of the liquid crystal module. The repair process repairs signal wiring defects and TFT defects determined to be repairable by the inspection process.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings. Like reference numbers throughout the specification indicate substantially the same elements. In the following description, if it is determined that a detailed description of a known function or configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, the detailed description will be omitted. In describing various embodiments, the same components are representatively described at the beginning and may be omitted thereafter.

Terms including ordinal numbers, such as first and second, may be used to describe various components, but the components are not limited by the terms. These terms are only used for the purpose of distinguishing one component from another.

1 is an exploded perspective view of a liquid crystal display device according to the present invention. FIG. 2 is a cross-sectional view of FIG. 1 taken along line I-I'. 3 and 4 are those of FIG. 1 taken along line II-II'.

Referring to FIGS. 1 and 2 , the liquid crystal display device of the present invention includes a liquid crystal display panel (PNL) and a backlight unit disposed under the liquid crystal display panel (PNL). As described above, the liquid crystal display panel PNL includes an upper substrate USUB, a lower substrate LSUB, and a liquid crystal layer interposed between the upper substrate USUB and the lower substrate LSUB. The liquid crystal layer may be implemented in at least one mode among various liquid crystal modes.

Polarizing films UP and LP may be provided on the front and/or rear surface of the liquid crystal display panel PNL. The polarizing films UP and LP are provided on at least one of the front and rear surfaces of the liquid crystal display panel PNL to pass only components of light emitted from the backlight unit in a specific direction.

The backlight unit is provided under the liquid crystal display panel PNL, and irradiates light to the rear surface of the liquid crystal display panel PNL. The backlight unit includes a light source LS, a light guide plate LGP, and at least one optical sheet OPS. The light supplied from the light source LS to the light incident surface of the light guide plate LGP is converted into a form of the surface light source LS and emitted to the front surface of the light guide plate LGP, and the optical sheet positioned on the light guide plate LGP. While passing through (OPS), it is uniformly irradiated to the rear surface of the liquid crystal display panel (PNL).

The light source (LS) is one or more light sources (LS) of lamps such as a light emitting diode (LED), a cold cathode fluorescent lamp (CCFL), and an external electrode fluorescent lamp (EEFL). can include The light source LS radiates light to a side surface of the light guide plate LGP facing at least one side surface (or light incident surface) of the light guide plate LGP. The light guide plate (LGP) is a plate material molded from transparent plastic, for example, polymethacrylate (PMMA), and converts light in the form of a point light source (LS) or line light source (LS) into light in the form of a surface light source (LS). plays a role in converting

The optical sheet OPS includes one or more prism sheets and one or more diffuser sheets to diffuse light incident from the light guide plate LGP and to substantially affect the light incident surface of the liquid crystal display panel PNL. refracts the path of light at a perpendicular angle. The optical sheet OPS may further include functional sheets such as a multilayer optical film (DBEF-D (MOF)) and a protection film.

A reflection sheet REF may be disposed under the light guide plate LGP to increase the efficiency of the light incident on the liquid crystal display panel PNL by reflecting the light incident from the light guide plate LGP. The reflective sheet REF may be adhered to the cover bottom CB.

The liquid crystal display panel (PNL) and backlight unit are assembled together with the cover bottom (CB), guide panel (GP), and case top (CT) to form a liquid crystal module (LCM). can be implemented

A cross section of the cover bottom CB may be formed in an “L” shape having at least one curved portion. The cover bottom CB may be disposed to cover the side and rear surfaces of the backlight unit. A backlight unit including a light source LS, a light guide plate LGP, an optical sheet OPS, and the like is accommodated in the inner space provided by the cover bottom CB.

The cover bottom CB may include a material having high thermal conductivity and high stiffness so as to smoothly dissipate heat from the driving circuit and the light source LS to the outside. For example, the cover bottom (CB) is made of aluminum, aluminum nitride (AlN), electro-galvanized steel (EGI), stainless (SUS), galvalume (SGLC), aluminum-plated steel (aka ALCOSTA), tin-plated steel (SPTE) It may be made of a metal plate such as In addition, such a metal plate may be coated with a high-conductivity material to promote heat transfer.

A cover shield CS may be disposed at one edge of the cover bottom CB. The cover shield CS may be provided in an area corresponding to an area where a driving circuit, a PCB, and the like are disposed. The cover bottom CB and the cover shield CS may include a material having high thermal conductivity and high stiffness so as to smoothly dissipate heat from the driving circuit and the PCB to the outside. For example, the cover bottom (CB) is made of aluminum, aluminum nitride (AlN), electro-galvanized steel (EGI), stainless (SUS), galvalume (SGLC), aluminum-plated steel (aka ALCOSTA), tin-plated steel (SPTE) It may be made of a metal plate such as In addition, such a metal plate may be coated with a high-conductivity material to promote heat transfer.

A cross section of the guide panel GP may be formed in an “L” shape having at least one bent portion. The guide panel GP includes a panel support part SP and an extension part LP. The panel support part SP is provided between the liquid crystal display panel PNL and the backlight unit, and supports the edge of the liquid crystal display panel PNL from the lower side. The panel support part SP is provided between the liquid crystal display panel PNL and the optical sheet OPS to maintain a constant distance between the liquid crystal display panel PNL and the optical sheet OPS.

The extension part LP extends from the panel support part SP and is disposed to surround the cover bottom CB from the outside. The extension part LP extends from one end of the panel support part SP in the rear direction. Also, the extension part LP may be disposed to extend from one end of the panel support part SP toward the front side and surround the side surface of the liquid crystal display panel PNL from the outside.

The guide panel GP may have a rectangular frame shape through which a center is penetrated. The guide panel GP may be made of a plastic-based material that can be molded into a mold, such as polycarbonate.

The liquid crystal display panel PNL and the guide panel GP may be mutually fixed by the adhesive layer LSA. The adhesive layer LSA is interposed between the edge of the liquid crystal display panel PNL and the panel support part SP of the guide panel GP. The adhesive layer LSA may perform a function of restraining and restricting mutual movement of the liquid crystal display panel PNL and the guide panel GP and a function of buffering an applied external force. In addition, the adhesive layer LSA may function as a light blocking member by including a light blocking material to prevent light from leaking to the edge of the liquid crystal display panel PNL.

The case top CT is disposed to surround the side surfaces of the guide panel GP and the cover bottom CB. The case top CT may be formed in an “L” shape having at least one bent portion in its cross section. The case top CT includes a horizontal portion HP and a vertical portion VP. The horizontal portion HP covers the front edge of the liquid crystal display panel PNL. The vertical portion VP extends from the horizontal portion HP and is disposed outside the guide panel GP to surround the extension portion LP of the guide panel GP. The vertical portion VP extends from one end of the horizontal portion HP in the rear direction. The case top CT may be made of a metal plate such as electro-galvanized steel (EGI), stainless (SUS), galvalume (SGLC), aluminum-coated steel (aka ALCOSTA), or tin-plated steel (SPTE).

The position of the case members may be changed due to external factors such as external shock and vibration. To prevent this, the case top CT may be fixed to the guide panel GP by a hook fastening method. For example, the extension part LP of the guide panel GP includes a hook HK protruding toward the vertical part VP of the case top CT, and the vertical part VP of the case top CT A hook hole HH into which the hook HK can be inserted may be included.

However, even if the case top (CT) and the guide panel (GP) are mutually fastened using the hook structure, the gap between the hooks (HK) and the fastening parts that inevitably occur when the hook hole (HH) into which the hooks (HK) are inserted is formed. Due to the spacing and tolerance, mutual movement is not constrained and the position can be fluctuated.

For example, between the vertical portion VP of the case top CT and the extension portion LP of the guide panel GP (Gxy) and/or between the hook HK and the hook hole HH (Gz), there is a tolerance And a separation space inevitably occurs according to the skill level of the process equipment. Therefore, the case top CT and the guide panel GP may be spaced apart from each other without maintaining a molded state due to the external environment due to the above-described separation distance and tolerance.

In this case, the case top CT and the guide panel GP may be separated from each other without being fixed in place, and mutual interference may occur, resulting in damage and noise. In addition, since the case top CT and the guide panel GP are not firmly coupled, mutual interference may occur between the liquid crystal display panel and the backlight unit accommodated inside the case top CT and the guide panel GP.

Referring further to FIG. 3 , the present invention includes forming parts CF and GF provided on at least one of the guide panel GP and the case top CT to solve the above problems. The forming parts CF and GF may include at least one of the first forming part GF and the second forming part CF.

The first forming part GF is provided on the extension part LP of the guide panel GP and protrudes toward the vertical part VP of the case top CT. As the first forming part GF is disposed adjacent to the vertical part VP of the case top CT in the X-axis direction, the extension part LP of the guide panel GP and the vertical part of the case top CT The separation interval (G1) between (VP) is reduced. Accordingly, the present invention has an advantage of preventing damage and noise caused by mutual interference by reducing the gap between the guide panel GP and the case top CT (FIG. 3(a)).

The second forming part CF is provided on the vertical part VP of the case top CT and protrudes toward the extension part LP of the guide panel GP. As the second forming part CF is disposed adjacent to the extension part LP of the guide panel GP in the X-axis direction, the extension part LP of the guide panel GP and the vertical part of the case top CT The separation interval (G1) between (VP) is reduced. Accordingly, the present invention has an advantage of preventing damage and noise caused by mutual interference by reducing the gap between the guide panel GP and the case top CT (FIG. 3(b)).

Referring further to FIG. 4 , the liquid crystal display according to an exemplary embodiment may include both a first forming part GF and a second forming part CF. The first forming part GF and the second forming part CF are alternately arranged. The first forming part GF and the second forming part CF protruding in opposite directions may be alternately disposed and engaged with each other.

The first forming part GF and the second forming part CF are disposed to cross each other, but are disposed adjacent to each other in the Z-axis direction. It is preferable that the first forming part GF and the second forming part CF have a minimum distance G2 in the Z-axis direction.

As the first forming part GF and the second forming part CF are disposed adjacent to each other in the Z-axis direction, the movement of the case top CT and the guide panel GP in the second direction may be limited and restrained. there is. That is, one embodiment of the present invention minimizes the gap that may occur as Gz is inevitably spaced between the hook HK and the hook hole HH due to the tolerance and actual value of the process equipment when forming the hook structure. can An embodiment of the present invention has an advantage of minimizing damage and noise caused by mutual interference by reducing the gap between the guide panel GP and the case top CT.

5 is a view for explaining the positional relationship between the hook structure and the forming part.

Referring to FIG. 5 , the hook structure and the forming parts CF and GF may be provided on at least one of four edges of the case top CT (and guide panel GP). Although not shown, one edge of the case top CT may be fixed through the guide panel GP and an adhesive member.

The case top CT (and the guide panel GP) may include a first section HP having a hook structure and a second section FP having the forming parts CF and GF. The first section HP and the second section FP are at least one side edge of the case top CT (and the guide panel GP) to firmly fasten the case top CT and the guide panel GP. It may be preferable to alternate with each other in However, the location and number of the first section HP and the second section FP are not limited to those shown in the drawing.

6 to 8 are views for explaining examples of the shape of the forming unit.

Referring to FIG. 6 , the first forming part GF and the second forming part CF may be provided in a dot shape. In the present invention, by forming the forming parts CF and GF in a point shape, it is possible to easily process the forming parts CF and GF through a mold process. That is, when the forming parts CF and GF are formed in a point-like shape, the depth of the forming parts CF and GF can be easily adjusted during molding, and the forming parts CF and CF having various planar shapes such as circular and square shapes GF) may be easy to implement. In addition, since the area occupied by the forming parts CF and GF is small, there is an advantage in that space restrictions for forming the forming parts CF and GF are small.

Referring to FIG. 7 , the first forming part GF and the second forming part CF may be provided in a linear shape extending in one direction (X-axis direction or Y-axis direction). When the forming parts CF and GF are formed linearly, since the area occupied by the forming parts CF and GF is large, it may be easy to restrict movement between the case top CT and the guide panel GP. For example, when the dot-shaped first forming part GF and the second forming part CF are provided, since the area occupied by each forming part CF and GF is small, it is difficult to align the movement in the Z-axis direction. Although it may be difficult to restrain, in the case of having a linear first forming part (GF) and a second forming part (CF), each forming part (CF, GF) can be formed to have a sufficient area to facilitate alignment. there is.

Referring to FIG. 8 , at least one of the first forming part GF and the second forming part CF may be provided in a dotted shape, and the other may be provided in a linear shape. In this case, there is an advantage of being able to accommodate both the advantages of the point-shaped forming parts CF and GF and the linear-shaped forming parts CF and GF.

Through the above description, those skilled in the art will be able to make various changes and modifications without departing from the spirit of the present invention. Therefore, the technical scope of the present invention is not limited to the contents described in the detailed description of the specification, but should be defined by the claims.

PNL: Liquid crystal display panel GP: Guide panel
SP: Panel Support LP: Extension
CT: Case top HP: Horizontal part
VP: vertical part GF: first forming part
CF: second forming part

Claims (7)

A liquid crystal display device comprising a liquid crystal display panel, a backlight unit disposed on a rear surface of the liquid crystal display panel, and a case member accommodating the liquid crystal display panel and the backlight unit therein,
The case member,
a guide panel having a panel support portion disposed between the liquid crystal display panel and the backlight unit to support an edge of the liquid crystal display panel from a lower portion, and an extension portion extending from the panel support portion and surrounding a side surface of the backlight unit; and
a case top having a horizontal portion surrounding a front edge of the liquid crystal display panel and a vertical portion extending from the horizontal portion and surrounding the extension portion of the guide panel from the outside;
At least one of the extension part and the vertical part,
A forming part protruding between the extension part and the vertical part,
The forming part protrudes in the X-axis direction from the extension part or the vertical part,
The forming part is disposed adjacent to the vertical part or the extension part in the X-axis direction,
The forming part is spaced apart from the vertical part or the extension part in the X-axis direction,
The extension part and the vertical part,
It is fastened with a hook structure,
The case member,
a first section provided with the hook structure; and
Including a second section provided with the forming portion,
The liquid crystal display device wherein the first section and the second section are alternately arranged. According to claim 1,
The forming part,
A liquid crystal display device having a linear shape extending in one direction. According to claim 1,
The forming part,
A liquid crystal display having a dotted shape. According to claim 1,
The forming part,
a first forming portion protruding from the extension portion toward the vertical portion; and
And a second forming portion protruding from the vertical portion toward the extension portion,
The first forming part and the second forming part,
Liquid crystal display devices provided so as to alternate with each other. According to claim 4,
Any one of the first forming part and the second forming part,
It has a linear shape extending in one direction,
The other one of the first forming part and the second forming part,
A liquid crystal display having a dotted shape. delete delete

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