JP2656459B2 - Display device manufacturing method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device such as an XY matrix type liquid crystal display device, and more particularly to an improvement in a connection structure between a display panel and a driving integrated circuit element.

[0002]

2. Description of the Related Art Generally, in an XY matrix type liquid crystal display panel, the number of electrode terminals increases as the number of display pixels increases. For this reason, a so-called tape automated bonding (TAB) technique is used for connecting the liquid crystal display panel to the driving integrated circuit element. That is, the individual driving integrated circuit elements are individually mounted on a flexible substrate, and the external connection terminals of the flexible substrate are connected to the electrode terminals of the display panel.

[0003]

As an integrated circuit element for driving a display panel having a large number of electrode terminals, one capable of driving a large number of electrodes by one is preferable. However, the number of electrode terminals of the integrated circuit element cannot be increased unnecessarily due to package technology and the like, and at present, a driving integrated circuit element having about 120 drive electrodes is practically used.

Now, it is assumed that the number of pixels of the XY matrix type liquid crystal display panel is 480 (X direction) × 220 (Y direction). In such a case, the number of electrodes is large in both the X and Y directions, and both cannot be driven by one driving integrated circuit element. For this reason, for example, in the Y direction, 120
The display panel is divided into two groups of electrode terminals, i.e., 100 and two, and two driving integrated circuit elements are used, and the display panel and the driving integrated circuit elements are connected by TAB technology. At this time, 120
And two integrated circuit elements having one drive terminal.
A flexible substrate having 0 external connection terminals and another flexible substrate having 100 external connection terminals (the drive terminals of the remaining 20 integrated circuit elements are not used) are connected to the display panel.

[0005] In such a case, two types of flexible substrates are required, the types of the flexible substrates need to be managed, and there is a problem that errors are likely to occur during mounting.

If a dedicated integrated circuit device for driving having 110 drive terminals is newly created, the above-mentioned problem is eliminated, but there is a problem that the production cost is increased. In particular, as an integrated circuit device,
A general purpose can reduce the cost by mass production. For this reason, it is desirable that the present invention can be used not only for a display panel having 220 electrodes in the Y direction but also for various display panels such as 230 and 240 electrodes. For this reason, as described above, for example, an integrated circuit element having 120 drive terminals
It is common to use two different flexible substrates.

According to the present invention, when mounting a driving integrated circuit element on a display panel, a general-purpose driving integrated circuit element that can be used for other models can be used instead of a dedicated driving integrated circuit element. It is an object to provide a display device that does not require a plurality of types of flexible substrates.

[0008]

According to the present invention, there is provided a method of manufacturing a display device, comprising: a first step of forming an electrode terminal on a substrate of a display panel for extracting an internal electrode of the display panel to the outside; In a method for manufacturing a display device comprising a second step of connecting external connection terminals of a plurality of flexible substrates each individually mounted with an integrated circuit for driving a panel to an electrode terminal of the display panel, the first step includes: Forming a dummy electrode that is not connected to the internal electrode on the substrate of the display panel, wherein the second step includes forming a part of an external connection terminal of at least one flexible substrate of the plurality of flexible substrates. A step of connecting to the dummy electrode.

[0009]

Since the dummy electrode terminals that are not connected to the internal electrodes are formed on the display panel, the same flexible substrate can be used. The driving terminal of the driving integrated circuit element connected to the dummy electrode terminal is not connected to the internal electrode of the display panel, and does not cause any trouble. Moreover, since the dummy electrode terminals are connected to the external connection terminals of the flexible substrate, the connection strength between the flexible substrate and the display panel can be increased, and the reliability is improved.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail with reference to FIG.

As the display panel 1, an active matrix type liquid crystal display panel was used. The number of pixels is 480 (X direction: signal side) × 220 (Y direction: scanning side). The liquid crystal display panel 1 has liquid crystal sandwiched between a pair of upper and lower substrates 2 and 3. On the substrate 2, signal electrodes and scanning electrodes are formed in an XY matrix, and a thin film transistor (TF
A pixel electrode is provided via T). The signal electrodes and the scanning electrodes, which are the internal electrodes, are drawn up and down and left of the substrate 2 in the figure, and are connected to the electrode terminals. The electrode terminals 5 of the signal electrodes are distributed above and below the substrate 2 by 240 lines. The electrode terminal 6 of the scanning electrode is arranged on the left side of the substrate 2 and is divided into two electrode terminal groups 6a and 6b of 120 and 100. The dummy electrode terminals 6c which are not connected to the 20 scanning electrodes below the electrode terminals 6a and 6b are formed at the same pitch as the electrode terminals 6a and 6b. Since these electrode terminals can be formed by the same process, no additional steps are required in manufacturing.

On the other hand, the scanning drive integrated circuit elements 7a,
7b has 120 drive electrodes and is mounted on the flexible substrates 8a and 8b. Here, the driving integrated circuit elements 7a and 7b are the same, and the flexible substrates 8a and 8b are also the same. The inner leads (not shown) of the flexible substrates 8a and 8b are connected to the electrode terminals of the integrated circuit element, and the outer leads (external connection terminals) (not shown) are connected to the electrode terminals 6a and 6a of the liquid crystal panel 1.
6b, 6c. The flexible substrate 8a on which the integrated circuit element 7a is mounted has the 120
Connected to the electrode terminals 6a. The integrated circuit element 7
The flexible circuit board 8b on which b is mounted is connected to both the 100 electrode terminals 6b connected to the internal electrodes and the 20 dummy electrode terminals 6c not connected to the internal electrodes.

Although not described in detail, the signal driving integrated circuit elements 10a, 10b, 10c, and 10d are mounted on the flexible substrates 11a, 11b, 11c, and 11d, and are mounted on the electrode terminals 5 of the display panel. Connecting. In this case, if four integrated circuit elements having the number of drive electrodes of 120 are used, just 480 internal electrodes can be driven, so that a dummy electrode terminal is not provided like a scan electrode terminal. To operate as a display device, a power supply, a control signal, a video signal, and the like are further applied from the opposite side of the flexible substrate to the display panel (not shown).

In the above-described embodiment, an example has been described in which a dummy electrode terminal is added to the scanning electrode terminal side. However, the present invention may be such that a dummy electrode is provided on the signal electrode terminal side. Further, dummy electrodes may be provided on both the scanning electrode terminal side and the signal electrode terminal side.

[0015]

According to the present invention, a dummy electrode terminal that is not connected to an internal electrode is formed on a display panel while using the same driving integrated circuit element and the same flexible substrate. Accordingly, the same drive integrated circuit element having high versatility can be used, and the cost can be reduced. Further, the flexible substrate is the same, and the type management is not required as compared with the case where two types are used, and erroneous connection does not occur when connecting to the display panel.

Further, it is not necessary to increase the number of steps when forming the dummy electrode terminals and connecting the electrode terminals of the flexible substrate and the dummy electrode terminals.

[Brief description of the drawings]

FIG. 1 is a diagram showing a main part of an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Display panel 2, 3 ... Substrate 5 ... Signal electrode terminal 6a, 6b ... Scanning electrode terminal 7a, 7b ... Driving integrated circuit element 8a, 8b ... Flexible substrate

Claims (1)

(57) [Claims] 1. A first electrode forming an electrode terminal for extracting an internal electrode of the display panel to the outside on a substrate of the display panel.
And a second step of connecting external connection terminals of a plurality of flexible substrates on which the integrated circuits for driving the display panel are individually mounted to electrode terminals of the display panel. In the first step, an electrode terminal connected to the internal electrode and a dummy electrode not connected to the internal electrode are formed on the substrate of the panel corresponding to the external connection terminal in the same step. > The step of performing, the second step, of the plurality of flexible substrates
Connecting a part of an external connection terminal of at least one flexible substrate to an electrode terminal connected to an internal electrode of the display panel, and connecting another part of the external connection terminal to the dummy electrode. A method for manufacturing a display device, comprising: