JP2007132970A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device in which the first display element 2 and the second display element 3 are disposed across a backlight 1 emitting light to both sides, wherein a flexible substrate 4 connected with a first display element 2 for transmitting a driving signal is made small in size, and display elements are made large in size and improved in impact resistance. <P>SOLUTION: The display device is constituted such that a flexible substrate 4 is folded back from a position which is not overlapped with the second display element 3 and is fixed to a cover body 8 which protects the second display element. Thereby, an outer connection part disposed on the flexible substrate can be arranged on a position which is not overlapped with a display device flat plane. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a display device capable of double-sided display in which two display elements are combined with one backlight that emits light from both front and back flat surfaces. Specifically, the present invention relates to a display device in which a substrate provided with an external connection portion for driving a display element is folded back so as not to overlap with a display element arranged on the back plane side and fixed to a cover body.

  2. Description of the Related Art A double-sided liquid crystal display device is known in which liquid crystal display elements are arranged on the front and back plane sides with backlights that emit light from both the front and back plane sides (see, for example, Patent Document 1).

In addition, a liquid crystal display element disposed on the front surface side of the backlight is a substrate provided with electronic components for driving liquid crystal, and a main unit in which a liquid crystal driving signal is connected so as to be able to transmit, the main unit, and the back of the backlight. In a double-sided light-emitting liquid crystal display device in which a liquid crystal display element arranged on a flat surface side is configured from a substrate to which a liquid crystal driving signal can be transmitted, a substrate having liquid crystal driving electronic components is arranged on the back surface of the backlight Is known (see, for example, Patent Document 2).
Japanese Patent Laying-Open No. 2005-43477 (second page, FIG. 1) Japanese Patent Laying-Open No. 2005-17790 (second page, FIGS. 2, 10 and 11)

  In a conventional double-sided liquid crystal display device, a substrate provided with electronic components for driving liquid crystal and a liquid crystal display element are arranged on the backlight back plane side. Therefore, under the present circumstances, the maximum plane size of the liquid crystal display element is determined by the plane size of the substrate disposed on the back plane side of the backlight. In order to increase the size of the liquid crystal display element without changing the size of the display device, downsizing of the substrate is an effective means, and various means such as reduction of electronic parts and high-density mounting have been adopted. However, there is a limit to the miniaturization of the substrate by such means, and the enlargement of the liquid crystal display element cannot be easily achieved.

  Furthermore, it is known that a substrate layout in which electronic components are arranged between a connection portion with a liquid crystal display element and an external connection portion is advantageous for downsizing the substrate. However, with such a layout, the distance between the connection portion of the liquid crystal display element and the external connection portion increases, and as a result, the external connection portion is disposed in the center direction of the liquid crystal display device. In order to solve this problem, a structure in which a part of the periphery of the external connection portion is bent and the external connection is disposed at a position that does not overlap the plane of the liquid crystal display device is used. However, a substrate corresponding to such a structure has a problem that the shape is complicated and the outer size tends to be large, which increases the cost.

  Therefore, the present invention has an object to provide a display device in which a liquid crystal display element disposed on the back plane side of the backlight is enlarged and disposed so that the external connection portion of the substrate does not overlap the display element at a low cost. .

  The display device of the present invention includes a first display element disposed on the front surface of the backlight, a second display element disposed on the back surface, a first substrate connected to the first display element so that a drive signal can be transmitted, A cover body for protecting the second display element is provided. The first substrate is arranged on the same plane as the second display element, and is folded back from a position where it does not overlap the second display element, and is fixed to the cover body.

  According to such a configuration, it is possible to simultaneously arrange the external connection portion of the first substrate at a position that does not overlap the display device plane and to reduce the size of the first substrate. Further, since the first substrate is fixed by the cover body, the rigidity is remarkably improved, and it is possible to prevent problems such as solder peeling of the electronic components such as connectors and disconnection of the pattern. Therefore, quality can be improved.

  Furthermore, the 2nd board | substrate connected so that a drive signal can be transmitted to a 2nd display element through the 1st display element is provided. The second substrate is pressed against the backlight by the folded first substrate.

  In the display device of the present invention, the first substrate is folded back at a position that does not overlap with the second display element, so that the external connection portion can be disposed at a position that does not overlap with the display element. Further, since it is not necessary to make the substrate into a complicated shape, it is possible to reduce the size and cost of the substrate, and at the same time to increase the size of the second display element. Furthermore, by fixing the first substrate to the cover body, the cover body substitutes for the function of the conventional reinforcing plate, so that an inexpensive configuration that does not require the reinforcing plate is achieved.

  In the display device of the present invention, a first display element and a second display element are provided with a backlight that emits light on both sides. Here, a non-self-luminous display element is usually used. A first substrate that transmits a drive signal is connected to the first display element. The first substrate is provided with an external connection portion that transmits a signal from the external substrate. Moreover, the cover body which protects a 2nd display element is provided. The first substrate is folded so as not to overlap the second display element and is fixed to the cover body.

  According to such a structure, the external connection portion of the first substrate can be arranged at a position that does not overlap the display device plane. In addition, the size of the second substrate can be increased simultaneously with the size reduction of the first substrate. Furthermore, since the first substrate is fixed to the cover body, a reinforcing plate for reinforcing the first substrate becomes unnecessary.

  More specifically, the first flexible substrate is configured to be folded back in the gap formed by the backlight and the cover body.

  Alternatively, the cover body is formed so as to have a step, and the gap formed between the backlight and the cover body is different between a portion facing the second display element and a portion where the first substrate is bent. If the gap formed by the backlight and the cover body in the portion where the first substrate is folded is smaller than the gap formed by the cover body and the backlight in the portion protecting the second display element, Space can be used effectively. On the other hand, the gap formed by the backlight and the cover body in the portion where the first substrate is folded is configured to be larger than the gap formed by the cover body and the backlight in the portion protecting the second display element. In this case, even when an electronic component having a large height is mounted on the first substrate, the electronic components can face each other on the folded inner surface.

  Further, the external connection portion for transmitting a signal from the external substrate can be arranged on the first flexible substrate so as not to overlap the backlight.

  Furthermore, the second flexible substrate is connected to the first display element and the second display element and transmits a drive signal from the first display element to the second display element. The folded portion of the first flexible substrate is pressed against the backlight.

  Hereinafter, embodiments using a liquid crystal display element as a display element will be described with reference to the drawings.

  The liquid crystal display device of the present embodiment will be described with reference to FIG. As shown in the figure, a first liquid crystal display element 2 and a second liquid crystal display element 3 are arranged with a backlight 1 emitting light on both sides. A signal from the external substrate 12 is supplied to the first liquid crystal display element via the external connection portion 11 and the first flexible substrate 4. A liquid crystal driving IC 7 and an electronic component 10 are mounted on the first flexible substrate 4. The second liquid crystal display element 3 and the first liquid crystal display element 2 are electrically connected by a second flexible substrate 6. Then, a liquid crystal drive signal is transmitted to the second liquid crystal display element 3 via the first liquid crystal display element 2 and the second flexible substrate 6. A first flexible substrate 4 is fixed to a cover body 8 that protects the second liquid crystal display element 3. The cover body 8 and the first flexible substrate 4 are each provided with a guide hole. The guide hole 5 of the first flexible substrate 4 is aligned with the guide hole 9 of the cover body 8 so that the first flexible substrate 4 It is fixed to the cover body 8. The first flexible substrate is folded at the gap between the backlight 1 and the cover body 8 at a position not overlapping the second liquid crystal display element 3. As a result, the second flexible substrate 6 is sandwiched between the first flexible substrate 4 and the backlight 1. The first liquid crystal display element 2 and the second liquid crystal display element 3 are connected by a second flexible substrate 6, and the second liquid crystal display element 3 includes the first liquid crystal display element 2 and the second flexible display element. A drive signal is transmitted via the substrate 6. Furthermore, in the present embodiment, a stack type connector is mounted on one end side of the first flexible substrate 4 and functions as the external connection portion 11 connected to the external substrate.

  With this structure, the first flexible substrate 4 is firmly fixed with reference to the cover body 8 and the guide hole, so that a stable connection between the external substrate 12 and the first flexible substrate 4 is ensured. It becomes possible to do. Further, since the first flexible substrate 4 is folded as described above, the second liquid crystal display element 3 can be enlarged. Further, since the liquid crystal driving IC 7 and the electronic component 10 are all mounted on the first flexible substrate 4, it is not necessary to mount the liquid crystal driving IC 7 on the first liquid crystal display element 2, thereby reducing the cost of the display element itself. Is possible.

  The structure of the liquid crystal display device of this embodiment will be described with reference to FIG. The present embodiment is different from the first embodiment in that the liquid crystal driving IC 7 is mounted on the first liquid crystal display element 2. The first flexible substrate 4 is formed so as to be connectable to a connector mounted on the external substrate 12. That is, FIG. 2 shows a configuration in which the liquid crystal driving IC 7 and the connector as the external connection portion are not mounted on the first flexible substrate 4. Similar to the first embodiment, the first liquid crystal display element 2 and the second liquid crystal display element 3 are arranged with the backlight 1 interposed therebetween. The first flexible substrate 4 on which the external connection unit 11 and the liquid crystal driving electronic component 10 are mounted is connected to the first liquid crystal display element 2, and the first liquid crystal display element 2 and the second liquid crystal display element 3 are The two flexible boards 6 are electrically connected. The second liquid crystal display element 3 is protected by a cover body 8. The first flexible substrate 4 is folded back at a position that does not overlap the second liquid crystal display element 3 and is fixed to the cover body 8.

  According to such a structure, it is possible to freely arrange a connector provided on the external substrate 12 and an insertion substrate portion corresponding to the connector. Further, since the liquid crystal driving IC 7 is mounted on the first liquid crystal display element 2 and the first flexible substrate 4 is folded as described above, the size of the first flexible substrate 4 and the second liquid crystal are reduced. The display element 2 can be increased in size at the same time, and the cost of the substrate itself can be reduced. Furthermore, since the first flexible substrate 4 is fixed to the cover body 8, sufficient rigidity can be obtained. Furthermore, by adopting a structure in which the electronic components mounted on the first flexible substrate 4 face each other on the folded inner surface, a display device in which no external force is directly applied to the electronic components 10 can be realized.

  In the liquid crystal display device of this embodiment, the cover body is provided with a bent portion, the gap formed by the backlight 1 and the cover body 8 at the portion where the first flexible substrate 4 is folded, and the cover body 8 is the second body. The gap formed between the portion that protects the liquid crystal display element 3 and the backlight 1 is different. The configuration of the double-sided light emitting liquid crystal display device of this embodiment will be described with reference to FIGS.

  In the liquid crystal display device shown in FIG. 3, a bent portion 13 is provided in the cover body 8, and a gap formed between the backlight 1 and the cover body 8 in a portion where the first flexible substrate 4 is folded is a second liquid crystal display. It is configured so as to be smaller than the gap formed by the cover body 8 and the backlight 1 in the part that protects the element 3. Thereby, the space in the thickness direction can be used effectively. The main difference between the liquid crystal display device having the configuration shown in FIG. 3 and the first embodiment is that the sectional height of the folded portion of the second liquid crystal display element 3 and the first flexible substrate 4 is different. Here, the difference in height is caused by providing the bent portion 13 in the cover body 8. Since the other configuration is the same as that of the first embodiment, detailed description thereof is omitted.

  In the liquid crystal display device shown in FIG. 4, a bent portion 13 is provided in the cover body 8, and a gap formed between the backlight 1 and the cover body 8 in the portion where the first flexible substrate 4 is folded is a second liquid crystal display. It is configured so as to be larger than the gap formed by the cover body 8 and the backlight 1 in the part that protects the element 3. The main difference between the liquid crystal display device having the configuration shown in FIG. 4 and the liquid crystal display device of the second embodiment is that the gap between the cover body 8 and the backlight 1 in the folded portion of the first flexible substrate 4 is different. Here, the difference in height is caused by providing the bent portion 13 in the cover body 8. Since the other configuration is basically the same as that of the second embodiment, detailed description thereof is omitted. According to such a configuration, even when the height of the electronic component mounted on the first flexible substrate 4 is large, the electronic component can face each other on the folded inner surface.

  Since the double-sided display device can be reduced in size and thickness, and the display element can be increased in size, it can be applied to a foldable mobile phone. Furthermore, according to the double-sided display device of the present invention, characteristics excellent in substrate cost reduction and impact resistance can be realized at the same time, so that it can be applied to portable electronic devices whose cost is being reduced.

It is sectional drawing which shows typically the structure of the liquid crystal display device of this invention. It is sectional drawing which shows typically the structure of the liquid crystal display device of this invention. It is sectional drawing which shows typically the structure of the liquid crystal display device of this invention. It is sectional drawing which shows typically the structure of the liquid crystal display device of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Backlight 2 1st liquid crystal display element 3 2nd liquid crystal display element 4 1st flexible substrate 5 Guide hole 6 2nd flexible substrate 7 IC
8 Cover body 9 Guide hole 10 Electronic component 11 External connection portion 12 External substrate 13 Bending portion

Claims (6)

A first display element and a second display element arranged with a backlight interposed therebetween;
A first flexible substrate connected to the first display element so that a drive signal can be transmitted;
A cover body for protecting the second display element,
The display device, wherein the first flexible substrate is folded back at a position where it does not overlap the second display element, and is fixed to the cover body.   The display device according to claim 1, wherein the first flexible substrate is folded back in a gap formed by the backlight and the cover body.   The said cover body is formed with a level | step difference, The said space | interval differs in the part which the said 2nd display element opposes, and the part by which said 1st flexible substrate was bent. The display device described.   The external connection part for transmitting the signal from an external board | substrate is provided in said 1st flexible substrate, The said external connection part is arrange | positioned in the position which does not overlap with a backlight. 4. The display device according to any one of 3.   5. The driving electronic component is mounted on the first flexible substrate, and the first flexible substrate is folded so that the driving electronic component does not overlap each other. A display device according to claim 1. A second flexible substrate connected to the first display element and the second display element and transmitting a drive signal from the first display element to the second display element;
The display device according to claim 1, wherein the second flexible substrate is pressed against the backlight by the folded portion of the first flexible substrate.

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