WO2010023861A1

WO2010023861A1 - Digitizer capable of discriminating among indicators

Info

Publication number: WO2010023861A1
Application number: PCT/JP2009/004048
Authority: WO
Inventors: 小川保二
Original assignee: 株式会社ニューコム
Priority date: 2008-08-28
Filing date: 2009-08-24
Publication date: 2010-03-04
Also published as: JP2010055385A

Abstract

Provided is a digitizer capable of discriminating among a plurality of indicators from whether a driving signal and a detection signal are in equiphase or in antiphase without providing any electrical component in the indicators. The digitizer capable of discriminating among a plurality of indicators (100) is constituted of a driver loop line group (10), a detection loop line group (20), a detection surface (30) on which these loop line groups are arranged, a discrimination unit (40), and a detection unit (50). A plurality of U-shaped linear loop lines in the driver loop line group (10) are arranged in parallel with the longitudinal direction thereof and a plurality of U-shaped linear loop lines in the detection loop line group (20) are arranged in parallel with the longitudinal direction thereof, with the respective longitudinal directions being orthogonal to each other. The indicators (100) have tip members (101, 102), respectively, each formed of a magnetic material or a conductive material having a diameter almost as large as or smaller than the loop width of each loop line. The discrimination unit (40) discriminates whether the tip member is magnetic or conductive on the basis of whether the driving signal and the detection signal are in equiphase or in antiphase. On the basis of the change in the degree of electromagnetic coupling of the driver loop line group (10) and the detection loop line group (20), the detection unit (50) detects a position indicated by the indicator (100).

Description

Digitizer that can identify multiple indicators

The present invention relates to a digitizer that can identify a plurality of pointing devices, and more particularly, to a digitizer that can identify a plurality of pointing devices without providing an electrical component on the pointing device.

For example, there are optical type and electromagnetic induction type digitizers having an indicator identifying function. An example of an optical type digitizer is disclosed in Patent Document 1. This uses a light source, a polarizing plate, and a retroreflective frame provided around the detection surface to identify an indicator having a retroreflective member and an indicator having no retroreflective portion such as a finger, Each indicated position can be detected by the principle of triangulation.

Further, as an electromagnetic induction type digitizer, there is one disclosed in Patent Document 2, for example. First, radio waves of a predetermined frequency are transmitted by a plurality of loop coils orthogonal to the detection surface, and received by a resonance circuit provided in the indicator. At that time, the induced voltage is measured by receiving the radio wave transmitted from the resonance circuit that has received the radio wave with the same loop coil. By receiving this by sequentially switching the loop coils, the indicated position can be detected. Then, in the two indicating tools each having the resonant circuit in which the phase of the current at the resonant frequency of the resonant circuit is delayed by a predetermined time with respect to the phase of the voltage and the resonant circuit not delayed, the received signal received by these indicating tools The phase is different. Therefore, it is possible to identify the indicator using the phase change.

JP 2001-142629 A JP-A-63-70326

However, since the digitizer disclosed in Patent Document 1 uses the principle of triangulation, the position detection accuracy becomes worse as the distance from the light source increases, and the detection accuracy varies depending on the indicated position in the detection surface. was there. In addition, a retroreflective frame is required around the detection surface, and there are design limitations.

Moreover, since the digitizer disclosed in Patent Document 2 is provided with a resonance circuit in the indicator, the cost required for the indicator is high. Furthermore, the resonance circuit of the pointing device may change the inductance of the coil and the capacitance of the capacitor due to changes in ambient temperature. For this reason, in the digitizer disclosed in Patent Document 2, if there is a phase change due to an ambient temperature change or the like, there is a case where the digitizer is erroneously recognized in identifying the pointing tool. In order to prevent this, it is necessary to provide a predetermined compensation circuit or the like.

In view of such circumstances, the present invention is intended to provide a digitizer that can identify a plurality of indicators by whether the drive signal and the detection signal are in phase or in reverse phase without providing an electrical component in the indicator. is there.

In order to achieve the above-described object of the present invention, the digitizer of the present invention capable of identifying a plurality of pointing devices has a plurality of U-shaped linear drive loop wirings arranged in parallel in the longitudinal direction, and is driven by each. A detection loop wiring group in which a drive loop wiring group to which a signal is applied and a plurality of U-shaped linear detection loop wirings are arranged in parallel in the longitudinal direction and a detection signal is detected from each of the detection loop wiring groups. The wiring is arranged such that its longitudinal direction is orthogonal to the longitudinal direction of the drive loop wiring, a detection loop wiring group, a detection surface on which the driving loop wiring group and the detection loop wiring group are arranged, and a U-shaped driving loop An indicator indicated on the detection surface having a tip member made of a magnetic material or a conductor having a diameter substantially equal to or narrower than the loop width of the wiring and / or detection loop wiring, and the drive signal and the detection signal are in phase or reverse The identification unit for identifying whether the tip member of the indicator is a magnetic body or a conductor based on the phase, and the degree of electromagnetic coupling between the drive loop wiring group and the detection loop wiring group by indicating the pointer on the detection surface And a detecting unit that detects the indicated position of the pointing tool based on the change of the pointing tool.

Here, the driving loop wiring group is arranged so that each driving loop wiring overlaps with some of the other driving loop wirings, and the detection loop wiring group includes each detection loop wiring with some of the other detection loop wirings. You may arrange | position so that it may wrap.

Also, the identification unit may be configured to switch and identify the function to be given to the pointing device according to the identification result.

The indicator may have a tip member made of a magnetic material and a tip member made of a conductor, and the indicator may be provided with a feeding mechanism that switches these to the tip of the indicator. .

The digitizer of the present invention that can identify a plurality of indicators has an advantage that the indicator can be identified by whether the drive signal and the detection signal are in phase or in reverse phase without providing an electrical component in the indicator. . In addition, there is an advantage that the pointing tool can be accurately identified and the pointing position can be detected without being affected by the pointing position in the detection surface or a change in ambient temperature.

FIG. 1 is a schematic configuration diagram for explaining a digitizer of the present invention capable of identifying a plurality of pointing devices. FIG. 2 is a diagram for explaining the relationship between the drive signal and detection signal of the digitizer of the present invention. FIG. 3 is a schematic cross-sectional view for explaining an example of the pointing device of the digitizer of the present invention.

Hereinafter, the best mode for carrying out the present invention will be described with reference to the drawings. FIG. 1 is a schematic configuration diagram for explaining a digitizer of the present invention capable of identifying a plurality of pointing devices. As shown in the figure, the digitizer of the present invention comprises an indicator 100 and a position detection device for detecting this, and the position detection device comprises a drive loop wiring group 10, a detection loop wiring group 20, and a drive loop wiring. The detection surface 30 on which the group 10 and the detection loop wiring group 20 are arranged, an identification unit 40, and a detection unit 50 are included.

The drive loop wiring group 10 is configured by arranging a plurality of U-shaped straight drive loop wirings 10 _t1 to 10 _t8 in parallel in the longitudinal direction. A drive signal is applied to each drive loop wiring. Specifically, the oscillator 12 and the drive loop wiring switch 13 are used to sequentially connect the oscillator 12 to the drive loop wirings 10 _t1 to 10 _t8 . A high-frequency drive signal is applied to one end of each drive loop wiring, and the other end is connected to the ground. In the illustrated example, the drive loop wiring group 10 is configured by eight drive loop wirings 10 _t1 to 10 _t8 . However, this is merely an example, and the present invention is not limited to this. The number and size of each can be variously changed according to the size of the detection surface, the detection resolution, and the like.

Next, the detection loop wiring group 20 includes a plurality of U-shaped straight detection loop wirings 20 _r1 to 20 _r8 arranged in parallel in the longitudinal direction. The detection loop wirings 20 _r1 to 20 _r8 are arranged so that the longitudinal direction thereof is orthogonal to the longitudinal direction of the driving loop wirings 10 _t1 to 10 _t8 . And a detection signal is detected from each detection loop wiring. Note that one end of the detection loop wiring is connected to the synchronous detection unit 25, and the other end is connected to the ground. Specifically, using the detection loop wiring switch 23, the amplifier 24, and the synchronous detection unit 25, the synchronous detection unit 25 is sequentially connected to the detection loop wirings 20 _r1 to 20 _r8 , and the detection loop wiring group 20 The induced current or induced voltage is sequentially detected by the detection unit 50. The output from the oscillator 12 is also connected to the synchronous detection unit 25, and the product of the output from the oscillator 12 and the output from the detection loop wiring group 20 is taken and time-integrated. Specifically, the detection unit 50 measures a change in the amplitude of the induced current or the induced voltage. Note that a detection signal may be detected from all the detection loop wirings at once by providing a detection circuit separately for each detection loop wiring or combining a frequency filter circuit or the like. In the illustrated example, the detection loop wiring group 20 is configured by eight detection loop wirings. However, like the driving loop wiring, this is merely an example, and the present invention is not limited to this. The number of wirings can be variously changed according to the size of the detection surface, the detection resolution, and the like.

The drive loop wiring switch 13 and the detection loop wiring switch 23 are controlled by the microcomputer 60 so as to obtain a desired output. Specifically, first, the oscillator 12 is connected to the first drive loop line 10 _t1 via the drive loop line switch 13, and the amplifier 24 is connected to each of the detection loop lines 20 _r1 to 20 _r8 of the detection loop line group 20. Connect sequentially and measure the output signal at that time. Next, the oscillator 12 is connected to the second drive loop wiring 10 _t2 , and the amplifier 24 is sequentially connected to each of the detection loop wirings 20 _r1 to 20 _r8 of the detection loop wiring group 20, and the output signal at that time is synchronously detected. Measurement is performed by the detection unit 50 via the unit 25. By repeating this, it is possible to measure output signals at all positions where the intersection of each drive loop wiring and detection-side loop wiring on the detection surface 30 is an XY coordinate.

Here, on the detection surface 30 in the illustrated example, the drive loop wiring group 10 is arranged so that each drive loop wiring overlaps some of the other drive loop wirings. The detection loop wiring group 20 is also arranged so that each detection loop wiring overlaps with some of the other detection loop wirings. Specifically, as shown in the illustrated example, in order to increase the resolution between adjacent loop wirings, the arrangement pitch P of adjacent loop wirings is arranged narrower than the loop width W of the loop wiring, and partly overlaps. ing. For example, the loop width W of the loop wiring is 21 mm, for example, and the arrangement pitch P is 6 mm. The present invention is not necessarily limited to the overlapped ones as shown in the drawings, and may be arranged so as not to overlap with a predetermined interval.

Next, the pointing tool that is instructed on the detection surface configured as described above will be described. The pointing device of the digitizer of the present invention has a tip member made of a magnetic material or a conductor having a diameter substantially the same as or narrower than the loop width of the U-shaped drive loop wiring or detection loop wiring. Specifically, for example, the pointing tool 100 has a tip member 101 made of a magnetic material at the tip. The indicator 100 may have a tip member 102 made of a conductor at the tip. Such a tip member 101 or tip member 102 is configured to have a diameter narrower than the loop width W. That is, the pointing tool 100 has a size such that most of the tip member 101 or the tip member 102 falls inside the orthogonal loop wiring. Examples of the magnetic material used as the tip member include ferrite, alnico, and permalloy. Moreover, as a material of a conductor, copper, aluminum, etc. are mentioned, for example.

In the digitizer of the present invention, the tip member of the indicator is configured to have a diameter that is substantially the same as or narrower than the loop width of the loop wiring, thereby increasing the amplitude of the detection signal as will be described later. The direction of the phase of the detection signal detected depending on whether the magnetic field is a magnetic material or a conductive material is reversed. The drive loop wiring and the detection loop wiring are not necessarily limited to those having the same loop width, and the diameter of the tip member is also substantially the same as or narrower than the loop width of the loop wiring having the smaller loop width. What is necessary is just to be comprised so that it may become. In addition, the shape of the tip member is preferably circular and the tip is rounded in consideration of touch on the detection surface, but is not particularly limited thereto.

Now, in the pointing device and position detection device having such a configuration, first, the pointing position detection of the pointing device will be described first. The method of detecting the pointing position of the pointing tool is the same as that of the position detecting device using electromagnetic coupling, which has been filed by the inventors of the present application. Specifically, in a state in which the pointing tool 100 is not input on the detection surface 30, the drive loop wiring group 10 and the detection loop wiring group 20 are linearly orthogonal, and therefore are not electromagnetically coupled. Even if the group 10 is driven, no induced current or induced voltage is output from the detection loop wiring group 20. And, for example, when the pointing device 100 has a tip member 101 made of a magnetic material, when this is input on the detection surface 30, among the intersections of the drive loop wiring group 10 and the detection loop wiring group 20, The degree of electromagnetic coupling changes at the intersection near the indicated position of the pointing tool 100, and an induced current or induced voltage is output from the detection loop wiring group 20. Therefore, the detection unit 50 detects the indicated position coordinates of the pointing tool 100 placed on the detection surface 30 by detecting XY coordinates from which an output such as an induced current based on the change in the degree of electromagnetic coupling is obtained. It is possible.

Further, for example, when the pointing device 100 has a tip member 102 made of a conductor, when this is input on the detection surface 30, the intersection portion of the drive loop wiring group 10 and the detection loop wiring group 20 is input. Among them, the degree of electromagnetic coupling changes at the intersection near the indicated position of the pointing tool 100, and an induced current or induced voltage is output from the detection loop wiring group 20. Therefore, the detection unit 50 detects the XY coordinates from which the output of the induced current or the like based on the change in the degree of electromagnetic coupling is detected, thereby similarly indicating the indicated position coordinates of the pointing tool 100 placed on the detection surface 30. It is possible to detect.

Next, an identification unit that identifies a plurality of pointing devices in the digitizer of the present invention will be described. The identification unit 40 identifies whether the tip member of the indicator 100 is a magnetic body or a conductor based on whether the drive signal and the detection signal are in phase or in phase. A detection signal from the detection loop wiring group 20 is input to the identification unit 40 via the synchronous detection unit 25. The identification unit 40 detects the phase difference of the detection signal. Hereinafter, the phase of the detection signal will be described more specifically with reference to FIG.

FIG. 2 is a diagram for explaining the relationship between the drive signal and the detection signal of the digitizer of the present invention. 2A is a schematic perspective view for explaining the relationship between the drive loop wiring and the detection loop wiring, FIG. 2B is a graph showing the drive signal, and FIG. 2C is the tip of the magnetic body. It is a graph showing the detection signal in the case of the indicator of a member, and FIG.2 (d) is a graph showing the detection signal in the case of the indicator of the front-end | tip member of a conductor. In the figure, the same reference numerals as those in FIG. 1 denote the same parts.

As shown, when driving the driving loop line 10 _t by the oscillator 12, the drive loop line 10 _t flows drive current _{i t.} A drive signal driving current i _t, as shown in FIG. 2 (b), for example a sine wave. In such a state, the indicator 100 having a tip member having a diameter smaller than the loop width is input. Here, when an indicator 100 having a magnetic tip member 101 is input, the magnetic field in the direction perpendicular to the detection surface 30 increases as the current of the drive loop wiring 10 _t increases. At this time, an induced current is generated in the detection loop wiring 20 _r in a direction that prevents the change in the magnetic field. For example, when both the drive loop wiring 10 _t and the detection loop wiring 20 _r are configured by a right-handed loop in the same direction as in the illustrated example, the detection surface 30 increases as the current of the drive loop wiring 10 _t increases. since a downward magnetic field is increased with respect to, so as to prevent changes in the magnetic field, left-handed induced current is generated in the detection loop wiring 20 _r. That is, at this time, as shown in FIG. 2C, a detection signal having a phase opposite to that of the drive signal is detected.

On the other hand, when the indicator 100 having the conductor tip member 102 is input, the magnetic field in the direction perpendicular to the detection surface 30 increases as the current of the drive loop wiring 10 _t increases. At this time, in the conductor of the tip member 102, an eddy current is generated in a direction that prevents the change in the magnetic field. Next, due to the eddy current generated in the tip member 102, the magnetic field in the direction perpendicular to the detection surface 30 increases in the direction opposite to the direction of the magnetic field due to the increase in the current of the drive loop wiring _10t . In the detection loop wiring 20 _r , an induced current is generated in a direction that prevents the change in the magnetic field. For example, when both the drive loop wiring 10 _t and the detection loop wiring 20 _r are configured by right-handed loops in the same direction as in the illustrated example, the detection surface 30 increases as the current of the drive loop wiring 10 _t increases. Therefore, a left-handed eddy current is generated in the conductor of the tip member 102 so as to prevent this magnetic field. Further, to prevent the change of the upward magnetic field generated by the eddy currents, induced current right-handed is generated in the detection loop wiring 20 _r. That is, at this time, as shown in FIG. 2D, a detection signal in phase with the drive signal is detected.

Thus, it can be seen that the phase of the detected signal is reversed depending on whether the tip member of the indicator 100 is a magnetic body or a conductor. Therefore, by detecting the phases of the drive signal and the detection signal, it is possible to identify whether the tip member of the indicator 100 is a magnetic body or a conductor. If either the drive loop wiring or the detection loop wiring is left-handed as opposed to the illustrated example, the output detection signal is inverted. However, according to the present invention, the indicator is identified based on whether the drive signal and the detection signal are in phase or opposite phase, and according to the detection principle of the present invention, the current detected in the conductor and the magnetic body Therefore, the direction of winding the loop wiring is not particularly limited to the illustrated example.

The indicated position coordinate information and the identification information detected as described above are then sent to an electronic computer such as a personal computer and used as input information to predetermined software or the like. In the above description, the identifying unit identifies the pointing device. However, the present invention is not limited to this, and the identifying unit identifies only whether the phase is the same phase or the opposite phase, and sends it to the computer. It is of course possible to identify various pointing tools on the electronic computer after being sent.

According to the digitizer of the present invention, as described above, it is possible to identify a plurality of indicators by using the tip member of the indicator as a conductor and a magnetic material. Thereby, in the identification part, it becomes possible to switch and identify the function to be given to the pointing tool according to the identification result. That is, for example, when the detection signal is in phase with the drive signal, the input indicator can be recognized as a black pen, and when the detection signal is in reverse phase, the input indicator can be recognized as an eraser. . Further, by inputting the pointing tool having a tip member made of a magnetic material and the pointing tool having a tip member made of a conductor separately for each of two persons, each person's input is recognized and the pointing position is recognized. It is also possible to detect.

Further, a tip member made of a magnetic material and a tip member made of a conductor may be provided in one indicator. For example, a magnetic body is provided on one end side of the pointing device main body, and a conductor is provided on the other end side as a tip member, so that one pointing device has two functions like a pencil with an eraser. It is also possible.

Alternatively, a tip member made of a magnetic material and a tip member made of a conductor may be provided in one indicator, and these may be switched and fed to the tip of the indicator. FIG. 3 is a schematic cross-sectional view for explaining an example of the pointing device of the digitizer of the present invention. In the figure, the same reference numerals as those in FIG. 1 denote the same parts. As illustrated, the pointing device 100 includes a tip member 101 made of a magnetic material and a tip member 102 made of a conductor. The tip member 101 and the tip member 102 are each connected to the feeding mechanism 110 via a shaft portion. These are housed in a housing 105 that defines an outer frame of the pointing device 100. The feeding mechanism 110 rotates the rotating shaft 107 about the longitudinal direction of the pointing device 100 so as to exclusively feed the tip member 101 or the tip member 102 connected to the feeding mechanism 110 out of the housing 105. It is composed of.

When the indicator configured as described above is used, the digitizer of the present invention detects when the input is performed on the detection surface by the indicator 100 that has extended the tip member 101 and by the indicator 100 that has extended the tip member 102. When the input is performed on the surface, the phase of the detection signal with respect to the drive signal is reversed, so that the identification unit can identify which tip member has been fed out and input.

As described above, according to the digitizer of the present invention, the indicator only needs to be provided with a magnetic body or a conductor at the tip thereof, and there is no need to provide an electrical component. Tools can be configured very inexpensively. In addition, since the phase of the detection signal with respect to the drive signal is always reversed between the magnetic body and the conductor, stable identification is possible without being affected by the surrounding environment.

It should be noted that the digitizer of the present invention capable of identifying a plurality of pointing devices is not limited to the above illustrated example, and it is needless to say that various changes can be made without departing from the gist of the present invention. For example, the digitizer of the present invention discriminates the indicator according to whether it is the same phase or the opposite phase, but it is also possible to combine other identification methods by providing an electrical component on the indicator. Moreover, you may combine the system which identifies an indicator based on the thickness and shape by changing the thickness and shape of the front-end | tip member of an indicator.

DESCRIPTION OF SYMBOLS 10 Drive loop wiring group 12 Oscillator 13 Drive loop wiring switch 20 Detection loop wiring group 23 Detection loop wiring switch 24 Amplifier 25 Synchronous detection part 30 Detection surface 40 Identification part 50 Detection part 60 Microcomputer 100 Pointer 101,102 Tip member 105 Housing 107 Rotating shaft 110 Feeding mechanism

Claims

A digitizer capable of identifying a plurality of pointing devices, the digitizer comprising:
A plurality of U-shaped linear drive loop wirings arranged in parallel in the longitudinal direction, and a drive loop wiring group to which a drive signal is applied to each;
A plurality of U-shaped linear detection loop wirings are arranged in parallel in the longitudinal direction, and a detection loop wiring group from which detection signals are detected from each of the U-shaped linear detection loop wirings. A detection loop wiring group arranged to be orthogonal to the longitudinal direction of
A detection surface on which the drive loop wiring group and the detection loop wiring group are disposed;
An indicator indicated on the detection surface, having a tip member made of a magnetic material or conductor having a diameter substantially equal to or narrower than the loop width of the U-shaped drive loop wiring and / or detection loop wiring;
Based on whether the drive signal and the detection signal are in phase or in reverse phase, an identification unit that identifies whether the tip member of the indicator is a magnetic body or a conductor;
A detection unit for detecting a pointing position of the pointing tool based on a change in the degree of electromagnetic coupling between the driving loop wiring group and the detection loop wiring group by pointing the pointing tool on the detection surface;
A digitizer comprising:
The digitizer according to claim 1, wherein the drive loop wiring group is arranged such that each drive loop wiring overlaps with some of the other drive loop wirings, and each detection loop wiring includes the other detection loop wirings. Digitizer characterized in that it is arranged to overlap some of the detection loop wiring.
3. The digitizer according to claim 1, wherein the identification unit switches and identifies a function to be given to the pointing tool according to the identification result.
The digitizer according to any one of claims 1 to 3, wherein the indicator has a tip member made of a magnetic material and a tip member made of a conductor, and the indicator further switches between these. A digitizer comprising a feeding mechanism for feeding to the tip of an indicator.