JP3466081B2 - Liquid crystal display device and position detection device - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device having a display screen having a position detecting function, and more particularly to a liquid crystal display device having a display screen having a position detecting function. The present invention also relates to a position detecting device, and more particularly to a position detecting device having high compatibility with a display device.

[0002]

2. Description of the Related Art In recent years, liquid crystal display devices have been improved in image quality and definition, and are becoming the mainstream in place of cathode ray tubes as small and medium-sized displays such as displays for personal computers. Further, due to recent advances in mobile communication technology, the development of liquid crystal display devices as mobile terminals is expected.

It is desirable that the portable terminal has a function of detecting the coordinates of the pressure point from the writing input pen or the finger. Currently, a transparent resistance film is used as an input method like this.
A resistance film resistive film pressure sensitive method utilizing the fact that the resistance films are short-circuited by applying pressure is the mainstream, and this position detection device is externally used on the observation side in a liquid crystal display device.

The external method of such a position detecting device has the following problems. First, (1)
There is a problem that display quality is deteriorated due to light loss due to reflection / absorption by an external position detection device, and (2) a display image becomes a double image due to reflection by an external position detection device. Reflection at the transparent electrode / air interface in the resistance film pressure sensitive system is about 5% per interface,
The absorption on the substrate and the transparent electrode is about 5 [%]. Therefore, the light loss is (1-0.9) in the transmissive liquid crystal display device.
² =) 20 [%] or so, the optical path is doubled in the reflective type liquid crystal display device (1-0.9 ⁴ =) is 35 [%] degree. It is possible to compensate for such light loss by the brightness of the backlight, but in that case the power consumption increases.
In the reflective liquid crystal display, the image quality is deteriorated due to insufficient reflectance due to a position detection device externally attached on the display screen. Particularly in the case of a reflective liquid crystal display device, since the display brightness is originally limited, the deterioration of the image quality due to the light loss becomes a serious problem.

When a position detecting device is externally attached,
(3) It is difficult to obtain sufficient bonding accuracy between the position detection device and the display device, and there is a problem that the input position and the display coordinates of the liquid crystal display device are displaced. The external method requires a step of attaching a position detection device that performs coordinate input and the like to the display device, but it is difficult to attach both devices with high accuracy, and this causes a difference between the display position and the coordinate input position. Becomes In order to solve this positional deviation, it is necessary to make a circuit correction for each product, which causes an increase in cost.

(4) There is also a problem of parallax displacement between the input position and the display position, which is caused by the thickness of the position detecting device.

If the display screen of the display device and the position detecting device are attached to each other in contact with each other, interference fringes due to unevenness in the gap are generated, and the display quality is significantly deteriorated. Therefore, it is necessary to provide a gap of about 1 [mm] between the display screen of the display device and the position detection device. As a result, there is a distance between the coordinate detection surface of the position detection device and the display screen of the display device, which is equal to the thickness of the position detection device plus the thickness of the gap. There is a problem that the display position and the coordinate input position may deviate from each other (parallax) depending on the direction of the line of sight.

Further, (5) there is a problem that the thickness and weight of the entire display device are increased due to the external position detection device. The external resistance film pressure-sensitive method has a problem that it is difficult to reduce the weight and thickness of the module because the thickness of the above-mentioned gap is added to the weight and thickness of the external member. Particularly in the case of a portable electronic device, an increase in weight and size reduces portability.

[0009]

The present invention has been made to solve the above problems. That is, the present invention solves the above-mentioned problems in the conventional display device with an external position detection function, and provides a display device with high display quality without deterioration in image quality due to the addition of the position detection function. To aim. It is another object of the present invention to provide a display device having a position detection function with high input position accuracy, which is free from misalignment and parallax. It is another object of the present invention to provide a display device which is light and thin and is suitable for mobile use, in which the weight and size are not increased by adding a position detecting function.

Another object of the present invention is to provide a display device with a position detecting function which consumes less power. Another object of the present invention is to provide a display device with a position detection function, which has a structure with high productivity.

[0011]

Any of the above problems can be solved by incorporating a coordinate input function in the display device itself such as a liquid crystal cell. However, since the liquid crystal display device is in a display state due to the potential difference between the electrodes at both ends of the cell gap, the conventional resistance film pressure (contact) method cannot be simply built in the liquid crystal cell. The present invention has a coordinate input function incorporated in the display device by adopting the configuration described below.

In order to solve the above problems, the present invention has the following configuration. A liquid crystal display device of the present invention includes a first substrate on which a first electrode is provided, a second substrate on which a second electrode is provided, the first substrate and the second substrate. Columnar spacers arranged in a matrix between, and a liquid crystal layer sandwiched in the gap between the first substrate and the second substrate held by the spacer,
Means for applying a display signal voltage to the first electrode or the second electrode, and a means for applying a display signal voltage to the first substrate and the spacer.
Or between the second substrate and disposed pressure sensing element between the spacers, when the pressure is applied to the pressure sensing element, on the basis of an output signal of the pressure sensing element, wherein the pressure is applied characterized by comprising a means to detect the position of the pressure detection element.

Further, a first substrate on which the first electrode is arranged, a second substrate on which the second electrode is arranged, and between the first substrate and the second substrate Display signals are provided between the spacers arranged in a matrix, the liquid crystal layer sandwiched between the first substrate and the second substrate, and the first electrode and the second electrode. Means for applying a corresponding voltage,
Between the first substrate and the spacer, or the second
A pressure detecting element disposed between the substrate and the spacer , and when pressure is applied to the pressure detecting element, the pressure detecting element to which the pressure is applied based on resistance change or induced potential of the pressure detecting element. it may be and a means to detect the position.

Further, it has a first region and a second region,
A first substrate having a first electrode arranged in the first region, a first region and a second region, and a second electrode arranged in the first region. Between the second substrate and the first substrate and the second substrate so as to face the second region of the first substrate and the second region of the second substrate. Columnar spacers arranged in a matrix, a liquid crystal layer sandwiched between the first substrate and the second substrate held by the spacers, and the first spacer
Means for applying a display signal voltage to the electrode or the second electrode, and a pressure detection element arranged in the second region of the first substrate or the second region of the second substrate. And a means for detecting the position of the pressure detecting element to which the pressure is applied, based on the output signal of the pressure detecting element, when the pressure is applied to the pressure detecting element.

It is known that when a pressure is applied to a part of the display area of the liquid crystal display device, most of the pressure is supported by the spacers arranged in the area. The present invention utilizes this pressure concentration on the spacer portion to detect the position coordinates by the pressure detection element provided on the spacer portion.

The present invention may be applied to an active matrix type liquid crystal display device or may be applied to a simple matrix type liquid crystal display device.

Further, in the case of the active matrix type liquid crystal display device, a scanning signal is applied from the scanning line drive circuit to the scanning line and a display signal is applied from the signal line drive circuit to the signal line. Then, the non-linear switching element such as a thin film transistor or MIM provided for each pixel electrode is turned on and off according to the scanning signal, and the display signal applied to the signal line when in the on state is selected and applied to the pixel electrode. .

Further, by adjusting the height of the columnar spacers, the thickness of the liquid crystal layer (cell gap) and the density of the spacers can be adjusted to optimize the pressure range applied to each spacer. It will be possible. Other than the columnar spacer, for example, a spherical spacer may be used as long as the spacer can be arranged at an appropriate position so as not to overlap with the pixel and correspond to the pressure detection element. At least a part of the spacer may be made of a piezoelectric material.

A resistance film may be further provided so as to be in contact with the pressure detection element, and the output signal of the pressure detection element may be detected through the resistance film. In this case , the resistance film may be patterned so as not to overlap the pixel region of the liquid crystal display element.
It may also be shared with a light-shielding film called a so-called black matrix. By adopting such a configuration, it is possible to avoid the optical loss due to the absorption of the resistance film and the influence of the potential of the resistance film on the liquid crystal display. Further, by using a black matrix that originally exists in the liquid crystal display device as the resistance film, the number of steps can be reduced and productivity can be improved as compared with the case where the resistance film is separately formed.

By outputting the output signal from the pressure detecting element through the resistance film, it is output from the end portion of the substrate such as the outer peripheral portion of the pixel region by utilizing the distance dependency of the resistance or capacitance from the pressurizing portion. The position coordinates may be detected from the ratio of the signals.

The position detecting device of the present invention comprises a first substrate,
A second substrate, columnar spacers arranged in a matrix between the first substrate and the second substrate, and between the first substrate and the spacer, or the second substrate And a pressure detecting element arranged between the spacer and a pressure detecting element to which the pressure is applied, based on an output signal of the pressure detecting element when pressure is applied to the pressure detecting element. And a means for detecting the position.
By adopting such a configuration, the position detecting device of the present invention can improve the compatibility with the display device. For example, a liquid crystal composition is provided in a gap between a first substrate and a second substrate held by a spacer, and an electrode is provided on the first substrate or the second substrate to obtain an electro-optical response of the liquid crystal layer. Is controlled, it is possible to achieve both the position detection function and the display function without deteriorating the display quality and keeping the size of the display device compact. Further, for example, a field emission display may be configured by arranging field effect cold cathodes in an array in the gap between the first substrate and the second substrate held by the spacer.
Further, the present invention may be applied to a plasma addressed liquid crystal display device.

That is, the liquid crystal display device of the present invention is a liquid crystal display device in which the pressure detection element and the spacer are arranged so as to face each other.

A first substrate provided with a first electrode pattern, a second substrate provided with a second electrode pattern, and a substrate sandwiched between the first substrate and the second substrate. A liquid crystal layer, means for applying a display signal voltage to the first electrode or the second electrode, and maintaining the thickness of the liquid crystal layer between the first substrate and the second substrate. In a liquid crystal display device having spacers sandwiched between the first substrate and the second substrate or between the first substrate and the second substrate. And the pressure detecting element and the spacer are opposed to each other. Further, a part of the spacer is composed of a pressure detection element, by applying pressure from the observation side of the liquid crystal display device to a part of the display region of the liquid crystal display device,
Pressure is applied to the pressure detection element in the vicinity of the position where the pressure is applied in the display area, and means for detecting the position where the pressure is applied is detected based on the output signal from the pressure detection element. Further, a resistance film is provided on at least one of the first substrate and the second substrate, a part of the resistance film and the pressure detection element face each other, and the resistance film and the second film are provided. At least one of the first electrode and the second electrode is electrically insulated), and the output signal from the pressure detection element is output as an electric signal in the non-display area of the liquid crystal display device through the resistance film. It may be done.

As such a pressure detecting element, for example, a piezoelectric body that generates surface charge by pressure may be used, and the position may be detected by using current or charge amount as the electric signal. The piezoelectric body is one that generates surface charges when pressure is applied. Letting the force applied to the piezoelectric body be F for the piezoelectric constant (d ₃₃ ) and the generated electric charge (Q),
It has the following relationships. Q = d ₃₃ × F [C] Therefore, the position can be detected by utilizing this charge. For example, the charge may be detected by time integration of current. The area of the piezoelectric body is based on the above formula,
It may be adjusted so as to obtain an appropriate amount of charge.

Further, as the pressure detecting element, for example, a pressure sensitive body whose electric resistance changes with pressure may be used, and the position may be detected by using current or voltage as the electric signal. Here, the pressure sensitive element is an element whose resistance changes when pressure is applied. As the pressure sensitive body, for example, a material in which conductive fine particles are dispersed in an insulating material may be used. When the conductive fine particles come into contact with each other due to the pressure, the resistance greatly changes. That is, ideally, a pressure application causes a change from an insulating state to a conducting state. Therefore, the position detection may be performed by utilizing the resistance change (ON / OFF) caused by applying the pressure to the pressure sensitive body. Further, the area and thickness of the pressure sensitive body may be adjusted so that a pressure capable of obtaining an appropriate ON / OFF ratio is applied.

Further, the pressure detecting element may be composed of a transistor in which a piezoelectric body is electrically connected to the gate, and the position may be detected by using current or voltage as the electric signal. For example, by applying pressure to the piezoelectric body connected to the gate electrode of the TFT, the gate voltage is changed to turn ON / OFF the resistance between the source and drain.
The position may be detected by performing control. In order to secure an appropriate ON / OFF margin, the area / thickness of the piezoelectric body and the bias voltage applied to the piezoelectric gate may be adjusted.

Further, the first electrode (pixel electrode) is electrically coupled to the switching elements arranged in a matrix, and the second electrode is a common electrode for driving liquid crystal, A counter electrode for position detection, which is electrically coupled to the resistance film via a pressure detection element, is provided, and the common electrode for driving the liquid crystal and the counter electrode for position detection are electrically connected. May be. For example, by setting the common electrode, which originally exists in the liquid crystal display device, and the bias electrode of the surface-divided position detection element to the same potential, it is possible to reduce noise due to the coupling of the two. Further, the number of steps can be reduced and productivity can be improved as compared with the case where the bias electrode is formed separately.

Here, a method of designing the spacer in the liquid crystal display device and the position detection device of the present invention will be described.

When the liquid crystal cell is pressurized, most of the pressure is supported by the spacer. When a force of N [N / cm ² ] is applied to a cell having a spacer density of n [cells / cm ² ], the force applied per spacer is N / n [N / cell].

The columnar spacers can be formed by a series of photo-etching processes such as resist coating, exposure, development and baking. Further, the secondary shape / density / position of the spacer may be controlled by the mask pattern at the time of exposure. The pressure range applied to each spacer can be optimized depending on the arrangement density of the spacers.

When the disposing position of the spacer and the disposing position of the piezoelectric body are overlapped or the spacer itself is composed of the piezoelectric body, the charge amount (Q) generated at both ends of one spacer is calculated as follows. It Q = d ₃₃ × N ÷ n [C] When pressure is applied using a writing input pen or a finger, common sense pressure is N = 0.1 to 1 [kg / cm ² ] = 9.8.
˜98 [N / cm ² ]. This value, the piezoelectric constant (d ₃₃ ) of the piezoelectric material used, the method of detecting the output signal, and the S
The optimum spacer density may be set by setting / N or the like.

Even if there is a pressure sensitive body at the spacer position, or if the spacer itself is a pressure sensitive body, the optimum density of spacers should be set similarly from the pressure dependency of the resistance of the pressure sensitive body. .

Next, a method of designing the resistance film in the liquid crystal display device or the display device of the present invention will be described.

In the present invention, the piezoelectric body or the pressure sensitive body and the resistance film are arranged in contact with each other. FIG. 9 is a diagram for explaining the relationship between the liquid crystal cell and the resistance film. The resistance film 1 may be formed on one surface (FIG. 9A) of the liquid crystal cell 2 including the first substrate and the second substrate on which the piezoelectric body or the pressure sensitive body is arranged, or both surfaces ( It may be formed in FIG. 9 (b). When it is formed on one surface, it is effective to use the other as a bias applying electrode having sufficiently lower resistance than the resistance film 1 (FIG. 9A). When a solid resistance film is used, it is effective to provide a signal extraction electrode 3 having a resistance sufficiently lower than that of the resistance film in the peripheral portion and obtain an output signal from the signal extraction electrode 3 (FIGS. 9A and 9B). . In the case of the surface-divided type, the signal take-out electrode 3 is provided on four sides of the resistive film (FIG. 9A), and on each side of the two-sided resistive film (FIG. 9B).
Is effective. Further, the shape of the signal extraction electrode 3 may be modified for the purpose of reducing interference between the signal extraction electrodes 3.

Also, for example, when a resistance film patterned in a pattern complementary to the pixel region is used, the resistance film 2 may be formed on one surface (FIG. 11A) of the liquid crystal cell but on both surfaces (FIG. 11A). 11 (b)). When it is formed on one side, it is effective to use the other side as a bias applying electrode having sufficiently lower resistance than the resistance film (FIG. 11A). The bias application electrode may also be patterned. However, in this case,
It is necessary that an electrode for bias application remains on a portion of the piezoelectric body or pressure sensitive body. Also in the case where the resistance films are formed on both surfaces, it may be that both surfaces are patterned so as to be orthogonal to each other on the stripe (FIG. 11B), or only one surface is patterned and the remaining one surface is a solid film. . When both surfaces are patterned on the stripe so as to be orthogonal to each other, the piezoelectric body or the pressure sensitive body may be arranged at the intersection. When patterning the resistive film on the stripe, even if the output from the stripe electrode is used as it is as an output signal, a signal extraction electrode with a resistance sufficiently lower than that of the resistive film is provided in the periphery and the output signal is obtained from it. I don't mind. In order to reduce the cost of the output signal processing circuit, it is desirable to provide the signal extraction pole 3 in the peripheral portion and perform collective signal processing (FIG. 1).
1 (a), FIG. 11 (b)). In the case of the surface-divided type, the signal extraction electrodes 3 are arranged on four sides of the resistive film (FIG. 11A), and on each side of the double-sided divided resistive film (FIG. 11B). The resistance of the resistance film may be optimally designed according to the detection method / output range of the output signal, the S / N setting, and the like.

Further, by disposing the resistance film 2 only in the non-opening portion of the liquid crystal display device, it is possible to avoid light loss due to absorption of the resistance film and influence of the potential of the resistance film on the liquid crystal display. The quality can be improved.

FIG. 10 is a diagram schematically showing an example of the pattern of the resistance film. By forming the resistance film 3 as a black light-shielding film and forming the resistance film 3 as a black matrix of a liquid crystal display device, it is effective in reducing processes and reducing costs.

Further, the surface division type bias electrode is used for the TFT.
By setting the potential of the common electrode of the liquid crystal display device, it is effective in reducing the noise due to the coupling capacitance with the common electrode and reducing the bias electrode forming process to reduce the cost. Next, a coordinate calculation method in the liquid crystal display device with a position detection function of the present invention will be described.

FIG. 12 is a diagram for explaining an example of a coordinate calculating method in the case where the pressure detecting element is made of a piezoelectric material and the amount of electric charge is detected. When pressure is applied to the piezoelectric body, surface charge is induced at the position where the pressure is applied. This electric charge is attenuated with a time constant proportional to the product of the resistance R of the resistance film and the capacitance C, and is output as a current from the lead lines at both ends.
The integrated value of the current output from both ends, that is, the ratio of the amount of charges is proportional to the capacity divided at the pressurizing point. That is, Q
And Qx (1), Qx (2), Qy (1), Qy (2), the capacitances formed respectively are proportional to the square of the distance between the point where the pressure F is applied and the extraction electrode. . Therefore, the position coordinates are calculated as follows. (2x / Lx) ² = {Qx (2) -Qx (1)} / {Q
x (2) + Qx (1)} (2y / Lx) ² = {Qy (2) -Qy (1)} / {Q
y (2) + Qy (1)} In addition, when distortion occurs near the lead line, this amount may be corrected.

In the example of FIG. 12, the surface division type is used as the resistance of the resistance film, but the double side division type may be used. FIG. 14 is an example of an equivalent circuit when the bias voltage VB is set by using the surface split type, FIG. 16 is an example of an equivalent circuit when the counter is floating by using the surface split type, and FIG. It is an example of an equivalent circuit when a double-sided split type is used.

In the equivalent circuit using the surface division type, only the X coordinate side is shown for simplification, and the Y coordinate side is omitted because it is the same. (For the surface-divided type, the equivalent circuit on the Y coordinate side will be omitted in the same manner below.) When the charge amount is detected using a piezoelectric body, current flows only when the pressure changes, and the position is determined using the peak value of the charge amount. Detect coordinates. Therefore, it is necessary to accurately detect the current at the moment when the pressure changes. The resistance R of the resistance film adjusts the time constant of the current output, lowers the band of the pre-detection circuit, and reduces S /
It is priced to increase the N ratio. When inputting with pressure from a pen or a finger, the band may be set between 1 [kHz] and several [Hz]. This is mainly because it is difficult for a person to input at a speed of 1 [kHz] or more and that it is slow at a speed of several [Hz] or less. In particular, it is desirable to detect the liquid crystal at a drive frequency of 60 [Hz] in order to effectively reduce noise derived from the drive cycle.

21 and 23 are diagrams showing an example of the configuration of a coordinate detection circuit when a piezoelectric body is used. 22 and 24
FIG. 6 is a diagram showing an example of a configuration of a coordinate detection circuit when a thin film transistor in which a pressure sensitive body is connected to a gate is used. In FIG. 21, the output from the Q-V amplifier is A / D converted,
After that, coordinate calculation and peak detection are performed by digital calculation. At this time, it is effective in terms of improving the S / N ratio to remove the coupling noise with the common electrode at the time of common inversion by synchronizing with the clock of the liquid crystal display. Further, it is effective to correct the distortion in the vicinity of the lead line by digital calculation in terms of improving the position accuracy. In FIG. 23, addition, subtraction, division and peak hold may be subjected to analog processing, and finally A / D conversion may be performed. Also in this case, it is preferable to perform noise removal that depends on the driving cycle, correction of distortion near the lead line, and the like in the digital calculation after A / D conversion.

In FIG. 13, the pressure detecting element comprises a pressure sensitive body,
It is a figure for explaining an example of a coordinate calculation method at the time of detecting current or voltage. When pressure is applied to the pressure sensitive body, the resistance at the position where the pressure is applied decreases, and ideally shorts with the bias electrode. The bias voltage is resistance-divided by the resistance film and is output as a current or voltage from the lead lines at both ends. The ratio of the current output from both ends is inversely proportional to the resistance. Since the resistance is proportional to the distance from the lead wire,
The position coordinates are calculated as follows. (2x / Lx) ² = {Ix (2) -Ix (1)} / {I
x (2) + Ix (1)} (2y / Lx) ² = {Iy (2) -Iy (1)} / {I
y (2) + Iy (1)} In FIG. 13, the surface division type is used as the structure of the resistance film, but the double side division type may be used.

FIG. 15 shows an example of an equivalent circuit when the bias potential is set using the surface division type, and FIG. 18 shows an example of an equivalent circuit when the double side division type is used. 22 and 24 show examples of the coordinate detection circuit configuration when the pressure sensitive body is used. In the example of FIG. 22, the output from the IV amplifier is A / D converted, and then the coordinate calculation is performed by the digital calculation. At this time, it is effective in terms of improving the S / N ratio to remove the coupling noise with the common electrode at the time of common inversion by synchronizing with the clock of the liquid crystal display. Further, it is effective to correct the distortion in the vicinity of the lead line by a digital calculation from the viewpoint of improving the position accuracy. In the example of FIG. 24, an analog processing is performed up to addition, subtraction, and division, and finally A / D conversion is performed. Also in this case, it is effective to perform noise removal dependent on the pulse period and distortion correction in the vicinity of the leader line in the digital calculation after A / D conversion.

The method of calculating coordinates when detecting the current or the voltage is the same as that of the pressure sensitive body, since the pressure detecting element is composed of a piezoelectric gate transistor. FIG. 19 is a diagram showing an example of a surface division type equivalent circuit using a piezoelectric gate transistor, and FIG. 20 is a diagram showing an example of a double side division type equivalent circuit. In FIG. 19, the sources of the piezoelectric gate transistors are all set to a common potential (denoted by COM in the figure). A bias voltage that allows for ON / OFF margin of the TFT is applied to the piezoelectric gate (battery symbol in the figure). The polarity of the voltage generated when the piezoelectric body is compressed is determined by the polarization direction of the piezoelectric body.

In FIG. 20, the source / drain electrodes of the piezoelectric gate transistor are connected to resistance wirings for outputting the X-axis coordinates and the Y-axis coordinates, respectively. T for the piezoelectric gate
A bias voltage (V _{B in the} figure) that allows for the ON / OFF margin of the FT is applied. The polarity of the voltage generated when the piezoelectric body is compressed is determined by the polarization direction of the piezoelectric body. In both cases of FIG. 19 and FIG. 20, when pressure is applied to the piezoelectric body, the TFT at the position where the pressure is applied becomes the ON state,
It is resistance-divided by the resistance film, and is output as a current or voltage from the lead lines at both ends.

Next, the piezoelectric material used for the display device and its polarization treatment method will be described.

As the piezoelectric material, in addition to PZT, which is a typical piezoelectric material, for example, BaTiO ₃ , PbTiO ₃ and Bi are used.
₂ SrTa ₂ O ₉ , Bi ₃ Ti ₄ O ₁₂ , BaMgF ₄ ,
Gd ₂ (MoO ₄ ) ₃ or the like can be used. In order to exhibit piezoelectricity, it is necessary that the polarization directions are the same. To align the polarization directions, it is effective to apply a voltage to the piezoelectric material to invert the polarization. When the surface-division type bias electrode is formed, it is possible to align the polarization directions by applying a voltage larger than the piezoelectric polarization reversal voltage between the signal extraction electrode and the bias electrode. Similarly, in the case of the double-sided split type, it is possible to align the polarization directions by applying a voltage larger than that of the piezoelectric material between the opposing electrodes on both sides.

Further, in the case of the surface-divided type, in which the counter electrode is floating, the floating side is set to the air side, and while the ionizer is radiated, the electrode for signal extraction is referenced from the polarization reversal voltage of the piezoelectric body with reference to the ground potential. The polarization directions may be aligned by applying a large voltage.

When a piezoelectric body is used as the pressure detecting element, if at least one electrode of the piezoelectric body is in a floating state, a bias voltage may be applied to generate a high voltage, which may cause a short circuit. For example, when a piezoelectric gate thin film transistor using a piezoelectric body as a gate electrode is used as the pressure detection element, it is preferable to have a configuration for avoiding such a short circuit. For example, a protection circuit for protection when an excessive voltage is generated may be connected to one floating electrode of the piezoelectric body. As such an example, for example, the configuration illustrated in FIG. 8 can be cited. Since both can be composed of thin film transistors,
The thin film transistor for pixel selection can be formed at the same time. Therefore, it is possible to avoid a decrease in the productivity of the liquid crystal display device due to the formation of the protection circuit.

[0051]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. (Embodiment 1) FIG. 1 is a diagram schematically showing an example of the configuration of a liquid crystal display device of the present invention. The liquid crystal display device of FIG. 1 is a liquid crystal display device having a coordinate input function, and as a liquid crystal display system, a thin film transistor (TFT) is used.
An active matrix method using an mTransistor is used. In addition, as a liquid crystal display mode, a transmissive TN (Twisted Nematic) is used.
c) method is used. A piezoelectric body is used as a pressure-sensitive element for pressure detection.The electrode structure of the pressure-sensitive element is a surface division type, and the bias electrode also functions as a common electrode for liquid crystal display. Furthermore, the resistance film also functions as a black matrix (Fig. 1
1 (a)). This liquid crystal display device includes an array substrate 11
The liquid crystal layer 13 is sandwiched between the counter substrate 12 and the counter substrate 12. The gap between the array substrate 11 and the counter substrate 12 is held by a columnar spacer 14. The array substrate 11 is
Insulating substrate 15 such as a glass substrate and this insulating substrate 1
5 are provided with pixel electrodes 16 arranged in a matrix, and thin film transistors 17 for applying a voltage corresponding to a display signal to the pixel electrodes 16. An alignment film (not shown) is provided on the sandwiching surface of the liquid crystal layer 13 between the array substrate 11 and the counter substrate 12. The thin film transistor 17 is
A gate electrode 17g provided on the insulating substrate 15, a gate insulating film 18 provided so as to cover the gate electrode 17g, and, for example, a-Si facing the gate electrode 17g via the gate insulating film 18, Semiconductor film 17i such as p-Si
And the source electrode 17s and the drain electrode 17d joined to the semiconductor film 17i, the channel protection film 17e, and the passivation film 1 provided so as to cover the thin film transistor.
9 and 9. A contact layer (not shown) made of n ⁺ a-Si or the like is provided on the surface of the semiconductor film 17i that is in contact with the source / drain electrodes so that the source / drain electrodes and the semiconductor film are in ohmic contact.

The counter substrate 12 is an insulating substrate 21 such as a glass substrate, a resistance film 22 arranged on the insulating substrate 21 in a predetermined pattern complementary to the pixel electrodes, the resistance film 22 and a spacer. Pressure-sensitive element 2 disposed between
3, a color filter 24 arranged so as to cover the resistance film 22 and the pressure sensitive element 23, and a common electrode (counter electrode) 25 arranged on the liquid crystal layer sandwiching surface. In this example, the resistance film 22 is made of a material having a light-shielding property, and is configured so as to also function as a black matrix that shields light between adjacent pixel regions. The color filter 24 is arranged so as to cover each pixel region with an insulating material colored in three primary colors of additive colors of R (red), G (green), and B (blue).

The coordinate calculation method in this structure is shown in FIG.
2 and the equivalent circuit is as shown in FIG. Also,
The configuration example of the coordinate detection circuit is as described in FIGS. 21 and 23, and the coordinate detection circuit when the configuration example of the coordinate detection circuit in FIG. 23 is used is as shown in FIG. That is, when pressure is applied to the counter substrate 12, the pressure sensitive element is pressurized and outputs an electric signal such as induced charge, current, or voltage. And as mentioned above, based on this electrical signal,
The position on the display screen where pressure is applied is detected. In the liquid crystal display device of the present invention, the addition of the position detection function can be arranged complementarily to each pixel region contributing to display. Further, unlike the conventional liquid crystal display device, it is not necessary to dispose electrodes for position detection in a region that contributes to display. Further, it is possible to perform highly accurate position detection without displacement of the detected position due to parallax or the like.

Next, an example of a method of manufacturing the above-mentioned liquid crystal display device will be described. First, a method of manufacturing the array substrate 11 will be described.

First, a Mo—Ta alloy having a thickness of 300 nm is deposited on the insulating substrate 15 and patterned to form the gate line and the gate electrode 17 continuous with the gate line.
g and an auxiliary capacitance line (not shown) are formed at the same time. Next, a silicon oxide film having a thickness of 400 nm and SiNx is formed.
Is deposited to a thickness of 50 [nm], a-Si is deposited to a thickness of 50 [nm], and etching stopper layer SiNx is deposited to a thickness of 200 [nm]. After the resist application, backside exposure and normal exposure are performed to self-align Si on the gate line only.
The stopper layer 17e made of Nx is left and the others are etched. Next, n ⁺ a-S which becomes an ohmic contact layer
i is deposited to a thickness of 50 [nm] and the n ⁺ a-Si layer / a-Si layer / SiNx layer is collectively patterned to form a semiconductor film 17i and a contact layer.

Next, ITO (indium tin oxide) is deposited to a thickness of 100 [nm] and patterned to form the pixel electrode 16. Further, the oxide film on the lead line (not shown) is patterned to form a through hole.

Next, Cr80 [nm] and Al30 [n]
m], Cr 80 [nm], and patterning are performed to deposit the signal line and the source electrode 17 of the thin film transistor.
and the drain electrode 17d is formed. And Cr / A
RIE (Reactive I) with 1 / Cr as a mask
on Etching) to remove the unnecessary n ⁺ a-Si layer other than the contact region.

Then, SiNx is deposited to a thickness of 20 [nm] and patterned to form a passivation film 19 on the portion other than the pixel electrodes of the array substrate.

Next, a method of manufacturing the counter substrate will be described.

First, C is placed on an insulating substrate 21 such as glass.
By depositing r of 30 [nm] and patterning, the resistance film 22 which also serves as a black matrix is formed. Next, PZT, which is a piezoelectric substance, is deposited to a thickness of 1 [μm] by a sputtering method or the like, and is patterned into a shape complementary to the pixel region by mask exposure and dry etching of a resist.

Then, a color filter is formed by repeating application of a pigment dispersion resist for 2 [μm] and patterning for three colors of red, green and blue. Next, ITO, which is a transparent electrode, is formed to a thickness of 15 by mask sputtering.
By depositing 0 [nm], the common electrode 25 which also serves as a bias electrode for the resistance film is formed.

Next, a method of manufacturing a liquid crystal cell will be described.

First, on the counter substrate 12, an alignment film made of polyimide or the like for controlling the alignment of liquid crystal molecules is formed to a thickness of 70 nm by a printing method and baked. A rubbing process is performed on this alignment film to define the alignment direction of the liquid crystal.

Thereafter, in order to form the spacer 14, for example, an acrylic resist is applied, mask exposure, development, and baking are performed, so that the insulating spacer 14 is selectively formed in a region corresponding to the pressure sensitive element 23 made of a piezoelectric material. To form.

On the other hand, the array substrate 11 is also subjected to the printing, firing and rubbing treatment of the alignment film as in the counter substrate 12. Then, the sealing material is applied to the counter substrate 12 and dried. The sealant plays a role of bonding the signal line side substrate and the scanning line side substrate to form a liquid crystal reservoir. Next, an ultraviolet curable resin (temporary fixing agent) that plays a role of suppressing misalignment at the time of sealing is applied to the outside of the seal of the counter substrate 12, and the array substrate 11 and the counter substrate 12
Assemble so that the alignment film forming surfaces of are opposed to each other. Next, the array substrate and the counter substrate are aligned (correction of misalignment), and the temporary fixing position is irradiated with ultraviolet rays to cure the temporary fixing agent. Then, the sealing agent is cured by heating in the oven while loading the entire surface of the cell.

After that, the liquid crystal composition is injected by immersing the liquid crystal composition in a portion (injection port) where the sealant is opened in a vacuum state. Next, an ultraviolet curing agent is attached to the injection port, and the injection port is sealed by irradiating with ultraviolet light.

Next, this liquid crystal cell is heated in an oven,
By cooling, the orientation of the liquid crystal is made uniform. Finally, polarizing plates are adhered to the surfaces of the substrates on both sides of the liquid crystal cell so as to be parallel or perpendicular to the rubbing direction thereof.

(Embodiment 2) As the pressure sensitive element 23 of the liquid crystal display device illustrated in FIG. 1, a pressure sensitive body whose resistance value changes with pressure is used as the pressure sensitive element instead of the piezoelectric material. Configured. FIG. 13 shows a coordinate coordinate calculation method in this structure, and FIG. 15 shows an equivalent circuit. 22 and 24 show an example of the configuration of the coordinate detection circuit, and FIG. 26 shows an embodiment of the coordinate detection circuit when the example of the configuration of the coordinate detection circuit of FIG. 24 is used.

The manufacturing method is also the same as that in the first embodiment except that the fine metal particle-dispersed resist, which is a pressure sensitive body, is applied and patterned by exposure / development instead of the piezoelectric body forming process, and therefore the description thereof is omitted. To do.

(Embodiment 3) FIG. 2 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention.

The structure and function of the liquid crystal display device illustrated in FIG. 2 will be described with reference to the drawings. In the liquid crystal display device of FIG. 2, a thin film transistor (TFT: Thin Film Transistor) is used as a liquid crystal display method.
The active matrix method using r) is used. As a liquid crystal display mode, a transmissive TN (T
The Wisted Nematic) method is used. A piezoelectric body is used as the pressure sensitive element 23, and the structure thereof is a surface division type, and the black matrix 31 also functions as a bias electrode. The black matrix 31 and the common electrode 25 are brought into contact with each other to be electrically connected. Here, the black matrix 31 plays a role of compensating for the increased resistance of the common electrode 25 due to the patterning. The resistance film 22 (see FIG. 10) is made of the same layer as the common electrode 25, and both are insulated by being patterned. Resistance film 22
The pattern is formed in the non-opening portion facing the black matrix 31. The coordinate coordinate calculation method, the equivalent circuit, and the configuration example of the coordinate detection circuit in this structure are the same as those in the first embodiment, and therefore description thereof is omitted here.

Next, an example of a method of manufacturing the liquid crystal display device of the present invention illustrated in FIG. 2 will be described. Array substrate 11
The manufacturing method of can be manufactured in the same manner as the manufacturing method described in the first embodiment.

Regarding the method of manufacturing the counter substrate, first, Cr is deposited to a thickness of 500 nm on the insulating substrate 21 and patterned to form the black matrix 31. Next, PZT, which is a piezoelectric substance, is deposited to a thickness of 1 [μm] by sputtering, and the piezoelectric substance 23 is patterned by mask exposure and dry etching of a resist. Next, the color filter 24 is formed by repeating 21 [μm] application of a pigment-dispersed resist and patterning for red, green, and blue colors. Next, ITO, which is a transparent electrode, is deposited to a thickness of 150 [nm] by a sputtering method or the like, and the ITO is patterned by mask exposure and wet etching of a resist.
And the resistance film 22 are simultaneously formed.

The manufacturing method of the liquid crystal cell is the same as that of the first embodiment, and therefore the description thereof is omitted here.

(Embodiment 4) As the pressure sensitive element 23 of the liquid crystal display device illustrated in FIG. 2, a pressure sensitive body whose resistance value changes with pressure is used as the pressure sensitive element instead of the piezoelectric material. Configured. The method of calculating coordinate coordinates in this structure is the same as in the second embodiment. The manufacturing method is also the same as that of the first embodiment except that the fine metal particle-dispersed resist, which is a pressure sensitive body, is applied and patterned by exposure / development instead of the piezoelectric body forming process, and therefore the description thereof is omitted.

(Embodiment 5) FIG. 3 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention. The structure and function of the liquid crystal display device illustrated in FIG. 3 will be described with reference to the drawings.

In the liquid crystal display device with a coordinate input function shown in FIG. 3, a thin film transistor (TF) is used as a liquid crystal display system.
An active matrix method using T: Thin Film Transistor is used. In addition, as a liquid crystal display mode, a transmissive TN (Twis
Ted Nematic) method is used. A piezoelectric body is used as the pressure-sensitive element, and the structure thereof is a surface division type, and the bias electrode also functions as a common electrode for forming an electric field in the liquid crystal layer together with the pixel electrode (see FIG. )reference). The resistance film 22 (see FIG. 10) is formed in the same layer as the pixel electrode 16 on the array substrate 15 side, and both are separately patterned so as to be insulated. The pattern of the resistive film 22 is the black matrix 3
1 is formed in a non-opening portion so as not to overlap the pixel electrode 16 (see FIG. 10).

That is, in this example, the resistance film 22 is arranged on the array substrate 11 side, and pressure is applied by detecting an electric signal of the pressure sensitive element 23 made of, for example, a piezoelectric material through the resistance film 22. Detect the position coordinates.

Further, in this example, a part of the spacer for holding the gap between the array substrate 11 and the counter substrate 12 is composed of a color filter. That is, the RGB color filters 24R, 24G, and 24B are sequentially formed. At this time, the color filter 24R and the color filter 24B are arranged so as to partially overlap each other, and the color filter 24B and the color filter 24G are further arranged. By arranging and so as to partially overlap with each other, the loft of the overlapping portion is increased. By adopting such a configuration, the step of individually forming the spacer can be omitted,
Productivity can be improved.

Also in the liquid crystal display device illustrated in FIG. 3,
The coordinate calculation method, the equivalent circuit, and the configuration example of the coordinate detection circuit are the same as those in the first embodiment, and are omitted here.

Here, an example of a method of manufacturing the liquid crystal display device illustrated in FIG. 3 will be described. The manufacturing method of the array substrate 11 is the same as that of the first embodiment except that the resistive film pattern is formed at the same time as the pixel electrode 16, and thus the description thereof is omitted here.

Next, a method of manufacturing the counter substrate will be described. First, 50 [nm] of Cr is deposited on the insulating substrate 21 and patterned to form the black matrix 31. Next, the pigment-dispersed resist is set to 2 μm.
By repeating coating and patterning for the three colors of red, green and blue, the color filters 24R, 24
B and 24G are formed. At this time, a part of the spacer is shared by the color filter resist by leaving the resist corresponding to the spacer overlapping.

After that, ITO, which is a transparent electrode, is deposited to a thickness of 15 nm by a sputtering method or the like, and the common electrode 25
To form.

The manufacturing method of the liquid crystal cell is the same as the above except that the resist in which the piezoelectric fine particles are dispersed is used as the spacer material, and therefore the description thereof is omitted here.

(Embodiment 6) As the pressure sensitive element 23 of the liquid crystal display device illustrated in FIG. 3, a pressure sensitive body whose resistance value changes with pressure is used as the pressure sensitive element instead of the piezoelectric material. Configured. The method for calculating coordinate coordinates in this structure is the same as described above. Also, the manufacturing method is the same as that of the above-described embodiment except that a metal fine particle-dispersed resist that is a pressure sensitive body is applied instead of the piezoelectric body forming process, and patterning is performed by exposure / development. Omit it.

(Embodiment 7) FIG. 4 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention. The structure and function of the liquid crystal display device of the present invention illustrated in FIG. 4 will be described with reference to the drawings. In the liquid crystal display device with a coordinate input function of FIG. 4, a thin film transistor (TFT) is used as a liquid crystal display system.
or)) is used. The liquid crystal display mode is a transmissive TN.
(Twisted Nematic) method is used. A piezoelectric body is used as the pressure-sensitive element, the structure is a surface division type, the bias electrode 26 is formed of the same layer as the gate electrode 17i of the thin film transistor, and both are insulated by patterning. The resistance film 22 (see FIG. 10) is made of the same material and in the same layer as the pixel electrode 16, and both are insulated by being patterned. The resistive film 22 pattern is formed in the non-opening portion facing the black matrix 31 (FIG. 1).
0).

That is, in the liquid crystal display device of the present invention illustrated in FIG. 4, the pressure sensitive element 23 is arranged in a region of the array substrate 11 facing the spacer 14. Spacer 1
A resistance film 22 is sandwiched between the pressure sensor 4 and the pressure sensitive element 23. A bias electrode 26 is provided on the surface of the pressure sensitive element 23 opposite to the resistance film 22.

The coordinate coordinate calculation method, the equivalent circuit, and the configuration example of the coordinate detection circuit in the liquid crystal display device having such a configuration are the same as those in the above-described embodiment, and therefore the description thereof is omitted here.

Here, an example of a method of manufacturing the liquid crystal display device of the present invention illustrated in FIG. 4 will be described. First, a method of manufacturing the array substrate 11 will be described.

First, glass, non-alkali glass, quartz,
A Mo—Ta alloy having a thickness of 300 [nm] is deposited on the insulating substrate 15 made of resin or the like and patterned to simultaneously form the gate electrode 17g, the gate line, the bias electrode 26, and the auxiliary capacitance line (not shown).

Next, PZT, which is a piezoelectric material, is deposited to a thickness of 11 [μm] by sputtering, and the piezoelectric body 23 is patterned by mask exposure and dry etching of a resist.

Then, a silicon oxide film SiNx is formed to a thickness of 4
00 [nm], silicon nitride film SiNx with a thickness of 50 [n]
m], an a-Si semiconductor film having a thickness of 50 [nm], and an etching stopper SiNx having a thickness of 200 [nm] are deposited.

Next, after resist application, back surface exposure and normal exposure are performed to leave the SiNx stopper layer 17e only on the gate lines and to etch the rest. Next, n ⁺ a-Si to be a contact layer is deposited [nm], and n ⁺ a-Si is deposited.
Layers / a-Si layer / SiNx layer are collectively patterned to form a-Si islands.

Next, Cr80 [nm], Al [nm], C
A signal line, a source electrode 17s of the thin film transistor, and a drain electrode 17d are formed by depositing and patterning r80 [nm].

Then, using R / Al / Cr as a mask, R
By performing IE (Reactive Ion Etching), the n ⁺ a-Si layer other than the contact region is removed.

Next, the oxide film on the piezoelectric body 23 and the oxide film on the lead line (not shown) are patterned to form through holes. Next, apply acrylic resist to a thickness of 2
[Μm] is applied and patterned to form a passivation film 19 having a contact hole between it and the source electrode.

Then, a pixel electrode 16 is formed by depositing ITO to a thickness of 100 nm by a sputtering method or the like and patterning it.

Next, a method of manufacturing the counter substrate will be described.

First, the black matrix 31 is formed by depositing Cr on the insulating base plate 21 having a light transmitting property such as glass in a thickness of 500 nm and patterning it.

Next, ITO, which is a transparent conductive material, is deposited to a thickness of 150 nm by a sputtering method or the like, and the common electrode 25 is formed.
To form.

The manufacturing method of the liquid crystal cell is the same as that of the first embodiment, and the description thereof is omitted here.

(Embodiment 8) As the pressure sensitive element 23 of the liquid crystal display device illustrated in FIG. 4, a pressure sensitive body whose resistance value changes with pressure is used as the pressure sensitive element instead of the piezoelectric material. Configured. The method for calculating coordinate coordinates in this structure is the same as described above. Also, the manufacturing method is the same as that of the above-described embodiment except that a metal fine particle-dispersed resist that is a pressure sensitive body is applied instead of the piezoelectric body forming process, and patterning is performed by exposure / development. Omit it.

(Embodiment 9) FIG. 5 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention. The structure and function of the liquid crystal display device illustrated in FIG. 5 will be described with reference to the drawings. In the liquid crystal display device with a coordinate input function shown in FIG. 5, a simple matrix system in which stripe electrodes are opposed to each other is used as a liquid crystal display system. In addition, as a liquid crystal display mode, a transmissive STN (Super) is used.
The Twisted Nematic) method is used. A piezoelectric body is used as the pressure sensitive element 23, and the electrode structure of the pressure sensitive element is a surface division type (see FIG. 9A).
The resistance film 22 also functions as a black matrix. The coordinate coordinate calculation method in this structure is shown in FIG.
The equivalent circuit is shown in FIG. 16, and the configuration example of the coordinate detection circuit is as shown in FIGS. Further, FIG. 25 shows an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 23 is used.

The liquid crystal display device illustrated in FIG. 5 is a simple matrix type liquid crystal display device, and a liquid crystal layer is provided between the substrate 15 on which the scanning electrodes 41 are arranged and the substrate 21 on which the signal electrodes 42 are arranged. 13 is sandwiched. The scanning electrodes 41 made of a transparent insulating material such as ITO are arranged, for example, in a stripe shape on the substrate 15 made of an insulating material such as glass. Further, the pattern of the resistance film 22 which also serves as the black matrix as described above is arranged on the substrate 21. A piezoelectric body 23 is sandwiched between the resistance film 22 and the spacer 14, and when pressure is applied to the liquid crystal cell, an induced charge is generated on the surface of the liquid crystal cell in response to the pressure. The induced charges are extracted outside the display area through the resistance film 22 and signal processing for position detection is performed. Further, the color filter 24 is arranged from above the resistance film 22, and the signal electrode 42 is arranged above this color filter 24.

As described above, the present invention can be applied not only to the active matrix type liquid crystal display device but also to a simple matrix type liquid crystal display device.

Now, a method of manufacturing the liquid crystal display device of the present invention illustrated in FIG. 5 will be described. First, a method of manufacturing the substrate 21 will be described.

First, Cr is deposited on the insulating substrate 21 in a thickness of 300 [nm], and patterning is performed.
A resistance film 22 that also serves as a black matrix is formed. Next, PZT as a piezoelectric body 23 is deposited by sputtering over a thickness of 11 [μm], and patterned by mask exposure and dry etching of a resist.

Further, the pigment-dispersed resist is 21 [μm].
The color filter 24 is formed by repeating coating and patterning for three colors of red, green and blue.

After that, for example, ITO is used as a transparent conductive film.
Is deposited for 150 [nm] and patterned to form the signal electrode 42 for driving the liquid crystal.

Next, a method of manufacturing the substrate 15 will be described. First, 1 ITO on the glass substrate, which is a transparent electrode,
The scanning electrode 41 for driving the liquid crystal is formed by depositing 50 [nm] and patterning.

The manufacturing method of the liquid crystal cell is the same as that of the above-mentioned embodiment, and the description thereof is omitted here.

(Embodiment 10) FIG. 6 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention. The structure and function of the liquid crystal display device of the present invention illustrated in FIG. 6 will be described with reference to the drawings.

In the liquid crystal display device of the present invention having the coordinate input function illustrated in FIG. 6, the liquid crystal display method is as follows.
A simple matrix method in which stripe electrodes are opposed to each other is used. In addition, as a liquid crystal display mode, a transmissive STN (Super Twisted Nematic) is used.
c) method is used. The liquid crystal display device illustrated in FIG. 6 is also a simple matrix type liquid crystal display device, and includes a substrate 15 on which scan electrodes 41 (not shown) are arranged, and signal electrodes 42
The liquid crystal layer 13 is sandwiched between the liquid crystal layer 13 and the substrate 21 on which is disposed. The scanning electrodes 41 made of a transparent insulating material such as ITO are arranged, for example, in a stripe shape on the substrate 15 made of an insulating material such as glass. The resistance film 22b is arranged in parallel with the scan electrode 41 and insulated from the scan electrode 41. Further, the pattern of the black matrix 31 as described above is arranged on the substrate 21. Further, in this example, the spacer is composed of the piezoelectric body 23, and the resistive film 22 is sandwiched between the resistive film 22 and the spacer composed of the piezoelectric body 23. When a pressure is applied to the liquid crystal cell, an induced charge is generated on the surface of the piezoelectric body according to the pressure. The induced charge is the resistance film 2
Signals are taken out from the outside of the display area through 2 and signal processing for position detection is performed. Further, the color filter 24 is arranged from the upper side of the substrate 21, and the signal electrode 42 is arranged above the color filter 24.

As described above, in this example, the spacer also serves as a pressure detecting element, and the constituent material thereof is the piezoelectric body 2.
3 is used, and the electrode structure of the pressure detection element is a double-sided split type (see FIG. 11B). Resistance film 22
Are formed of the same material and in the same layer as the signal electrode 42, and both are insulated by being patterned. Similarly, the scanning electrode 41 and the resistance film 22b are formed of the same layer,
Both are insulated by being patterned.
Further, both the resistance film 22 and the resistance film 22b are selectively formed only in the portion shielded by the black matrix 31.

FIG. 1 shows the coordinate calculation method in this structure.
2 (in FIG. 12, a schematic view of the surface division type is shown,
The calculation method is the same. ), The equivalent circuit is shown in FIG.
Shown in. 21 and 23 show a configuration example of the coordinate detection circuit.
25 shows an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 23 is used.

Next, a method of manufacturing the liquid crystal display device of the present invention illustrated in FIG. 6 will be described.

First, a method of manufacturing the substrate 21 will be described.

First, on a substrate 21 made of glass or the like,
The black matrix 31 and the color filter 24 are formed by repeating application of a pigment dispersion resist for 2 [μm] and patterning for four colors of black, red, green and blue. Then, ITO, which is a transparent electrode, is
m] are deposited and patterned to simultaneously form the signal electrode 42 for driving the liquid crystal and the resistance film 22.

Next, a method of manufacturing the substrate 15 will be described.

First, on the substrate 15 made of glass or the like,
ITO, which is a transparent electrode, is deposited to a thickness of 150 nm and patterned to form the scanning electrode 41 and the resistance film 22b at the same time. The manufacturing method of the liquid crystal cell is the same as that of the above-described embodiment, and thus the description thereof is omitted here.

(Embodiment 11) Next, another example of the liquid crystal display device of the present invention will be described.

In the liquid crystal display device illustrated in FIG. 6, a piezoelectric body is used as a pressure sensitive element for detecting pressure, but in this example, a pressure sensitive body is used. A coordinate calculation method in this structure is shown in FIG. 13 (a surface division type schematic is shown in FIG. 13, but the calculation method is the same), and an equivalent circuit is shown in FIG. In addition, a configuration example of the coordinate detection circuit is shown in FIG.
FIG. 26 shows an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 24 is used in FIG.

(Embodiment 12) FIG. 7 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention. First, the structure and function of the liquid crystal display device with a coordinate input function according to the twelfth embodiment of the present invention will be described with reference to the drawings. In the liquid crystal display device of FIG. 7, as a liquid crystal display method, MIM (Metal Insulator Me) is used.
The active matrix method using the (Tal) element 40 is used. That is, ON / OFF is controlled according to the potential applied to the signal line 43, and the display signal is applied to the pixel electrode 16 when ON.

As the liquid crystal display mode, a transmissive TN (Twisted Nematic) system is used. A piezoelectric body 23 is used as the pressure detecting element, the electrode structure of the pressure detecting element is a surface-divided type, and the resistance film 22 also functions as a black matrix (see FIGS. 11A and 10). . Also, the bias electrode 2
6 has a structure in which the same layer as the pixel electrode 16 and the same layer as the upper electrode 40a of the MIM 40 are stacked, and the bias electrode 26 and the pixel electrode 16 and the bias electrode 26 and the MIM upper electrode 40a are insulated by being patterned. There is.

FIG. 12 shows the coordinate calculation method in this structure.
14 shows an equivalent circuit. 21 and 23 show a configuration example of the coordinate detection circuit, and FIG. 25 shows an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 23 is used.

Next, a method of manufacturing a liquid crystal display device with a coordinate input function according to the twelfth embodiment of the present invention will be described. First, a method of manufacturing the array substrate 11b having the MIM will be described.

First, T is placed on an insulating substrate 15 such as glass.
The signal line 43 is formed by depositing a with a thickness of 500 nm and patterning. Subsequently, a tantalum oxide film is deposited to a thickness of 300 [nm]. Next, add Cr to a thickness of 4
By depositing 00 [nm] and patterning, M
The IM upper electrode 40a and the bias electrode 26 are formed simultaneously. Next, ITO is deposited to a thickness of 100 nm and patterned to simultaneously form the pixel electrode 16 and the bias electrode.

Next, the piezoelectric fine particle dispersed resist is set to 2 [μ
m] is applied, and patterning is performed by exposure and development to form and pattern the piezoelectric body 23. Next, by applying 2 [μm] of the pigment dispersion resist and performing patterning for three colors of red, green and blue,
The color filter 24 is formed. After this, add Cr to a thickness of 3
A pattern of the resistance film 22 which also serves as a black matrix is created by depositing it at 00 [nm] and patterning it.

Next, a method of manufacturing the counter substrate 12b will be described. The scanning electrode 41 is formed by depositing ITO, which is a transparent electrode, on the glass substrate 21 to a thickness of 150 [nm] and patterning it.

The manufacturing method of the liquid crystal cell is the same as that of the above-mentioned embodiment, and therefore the explanation is omitted here.

(Embodiment 13) Next, a modification of the liquid crystal display device of the present invention illustrated in FIG. 7 will be described. In this example, the liquid crystal display device of the present invention illustrated in FIG. 7 is used, except that a pressure sensitive element whose resistance value changes according to pressure is used instead of the piezoelectric body 23 as the pressure detection element. It has a similar structure. FIG. 13 shows a coordinate calculation method in this structure, and FIG. 15 shows an equivalent circuit. 22 and 24 show an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 24 is used.
6 shows.

The manufacturing method is the same as that of the twelfth embodiment, except that instead of the piezoelectric body forming process, a metal fine particle dispersed resist which is a pressure sensitive body is applied and patterned by exposure and development.

(Embodiment 14) FIG. 8 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention. The configuration and functions of the liquid crystal display device having the coordinate input function of the present invention illustrated in FIG. 8 will be described with reference to the drawings.

In the liquid crystal display device of the present invention illustrated in FIG. 8, a thin film transistor (TF) is used as a liquid crystal display system.
An active matrix system using T: Thin Film Transistor is used. In addition, as a liquid crystal display mode, a transmissive TN (Twis
Ted Nematic) method is used. A piezoelectric gate transistor is used as the pressure detecting element, and the electrode structure of the pressure detecting element is a surface division type. The equivalent circuit of this structure is shown in FIG. In FIG. 8, the gate line 17g of the thin film transistor 17 for driving the liquid crystal, the gate bias line 51 of the piezoelectric gate TFT 50, the bias electrode 2
6 is composed of the same layer, and the three are insulated by patterning. In addition, the channel semiconductor film 17i (for example, a-
Si) and the channel semiconductor film 50i of the piezoelectric gate TFT
(A-Si) is composed of the same layer, and both are insulated by being patterned. The resistance film 22 is formed of the same layer as the pixel electrode 16, and both are insulated by being patterned. Then, when pressure is applied, the piezoelectric body 23 is pressed by the spacer 14, and the channel semiconductor film 50i of the thin film transistor 50 becomes conductive. At this time, the bias electrode 26 and the resistance film 22 have the same potential through the drain electrode 50d. Therefore,
In the equivalent circuit illustrated in FIG. 19, Ix (1), Ix (2), Iy (1), and Iy (2) are divided at the point where they are in a conductive state, so that the coordinates under pressure can be detected. it can. In addition,
By applying an appropriate bias to the piezoelectric body 23 by the gate bias electrode 51, the sensitivity of the pressure detection element with respect to the applied force can be adjusted.

FIG. 13 shows a coordinate calculation method in this structure, and FIG. 15 shows an equivalent circuit in which the piezoelectric gate transistor is shown as a switch. 22 and 24 show a configuration example of the coordinate detection circuit, and FIG. 26 shows an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 24 is used.

Now, a method of manufacturing the liquid crystal display device of the present invention illustrated in FIG. 8 will be described. First, a method of manufacturing the array substrate will be described.

First, a Mo-Ta alloy having a thickness of 300 [nm] is deposited on a glass substrate and patterned to form a gate electrode 17g, a gate line, a gate bias line 51 of the piezoelectric gate TFT, a bias electrode of the piezoelectric gate TFT. Two
6 and an auxiliary capacitance line (not shown) are formed at the same time.

Next, PZT as the piezoelectric body 23 is deposited to a thickness of 1 [μm] by sputtering, and patterned by mask exposure and dry etching of a resist. Then, a silicon oxide film SiOx is deposited to a thickness of 400 nm and patterned to pattern the oxide film on the piezoelectric body 23 and on the lead line (not shown) to form a through hole.

Next, SiNx is added to a thickness of 50 [nm], a
-Si semiconductor film having a thickness of 50 nm, Si for i stopper
Nx is deposited to a thickness of 200 nm. Next, after the resist is applied, back surface exposure and normal exposure are performed to leave the stopper layer 17e made of SiNx in a self-aligned manner only on the gate electrode 17g of the thin film transistor 17, and the rest is removed by etching. Next, n ⁺ a-Si is set to 50 [n
m] is deposited and the n ⁺ a-Si layer / a-Si layer / SiNx layer is collectively patterned to simultaneously form the islands of the p semiconductor film 17i of the thin film transistor 17 and the semiconductor film 50i of the piezoelectric gate TFT.

Next, Cr is 80 [nm] and Al is 350 nm.
[Nm] and Cr of 80 [nm] are deposited and patterned to form the signal line, the source electrode 17s of the thin film transistor 17, the drain electrode 17d, and the piezoelectric gate TFT5.
The drain electrode 50d of 0 is simultaneously formed.

Next, using R / Al / Cr as a mask, R
By performing IE (Reactive Ion Etching), n ⁺ a-S in a portion other than the contact region is removed.
Remove i-layer. Next, a pigment dispersion resist is applied in a thickness of 2 [μm], and exposure and development are repeated for red, green, and blue to form a color filter 24. Then, ITO is deposited to a thickness of 100 nm and patterned to form the pixel electrode 16 and the resistance film 33 at the same time.

Next, a method of manufacturing the counter substrate 12 will be described. First, Cr [300 [n] is applied on the glass substrate 21.
m] The black matrix 31 is formed by depositing and patterning.

Next, ITO as a transparent conductive material is deposited by mask sputtering to a thickness of 150 nm,
The common electrode 25 is formed. The manufacturing method of the liquid crystal cell is the same as that of the above-described embodiment except that the spacer is formed on the array substrate.

(Fifteenth Embodiment) In the fourteenth embodiment, an example has been described in which the electrode structure of the pressure detecting element is a surface-divided type, but it may be a double-sided divided type as described above.

FIG. 20 shows an example of an equivalent circuit when the electrode structure of the pressure detecting element is a double-sided type. In this case, in the liquid crystal display device illustrated in FIG. 8, the gate electrode 17g of the liquid crystal driving thin film transistor 17 and the gate bias line 51 of the piezoelectric gate thin film transistor are formed of the same layer,
Both are insulated by being patterned. Also, the channel semiconductor film 17i (a-Si) of the liquid crystal driving thin film transistor 17, the channel semiconductor film 50i (a-Si) of the piezoelectric gate thin film transistor, and the resistance film pattern 22b are formed of the same layer, and the three are patterned respectively. Insulated by

The resistance film 22 is formed in the same layer as the pixel electrode 16, and both are insulated by patterning (see FIG. 10).

Further, FIG. 13 shows a coordinate calculating method in this structure, and FIG. 15 shows an equivalent circuit in which the piezoelectric gate transistor is shown as a switch. 22 and 24 show a configuration example of the coordinate detection circuit, and FIG. 26 shows an embodiment of the coordinate detection circuit when the configuration example of the coordinate detection circuit of FIG. 24 is used.

Next, a method of manufacturing a liquid crystal display device when the electrode structure of the pressure detecting element is a double-sided type will be described.
Regarding the manufacturing method of the array substrate 11, the gate line and the gate electrode 17g, the gate bias line 51, and the auxiliary capacitance line (not shown) are formed simultaneously, and the thin film transistor 1
7 semiconductor film 17i, piezoelectric gate thin film transistor 50
Semiconductor film 50i TFT a-Si island, resistance film 22b
Is the same as the fourteenth embodiment except that are simultaneously formed. The counter substrate manufacturing method and the liquid crystal cell manufacturing method can be performed in the same manner as in the fourteenth embodiment.

In the above-mentioned embodiment, the liquid crystal display device has been described as an example, but the present invention is not limited to the liquid crystal display device, and other types of flat panel such as a field emission display and a plasma addressed liquid crystal display device can be used. It can also be applied to a mold display device.

(Embodiment 16) In the above-described example, an example in which the position detection is performed by detecting the current output from the pressure detection element has been described as the position detection method, but it is applicable to the liquid crystal display device of the present invention. The position detection method is not limited to this. Here, another example of the position detection method will be described.

FIG. 27 is a diagram showing an example of the configuration of a display device having a pen input function. In FIG. 27, 195 is a resistance film, 196 is a resistance film, 197 is a conductive layer provided on the resistance film 195, and 198 is the resistance film 1.
Reference numeral 96 denotes a conductive layer provided on the resistance film 196, 5 denotes a conductive layer provided on the resistance film 196, 200 denotes a conductive layer provided on the resistance film 196, and SW1 and SW2 denote CNTs.
1 is a switch controlled by 1, SW3 and SW4 are switches controlled by CNT2, 204 is a voltage source for supplying a constant voltage to each resistance film, and 5 V is supplied here. The impedance conversion unit 202 includes the conductive layer 19
8 and the conductive layer 6 detect an analog electric signal from the detection pen 20.
After impedance conversion is performed on the X-direction signal and the Y-direction signal indicating the position of the display device 10 ′ of No. 5 on the display device 10 ′, X ′ and Y ′.
And 203 is an A / D converter that converts analog signals X ′ and Y ′ into DX and DY digital signals, respectively. The operation of each of the components described above will be described later.
9, No. 12 ”etc. The movement vector direction (X
Direction, Y direction) is as shown in FIG.

FIG. 28 is a diagram for explaining the principle of the pen coordinate detecting device. FIG. 28A shows a sectional view of a tablet formed of the resistance films 195 and 196.
Reference numeral 13 is a spacer for keeping the resistance films 195 and 196 in contact with each other when the pen is not input. In this way, the resistance film 1
When the detection pen pressure is not applied to 95 and 196, the resistance films 195 and 196 maintain the non-contact state.

FIG. 28B is a diagram showing a state in which the detection pen 205 applies pressure to the resistance films 195 and 196. When pressure is applied from the detection pen in this manner, the resistance films 195 and 196 are formed. Are in contact. Also the detection pen 2
The portion to which pressure is applied from 05 is the counter electrode 207, the resistance between the conductive layer 197 and the counter electrode 207 is R15 as shown in FIG. 28 (c), and the resistance between the conductive layer 198 and the counter electrode 207 is Is R16, and the resistance between 200 and the detection pen 205 is R20. Although there is a certain sheet resistance in the resistance films of 195 and 196, this sheet resistance is so small that it can be ignored in the conductive layers 197, 198, 199 and 200.

FIG. 29 shows the configuration of the impedance converter 202. Reference numerals 208 and 209 in FIG. 29 are operational amplifiers, which are used as so-called voltage followers, and perform impedance conversion of an input signal and output it.

FIG. 30 shows the control of SW1 to SW4. C
When NT1 is at High level, SW1 and SW2 are in the ON state, and when CNT1 is at Low level, SW1 and SW2.
2 is in the off state. When CNT2 is at the high level, SW3 and SW4 are in the on state, and when CNT2 is at the low level, SW3 and SW4 are in the off state. CN
Both T1 and CNT2 are always driven in opposite phase.

FIG. 31 shows an equivalent circuit in the case of FIG. 28 (c). In FIG. 31A, CNT1 = High, CNT2 =
The equivalent circuit in the case of Low is shown, in which no voltage is applied to the conductive layers 199 and 6 and 0V is applied to the conductive layer 197 and 5V is applied to 198. Therefore, the voltage of 6 becomes (5 × R15) / (R15 + R16), so X ′
= (5 × R15) / (R15 + R16). That is, the position 14 of the detection pen in the X direction was detected as the analog signal X ′.

FIG. 31B shows CNT1 = Low, CNT.
2 shows an equivalent circuit in the case of 2 = High, and the conductive layer 1
No voltage is applied to 97 and the conductive layer 198, and 0 V is applied to the conductive layer 199 and 5 V is applied to 6. Therefore, since the voltage of 200 is 5V, X '= 5V. In this embodiment, when X '= 5V, this is not treated as an analog signal indicating the position of the pen in the X direction.

FIG. 32 shows an equivalent circuit diagram in the case of FIG. 28 (c). FIG. 32A shows CNT1 = High, CNT2.
= Low, the equivalent circuit is shown, and the conductive layer 199
No voltage is applied to 6 and 6 and 0 V is applied to the conductive layer 197.
Is applied to 198 at 5V. Therefore, 198
Is 5V, and Y '= 5V. In this embodiment, when Y '= 5V, this is not treated as an analog signal indicating the position of the pen in the Y direction.

FIG. 32B shows CNT1 = Low, CNT.
2 shows an equivalent circuit in the case of 2 = High, and the conductive layer 1
No voltage is applied to 97 and the conductive layer 198, and 0 V is applied to the conductive layer 199 and 5 V is applied to the conductive layer 200. Therefore, the voltage of 6 becomes 5V, and Y '=
It is (5 × R19) / (R19 + R20). That is,
The position 14 of the detecting pen in the Y direction was detected as an analog signal Y '.

The display device illustrated in FIG. 27 detects the position of the pen as described above. That is, CNT1 = High
When h and CNT2 = Low, the position of the detection pen in the X direction is detected as an analog signal, while CNT196 =
When High and CNT1 = Low, the position of the detection pen in the Y direction is detected as an analog signal. Then, the obtained analog signal is converted into digital signals DX and DY by the A / D converter 203. Digital signals DX, D
Convert to Y. The digital signals DX and DY are output to the pen speed detecting unit 170, the vector change detecting unit 171, and the correcting unit 172 of FIG. 27 and are corrected.

Position detection may be performed in the liquid crystal display device of the present invention by the configuration and method described in this example.

[0162]

As described above, according to the liquid crystal display device of the present invention, the problems of double image, parallax shift and the like in image quality deterioration, and thickness / weight increase are increased, and the manufacturing cost is increased. Instead, a position detection function can be added to a display device such as a liquid crystal display device. Therefore, according to the present invention, it is possible to provide a light and thin liquid crystal display device with a coordinate input function, which has high image quality and low power consumption. Further, by applying the display device of the present invention to, for example, a portable information terminal, it is possible to provide a display device with a built-in position detection function, which has high portability, good display quality, and high input accuracy.

[Brief description of drawings]

FIG. 1 is a diagram schematically showing an example of a sectional structure of a liquid crystal display device of the present invention.

FIG. 2 is a diagram schematically showing an example of a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 3 is a diagram schematically showing an example of a sectional structure of a liquid crystal display device of the present invention.

FIG. 4 is a diagram schematically showing an example of a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 5 is a diagram schematically showing an example of a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 6 is a diagram schematically showing an example of a sectional structure of a liquid crystal display device of the present invention.

FIG. 7 is a diagram schematically showing an example of a cross-sectional structure of a liquid crystal display device of the present invention.

FIG. 8 is a diagram schematically showing another example of the configuration of the liquid crystal display device of the present invention.

FIG. 9 is a diagram for explaining the relationship between a liquid crystal cell and a resistance film.

FIG. 10 is a diagram schematically showing an example of a pattern of a resistance film included in the liquid crystal display device of the present invention.

FIG. 11 is a diagram schematically showing an example of a pattern of a resistive film included in the liquid crystal display device of the present invention.

FIG. 12 is a diagram for explaining an example of a coordinate calculation method when the pressure detection element is made of a piezoelectric material.

FIG. 13 is a diagram for explaining an example of a coordinate calculation method when the pressure detection element is made of a pressure sensitive body.

FIG. 14 is an equivalent circuit when a bias potential VB is set by using a surface division type.

FIG. 15 is an equivalent circuit when a pressure sensitive body or a piezoelectric gate thin film transistor is used as a pressure detection element.

FIG. 16 is an equivalent circuit in which the pressure detection element is made of a piezoelectric material, a surface-divided type is used, and the opposing surface is floating.

FIG. 17 is an equivalent circuit when the pressure detecting element is made of a piezoelectric material and a double-sided split type is used.

FIG. 18 is an equivalent circuit when a pressure sensitive element or a piezoelectric gate thin film transistor is used as a pressure detection element and a double-sided split type is used. .

FIG. 19 is an equivalent circuit (surface division type) when a piezoelectric gate thin film transistor is used as a pressure detection element.

FIG. 20 is an equivalent circuit (double-sided split type) when a piezoelectric gate thin film transistor is used as a pressure detection element.

FIG. 21 is a diagram showing an example of the configuration of a coordinate detection circuit when a piezoelectric body is used.

FIG. 22 is a diagram showing an example of a configuration of a coordinate detection circuit when a thin film transistor in which a pressure sensitive body is connected to a gate is used.

FIG. 23 is a diagram showing an example of the configuration of a coordinate detection circuit when a piezoelectric body is used.

FIG. 24 is a diagram showing an example of a configuration of a coordinate detection circuit when a thin film transistor in which a pressure sensitive body is connected to a gate is used.

FIG. 25 is a diagram showing an example of the configuration of a coordinate detection circuit when a piezoelectric body is used.

FIG. 26 is a diagram showing an example of the configuration of a coordinate detection circuit when a pressure sensitive body or a piezoelectric gate thin film transistor is used as a pressure detection element.

FIG. 27 is a diagram showing an example of a configuration of a display device having a pen input function.

FIG. 28 is a diagram for explaining the principle of the pen coordinate detection device.

FIG. 29 is a diagram for explaining an example of the impedance configuration.

FIG. 30 is a diagram for explaining control of SW1 to SW4.

FIG. 31 is an equivalent circuit corresponding to FIG.

FIG. 32 is an equivalent circuit corresponding to FIG.

FIG. 33 is an equivalent circuit corresponding to FIG.

[Explanation of symbols]

11 ... Array substrate 12 ... Counter substrate 13 ......... Liquid crystal layer 14 ... Spacer 15 ... Insulating substrate 16 ... Pixel electrode 17 ......... Thin film transistor 17g ......... gate electrode 17s ... Source electrode 17d ......... Drain electrode 17i ......... Semiconductor film 18: Gate insulating film 19 ......... Passivation film 21 ... Insulating substrate 22 ………… Resistive film 23 ......... Piezoelectric body 24 ………… Color filter 25 ………… Common electrode 26 ... Bias electrode 31 ………… Black matrix 40 ………… MIM 50 ………… Pressure-sensitive gate thin film transistor

Continuation of front page (56) Reference JP-A-9-127521 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) G02F 1/1333 G02F 1/133 540 G09G 3/36 G06F 3/033 350 A G09F 9/00 366 G

Claims (4)

(57) [Claims] 1. A first substrate on which a first electrode is disposed, a second substrate on which a second electrode is disposed, and between the first substrate and the second substrate. Columnar spacers arranged in a matrix, a liquid crystal layer sandwiched in a gap between the first substrate and the second substrate held by the spacer, the first electrode or the second substrate Means for applying a display signal voltage to the electrode, between the first substrate and the spacer, or the second
Substrate and the disposed pressure sensing element between the spacers, when the pressure is applied to the pressure sensing element, on the basis of an output signal of the pressure detecting element <br/> element, the pressure the pressure is applied a liquid crystal display device characterized by including a means for detecting the position of the detection <br/> element. 2. The liquid crystal display device according to claim 1, wherein at least a part of the spacer is made of a piezoelectric material. Wherein further comprising a disposed a resistor film to be in contact with the pressure sensing element, according to claim 1 wherein the output signal of the pressure sensing element, characterized in that it is detected via the resistor film The liquid crystal display device according to item 1. 4. A first substrate, a second substrate, columnar spacers arranged in a matrix between the first substrate and the second substrate, and the first substrate . Between the spacers or the second
Substrate and the disposed pressure sensing element between the spacers, when the pressure is applied to the pressure sensing element, on the basis of an output signal of the pressure detecting element <br/> element, the pressure the pressure is applied position detecting device being characterized in that and means for detecting the position of the detection <br/> element.