JPS60129729A - Liquid crystal display device - Google Patents

Abstract

PURPOSE:To mount a small-sized and high density liquid crystal driving IC by mutually connecting a liquid crystal driving electrode to an electrode on a circuit substrate mounting the liquid crystal driving IC through a connecting substrate coated with conductive resin. CONSTITUTION:The liquid crystal driving IC13 is directly mounted on the insulating substrate 12 consisting of glass epoxy resin or the like, and after electrically connecting the IC13 with the substrate 12 by an electrode 14 and a wire bonding method or the like, the legality of the connection is tested and then the IC13 is sealed by resin 15. The connecting substrate consisting of a resin base film 16, a copper foil pattern 17 and a conductive resin layer 18 is placed on an electrode 19 of a liquid crystal panel and the electrode 14 of the substrate 12, and after positioning these electrodes 19, 14, both the electrodes 19, 14 are mutually connected on the same plane by a heated pressing plate 20. Consequently, the more small-sized and high density liquid crystal driving IC can be mounted as compared to a flat-packed IC.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to the structure of a large-capacity liquid crystal display device that displays information such as a large number of characters and pictures.

Conventionally, as a method of electrode connection between the display panel, drive circuit, and substrate of this type of dot matrix liquid crystal display device, as shown in FIG. 0) 3 is mounted on a rigid board 2 and pressed with a fixture 5, or as shown in Fig. 2, a rigid board on which a flat back MNJJXO8 is mounted. 7 and the panel 6 are electrically connected by means such as soldering or thermocompression bonding using a sheet-like connector 9 called a heat seal made of a flexible substrate or conductive resin printed in stripes, and further, as shown in FIG. It was folded on the back side of the panel as shown in (6).

However, such a structure is becoming unsuitable as a mounting structure for the liquid crystal drive x0 of dot matrix liquid crystal display devices, which have become larger in size and denser in recent years. That is, as shown in FIG. 1, the zebra rubber 4 generates an electric W! When continuing, the electrode pitch of the crystal and substrate will be affected by the pitch error of the substrate pattern due to the increase in scale. +0.5
The limit is 1RI+1. Also, when electrical connection is made using the sheet-like connector 9 as shown in Fig. 2, if the sheet-like lid is a flexible substrate, the electrode pitch will be 0.
5 fins is impossible, and in the case of heat sealing, the conductive material is formed into stripes by screen printing.
, 5m is the limit. However, market demands for dot matrix liquid crystal display devices include low power consumption,
Due to its thinness, it is used in office equipment, computer peripherals, LCD pocket TVs, and in the future wall-mounted TVs, which are strong enough to replace the current cathode ray tube TVs. 0.2 to 0.3 m+ is required.

Next, new problems are pointed out in the structures shown in Figures 1 and 2.

In other words, there is no problem if the LCD device functions as a reflective panel, but if it is made into a transmissive device, such as an LCD TV that competes with a CRT television, the substrate on which the driving IC is mounted must be a liquid crystal display. It is necessary to expand it in the plane direction with respect to the panel, but if the LCD driver is mounted on a flat package and mounted on the board, the board will be quite large.Q
It is not satisfactory as a display device for portable devices, especially pocket televisions.

The present invention has been made in order to eliminate these drawbacks, and the purpose of the present invention is to provide a mounting structure for a liquid crystal drive XO that improves the density and capacity of a liquid crystal panel and adopts a transmissive display method. It is.

The present invention will now be described in detail with reference to embodiments shown in the drawings. Third
In the figure, 11 is a liquid crystal puff and a liquid crystal drive electrode 19
2 is a resin layer substrate such as glass epoxy, and the drive 1013 is directly mounted on the substrate and electrically connected to the electrode 14 by a method such as a wire pad.
After completing the mounting check (including checking the electrical characteristics) of the metalwork 0 above, it is sealed with a resin 15. A connection board consisting of a resin base film 16, a copper foil pattern 17, and a conductive resin layer 18 is placed on the electrode 19 of the liquid crystal panel and the electrode 14 of the board 12, and each electrode and the electrode of the connection board are connected to each other on the connection board. After precise alignment through the base film 16 (thin, about 25 μm, made of a heat-resistant resin such as polyimide), the liquid crystal baffle 11 is interconnected on the same plane by applying a heated press plate. The gap 21 between the panel and the board 12 is l?m since the panel and the board are arranged in a plane.
The following shall apply.

Next, an example of the connection board will be explained with reference to FIG.
(L) (b) is an example consisting of a paste film 5, a copper foil pattern n, and a conductive resin container, and the conductive resin contains all six fine particles and the resin is in a semi-cured state. (C) uses a sheet-like conductive resin vessel, the conductive phase and fingers contain pieces of carbon fiber, and the resin is in a semi-cured state. In either case, after aligning the electrode pattern to be connected and the copper foil pattern 22, the semi-cured resin is cured under pressure by pressing with a heating press plate, and electrical conduction is established by contact between the conductive metal pieces in the resin. Therefore, the minimum pitch of connection electrodes is 0.2 to 0.4.
Cabinet is possible. The sheet-shaped conductive resin device shown in Fig. 4(C) is called an anisotropic conductive resin, and only the conductive resin portions between patterns on different substrates stacked on top of each other are electrically connected by pressing, and high KfaD is established between adjacent patterns on the same substrate. Hold resistance.

Next, another embodiment will be explained with reference to FIG.
C132 is a substrate on which a plurality of drive ICs are mounted, and has an electrode pattern 34 corresponding to the electrode 37 of the liquid crystal panel.
A connection board with a spreadable conductive resin, 36 is a flexible board for connection with a scanning circuit for matrix drive, and as described above, this example is a portable liquid crystal telescope display unit using a transmissive multi-matrix liquid crystal panel. Wriy,
It is something to do.

The principle of connection between the connection board 35, the liquid crystal panel 31, and the board 32 is the same as explained in FIGS. 3 and 4, but in this example, the connection is not simultaneous, but the drive IC is mounted first and the electrical characteristics are checked. The board 32 as a driver unit and the connecting board are bonded together, and then the connecting board 35 and the liquid crystal spring 31 are bonded together.
to join. In this example, the electrode pitch of the connection part is 0.25
m, about 200 high-density pieces, and 5 to 6 baskets of tsubo-chu, tsubo-chu, fuyuta-h, and shizu-permeable moisture denubrei, keeping the planar size small.

As described above, in the present invention, the liquid crystal and drive components are directly mounted on the substrate, the IC electrodes and the substrate pattern are connected, and the quality is inspected. (1) It is possible to realize a much smaller and higher density mounting of the liquid crystal driving device C than using a flat back mounted IC.

(4) It has remarkable effects such as making it possible to combine large-capacity, high-density transmissive liquid crystal displays into a small size in the plane direction.

[Brief explanation of the drawing]

1 and 2 (b) are cross-sectional views showing conventional examples with three different ILs, FIG. FIG. 4(a) is a cross-sectional view showing a connection board according to an embodiment of the present invention, and FIG. 4(C) and FIG. It is a sectional view of an example. 1.6, 11, 31., liquid crystal bell 3.8. Flat pack for driving liquid crystal O 13, 33., IC for liquid crystal driving 2, 7, 12, 32 degrees, LCD drive IC mounting board 16
, 25 , , Peyu Nu Film 17 , 22 . , copper foil patterns 18 , 23 , 24 , and conductive resin layer 35 . ,
Connection board and above Applicant: Seiko Electronics Industries Co., Ltd. 3rd. Figure 5゛

Claims (3)

[Claims] (1) Connect the liquid crystal drive electrodes of the liquid crystal display and the electrodes of the circuit board for the liquid crystal display on which the driver 0 is mounted to the wiring formed on the insulating film and the conductive wire covering the wiring. A liquid crystal display device characterized by electrical interconnection via a connection substrate made of a resin layer. (2) Connect the equal wiring of the connection board and the scanning drive electrode of the liquid crystal display, and the equal wiring of the connection board and the electrode of the drive circuit board.
2. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is connected to each other on a plane by pressing with a pressure plate after L-ZN positioning. (3) 6m motor C is directly attached to the circuit board.
! If! is characterized in that the pole and the substrate are bonded to each other.
f! 'F A liquid crystal display device according to claim 1.