JP2006106781A - Liquid crystal display device and electronic appliance - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To decrease driving circuits of a liquid crystal display device to reduce the cost and the number of manufacturing steps, and to save a space for an electronic appliance mounting the liquid crystal device. <P>SOLUTION: A first liquid crystal cell and a second liquid crystal cell are connected to each other; the first liquid crystal cell is interposed by a first polarizing plate and a second polarizing plate; the second liquid crystal cell is interposed between the second polarizing plate and a third polarizing plate; and the second polarizing plate is disposed between the first liquid crystal cell and the second liquid crystal cell. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a multilayer liquid crystal display device and an electronic apparatus equipped with the liquid crystal display device.

  FIG. 7 shows an example of a conventional stacked liquid crystal display device of a driving liquid crystal cell. That is, in order to drive the first liquid crystal cell 1 and the second liquid crystal cell 2, a drive circuit is connected to each.

  However, since the conventional liquid crystal display device has a structure as shown in FIG. 7, two drive circuits 4 are required, resulting in an increase in cost and manufacturing man-hours.

  In addition, in an electronic device equipped with a conventional liquid crystal display device, two drive circuits are required, and space saving cannot be achieved.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a liquid crystal display device in which drive circuits are reduced, the cost is reduced, and the number of manufacturing steps is reduced. It is another object of the present invention to provide an electronic device that saves space.

  The liquid crystal display device of the present invention is a liquid crystal display device in which at least two liquid crystal cells each having a liquid crystal layer sandwiched between a pair of substrates arranged opposite to each other are stacked, and each of the liquid crystal layers is driven. The first liquid crystal cell and the second liquid crystal cell are connected, the first liquid crystal cell is sandwiched between the first polarizing plate and the second polarizing plate, and the second liquid crystal cell is the second polarizing plate. And the third polarizing plate, and the second polarizing plate is disposed between the first liquid crystal cell and the second liquid crystal cell.

  The liquid crystal display device of the present invention is characterized in that a twisted-aligned nematic liquid crystal is used for the liquid crystal layer.

  In the liquid crystal display device of the present invention, a first retardation plate is disposed between the first polarizing plate and the first liquid crystal cell, and between the second polarizing plate and the second liquid crystal cell. Is characterized in that a second retardation plate is arranged.

  The liquid crystal display device of the present invention is characterized in that the first liquid crystal cell and the second liquid crystal cell are connected by a flexible tape.

  An electronic apparatus according to the present invention includes the liquid crystal display device according to the present invention.

  According to the liquid crystal display device of the present invention, the first liquid crystal cell and the second liquid crystal cell are connected, the first liquid crystal cell is sandwiched between the first polarizing plate and the second polarizing plate, and the second liquid crystal cell The cell is sandwiched between the second polarizing plate and the third polarizing plate, and the second polarizing plate is disposed between the first liquid crystal cell and the second liquid crystal cell. The board will be shared. As a result, the number of drive circuits can be reduced, the price can be reduced, and the number of manufacturing steps can be reduced.

[Example 1]
FIG. 1 is a diagram showing a main part of a first embodiment of a liquid crystal display device according to the present invention.

  The first liquid crystal cell and the second liquid crystal cell are stacked. In the first liquid crystal cell 1, an upper electrode substrate 11 and a lower electrode substrate 12 are separated by a spacer 13 at a predetermined interval and sandwich a liquid crystal 14. The electrode wiring of the lower electrode substrate 12 is connected to the signal input terminal portion 16 of the upper electrode substrate 11 through the conductive agent 15. In the second liquid crystal cell 2, an upper electrode substrate 21 and a lower electrode substrate 22 are separated by a spacer 23 at a predetermined interval and sandwich a liquid crystal 24. The electrode wiring of the upper electrode substrate 21 is connected to the signal input terminal portion 261 of the lower electrode substrate 22 through the conductive agent 25. Another signal input terminal portion 262 is provided on the opposite side of the signal input terminal portion 261 of the lower electrode substrate 22. The signal input terminal portion 16 and the signal input terminal portion 262 are electrically connected by the flexible tape 3. A wiring 27 for connecting the signal input terminal portion 262 and the signal input terminal portion 261 is provided on the lower electrode substrate 22. A TCP (tape carrier package) 5 provided with a driver 4 for driving the liquid crystal cell 1 and the liquid crystal cell 2 is connected to the signal input terminal portion 261.

  FIG. 2 is a diagram showing a wiring state when the liquid crystal display device of FIG. 1 is developed in the direction a at the portion of the flexible tape. You can see the above connection.

  In the liquid crystal display device of the present invention, it is easy to make the driver 4 as one chip, but it is difficult in the conventional liquid crystal display device. The conventional liquid crystal display device requires a power supply unit for driving each driver, but this is not necessary in the present invention. As a result, the price can be reduced. In addition, the number of manufacturing steps can be reduced.

[Example 2]
Next, consider the case where the second liquid crystal cell is a dot matrix. FIG. 3 is a diagram showing a main part of a second embodiment of the liquid crystal display device according to the present invention. FIG. 4 is a diagram showing a wiring state when the liquid crystal display device of FIG. 3 is developed in the direction a at the portion of the flexible tape.

  The first liquid crystal cell and the second liquid crystal cell are stacked. In the first liquid crystal cell 1A, an upper electrode substrate 11A and a lower electrode substrate 12A are separated by a spacer 13A at a predetermined interval, and sandwich a liquid crystal 14A. The electrode wiring of the lower electrode substrate 12A is connected to the signal input terminal portion 16A of the upper electrode substrate 11A through the conductive agent 15A. In the second liquid crystal cell 2A, the upper electrode substrate 21A and the lower electrode substrate 22A are separated by a spacer 23A at a predetermined interval, and sandwich the liquid crystal 24A. A TCP 52A provided with a driver 42A for inputting a low waveform for driving the liquid crystal cell 1A and the liquid crystal cell 2A is connected to the signal input terminal portion 263A of the upper electrode substrate 21A. Further, a TCP 5A provided with a driver 4A for inputting a column waveform for driving the liquid crystal cell 1A and the liquid crystal cell 2A is connected to the signal input terminal portion 261A of the lower electrode substrate 22A. Further, another signal input terminal portion 262A is provided on the opposite side of the signal input terminal portion 261A of the lower electrode substrate 22A. The signal input terminal portion 16A and the signal input terminal portion 262A are electrically connected by the flexible tape 3A.

  In the conventional liquid crystal display device, four or three drivers are required, but in the liquid crystal display device of the present invention, the number of drivers is limited to two. The conventional liquid crystal display device requires a power supply unit for driving each driver, but this is not necessary in the present invention. As a result, the price can be reduced. In addition, the number of manufacturing steps can be reduced.

Example 3
FIG. 5 is a diagram showing a main part of an embodiment of the liquid crystal display device according to the present invention.

  In Example 2, the liquid crystal cell 1A and the liquid crystal cell 2A are sandwiched between the upper polarizing plate 61A and the lower polarizing plate 62A. In the liquid crystal 14A, the product Δn · d of the optical anisotropy Δn of the liquid crystal and the thickness d of the liquid crystal layer is 0.86 μm, and is twisted 240 degrees to the right by the optically active agent. The liquid crystal 24A uses the same base material as the liquid crystal 14A and is twisted 240 degrees to the left with an optically active agent. Further, the direction of the liquid crystal molecules in contact with the lower electrode substrate 12A of the first liquid crystal cell and the direction of the liquid crystal molecules in contact with the lower electrode substrate 21A of the second liquid crystal cell are substantially orthogonal.

  Then, in addition to the effect of the second embodiment, when the liquid crystal cell 1A is driven, an icon can be displayed. When the liquid crystal cell 2A is driven, a dot can be displayed.

Example 4
FIG. 6 is a diagram showing a main part of an embodiment of the liquid crystal display device according to the present invention.

  In Example 2, the liquid crystal cell 1A is sandwiched between the upper polarizing plate 63A and the lower polarizing plate 64A. The upper polarizing plate 63A is a red color polarizing plate. Further, the liquid crystal cell 2A is sandwiched between the upper polarizing plate 64A and the lower polarizing plate 65A. The liquid crystal 14A has a product Δn · d of the optical anisotropy Δn of the liquid crystal and the thickness d of the liquid crystal layer of 0.86 μm, and is twisted 240 degrees to the left by the optically active agent. The liquid crystal 24A is the same as the liquid crystal 14A. The retardation plate 71A is sandwiched between the upper electrode substrate 11A and the upper polarizing plate 63A, and the appearance color is set to be colorless. Further, the retardation plate 72A is sandwiched between the upper electrode substrate 21A and the upper polarizing plate 64A, and the appearance color is set to be colorless.

  Then, in addition to the effect of the second embodiment, when the liquid crystal cell 1A is driven, the icon display can be displayed in red and white, and when the liquid crystal cell 2A is driven, the dot display can be displayed in black and white. Was made.

Example 5
Also in Example 1, it carried out similarly to Example 3 and Example 4. The same effects as in Example 3 and Example 4 were obtained.
The same effect can be obtained by a reflection type using a reflection plate and a semi-transmission type using a semi-transmission reflection plate.
Example 6
The liquid crystal display device of Example 5 was incorporated into a mobile phone. Since it can be done with a single chip driver, it not only saves space, but also makes the controller circuit easier.

1 is a structural diagram of a main part of a liquid crystal display device according to an embodiment of the present invention. FIG. 2 is a structural diagram of a main part showing a state of wiring in FIG. 1. 1 is a structural diagram of a main part of a liquid crystal display device according to an embodiment of the present invention. FIG. 4 is a structural diagram of a main part showing a state of wiring in FIG. 3. 1 is a structural diagram of a main part of a liquid crystal display device according to an embodiment of the present invention. 1 is a structural diagram of a main part of a liquid crystal display device according to an embodiment of the present invention. FIG. 6 is a structural diagram of a conventional liquid crystal display device.

Explanation of symbols

1. First liquid crystal cell 11. Upper electrode substrate 12. Lower electrode substrate 13. Spacer 14. Liquid crystal 15. Conductive material 16. 1. Signal input terminal part First liquid crystal cell 21. Upper electrode substrate 22. Lower electrode substrate 23. Spacer 24. Liquid crystal 25. Conductive material 261. Signal input terminal 262. 2. Signal input terminal section Flexible tape Driver 5. TAB

Claims (5)

In a liquid crystal display device in which at least two liquid crystal cells each having a liquid crystal layer sandwiched between a pair of opposed substrates are stacked and each of the liquid crystal layers is driven,
The first liquid crystal cell and the second liquid crystal cell are connected,
The first liquid crystal cell is sandwiched between a first polarizing plate and a second polarizing plate, and the second liquid crystal cell is sandwiched between the second polarizing plate and a third polarizing plate, A polarizing plate is disposed between the first liquid crystal cell and the second liquid crystal cell. 2. The liquid crystal display device according to claim 1, wherein a twisted alignment nematic liquid crystal is used for the liquid crystal layer. A first retardation plate is disposed between the first polarizing plate and the first liquid crystal cell, and a second retardation plate is disposed between the second polarizing plate and the second liquid crystal cell. The liquid crystal display device according to claim 1, wherein the liquid crystal display device is arranged. The liquid crystal display device according to any one of claims 1 to 3, wherein the first liquid crystal cell and the second liquid crystal cell are connected by a flexible tape. An electronic apparatus comprising the liquid crystal display device according to any one of claims 1 to 4.

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