JP2612968B2 - Display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat type display device such as a thin film EL display, a plasma display and a liquid crystal display.

[0002]

2. Description of the Related Art FIG. 6 is a plan view showing the structure of a conventional thin film EL display device used as a display of a computer terminal, a communication device, a measuring device, and the like. FIG. 7 is a sectional view taken along the line VII-VII of FIG. FIG. 8 is a rear view of the thin film EL display device.

The display panel 21 is a panel for displaying an image, and is composed of a thin-film EL display element, and is fixed to a surface side of a base plate 22, which is a support plate, with an adhesive tape or an adhesive. In the thin film EL device, strip-shaped transparent electrodes are arranged in parallel on a glass substrate, a dielectric material is laminated thereon, an EL layer is further laminated thereon, and a dielectric material is further laminated thereon. It has a layered structure, on which strip-shaped back electrodes extending in a direction perpendicular to the transparent electrodes are arranged in parallel.

The hard printed wiring board 23 is a board on which an integrated circuit element (hereinafter referred to as a drive IC) 24 constituting a drive circuit for driving the display panel 21 is mounted. And one end thereof is fixed to the back side of the base plate 22 by an adhesive tape or a screw. For example, the above-described transparent electrodes extend as data-side electrodes on each of the upper and lower sides of the display panel 21, and the above-described back electrodes extend as scanning-side electrodes on each of the left and right sides. The driving ICs 24 associated with the sides are circuits for driving the data side electrodes, and the driving ICs 24 associated with the left and right sides are circuits for driving the scanning electrodes.

The drive IC 24 and the display panel 21, that is, the drive IC 24 and each electrode of the display panel 21 face the non-fixed end of the hard printed wiring board 23, that is, the end fixed to the base plate 22. Are electrically connected to each other via four printed wirings formed on the four flexible printed wiring boards 25 connecting the corresponding ends of the display panel 21 to the corresponding ends of the display panel 21.

Further, on the back side of the base plate 22, a timing control board 2 on which a control circuit for controlling the drive timing of the drive IC 24 is mounted.
6 is fixed by screws or the like.

FIG. 9 is a diagram showing a connection state of a flexible printed wiring board 25 connected between the display panel 21 and the rigid printed wiring board 23. Among them, FIG.
9B is a plan view of the connection state, and FIG. 9B is a cross-sectional view taken along the line IX-IX of FIG. 9A.

That is, the hard printed wiring board 23 is arranged so that the surface on which the drive IC 24 is mounted is oriented in the same direction as the surface of the display panel 21 and one end thereof is opposed to a corresponding side of the display panel 21. Originally, a flexible printed wiring board 25 is connected between the display panel 21 and the rigid printed wiring board 23 on the back side thereof. Thereafter, the connected flexible printed wiring board 25 is bent and deformed, and the other end of the hard printed wiring board 23, that is, the end opposite to the end to which the flexible printed wiring board 25 is connected is connected to the base plate 22. 7, the surface on which the driving IC 24 is mounted is moved to the display panel 2 as shown in FIG.
The hard printed wiring board 23 is fixed to the back surface of the base plate 22 in a state where the hard printed wiring board 23 is aligned in the same direction as the back surface of the base plate 22.

[0009]

However, as in the above-mentioned conventional thin film EL display device, the flexible printed wiring board 25 is bent and deformed, and the rigid printed wiring board 23 is attached to the back surface of the base plate 22 with an adhesive tape or the like. In this configuration, not only the fixing is uncertain, but also two sides adjacent to the display panel 21, for example, two sides corresponding to the upper side and the right side.
An overlapping portion occurs between the two hard printed wiring boards 23, and the following problems occur. That is, the drive IC 24 which is lowered at such an overlapped portion
Repair work becomes impossible.

Further, since the two hard printed wiring boards 23 on which the driving ICs 24 are mounted are overlapped with each other, it is difficult to reduce the thickness of the display device.

In order to avoid the overlap with the configuration of the conventional example, the arrangement of the drive ICs 24 on the rigid printed wiring board 23 must be shifted from the arrangement of the electrodes of the display panel 21 in an unreasonable arrangement. In practice, such an arrangement cannot be adopted.

Accordingly, an object of the present invention is to fix a rigid printed circuit board reliably with a simple structure, to easily repair a drive circuit mounted on the rigid printed circuit board, and to reduce the thickness of the device. It is to provide a display device which enables the above.

[0013]

The present invention provides a quadrilateral display panel having a display element and fixed to a surface of a support plate,
A hard printed wiring board on which a drive circuit element for driving the display panel is mounted, and one end which is associated with a side of the display panel and is bent and deformed from an end of the support plate to a back surface. A flexible printed wiring board for electrically connecting a drive circuit element of the hard printed wiring board to the display panel by connecting a portion to one side of the display panel and another end to one end of the rigid printed wiring board. In the display device including, the one end to which the flexible printed wiring board of the hard printed wiring board is connected,
Inserting into the engagement holding portion provided on the back side of the support plate,
The display device is characterized in that the rigid printed wiring board is fixed to the supporting plate by bending stress of the flexible printed wiring board acting on the engagement holding portion.

[0014]

According to the present invention, the rigid printed circuit board inserted into the engagement holding portion provided on the back surface of the support plate is connected to the rigid printed circuit board and is bent and deformed. It is reliably fixed to the engagement holding portion by the bending stress.

Further, the position of the drive circuit element mounted on the rigid printed wiring board is set to an area outside the one end of the rigid printed wiring board inserted into the engagement holding portion on the back surface of the supporting plate. By doing so, it is possible to prevent the drive circuit element portions from overlapping between the hard printed wiring boards corresponding to the adjacent sides of the display panel.

[0016]

FIG. 1 is a plan view showing a schematic structure of a thin film EL display device according to an embodiment of the present invention, and FIG. 2 is a sectional view taken along the line II--II in FIG. FIG. 3 is a rear view of the thin-film EL display device.

The quadrilateral display panel 1 is a panel for displaying an image by a display element formed on the surface thereof, is composed of a thin-film EL element, and is provided with an adhesive tape or an adhesive on the surface side of a base plate 12 which is a supporting plate. Fixed by In the thin film EL device, strip-shaped transparent electrodes are arranged in parallel on a glass substrate, and a dielectric material is laminated thereon,
An EL layer is further laminated thereon, and a dielectric material is further laminated thereon to form a three-layer structure, on which a strip-shaped back electrode extending in a direction orthogonal to the transparent electrode is arranged in parallel. .

The hard printed wiring board 3 is a drive IC which constitutes a drive circuit element for driving the display panel 1.
4 are mounted on the substrate, and four substrates are provided corresponding to each side of the display panel 1. The drive IC 4 and the display panel 1 are electrically connected to each other via printed wirings formed on four flexible printed wiring boards 5 prepared in association with each side of the display panel 1. The timing control board 6 is a board on which a control circuit for controlling the drive timing of the drive IC 4 is mounted, and is fixed to the back surface of the base plate 12 with screws or the like.

In this embodiment, a support frame 12a having a groove 12b for supporting the rigid printed wiring board 3 is integrally formed on both right and left sides of the base plate 12, and
On the back side of the base plate 12, each of the support frames 12a
The nails 12c for inserting one end of the hard printed wiring board 3 are formed integrally with each other at a position opposed to.
In this embodiment, a modified PPO resin is used as a material of the base plate 12.

In the hard printed wiring board 3 corresponding to both the left and right sides of the display panel 1, the display panel 1 corresponds to the position in which the drive IC 4 mounting surface is arranged in the same direction as the surface of the display panel 1. One end facing one side and one corresponding side of the display panel 1 are connected by a flexible printed wiring board 5, and the flexible printed wiring board 5 extends from the side of the base plate 12 to the back surface. Is bent so that the connection end of the hard printed wiring board 3 corresponds to the corresponding claw 12 of the base plate 12.
c.

FIG. 4 is a diagram showing a connection state of a flexible printed wiring board 5 connected between the display panel 1 and the rigid printed wiring board 3. As shown in FIG. 4A is a plan view of the connection state, FIG. 4B is a cross-sectional view taken along the line IV-IV of FIG. 4A, and FIG.
The cross-sectional views in which the flexible printed wiring board 5 is bent and deformed from the state shown in FIG.

That is, the hard printed wiring board 3 is arranged such that the surface on which the drive IC 4 is mounted is aligned in the same direction as the back surface of the display panel 1 and one end thereof is opposed to a corresponding side of the display panel 1. Originally, the flexible printed wiring board 5 is connected between the end of the back surface of the display panel 1 and the end of the hard printed wiring board 3 on the side of the drive IC 4 on the side facing the display panel 1. Thereafter, the hard printed wiring board 3 is rotated by half a turn about the connection end 5a so that the surface on which the drive IC 4 is mounted faces upward, as indicated by an arrow R, and the connection end 5b is located on the back side of the base plate 12. , The flexible printed wiring board 3 is bent and deformed from the side to the back of the base plate 12.

FIG. 5 is a cross-sectional view showing a state during the step of bending and deforming the flexible printed wiring board 5 described above. When the flexible printed wiring board 5 is bent and deformed in this manner, when the distal end portion on the connection end 5b side indicated by the reference symbol H in FIG. A bending stress is applied to the flexible printed wiring board 5 in the direction indicated by the arrow Q.

The rigid printed wiring board 3 has its connection end 5b side finally inserted into the corresponding claw 12c of the base plate 12, and its opposite non-connection end side engages with the groove 12b of the support frame 12a. Let me do. The bending stress applied in the state of FIG. 5 is applied in the direction indicated by the arrow F and the direction indicated by the arrow G in FIG. 2 in this holding state, so that the rigid printed wiring board 3 is formed by the claw 12c of the base plate 12 and the support frame 12a. It is securely fixed to the base plate 12.

Here, a modified PPO resin capable of elastic deformation to some extent is used as a material of the base plate 12 in order to facilitate the work of inserting the hard printed wiring board 3 into the claws 12c and the support frame 12a. An elastically deformable resin such as the above-mentioned modified PPO resin may be used only for the support frame 12a and the nail 12c.

The mounting surface of the drive IC 4 on the left and right rigid printed circuit boards 3 mounted in this manner is shown in FIG.
As shown in (1), they are aligned in the same direction as the surface of the display panel 1. Therefore, the position of the drive IC 4 on the rigid printed wiring board 3 is determined in advance by the base plate 12 at the time of design.
Can be arranged in a region exposed to the outside from the back surface of the substrate.

On the other hand, the hard printed wiring boards 3 corresponding to the upper and lower sides of the display panel 1 are attached to the base plate 12 by the same configuration as the conventional case shown in FIGS. Therefore, the surface on which the driving IC 4 is mounted faces in the same direction as the rear surface of the display panel 1 as shown in FIG. 3, and the driving IC 4 is located in the rear surface region of the base plate 4. The left and right driving ICs 4 located outside do not overlap.

In the above embodiment, the rigid printed wiring board 3 corresponding to the upper and lower sides of the display panel 1 has the same support structure as that of the conventional example. May be fixed by the same support structure as the rigid printed wiring board 3 corresponding to both the left and right sides.

Although the present embodiment has been described with respect to an example in which a substrate is connected to two opposing sides, the concept of the present embodiment can be applied to a case where only one side is connected. Further, the same applies to the case where a plurality of substrates are used on one side, and the support structure of this embodiment can be applied to each substrate.

In this embodiment, a thin-film EL display device has been described as an example. However, the present invention is not limited to this and can be applied to a display device such as a plasma display or a liquid crystal display device.

[0031]

As described above, according to the display device of the present invention, the rigid printed wiring board is inserted into the engagement holding portion provided on the back surface of the support plate, and is connected to the rigid printed wiring board and bent and deformed. Since the rigid printed wiring board is configured to be held by the engagement holding portion by the bending stress of the flexible printed wiring board, the rigid printed wiring board can be securely fixed to the support plate by a simple configuration.

Further, the position of the drive circuit element mounted on the rigid printed wiring board is set to an area outside the one end of the rigid printed wiring board inserted into the engagement holding portion on the back surface of the supporting plate. This makes it possible to avoid overlapping of the drive circuit element portions between the hard printed wiring boards corresponding to the adjacent sides of the display panel.

[Brief description of the drawings]

FIG. 1 is a plan view showing a schematic configuration of a thin film EL display device according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view taken along the line II-II in FIG.

FIG. 3 is a rear view of the thin-film EL display device according to the embodiment.

FIG. 4 is a diagram illustrating a connection state of a flexible printed circuit board in the thin-film EL display device according to the embodiment.

FIG. 5 is a diagram illustrating a state in the middle of a bending deformation step of the flexible printed wiring board in the thin-film EL display device according to the embodiment.

FIG. 6 is a plan view showing a schematic configuration of a conventional thin film EL display device.

FIG. 7 is a sectional view taken along section line VII-VII of FIG. 6;

FIG. 8 is a back view of a conventional thin film EL display device.

FIG. 9 is a diagram showing a connection state of a flexible printed circuit board in a conventional thin film EL display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Display panel 3 Rigid printed wiring board 4 Drive IC 5 Flexible printed wiring board 12 Base plate 12a Support frame 12b Groove 12c Claw

Claims (1)

(57) [Claims] 1. A quadrilateral display panel having a display element and fixed to a surface of a support plate, a hard printed wiring board on which a driving circuit element for driving the display panel is mounted, and a display panel of the display panel. Corresponding to the side, the one end is connected to one side of the display panel and the other end is connected to one end of the rigid printed wiring board by bending and deforming from the end of the support plate material along the back surface. And a flexible printed circuit board for electrically connecting a drive circuit element of the hard printed circuit board to a display panel, wherein one end of the rigid printed circuit board to which the flexible printed circuit board is connected is connected. Into the engagement holding portion provided on the back side of the support plate, and the rigid printed wiring board is turned into the support plate by the bending stress of the flexible printed wiring board acting on the engagement holding portion. A display device characterized by being fixed.