JPH04313731A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To obtain the liquid crystal display device which is small in size and has good productivity. CONSTITUTION:The display device is constituted of a liquid crystal display panel 1 provided with plural picture element electrodes formed by using a transparent conductive film on glass plates 2, 3, plural connecting terminals 7 for supplying a driving voltage to these picture element electrodes, and a bus line 13 which consists of a connecting part 14 formed along this connecting terminal 14 and a lead part 15 bent from this connecting part 14 and formed, and in which plural pieces of connecting parts 14 and lead parts 15 thereof are formed in parallel, and a film carrier 9 loaded with a driving IC 8 having plural input leads and output leads connected to the connecting terminal 7 of the picture element electrode and the connecting part 14 of the bus line 13, and for supplying a driving voltage to the picture element electrode.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure of a connecting portion for connecting a circuit board on which liquid crystal driving electronic components are mounted and a liquid crystal display panel in a liquid crystal display device.

0002

[Prior Art] FIG. 4 shows, for example, Japanese Patent Application Laid-Open No. 62-238684
5 is a perspective view showing the configuration of a conventional liquid crystal display device published in the publication, and FIG. 5 is a cross-sectional view of the liquid crystal display device in FIG. 4. In the figure, 1 is a liquid crystal display panel, which includes two transparent glass plates 2 and 3 with a plurality of transparent electrode films formed on one side, and a sealant 4 that holds and adheres these glass plates 2 and 3 at a predetermined distance. and a liquid crystal 5 sealed between two glass plates 2 and 3.
and a polarizing plate 6 arranged on two glass plates 2 and 3. At the end of the glass plate 2, there are connection terminals 7 for pixel electrodes drawn out from each pixel electrode of the liquid crystal 5. is formed. 8 is a liquid crystal driving IC which is an electronic component that supplies a liquid crystal driving signal to a pixel electrode; 9 is a liquid crystal driving IC 8 which is constructed by forming a copper foil pattern on a polyimide film;
A film carrier, which is a circuit board on which an IC is mounted
One terminal 10 is connected to the output lead of IC 8 and projects from the film carrier 9, and the other terminal 11 is connected to the input lead of IC 8 and projects from the film carrier 9. 12 is a hard printed circuit board arranged around the liquid crystal display panel 1, and on this hard printed circuit board 12 there is a bus line 1 that supplies input signals to the IC 8.
3 and a connecting portion 14 for the bus line 13 are formed. Such a conventional liquid crystal display device connects a connection terminal 10 on a film carrier 9 to a connection terminal 7 of a pixel electrode formed on a glass plate 2 using an anisotropic conductive film or solder, and also connects a connection terminal 10 of a pixel electrode formed on a glass plate 2 using an anisotropic conductive film or solder. The connection terminal 1 on the film carrier 9 is connected to the connection part 14 of the bus line formed on the substrate 12.
1 is soldered together.

0003

[Problems to be Solved by the Invention] As described above, a conventional liquid crystal display device has a liquid crystal display panel 1, a film carrier 9,
, since it is constructed of a hard printed circuit board 12, there is a drawback that the external area of the device is larger than the area of the liquid crystal display. Furthermore, the plurality of film carriers 9 had to be connected to the liquid crystal display panel 1 and the hard printed circuit board 12 separately, resulting in poor productivity. Also,
If even one of the plurality of film carriers 9 is connected diagonally to the liquid crystal panel 1, the connection position between the film carrier 9 and the rigid printed circuit board 12 will shift, and there is a problem that connection between the two cannot be established. . Furthermore, in the conventional liquid crystal display device, the liquid crystal display panel 1 and the rigid printed circuit board 12 are bridged by the film carrier 9, so during the device assembly stage when these are not fixed to a cabinet or the like, Due to vibrations during transportation, etc., force due to the load of the liquid crystal display panel 1 is applied to the connection parts, and when the liquid crystal display panel 1 becomes larger, the connection terminals 7 and 10 of the pixel electrodes may There was a problem in that the connection part between the connection part 14 of the bus line 13 and the connection terminal 11, and the connection part between the lead terminal of the IC 8 and the wiring were disconnected. The present invention was made to solve these problems, and provides a liquid crystal display device that is compact and has high connection reliability while reducing material and production costs.

0004

[Means for Solving the Problems] A liquid crystal display device according to the present invention includes a plurality of connection terminals for supplying driving voltage to pixel electrodes, a connection portion formed along the connection terminals, and a portion bent from the connection portion. A liquid crystal display panel is provided with a bus line in which a plurality of connection parts and a plurality of lead parts are formed in parallel. The device includes an input lead and an output lead, and a circuit board on which electronic components for supplying a driving voltage to the pixel electrodes are mounted.

[0005]

[Function] According to the liquid crystal display device of the present invention, the connection portion of the bus line is formed along the plurality of connection terminals of the pixel electrode, and the lead portion bent from the connection portion is provided, so that the bus line can be connected to each other. without crossing
Since the liquid crystal display panel and film carrier can be connected all at once, productivity can be improved, and
Since a hard printed circuit board is not required, the device can be made smaller and connection reliability can be improved.

[0006]

[Embodiment] An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, a plurality of connection terminals 10 and 11 are arranged on a rectangular film carrier 9 in parallel with each other and protruding from the film carrier 9. Further, on the rectangular liquid crystal display panel 1, a plurality of connection terminals 7 drawn out from pixel electrodes are formed in parallel with each other. Furthermore, a bus line 13 is arranged along the outer periphery of the liquid crystal display panel 1, and this bus line 13 is provided near the connection terminal 7 in a right angle direction from the outer periphery toward the center, and then parallel to the outer periphery. The connecting portion 14 is formed along the connecting terminal 7 by bending it at a right angle toward the outer periphery. Thereafter, the connecting portion 14 is further bent and a lead portion 15 is provided along the outer periphery again, and a plurality of these connecting portions and lead portions are formed in parallel. Under such a configuration, the connecting portion 14 of the bus line 13 and the connecting terminal 11, and the connecting terminal 7 and the connecting terminal 10 of the pixel electrode are respectively opposed to each other via an anisotropic conductive film, and heated and pressurized. The two are connected by thermocompression bonding.

As described above, in the liquid crystal display device according to the present invention, the mounting portion of the liquid crystal display panel 1 connects the connection terminals 7 of the plurality of pixel electrodes of the liquid crystal display panel 1 and the bus line 13.
The plurality of connection parts 14 are arranged in parallel, and the connection terminals 10 and 11 of the film carrier 9 are arranged and connected on these connection parts 7 and 14, so that the liquid crystal display panel There is no need to provide a crossover section such as multilayer wiring in one bus line section, and simple and highly reliable wiring becomes possible. Furthermore, during assembly, the force acting on the connection between the liquid crystal display panel 1 and the film carrier 9 is small due to the load of the film carrier 9, so even if the liquid crystal display panel 1 is increased in size, the connection will not break. . Note that when connecting a chip component such as a chip capacitor as a noise filter to the bus line 13, if the bus line 13 is made of a material that is difficult to solder, such as aluminum, a film carrier 9 made of copper may be used. It is only necessary to solder the bus line, and therefore there is no need to plate the bus line, so productivity can be improved.

FIG. 2 shows the main part configuration of another embodiment, in which the wiring connected to the input lead of the IC 8 is separated and routed to both the left and right sides of the IC 8 on the film carrier 9. The vertical dimension of the device has been reduced to enable compact mounting.

FIG. 3 shows a third embodiment, in which the connecting portion 14 of the bus line 13 and the connecting terminal 11, and the connecting portion between the connecting terminal 7 and the connecting terminal 10 of the pixel electrode are connected to the front side of the liquid crystal display panel 1. The film carrier 9 is bent in a U-shape along the side surface of the liquid crystal display panel 1, and the film carrier 9 is fixed to the liquid crystal display panel 1 so that the IC 8 is located on the back side of the liquid crystal display panel 1. It is something. By arranging it in this way, the device can be further miniaturized.

Note that in a liquid crystal display device in which a thin film transistor is formed in a portion of the liquid crystal display panel, the source electrode and drain electrode are formed of aluminum, so if the bus line 13 is also formed of aluminum at the same time, workability will be improved. It turns out. On the other hand, if the conduction resistance of the bus line 13 increases, it will have a negative effect on the image. It is necessary to set the thickness of line 13 to 0.9 μm,
If the film thickness is within this range, there will be no problem in forming the source electrode and the drain electrode at the same time.

[0011]

As described above, the liquid crystal display device according to the present invention includes a plurality of connection terminals for supplying driving voltage to pixel electrodes, a connection portion formed along the connection terminals, and a bending portion extending from the connection portion. A liquid crystal panel with a bus line in which a plurality of these connection parts and lead parts are formed in parallel, an input connected to the connection terminal of the pixel electrode and the connection part of the bus line. Equipped with a circuit board that has leads and output leads and is equipped with electronic components that supply drive voltage to the pixel electrodes, which improves productivity, reduces device size, reduces material costs, and improves connection reliability. This has the effect of improving

[Brief explanation of the drawing]

FIG. 1 is a plan view showing essential parts of a liquid crystal display device according to an embodiment of the present invention.

FIG. 2 is a plan view showing essential parts of a liquid crystal display device according to another embodiment of the invention.

FIG. 3 is a sectional view showing essential parts of a liquid crystal display device according to a third embodiment of the invention.

FIG. 4 is a perspective view showing the configuration of a conventional liquid crystal display device.

FIG. 5 is a cross-sectional view showing a conventional liquid crystal display device.

[Explanation of symbols]

1. Liquid crystal display panel 2, 3 Glass plate 4 Sealant 5 Liquid crystal 6 Polarizing plate 7 Pixel electrode connection terminal 8.LCD drive IC 9 Film carrier 10, 11 Wiring connection terminal 13 Bus line 14 Bus line connection 15 Bus line lead part

Claims (1)

[Claims] 1. A plurality of pixel electrodes formed by coating a transparent conductive film on a transparent substrate, a plurality of connection terminals extending from these pixel electrodes and supplying a driving voltage to each of the pixel electrodes, and It consists of a connection part formed along the connection terminal and a lead part bent from this connection part and formed on the outer periphery of the plurality of connection terminals, and a plurality of the connection parts and lead parts are formed in parallel. A liquid crystal display panel having a bus line, a plurality of input leads and output leads connected to the connection terminal of the pixel electrode and the connection part of the bus line, and an electronic component that supplies a driving voltage to the pixel electrode. A liquid crystal display device comprising a printed circuit board.