Patent Description:
A drawing system is known in which an animation image or the like is generated by performing drawing on a coordinate input device referred to as a digitizer through continuous position indication by an electronic pen. In this case, an operator performs position indicating operation for generating a drawing image in a state in which the electronic pen is in contact with the input surface of a tablet device incorporating the digitizer or in a state in which the electronic pen is not in contact with the input surface of the tablet device but is positioned in an upward region in which position detection is possible (hovering state). The digitizer detects a position indicated by the electronic pen, generates a drawing image as a result of the detection, and displays the drawing image on a display screen. The operator performs drawing while checking the drawing image displayed on the display screen.

Systems and applications have recently emerged which are capable of drawing representation (for example rotation, deformation, or the like) of a drawing image displayed on a two-dimensional display screen such that the drawing image is visually a three-dimensional image. In this case, movement (gesture) of, for example, a hand or a finger of the operator is detected by using a movement sensor, and drawing representation processing is performed on the basis of the detected movement (gesture).

Conventionally, a process of generating a two-dimensional drawing image on the basis of detection of the position indicated by the electronic pen by the digitizer and a process of drawing representation and handling of the two-dimensional image such that the two-dimensional image is a three-dimensional image are performed as separate processes independently of each other.

A user interface enabling both of position indication input as described above and operating input such as a gesture or the like has been provided (see Patent Document <NUM> and Patent Document <NUM>, for example).

Patent Document <NUM> discloses a touch controller configured to switch from a hover event detection mode to a gesture event detection mode in response to a signal from a motion sensor.

In addition, Patent Document <NUM> discloses controller means for alternately determining positional information detected via a touch sensor type display and positional information detected via noncontact detecting means.

<CIT>
discloses a gesture detection system including an input device with a touch sensitive surface and a contact-free detection system; and a controller configured to determine characteristic parameters for the position in three-dimensional space of a user input object and select an operational mode of the input device based on the position of the user input object. <CIT> discloses a method for the contactless detection and recognition of gestures in a three-dimensional movement space (3D gestures). <CIT> discloses data representative of a proximity heuristic specifying a plurality of levels of an object detection zone associated with a display screen is maintained, an object is detected within the object detection zone, one of the levels is selected based on at least one attribute of the object, and an action associated with the selected level is performed. <CIT> discloses a method capable of making various modifications to widgets, graphic objects, or images, which are displayed on a display device, according to motions of a plurality of input units such as finger or stylus pen, with the use of a three-dimensional multi-sensor configured to detect the motions of the input units in a space, without touching the display device. <CIT> discloses a information processing system is provided with an input device <NUM> for receiving an input handwritten by an operator and generating coordinates data corresponding to a corresponding input trace, and an image processor for generating displaying data for superposing displaying data for a display device upon the coordinates data from the input device to display them. <CIT> discloses an apparatus for recognizing a proximity motion using sensors, which include a first sensor to sense a first input region, a second sensor to sense a second input region distinct from the first input region, and an information transfer controller to transfer information related to a transition, between the first sensor and the second sensor.

However, the method of switching in response to the signal from the motion sensor as in Patent Document <NUM> requires the inclination of a device to be changed as needed for the switching.

In addition, in the case of Patent Document <NUM>, switching between the touch sensor type display and the noncontact detecting means is performed on a time-division basis, and temporal resolution of each is decreased.

It is an object of the present invention to provide a spatial position indication system that can solve the above problems.

In order to solve the above problems, there is provided a spatial position indication system including:.

In the spatial position indication system having the above-described configuration, a detection region for the instruction input by the electronic pen in the indicated position detecting device unit is a region including the hover region over the input surface for receiving the instruction input by the electronic pen. The spatial position detecting device unit is configured to be able to detect the position of the electronic pen in the spatial region including at least a part of the above-described hover region of the indicated position detecting device unit.

The selecting unit performs selection control so as to use one of indicated position detection output from the indicated position detecting device unit and spatial position detection output from the spatial position detecting device unit according to the separation distance of the electronic pen from the input surface of the indicated position detecting device unit. An operator of the electronic pen can thereby perform operation while seamlessly switching between the indicated position detecting device unit and the spatial position detecting device by merely changing the separation distance of the electronic pen from the input surface of the indicated position detecting device unit.

Embodiments of a spatial position indication system according to the present invention will hereinafter be described with reference to the drawings.

<FIG> is a diagram illustrating an example of a general configuration of a first embodiment of a spatial position indication system according to the present invention. As illustrated in <FIG>, the spatial position indication system according to the present first embodiment includes an electronic pen <NUM> and a tablet device <NUM>. The tablet device <NUM> in the present embodiment has an internal configuration as illustrated in <FIG>. Schematically, a position indicated by the electronic pen <NUM>, the position being detected by an indicated position detecting device unit <NUM>, is used when a height position in a Z-axis direction from the input surface of the tablet device <NUM> to the pen point of the electronic pen <NUM> is smaller than a critical height position Lz to be described later (when the height position is a height position B1 in <FIG>, for example). On the other hand, a position indicated by the electronic pen <NUM>, the position being detected by a spatial position detecting device unit <NUM>, is used when the height position in the Z-axis direction from the input surface of the tablet device <NUM> to the pen point of the electronic pen <NUM> is equal to or higher than the critical height position Lz (when the height position is a height position B2 in <FIG>, for example). In general, the accuracy of position detection by the indicated position detecting device unit <NUM> is higher than the accuracy of position detection by the spatial position detecting device unit <NUM>. It is therefore preferable to continue to use the position detection by the indicated position detecting device unit <NUM> when the electronic pen <NUM> is separated from the input surface of the tablet device <NUM> for receiving an instruction input and is positioned in a hover region above the input surface, and use the position detection by the spatial position detecting device unit <NUM> when the height position is equal to or higher than the critical height position Lz.

The tablet device <NUM> of the spatial position indication system according to the present first embodiment includes a liquid crystal display (LCD) <NUM> as an example of a display unit. A display screen 201D of the LCD <NUM> is disposed on the top surface of a casing <NUM>.

In the tablet device <NUM>, a sensor unit <NUM> of an indicated position detecting device unit (hereinafter referred to as a digitizer) <NUM> that detects a position indicated by the electronic pen <NUM> is disposed on the back side of the LCD <NUM> in a state of being superposed on the LCD <NUM>. As illustrated in <FIG>, the digitizer <NUM> includes the sensor unit <NUM> and a position detecting circuit <NUM>.

Though not illustrated, the sensor unit <NUM> is formed by respectively arranging a plurality of loop coils in a horizontal direction (X-axis direction) of the casing <NUM> of the tablet device <NUM> and a vertical direction (Y-axis direction) of the casing <NUM>. In the present example, the digitizer <NUM> is of an electromagnetic induction type. However, the present embodiment is not limited to this.

On the other hand, the electronic pen <NUM> includes a resonance circuit (not illustrated) constituted of a coil and a capacitor on a pen point side. Signals are sent and received between the electronic pen <NUM> and the sensor unit <NUM> of the digitizer by electromagnetic induction coupling between the loop coils of the sensor unit <NUM> of the digitizer <NUM> and the resonance circuit of the electronic pen <NUM>. The electronic pen <NUM> is also of an electromagnetic induction type. However, the present embodiment is not limited to this.

The position detecting circuit <NUM> of the digitizer <NUM> supplies a signal to the electronic pen <NUM> through the loop coils of the sensor unit <NUM>, receives a signal from the electronic pen <NUM> through the loop coils, and detects a position indicated by the electronic pen <NUM> in a detection region of the sensor unit <NUM> on the basis of the received signal. Incidentally, in the present embodiment, the digitizer <NUM> is configured to detect a position indicated by the pen point of the electronic pen <NUM>.

In the present example, the loop coils of the sensor unit <NUM> of the digitizer <NUM> are arranged so as to cover substantially the entire area of the display screen 201D of the LCD <NUM>. Substantially the same region as the entire surface area of the display screen 201D is an input surface <NUM> (part enclosed by a dotted line in <FIG>) for input of the electronic pen <NUM> to the sensor unit <NUM>.

In the present embodiment, a position detection region in which the position indicated by the electronic pen <NUM> can be detected by the digitizer <NUM> includes not only a planar region when the pen point of the electronic pen <NUM> is in contact with the input surface <NUM> of the digitizer <NUM> but also a spatial region (the hover region of a hovering state of the electronic pen <NUM>) in which the pen point of the electronic pen <NUM> is not in contact with the input surface <NUM> of the digitizer <NUM> and is separated from the input surface <NUM> in a direction orthogonal to the input surface <NUM> (the Z-axis direction orthogonal to an X-axis direction and a Y-axis direction) but the position indicated by the electronic pen <NUM> can be detected through signal transmission and reception by electromagnetic coupling.

For example, supposing that a position P0 at an upper left corner of the input surface <NUM> of the digitizer <NUM> is set as coordinates ((X, Y, Z) = (<NUM>, <NUM>, <NUM>)) of an origin in the X-axis direction, the Y-axis direction, and the Z-axis direction in <FIG>, a position detection region DT in which the digitizer <NUM> can detect the position indicated by the electronic pen <NUM> is a planar region of the input surface <NUM> and a rectangular parallelepipedic spatial region over the input surface <NUM>, as indicated by hatching in <FIG>.

Specifically, letting Lx be the length in the X-axis direction of the input surface <NUM> of the digitizer <NUM>, letting Ly be the length in the Y-axis direction of the input surface <NUM> of the digitizer <NUM>, and letting Lz be a critical height position in the Z-axis direction at which position a hovering state can be detected, as illustrated in <FIG>, a region surrounded by coordinate point positions of eight points P0 (<NUM>, <NUM>, <NUM>), P1 (Lx, <NUM>, <NUM>), P2 (Lx, Ly, <NUM>), P3 (<NUM>, Ly, <NUM>), P4 (<NUM>, <NUM>, Lz), P5 (Lx, <NUM>, Lz), P6 (Lx, Ly, Lz), and P7 (<NUM>, Ly, Lz) as illustrated in <FIG> is the position detection region DT of the digitizer <NUM>.

The tablet device <NUM> according to the present first embodiment further includes the spatial position detecting device unit <NUM> as means for detecting the spatial position of the electronic pen <NUM> separately from the digitizer <NUM>. As illustrated in <FIG>, a spatial position detecting member <NUM> of the spatial position detecting device unit <NUM> is disposed on the top surface of the casing <NUM>. The spatial position detecting member <NUM> in the present example includes an invisible light sensor (for example an infrared light emitting unit (infrared light emitting diode (LED)) and an infrared camera or the like), though not illustrated. However, the present embodiment is not limited to this. Another sensor such as a visible light sensor or the like or a combination of these sensors may be used. In addition, the spatial position of the electronic pen <NUM> may be detected with the critical height position raised by increasing the frequency of an electromagnetic wave emitted from the digitizer <NUM> in place of the spatial position detecting member <NUM> or in addition to the spatial position detecting member <NUM>. That is, it suffices, for example, to normally detect the position of the electronic pen <NUM> in the spatial region including the input surface of the digitizer <NUM> and the hover region at a first frequency, and switch to a second frequency higher than the first frequency and detect the spatial position of the electronic pen <NUM> at a second critical height position higher than a first critical height position at the first frequency.

The infrared light emitting unit of the spatial position detecting member <NUM> of the spatial position detecting device unit <NUM> sets a spatial region including at least a part of the position detection region DT of the digitizer as a search region, and emits infrared light so as to search for a thing present in the search region (which thing will be referred to as an object). That is, the infrared light emitting unit of the spatial position detecting member <NUM> emits infrared light so as to search a space including at least a part of the position detection region DT of the digitizer. Then, the infrared camera of the spatial position detecting member <NUM> detects the presence and position of the object by receiving reflected light of the infrared light from the object present in the spatial region. As described earlier, in the present embodiment, the object detected by the spatial position detecting device unit <NUM> is the electronic pen <NUM>, and for example the pen point position of the electronic pen <NUM> is detected.

The spatial position detecting device unit <NUM> in the second embodiment is configured to detect the spatial position of the pen point of the electronic pen <NUM> in consideration of continuity with the position indicated by the electronic pen <NUM> which position is detected by the digitizer <NUM>. However, the present embodiment is not limited to this. The spatial position detecting device unit <NUM> may be configured to detect the position(s) of another one or a plurality of parts of the electronic pen <NUM>. The tablet device <NUM> in the present embodiment can be configured to detect a gesture performed by an operator of the electronic pen <NUM> from movement of the pen point of the electronic pen <NUM> which movement is obtained from the spatial position of the pen point, the spatial position being detected by the spatial position detecting device unit <NUM>.

A spatial position detecting circuit <NUM> (see <FIG>) of the spatial position detecting device unit <NUM> detects the position of the object, or the pen point position of the electronic pen <NUM> in the present example, within the above-described large spatial region from light reception information (a light receiving direction, a difference between a light emission time and a light reception time, and the like) of the reflected light received by the infrared camera. The spatial position detecting device unit <NUM> in the present example detects the movement of the pen point position of the electronic pen <NUM> within the spatial region. In the present specification, the spatial region as a target searched by the spatial position detecting device unit <NUM> will be referred to as a movement detection spatial region MD for convenience.

The space coordinate system of the movement detection spatial region MD of the spatial position detecting device unit <NUM> is set independently of the space coordinate system of the position detection region DT of the digitizer <NUM>. In <FIG>, the three axes of the space coordinate system of the movement detection spatial region MD are set as an Xs-axis, a Ys-axis, and a Zs-axis by using a suffix s, and are illustrated so as to be differentiated from the X-axis, Y-axis, and Z-axis of the space coordinate system of the detection region DT of the digitizer <NUM>. In this case, the movement detection spatial region MD of the spatial position detecting device unit <NUM> is defined such that, in the present example, as illustrated in <FIG>, the central position of a part in which the spatial position detecting member <NUM> is installed in the casing <NUM> of the tablet device <NUM> is set as the origin position of the space coordinate system of the movement detection spatial region MD.

Incidentally, in <FIG>, the respective directions of the Xs-axis, the Ys-axis, and the Zs-axis are illustrated as the same directions as the respective directions of the X-axis, the Y-axis, and the Z-axis for convenience. However, the respective directions of the Xs-axis, the Ys-axis, and the Zs-axis can be different from the respective directions of the X-axis, the Y-axis, and the Z-axis because of the optical axis direction of the infrared light emitting unit and the infrared camera constituting the spatial position detecting member <NUM>.

However, in the present embodiment, positional information on the position of the pen point of the electronic pen <NUM> can be subjected to coordinate transformation using spatial position correction information to be described later, by using a region common to the space coordinate system of the position detection region DT of the digitizer <NUM> and the space coordinate system of the movement detection spatial region MD of the spatial position detecting device unit <NUM>. That is, the space coordinate system of the movement detection spatial region MD of the spatial position detecting device unit <NUM> is disposed so as to include at least a part of the space coordinate system of the position detection region DT of the digitizer <NUM> as the common region.

Incidentally, when the respective directions of the Xs-axis, the Ys-axis, and the Zs-axis are the same directions as the respective directions of the X-axis, the Y-axis, and the Z-axis, the space coordinate system of the position detection region DT of the digitizer <NUM> and the space coordinate system of the movement detection spatial region MD can be treated as one common space coordinate system by considering a difference between the origin positions of the two space coordinate systems. That is, letting, for example, Δx, Δy, and Δz be offset values in the X-axis direction, the Y-axis direction, and the Z-axis direction, respectively, between the origin position of the space coordinate system of the position detection region DT of the digitizer <NUM> and the origin position of the space coordinate system of the movement detection spatial region MD, a coordinate value (Xs, Ys, Zs) in the space coordinate system of the movement detection spatial region MD can be transformed into a coordinate value (X, Y, Z) in the space coordinate system of the position detection region DT of the digitizer <NUM> by obtaining Xs - Δx (= X), Ys - Δy (= Y), and Zs - Δz (= Z).

However, in the tablet device <NUM> according to the present first embodiment, as described above, the respective directions of the X-axis, the Y-axis, and the Z-axis can be different from the respective directions of the Xs-axis, the Ys-axis, and the Zs-axis in the space coordinate system of the position detection region DT of the digitizer <NUM> and the space coordinate system of the movement detection spatial region MD, the space coordinate systems being provided independently of each other. In addition, even in a case where the respective directions of the X-axis, the Y-axis, and the Z-axis and the respective directions of the Xs-axis, the Ys-axis, and the Zs-axis are the same, it is difficult to define the offset values between the origin positions accurately, and the offset values may differ for each tablet device <NUM>.

Then, a coordinate position in the two space coordinate systems becomes different. For example, in a case where the pen point position of the electronic pen <NUM> is indicated by a cursor such as an arrow or the like on the display screen 201D, a jump may occur from the display position of a solid line cursor CS to the state of a broken line cursor CS', as illustrated in <FIG>, when switching is performed between the two space coordinate systems, that is, the space coordinate system of the position detection region DT of the digitizer <NUM> and the space coordinate system of the movement detection spatial region MD. Therefore, a user attempting to input a drawing image needs to indicate the indicated position again.

Accordingly, the present first embodiment generates correction information for an offset between the space coordinate system of the detection region DT of the digitizer <NUM> and the space coordinate system of the movement detection spatial region MD by utilizing a fact that at least a part of the position detection region DT of the digitizer <NUM> is a spatial region shared with the movement detection spatial region MD. In the present example, a coordinate value corrected for the offset between the coordinate value (X, Y, Z) in the space coordinate system of the position detection region DT of the digitizer <NUM> and the coordinate value (Xs, Ys, Zs) in the space coordinate system of the movement detection spatial region MD, the coordinate value (Xs, Ys, Zs) being detected by the spatial position detecting circuit <NUM> of the spatial position detecting device unit <NUM>, can be obtained by transforming the coordinate value (X, Y, Z) into the coordinate value (Xs, Ys, Zs). The correction information for the transformation will next be described.

Equation <NUM> represents a determinant for linear transformation of the coordinate value (Xs, Ys, Zs) in the space coordinate system of the movement detection spatial region MD which coordinate value is detected by the spatial position detecting circuit <NUM> of the spatial position detecting device unit <NUM> into the coordinate value (X, Y, Z) in the space coordinate system of the position detection region DT of the digitizer <NUM>. This determinant has three rows and three columns. The elements of the determinant are expressed by aij (i, j = <NUM>, <NUM>, <NUM>). <NUM>] <MAT>.

In the present first embodiment, the correction information for transformation between the space coordinate system of the detection region DT of the digitizer and the space coordinate system of the movement detection spatial region MD is generated by utilizing a fact that at least a part of the position detection region DT of the digitizer is a spatial region shared with the movement detection spatial region MD.

Specifically, as illustrated in <FIG>, the positions of at least three points Pa, Pb, and Pc within the spatial region common to the position detection region DT of the digitizer and the movement detection spatial region MD are specified, and the coordinate value (X, Y, Z) of each of the points in the space coordinate system of the position detection region DT of the digitizer <NUM> and the coordinate value (Xs, Ys, Zs) of each of the points in the space coordinate system of the movement detection spatial region MD are obtained from the respective devices. Ideally, the coordinate values obtained from these devices are the same, but usually these coordinate values do not coincide with each other unless calibration is performed. In general, the accuracy of position detection of the digitizer <NUM> is higher than the accuracy of position detection of the spatial position detecting device unit <NUM>. It is therefore preferable to adjust the coordinate value in the space coordinate system of the movement detection spatial region MD of the spatial position detecting device unit <NUM> to the coordinate value in the space coordinate system of the position detection region DT of the digitizer <NUM>.

Three equations are obtained for each point whose position is specified within the common region when the corresponding coordinate value (X, Y, Z) in the space coordinate system of the position detection region DT and the corresponding coordinate value (Xs, Ys, Zs) in the space coordinate system of the movement detection spatial region MD are substituted into Equation <NUM>. At least nine equations for a<NUM> to a<NUM> are obtained by specifying the positions of at least three points within the common region. The value of each of a<NUM> to a<NUM> can therefore be obtained. In addition, the transformation between the space coordinate system of the detection region DT of the digitizer and the space coordinate system of the movement detection spatial region MD is not limited to the above-described method, but learning based on machine learning using the coordinate values of at least three points in the common region, calibration by the user, or the like may be used.

As described above, the tablet device <NUM> according to the first embodiment is configured such that at least a part of the position detection region DT of the digitizer <NUM> is included within the movement detection spatial region MD of the spatial position detecting device unit <NUM>. That is, the tablet device <NUM> is configured such that the movement detection spatial region MD of the spatial position detecting device unit <NUM> has at least a part of the position detection region DT of the digitizer <NUM> as the common region.

The tablet device <NUM> according to the present embodiment is configured to perform switching as to whether to use the position indicated by the electronic pen <NUM> which position is detected by the digitizer <NUM> (first position) or to use the position of the electronic pen <NUM> in the spatial region which position is detected by the spatial position detecting device unit <NUM> (second position) according to a separation distance (separation distance in the Z-axis direction) of the pen point position of the electronic pen <NUM> from the input surface <NUM> of the sensor unit <NUM> of the digitizer <NUM>.

Specifically, as illustrated in <FIG>, letting θth be the separation distance (separation distance in the Z-axis direction) as a switching point from the input surface <NUM>, when the separation distance of the electronic pen <NUM> from the input surface <NUM> is smaller than θth, the digitizer <NUM> of the tablet device <NUM> operates as a device that detects the position indicated by the electronic pen <NUM> in the position detection region DT and performs processing according to the detected indicated position. On the other hand, when the separation distance of the electronic pen <NUM> from the input surface <NUM> is larger than θth, the tablet device <NUM> is switched such that the spatial position detecting device unit <NUM> operates as a device that detects the position of the electronic pen <NUM> within the spatial region and performs processing according to the position.

In the present embodiment, the separation distance (separation distance in the Z-axis direction) θth as the switching point from the input surface <NUM> is set equal to or less than a critical height distance Lz in the Z-axis direction at which distance the digitizer <NUM> can detect the hovering state of the electronic pen <NUM>. In the present example, as illustrated in <FIG>, the separation distance θth as the switching point from the input surface <NUM> is set equal to the critical height distance Lz in the Z-axis direction at which distance the digitizer <NUM> can detect the hovering state of the electronic pen <NUM>, that is, a length Lz in the Z-axis direction of the position detection region DT.

Specifically, the tablet device <NUM> is switched so as to use a result of detection of the position of the electronic pen <NUM> by the digitizer <NUM> when the electronic pen <NUM> is present within the position detection region DT of the digitizer <NUM> and use a result of detection of the movement of the electronic pen <NUM> by the spatial position detecting device unit <NUM> when the electronic pen <NUM> is present on the outside of the position detection region DT of the digitizer <NUM>. In addition, drawing processing is switched according to the switching.

In the present embodiment, the signal level (signal strength) of a signal received from the electronic pen <NUM> in the sensor unit <NUM> of the digitizer <NUM> is a value according to the separation distance, and therefore the tablet device <NUM> detects the separation distance (separation distance in the Z-axis direction) of the pen point position of the electronic pen <NUM> from the input surface <NUM> of the sensor unit <NUM> of the digitizer <NUM> on the basis of the signal level of the signal received from the electronic pen <NUM>.

Description will next be made of an example of constituent parts of the tablet device <NUM> that implements the above. Specifically, the position detecting circuit <NUM> constituting the digitizer <NUM> supplies a detection output of the position indicated by the electronic pen <NUM> as one input signal to a selecting circuit <NUM>. Incidentally, information supplied from the position detecting circuit <NUM> to the selecting circuit <NUM> includes information on a pen pressure applied to the electronic pen <NUM> in addition to the detection output of the position indicated by the electronic pen <NUM>. This pen pressure information indicates whether the electronic pen <NUM> is in contact with the input surface <NUM>, and makes it possible to draw a line drawing with a thickness corresponding to the magnitude of the pen pressure when the line drawing is drawn.

In addition, the spatial position detecting circuit <NUM> of the spatial position detecting device unit <NUM> supplies a detection output of the spatial position of the electronic pen <NUM> to a spatial position coordinate correcting circuit <NUM>. The spatial position coordinate correcting circuit <NUM> is supplied with the elements a<NUM> to a<NUM> of the determinant illustrated in the above-described (Equation <NUM>) from a correction information memory <NUM>. The spatial position coordinate correcting circuit <NUM> transforms the coordinate information in the space coordinate system of the spatial position detecting device unit <NUM> into coordinate information in the space coordinate system of the digitizer <NUM> by performing operation of the determinant of Equation <NUM> using the elements supplied from the correction information memory <NUM>. The spatial position coordinate correcting circuit <NUM> then supplies a coordinate output after the transformation to a gesture detecting circuit <NUM>.

The gesture detecting circuit <NUM> detects movement (gesture) of the pen point of the electronic pen <NUM> on the basis of the coordinate output from the spatial position coordinate correcting circuit <NUM>, and supplies a resulting detection output as another input signal of the selecting circuit <NUM>.

In the present embodiment, the position detecting circuit <NUM> of the digitizer <NUM> supplies a separation distance detecting circuit <NUM> with information regarding the signal level of a signal received from the electronic pen <NUM>. The separation distance detecting circuit <NUM> in the present embodiment detects the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> from the signal level of the signal received from the electronic pen <NUM>. The separation distance detecting circuit <NUM> then supplies information regarding the detected separation distance to a selection control signal generating circuit <NUM>.

The selection control signal generating circuit <NUM> generates a selection control signal SE that controls the selecting circuit <NUM> so as to select the detection output of the digitizer <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is equal to or smaller than the distance Lz, and controls the selecting circuit <NUM> so as to select the detection output of the gesture detecting circuit <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is larger than the distance Lz. The selection control signal generating circuit <NUM> performs selection control of the selecting circuit <NUM> by the generated selection control signal SE.

The selecting circuit <NUM> selects either the one input or the other input according to the selection control signal SE, and supplies the input to a drawing processing circuit <NUM>.

The drawing processing circuit <NUM> includes: a pen drawing processing unit <NUM> that draws a fine line drawing or the like on the basis of the detection output of the position indicated by the electronic pen <NUM> from the digitizer <NUM>; and a gesture processing unit <NUM> that performs drawing processing based on the movement (gesture) detected on the basis of the spatial position of the electronic pen <NUM> from the spatial position detecting device unit <NUM>. The drawing processing circuit <NUM> is supplied with a switching control signal SW from the switching signal generating circuit <NUM>. The drawing processing circuit <NUM> switches between the pen drawing processing unit <NUM> and the gesture processing unit <NUM> so as to be interlocked with the switching of the switch circuit <NUM>, and performs drawing processing of a three dimensional (3D) drawing image.

3D drawing image information generated by the drawing processing circuit <NUM> is, in the present example, supplied to a display unit <NUM> formed by an LCD through a display drive circuit <NUM>, and is displayed on the display screen 201D of the display unit <NUM>.

<FIG> illustrates an example of the 3D drawing image displayed on the display screen 201D of the display unit <NUM>. In the present embodiment, as illustrated in <FIG>, the display screen 201D displays a present mode display <NUM> that notifies the user whether the switching state of the switch circuit <NUM> is on the digitizer <NUM> side (tablet mode) or on the gesture detecting circuit <NUM> side (space mode). The present mode display <NUM> is for example generated by the drawing processing circuit <NUM> on the basis of the switching control signal SW, and displayed in the displayed image.

The present mode display <NUM> is to notify the user whether the electronic pen <NUM> is present within the position detection region DT of the digitizer <NUM> or present within the movement detection spatial region MD of the spatial position detecting device unit <NUM>. The present mode display <NUM> in the example of <FIG> includes: a bar display <NUM> that indicates in which region the electronic pen <NUM> is present by the height of a bar 221B illustrated hatched; and a text display section <NUM> for notifying which region is indicated by the bar display <NUM>.

Incidentally, when the drawing processing circuit <NUM> is supplied with the detection output of the separation distance detecting circuit <NUM> and the coordinate output from the spatial position coordinate correcting circuit <NUM>, the drawing processing circuit <NUM> can recognize the separation distance of the electronic pen <NUM> from the input surface <NUM>, and can therefore make display so as to make the height of the bar in the bar display <NUM> for the position of the electronic pen <NUM> in the present mode display <NUM> correspond to the separation distance of the electronic pen <NUM> from the input surface <NUM>.

<FIG> illustrates a display screen in a case where the electronic pen <NUM> is present within the position detection region DT of the digitizer <NUM> and a rectangular parallelepipedic object OBJ is drawn by the electronic pen <NUM>.

<FIG> illustrates an example of a display image in a case where the user moves the electronic pen <NUM> to the outside of the position detection region DT of the digitizer <NUM> from the state of <FIG>, and performs a gesture operation such as rotates the rectangular parallelepipedic object OBJ as indicated by an arrow AR in <FIG>, for example.

The drawing in the position detection region DT of the digitizer <NUM> and the drawing in the movement detection spatial region MD of the spatial position detecting device unit <NUM> in <FIG> are an example. Drawing processing such as moving the object, applying a pressure to the object, or deforming the object by pulling and stretching a part of the object can be performed as the drawing by the gesture operation.

Incidentally, the electronic pen <NUM> is provided with a pen pressure detecting circuit that detects a pen pressure applied to the pen point when the electronic pen <NUM> is in contact with the input surface <NUM>. Information regarding a result of the detection of the pen pressure detecting circuit is transmitted to the tablet device <NUM>. A fine drawing operation by the electronic pen <NUM> is often performed in a state in which the electronic pen <NUM> is in contact with the input surface <NUM>. Accordingly, the tablet device <NUM> may distinguish the state in which the electronic pen <NUM> is in contact with the input surface <NUM> and the hovering state in which the electronic pen <NUM> is not in contact with the input surface <NUM> on the basis of the information regarding the pen pressure detection result which information is received from the electronic pen <NUM>, and make text display such for example as a "contact state," a "hovering state," or the like on the display screen 201D to notify the operator of the state in which the electronic pen <NUM> is in contact with the input surface <NUM> or the hovering state in which the electronic pen <NUM> is not in contact with the input surface <NUM>.

Incidentally, the tablet device <NUM> includes a control circuit <NUM> formed by a computer, for example, and operates each circuit described above on the basis of control of the control circuit <NUM>. Incidentally, the respective processing of the spatial position coordinate correcting circuit <NUM>, the gesture detecting circuit <NUM>, the separation distance detecting circuit <NUM>, the selection control signal generating circuit <NUM>, and the drawing processing circuit <NUM> can also be configured as software functional sections executed by the control circuit <NUM> by a software program.

The correction information memory <NUM> can store the elements a<NUM> to a<NUM> of the determinant before factory shipment of the tablet device <NUM>. However, in the present embodiment, to be able to make correction including an error of each tablet device <NUM>, the user can store correction information (the elements a<NUM> to a<NUM> of the determinant) in the correction information memory <NUM> before starting the tablet device <NUM> by making the tablet device <NUM> perform correction information generation and storage processing.

A correction information generating circuit <NUM> illustrated in <FIG> is a processing unit for that purpose, and performs correction information generation processing on the basis of control of the control circuit <NUM>. The correction information generating circuit <NUM> can also be provided as an application for the correction information generation and storage processing to the control circuit <NUM>.

At a time of a first start of the tablet device <NUM>, the correction information generating circuit <NUM> is controlled to operate by the control circuit <NUM>. Then, the control circuit <NUM> prompts the user to indicate the positions of at least three points by the electronic pen <NUM> in the position detection region DT of the digitizer <NUM> which region is common to the spatial position detecting device unit <NUM> and the digitizer <NUM>. When the user accordingly indicates the positions of three points or more, detected coordinate information of the digitizer <NUM> and detected coordinate information of the spatial position detecting device unit <NUM> for the three points or more are captured into the correction information generating circuit <NUM>, as described earlier.

Then, the correction information generating circuit <NUM> calculates the elements a<NUM> to a<NUM> of the determinant as described earlier by using the captured coordinate information of the three points or more, and stores the elements a<NUM> to a<NUM> of the determinant in the correction information memory <NUM>.

Incidentally, the calculation of the elements a<NUM> to a<NUM> of the determinant by the correction information generating circuit <NUM> and the processing of storing the elements a<NUM> to a<NUM> of the determinant into the correction information memory <NUM> as described above may of course be set in advance before sale to the user, rather than being performed by the user.

Because the tablet device <NUM> according to the present embodiment is configured as described above, when the electronic pen <NUM> is in contact with the input surface <NUM> of the digitizer <NUM> or is in the hovering state, the digitizer <NUM> detects the position indicated by the electronic pen <NUM>, and the tablet device <NUM> performs fine drawing by line drawing, and when the electronic pen <NUM> is separated by more than the separation distance Lz from the input surface <NUM>, the tablet device <NUM> switches to spatial position detection in the spatial position detecting device unit <NUM>, detects the movement (gesture) of the electronic pen <NUM>, and performs an operation according to the detected movement (gesture).

Hence, the operator can seamlessly perform an operation by gesture from fine drawing merely by spatially moving the electronic pen <NUM> over the tablet device <NUM> without being aware of switching between the digitizer <NUM> and the spatial position detecting device unit <NUM>.

The tablet device <NUM> according to the present embodiment transforms the coordinate output of the digitizer <NUM> into a value in the space coordinate system of the spatial position detecting device unit <NUM>. It is thus possible to prevent the problem of a jump of the cursor position displayed on the display screen according to the detected position of the electronic pen <NUM> even when the space coordinate system is switched.

In addition, the display screen 201D of the display unit <NUM> of the tablet device <NUM> makes display indicating the state in which the digitizer <NUM> is detecting the position indicated by the electronic pen <NUM> or the state in which the spatial position detecting device unit <NUM> is detecting the spatial position of the electronic pen <NUM> according to the separation distance of the electronic pen <NUM> from the input surface <NUM>. Thus, the operator of the electronic pen <NUM> can accurately grasp which operation to perform at the spatial position of the electronic pen <NUM> at a time point in question.

Incidentally, in the description of the foregoing first embodiment, the digitizer <NUM> obtains the separation distance of the electronic pen <NUM> from the input surface <NUM> on the basis of the signal level of the signal received from the electronic pen <NUM>, and generates the switching signal of the switch circuit <NUM> from the obtained separation distance. However, the method of calculating the separation distance of the electronic pen <NUM> from the input surface <NUM> is not limited to the above-described example.

For example, it is also possible for the electronic pen <NUM> to detect the signal level of a signal received from the sensor unit <NUM> of the digitizer <NUM> of the tablet device <NUM> when the electronic pen <NUM> receives the signal, and transmit information regarding the signal level to the tablet device <NUM>. <FIG> is a diagram illustrating an example of a configuration of principal parts of a thus configured electronic pen 1A and a tablet device 2A.

In the present example, the electronic pen 1A includes a received signal level detecting circuit <NUM> that detects the signal level of a signal received from the sensor unit <NUM> of the digitizer <NUM> of the tablet device 2A, and includes a wireless communicating unit <NUM> that performs wireless communication of a Bluetooth (registered trademark) standard, for example. Then, the electronic pen 1A transmits information regarding the signal level of the signal received from the sensor unit <NUM> which signal level is detected by the received signal level detecting circuit <NUM> to the tablet device 2A through the wireless communicating unit <NUM>.

The tablet device 2A includes a wireless communicating unit <NUM> of the Bluetooth (registered trademark) standard for wirelessly communicating with the wireless communicating unit <NUM>, and includes a separation distance detecting circuit <NUM> and a selection control signal generating circuit <NUM> in place of the separation distance detecting circuit <NUM> and the switching signal generating circuit <NUM> in the example of <FIG>. The separation distance detecting circuit <NUM> in the present example detects the separation distance of the electronic pen 1A from the input surface <NUM> of the digitizer <NUM> on the basis of the information regarding the signal level from the electronic pen 1A which information is received by the wireless communicating unit <NUM>, and supplies information regarding the detected separation distance to the selection control signal generating circuit <NUM>.

The selection control signal generating circuit <NUM> generates a selection control signal SEa that performs control so as to select the detection output of the digitizer <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is equal to or smaller than the distance Lz, and select the detection output of the gesture detecting circuit <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is larger than the distance Lz. The selection control signal generating circuit <NUM> performs switching control of the selecting circuit <NUM> by the generated switching control signal SEa.

A configuration of other parts of the tablet device 2A is similar to that illustrated in <FIG>.

According to the configuration of the example of <FIG>, the radio field intensity of the signal transmitted from the sensor unit <NUM> of the digitizer <NUM> to the electronic pen 1A is higher than the radio field intensity of the signal received by the tablet device <NUM> from the electronic pen <NUM>. Therefore, the separation distance detecting circuit <NUM> and the switching signal generating circuit <NUM> of the tablet device 2A can detect the position of the separation distance Lz at the switching point more accurately than in the case of the tablet device <NUM> having the configuration of <FIG>.

In addition, in the above-described example, the separation distance of the electronic pen <NUM> or the electronic pen 1A from the input surface <NUM> of the digitizer <NUM> is detected on the basis of the reception level of the signal between the sensor unit <NUM> of the digitizer <NUM> and the electronic pen <NUM> or the electronic pen 1A. However, the selection control signal of the selecting circuit <NUM> can also be generated from the pen point position of the electronic pen <NUM> which position is detected by the spatial position detecting device unit <NUM>.

<FIG> is a diagram illustrating an example of a configuration of principal parts of a thus configured tablet device 2B. Specifically, the tablet device 2B in the present example includes a separation distance detecting circuit <NUM> and a switching signal generating circuit <NUM> as illustrated in <FIG>, in place of the separation distance detecting circuit <NUM> and the switching signal generating circuit <NUM> in the example of <FIG>. In the present example, the separation distance detecting circuit <NUM> is supplied with the position coordinate output of the spatial position coordinate correcting circuit <NUM>. The separation distance detecting circuit <NUM> detects the spatial position of the electronic pen <NUM> from the position coordinate output of the spatial position coordinate correcting circuit <NUM>, detects the separation distance of the electronic pen 1A from the input surface <NUM> of the digitizer <NUM> from the Z-coordinate of the spatial position of the electronic pen <NUM>, and supplies a resulting detection output to a selection control signal generating circuit <NUM>.

The selection control signal generating circuit <NUM> generates a selection control signal SEb that performs control so as to select the detection output of the digitizer <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is equal to or smaller than the distance Lz, and select the detection output of the gesture detecting circuit <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is larger than the distance Lz. The selection control signal generating circuit <NUM> controls the selecting circuit <NUM> by the generated switching control signal SEb.

In the description of the foregoing embodiment, a gesture is detected on the basis of only changes in the position of the electronic pen <NUM> which position is detected by the spatial position detecting device unit <NUM>. However, a finer gesture operation can be reflected in drawing by providing the electronic pen with a movement detecting sensor that detects the movement of the electronic pen, sending also the detection output of the movement detecting sensor to the tablet device, and referring also to the detection output of the movement detecting sensor in the tablet device.

<FIG> is a diagram illustrating an example of a configuration of principal parts of a thus configured electronic pen 1C and a tablet device 2C. In the example of <FIG>, the electronic pen 1C includes a wireless communicating unit <NUM> similar to that of the modification of <FIG>, and includes a <NUM>-axis sensor <NUM> as a movement detecting sensor of the electronic pen 1C itself. As is well known, the <NUM>-axis sensor <NUM> is a combination of a <NUM>-axis gyro sensor, a <NUM>-axis acceleration sensor, and a <NUM>-axis geomagnetic sensor. The <NUM>-axis sensor <NUM> sends out a <NUM>-axis sensor output with regard to the movement of the electronic pen 1C.

The electronic pen 1C transmits the <NUM>-axis sensor output with regard to the movement of the electronic pen 1C itself which movement is detected by the <NUM>-axis sensor <NUM> to the tablet device 2C through the wireless communicating unit <NUM>.

The tablet device 2C includes a wireless communicating unit <NUM> similar to that of the modification of <FIG>, and includes a pen movement detecting circuit <NUM>. In the tablet device 2C, the wireless communicating unit <NUM> supplies the <NUM>-axis sensor output received from the electronic pen 1C to the pen movement detecting circuit <NUM>. The pen movement detecting circuit <NUM> analyzes the <NUM>-axis sensor output, detects the movement of the electronic pen 1C, and supplies a resulting detection output to a gesture detecting circuit <NUM>'. The gesture detecting circuit <NUM>' detects a gesture made by the operator of the electronic pen 1C by referring to the movement detection output of the electronic pen 1C from the pen movement detecting circuit <NUM> in addition to changes in spatial position coordinates from the spatial position coordinate correcting circuit <NUM>.

A configuration of other parts of the tablet device 2C is similar to that illustrated in <FIG>.

According to the example of <FIG>, the tablet device 2C can finely detect a gesture by the operator of the electronic pen 1C, and can reflect, in drawing, the gesture of a finer movement than conventional.

Incidentally, while in the above example, the tablet device 2C uses the movement detection output of the electronic pen 1C which detection output is detected by the <NUM>-axis sensor <NUM> and received from the electronic pen 1C when the tablet device 2C detects a gesture, the movement detection output of the electronic pen 1C may be used also when the digitizer <NUM> detects the position indicated by the electronic pen 1C. For example, because the inclination of the electronic pen 1C can be detected from the pen movement detection output, it is possible to detect the position indicated by the electronic pen 1C while referring to a result of the detection of the inclination. In addition, the inclination of the electronic pen 1C can also be reflected in the thickness of line drawing.

From a similar idea, in the tablet device <NUM> and the tablet devices 2A to 2C, it is also possible to detect the inclination of the electronic pen <NUM>, the electronic pen 1A, electronic pen 1B, and the electronic pen 1C from a position detection result in the spatial position detecting device unit <NUM> when the digitizer <NUM> detects the position indicated by the electronic pen 1C, and to detect the position indicated by the electronic pen 1C while referring to the inclination.

Incidentally, the movement detection output of the pen movement detecting circuit <NUM> of the tablet device 2C can not only be used to detect a gesture and the position indicated by the electronic pen, but the movement detection output itself can also be reflected in drawing independently. In addition, it is needless to say that the tablet device may detect the movement detection output not only as a drawing operation but also as another input operation.

In the foregoing embodiment, in consideration of a fact that there is a fear of occurrence of an error in a result of electronic pen position detection between the space coordinate system of the digitizer <NUM> and the space coordinate system of the spatial position detecting device unit <NUM>, the coordinate output of the space coordinate system of the spatial position detecting device unit <NUM> is transformed into the coordinate output of the space coordinate system of the digitizer <NUM> so as not to cause a change such that, for example, the display position of the cursor on the display screen 201D jumps when switching is performed between the two coordinate systems.

However, when the cursor position differs at a time of the switching between the two coordinate systems without such a correction being made, the change in the cursor position at the time of the switching can be made inconspicuous by displaying the cursor such that the position of the cursor is gradually changed from the cursor position in the space coordinate system before the switching to the cursor position in the space coordinate system after the switching.

Specifically, as illustrated in <FIG>, for example, in a case where a solid line cursor CS is displayed on the display screen 201D before the switching between the space coordinate systems, and the cursor position after the switching between the space coordinate systems jumps to the position of a broken line cursor CS', the display position is gradually changed from the position of the solid line cursor CS to the position of the broken line cursor CS'. For this purpose, a gradually changing cursor position coordinate Pc is calculated from coordinate position information Pa of the solid line cursor CS and coordinate position information Pb of the broken line cursor CS'.

Specifically, the cursor position coordinate Pc is calculated as Equation <NUM> illustrated in the following. <NUM>] <MAT>.

In (Equation <NUM>), k1 and k2 are weighting coefficients. Specifically, from a time point of the switching at which time point the cursor position coordinate Pc is the coordinate position information Pa of the solid line cursor CS, the value of the weighting coefficient k1 changes so as to decrease gradually from "<NUM>," whereas the value of the weighting coefficient k2 changes so as to increase gradually from "<NUM>.

Then, until a time point at which the position of the cursor CS reaches the position of the broken line cursor CS', the value of the weighting coefficient k1 changes so as to decrease gradually to "<NUM>," and the value of the weighting coefficient k2 is changed so as to increase gradually to "<NUM>.

Consequently, even when the display position is changed from the cursor CS to the cursor CS', the change becomes inconspicuous.

Incidentally, k1 and k2 may be variables k1(t) and k2(t) that change with time t. In this case, from the time point of the switching at which time point the cursor position coordinate Pc is the coordinate position information Pa of the solid line cursor CS, the value of the weighting coefficient k1(t) can be changed so as to decrease gradually from "<NUM>," whereas the value of the weighting coefficient k2(t) can be changed so as to increase gradually from "<NUM>.

In the above description, when the separation distance of the position of the electronic pen from the input surface <NUM> of the digitizer <NUM> exceeds Lz, switching is performed immediately from the detection of the position indicated by the electronic pen by the digitizer <NUM> to the detection of the spatial position of the electronic pen by the spatial position detecting device unit <NUM>. However, in some cases, a state in which the operator has moved the electronic pen from the input surface <NUM> of the digitizer <NUM> of the tablet device to the position of a separation distance equal to or more than Lz may not be a state for gesture input in drawing.

Hence, the detection of the spatial position of the electronic pen by the spatial position detecting device unit <NUM> may not be started immediately when the separation distance from the input surface <NUM> of the digitizer <NUM> exceeds Lz, but may be started when a predetermined start trigger further occurs. Cited as an example of the predetermined start trigger in that case is, for example, sending of operation information of a side switch provided to the electronic pen so as to be operable by the operator to the tablet device through the wireless communicating unit <NUM> when the operator operates the side switch.

Incidentally, not only in a case where the position of the electronic pen (position of the pen point) is moved to a position separated from the input surface of the digitizer but also in a case where the position of the electronic pen (position of the pen point) is moved from a spatial position separated from the input surface of the digitizer such that the distance from the input surface of the digitizer becomes less than Lz, switching may be similarly performed from the space coordinate system of the spatial position detecting device unit to the space coordinate system of the digitizer according to the user operation information of the side switch or the like, for example.

In addition, in a case where the electronic pen includes a <NUM>-axis sensor, the <NUM>-axis sensor may detect a movement of the electronic pen which movement is determined in advance as a movement of the predetermined start trigger, and a result of the detection may be transmitted to the tablet device through the wireless communicating unit <NUM>. In addition, the spatial position detecting device unit <NUM> of the tablet device may detect a gesture based on the movement of the electronic pen, and start a processing operation of detecting a gesture as a target of drawing processing when detecting a gesture based on the movement of the electronic pen which movement is determined in advance as the movement of the predetermined start trigger.

In addition, switching between the space coordinate system of the spatial position detecting device unit and the space coordinate system of the digitizer may be performed according to the movement of the electronic pen which movement is detected by the <NUM>-axis sensor provided to the electronic pen.

In the foregoing embodiment, the tablet device includes a display unit. However, the display unit may be separate from the tablet device, and the tablet device and the display unit may be connected to each other by radio or by wire. It is needless to say that in that case, the input surface <NUM> of the digitizer <NUM> of the tablet device is not the top surface of the display screen of the display unit, but is the top surface of the sensor unit <NUM> of the digitizer <NUM>. In addition, the member on which the spatial position detecting device unit <NUM> is disposed is not limited to the digitizer <NUM>, but the spatial position detecting device unit <NUM> may be disposed on the display unit separate from the digitizer <NUM> or another member.

In addition, the spatial position indication system according to the foregoing embodiment has the configuration of a system including the tablet device and the electronic pen, and the tablet device includes all of the digitizer, the spatial position detecting device unit, and the drawing information generating unit. However, a configuration of the spatial position indication system may be formed by constituting parts other than the digitizer <NUM> and the spatial position detecting device unit <NUM> by a personal computer, for example, and connecting a tablet device having only the functions of the digitizer and the spatial position detecting device unit to the personal computer.

Incidentally, while in the foregoing embodiment, a coordinate value in the space coordinate system of the digitizer <NUM> is transformed into a coordinate value in the spatial position detecting device unit <NUM> in order to correct an error between the two space coordinate systems, a coordinate value in the spatial position detecting device unit <NUM> may be conversely transformed into a coordinate value in the detection region DT of the digitizer <NUM>.

In addition, in the foregoing example, whether the tablet device <NUM> is in a state of the tablet mode or in a state of the space mode is notified to the operator through display on the display screen 201D by the present mode display <NUM>. It is needless to say, however, that the present mode display <NUM> is not limited to the bar display as illustrated in <FIG>. In addition, the present mode may be emitted as a sound from a speaker provided to the tablet device <NUM>.

The display unit in the spatial position indication system according to the present invention can be of a configuration of a head-mounted display, and a 3D drawing space can be a space of virtual reality (which includes virtual reality (VR), mixed reality (MR), augmented reality (AR), and the like, and will hereinafter be abbreviated to VR). <FIG> is a diagram illustrating an outline of a configuration of the whole of a spatial position indication system according to a second embodiment in which a VR space is a 3D drawing space.

Specifically, as illustrated in <FIG>, the spatial position indication system according to the second embodiment includes an electronic pen <NUM>, a digitizer <NUM>, a spatial position detecting unit <NUM>, a space drawing information generating device <NUM>, and a head-mounted display (hereinafter referred to as an HMD) <NUM>.

As with the electronic pen <NUM> according to the first embodiment, an electronic pen of an electromagnetic induction type is used as an example of the electronic pen <NUM> also in the second embodiment. However, the present embodiment is not limited to this. The digitizer <NUM> has a casing <NUM> of a thin rectangular parallelepipedic shape similar to that of the casing of the tablet device <NUM> according to the first embodiment, and has a top surface as an input surface <NUM>. The digitizer <NUM> has a configuration similar to that of the digitizer <NUM> according to the first embodiment. The digitizer <NUM> includes a sensor unit <NUM> and a position detecting circuit <NUM>. The digitizer <NUM> has a position detection region including not only the region of the input surface <NUM> but also a hover region as a spatial region over the input surface <NUM> (which position detection region will hereinafter be referred to as a position detection region DT' (not illustrated) in order to be distinguished from the position detection region DT of the digitizer <NUM> according to the first embodiment) as in the position detection region DT of the digitizer <NUM> according to the first embodiment (see the position detection region DT in <FIG>). Positional information of the electronic pen <NUM> detected in the position detection region DT' in the digitizer <NUM> is supplied to the space drawing information generating device <NUM>.

The spatial position detecting unit <NUM> sets a movement detection target spatial region in which to detect movement of the operator of the electronic pen <NUM>. The spatial position detecting unit <NUM> includes two light emission tracking devices 31A and 31B and a plurality of light position notifying units (hereinafter referred to as trackers) 32A, 32B, 32C, and 32D. Incidentally, in the second embodiment, as will be described later, the HMD <NUM> displays a 3D drawing image drawn in the movement detection target spatial region as a virtual display image. The movement detection target spatial region in the second embodiment will hereinafter be described as a movement detection target spatial region MDv.

The two light emission tracking devices 31A and 31B have an identical configuration. The light emission tracking devices 31A and 31B each include: a laser light emitting unit for infrared laser light; search means for searching within the movement detection target spatial region MDv by emitted infrared laser light; and light position detecting means for detecting light emission of light emitting units of the trackers 32A, 32B, 32C, and 32D receiving the infrared laser light.

The trackers 32A, 32B, 32C, and 32D include: a light receiving sensor that detects the infrared laser light from the light emission tracking devices 31A and 31B; and a light emitting unit formed by an LED, for example, for notifying the light emission tracking devices 31A and 31B of light reception of the infrared laser light by the light receiving sensor when detecting the light reception of the infrared laser light. In the present example, the trackers 32A, 32B, 32C, and 32D are provided with a plurality of light receiving sensors to be able to receive laser light from any direction, and is also provided with a <NUM>-axis sensor, for example, for detecting movement and directions (orientations). The trackers 32A, 32B, 32C, and 32D are attached to objects as targets of position detection within the movement detection target spatial region MDv. Reception output of the light receiving sensors and output of the <NUM>-axis sensor are supplied from each of the trackers 32A, 32B, 32C, and 32D to the space drawing information generating device <NUM> by wire or by radio or via the objects to which the trackers 32A, 32B, 32C, and 32D are attached.

The light emission tracking devices 31A and 31B control the laser light emitting units by the search means, and make a search by emitting infrared laser light so as to perform search and scanning within the movement detection target spatial region MDv to detect tracker positions. Each of the trackers 32A, 32B, 32C, and 32D monitors for light reception of the infrared laser light by the sensor, and lights the light emitting unit formed by an LED when the sensor detects light reception of the infrared laser light. The light emission tracking devices 31A and 31B detect the positions of the objects to which the trackers 32A, 32B, 32C, and 32D are fitted within the movement detection target spatial region MDv by detecting light emission of the light emitting units of the trackers 32A, 32B, 32C, and 32D. The light emission tracking devices 31A and 31B are configured to be able to detect also elapsed times from light emission times of the emitted infrared lasers to time points of detection of the light emission of the light emitting units of the trackers 32A, 32B, 32C, and 32D when detecting the light emission.

The two light emission tracking devices 31A and 31B are connected to the space drawing information generating device <NUM> by wire or by radio, and notifies the space drawing information generating device <NUM> of space position information of the detected trackers in the movement detection target spatial region MDv.

The objects to which the trackers 32A, 32B, 32C, and 32D are fitted in the present embodiment are a dedicated unit <NUM> for a glove (glove unit) that the operator wears in the present example as illustrated in <FIG> as well as the electronic pen <NUM> and the digitizer <NUM>. The trackers are attached to the electronic pen <NUM>, the digitizer <NUM>, and the glove unit <NUM>, respectively. Specifically, in the present example, the tracker 32A and the tracker 32B are fitted to an upper left corner and a lower right corner of a casing of the digitizer <NUM> in a thin rectangular parallelepipedic shape to be able to notify the position of the digitizer <NUM>. In addition, the tracker 32C is fitted to the electronic pen <NUM> to notify the position of the electronic pen <NUM> and notify the movement of the electronic pen <NUM>. Further, the tracker 32D is fitted to the glove unit <NUM> to notify the position of a hand of the operator and notify the movement of the hand.

The space drawing information generating device <NUM> is formed by a personal computer, for example, and processing thereof is performed by a program for space drawing information generation. The space drawing information generating device <NUM> performs switching processing so as to handle a coordinate value of a position indicated by the electronic pen <NUM> seamlessly when the position indicated by the electronic pen <NUM> moves from the position detection region DT of the digitizer <NUM> to the movement detection target spatial region MD of the spatial position detecting unit <NUM> or when the position indicated by the electronic pen <NUM> moves from the movement detection target spatial region MD to the position detection region DT. In addition, processing of transforming the coordinate value of the position indicated by the electronic pen <NUM> may be performed along with the switching. An outline of main processing functions in the space drawing information generating device <NUM> will be described with reference to <FIG>.

<FIG> is a diagram illustratively illustrating a case where the position of the pen point of the electronic pen <NUM> moves from the movement detection target spatial region MD outside the position detection region DT of the digitizer <NUM> to the inside of the position detection region DT of the digitizer <NUM>. The spatial position detecting unit <NUM> detects the position of the pen point of the electronic pen <NUM> as position coordinates Av1, Av2, Av3,. , AvN in a three-dimensional coordinate space (Xv, Yv, Zv) of the spatial position detecting unit <NUM>, and supplies the position coordinates to the space drawing information generating device <NUM>.

As for the positions Av2 and Av3 at which the position of the pen point of the electronic pen <NUM> is present within the position detection region DT of the digitizer <NUM>, the digitizer <NUM> also detects the pen point position of the electronic pen <NUM> as position coordinates At2, At3,. in a three-dimensional coordinate space (X, Y, Z) of the digitizer <NUM> as illustrated in <FIG>, and supplies the position coordinates to the space drawing information generating device <NUM>.

As illustrated in <FIG>, the space drawing information generating device <NUM> outputs position information Aout of the pen point of the electronic pen <NUM> by switching from the position information detected by the spatial position detecting unit <NUM> to the position information detected by the digitizer <NUM> when the pen point position of the electronic pen <NUM> comes into the position detection region DT of the digitizer <NUM>.

The space drawing information generating device <NUM> in the present example changes the position coordinates Av1, AV2, Av3,. of the pen point of the electronic pen <NUM> which position coordinates are detected by the spatial position detecting unit <NUM> into coordinates f(Av1), f(AV2), f(Av3),. , f(AvN) (f denotes mapping from the movement detection target spatial region MD to the position detection region DT) transformed so as to be able to be handled in common by the digitizer <NUM> as in the first embodiment described above.

Here, the processing of coordinate transformation between the space coordinate system of the position detection region DT of the digitizer <NUM> and the space coordinate system of the movement detection spatial region MD can be performed by using offset values in which a difference between the origin positions of the two space coordinate systems is taken into consideration when the respective directions of an Xv-axis, a Yv-axis, and a Zv-axis are same directions as the respective directions of an X-axis, a Y-axis, and a Z-axis as in the foregoing. In addition, in a case where the respective directions of the X-axis, the Y-axis, and the Z-axis are different from the respective directions of the Xv-axis, the Yv-axis, and the Zv-axis, the coordinate transformation can be performed by performing linear transformation using, for example, the determinant illustrated in Equation <NUM> or the like as in the foregoing first embodiment.

In the case of <FIG>, f(Av1), f(AV2), f(Av3),. , f(AvN) can be used as the position information output Aout of the pen point of the electronic pen <NUM> in the space drawing information generating device <NUM> when the pen point of the electronic pen <NUM> moves. At the position coordinates Av2 and Av3, it suffices to use the position information detected by the digitizer <NUM>, and the position coordinates Av2 and Av3 are At2 and At3, respectively.

Hence, the position information output Aout of the pen point of the electronic pen <NUM> is expressed as<MAT>.

Hence, the space drawing information generating device <NUM> can seamlessly handle the pen point position of the electronic pen <NUM> even in a case where the movement trajectory of the pen point of the electronic pen <NUM> straddles the inside of the position detection region DT in which the digitizer <NUM> can detect the pen point position of the electronic pen <NUM> and a region on the outside of the position detection region DT in which region only the spatial position detecting unit <NUM> can detect the pen point position.

<FIG> illustrates an example of a configuration in which processing functions performed by the space drawing information generating device <NUM> in the second embodiment are illustrated as a configuration of functional blocks. Incidentally, in <FIG>, each functional block is referred to as a "circuit" for convenience.

In the space drawing information generating device <NUM>, detection output of the position indicated by the electronic pen <NUM> from the position detecting circuit <NUM> of the digitizer <NUM> is supplied as one input of a selecting circuit <NUM> to the selecting circuit <NUM>.

The space position information of each of the trackers 32A to 32D from the two light emission tracking devices 31A and 31B of the spatial position detecting unit <NUM> is supplied to a spatial position detecting circuit <NUM> of the space drawing information generating device <NUM>. In addition, though not illustrated, as described earlier, the reception output of the light receiving sensors and the output of the <NUM>-axis sensor from each of the trackers 32A, 32B, 32C, and 32D are also supplied to the spatial position detecting circuit <NUM>. The spatial position detecting circuit <NUM> detects also directions in which the trackers 32A, 32B, 32C, and 32D are oriented from these pieces of information. The tracker 32C is attached to the electronic pen <NUM> in a state in which the tracker 32C is in specific directional relation and positional relation to the pen point position. Thus, the spatial position detecting circuit <NUM> detects the pen point position of the electronic pen <NUM> from the position and direction of the detected tracker 32C.

The spatial position detecting circuit <NUM> sets a spatial region on three coordinate axes (set as Xs, Ys, and Zs for convenience also in the present example), that is, the movement detection target spatial region MDv as a spatial region in which the spatial position detecting unit <NUM> can detect the positions of the trackers 32A to 32D. The spatial position detecting circuit <NUM> detects the spatial position coordinates of the digitizer <NUM>, the electronic pen <NUM>, and the glove unit <NUM> on the three axes Xs, Ys, and Zs from the space position information of each of the trackers 32A to 32D from the two light emission tracking devices 31A and 31B.

Hence, in the spatial position indication system according to the second embodiment, the whole of the position detection region DT' of the digitizer <NUM> is included within the movement detection target spatial region MDv of the spatial position detecting unit <NUM>. In the present embodiment, the digitizer <NUM> is installed within the movement detection target spatial region MDv with the position of the digitizer <NUM> fixed within the movement detection target spatial region MDv. That is, the position detection region DT' of the digitizer <NUM> is included as a fixed region within the movement detection target spatial region MDv in the spatial position detecting circuit <NUM>. That is, the movement detection target spatial region MDv of the spatial position detecting circuit <NUM> includes the position detection region DT' of the digitizer <NUM> as a common region.

Supposing that the attachment positions of the tracker 32A and 32B attached to the digitizer <NUM> are accurate, it suffices to adjust an origin position offset between the coordinate system (X, Y, Z) of the position detection region DT of the digitizer <NUM> and the coordinate system (Xs, Ys, Zs) of the movement detection spatial region MD' of the spatial position detecting circuit <NUM>.

However, in the present embodiment, in consideration of a fear of occurrence of an error in accuracy between the coordinate system (X, Y, Z) of the position detection region DT' of the digitizer <NUM> and the coordinate system (Xs, Ys, Zs) of the movement detection target spatial region MDv of the spatial position detecting circuit <NUM>, the spatial position detecting circuit <NUM> has functions of the spatial position coordinate correcting circuit <NUM> described in the first embodiment. Then, also in the second embodiment, a correction information memory <NUM> is provided which stores the elements a<NUM> to a<NUM> of the determinant illustrated in <FIG>, the elements being obtained as in the correction information memory <NUM> in the first embodiment.

The spatial position detecting circuit <NUM> calculates the determinant of (Equation <NUM>) using the elements a<NUM> to a<NUM> of the determinant from the correction information memory <NUM>, and supplies the spatial position coordinate output of the trackers 32A to 32D to a gesture detecting circuit <NUM>.

The gesture detecting circuit <NUM> detects the movement (gesture) of the electronic pen <NUM> and the movement of the glove unit <NUM> on the basis of the coordinate output from the spatial position detecting circuit <NUM>, and supplies a resulting detection output as another input signal of the selecting circuit <NUM>.

In the second embodiment, as in the first embodiment, the position detecting circuit <NUM> of the digitizer <NUM> supplies information regarding the signal level of a signal received from the electronic pen <NUM> to a separation distance detecting circuit <NUM> of the space drawing information generating device <NUM>. The separation distance detecting circuit <NUM> detects a separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> from the signal level of the signal received from the electronic pen <NUM>. The separation distance detecting circuit <NUM> then supplies information regarding the detected separation distance to a selection control signal generating circuit <NUM>.

The selection control signal generating circuit <NUM> generates a selection control signal SE' that controls the selecting circuit <NUM> so as to select the detection output of the position detecting circuit <NUM> of the digitizer <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is equal to or smaller than the distance Lz at which the above-described hovering state can be detected, and controls the selecting circuit <NUM> so as to select the detection output of the gesture detecting circuit <NUM> when the separation distance of the pen point of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM> is larger than the distance Lz. The selection control signal generating circuit <NUM> controls the selecting circuit <NUM> by the generated switching control signal SE'. The selection control signal generating circuit <NUM> supplies the switching control signal SE' also to a drawing information generating circuit <NUM>.

The selecting circuit <NUM> selects either the one input or the other input according to the selection control signal SW', and supplies the input to the drawing information generating circuit <NUM>.

The drawing information generating circuit <NUM> generates drawing information corresponding to operation of the electronic pen <NUM> for drawing by the operator of the electronic pen <NUM> within the movement detection target spatial region MDv. In the second embodiment, the operation of the electronic pen <NUM> for drawing by the operator of the electronic pen <NUM> includes an operation of positioning the electronic pen <NUM> within the position detection region DT' of the digitizer <NUM> and performing indicated position input by the electronic pen <NUM> and an operation of positioning the electronic pen <NUM> outside the position detection region DT' of the digitizer <NUM> within the movement detection target spatial region MDv and making a gesture for drawing by moving the electronic pen <NUM>.

When the electronic pen <NUM> is positioned within the position detection region DT' of the digitizer <NUM>, the separation distance detecting circuit <NUM> detects that the electronic pen <NUM> is positioned within the position detection region DT' of the digitizer <NUM>. On the basis of a resulting detection output, the selection control signal generating circuit <NUM> generates the selection control signal SE' that controls the selecting circuit <NUM> so as to select the detection output of the position detecting circuit <NUM> of the digitizer <NUM>. Hence, the detection output of the position indicated by the electronic pen <NUM> from the position detecting circuit <NUM> of the digitizer <NUM> is supplied to the drawing information generating circuit <NUM> through the selecting circuit <NUM>.

The drawing information generating circuit <NUM> performs drawing processing using, as line drawing input, the received detection output of the position indicated by the electronic pen <NUM>, and generates a fine 3D drawing image.

In addition, when the electronic pen <NUM> is positioned outside the position detection region DT' of the digitizer <NUM> within the movement detection target spatial region MDv, the separation distance detecting circuit <NUM> detects that the electronic pen <NUM> is positioned outside the position detection region DT' of the digitizer <NUM> within the movement detection target spatial region MDv. On the basis of a resulting detection output, the switching signal generating circuit <NUM> generates the selection control signal SE' that controls the selecting circuit <NUM> so as to select the detection output of the gesture detecting circuit <NUM>. Hence, gesture information based on the movement detection output of the electronic pen <NUM> and the glove unit <NUM> from the gesture detecting circuit <NUM> is supplied to the drawing information generating circuit <NUM> through the selecting circuit <NUM>.

The drawing information generating circuit <NUM> performs 3D drawing processing based on the received gesture information. That is, the drawing processing is performed according to the movement of the electronic pen <NUM> and the movement of the glove unit <NUM> worn by the operator, the movement of the electronic pen <NUM> and the movement of the glove unit <NUM> being detected by the gesture detecting circuit <NUM>.

In this case, the drawing information generating circuit <NUM> determines whether to perform drawing processing using the detection output of the position indicated by the electronic pen <NUM> as line drawing input or whether to perform drawing processing based on the gesture information according to the selection control signal SE' of the selecting circuit <NUM>.

Drawing image information generated by the drawing information generating circuit <NUM> as described above is supplied to the HMD <NUM> through a display drive circuit <NUM>, and is displayed as a virtual image on a display image formed by an LCD, for example.

Hence, a remarkable effect is produced in that the operator can seamlessly perform drawing by a gesture from fine drawing merely by spatially moving the electronic pen <NUM> without being aware of switching between position detection in the digitizer <NUM> and position detection (movement detection) in the spatial position detecting unit <NUM>.

In this case, in the second embodiment, the drawing information generating circuit <NUM> includes a unit that generates a virtual space image to be displayed on the HMD <NUM>, and is able to draw a drawing image by the operator of the electronic pen <NUM> on the virtual space image. The position of a virtual object included in the virtual space image can be determined in advance within the movement detection target spatial region MDv. When the operator performs an operation of touching the virtual object included in the virtual space image by the glove unit <NUM>, the drawing information generating circuit <NUM> can detect the operation on the basis of the gesture information from the gesture detecting circuit <NUM>. When the operator performs the operation of touching the virtual object included in the virtual space image by the glove unit <NUM>, the drawing information generating circuit <NUM> outputs a resulting detection output to a tactile sensation producing information generating unit <NUM>.

When the tactile sensation producing information generating unit <NUM> receives the detection output of the operation of touching the virtual object included in the virtual space image by the operator from the drawing information generating circuit <NUM>, the tactile sensation producing information generating unit <NUM> supplies the glove unit <NUM> with tactile sensation producing information that produces a tactile sensation. The glove unit <NUM> includes a tactile sensation producing device that performs vibration or the like on the basis of the tactile sensation producing information. The tactile sensation producing device is driven to notify the operator that the virtual object is virtually touched.

Incidentally, the drawing information generating circuit <NUM> generates the drawing image information to be output so as to display, on the display screen of the HMD <NUM>, a state in which the digitizer <NUM> is detecting the position indicated by the electronic pen <NUM> or in a state in which the spatial position detecting unit <NUM> is detecting the spatial position of the electronic pen <NUM> according to the separation distance of the electronic pen <NUM> from the input surface <NUM> of the digitizer <NUM>. Hence, the operator of the electronic pen <NUM> can accurately grasp which drawing operation to perform at the spatial position of the electronic pen <NUM> at a present time.

Incidentally, the foregoing modifications of the first embodiment are applicable also in the second embodiment. It is needless to say that in the second embodiment, the second modification uses the spatial position detecting unit <NUM> and the spatial position detecting circuit <NUM> in place of the spatial position detecting device unit <NUM>.

In the foregoing second embodiment, the spatial position detecting unit <NUM> has a configuration including the light emission tracking devices emitting infrared laser light and the trackers. However, it is needless to say that the spatial position detecting unit <NUM> is not limited to this configuration. For example, a configuration using another invisible light sensor, a visible light sensor, or a combination thereof may also be adopted. In addition, the spatial position detecting unit <NUM> may be configured to raise the critical height position by increasing the frequency of an electromagnetic wave emitted from the digitizer <NUM>, and detect the spatial position of the electronic pen <NUM>. That is, it suffices for the spatial position detecting unit <NUM> to normally detect the position of the electronic pen <NUM> in the input surface of the digitizer <NUM> and the hover region at a first frequency, and switch to a second frequency higher than the first frequency and detect the spatial position of the electronic pen <NUM> at a second critical height position higher than a first critical height position at the first frequency.

In addition, a configuration may be adopted in which the electronic pen is provided with a battery and provided with radio wave transmitting and receiving means, a radio wave is externally transmitted to the electronic pen, and the spatial position of the electronic pen is used by receiving a radio wave from the electronic pen. In addition, a configuration using magnetic resonance, radio waves, or ultrasonic waves, or the like may be adopted. In addition, target objects whose spatial positions are to be detected (the electronic pen and the tablet) may be photographed by one or a plurality of cameras, and the spatial positions of the target objects may be detected by using the photographed images.

Incidentally, in the foregoing second embodiment, the operator of the electronic pen <NUM> wears the HMD <NUM>, and therefore cannot directly see the digitizer <NUM>. Accordingly, a virtual image of the digitizer <NUM> can be drawn in the virtual space image displayed on the HMD <NUM> so that the operator recognizes the position of the digitizer <NUM> on the display screen of the HMD <NUM>. In addition, the HMD may of course support augmented reality (AR), so that the digitizer <NUM> can be seen directly. In addition, while the glove unit <NUM> and the electronic pen <NUM> are configured separately from each other, the glove unit <NUM> and the electronic pen <NUM> may be combined with each other.

In addition, the means for displaying a three-dimensional image is not limited to the HMD, but may use glasses (spectacles), a 3D display, contact lenses, an aerial imaging (AI) plate, and further a hologram technology or the like. In addition, the digitizer <NUM> may be provided with a display such for example as an LCD or the like, and 3D display may be made on the display. These display means may be used together with the HMD so that a person other than the wearer of the HMD views a drawing image displayed on the HMD.

Incidentally, as for coordinate transformation, in the second embodiment, the coordinate value of the pen point of the electronic pen which coordinate value is detected by the spatial position detecting unit <NUM> is transformed into a coordinate value in the coordinate system in the digitizer <NUM>. Conversely, however, the coordinate value of the pen point of the electronic pen which coordinate value is detected by the digitizer <NUM> may be transformed into a coordinate value in the coordinate system in the spatial position detecting unit <NUM>.

In addition, in the foregoing example, the separation distance of the pen point position of the electronic pen <NUM> from the input surface of the digitizer <NUM> is detected on the basis of the reception level of the signal between the sensor unit <NUM> of the digitizer <NUM> and the electronic pen <NUM>. However, the method of detecting the separation distance between the pen point position of the electronic pen <NUM> and the input surface of the digitizer <NUM> is not limited to this.

For example, in the second embodiment, the spatial position detecting unit <NUM> can detect the pen point position of the electronic pen and the position of the input surface of the digitizer <NUM>. Thus, the separation distance between the pen point position of the electronic pen <NUM> and the input surface of the digitizer <NUM> may be detected from the detected pen point position of the electronic pen <NUM> and the detected position of the input surface of the digitizer <NUM>, and the selection control signal of the selecting circuit <NUM> may be generated.

Incidentally, in the description of the foregoing embodiments, a gesture based on the movement of the electronic pen is detected in the spatial region outside the position detection region DT or DT' of the digitizer as an example of the indicated position detecting device unit. However, the position indicated by the electronic pen on the basis of the movement of the pen point of the electronic pen, rather than the movement of the electronic pen, can be detected also in the outside spatial region.

Incidentally, in the foregoing embodiment, when the position of the electronic pen moves from the inside of the position detection region DT or DT' of the digitizer as an example of the indicated position detecting device unit to the spatial region outside the position detection region DT or DT', the drawing processing circuit <NUM> and the drawing information generating circuit <NUM> immediately perform drawing processing according to a gesture based on movement detection in the movement detection spatial region MD or the movement detection target spatial region MDv. However, the operator does not necessarily move the electronic pen from the inside of the position detection region DT or DT' of the digitizer to the spatial region outside the position detection region DT or DT' in order to make a gesture for drawing, but may thus move the electronic pen simply to stop drawing operation input.

In consideration of this, the drawing processing circuit <NUM> and the drawing information generating circuit <NUM> can also be configured to perform drawing processing according to a gesture based on movement detection in the movement detection spatial region MD or the movement detection target spatial region MDv when the position of the electronic pen moves from the inside of the position detection region DT or DT' of the digitizer as an example of the indicated position detecting device unit to the spatial region outside the position detection region DT or DT', and when a further predetermined trigger event is detected.

Incidentally, in that case, the selecting circuit <NUM> and the selecting circuit <NUM> may be selection-controlled when the position of the electronic pen moves from the inside of the position detection region DT or DT' of the digitizer as an example of the indicated position detecting device unit to the spatial region outside the position detection region DT or DT', or may be selection-controlled when the further trigger event is detected. Incidentally, the position of the electronic pen <NUM> is of course detected immediately by the digitizer <NUM> and the digitizer <NUM> when the position of the electronic pen moves to the inside of the position detection region DT or DT' of the digitizer as an example of the indicated position detecting device unit from the spatial region outside the position detection region DT or DT'.

Specifically, for example, the drawing processing circuit <NUM> and the drawing information generating circuit <NUM> are configured to perform drawing processing according to a gesture based on movement detection in the movement detection spatial region MD or the movement detection target spatial region MDv only when the operator moves the position of the electronic pen from the inside of the position detection region DT or DT' of the digitizer as an example of the indicated position detecting device unit to the spatial region outside the position detection region DT or DT', and the operator further operates the side switch mounted on the electronic pen as the predetermined trigger event.

The predetermined trigger event is not limited to the operation of the side switch. For example, the predetermined trigger event may be a specific gesture of the operator of the electronic pen. Alternatively, the predetermined trigger event may be a voice instruction of the operator. In a case where a voice instruction is set as the predetermined trigger event, a microphone is provided to the tablet device <NUM> in the first embodiment, and a microphone is provided to the space drawing information generating device in the second embodiment. A voice collected by the microphone is subjected to voice recognition, and whether the voice is the specific trigger event of the operator is determined. Alternatively, a microphone may be provided to the electronic pen, and collected voice information may be sent out through the wireless communicating unit included in the electronic pen, received by the wireless communicating unit included in the tablet device <NUM> or the space drawing information generating device, and subjected to voice recognition.

In the foregoing first embodiment and the foregoing second embodiment, an electronic pen and a digitizer of an electromagnetic induction type are used. However, the electronic pen and the digitizer are not limited to this, but an electronic pen and a digitizer of a capacitive type (including an active capacitive coupling type and a passive capacitive coupling type) can of course be used.

In addition, the tablet device <NUM> according to the first embodiment and the digitizer according to the second embodiment may be a portable mobile telephone terminal referred to as what is called a smart phone, and may be a personal computer provided with a digitizer.

Incidentally, the above description has been made of a case where 3D drawing is performed by the spatial position indication system. However, drawing images as a target of the present invention may be 2D drawing images and <NUM>. 5D drawing images.

Claim 1:
A spatial position indication system comprising:
an indicated position detecting device unit (<NUM>) configured to detect a first position of an electronic pen (<NUM>) at an input surface for receiving instruction input by the electronic pen (<NUM>) and a hover region over the input surface,
wherein a position detection region (DT), in which the first position indicated by the electronic pen (<NUM>) can be detected by the indicated position detecting device unit (<NUM>), includes the input surface (<NUM>) and the hover region;
wherein the spatial position indication system further comprises
a spatial position detecting device unit (<NUM>) configured to detect a second position of the electronic pen (<NUM>) in a spatial region (MD) including at least a part of the hover region; and
a selecting unit configured to select whether to use the first position as the instruction input or use the second position as the instruction input according to a separation distance of the electronic pen (<NUM>) from the input surface,
wherein the spatial position indication system further comprises:
a transforming unit configured to perform transformation from detected coordinates (X, Y, Z) of the first position in the space coordinate system of the position detection region (DT) to detected coordinates (Xs, Ys, Zs) of the second position in the space coordinate system of the spatial region (MD), or
a transforming unit configured to perform transformation from detected coordinates (Xs, Ys, Zs) of the second position in the space coordinate system of the spatial region (MD) to detected coordinates (X, Y, Z) of the first position in the space coordinate system of the position detection region (DT),
wherein the space coordinate system of the spatial region (MD) of the spatial position detecting device unit (<NUM>) is set independently of the space coordinate system of the position detection region (DT) of the indicated position detecting device unit (<NUM>),
wherein the spatial position indication system further comprises:
a drawing image control unit configured to control a drawing image displayed on a display unit on a basis of detection output of the position indicated by the electronic pen (<NUM>) from the indicated position detecting device unit (<NUM>) and spatial position detection output from the spatial position detecting device.