KR100965185B1 - Liquid crystal display using dummy film - Google Patents

Abstract

The present invention relates to a liquid crystal display device using a dummy film wired the drive line of the gate IC using a dummy film, the TFT substrate 110 and the color filter 120 is bonded to form a liquid crystal panel 100, A gate IC 112 is installed at at least one outer side of the TFT substrate 110, and a driving line 155 including a power line and a signal line of the gate IC 112 is an outer portion of the liquid crystal panel 100. In the liquid crystal display device mounted along a line, a plurality of dummy films 150 are bonded to the glass region 160 outside the TFT substrate 110 adjacent to the gate IC 112 and bonded to the gate IC. The drive line 155 of 112 is mounted via the dummy film 150, and the wiring resistance of the drive line 155 is reduced to ensure stable operation of the IC, and the liquid crystal panel 100 is surrounded by To reduce the image non-display area 105 and simplify components It has the effect of implementing the right bezel.

LCD, liquid crystal panel, dummy film, gate IC, COF, drive line, dummy pad

Description

Liquid crystal display using dummy film

The present invention relates to a liquid crystal display device using a dummy film, and more particularly, to reduce the wiring resistance in the driving line of the gate IC to ensure stable operation of the IC and to implement a narrow bezel. It relates to a display device.

In general, a liquid crystal display (LCD) is formed by bonding a TFT (Thin Film Transistor) substrate and a color filter to form a liquid crystal panel, and a back light unit (BLU) is installed on the rear side of the liquid crystal panel. do. In such an LCD, when a predetermined voltage is applied to the TFT formed on the TFT substrate, the arrangement of the liquid crystals enclosed in the liquid crystal panel is changed, and the optical characteristics of the light passing through the polarizing plate and the liquid crystal are changed to color through the color filter. It is a display means for outputting the image.

1 shows a laminated structure of a typical LCD. The LCD usually has a structure in which a BLU 10, a TFT substrate 20, and a color filter 30 are stacked in a chassis not shown. The BLU 10 is a light emitting means for giving visibility to the LCD. The TFT substrate 20 is provided with a TFT, a charge accumulation capacitor, a gate line wiring, a source line wiring, and the like, and is bonded to the color filter 30 to form a liquid crystal panel 40. The color filter 30 imparts a color to the amount of light that changes according to the arrangement change of the liquid crystal, and a photoresist of RGB is deposited on the glass substrate, and a polarizing film is attached onto the color filter 30. A drive IC for driving the panel is mounted at the edge portion of the TFT substrate 20. In most cases, the source IC 23 is mounted on the lower edge portion of the TFT substrate 20, and the gate IC 27 is mounted on the side edge portion of the TFT substrate 20.

2 shows an example in which a conventional TFT substrate 20 and a color filter 30 are bonded to form a liquid crystal panel 40. Referring to this, the source IC 23 and the gate IC 27 are mounted on a chip on the film 33 and 37, respectively, and the COFs 33 and 37 are respectively lower side of the liquid crystal panel 40. It is bonded to the glass area of an edge part and a right edge part. Although not shown, the source IC 23 and the gate IC 27 may be mounted in the form of a chip on the glass (COG).

Although not shown, a seal line for bonding the TFT substrate 20 and the color filter 30 is applied to the outer line of the liquid crystal panel 40, and the Vcom voltage is applied to the TFT substrate 20 or the color filter 30. The Vcom line and the like for mounting are mounted, and the seal line and the Vcom line are concealed by a black matrix (BM) printed on the bottom surface of the color filter 30. The area where the BM is printed forms an image non-display area 35 as the area hatched in FIG.

Drive lines 39 such as a power supply line, a signal line, and a clock are connected to the gate ICs 27 of the right edge portion on the liquid crystal panel 40 by the path as shown. Referring to FIG. 2, the driving line 39 is drawn out of the T_con block 70 for transmitting the driving signal to the gate ICs 27, and the driving line 39 includes the source IC 23 mounted thereon. The COF 33 is transferred to the gate IC 27 via the glass region of the lower edge portion of the TFT substrate 20, the glass region of the right edge portion of the TFT substrate 20, or the image non-display region 35.

However, the driving line 39 is connected to a substantial portion of the glass region or the image non-display region 35, thereby causing a problem in that the wiring resistance increases. In general, in forming the driving line 39 by depositing aluminum, chromium, molle, or the like on a glass substrate such as the TFT substrate 20, the thickness and width of the driving line 39 may be limited due to design and process limitations. none. Therefore, the wiring resistance of the driving line 39 increases, which causes a loss of a signal transmitted to the gate IC 27.

FIG. 3 is a graph showing operation characteristics of TFTs disposed on the TFT substrate 20. When the gate off voltage VGL is determined in a region where the log current Log Id of the TFTs is the smallest, a point in which Log Id is substantially saturated is shown. In VGH, the gate on voltage is determined. At this time, an increase in wiring resistance in the driving line 39 of the gate IC 27 causes the VGL to gradually shift to the right. This VGL shift causes some TFTs to not turn off normally even when a gate off signal is applied to the gate IC 27. In addition, if the TFTs are not turned off normally, some data may interfere with other areas, causing cross talk, which causes malfunction of adjacent TFTs. That is, an increase in wiring resistance caused by the driving line 39 of the gate IC 27 causes a loss of a signal. As a result, TFTs of the TFT substrate 20 operate abnormally, causing cross talk and image quality. The problem of deterioration arises.

On the other hand, another problem in that the driving line 39 of the gate IC 27 is wired to the image non-display area 35 is inevitable because the plurality of driving lines 39 are each wired to have a predetermined width. This is because the display area 35 is widened. As such, when the image display area 35 is widened, the bezel width of the front of the LCD is increased.

In the case of general LCDs, the increase in the bezel width does not affect the competitiveness of the product. However, when a plurality of large-screen LCDs (approximately 40 inches or more) are combined to form a so-called "tiled" type multi-screen, the bezel outside the LCD is It decreases the continuity of the screen and acts as a factor that hinders the readability of characters.

The present invention has been proposed to solve the above problems, bonding a dummy film to the outer portion of the liquid crystal panel and mounting the drive line of the gate IC on the dummy film, the glass region or the image display area of the liquid crystal panel It provides a liquid crystal display device using a dummy film that minimizes the drive line wiring of the gate IC through the light source and ultimately reduces the wiring resistance of the drive line to ensure stable operation of the IC and to implement a narrow bezel. The purpose is.

In addition, another object of the present invention is to provide a liquid crystal display using a dummy film, which simplifies the bonding process of the dummy film, shortens the LCD manufacturing process and reduces the incidence of defective products during the process.

In addition, another object of the present invention is to prevent a short from occurring at a connection portion between pads when bonding a dummy film to a glass region.

In addition, the present invention has another object to minimize the wiring through the glass region by mounting the drive line to a single dummy film of a long side when the gap between the COF mounted with the gate IC is required to have two or more dummy films.

In the liquid crystal display device using the dummy film of the present invention for achieving the above object, the TFT substrate 110 and the color filter 120 is bonded to form a liquid crystal panel 100, the TFT substrate 110 A liquid crystal display in which at least one outer side of the gate IC 112 is installed and a driving line 155 including a power line and a signal line of the gate IC 112 is mounted along the outer line of the liquid crystal panel 100. In the device, a plurality of dummy films 150 are bonded to the glass region 160 outside the TFT substrate 110 adjacent to the gate IC 112, and the driving line 155 of the gate IC 112 is bonded. ) Is mounted via the dummy film 150.

According to a preferred embodiment of the present invention, the gate IC 112 is mounted on the COF 122 bonded to the glass region 160 outside the TFT substrate 110, the dummy film 150 is The film is installed adjacent to the COF 122 but is selected as a film having the same coefficient of expansion as the COF 122. More preferably, the dummy film 150 is selected from the same standard and the same material as the COF 122, and is disposed to have the same pad pitch.

According to a more preferred embodiment, the dummy film 150 has a plurality of connection pads 157 connected to the drive line 155, and are disposed adjacent to the connection pads 157 and are not connected to the drive line 155. A plurality of dummy pads 159 are provided; In the glass region 160 to which the dummy film 150 is bonded, a plurality of connection pads 167 connected to the respective connection pads 157 and a plurality of dummy disposed adjacent to the connection pads 167 are provided. The pad 159 is provided.

In addition, the dummy film 150 may include a plurality of bonding portions 158 bonded to the glass regions 160, and each bonding portion 158 may have the same bonding region as the COF 122.

According to the liquid crystal display device using the dummy film of the present invention, by bonding a similar dummy film between COF or COFs in which the gate IC is mounted, and mounting a drive line of the gate IC on the dummy film, the glass outside the liquid crystal panel Minimize the wiring of the gate IC drive line to the area or the non-display area, and ultimately reduce the wiring resistance of the drive line to ensure stable operation of the IC, prevent cross talk, and implement a narrow bezel. When configuring a multi-screen of a tiled type in which a plurality of LCDs are combined, there is an effect of improving the continuity of the screen at the border between LCDs.

Further, according to the present invention, the gate ICs are mounted on the COF and the dummy film is selected to have the same expansion coefficient as the gate IC mounting COF, so that the gate IC mounting COF and the dummy film can be bonded under the same conditions. In addition to simplifying the manufacturing process, there is no need to use external transmission media such as PCBs, which simplifies the components and can be aimed at the narrow bezel.

In addition, according to the present invention, the dummy film and the plurality of dummy pads to which the driving line is not connected are disposed in the glass region to which the dummy film is bonded, respectively, so that a short is generated between the connection pads even when the dummy film is bonded in an unaligned state. There is an effect to prevent the occurrence.

In addition, according to the present invention, a plurality of bonding portions in which the dummy film is bonded to the glass region may be provided, so that a single dummy film may be installed between the COFs having the gate IC mounted thereon to mount the driving line therebetween. The driving line passing through the glass area of the liquid crystal panel can be further minimized.

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

First, the present invention is to minimize the wiring of the driving line of the gate IC through the glass area or the image non-display area outside the liquid crystal panel, bonding a plurality of dummy film adjacent to the gate IC, the dummy film A liquid crystal display device having a drive line of a gate IC mounted thereon. Embodiments to be referred to in the following description will focus on the installation example of the dummy film in the liquid crystal panel, and other detailed descriptions of general technologies related to the liquid crystal display will be omitted.

4 is a plan view showing a configuration example of a liquid crystal panel according to the present invention. 4 illustrates a liquid crystal panel 100 in which a TFT substrate 110 and a color filter 120 are bonded to each other, and a glass region 160 for mounting a gate IC 112 is formed at a right edge of the TFT substrate 110. Is formed. In the illustrated example, the gate IC 112 is mounted on the COF 122 bonded to the glass region 160. However, the gate IC 112 may be mounted in the glass region 160 in the form of COG. In addition, the gate IC 112 may be provided at the left edge portion of the TFT substrate 110 or may be provided at both edge portions thereof. The source IC 116 is mounted on the COF 126 at the lower edge portion of the TFT substrate 110. As is well known, the gate IC 112 is a drive IC that applies a drive signal to a horizontal gate line formed on the TFT substrate 110, and the source IC 116 applies a drive signal to a source line in the longitudinal direction. Drive IC.

As shown, an image non-display area 105 is formed along the outer line of the liquid crystal panel 100 by the black matrix on the bottom surface of the color filter 120. In more detail, when fabrication of each of the TFT substrate 110 and the color filter 120 is completed, the foreign matter on the surface is removed through a cleaning process, a process of printing an alignment film, and the like, followed by the TFT substrate 110 and the color filter. A seal is applied along the outline of 120. In addition, a Vcom line for transferring the Vcom voltage to the TFT substrate 110 or the color filter 120 side is mounted along the outer line of the liquid crystal panel 100. On the lower surface of the color filter 120, a black matrix is printed to conceal such a seal line and a Vcom line, and a region hidden by the black matrix is an image non-display area 105. On the other hand, the black matrix may be partially removed in some cases.

At this time, in the LCD having the dummy film of the present invention, as shown, a plurality of dummy films 150 are bonded between the COFs 122 on which the gate IC 112 is mounted. As shown in FIG. 4, the drive line 155 of the gate IC 112 is mounted to pass through the dummy film 150. More specifically, the driving line 155 applied by the T_con block 140 generating the driving signal of the gate IC 112 is the dummy film 150 through the glass region 160 at the lower right end of the liquid crystal panel 100. The plurality of dummy films 150 and the gate IC 112 are transferred to the top gate IC 112 through the mounted COFs 122.

As such, since the driving line 155 of the gate IC 112 is mounted on the dummy film 150, the conductive line may not be limited to the material for wiring the driving line 155, such as copper (Cu). This good material can be selected. In addition, the mounting method of the driving line 155, as well as the restrictions on the thickness and width are also eliminated. Therefore, the drive line 155 can be designed with sufficient thickness and width, which means that the wiring resistance in the drive line 155 can be greatly reduced.

Further, as shown, the COF 122 and the dummy film 150 in which the gate IC 112 is mounted are provided to have a substantial proportion of the area in the glass region 160 on the right side of the liquid crystal panel 100. Therefore, the driving lines 155 of the gate IC 112 are mostly wired through the COF 122 and the dummy film 150, and the glass region 160 or the image non-display region 105 of the liquid crystal panel 100 is connected. Wiring through is extremely small. In addition, the use of a separate external transfer medium for wiring the drive line 155 may be excluded. Therefore, the image non-display area 105 outside the liquid crystal panel 100 and the glass area 160 for installing the IC can be designed to be slim, and the installation of additional components outside the liquid crystal panel 100 can be reduced. Can, as a result, enable the inner bezel.

In the present invention, the dummy film 150 is a blank film in which the gate IC is not mounted, and is preferably installed to have the same design rule as the COF 122 in which the gate IC 112 is mounted. For example, the dummy film 150 is selected as a film having the same coefficient of expansion as the COF 122 for mounting the gate IC 112. In general, the process of bonding the film to the glass region 160 of the TFT substrate 112 is performed in a state in which the connection pads 167 of the glass region 160 and the connection pads 157 on the film are adhered with an adhesive including a conductive ball. It is done by applying constant heat and pressure. At this time, when the dummy film 150 and the COF 122 for mounting the gate IC 112 have the same expansion coefficient, the COF 122 and the dummy film do not require separate process conditions for bonding the dummy film 150. Since 150 can be bonded under the same process conditions, the manufacturing process of the liquid crystal display device can be shortened by that amount. More preferably, the dummy film 150 is selected from the same standard and the same material as the COF 122 for mounting the gate IC 112 and disposed at the same pad pitch. In this case, the bonding process of the film may be further simplified.

On the other hand, when bonding a film such as COF 122 to the glass region 160, in the process of pressing the film, the connection pads 167 of the glass region 160 and the connection pads 157 on the film due to a process defect. ) Is often displaced and a short occurs. When the plurality of dummy films 150 are additionally bonded as in the present invention, this process defect may be increased. Accordingly, the present invention proposes a method capable of preventing a short between the connection pads 157 and 167 even in such a process failure.

Figure 5 is a schematic view showing an example provided with a dummy pad on the dummy film in the present invention. Referring to this, the dummy film 150 includes a plurality of connection pads 157 connected to the driving line 155, and a plurality of dummy pads (not connected to the driving line 155 between the connection pads 157). 159 are arranged together. Similarly, the connection pads 167 and the dummy pads 169 connected to the driving line 155 are also disposed in the glass region 160. FIG. 5 illustrates a fine miss during the bonding process between the dummy film 150 and the glass region 160 in a state in which the plurality of dummy pads 159 and 169 are disposed in the dummy film 150 and the glass region 160, respectively. Shows when -align occurs. As shown, even when a slight miss-align occurs, the dummy pads 159 and 169 to which the driving line 155 is not connected are shorted with the connection pads 157 and 167 and between the connection pads 157 and 167. Short can be prevented. Therefore, short phenomenon of power and signal can be prevented even when a slight miss-align occurs due to a process defect of the dummy film 150. Of course, excessive miss-align will have to be handled.

On the other hand, when the gap between the COF 122 in which the gate IC 112 is mounted is wide, two or more dummy films 150 may need to be installed between the COF 122. As such, when the plurality of dummy films 150 are installed between the COFs 122, wiring through the glass region 160 may be increased between the dummy films 150.

The present invention proposes an embodiment as shown in FIG. 6 in order to prevent an increase in wiring through the glass region 160 as described above. 6 is a partial plan view showing another installation example of the dummy film according to the present invention. Referring to this, the dummy film 150 may include two or more bonding portions 158 bonded to the glass region 160. Preferably, each junction 158 has the same junction area as COF 122. Therefore, while maintaining the advantage of bonding the COF 122 and the dummy film 150 together in a single bonding process, even if the distance between the COF (122) is a long gate IC (a single dummy film 150) The drive line 155 of 112 may be wired. This eliminates any wiring through the glass region 160, thereby further reducing the wiring resistance, and has an advantage of preventing a phenomenon such as distortion of a signal or deterioration of image quality.

The technical idea of the present invention described above is not limited to the above-described embodiments and the accompanying drawings, and the present invention is capable of various substitutions, modifications, and changes without departing from the technical spirit of the present invention. It will be apparent to those with the usual Equation in the art.

1 is an exploded perspective view showing a laminated structure of a general LCD

2 is a plan view showing a configuration example of a conventional liquid crystal panel

3 is a graph showing the operation characteristics of a typical TFT

4 is a plan view showing a configuration example of a liquid crystal panel according to the present invention;

5 is a schematic view showing an example provided with a dummy pad on a dummy film in the present invention;

Figure 6 is a partial plan view showing another installation example of the dummy film according to the present invention

<Explanation of symbols for the main parts of the drawings>

100: liquid crystal panel 105: image non-display area

110 TFT substrate 112 gate IC

116 Source IC 120 Color Filter

122: COF 126: COF

140: T_con block 150: dummy film

155: drive line 157: connection pad

158: junction 159: dummy pad

160: glass area 167: connection pad

169: Dummy Pad

Claims (5)

The TFT substrate 110 and the color filter 120 are bonded to each other to form the liquid crystal panel 100. A gate IC 112 is provided at at least one outer side of the TFT substrate 110, and the gate IC 112 is disposed. In the liquid crystal display device in which a driving line 155 including a power line and a signal line of the is mounted along an outer line of the liquid crystal panel 100, A plurality of dummy films 150 are bonded to the glass region 160 outside the TFT substrate 110 adjacent to the gate IC 112, and the driving line 155 of the gate IC 112 is connected to the dummy area. Mounted via film 150; The gate IC 112 is mounted on a COF 122 bonded to the glass region 160 outside the TFT substrate 110, and the dummy film 150 is disposed adjacent to the COF 122. Liquid crystal display using a dummy film, characterized in that the film is selected as a film having the same coefficient of expansion as the COF (122). delete The method of claim 1, The dummy film 150 is selected from the same standard and the same material as the COF 122, the liquid crystal display device using a dummy film, characterized in that arranged to have the same pad pitch. The TFT substrate 110 and the color filter 120 are bonded to each other to form the liquid crystal panel 100. A gate IC 112 is provided at at least one outer side of the TFT substrate 110, and the gate IC 112 is disposed. In the liquid crystal display device in which a driving line 155 including a power line and a signal line of the is mounted along an outer line of the liquid crystal panel 100, A plurality of dummy films 150 are bonded to the glass region 160 outside the TFT substrate 110 adjacent to the gate IC 112, and the driving line 155 of the gate IC 112 is connected to the dummy area. Mounted via film 150; The dummy film 150 includes a plurality of connection pads 157 connected to the driving line 155, and a plurality of dummy pads 159 disposed adjacent to the connection pad 157 and not connected to the driving line 155. Is provided; In the glass region 160 to which the dummy film 150 is bonded, a plurality of connection pads 167 connected to the respective connection pads 157 and a plurality of dummy disposed adjacent to the connection pads 167 are provided. Liquid crystal display using a dummy film, characterized in that the pad 159 is provided. The TFT substrate 110 and the color filter 120 are bonded to each other to form the liquid crystal panel 100. A gate IC 112 is provided at at least one outer side of the TFT substrate 110, and the gate IC 112 is disposed. In the liquid crystal display device in which a driving line 155 including a power line and a signal line of the is mounted along an outer line of the liquid crystal panel 100, In the glass region 160 outside the TFT substrate 110, a COF 122 in which the gate IC 112 is mounted and a plurality of dummy films 150 are bonded to the COF 122. A drive line 155 of the IC 112 is mounted via the dummy film 150; The dummy film 150 includes a plurality of bonding portions 158 bonded to the glass region 160, and each bonding portion 158 has the same bonding region as the COF 122. Liquid crystal display device.

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