JPH07182109A - Tablet device unified with display - Google Patents

Abstract

PURPOSE:To attain a coordinate detecting function by means of a pen which requires no connection cable. CONSTITUTION:This tablet device is provided with a pen 12 which points an optional position on an LCD panel 10 and transmits an AC signal, the LCD drive circuits 18 and 22 which apply the voltage to the electrodes to display data in a display period, and the selection circuits 20 and 24 which successively switch and input the signals received from each electrode that detects the AC signal sent from the pen 12 via the coupling capacity secured between the electrode and the pen 12 in a coordinate detecting period. Furthermore the switch circuits 14 and 16 are added to connect the electrodes to the circuits 18 and 22 or the circuits 20 and 24 according to the switching timing set between the display period and the coordinate detecting period, together with the signal receiving circuits 26 and 28 which detect the coordinate positions pointed by the pen 12 based on the signal value given from the circuits 20 and 24 and detected by the electrodes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display-integrated type tablet device suitable for various information processing devices such as an electronic notebook, a pen input word processor, a pen input personal computer and a pen input terminal.

[0002]

2. Description of the Related Art An integrated input display device in which a tablet, which is a coordinate input device, and a display device are superposed on each other has begun to be used as a display input device of an information processing device. The integrated input / display device is excellent in operability because the input position (coordinates) of information and the display position coincide with each other.

Integrated input and display devices are typically LCDs.
It is realized by superimposing a transparent tablet (a coordinate input device using a pen as a position indicating means) on the display surface of the (liquid crystal display) or laying an opaque tablet under the LCD. That is, in the usual configuration, a tablet is required in addition to the LCD.

On the other hand, if the tablet function can be realized by using the electrodes of the dot matrix LCD as they are, a dedicated tablet becomes unnecessary, so that the increase in cost can be suppressed considerably, and it is effective in reducing the weight of the device. .
With such a configuration, there is a great merit in the application of pen input in a word processor or the like.

Such a display-integrated tablet device using the electrodes of the LCD for coordinate detection is conventionally realized by operating according to a timing chart as shown in FIG.

When performing coordinate detection using the electrodes of the LCD, the operation time of one frame period (for example, 17 ms) of the LCD is set to the display period and the coordinate detection period (for example, 800 μs).
In the display period, the same operation as that of a general LCD is performed, and in the coordinate detection period, a coordinate detection voltage is sequentially applied to the vertical and horizontal electrodes of the LCD, and the voltage is applied between the pen and the electrode. And the X and Y coordinates are measured.

In the coordinate detection period, first, L shown in FIG.
A voltage is sequentially applied to the vertical electrodes (for X coordinate measurement) of the CD (X measurement period). When the pen is used to press on the coordinate detection surface (display screen), when a voltage is applied to the lateral electrode immediately below the pen tip, as shown in FIG. Depending on the capacity, the pen tip sensor (metal rod)
A pulse voltage is generated as shown in FIG. By measuring the time (Tx) from the start of X-coordinate measurement to the detection of this pulsed voltage, the X-coordinate of the pen tip corresponding to Tx can be detected.

Subsequently, the Y coordinate is similarly measured (Y
During the measurement period), the time (Ty) from the start of Y coordinate measurement to the detection of the pulsed voltage is measured to detect the Y coordinate of the pen tip according to Ty. In this way, one point (X coordinate, Y coordinate) on the coordinate detection surface designated by the pen is obtained.

Even if one frame period is divided into the display period and the coordinate detection period as described above, the pulse width of the voltage applied to the electrode during the coordinate detection period is short, so that the voltage is applied to the electrode during the coordinate detection period. Has almost no effect on the display.

The signal detected by the pen is processed through the circuit shown in FIG. The potential of the voltage detected by the pen is first amplified by an amplifier provided inside the pen. The signal output from the pen is processed by the analog processing circuit on the LCD.
The potential detected from the upper electrode and the lower electrode is divided according to the voltage application timing of the electrodes and further amplified by an amplifier having a magnification suitable for each output level. Then, it is filtered by a low-pass filter (LPF), and it is detected by the comparator circuit whether or not it becomes larger than the threshold level, and a pulse is generated. The coordinates of the pen tip can be known by measuring the time until the pulsed voltage is detected.

Generally, the display-integrated type tablet device realizes an electrostatic coupling type coordinate detection function (tablet) in which LCD electrodes are sequentially applied during a coordinate detection period and a coordinate position signal is detected by a pen.

The structure of the pen used in this electrostatic coupling system is shown in FIG. On the coordinate detection surface (LC
The detection axis 2 for detecting the voltage by pointing the position on the D panel, the pen tip switch 4 for detecting that the detection axis 2 is pressed against the LCD panel, and the voltage signal detected via the detection axis 2. An amplifier 6 that amplifies is provided.

The pen tip switch information from the pen tip switch 4 and the detection signal that has passed through the amplifier 6 are output to the tablet control device via the connection cable 8. The tablet control device determines the coordinate position designated by the detection axis based on the output signal from the pen.

As described above, since the pen used in the electrostatic coupling system needs to output the voltage detection signal and the pen tip switch information to the tablet control device, the connection cable 8 is indispensable.

[0015]

As described above, in the conventional display-integrated type tablet device, the pen used for pointing is connected through the connection cable 8. For this reason, there are problems in that the operation of the user is hindered, and a storage space for the connection cable is required, which makes it inconvenient to carry.

The present invention has been made in view of the above points, and provides a display-integrated tablet device capable of realizing a coordinate detection function using display electrodes by using a pen that does not require a connection cable. The purpose is to

[0017]

The present invention provides a display-integrated tablet device having a panel having a plurality of electrodes arranged in different directions so as to intersect with each other.
The position indicating means for indicating an arbitrary position on the panel is transmitted from the position indicating means via the position indicating means for transmitting an AC signal and the coupling capacitance between the position indicating means and the electrodes. Electrode scanning means for sequentially switching and inputting signals from each electrode for detecting an AC signal, and the panel instructed by the position instructing means on the basis of the signals detected by each electrode input by the electrode scanning means It is characterized by comprising coordinate detection means for detecting the upper coordinate position.

Further, according to the present invention, in order to drive the pixels arranged in a matrix to display data, a plurality of electrodes arranged corresponding to each pixel and arranged in different directions so as to intersect with each other are provided. In a display-integrated type tablet device which has a panel provided and which performs display and coordinate detection by providing a display period and a coordinate detection period, it is for indicating an arbitrary position on the panel, and an AC signal Position indicating means for transmitting, and electrode driving means for applying a voltage to a predetermined electrode in order to display data during the display period,
An electrode scanning means for sequentially switching and inputting a signal from each electrode for detecting an AC signal transmitted from the position indicating means via a coupling capacitance between the position indicating means and the electrodes during the coordinate detection period; The connection switching means connects the electrode to the electrode driving means or the electrode scanning means in accordance with the timing of switching between the display period and the coordinate detection period, and input by the electrode scanning means during the coordinate detection period. Coordinate detecting means for detecting the coordinate position on the panel indicated by the position indicating means based on the signal value detected by each electrode.

[0019]

According to this structure, the AC signal transmitted from the position indicating means (pen) is detected on the electrode side provided on the panel through the coupling capacitance between the position indicating means and the electrode. It During the coordinate detection period, the panel surface is scanned by sequentially switching and inputting the signal detected by each electrode to each electrode. Then, the value of the coordinate pointed by the position pointing means is determined based on the value of the signal detected by each electrode, for example, at the timing when the value exceeds a predetermined value.

By providing a display period and a coordinate detection period and having two functions of driving one electrode for data display and detecting a signal by the coupling capacitance, the coordinate detection on the position indicating means side is performed. The operation (signal detection) becomes unnecessary.

[0021]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a display-integrated tablet device according to this embodiment. As shown in Figure 1,
The display-integrated tablet device includes an LCD panel 10, a pen 12, a horizontal electrode switch circuit 14, a vertical electrode switch circuit 16, a horizontal electrode LCD drive circuit 18, a horizontal electrode select circuit 20, and a vertical electrode LCD drive circuit 22. The vertical electrode selection circuit 24, the horizontal electrode signal receiving circuit 26, the vertical electrode signal receiving circuit 28, the tablet control device 30, and the display control device 32.

The display-integrated type tablet device is connected to the information processing device 40 and operates by providing a display period and a coordinate detection period, and is used for displaying processing contents by the information processing device 40 and for data input. To be

The LCD panel 10 is a panel for displaying and inputting coordinate data. In this embodiment, the horizontal electrodes that are the Y-coordinate detection electrodes and the vertical electrodes that are the X-coordinate detection electrodes are arranged in different directions (vertical and horizontal) so as to intersect with each other.

The pen 12 touches the LCD panel 10 with the pen tip (transmitting shaft 12a) during the coordinate detection period for detecting the coordinates, thereby causing the LCD panel 10 to move.
The position pointing device is used to send an AC signal (radio wave) to the electrodes disposed in the position to point the position. Figure 2
The structure of the pen 12 is shown in FIG. As shown in FIG. 2, the pen 12 is provided with a transmission shaft 12a, a pen tip switch 12b, an oscillation circuit 12c, a crystal oscillator 12d, and a power supply 12e.

The transmitting shaft 12a is a portion used for indicating a position on the LCD panel 10, and is an oscillating circuit 12c.
The AC signal generated by is transmitted. Pen tip switch 12
The switch b detects (switches on) that the transmission shaft 12a is pressed against the LCD panel 10, and notifies the oscillation circuit 12c of the detection state. The oscillator circuit 12c is
The pen tip switch 12b interlocks with the notification (when the switch is turned on) and oscillates an AC signal of a specific frequency. The crystal oscillator 12d generates a vibration that is a basis of a signal oscillated by the oscillator circuit 12c. The power supply 12e supplies electric power for oscillating an AC signal in the oscillation circuit 12c.

Under the control of the tablet control device 30, the horizontal electrode switch circuit 14 has LCD electrodes (horizontal electrodes) arranged on the LCD panel 10 and horizontal electrodes under the control of the display period or the coordinate detection period. The connection with the LCD drive circuit 18 or the horizontal electrode select circuit 20 is switched. FIG. 3 shows the configuration of the horizontal electrode switch circuit 14.

Under the control of the tablet control device 30, the vertical electrode switch circuit 16 includes an LCD electrode (vertical electrode) arranged on the LCD panel 10 and a vertical electrode according to the display period or the coordinate detection period. Connection switching with the LCD drive circuit 22 or the vertical electrode select circuit 24. The vertical electrode switch circuit 16 also has the same configuration as the horizontal electrode switch circuit 14 as shown in FIG.

Under the control of the display control circuit 30, the horizontal electrode LCD drive circuit 18 drives the LCD electrodes arranged in the horizontal direction on the LCD panel 10 during the display period, and L
The data is displayed on the CD panel 10.

The horizontal electrode select circuit 20 scans the LCD electrodes (horizontal electrodes) of the LCD panel 10 via the horizontal electrode switch circuit 14 during the coordinate detection period, and detects the coordinates by the AC signal from the pen 12. A signal is input and output to the horizontal electrode signal receiving circuit 26. FIG. 4 shows the configuration of the horizontal electrode select circuit 20.

Under the control of the display control circuit 30, the vertical electrode LCD drive circuit 22 drives the LCD electrodes arranged in the vertical direction on the LCD panel 10 during the display period to set L
The data is displayed on the CD panel 10.

The vertical electrode select circuit 24 scans the LCD electrodes (vertical electrodes) of the LCD panel 10 via the vertical electrode switch circuit 16 during the coordinate detection period, and receives an AC signal transmitted from the pen 12 in response to the scanning. The coordinate detection signal obtained is input and output to the vertical electrode signal receiving circuit 28. As shown in FIG. 4, the vertical electrode select circuit 24 has the same configuration as the horizontal electrode select circuit 20.

The horizontal electrode signal receiving circuit 26 receives the coordinate detection signal output from the horizontal electrode selecting circuit 20, performs signal processing, and outputs the signal to the tablet controller 30. The configuration of the horizontal electrode signal receiving circuit 26 is shown in FIG. As shown in FIG. 5, an amplifier 16a for amplifying a signal, a bandpass filter 26b for extracting a signal of a specific transmission frequency from the amplified signal, and a lowpass filter 26c for removing the transmission frequency to smooth the signal are provided. It is configured.

The vertical electrode signal receiving circuit 28 receives the coordinate detection signal output from the vertical electrode selecting circuit 24 and outputs it to the tablet controller 30. As shown in FIG. 5, the vertical electrode signal receiving circuit 28 has the same configuration as the horizontal electrode signal receiving circuit 26.

Under the control of the information processing device 40, the tablet control circuit 30 controls switching of the horizontal electrode switch circuit 14 and the vertical electrode switch circuit 16 according to the display period or the coordinate detection period, and Based on the coordinate detection signals from the horizontal electrode signal receiving circuit 26 and the vertical electrode signal receiving circuit 28, processing such as determination of X and Y coordinate values is performed.

The display control device 32 reads the display data under the control of the information processing device 40, and the LCD panel 1
In order to display data at 0, a coordinate display signal for driving the electrodes is sent to the horizontal electrode LCD drive circuit 18 and the vertical electrode LCD drive circuit 22 to perform display control.

The information processing device 40 controls the display-integrated type tablet device, sends the display data indicating the content to be displayed on the LCD panel 10 to the display control device 32, and operates the pen 12 from the tablet control device 30. Input the data of the designated coordinates.

Next, the operation of the first embodiment of the present invention will be described. Normally, in the display-integrated type tablet device, as shown in FIG. 6A, a display period and a coordinate detection period are provided in the operation time of one frame period, and the display operation and the coordinate detection operation are performed in each period. To execute.

The tablet control device 30 switches between the horizontal electrode switch circuit 14 and the vertical electrode switch circuit 16 in accordance with the timing of switching between the display period and the coordinate detection period. That is, the horizontal electrode switch circuit 14 and the vertical electrode switch circuit 16 are switched to the horizontal electrode LCD drive circuit 18 and the vertical electrode LCD drive circuit 22 during the display period to connect to the LCD electrodes, and coordinate During the detection period, the electrodes are switched to the side of the horizontal electrode select circuit 20 and the vertical electrode select circuit 24 (however, depending on the X coordinate detection period and the Y coordinate detection period) and connected to the LCD electrode.

The display operation is performed by sending display data from the information processing device 40 to the display control device 32. The display control device 32 performs signal processing for displaying an image on the LCD panel 10 and sends display data to the horizontal electrode LCD drive circuit 18 and the vertical electrode LCD drive circuit 22 to drive predetermined LCD electrodes. To be displayed on the screen.

The coordinate detection operation is performed during the coordinate detection period as shown in FIG.
As shown in (b) and (c), the horizontal electrode switch circuit 14 and the vertical electrode switch circuit 16 are respectively connected to the horizontal electrode select circuit 20 and the vertical electrode according to the timing of the X coordinate detection period or the Y coordinate detection period. This is executed by switching to the electrode select circuit 24 side.

Now, with the pen 12, the LCD panel 1
When 0 is instructed, the AC signal transmitted from the pen tip is detected on the LCD electrode side via the capacitance between the LCD electrode and the pen tip as shown in FIG.

That is, the pen tip of the pen 12 (transmitting shaft 12
When a) is pressed by the LCD panel 10, the switch of the pen tip switch 12b is turned on, and in response to this, an alternating signal is transmitted from the oscillation circuit 12c. This AC signal is
The crystal oscillator 12d provides a signal having a specific frequency determined in advance.

During the coordinate detection period, the horizontal electrode switch circuit 1
4 and the vertical electrode switch circuit 16 connects the vertical and horizontal electrodes of the LCD electrode to the horizontal electrode select circuit 20 and the vertical electrode select circuit 24. In the X coordinate detection period, the horizontal electrode select circuit 20 sequentially scans the X coordinate detection electrodes (horizontal electrodes), and similarly, in the Y coordinate detection period, the vertical electrode select circuit 24 causes the Y coordinate detection electrodes (vertical electrodes). Are sequentially scanned.

As shown in FIGS. 6 (d) and 6 (e), in each of the X coordinate detection period and the Y coordinate detection period, the select circuits 20 and 24 scan the next LCD electrode at the rising edge of the timing chart. Move the target.

The transmission axis 12a of the pen 12 is the LCD panel 1
Since the AC signal is transmitted when it is pressed to 0,
Each switch circuit 14, 16, each select circuit 20, 24
Signals detected by each LCD electrode are sent to the horizontal electrode signal receiving circuit 26 and the vertical electrode receiving circuit 28 via the.

For example, the X coordinate detection electrode (horizontal electrode) is 6
When there are 40 lines, the horizontal electrode select circuit 20 scans each electrode, and the horizontal signal reception circuit 26 outputs a signal detected at 640 times when each electrode is turned on (connected). Are sequentially sent to. Similarly, when there are 400 Y coordinate detection electrodes (vertical electrodes), the signals detected at the timing of 400 times are sequentially sent to the vertical signal receiving circuit 28.

Each of the signal receiving circuits 26 and 28 amplifies the received signal with the amplifiers 26a and 28a, and passes the band pass filters 26b and 28b, so that the AC signal transmitted from the pen 12 is detected from each electrode. You can get a signal. The signal after passing through the band pulse filter 26b in the horizontal electrode signal receiving circuit 26 is shown in FIG.

Further, the low pass filters 26c and 28c
To pass the band pulse filter 26b
The signal after passing through is smoothed. The signal after passing through the low pass filter 26c in the horizontal electrode signal receiving circuit 26 is shown in FIG. 8 (b).

That is, the signals output from the horizontal electrode signal receiving circuit 26 and the vertical electrode receiving circuit 28 are obtained by detecting the voltage applied to the electrodes on the pen side in the electrostatic coupling method as shown in FIG. The signal is the same as the signal sent to the tablet controller, which is obtained by scanning the electrodes in each direction.

In the tablet control device 30, the signals output from the signal receiving circuits 26 and 28 exceed the preset threshold level from the time elapsed during each of the X coordinate detection period and the Y coordinate detection period. Counting time (timing) (tx in FIG. 8B)
). The tablet control device 30 determines the X coordinate value and the Y coordinate value based on the count values corresponding to the scanning timings of the select circuits 20 and 24, and outputs them to the information processing device 40.

Next, the operation of the second embodiment will be described. In the above-described first embodiment, as shown in FIGS. 6B and 6C, the X coordinate detection period and the Y coordinate detection period are provided during the coordinate detection period, and the X coordinate and the Y coordinate It is detecting. In the second embodiment, as shown in FIG. 9, X coordinate detection and Y coordinate detection are performed in parallel.

As shown in FIGS. 9B and 9C, there is a period in which the X coordinate detection period and the Y coordinate detection period overlap. Figure 9
In the example shown in, the Y coordinate detection period is shorter because the number of Y coordinate detection electrodes is smaller than that of the X coordinate detection electrodes. For example, if the number of vertical electrodes and horizontal electrodes is the same, The coordinate detection periods are exactly the same.

Similar to the first embodiment, the horizontal electrode switch circuit 14 and the vertical electrode switch circuit 16 are switched to the horizontal electrode LCD drive circuit 18 and the vertical electrode LCD drive circuit 22 during the display period. During the coordinate detection period, it is switched to the horizontal electrode select circuit 20 and the vertical electrode select circuit 24, respectively.

The circuit for detecting the X coordinate and the circuit for detecting the Y coordinate are independent as shown in FIG.
The above-described scanning is possible in the embodiment. The horizontal electrode signal receiving circuit 26 and the vertical electrode signal receiving circuit 28 process the received signals and output them to the tablet controller 30. The tablet control device 30 includes the horizontal electrode signal receiving circuit 2
6 and the vertical electrode signal receiving circuit 28 based on the respective signals, the X coordinate value and the Y coordinate value are determined, and the information processing device 4
Output to 0.

Thus, in the coordinate detection period,
The LCD panel 10 receives the AC signal transmitted from the pen 12.
Is detected by the LCD electrodes arranged in the air via a capacitance such as air, and each electrode is scanned by the horizontal electrode select circuit 20 and the vertical electrode select circuit 24, respectively, and the signal detected by each electrode (see FIG. By smoothing a)), the scanning signal (FIG. 8B) for obtaining the coordinates designated by the pen 12 can be obtained.

That is, unlike the conventional tablet device using the electrostatic coupling method, it is not a method of detecting the voltage applied to the electrodes on the pen side, and therefore a connection cord for connecting the pen and the main body is not required. Therefore, the operability and portability of the pen are improved.

Further, as in the second embodiment, the X coordinate detection period and the Y coordinate detection period can be provided in parallel, so that the X coordinate detection period and the Y coordinate detection period are consecutively provided. Compared with the above, since the coordinate detection period is short, it is possible to avoid the influence on the display period in one frame period even if the number of electrodes increases.

In the above embodiment, the example of the coordinate detection operation is shown by using the LCD, but the same operation can be performed by a dot matrix display such as an EL display (ElectroLuminescent display). It is also possible to apply the present invention to a tablet device dedicated to coordinate detection that does not serve as a display device.

[0059]

As described above, according to the present invention, the signal transmitted from the pen is detected on the electrode side, and the coordinates of the position designated by the pen are determined from the signal detected by each electrode. The coordinate detection function using the display electrodes can be realized by using a pen that does not require a connection cable.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a display-integrated tablet device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing the configuration of a pen 12 in this embodiment.

FIG. 3 is a lateral electrode switch circuit 14 according to the present embodiment.
The figure which shows the structure of (vertical electrode switch circuit 16).

FIG. 4 is a horizontal electrode select circuit 20 according to the present embodiment.
The figure which shows the structure of (vertical electrode selection circuit 24).

FIG. 5 is a diagram showing a configuration of a horizontal electrode signal receiving circuit 26 (vertical electrode signal receiving circuit 28) in the present embodiment.

FIG. 6 is a timing chart showing operation timings in the first embodiment of the present invention.

FIG. 7 is a diagram for explaining potential detection by LCD electrodes in the present embodiment.

FIG. 8 is a diagram for explaining signal processing of the horizontal electrode signal receiving circuit 26 (vertical electrode signal receiving circuit 28) in the present embodiment.

FIG. 9 is a timing chart showing the operation timing in the second embodiment of the present invention.

FIG. 10 is a timing chart showing an operation timing in which a display period and a coordinate detection period of the conventional display-integrated tablet device are provided.

FIG. 11 is a diagram showing electrodes arranged on an LCD.

FIG. 12 is a diagram for explaining potential detection by a pen.

FIG. 13 is a diagram showing an analog processing circuit for processing a signal detected by a pen.

FIG. 14 is a block diagram showing a configuration of a pen used in a conventional electrostatic coupling system.

[Explanation of reference numerals] 10 ... LCD panel, 12 ... Pen, 14 ... Horizontal electrode switch circuit, 16 ... Vertical electrode switch circuit, 18 ... Horizontal electrode LCD drive circuit, 20 ... Horizontal electrode select circuit,
22 ... Vertical electrode LCD drive circuit, 24 ... Vertical electrode select circuit, 26 ... Horizontal electrode signal receiving circuit, 28 ... Vertical electrode signal receiving circuit, 30 ... Tablet control device, 32 ... Display control device, 40 ... Information processing device .

Claims (6)

[Claims] 1. To drive pixels arranged in a matrix to display data, a plurality of electrodes are provided corresponding to each pixel and arranged in different directions so as to intersect with each other. In a display-integrated tablet device having a display panel and performing a coordinate detection together with a display period and a coordinate detection period, voltage application to a predetermined electrode for displaying data during the display period, and the coordinate Switching between the input of the signal detected via capacitive coupling at each electrode during the period,
A display-integrated type tablet device comprising control means for realizing different functions for the same electrode. 2. A display-integrated tablet device having a panel having a plurality of electrodes arranged in different directions so as to intersect with each other, for indicating an arbitrary position on the panel. A position indicating means for transmitting an alternating current signal and a signal from each electrode for detecting an alternating current signal transmitted from the position indicating means through the coupling capacitance between the position indicating means and the electrodes, and the signals are sequentially switched and input. Electrode scanning means, and coordinate detection means for detecting the coordinate position on the panel indicated by the position indicating means on the basis of the signal detected by each electrode input by the electrode scanning means. A display-integrated tablet device characterized in that 3. The display according to claim 2, wherein the electrode scanning means is provided in each direction in which the electrodes are arranged and inputs signals from the electrodes in each direction in parallel. Integrated tablet device. 4. In order to drive pixels arranged in a matrix to display data, a plurality of electrodes arranged corresponding to each pixel and arranged in different directions so as to intersect with each other are arranged. A display-integrated type tablet device having a panel and having a display period and a coordinate detection period to perform coordinate detection together with display, for transmitting an AC signal for indicating an arbitrary position on the panel. Position indicating means, an electrode driving means for applying a voltage to a predetermined electrode for displaying data during the display period, and a coupling capacitance between the position indicating means and the electrode during the coordinate detection period, Electrode scanning means for sequentially switching and inputting signals from each electrode for detecting an AC signal transmitted from the position indicating means, and timing for switching between the display period and the coordinate detection period. Then, based on the connection switching means for connecting the electrode to the electrode driving means or the electrode scanning means, and the signal value detected by each electrode input by the electrode scanning means during the coordinate detection period, A display-integrated tablet device comprising: coordinate detection means for detecting a coordinate position on the panel designated by the position designation means. 5. The electrode scanning means, the connection switching means, and the coordinate detecting means are provided for each direction in which the electrodes are arranged, and signals are input in parallel from the electrodes in each direction. The display-integrated type tablet device according to claim 4, wherein 6. The coordinate detecting means smoothes a signal detected from each successive electrode, compares the signal with a preset predetermined value, and based on the comparison result, in accordance with a signal generation timing. The display-integrated tablet device according to claim 2 or 4, wherein the coordinate position is detected.