JP2001282442A - Coordinate reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize a coordinate reader to be easily carried and with satisfactory writing characteristics. SOLUTION: A writing sheet 20 of an electronic blackboard 1 is provided with a sheet main body 26 formed by a flexible material and a film 21 is stuck on its surface. Frame-like wire 22 formed by shape-memory alloy is embedded around the sheet main body 26 and frame-like heating wire 24 to be brought into contact with the wire 22 is embedded outside the wire 22. In addition, a loop-like coil 23X by which voltage is induced by an alternate magnetic field outputted from a coordinate input pen 60 is embedded inside the sheet main body 26 and inside the wire 22. And the wire 22 is transformed due to heat by the heating wire 24 and the writing sheet 20 becomes from a folded state to the shape of flatly extended.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coordinate reading device for reading the position coordinates of the coordinate input means based on a signal generated in a loop-shaped conductor laid on a sheet by an alternating magnetic field generated from the coordinate input means.

[0002]

2. Description of the Related Art Heretofore, there have been known coordinate reading devices in which a writing surface is a plate-like surface and a sheet-like writing surface. As a writing surface having a plate-like shape, for example, a type such as a whiteboard (registered trademark) which is attached to a floor stand and placed on the floor, or a wall-mounted type is known.
As a writing surface having a sheet shape, for example, a device provided with a winding device for winding a sheet is known (Japanese Patent Application Laid-Open No. 58-182792).

[0003]

However, a writing surface having a plate shape can be moved, but has a problem that it is not easy to carry because the writing board is plate-shaped and long. Further, when the writing surface is sheet-shaped, the sheet drawn from the winding device is warped or wavy, so that there is a problem that writing performance is poor.

Accordingly, the present invention has been made to solve the above-mentioned problems, and has as its object to realize a coordinate reading device which is easy to carry and has good writability.

[0005]

Means for Solving the Problems, Functions and Effects of the Invention
According to a first aspect of the present invention, there is provided a coordinate reading apparatus including a sheet on which a plurality of loop-shaped conductors for detecting a signal output from a coordinate input unit are provided. The sheet has a flexibility, a shape memory alloy is attached to a predetermined area around the sheet, and a technical means including a heating means for heating the shape memory alloy is used.

That is, since the sheet is flexible, it can be folded or rolled up, so that it is easy to carry. Further, a shape memory alloy is attached to a predetermined range around the sheet, and a heating means for heating the shape memory alloy is provided, so that when the sheet is manufactured, the sheet is flat and not warped or wavy. By storing the shape in the state in the shape memory alloy and heating the shape memory alloy by the heating means when the sheet is spread, the sheet can be flattened without warping or waving. it can. Therefore, the writing surface does not warp or wave during use, so that the writing performance can be improved.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a coordinate reading apparatus according to the present invention will be described below with reference to the drawings. In each of the embodiments described below, a so-called electronic blackboard that electrically reads handwritten characters, figures, and the like drawn on a writing surface will be described as an example of a coordinate reading device according to the present invention.

[Main Structure of Electronic Blackboard] First, the main structure of the electronic whiteboard according to this embodiment will be described with reference to the drawings. 1A is an external perspective view illustrating the main structure of an electronic blackboard, FIG. 1B is a cross-sectional view taken along the line AA of FIG. 1A, and FIG. It is explanatory drawing which expands and shows a part of left end of (B). FIG. 2A is an explanatory view showing a state in which the writing sheet 20 shown in FIG. 1A is folded, and FIG. 2B shows a shape of the writing sheet 20 shown in FIG. FIG. 2C is an explanatory view, and FIG.
It is explanatory drawing which shows the shape which the writing sheet 20 shown to (B) spreads completely. FIG. 3A is an explanatory diagram showing a state in which a personal computer (hereinafter abbreviated as a PC) and a printer are connected to the electronic whiteboard 1 shown in FIG. 1A, and FIG. FIG. 2 is an explanatory diagram showing an enlarged view of a remote controller 30 provided in the electronic blackboard 1 shown in FIG.

The electronic blackboard 1 includes a writing sheet 20 formed in a horizontally long substantially rectangular shape, a remote controller 30 for operating the electronic blackboard 1, and a coordinate input pen 60 for writing on the writing surface 21a of the writing sheet 20. The power supply unit 14 includes an eraser 40 for erasing a written locus and data indicating the locus. The writing sheet 20
A sheet body 26 formed of a flexible material is provided, and a film 21 is adhered to the surface of the sheet body 26. FIG.
As shown in (A), the writing sheet 20 is foldable. As shown in FIG. 1A, a frame-shaped wire 22 made of a shape memory alloy is embedded around the sheet body 26.
Outside the frame, a frame-shaped heating wire 24 in contact with the wire 22
Is embedded. A loop coil 23 </ b> X in which a voltage is induced by an alternating magnetic field output from the coordinate input pen 60 is embedded inside the sheet body 26 and inside the wire 22. Although FIG. 1B shows only a loop-shaped coil for detecting X coordinates (hereinafter abbreviated as X-loop) for convenience of the drawing, actually, the loop-shaped coil is shown in FIG. As shown in A), it is composed of an X coil and a loop-shaped coil for detecting a Y coordinate (hereinafter abbreviated as a Y loop).

A circuit board 50 having the electrical configuration shown in FIG. 6 is embedded in the right end of the seat body 26. A remote controller 30 is connected to the lower portion of the right end of the seat body 26 via a cable 31 via a connector 11, and a power supply unit 14 is connected via a cable 12 via a connector 10. As shown in FIG. 3A, a PC 100 can be connected to the right end of the sheet main body 26 by a connector 102 via a cable 101, and a printer 200 can be connected by a connector 202 via a cable 201. It has become. Then, the content written on the writing surface 21a is displayed on the monitor screen 1 of the PC 100.
00a or print paper 2
03 can be printed.

As shown in FIG. 3B, the remote control 30 has a page return button 32 for returning by one page each time the writing data stored in the RAM 59 (FIG. 6) is pressed.
A page forward button 33 that sends one page each time it is pressed,
An erase button 34 that erases one page each time it is pressed, a printer output button 35 that is pressed to output stored writing data to the printer 200, and a PC output that is pressed to output stored writing data to the PC 100 A button 36, a power button 37 pressed to start or stop the electronic blackboard 1, and a display unit 38 for displaying the operation contents of these buttons, the number of pages, the state of the electronic blackboard 1, and the like on a liquid crystal. In this embodiment, the sheet main body 26 is formed of a cloth such as a nonwoven fabric, and the right end on which the circuit board 50 and various connectors are provided has more rigidity than other parts. The wire 22 is formed of a nickel-titanium-based shape memory alloy, and the heating wire 24 is formed of nichrome. The transformation temperature of the nickel-titanium shape memory alloy is 10 ° C to 90 ° C.
Can be set in the range of 25 ° C., but is preferably set in the range of 25 ° C. to 90 ° C. so that transformation does not occur spontaneously at room temperature. Further, as the film 21, PET
(Polyethylene terephthalate) film is used.

[Structure of Loop Coil] Next, the structure of the loop coil will be described with reference to FIG. FIG.
4A is an explanatory view showing a configuration of a loop-shaped coil with a part thereof being omitted, and FIG. 4B is an explanatory view showing a width and an overlapping pitch of the loop-shaped coil shown in FIG. is there. As shown in FIG. 4A, a coordinate input pen 6 is provided in the X-axis direction.
X1 to X for detecting the X coordinate of the (X, Y) coordinate of 0
There are m m X loops 23X arranged in the Y-axis direction, and Y1-Yn Y loops 23 for detecting the Y coordinate.
N pieces of Y are arranged orthogonal to the X loop. The X loop and the Y loop are each formed in a substantially rectangular shape,
The length of the long side of the rectangular portion of the X loop is P2Y, and the length of the long side of the rectangular portion of the Y loop is P2X. FIG.
As shown in (B), the X loops are each formed to have a width (the length of the short side of the rectangular portion) P1, and the adjacent X loops are each overlapped at a pitch of P1 / 2.
Each Y loop is also formed to have a width P1, and adjacent Y loops are respectively overlapped at a pitch of P1 / 2.

In this embodiment, P1 = 50 mm
P2X = 680 mm, P2Y = 980 m
m. Also, m = 22 and n = 33. Also, in FIG. 4A, the sides of each loop are drawn so as not to overlap in order to make the arrangement of each loop easy to understand.
The short sides of the loops Y1, Y2, Y3,... Further, in this embodiment, the coordinate input pen 60 and the eraser 40 each include a coil for generating an alternating magnetic field, an oscillation circuit, a battery, and the like.

[Network Configuration] Next, the electronic blackboard 1
FIG. 5 is a block diagram showing a configuration of a network when data communication is performed between the network and another electronic whiteboard 1.
This will be described with reference to FIG. Here, a case where communication is performed between a plurality of rooms provided with the electronic whiteboard 1 in a company or between companies is described as an example. In the room 3 in the company 2, an electronic blackboard 1 and a P connected to the electronic blackboard 1
C100 and a LAN board 103 connected to the PC 100 are provided.
And the PC 100 connected to the electronic whiteboard 1 and the P
A modem 108 connected to C100 is provided. The LAN board 103 provided in each room 3 is LA
It is connected to the hub 105 by an N cable 104. The HUB 105 is connected to a server 106, and the server 106 can be connected to another company 5 via the Internet 300. The modem 108 provided in the room 4 can be connected to another company 5 from the telephone line 109 via the public switched telephone network 301. Although not shown, the other company 5 is provided with an electronic whiteboard 1 communicable via a PC, as in the company 2.

Here, the flow of data in the network will be described. Writing data stored on the electronic blackboard 1 provided in a certain room 3 is transmitted from the PC 100 to the LA.
The data is transmitted to PC 100 in room 3 designated via N board 103 and HUB 105. Then, the person who has received the data can use the monitor 100 provided in the PC 100.
a by displaying the received data on the printer 20 connected to the PC 100 (FIG. 3).
The content of the received data can be viewed by printing on the paper 203 with 0 (FIG. 3). In addition, the handwritten data is stored in, for example, TIFF (Tag Image File).
The file can be attached to the electronic mail as an image file in the format (Format) and transmitted from the server 106 to another company 5 via the Internet 300. This allows
The other company 5 can see the contents of the writing data by decoding the image file attached to the e-mail sent from the company 2.

[Main Electrical Configuration and Operation of Electronic Blackboard 1] Next, the main electrical configuration and operation of the electronic whiteboard 1 will be described with reference to FIG. 6, which shows the main electrical configuration in blocks. When a user using the electronic blackboard 1 (hereinafter, referred to as a user) inserts the power plug 12 of the power supply unit 14 into an outlet of a commercial power supply (for example, indoor 100 V), the heater power supply 14c rises, and the heater power supply 14c
The temperature of the heating wire 24 rises due to the current supplied from the heater. Thereby, the wire 22 in contact with the heating wire 24 is heated, and when the shape memory alloy forming the wire 22 exceeds the transformation temperature, the wire 22 starts transformation, and the writing sheet 20 is shown in FIG. Figure 2 from the folded state
The state changes to the spread state shown in FIG. Then, as shown in FIG. 2C, the writing sheet 20 has a flat shape without warping or waving. And wire 2
2 is transmitted to the thermocouple 27, and the temperature is detected by the temperature detection circuit 14a. When the detected temperature reaches a preset upper limit temperature, the switch circuit 14b operates,
The heater power supply 14c is turned off. That is, by the temperature control, the wire 22 maintains the stored shape,
The writing sheet 20 can maintain a flat shape.

Subsequently, when the user presses the power button 37 of the remote controller 30, the drive power supply 14d rises, and power is supplied from the drive power supply 14d to the circuit board 50, and the circuit board 50 is ready for use. The CPU 56 scans the X loops X1 to Xm by outputting a coil selection signal for sequentially selecting the X loops X1 to Xm to the X loop switching circuit 50a via the input / output circuit (I / O) 53. At this time,
When the user brings the pen tip of the coordinate input pen 60 into contact with the writing surface 21a, a voltage is induced by magnetic coupling between the alternating magnetic field output from the coordinate input pen 60 and one of the X loops, and a signal indicating the voltage is generated. Is amplified by the amplifier 50c. Then, a band pass filter (BPF) 50d
Extracts the frequency band of the alternating magnetic field output from the coordinate input pen 60 from the band of the amplified signal, and the output signal is subjected to amplitude detection by the amplitude detection circuit 51. The A / D conversion circuit 52 converts the detected signal into a digital signal corresponding to the amplitude, that is, the voltage value, and the digital signal is input to the CPU 56 via the input / output circuit (I / O) 53.
The signal output from the band pass filter (BPF) 50 d is converted into a square wave by the limiter circuit 54 and output to the FSK demodulation circuit 55. Subsequently, the FSK demodulation circuit 55 starts counting the cycle of the limiter output signal using the system clock when detecting the rise of the limiter output signal, and inputs and outputs the count value when detecting the next rise of the limiter output signal. Circuit (I / O)
Output to CPU 56 via 53. Subsequently, the CPU 56
Determines the pen attribute based on the input count value.

Subsequently, the CPU 56 sequentially stores the voltage values e1 to em of the voltages generated in the respective X loops by the alternating magnetic field output from the coordinate input pen 60 in the voltage value storage area of the RAM 59 in association with the coil numbers of the X loops. I do. Subsequently, the CPU 56 calculates the X coordinate of the coordinate input pen 60 according to the following procedure based on each voltage value stored in the voltage value storage area. Here, a case where the X coordinate Xn is calculated based on the voltage values e1 to em will be described as an example. First, the voltage values e1 to e stored in the voltage value storage area
m, the maximum voltage value emax is selected, and the voltage value emax is selected.
The coil number of the X coil that generated max (hereinafter referred to as max
Is stored in the RAM 59. And CPU5
6 determines the larger one of the voltage values emax ± 1 on both sides of emax, and stores the coil number (hereinafter referred to as max2) of the X coil that generated the determined voltage value in the RAM 59.

Subsequently, the CPU 56 compares the coil numbers max and max2 stored in the RAM 59 to determine whether the coil number max2 exists in the positive or negative direction of the X axis from the coil number max. If max2 ≧ max, the variable SIDE is set to 1
And if max2 <max, the variable SID
Set E to -1. Subsequently, the CPU 56

DIFF = e (max) −e (max2) (1)

Is calculated, and the position coordinates closest to the calculated DIFF are read out from the position coordinate table stored in the ROM 58, and set as OFFSET. Subsequently, the CPU 56

Xn = (P1 / 2) × max + OFFSET × SIDE (2)

Is calculated to obtain an X coordinate Xn. here,
(P1 / 2) × max is the X of the center of the coil number max.
Indicates coordinates. Then, the CPU 56 controls the FSK demodulation circuit 55
Is read, and a pen attribute is detected based on the count value. Subsequently, the CPU 56 executes a scan of each Y coil, and outputs a voltage value detected from each Y coil to RA
It is stored in the voltage value storage area for the Y coil of M59. Subsequently, the CPU 56 calculates the Y coordinate Yn of the pen 60 using the same method as the X coordinate calculation described above, and stores the pen attribute, the X coordinate Xn, and the Y coordinate Yn in a predetermined storage area of the RAM 59 in association with each other. .

The CPU 56 receives a switching signal generated by operating various buttons (FIG. 3B) provided on the remote controller 30 through the I / F circuit 57, and
Of the position coordinate data stored in the RAM 59, the position coordinates of the target page are converted into an appropriate format and
It outputs to the C100 or the printer 200 (FIG. 3A), sends or returns the page storing the position coordinate data in page units, or deletes the position coordinate data in page units.

[Effects of the Embodiment] As described above, when the electronic blackboard 1 of this embodiment is used, the writing sheet 20 is flexible and can be folded or rolled, so that it is easy to carry. It is. Further, a wire 22 formed of a shape memory alloy is attached around the writing sheet 20 of the electronic blackboard 1, and a heating wire 24 for heating the wire 22 is provided. When the writing sheet 20 is in a flat state in which the writing sheet 20 is not warped or wavy, the shape is stored in the wire 22, and when the writing sheet 20 is spread, the heating wire 2 is used.
By heating the wire 22 with 4, the writing sheet 20 can be made flat without warping or waving. Therefore, the writing surface 21a does not warp or undulate during use, so that writing performance can be improved.

[Other Embodiments] The design of the electronic whiteboard 1 according to the above-described embodiment can be changed as follows. (1) The wires 22 are provided only on a pair of opposing sides. (2) The writing sheet 20 is expanded from a form in which the writing sheet 20 is rounded into a cylindrical shape. (3) The heating wire 24 is wound around the wire 22. (4) Write the circuit board 50 on the writing sheet 2
It is detachably attached to 0. (5) An operation unit in place of the remote controller 30 is provided at an end of the writing sheet 20. (6)
An operation unit in place of the remote control 30 is detachably provided at an end of the writing sheet 20. (7) A dedicated stand for installing the electronic blackboard 1 is prepared, an operation unit is provided at a predetermined position of the stand, and the operation unit and the writing sheet 20 are detachably electrically connected to each other by terminals provided mutually. The material and the transformation temperature of the shape memory alloy forming the wire 22 are not limited to those described above.

Incidentally, the coordinate input pen 60 corresponds to the coordinate input means of the first aspect, the loop-shaped coil 23 corresponds to the loop-shaped conductor, and the writing sheet 20 corresponds to the sheet. The wire 22 corresponds to a shape memory alloy, and the heating wire 24 and the heater power supply 14c correspond to a heating unit.

[Brief description of the drawings]

1A is an external perspective explanatory view showing a main structure of an electronic blackboard, FIG. 1B is a cross-sectional view taken along the line AA of FIG. 1A, and FIG. () Is an explanatory diagram showing an enlarged part of the left end of FIG. 1 (B).

FIG. 2 (A) is a writing sheet 20 shown in FIG. 1 (A).
FIG. 2B is an explanatory view showing a state in which the writing sheet 20 shown in FIG. 2A is in the middle of spreading, and FIG. FIG. 4 is an explanatory diagram showing a shape in which the writing sheet 20 shown in FIG.

FIG. 3 (A) shows a P on the electronic blackboard 1 shown in FIG. 1 (A).
FIG. 4 is an explanatory diagram showing a state in which C and a printer are connected;
FIG. 3B is an explanatory diagram showing an enlarged view of the remote controller 30 provided in the electronic whiteboard 1 shown in FIG. 1A.

FIG. 4 (A) is an explanatory view showing a configuration of a loop-shaped coil with a part thereof omitted, and FIG. 4 (B) is a diagram showing FIG. 4 (A).
It is explanatory drawing which shows the width | variety and overlap pitch of the loop-shaped coil shown in FIG.

FIG. 5 is an explanatory diagram showing blocks of a network configuration when data communication is performed between the electronic whiteboard 1 and another electronic whiteboard 1;

FIG. 6 is an explanatory diagram showing the main electrical configuration of the electronic blackboard 1 by blocks.

[Explanation of symbols]

 Reference Signs List 1 electronic blackboard (coordinate reading device) 14 power supply unit 20 writing sheet (coordinate input sheet) 21 film 22 wire (shape memory alloy) 23 loop coil (loop conductive wire) 24 heating wire (heating means) 30 remote control 60 coordinate input pen

Continued on the front page F term (reference) 2F063 AA03 BA28 BA30 BB02 CA34 CA40 DA02 DA05 DB05 DD07 EB23 GA27 GA33 GA36 GA61 LA06 LA19 LA29 MA09 NA01 NA02 NA06 NA10 ZA10 5B068 AA05 AA15 BB14 BC09 BC15 BD02 BD17 BE06 CC11

Claims (1)

[Claims] 1. A coordinate reading device comprising a sheet on which a plurality of loop-shaped conductors for detecting a signal output from a coordinate input means are laid, wherein the sheet has flexibility and is located within a predetermined range around the sheet. A coordinate reading apparatus having a shape memory alloy mounted thereon and comprising a heating unit for heating the shape memory alloy.