JP2003100442A - Self-light emission display equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the connection reliability of a display panel and a drive circuit board in a self-light emission display. SOLUTION: The self-light emission display 1 is constituted with a self-light emission type display panel 100, which makes a display face, which counters the one main face of the board 101, a drive circuit board 200 equipped with a drive circuit, which drives this display panel 100, a flexible wiring board 400, of which the connection end is adhered to fix to the one main face of the board 101, and which transmits the signal from the above drive circuit board 200 to the above display panel 100, and a frame 300, which holds the above display panel 100 and the above drive circuit board 200 in an integrated manner. The above flexible board 400 is bent along with the side face of the above frame 300, and makes the above drive circuit board 200 arrange on the above display panel 100 at the non-displaying face side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-luminous display device, and more particularly to a self-luminous display device having a structure in which a drive circuit board is arranged on the non-display surface side of a display panel.

[0002]

2. Description of the Related Art Demand for a flat panel display device represented by a liquid crystal display device has rapidly increased by taking advantage of thinness, light weight and low power consumption of a CRT display. Among them, the active matrix type flat display device in which each display element is provided with a switch element can obtain good display quality without crosstalk between adjacent display elements, and thus can be applied to various displays such as portable information devices. It has come to be used.

In recent years, an organic electroluminescence (EL) display device has been actively developed as a self-luminous display capable of achieving a faster response and a wider viewing angle than a liquid crystal display device.

Each of these flat panel display devices comprises a display panel having a plurality of display elements arranged in a matrix and a drive circuit board for driving the display panel.

For example, in a transmissive liquid crystal display device,
A display panel is configured by holding a liquid crystal layer as a light modulation layer between an array substrate in which transparent electrodes are arranged in a matrix and a counter substrate in which counter electrodes are formed, and a non-display surface side of this display panel is provided with a surface light source via a surface light source. Arrange the drive circuit board.

On the other hand, a self-luminous display device such as an organic EL display device does not require the above-mentioned surface light source because it has a self-luminous layer as a light modulation layer.

[0007]

As described above, in a flat display device which does not require a surface light source, when the drive circuit board is bent and arranged on the non-display surface side of the display panel, the drive circuit board and the display panel are separated from each other. A stress is applied to the connecting portion of the flexible substrate to be connected in the peeling direction, and the connecting portion may be peeled off, which is a factor that significantly reduces reliability.

Further, since the flexible substrate has an extremely small radius of curvature at the bent portion, the wiring pattern may be broken at the bent portion and the flexible substrate may be broken.

The present invention has been made to solve the above technical problems, and an object thereof is to improve the connection reliability between the display panel and the drive circuit board.

[0010]

According to the present invention, there is provided a display panel comprising a plurality of self-luminous elements arranged in a matrix on one main surface of a substrate, the display surface having a surface facing the one main surface. A drive circuit board having a drive circuit for driving the self-luminous element, and a flexible wiring board having a connection end fixed to the one main surface of the board and transmitting a signal from the drive circuit board to the display panel. And a frame that integrally holds the display panel and the drive circuit board, wherein the flexible substrate is bent along a side surface of the frame, and the drive circuit board is provided. Is disposed on the non-display surface side of the display panel.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an organic EL display device 1 will be described as an example of a self-luminous display device according to an embodiment of the present invention in detail with reference to the drawings. FIG. 1 is a schematic exploded perspective view of the organic EL display device 1, and FIG. 2 is a schematic sectional view thereof.

The organic EL display device 1 is an organic EL panel 1
00 and an external drive circuit 2 for driving the organic EL panel 100
00 and a frame 300 that integrally holds them,
The external drive circuit 200 and the organic EL panel 100 are connected via a flexible wiring board 400.

FIG. 3 is a schematic plan view of the organic EL panel 100 and the external drive circuit 200. Organic EL panel 1
00 is the first electrode 102 on the supporting substrate 101 such as glass.
And the second electrode 10 arranged to face the first electrode 102.
3, a display region configured by arranging the display elements 105 having the organic light emitting layer 104 between these electrodes in a matrix, and a drive circuit that drives each display element 105 based on a signal from the external drive circuit 200. An array substrate 106 having a region and a sealing case 107 arranged on the non-display surface side of the organic EL panel 100. The array substrate 106 and the sealing case 107 are attached with a UV curable resin.

The display area of the organic EL panel 100 will be described in detail. In this embodiment, a 2.8-inch size display area is formed, and the video signal lines 108 and the scanning lines are formed on one main surface of the supporting substrate 101 having an insulating property. The signal lines 109 are arranged in a matrix, and an n-type TFT as a switching element 110, a video signal voltage holding capacitor 111, a p-type TFT as a drive control element 112, and an organic EL display element 105 are formed at the intersections thereof. .

The organic EL display element 105 has, for example, an ITO (Indium T) connected to the drive control element 112.
in oxide), a first electrode 102 formed of a light-transmissive conductive film, an organic light emitting layer 104 disposed on the first electrode 102, and an organic light emitting layer 104 that is opposed to the first electrode 102. And a second electrode 103 made of a light-reflective conductive film such as Ca. The organic light emitting layer 10
4 may be composed of a three-layer laminate of a hole transport layer formed commonly for each color, an electron transport layer, and a light emitting layer formed for each color, and is composed of two layers or a single layer functionally combined. May be done. In addition, in the present embodiment, the first electrode 102 is the anode and the second electrode 103 is the cathode. However, for example, an alkaline earth metal such as Ca is thinly formed so as to have a light-transmitting property to form the first electrode 102. , The second electrode 1
03 may have a laminated structure of a transparent conductive film and a metal layer such as Pd, and may serve as a cathode and an anode, respectively. In either case, it is possible to realize the bottom emission organic EL display device 1 having the support substrate 101 side as the display surface.

The drive area of the organic EL panel 100 is a signal line drive circuit 113 for driving the video signal line 108.
And a scanning line driving circuit 114 for driving the scanning signal line 109 are formed on the same substrate as the insulating substrate on which the switching element 110 is formed.

The switching element 110, the signal line driving circuit 113 and the scanning line driving circuit 114 are composed of thin film transistors using polycrystalline silicon for their semiconductor layers, and these are formed in the same process.

The signal line drive circuit 113 is the external drive circuit 2
00 is sampled to the corresponding video signal line 108, and the display element 105 is driven row by row by the switching element 110 controlled by the scanning line drive circuit 114.

Further, since the organic light emitting layer 104 is easily deteriorated when moisture adheres, the array substrate 106 and the sealing case 1 are
During 07, it is necessary to always keep a dry state.

Therefore, the sealing case 107 has, for example, Ba.
A desiccant 115 such as O is attached to prevent the organic light emitting layer 104 from being deteriorated by the adsorbed water inside the panel or the water infiltrated from the outside. The desiccant 115 is fixed to the protruding portion 107a of the sealing case 107 using a sealing film 116.

Further, the array substrate 106 and the sealing case 1
During 07, an inert gas such as nitrogen gas is introduced to maintain the dry state.

Next, the external drive circuit 200 will be described. The external drive circuit 200 receives the data output from the signal source 500 such as a personal computer and receives the data from the organic EL.
A controller unit 201 that performs digital processing such as generation of control signals for driving the panel 100 and rearrangement of digital display signals, a DA conversion circuit 202 that performs analog conversion of the digital display signals, and drives the organic EL panel 100. DC / DC converter 203 for generating power supply voltage
It consists of and.

The DC / DC converter 203, the controller unit 201, and the DA conversion circuit 202 are connected to the PCB (pr
The external drive circuit 200 and the organic EL panel 100 are connected by a flexible wiring board 400 which is disposed on the integrated circuit board 204 and has flexibility. This flexible wiring substrate 400 is configured by providing a base film, a plurality of metal wirings formed on the base film and arranged substantially parallel to each other, and a coverlay provided on a portion other than the connection terminals of the metal wirings. 1
00 and the flexible wiring board 400 are fixed to the main surface of the support substrate 101 by connecting the connection end of the flexible wiring board 400 by pressure bonding ACF, and the flexible wiring board 400 and the PCB 204 are connected by soldering. Done.

The organic EL display device 1 is constructed by integrally holding the organic EL panel 100 and the external drive circuit 200 connected to the organic EL panel 100 in a frame 300, and the external drive circuit 200 is connected to the frame 300. Is arranged on the non-display surface side of the organic EL panel 100 via.

More specifically, as shown in FIG. 2, organic E
The frame 300 is arranged on the non-display surface side of the L panel 100, and the protruding portion 107 a of the sealing case 107 is attached to the frame 30.
It fits in the 0 hole 300a. In addition, the flexible wiring board 400 is bent and the organic E
The PCB 204 is arranged on the back surface side of the L panel 100. At this time, the PCB 2 is not attached to the notch 300b of the frame 300.
It can be easily fixed by inserting 04.

Further, in the frame 300 at a position corresponding to the bent portion 400a of the flexible wiring board 400,
The side surface of the flexible wiring board 400 is continuously formed into a gentle curved surface, and by bending the flexible wiring board 400 along the curved surface, the radius of curvature of the bent portion 400a can be prevented from becoming extremely small, and the wiring pattern can be prevented from breaking. can do.

Although the side surface of the frame 300 can be made thinner as the thickness t becomes smaller, it is preferably 2 mm or more to prevent disconnection of the wiring pattern of the flexible wiring board 400. It is desirable that the curve of the cut line cut by a plane including a line has a semicircular shape with a radius of curvature of t / 2 or more. Here, a semicircular shape having a curvature radius of 1 mm or more is desirable, and
A surface including a normal line passing through the midpoint may have a circular shape or an elliptical shape that does not cross the arc of the curved surface.

As described above, in the organic EL display device 1 of the bottom emission type, by bending the flexible wiring along the frame 300, the bent portion 400 is formed.
The curvature of a can be controlled.

Further, by forming the side surface of the frame 300 into a shape having a gentle curved surface, breakage of the wiring pattern of the flexible wiring board 400 can be suppressed.

Further, by sandwiching the connecting portion between the organic EL panel 100 and the flexible wiring substrate 400 with the supporting substrate 101 and the frame 300, the stress generated by the twisting or bending of the flexible wiring substrate 400 applied to the connecting portion is reduced. It becomes possible to do.

Further, the protruding portion 107a of the sealing case 107
By fitting the holes into the holes 300a of the frame 300, an increase in module thickness can be suppressed. In addition, organic EL
With respect to the shake of the entire display device 1, the fitted part absorbs the shake and the mechanical strength of the module can be improved.

In the above embodiment, DC /
Although the case where the DC converter 203 is on the same PCB 204 for both the EL power source and the driving power source has been described, the power source circuit for the EL power source may be arranged on another substrate as shown in FIG.

As the screen size of the organic EL panel 100 increases, the EL drive current also increases. Therefore, by forming the power supply circuit on another substrate, adverse effects on the drive circuit can be suppressed.

The power from the external signal source 500 is input through the connector 205 arranged on the drive circuit PCB 204, and the drive PCB 204 outputs the EL power supply PCB 20.
Organic EL via flexible wiring board 400 via 6
It may be input to the panel 100 or the PCB 20 for EL power supply
An interface such as the connector 205 may be separately provided on the connector 6.

[0035]

According to the present invention, the mechanical strength of the connecting portion of the flexible wiring board for connecting the display panel and the drive circuit board is increased, and the connection reliability when the flexible wiring board is bent and used. Can be improved.

[Brief description of drawings]

FIG. 1 is a schematic exploded perspective view of an organic EL display device showing an embodiment of the present invention.

FIG. 2 is a schematic cross-sectional view of an organic EL display device showing an embodiment of the present invention.

FIG. 3 is a schematic plan view of an organic EL display device showing an embodiment of the present invention.

FIG. 4 is an organic EL showing another embodiment of the present invention.
It is a schematic exploded perspective view of a display device.

[Explanation of symbols]

1 ... Organic EL display device 100 ... Organic EL panel 101 ... Support substrate 105 ... Organic EL element 108 ... Video signal line 109 ... Scan signal line 110 ... Switching element 200 ... External drive circuit 300 ... frame 400: Flexible wiring board

Claims (3)

[Claims] 1. A display panel having a plurality of self-luminous elements arranged in a matrix on one main surface of a substrate, the display panel having a surface facing the one main surface as a display surface, and driving the self-luminous elements. A drive circuit board having a drive circuit, a flexible wiring board having a connection end fixed to the one main surface of the board and transmitting a signal from the drive circuit board to the display panel, the display panel and the drive A self-luminous display device comprising: a frame that integrally holds a circuit board, wherein the flexible substrate is bent along a side surface of the frame, and the drive circuit board is not displayed on the display panel. A self-luminous display device characterized by being disposed on the side. 2. The self-luminous display device according to claim 1, wherein a side surface of the frame is a curved surface having a curvature. 3. The self-luminous display device according to claim 1, wherein the self-luminous element is constituted by holding an organic EL layer between opposing electrodes.