JP2001100916A - Liquid crystal touch panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a liquid crystal touch panel which has a display function and a position information input function combined together compactly. SOLUTION: The liquid crystal touch panel 10 is equipped with a liquid crystal display layer 20 which has a liquid crystal composition 26, which shows a cholesteric phase and holds a display while applied with no electric field, sandwiched between substrates 21 and 22 provided with electrodes 23 and 24. The display layer 20 is composed of many pixels which are arranged in matrix and a desired image is displayed by the matrix driving of the electrodes 23 and 24. When the substrate 21 is pressed with a finger, etc., the pressed pixels vary in electric capacity, which is detected through the electrodes 23 and 24 to detect the depression position.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal touch panel, and more particularly to a liquid crystal touch panel capable of displaying information on a liquid crystal and detecting a pressed position on a display screen.

[0002]

2. Description of the Related Art In recent years, various information display devices using a liquid crystal as a display medium have been provided. The biggest advantage of this type of information display device is that it is compact.
In order to further exhibit this advantage, it is preferable to incorporate an input function into the display element.

[0003] Therefore, on page 38 and page 39 (1985) of the eleventh meeting of the Liquid Crystal Study Group, the change in the distance between the electrodes of the panel when the display screen of the liquid crystal panel is pressed is described as the change in the capacitance. Thus, there is disclosed a liquid crystal panel having an input function of detecting a pressed position of the liquid crystal panel.

Japanese Patent Application Laid-Open No. 9-138385 discloses a liquid crystal panel in which a ferroelectric liquid crystal is sandwiched between substrates provided with electrodes, and a pressing position is generated by an electromotive force generated when the panel is pressed. Is disclosed.

By the way, liquid crystals which exhibit a cholesteric phase at room temperature, for example, cholesteric liquid crystals and chiral nematic liquid crystals are known. This type of liquid crystal has the memory property of maintaining the display even when no electric field is applied, and has the advantage that the display device can be made lighter, thinner, and energy-saving, and can be mounted on portable information display devices. Are suitable.

Accordingly, an object of the present invention is to use a liquid crystal composition exhibiting a cholesteric phase at room temperature, thereby enabling not only display of information but also detection of a pressed position on a screen.
An object of the present invention is to provide a liquid crystal touch panel in which a display function and a position information input function are compactly combined.

[0007]

In order to achieve the above objects, the liquid crystal touch panel according to the present invention comprises a liquid crystal composition exhibiting a cholesteric phase at room temperature sandwiched between a pair of substrates with electrodes, and applies an electric field. A liquid crystal display layer that maintains display in a state where the substrate is not pressed, and a pressing position detecting unit that detects a pressing position by electrically detecting a change in capacitance due to pressing of the substrate through the pair of electrodes. I have.

The liquid crystal composition exhibiting a cholesteric phase sandwiched between substrates is driven, for example, by being divided into a large number of pixels in a matrix. This liquid crystal composition has an electric capacity according to the thickness of the liquid crystal layer, and the capacity changes when the substrate is pressed. In the present invention, the pressed position is detected by electrically detecting a change in capacitance in each pixel via an electrode.

That is, according to the present invention, a compact liquid crystal touch panel capable of displaying visual information and inputting positional information can be provided. Since the content written with the touch or the input pen is displayed naturally, the written content is displayed without driving for display, and there is no time lag between the writing by the touch or the input pen and the display. . Moreover, the liquid crystal composition exhibiting a cholesteric phase maintains the display even after the application of the voltage is stopped.
The position information can be input while keeping the information display state on the screen.

Further, in the liquid crystal touch panel according to the present invention, the pressed position detecting means electrically detects a change in the alignment state of the liquid crystal due to the pressing of the substrate through the pair of electrodes, thereby detecting the pressed position. It may be one that detects.

A liquid crystal composition exhibiting a cholesteric phase switches the arrangement between a planar state and a focal conic state according to the magnitude of the energy of the applied voltage, and performs display. When the liquid crystal screen is set in any of the alignment states, the alignment changes by pressing, and the capacitance and the potential change. The pressed position is detected by electrically detecting this change.

A resin structure may be arranged in a predetermined arrangement together with a liquid crystal composition between a pair of substrates. By arranging the resin structure, the pressure resistance of the liquid crystal touch panel can be improved, and breakage or the like due to pressing can be prevented.

Further, at least the substrate to be pressed of the pair of substrates may have flexibility. By doing so, the pressure from the operator can be transmitted to the liquid crystal layer in a favorable manner. In particular, when resin structures are arranged in a predetermined arrangement between substrates, it is preferable because both pressurization and pressure resistance can be achieved.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the liquid crystal touch panel according to the present invention will be described with reference to the accompanying drawings.

(First Embodiment) FIG. 1 shows a sectional structure of a liquid crystal touch panel 10 according to a first embodiment of the present invention. This liquid crystal touch panel 10 has a light absorbing layer 1 on a support plate 11.
In this example, the liquid crystal display layer 20 is laminated via the second liquid crystal display layer 2.

(Structure and Operation of Liquid Crystal Display Layer) The liquid crystal display layer 20 includes a transparent substrate 21 on which transparent electrodes 23 and 24 are formed.
A resin-made columnar structure 25, a liquid crystal composition 26, and a spacer 27 are sandwiched between 22. Transparent electrodes 23, 24
On top, an insulating film 28 and an orientation control film 29 are provided as necessary. In addition, the outer peripheral portions of the substrates 21 and 22 (outside the display area)
Is provided with a sealant 30 for sealing the liquid crystal composition 26.

More specifically, in the liquid crystal display layer 20 in which a liquid crystal composition exhibiting a cholesteric phase is sandwiched between two substrates, display is performed by switching the liquid crystal state between a planar state and a focal conic state. When the liquid crystal is in a planar state and the helical pitch of the liquid crystal is P and the average refractive index is n, the wavelength λ =
P · n light is selectively reflected. In the focal conic state, the liquid crystal is scattered when the selective reflection wavelength of the liquid crystal is in the infrared light range, and transmits visible light when the selective reflection wavelength is shorter than that. Therefore, by setting the selective reflection wavelength in the visible light region and providing a light absorbing layer on the side opposite to the observation side of the element (the side indicated by arrow A), the display of the selective reflection color in the planar state and the black in the focal conic state are performed. Can be displayed. Also,
By setting the selective reflection wavelength in the infrared light range and providing a light absorbing layer on the side opposite to the observation side of the element, light in the infrared light range is reflected in the planar state, but light in the visible light range is reflected. Is transmitted, so that black display and white display due to scattering in the focal conic state are possible.

(Various Materials of Liquid Crystal Display Layer)
As 22, a colorless and transparent glass plate or a transparent resin film can be used. Examples of the material of the transparent resin film include a polycarbonate resin, a polyether sulfone resin, a polyethylene terephthalate resin, a norbornene resin, a polyarylate resin, an amorphous polyolefin resin, and a modified acrylate resin. The characteristics of resin film are high translucency, no optical anisotropy, dimensional stability, surface smoothness, friction resistance, bending resistance, high electrical insulation, chemical resistance, liquid crystal resistance, heat resistance What is necessary is to select a material having necessary properties in accordance with the environment and application in which the material has moisture resistance, gas barrier properties and the like.

As the transparent electrodes 23 and 24, ITO (In
A transparent electrode such as dium tin oxide can be used, and a metal electrode such as aluminum or silicon or a photoconductive film such as amorphous silicon or BSO (Bismuth Silicon Oxide) can also be used. For the lower transparent electrode 24, a black electrode can be used including the role as a light absorber.

As the insulating film 28, an inorganic film such as silicon oxide or an organic film such as polyimide resin or epoxy resin is used so as to function also as a gas barrier layer.
It prevents short circuit between 3, 24 and improves the reliability of liquid crystal. The alignment control film 29 is typically made of polyimide.

The liquid crystal composition 26 preferably exhibits a cholesteric phase at room temperature. In particular, a chiral nematic liquid crystal obtained by adding a chiral material to a nematic liquid crystal is suitable.

The chiral material is an additive having a function of twisting the molecules of the nematic liquid crystal when added to the nematic liquid crystal. By adding a chiral material to a nematic liquid crystal, a helical structure of liquid crystal molecules having a predetermined twist interval is generated, thereby exhibiting a cholesteric phase.

The chiral nematic liquid crystal has an advantage that the pitch of the helical structure can be changed by changing the amount of the chiral material to be added, whereby the selective reflection wavelength of the liquid crystal can be controlled. Note that, as a general term indicating the pitch of the helical structure of the liquid crystal molecules, “helical pitch” defined by the distance between the liquid crystal molecules when the liquid crystal molecules rotate 360 degrees along the helical structure of the liquid crystal molecules is used. .

Materials used for the columnar structure 25 include:
For example, a thermoplastic resin can be used. For this purpose, a material which is softened by heating and solidified by cooling, is desired not to cause a chemical reaction with a liquid crystal material to be used and to have appropriate elasticity.

As specific examples, for example, polyvinyl chloride resin, polyvinylidene chloride resin, polymethacrylate resin, polyacrylate resin, polyvinyl acetate resin, polystyrene resin, polyamide resin, polyethylene resin, polypropylene resin, fluorine resin Resins, polyurethane resins, polyacrylonitrile resins, polyvinyl ether resins, polyvinyl ketone resins, polyvinyl pyrrolidone resins, polycarbonate resins, chlorinated polyether resins, saturated polyester resins, and the like.

The columnar structure 25 may be formed from a material containing at least one of them or a mixture thereof, or a material containing at least one or a mixture thereof.

The substance is printed by a known printing method using a pattern so as to form dot columns as shown in FIG. Depending on the size of the liquid crystal display layer 20 and the pixel resolution, the size of the cross-sectional shape, the arrangement pitch, and the shape (such as a cylinder, a drum, and a polygon) are appropriately selected. It is more preferable that the columnar structure 25 is preferentially arranged between the electrodes 23 because the aperture ratio is improved.

As the spacer 27, particles made of a hard material which is not deformed by heating or pressing are preferable. For example, finely divided glass fibers, inorganic materials such as ball-shaped silicate glass and alumina powder, or organic synthetic spherical particles such as divinylbenzene-based crosslinked polymers and polystyrene-based crosslinked polymers can be used.

As described above, by providing the columnar structure 25 mainly composed of a thermoplastic polymer material for bonding and supporting the pair of substrates 21 and 22, they are firmly supported over the entire area of the substrates 21 and 22. To maintain the gap at a predetermined size, eliminate unevenness in the concentration of the liquid crystal composition 26, and
The generation of air bubbles can be suppressed in a low-temperature environment.
Further, the arrangement of the spacers 27 also greatly contributes to maintaining the gap between the substrates.

(Example of Manufacturing Liquid Crystal Display Layer) Here, an example of manufacturing the liquid crystal display layer 20 will be briefly described. First, a plurality of strip-shaped transparent electrodes are formed on two transparent substrates, respectively. The transparent electrode is formed by forming an ITO film on a substrate by a sputtering method or the like and then performing patterning by a photolithography method.

Next, a transparent insulating film and an orientation control film are formed on the transparent electrode forming surface of each substrate. The insulating film and the orientation control film can be formed by a known method such as a sputtering method, a spin coating method, or a roll coating method using an inorganic material such as silicon oxide or an organic material such as a polyimide resin.

The rubbing treatment is not usually applied to the orientation control film. Although the function of the alignment control film is not yet clear, it is thought that the presence of the alignment control film can have a certain degree of anchoring effect on liquid crystal molecules.
It is possible to prevent the characteristics of the liquid crystal display element from changing over time. In addition, a function as a color filter may be provided by adding a dye to these thin films to improve color purity and contrast.

Thus, a columnar structure is formed on the electrode forming surface of one of the substrates provided with the transparent electrode, the insulating film, and the alignment control film. The columnar structure is a printing method in which a paste-like resin material obtained by dissolving a resin in a solvent is extruded with a squeegee through a screen plate or a metal mask and printed on a substrate mounted on a flat plate, a dispenser method or an inkjet method. For example, it can be formed by a method in which a resin material is discharged onto a substrate from the tip of a nozzle, or a transfer method in which a resin material is supplied onto a flat plate or a roller and then transferred to the substrate surface. . It is desirable that the height at the time of forming the columnar structure be larger than the desired thickness of the liquid crystal display layer.

A sealing material is provided on the electrode forming surface of the other substrate by using an ultraviolet curable resin, a thermosetting resin, or the like. The sealant is arranged in a continuous ring at the outer edge of the substrate. As in the case of the columnar structure, a method of forming a resin by discharging a resin from the tip of a nozzle onto a substrate, a screen plate, a printing method using a metal mask or the like, a resin, Is formed on a flat plate or a roller and then transferred onto a transparent substrate by a transfer method or the like. Further, spacers are sprayed on the surface of at least one of the substrates by a conventionally known method.

Then, the pair of substrates are overlapped so that the electrode forming surfaces face each other, and heated while applying pressure from both sides of the pair of substrates. Pressing and heating are performed, for example, as shown in FIG. 3, by placing the substrate 21 on which the columnar structure 25 is formed on the flat plate 50, stacking the counter substrate 22, and heating and heating from the end.
The roller 51 is heated and pressed by the pressing roller 51.
And the flat plate 50. When such a method is used, a display layer can be accurately manufactured even when a flexible substrate having flexibility such as a film substrate is used. If the columnar structure is formed of a thermoplastic polymer material, the columnar structure can be softened by heating and solidified by cooling, and the two substrates can be bonded by the resin structure. When a thermosetting resin material is used as the sealing material, the sealing material may be cured by heating when the substrates are superposed.

In this superposition step, the liquid crystal composition is dropped on one of the substrates, and the liquid crystal composition is injected between the substrates simultaneously with the superposition of the substrates. In this case, the spacer may be included in the liquid crystal composition in advance, and the spacer may be dropped on at least one of the substrates on the surface where the band-shaped electrode is formed.

The liquid crystal composition can be filled in the entire area of the substrate by dropping the liquid crystal composition on the edge of the substrate and spreading the liquid crystal composition to the other end while overlapping the substrates with a roller. By doing so, it is possible to reduce the entrapment of bubbles generated when the substrates are overlapped with each other in the liquid crystal material.

Thereafter, the substrate is continuously pressed until the substrate temperature falls below the softening temperature of the resin material constituting at least the columnar structure, and then the pressing is stopped, and a photocurable resin material is used as a sealing material. If so, light irradiation is performed thereafter to cure the sealing material.

(Control Circuit) Next, the control circuit 60 of the liquid crystal touch panel 10 will be described with reference to FIG. The control circuit 60 is mainly configured by a central processing unit 61, and includes a ROM 62 storing various control programs, a RAM 63 temporarily storing various information, and a power supply 64.
The central processing unit 61 exchanges signals with the external device (personal computer body) 1.

The image information input from the external device 1 to the central processing unit 61 is transferred to the image processing unit 65, where the image data to be written in the liquid crystal display layer 20 is created and output to the image memory 66. In response to a command from the central processing unit 61, the LCD controller 67 causes the image memory 6
An image is written on the liquid crystal display layer 20 based on the image data stored in the LCD 6. When changing the display items and the display layout of the liquid crystal display layer 20, the image processing device 65 receives image data from the external device 1, performs necessary image processing, and outputs the processed image data to the image memory 66.

The pixel configuration of the liquid crystal display layer 20 includes a plurality of scanning electrodes R1, R2 to Rm and signal electrodes C1, C2.
To Cn (n and m are natural numbers).
The scan electrodes R1, R2 to Rm are connected to a scan drive IC 71, and the signal electrodes C1, C2 to Cn are connected to a signal drive IC 72.

Each of the driving ICs 71 and 72 is connected to the LCD controller 67,
Is a driving IC based on the information stored in the image memory 66.
By controlling 71 and 72, a voltage is sequentially applied between each scanning electrode and signal electrode of the liquid crystal display layer 20, and an image is written on the liquid crystal display layer 20.

The scanning drive IC 71 includes scanning electrodes R1 and R2.
... Rm to a selected state by outputting a selection signal, while outputting a non-selection signal to the other electrodes in a non-selected state. The scan driving IC 71 sequentially switches the scan electrodes R1 and R2 while switching the electrodes at predetermined time intervals.
To Rm. On the other hand, signal drive IC
Reference numeral 72 simultaneously outputs a signal corresponding to image data to each of the signal electrodes C1, C2 to Cn in order to rewrite each pixel on the selected scanning electrode R1, R2 to Rm. For example,
When the scanning electrode Ra is selected (a is a natural number satisfying a ≦ m), the scanning electrode Ra and each of the signal electrodes C1, C2 to Cn
, The pixels LRa-C1 to LRa-Cn at the intersection with are rewritten simultaneously. Thereby, the voltage difference between the scanning electrode and the signal electrode in each pixel becomes the rewriting voltage of the pixel,
Each pixel is rewritten according to the rewriting voltage.

Here, assuming that the first threshold voltage for untwisting the liquid crystal exhibiting the cholesteric phase is Vth1, after applying the voltage Vth1 for a sufficient time, the second threshold voltage lower than the first threshold voltage Vth1 is applied. When the voltage drops below the threshold voltage Vth2, a planar state is set. When a voltage of Vth2 or more and Vth1 or less is applied for a sufficient time, a focal conic state is established. These two states are stably maintained even after the voltage application is stopped. By applying a voltage between Vth1 and Vth2, halftone display, that is, gradation display is possible.

Rewriting of each pixel can be performed by the method described above. However, when an image is already displayed, all the pixels must be reset to the same display state before rewriting in order to eliminate the influence of the image. Is preferred. The reset may be performed for all pixels at once or for each scan electrode. For example, it has been found that when resetting each pixel to the focal conic state, a relatively long time is required to obtain a sufficient transparent state. Therefore, it is preferable to collectively reset all the pixels to the focal conic state before rewriting because the rewriting time can be shortened as compared with the case where resetting is performed for each scanning electrode.

(Detection of Pressing Position) The liquid crystal composition 26 has an electric capacity corresponding to the thickness of the liquid crystal layer, and when the substrate 21 is pressed with a finger or a pen,
Its capacity changes. FIG. 5 shows an equivalent circuit in which the liquid crystal composition has a capacitance for each pixel.
The charge position detector 68 is provided in each of the pixels 1 and 72, and the pressed position is detected by detecting a change in capacitance at each pixel.

In the first embodiment, the pressed position is detected by the processing described below. The first stage detects and stores the capacitance for every pixel and the capacitance for each scan line. The measurement of the capacity is performed as follows.

Measurement of Capacitance on Scan Electrode Ri (1 ≦ i ≦ m) First, from the state where the outputs of the scan drive IC 71 and the signal drive IC 72 are all set to 0 V, only the output of a specific scan electrode Ri of the scan drive IC 71 To Vs. However, Vs is a low voltage that does not change the orientation of the liquid crystal. At this time, assuming that the amount of charge flowing through the charge amount detector 68 is Q1 coulomb, the capacitance CRi on the scan electrode Ri is CRi = Q1
/ Vs. This is repeated from i = 1 to m,
The capacitance on each scanning electrode is determined.

Measurement of Pixel Capacitance In order to detect the capacitance selected by the scanning electrode Ri and the signal electrode Cj (1 ≦ j ≦ n), only the output of the specific signal electrode Cj is set to Vs from the above state. Then, the terminal on the low voltage side of the capacitor Cij charged to Vs becomes Vs, so that the charge charged by the voltage Vs becomes the scan driving I.
It is returned to the power supply side of C71. This charge amount is detected by the charge amount detector 68. Assuming that the detected charge amount is Qij coulomb, the capacitance Cij is obtained by Cij = Qij / Vs. This is repeated from j = 1 to n to determine the capacitance of the pixel on each signal electrode for a specific scanning electrode.

In the second stage, the capacitance is detected for each scanning line by performing the above-described measurement for each scanning line. Then, the detected capacity is compared with the capacity of the corresponding scanning line stored in the first stage. If there is a line having a different capacity, it is the position where any pixel of the line is pressed.

The third step is performed subsequent to the second step. One of the switches corresponding to the scanning line in which the change in capacitance is detected is turned on, and the switch for the signal electrode is turned on one by one. . Thus, the capacitance of each pixel is detected in one scanning line, and the detection result is compared with the capacitance of the corresponding pixel stored in the first stage. Pixels having different capacitances are the pressed positions.

The liquid crystal enters a planar state by writing with a touch or an input pen or the like. If the focal conic state has been reset in advance, or if the display is being performed in the cholesteric state with the focal conic state as the background, the pressed part will be in the planar state, and the written contents will be displayed naturally. Will be. That is, the written contents are displayed without driving for display, and there is no time lag between writing and display with a touch or an input pen or the like.

(Control Procedure) Here, the control procedure for detecting the pressed position in the first embodiment will be described with reference to FIG. In the first embodiment, the pressed position can be detected in real time while an image is displayed on the liquid crystal touch panel 10.

The processing for detecting the pressed position shown in FIG. 6 is inserted as a subroutine for the control of the central processing unit 61. When the detection of the pressed position is instructed, first,
In step S100, the first-stage processing described above is executed, and the capacitance of each pixel and each scanning line of the liquid crystal touch panel 10 is detected / stored. In this case, some image may be displayed on the liquid crystal display layer 20.

Here, if the rewriting of the screen is instructed (YES in step S102), a scan for rewriting the screen is executed in step S104, and the capacity of each pixel and each scanning line is determined for the rewritten screen in step S106. Detect / store. Next, pressing position detection scanning is performed in step S108, and pressing position calculation is performed in step S110. In these steps S108 and S110, the processes in the second and third stages described above are executed, and the pressed position is specified.

Next, after confirming that the pressing has been performed in step S112, the pressing position information is transmitted to the external device in step S114. Then, when it is confirmed in step S116 that the detection end has been instructed, the subroutine ends. Step S1 is performed while the detection end is not instructed.
02 and the above-described processing is repeated. In this way, the pressing position detection scanning is repeated in a short time, and the pressing position is detected in real time.

The capacity measurement at the first stage is not always necessary, and the capacity of each pixel can be estimated based on the displayed data. Therefore, the capacity estimated based on the displayed data is stored. You may do it.

(Second Embodiment) In the second embodiment, a change in the alignment state of the liquid crystal caused by pressing the substrate of the liquid crystal display layer is electrically detected through a pair of electrodes. The configuration of the liquid crystal touch panel is the same as that of the first embodiment shown in FIGS. 1, 4, and 5.

In the pressed position detection mode in the second embodiment, the liquid crystal is set to one of the planar state and the focal conic state as a first step. The capacity of each pixel and each scanning line in this state is known in advance and stored in the ROM 62. Next, the processing in the second and third stages described in the first embodiment is executed to specify the pressed pixel. At this time, the change in the alignment state can be regarded as a difference in the degree between the planar state and the focal conic state. Therefore,
It is appropriate that the ROM 62 has a storage capacity of a plurality of bits.

Here, a control procedure for detecting a pressed position in the second embodiment will be described with reference to FIG.

When the pressed position detection is instructed, it is first determined in step S300 whether or not the pressed position detection mode has been set.
In step 314, the liquid crystal is set to one of the planar state and the focal conic state.
To set the pressed position detection mode.

Next, a pressing position detection scan is performed in step S302, and a pressing position calculation is performed in step S304. In steps S302 and S304, step S1 is performed.
Similarly to the steps 08 and S110, the processing of the second and third steps described above is executed, and the pressed pixel is specified by comparison with the capacity stored in advance. Next, the pressed position information is transmitted to the external device in step S306, and when it is confirmed in step S308 that the detection end has been instructed, the subroutine ends.

(Other Embodiments) The liquid crystal touch panel according to the present invention is not limited to the above-described embodiment.
Various changes can be made within the scope of the gist.

For example, the liquid crystal touch panel may be mounted on a portable electronic book device, or may be used as a sub-display of a terminal device having a commonly used TFT liquid crystal display. Further, it can be used for a bulletin board, an advertising board, and the like.

In particular, the liquid crystal touch panel 10 shown in FIG.
Since is a sheet shape, it can be used by applying an adhesive to the back surface of the support plate 11 and attaching it to another device.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a liquid crystal touch panel according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of a manufacturing process of a liquid crystal display layer constituting the liquid crystal touch panel.

FIG. 3 is an explanatory view of a manufacturing process of the liquid crystal display layer.

FIG. 4 is a block diagram showing a control circuit of the liquid crystal touch panel.

FIG. 5 is a block diagram showing an equivalent circuit of each pixel of the liquid crystal display layer.

FIG. 6 is a flowchart showing a processing procedure of a pressed position detection control in the first embodiment.

FIG. 7 is a flowchart illustrating a processing procedure of pressing position detection control according to the second embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Liquid crystal touch panel 20 ... Liquid crystal display layers 21, 22 ... Substrates 23, 24 ... Electrodes 61 ... Central processing unit (CPU) 68 ... Charge amount detector

 ──────────────────────────────────────────────────続 き Continued on front page F-term (reference) 2H089 HA18 LA07 LA09 NA13 NA24 NA42 NA44 NA48 NA58 RA11 TA01 TA05 TA07 5B087 AA06 AE09 CC02 CC14 CC16 CC31 5C094 AA15 AA22 AA36 AA45 BA09 BA14 BA43 BA49 CA19 DA12 DA13 DB01 DB02 DB04 EA04 EB02 EC03 ED14 FA01 FA02 FB01 FB15 GB10 HA10 5G435 AA09 AA16 AA18 BB12 BB16 CC09 DD17 EE10 FF05 FF14 GG43 HH12 HH18 KK05 LL00

Claims (4)

[Claims] 1. A liquid crystal display layer in which a liquid crystal composition exhibiting a cholesteric phase at room temperature is sandwiched between a pair of substrates with electrodes to maintain a display without applying an electric field, and a capacitance caused by pressing the substrate. A liquid crystal touch panel, comprising: a pressing position detecting unit that detects a pressing position by electrically detecting a change through the pair of electrodes. 2. A liquid crystal display layer in which a liquid crystal composition exhibiting a cholesteric phase at room temperature is sandwiched between a pair of substrates with electrodes to maintain a display without applying an electric field, and a liquid crystal formed by pressing the substrate. And a pressing position detecting means for detecting a pressing position by electrically detecting a change in the alignment state of the liquid crystal panel via the pair of electrodes. 3. The liquid crystal touch panel according to claim 1, wherein a resin structure is arranged in a predetermined arrangement together with the liquid crystal composition between the pair of substrates. 4. The liquid crystal touch panel according to claim 1, wherein at least the substrate on the pressed side of the pair of substrates has flexibility.