JPH04195624A - Handwriting input display device - Google Patents

Abstract

PURPOSE:To improve the visibility of the display image of handwriting data with inexpensive constitution by sending the composite signal of the data signal of a detected position and a scanning signal for position detection which can be applied to plural electrodes to a liquid crystal display means and displaying it on the liquid crystal. CONSTITUTION:The scanning signal for position detection is applied to plural 1st electrodes of the LCD 21 by an X-directional driver 22x, a Y-directional driver 22y, and an MPU 29 and while the composite signal of the scanning signal for position detection and a scanning signal for liquid crystal driving is applied to plural 2nd electrodes of the LCD 21, a position where electrostatic capacity varies is detected through an electronic pen 23, an amplifying circuit 24, a detecting circuit 25, a counter 26 for coordinate detection, a coordinate detection controller 27, and a display controller 28. The composite signal of the data signal of this detected position and the scanning signal for position detection which can be applied to the 1st electrodes is sent out to the LCD 21 and displayed on the LCD. Consequently, a tablet which is used to input handwriting data is unnecessary and the visibility of the display image of the handwriting data can be improved with the simple constitution.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a handwriting input display device that detects and displays input handwritten data using a capacitance method.

[Prior art] Fig. 6 shows a tablet and L of a conventional handwriting input display device.
FIG. 2 is a perspective view showing a CD (liquid crystal display).

As shown in the figure, the conventional handwriting input display device includes a transparent tablet (coordinate input cover panel) 11 that detects the coordinates of the position where handwritten data is input, and a transparent tablet (coordinate input cover panel) 11 that is superimposed below the tablet 11, and a transparent tablet 11 that detects the coordinates of the position where handwritten data is input. and an LCDL 2 for displaying handwritten data input by the computer.

The electronic pen 13 is equipped with a capacitance detection circuit at its tip, and is configured to be able to detect handwritten data based on changes in capacitance on the tablet II.

FIG. 7 is an exploded perspective view showing the detailed structure of the tablet II shown in FIG. 6.

As shown in the figure, the tablet 11 is formed by sequentially overlapping a glass lla, a transparent insulator i1c, and a glass llb.

Gala X1. In la, a plurality of transparent electrodes 1 are formed parallel to each other at a predetermined pitch for detecting the X coordinate of the position of handwritten data.

A plurality of transparent electrodes 11Y for detecting the Y coordinate of the position of handwritten data are formed in parallel to each other at a predetermined pitch on the glass llb.

The glass lla and the glass llb are laminated with the transparent insulator 11c interposed so that the transparent electrode +11 and the transparent electrode 11y are perpendicular to each other.

FIG. 8 is a side sectional view showing the detailed structure of L CD +2 in FIG. 6. FIG.

As shown in the figure, the LCD 12 is connected to the polarizing plate 1 from above.
2a1 segment glass 12d1 segment transparent electrode 12b1 liquid crystal 12C, common transparent electrode 12e1 common glass 12 (, polarizing plate 12g, and reflection plate 12h are laminated in order).

Segment transparent electrode 121+ and common transparent electrode 12C
That's +1 transparent electrode for tablet 11! and transparent electrode+
Similar to ty, they are formed along the X direction and the Y direction, which are orthogonal to each other.

The liquid crystal 12c is sealed with a sealing material 121 between the segment transparent electrode 12b and the common transparent electrode 12e.

In the above configuration, when inputting handwritten data, a scanning voltage is sequentially applied to the transparent electrode 111 and the transparent electrode 11y of the tablet 11 at a frequency of, for example, several hundred H2.

In this state, when the tip (pen tip) of the electronic pen 13 is traced on the tablet 11, a change in capacitance is detected by the capacitance detection circuit of the electronic pen 13, and the change in capacitance is matched with the scanning timing, thereby determining the coordinates of the traced position. Data is detected.

These coordinate data are processed by a circuit not shown, and the segment transparent electrode +2b and the common transparent electrode 12e of the LCD 12 are driven according to the coordinate data, and the input handwritten data is displayed on the LCD 12 below the input position. displayed in the position.

[Problems to be Solved by the Invention] In the conventional handwriting input display device described above, the tablet 11 for detecting the position of handwritten data and the LCD 12 for displaying the handwritten data are stacked. There is a problem in that it is difficult to align the tablet 11 and the LCD 12, and the material cost and processing cost are high.

Furthermore, since the tablet 11 is placed above the LCD 12, there is a problem that the visibility of the displayed image of the input handwritten data on the LCD 2 is poor.

Therefore, the present invention provides a handwriting input display device that does not require alignment between the tablet 11 and the LCD 12 and can improve the visibility of the displayed image of handwritten data with an inexpensive configuration.

[Means for Solving the Problems] A matrix type liquid crystal display means including a plurality of first electrodes and a plurality of second electrodes respectively formed at predetermined intervals along the X direction and the Y direction; A scanning signal for position detection can be sequentially applied to the first electrode of the electrode, and a composite signal of a scanning signal for position detection and a scanning signal for driving the liquid crystal of the liquid crystal display means can be sequentially applied to the plurality of second electrodes. detecting a position where capacitance changes on the liquid crystal display means when a scanning signal and a composite signal for position detection are respectively applied to a plurality of first electrodes and a plurality of second electrodes; and a position detection means, and is configured to send a composite signal of the data signal of the detected position and a scanning signal for position detection that can be applied to the plurality of first electrodes to the liquid crystal display means for liquid crystal display. ing.

[A scanning signal for position detection is applied to the plurality of first electrodes of the liquid crystal display means by the action applying means, and a composite signal of the scanning signal for position detection and the scanning signal for driving the liquid crystal of the liquid crystal display means is applied. is being applied to the plurality of second electrodes of the liquid crystal display means, the position where the capacitance on the liquid crystal display means has changed is detected by the position detection means, and the data signal of this detected position and the plurality of first electrodes are detected by the position detection means. A composite signal with a scanning signal for position detection that can be applied to the electrodes is sent to the liquid crystal display means and displayed on the liquid crystal. Therefore, there is no need for the tablet that was conventionally placed above the liquid crystal display means and used for inputting handwritten data, so there is no need to align the tablet and LCD, and it is possible to write handwritten data with an inexpensive structure. The visibility of data display images can be improved.

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a schematic block diagram showing an embodiment of a handwriting input display device according to the present invention, FIG. 2 is a schematic block diagram of a handwriting input display device according to the present invention, and FIG. 3 is a diagram of an LCD (liquid crystal display). A side sectional view showing the detailed configuration and FIG.
FIG. 2 is an explanatory diagram of main parts showing a segment transparent electrode and a common transparent electrode of the LCD shown in the figure.

As shown in FIGS. 1 and 2, the handwriting input display device of the present invention includes an LCD 21, an electronic pen 23, and a control device 2.
Consists of 0. However, in this embodiment, the LCD
No tablet is stacked above 21.

The electronic pen 23 is connected to the LCD 21 via the control device 20, and a capacitance detection circuit (not shown) is built into the tip (pen tip) of the electronic pen 23.

The control device 20 includes an X direction driver 22I, a Y direction driver 22Y, an amplifier circuit 24, a detection circuit 25, a coordinate detection counter 26, a coordinate detection controller 27, a display controller 28, and an MPU (microprocessor) 2.
9 is provided.

The electronic pen 23 includes an amplifier circuit 24, a detection circuit 25, a coordinate detection counter 26, a coordinate detection controller 27, and an MPU.
29 and then the X direction driver 22! and the Y-direction driver 22y, respectively.

The coordinate detection controller 27 is connected to an X-direction driver 22I and a Y-direction driver 22y via a display controller 28 and an MPU 29, respectively.

The X direction driver 221 and the Y direction driver 22y are L
They are respectively connected to a segment transparent electrode and a common transparent electrode, which will be described later, of CD2+.

The LCD 21 is an embodiment of the liquid crystal display means of the present invention.

X direction driver 22K and Y direction driver 22Y and M
PU29 is one embodiment of the application means of the present invention. The electronic pen 23, the amplifier circuit 24, the detection circuit 25, the coordinate detection counter 26, the coordinate detection controller 27, and the display controller 28 are one embodiment of the position detection means of the present invention.

As shown in FIG. 3, the LCD 21 includes a polarizing plate 21a, a segment glass 21d, a segment transparent electrode 21b, a liquid crystal 21c, a common transparent electrode 21e, a common glass 211, a polarizing plate 21g, and a reflecting plate 21h, which are laminated in order from the top in the figure. It is made up of.

Liquid crystal 21. C is sealed with a sealing material 21i between the segment transparent electrode 21b and the common transparent electrode 21e.

Segment transparent electrode 21b and common transparent electrode 21e
is an example of the first electrode and second electrode of the present invention.

As shown in FIG. 4, the segment transparent electrodes 21b (illustrated x1, x2, and X3) and the common transparent electrode 21e (illustrated YL Y2 and Y3) of the LCD 21 are arranged along the each formed.

Note that the LCD 2+ shown in the figure is an example of an LCD having three display dots in each of the X direction and the Y direction.

X direction driver 22! is the segment transparent electrode 21b
The configuration is such that it is possible to apply a scanning signal for position detection to detect handwritten data to (Xl, x2, and X3).

The Y direction driver 22y has a common transparent electrode 21e (Y
1, Y2, and Y3), a composite signal is applied that is a combination of a scanning signal for driving the liquid crystal of the LCD 21, which will be described later, given from the display controller 28, and a scanning signal for position detection for detecting handwritten data. It is configured so that it can be done.

Next, the operation of the above embodiment will be explained.

FIG. 5 is a timing chart showing main signals in the circuit of the handwriting input display device of FIG.

As shown in the figure, the common transparent electrode 21e of LCD2+
(Yl, Y2, and Y3), for example, the polarity is reversed for each display dot on the LCD 2], and a scanning signal for driving the liquid crystal (upper row in the figure) is applied from the display controller 28 in the form of dividing the frame frequency of the LCD 21. ing.

When the position of input handwritten data is detected using a scanning signal for position detection (middle stage in the figure) having a frequency that is, for example, 12 times the frame frequency of the LCD 21, this scanning signal given from the coordinate detection controller 27 and the above-mentioned liquid crystal drive The scanning signal for
This composite signal (lower row in the figure) is applied to the common transparent electrode 21g.

A scanning signal for position detection for inspecting handwritten data is applied to the segment transparent electrode 21b of the LCD 21.

Here, the display response speed of the LCD 21 is, for example, 250 m5.
If the frequency of the scanning signal is 200Hz,
Scanning time is approximately 2. ．． 5no, and does not affect the display on LCD2+.

The X direction driver 2 is connected to the common transparent electrode 21e of the LCD 21.
2y, a composite signal in which a scanning signal for driving the liquid crystal and a scanning signal for position pressure detection are combined is sequentially applied to the segment transparent electrode 21b from the X-direction driver 22! While position detection signals are being sequentially applied from the electronic pen 2
When the tip of the pen 3 traces the LCD 21, the capacitance detection circuit of the electronic pen 23 detects a change in the capacitance on the LCD 21.

The signal detected by this capacitance detection circuit is transmitted to the amplifier circuit 2.
4 and then sent to the detection circuit 25.

This amplified signal is converted into a binary signal by the detection circuit 25 and sent to the coordinate detection counter 26.

The binarized signal is counted by the coordinate detection counter 26, and this count value is sent to the coordinate detection controller 27.

The coordinate detection controller 27 detects the coordinate data of the position traced by the tip of the electronic pen 23 from this count value.

The coordinate data of this position is sent to the internal RAM (Random Access Memory) of the display controller 28,
A pixel corresponding to this coordinate data is specified, and the display controller 28 determines whether the specified pixel is to be lit or not lit, and a display data signal based on this determination is output to the MPU 29. In the MPU 29, the display data signal and the scanning signal for position detection are combined and sent to the LCD 21, where a liquid crystal display is performed.

Therefore, since the tablet 11 as shown in the conventional example is not stacked on the LCD 2+, the tablet 1.1 and L
There is no need to perform alignment with the CDI 2, and the visibility of the displayed image of handwritten data can be improved with an inexpensive configuration.

Furthermore, even if a thin handwriting input display device is required to be highly portable, the handwriting input display device of this embodiment can easily meet the requirements.

In addition, in the above-mentioned embodiment, there are 3
Although the explanation has been given using an LCD having a display dot as an example, an LC having a plurality of display dots of 3 or more dots may also be used.
D may also be used.

[Effects of the Invention] As explained above, the present invention provides a matrix type liquid crystal that includes a plurality of first electrodes and a plurality of second electrodes formed at predetermined intervals along the X direction and the X direction. The display means can sequentially apply a scanning signal for position detection to the plurality of first electrodes, and the scanning signal for position detection and the scanning signal for driving the liquid crystal of the liquid crystal display means can be applied to the plurality of second electrodes. an application means capable of sequentially applying a composite signal, and a change in capacitance on a liquid crystal display means when a scanning signal for position detection and a composite signal are respectively applied to a plurality of first electrodes and a plurality of second electrodes; and a position detecting means for detecting the position detected, and sends a composite signal of the data signal of the detected position and a scanning signal for position detection pressure that can be applied to the plurality of first electrodes to the liquid crystal display means to display the liquid crystal display. Therefore, the visibility of the displayed image of handwritten data can be improved with an inexpensive configuration.

[Brief explanation of the drawing]

Fig. 1 is a schematic block diagram showing an embodiment of the handwriting input display device according to the present invention, Fig. 2 is a schematic block diagram of the handwriting input display device according to the present invention, and Fig. 3 shows the detailed structure of the LCD. 4 is a main part explanatory diagram showing the segment transparent electrodes and common transparent electrodes of the LCD shown in FIG. 1; FIG. 5 is a timing chart showing main signals in the circuit of the handwriting input display device shown in FIG. 1. , FIG. 6 is a perspective view showing the tablet and LCD of a conventional handwriting input display device, FIG. 7 is an exploded perspective view showing the detailed structure of the tablet in FIG. 6, and FIG. 8 is a detailed view of the LCD in FIG. 6. FIG. 20...Control device, 21...LC
D, 21b...Transparent electrode for segment, 21c
...Liquid crystal, 21e...Common transparent electrode, 22! ...X direction driver, 22y...
... Y direction driver, 23 ... Electronic pen, 24
......Amplification circuit, 25...Detection circuit, 2
6...Coordinate detection counter, 27...
Coordinate detection controller, 28...Display controller, 29...,...MPU0 Fig. 1 21/ Fig. 2 21c 21h Fig. 3 1b Fig. 4 Fig. 5

Claims (1)

[Claims] A matrix type liquid crystal display means including a plurality of first electrodes and a plurality of second electrodes formed at predetermined intervals along the X direction and the Y direction, and a position detection means for the plurality of first electrodes. an application means capable of sequentially applying a scanning signal for scanning, and sequentially applying a composite signal of a scanning signal for position detection and a scanning signal for driving the liquid crystal of the liquid crystal display means to the plurality of second electrodes; the plurality of first electrodes and the second
position detection means for detecting a position at which the capacitance on the liquid crystal display means changes when the scanning signal for position detection and the composite signal are respectively applied to the electrodes of the position detecting means; A handwriting input display device, characterized in that a composite signal of a data signal and a scanning signal for position detection that can be applied to the plurality of first electrodes is sent to the liquid crystal display means for liquid crystal display.