JP2001255513A - Liquid crystal display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal display device wherein a liquid crystal display element, having flexibility and incorporated in which rigidity is imparted to facilitate handling and plural liquid crystal elements constitute a freely foldable (opening and closing) book system. SOLUTION: The liquid crystal display device is formed, by jointing the liquid crystal display elements 21 and 22, each having chiral nematic liquid crystals 43 interposed between a pair of sheet materials 41 and 42 to supporting substrates 25 and 26 having rigidity, respectively into a planar shape. The support substrates 25 and 26 are connected foldably with each other by a connecting material (an elastic member) 31 having flexibility.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display device, and more particularly to a liquid crystal display device having a display element in which liquid crystal is sandwiched between a pair of sheet members.

[0002]

2. Description of the Related Art In recent years, various systems for providing digitized information have been researched and developed as an alternative to the provision of information by printed matter. For example, a vending system that sells contents of an electronic book, or an electronic conferencing system that includes a master unit and a plurality of slave units and distributes meeting materials from the master unit to each slave unit.

[0003] In this type of system, it is preferable from the viewpoint of energy saving and the like that a display device for information used by a user or a conference participant be constituted by a liquid crystal display element having a memory property. For example, a liquid crystal display device having a memory property can produce a thin large screen of not only A4 size but also, for example, A3 size at low cost by sandwiching a chiral nematic liquid crystal between a pair of substrates (sheet materials). It is possible.

However, an element in which liquid crystal is sandwiched between a pair of sheet materials, particularly a so-called film liquid crystal display element using a resin film as a substrate, has flexibility in itself, is easily bent, and is inconvenient to handle. is there. In addition, when bent, the driving electrode may be bent at an acute angle and may be damaged. Further, there is a problem that the sheet material is distorted and the life is shortened. In particular, if liquid crystal exists in the bent portion, the liquid crystal has almost no elasticity, so it is unevenly distributed at the time of bending,
Distortion such as "wrinkles" is likely to occur in the sheet material.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal display device having a flexible liquid crystal display element having rigidity for easy handling. Another object of the present invention is to provide a liquid crystal display device having a simple structure and suitable for weight reduction.

Another object of the present invention is to provide, in addition to the above objects, a liquid crystal display device in which a plurality of liquid crystal display elements are foldable (openable and closable) in a book format.

[0007]

In order to achieve the above objects, a liquid crystal display device according to the present invention comprises a display element comprising a pair of sheet materials in which a liquid crystal having memory properties is sandwiched by a rigid support. It is characterized by being joined in a planar manner.

In the first liquid crystal display device having the above structure, a display element of a type in which liquid crystal, which can be mass-produced inexpensively, is sandwiched between sheet materials is joined to a rigid support in a planar manner. (Display area) does not bend or bend, does not impair visibility, and is convenient for handling.

Further, in a second liquid crystal display device according to the present invention, a plurality of display elements each having a liquid crystal having a memory property sandwiched between a pair of sheet members are each planarly joined to a rigid support. The support is characterized in that it is foldably connected by a flexible elastic member.

[0010] The second liquid crystal display device having the above structure has the advantages of the first liquid crystal display device and, for example, folds an A3-size device into a book-size A4 size and easily carries it. can do. In addition, since an elastic member is disposed in the bent portion and no liquid crystal exists, the liquid crystal is not bent and unevenly distributed, and does not adversely affect an image.

In the second liquid crystal display device, a scanning electrode for driving liquid crystal may be wired across a plurality of display elements via the bent portion. Alternatively, the scanning electrodes of each display element may be connected by a flexible substrate at the bent portion. Not only the drive circuit is simplified, but also a flexible elastic member is disposed at the bent portion, so that it has a flexible restoring force, and this portion is bent or distorted at an acute angle. The scanning electrode located at this portion is not damaged.

Further, the bent portion may have a spine portion that partially maintains a flat state when bent, and the spine portion may be provided with a display element including a liquid crystal having a memory property. Titles, author names, owner names, and the like can be easily and rewritably displayed on the spine.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the liquid crystal display device according to the present invention will be described below with reference to the accompanying drawings.

First Embodiment First, an example in which the present invention is applied to an electronic book device as a first embodiment will be described. This electronic book device 1 is, as shown in FIGS.
The liquid crystal display elements 21 and 22 are housed in a relatively rigid housing, which is composed of two first units 11 and two second units 12 on the left and right sides.

The first unit 11 has a built-in operation board 15 and a liquid crystal drive circuit.
7. A screen changeover switch 18 is provided. Also,
The second unit 12 has a built-in unit for loading a recording medium such as an optical disk or a memory card in which information to be displayed on the liquid crystal display elements 21 and 22 is stored.

The housings of the first and second units 11 and 12 are divided at a central portion, and connected by an elastic connecting member 31 so as to be freely bent. Then, the liquid crystal display elements 21 and 22 can be bent in a direction facing each other, and by folding the units 11 and 12 in this direction,
The elements 21 and 22 can be protected when not in use.

A bent portion A composed of the connecting member 31
Is a non-display area, and FIG. 3 shows a cross-sectional structure thereof. The rigid supporting substrates 25 and 26 constituting the housing and the liquid crystal display elements 21 and 22 including the light absorbing layer 39 are planarly joined by an adhesive or the like. The elements 21 and 22 each have a liquid crystal 43 sandwiched between two transparent resin sheet materials 41 and 42. As the liquid crystal 43, a chiral nematic liquid crystal exhibiting a cholesteric phase at room temperature is used.
Driving is performed by a simple matrix method with a pulse voltage applied from transparent electrodes (scanning electrode 45 and signal electrode 46) formed on the facing surface of.

The connecting member 31 is firmly adhered to the ends of the supporting substrates 25 and 26.

Between the sheet members 41 and 42, together with the liquid crystal 43, a sealing material 47 for partitioning the periphery of the display area of each of the elements 21 and 22 and sealing the liquid crystal 43 in the display area, and a liquid crystal 43
A resin columnar structure 48 for holding the thickness of the resin is sandwiched. Further, spherical spacers (not shown) may be scattered.

The chiral nematic liquid crystal performs display by switching between a selective reflection state (planar state) for reflecting light of a predetermined wavelength and a transparent state (focal conic state). When the liquid crystal is in a planar state, assuming that the helical pitch of the liquid crystal is P and the average refractive index is n, light having a wavelength λ = P · n is selectively reflected. In the focal conic state, the light is scattered when the selective reflection wavelength is in the infrared light region, and transmits visible light when the selective reflection wavelength is shorter than the infrared light region. Therefore, by setting the selective reflection wavelength in the visible light region and providing the light absorbing layer on the side opposite to the observation side of the element, it is possible to display the selectively reflected light in the planar state and display black in the focal conic state. . Also, by setting the selective reflection wavelength in the infrared light region and providing a light absorbing layer on the side opposite to the observation side of the element,
In the planar state, light having a wavelength in the infrared light range is reflected, but light having a wavelength in the visible light range is transmitted, so that black display is possible in the focal conic state, and white display is possible by scattering.

The electrodes 45 and 46 are strip electrodes that are orthogonal to each other, and drive the liquid crystal in a matrix by applying a predetermined pulse voltage with the intersection position as one pixel. After switching to the planar state or the focal conic state, the display state is maintained even when the supply of power is stopped, that is, it has a memory property.

Here, the bent portion A will be described. As shown in FIG. 3, the bent portion A is a non-display region where no liquid crystal exists, and is flexibly bent when bent because the elastic connecting member 31 is disposed. Therefore, the A3 size liquid crystal display device 1 with a double
It can be folded into four sizes, which is convenient for handling. In addition, each of the liquid crystal display elements 21 and 22 is
Since the display regions 5 and 26 are joined in a planar manner, the display area does not bend and the visibility of display is not impaired. Further, since there is no need to provide a hinge member for opening and closing the units 11 and 12, the configuration is simple and the screen can be easily arranged near the opening / closing portion of the housing.

FIG. 4 shows another example of the connecting member shown in FIG. 3 in which two thin ridges 32a are formed in parallel to each other. Connecting material 32 having
Is shown. When the units 11 and 12 are bent in the opposite direction (indicated by arrows c and c) from the normal bending direction, the ridges 32a come into contact with each other and prevent bending in the opposite direction.

FIG. 5 shows still another example of the connecting member shown in FIG. 3, showing a connecting member 33 having a bellows-like elasticity. . This connecting member 33 has good bending properties.

FIG. 6 shows still another example of the connecting member shown in FIG. 3, in which a block portion 34a functioning as a spine is provided at an intermediate portion. The connecting member 34 having elasticity is shown. In the connecting member 34, a title, an author's name, an owner's name, and the like can be written on the back of the block portion 34a, or a display paper can be pasted and used as a spine. The connecting member 31 can also be used as a spine in this way.

(Embodiment 2; see FIGS. 7 and 8) The electronic book device 2 according to the second embodiment includes liquid crystal display elements 21 and 22.
In order to drive the scanning electrodes 45 by one scanning drive IC 49, a flexible substrate 55 is disposed at the bent portion A. The element 21,
A plurality of electrode lines 56 for electrically connecting the 22 scanning electrodes 45 are arranged. Further, a voltage is applied to the signal electrode 46 from the signal drive IC 50 for each of the elements 21 and 22.

The connecting member 35 used in the electronic book device 2 is a thin plate-like elastic body and has good flexibility.
The surfaces of the units 11 and 12 are entirely covered with a cover 61 having a light-shielding property, and the cover 61 has windows 61a and 61b at portions corresponding to display areas.

The other structure is the same as the electronic book device 1
7 and 8, the same reference numerals as those in FIGS. 1 to 3 denote the same components.

In the second embodiment, since the driving IC for driving the scanning electrodes is shared by a plurality of display elements, the configuration of the apparatus can be simplified.

(Refer to Modification Example 1 of Second Embodiment, FIG. 9) FIG. 9 shows a structure 5 for reinforcement provided on the back surface of the connecting member 35 shown in FIG.
An example in which No. 1 is bonded is shown. The portion provided with the structural material 51 does not bend and can be used as a spine.

(Modification 2 of the second embodiment, see FIG. 10)
FIG. 10 shows an example in which a long structural member 52 having a triangular cross section is bonded to the back surface of the connecting member 35 shown in FIG. Structural material 52
Is provided, the connecting member 35 is reinforced, and misalignment of the units 11 and 12 can be prevented.

(Embodiment 3; see FIG. 11) In an electronic book device 3 of the third embodiment, the sheet material 41 on which the scanning electrodes are formed is shared by the liquid crystal display elements 21 and 22. In this case, the sheet material 41 has an area in which at least two elements 21 and 22 are combined, and the scanning electrodes are wired across the elements 21 and 22 via the bent portions. Further, the light absorbing layer 39 is also applied to the entire surface of the sheet material 41.

The other structure is the same as that of the electronic book device 2.
In FIG. 11, the same reference numerals as those in FIGS. 7 and 8 indicate the same components.

In the third embodiment, since the sheet material on which the electrodes are formed is shared by a plurality of display elements, the labor for connecting the plurality of display elements with a flexible substrate or the like can be omitted.

(Embodiment 4; see FIG. 12) The electronic book device 4 of the fourth embodiment is such that the sheet material 42 on which signal electrodes are formed is shared by the liquid crystal display elements 21 and 22. In this case, the sheet member 42 has an area in which at least two elements 21 and 22 are combined.

The other configuration is the same as that of the electronic book device 2.
In FIG. 12, the same reference numerals as those in FIGS. 7 and 8 indicate the same components.

In the fourth embodiment, since the formation direction of the electrode on the substrate shared by a plurality of display elements is along the bending line, the stress applied to the electrode in the bent portion is greatly reduced, and the damage is reduced. It is advantageous for prevention.

(Fifth Embodiment, see FIGS. 13 and 14) Fifth Embodiment
The electronic book device 5 according to the embodiment has a built-in liquid crystal display element 24 in a spine portion, and can display a title, an author name, an owner name, and the like. Other configurations are the same as those of the electronic book device 2, and FIGS.
The same reference numerals indicate the same components.

That is, as shown in FIG. 14, a liquid crystal display element 24 having a small width is provided between the liquid crystal display elements 21 and 22 of the first and second units 11 and 12. Support substrate 2
5 and 26 are connected by a plate-shaped connecting member 36 having elasticity, and a rigid structural member 28 is provided on a rear side portion corresponding to the element 24. The structural material 28 has a function of preventing the spine portion from bending, and is transparent and
Is made visible from the outside. Transparent structural material 2
8 is acrylic resin, polycarbonate resin, A
BS resin or the like can be used.

The surfaces of the units 11 and 12 are entirely covered with a cover 62 having a light shielding property.
In FIG. 2, windows 62a and 62b are formed at portions corresponding to the display area.

Therefore, in this electronic book device 5,
A portion where the supporting substrates 25 and 26 and the structural material 28 are interrupted is a bent portion A. The scanning electrodes of the three divided liquid crystal display elements 21, 22, 24 are electrically connected by a flexible substrate 55.

(Sixth Embodiment, see FIGS. 15 and 16) Sixth Embodiment
In the electronic book device 6 according to the embodiment, the first, second, and third units 11, 12, and 13 can be folded into a Z shape in three. Other configurations are the same as those of the electronic book device 2, and the same reference numerals in FIGS. 15 and 16 as those in FIGS.

That is, as shown in FIG.
1, 12, 13 are juxtaposed on one plane, and the supporting substrate 2
5, 26 and 27 are connected by a connecting member 37 having elasticity, and the connecting portion is a non-display area that can be bent. The folded state is as shown in FIG.

The surfaces of the units 11, 12, and 13 are entirely covered with a light-shielding cover 63. The cover 63 has windows 63a, 6a at portions corresponding to display areas.
3b and 63c are formed.

In the sixth embodiment, three units 11, 12, 23 including three display elements 21, 22, 23 are provided.
13 can be folded in three, so that the area when folded can be reduced to about 1/3 of that when the area is expanded. Accordingly, the amount of display information can be increased without impairing portability. For the same purpose, the number of folds may be further increased.

(Bending system, see FIGS. 17 and 18) FIG. 17 shows a first example of a bending system for supplying an information recording medium 71 to a user having an electronic book device. The information recording medium 71 is manufactured by a publisher or the like as an electronic information maker, and is connected to a store such as a convenience store, a bookstore, or a transportation station yard through a dedicated cable or a dedicated communication using radio waves or through a maintenance man. Be brought in. The user purchases or rents the desired recording medium 71 at the convenience store. The user may store desired information in an electronic book device owned by the user at a convenience store or the like.

FIG. 18 shows a second example of the bending system. In this vending system, an electronic information maker transfers information ordered by a user after viewing a catalog or the like to a user's personal computer 75 via a cable (telephone line). The user outputs the transferred information on the screen of the personal computer 75 or stores the information in the recording medium 71 owned by the user and inputs the information to the electronic book device via the recording medium 71. Also,
The electronic information maker that has received the order may directly deliver the recording medium 71 to the user.

(Other Embodiments) The liquid crystal display device according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the invention.

In particular, the liquid crystal display device according to the present invention is widely applicable not only to an electronic book device but also to a device used as a slave unit in an electronic conference system.

In each of the above embodiments, the liquid crystal display element is a monochrome or single liquid crystal cell using one liquid crystal cell.
Although the color display type is shown, a type in which a plurality of liquid crystal cells are stacked may be used. In particular, a full-color display is possible in a type in which liquid crystal cells that selectively reflect each of the three primary colors of light, R, G, and B, are stacked.

Further, regarding the structure of the liquid crystal display element,
Various structures other than the above embodiment can be adopted. As the liquid crystal, the above-described chiral nematic liquid crystal is particularly preferable in that a display element capable of performing bright display without a polarizing plate can be manufactured. Various materials such as a ferroelectric liquid crystal can be used.

[Brief description of the drawings]

FIG. 1 is an exemplary front view showing an electronic book device according to a first embodiment of the invention;

FIG. 2 is an exemplary perspective view showing a state in which the electronic book device is bent.

FIG. 3 is a cross-sectional view showing a bent portion of the electronic book device.

FIG. 4 is a cross-sectional view showing a first modification of the electronic book device.

FIG. 5 is a cross-sectional view showing Modification Example 2 of the electronic book device.

FIG. 6 is a cross-sectional view showing a modification 3 of the electronic book device.

FIG. 7 is an exemplary plan view showing a drive circuit of an electronic book device according to a second embodiment of the invention.

8 is a cross-sectional view of the electronic book device shown in FIG.

9 is a cross-sectional view of Modification Example 1 of the electronic book device shown in FIG.

FIG. 10 is a sectional view of a modification 2 of the electronic book device shown in FIG. 7;

FIG. 11 is an exemplary sectional view showing an electronic book device according to a third embodiment of the invention;

FIG. 12 is an exemplary sectional view showing an electronic book device according to a fourth embodiment of the invention;

FIG. 13 is an exemplary perspective view showing an electronic book device according to a fifth embodiment of the invention.

14 is a cross-sectional view of the electronic book device shown in FIG.

FIG. 15 is an exemplary perspective view showing an electronic book device according to a sixth embodiment of the invention;

16 is a cross-sectional view of the electronic book device shown in FIG.

FIG. 17: Electronic book bending system (first example)
FIG.

FIG. 18: Electronic book bending system (second example)
FIG.

[Explanation of symbols]

 1, 2, 3, 4, 5, 6 e-book readers 21, 22, 23, 24 liquid crystal display elements 25, 26, 27 support substrates 31, 32, 33, 34, 35, 36, 37 connecting members 41, 42: sheet material 43: liquid crystal 45: scanning electrode 55: flexible substrate A: bent portion

Continued on front page F-term (reference) 2H088 EA03 HA01 HA02 JA15 JA16 MA20 2H089 HA31 HA33 HA40 JA10 QA02 QA11 RA12 TA01 TA02 TA12 2H092 GA05 GA24 GA40 GA50 NA25 PA01 PA08 QA12 5C094 AA15 AA36 AA56 BA09 DA01 DA01 DA06 HA10

Claims (6)

[Claims] 1. A liquid crystal display device wherein a display element comprising a liquid crystal having a memory property sandwiched between a pair of sheet materials is planarly joined to a rigid support. 2. A plurality of display elements each comprising a liquid crystal having a memory property sandwiched between a pair of sheet materials are each planarly joined to a rigid support, and the support has flexibility. A liquid crystal display device, wherein the liquid crystal display device is foldably connected by an elastic member. 3. The liquid crystal display device according to claim 2, wherein a scanning electrode for driving the liquid crystal is wired across a plurality of display elements via the bent portion. 4. The liquid crystal display device according to claim 2, wherein the scanning electrodes provided on each display element are connected by a flexible substrate at the bent portion. 5. The method according to claim 1, wherein the bent portion has a spine portion that partially maintains a flat state when bent, and a display element including a liquid crystal having a memory function is provided on the spine portion. The liquid crystal display device according to claim 2. 6. The liquid crystal according to claim 1, wherein the liquid crystal is a chiral nematic liquid crystal.
A liquid crystal display device according to claim 4.