JP2573243B2 - Display device - Google Patents

Description

The present invention relates to a display device such as an XY matrix type liquid crystal display device, and more particularly to a connection structure between a display panel and a driving integrated circuit element. Regarding improvement.

(Prior 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, so-called tape automated bonding (TA) is used to connect the liquid crystal display panel to the driving integrated circuit element.
B) Technology is used. 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.

(Problems to be Solved by the Invention) 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, 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 direction and the Y direction.
It cannot be driven by one driving integrated circuit element. For this reason,
For example, in the Y direction, the electrode terminals are divided into two groups of 120 and 100 electrode terminals, and two driving integrated circuit elements are used, and TA is used.
The display panel and the driving integrated circuit element are connected by the B technology. In this case, two integrated circuit elements having 120 drive terminals are used, one is a flexible substrate having 120 external connection terminals, and the other is a flexible substrate having 100 external connection terminals (the remaining 20 integrated circuit elements). Are not used) and are connected to the display panel.

By the way, in such a case, two types of flexible substrates are required, the type of the flexible substrate needs to be managed, and there is a problem that an error easily occurs during mounting.

In addition, if a dedicated drive integrated circuit element 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 element, it is possible to reduce the cost by mass production if it is made general-purpose rather than dedicated to a specific model. 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, it is common to use two integrated circuit elements having, for example, 120 drive terminals and use 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 flexible substrate.

[Configuration of the Invention] (Means for Solving the Problems) In the present invention, the display panel has a dummy electrode terminal that is not connected to an internal electrode, and has the same flexible type on which the same type of driving integrated circuit element is mounted. A plurality of substrates are provided, and at least one of the plurality of external connection terminals of the flexible substrate is connected to a dummy electrode terminal of the display panel.

(Operation) 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.

(Example) The present invention will be described in detail with reference to Fig. 1 showing an example.

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) x 2
20 (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. Substrate 2 is X
A signal electrode and a scanning electrode are formed in a -Y matrix, and a pixel electrode is provided at an intersection of the signal electrode and the scanning electrode via a thin film transistor (TFT). 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 arranged on the upper and lower sides of the substrate 2 so as to be distributed 240 pieces each. Further, the electrode terminal 6 of the scanning electrode is arranged on the left side of the
And two electrode terminal groups 6a and 6b.
Further, a dummy electrode terminal 6c which is not connected to the 20 scanning electrodes is provided below the electrode terminals 6a and 6b. The dummy electrode terminals 6c 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 drive integrated circuit elements 7a and 7b for scanning have 120 drive electrodes and are 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. Inner leads (not shown) of the flexible substrates 8a and 8b are connected to electrode terminals of the integrated circuit element, and outer leads (external connection terminals) (not shown) are electrode terminals 6a, 6b and 6c of the liquid crystal display panel 1. Connected to Integrated circuit element 7a
Is connected to the 120 electrode terminals 6a connected to the internal electrodes. Further, the flexible circuit board 8b on which the integrated circuit element 7b 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 connected to the flexible substrates 11a, 11b, and 1d.
This is mounted on 1c and 11d, and this is connected to the electrode terminal 5 of the display panel. In this case, if four integrated circuit elements having 120 drive electrodes are used, just 480 internal electrodes can be driven, and therefore, dummy electrode terminals are not provided unlike scan electrode terminals.
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 in which a dummy electrode terminal is added to the scanning electrode terminal side has been described. 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.

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.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a main part of an embodiment of the present invention. 1 Display panel 2, 3 Substrate 5 Signal electrode terminal 6a, 6b Scan electrode terminal 6c Dummy electrode terminal 7a, 7b Driving integrated circuit element 8a, 8b Flexible substrate

Claims (1)

(57) [Claims] A plurality of driving integrated circuit elements, a plurality of flexible substrates for individually mounting the driving integrated circuit elements,
A display device comprising: a display panel having a plurality of electrode terminals connected to external connection terminals of a flexible substrate; wherein the display panel has dummy electrode terminals not connected to internal electrodes; It has a plurality of identical flexible substrates on which integrated circuit elements are mounted, and at least one of the plurality of external connection terminals of one flexible substrate is connected to a dummy electrode terminal of a display panel. Display device.