Position detection device and control method for position detection sensor

Abstract

[Project] To provide a location detection device capable of meeting requirements such as waterproof specifications, avoiding complexity in manufacturing processes, and miniaturizing portable information terminals, while also saving power consumption. [Solution] A planar shape coil (160) is positioned so that it is close to the storage portion of an electronic pen, and its central axis direction is in a direction that intersects the axis direction of the electronic pen stored in the storage portion, and among the generated magnetic flux, the number of magnetic fluxes that intersect in opposite directions with respect to the position detection coil of the electronic pen is not equal. By means of a first control means, the supply of a signal to the planar shape coil (160) and the reception of a signal through the planar shape coil by electromagnetic induction are controlled to be performed alternately. By means of a first detection means, the state of insertion / removal of the electronic pen from the storage portion is detected according to the presence or absence of a signal received through the planar shape coil (160).

Description

Technology Field

[0001] The present invention relates to a position detection device equipped with a so-called position detection sensor and used as an input device for various information terminals, and a method for controlling the position detection sensor used in the position detection device. Background Technology

[0002] Many portable information terminals equipped with so-called touch panels, such as high-performance mobile phones called smartphones and tablet PCs (Personal Computers), are being provided. A touch panel is an electronic component that combines a display device, such as a liquid crystal display, with a position detection device equipped with a position detection sensor or a position detection circuit, enabling various operational inputs through touch operations by a user's finger or similar body.

[0003] Position detection sensors (hereinafter simply referred to as sensors) include capacitive and electromagnetic induction types. The capacitive method detects the position of an indicator by detecting changes in capacitance between multiple conductive wires provided on the indicator and the sensor. Since the indicator is the user's finger, touch input via the finger is possible. Furthermore, the electromagnetic induction method detects the indicated position by the electronic pen by transmitting and receiving signals via electromagnetic induction between a dedicated electronic pen (position indicator) containing a resonant circuit composed of an inductor element (coil) and a capacitor element (condenser) and a loop coil group provided on the sensor side. Because a dedicated electronic pen is used, precise input is possible, and input of information based on pen pressure is also possible through the pen's pressure detection function.

[0004] In addition, there are portable information terminals equipped with so-called hybrid sensors that feature both capacitive and inductive sensors, capable of supporting both input by a user's finger and delicate input by a dedicated electronic pen. In portable information terminals equipped with such hybrid sensors, simple operations are generally performed via touch input using the user's finger. Therefore, keeping the inductive sensor constantly running is undesirable as it accelerates battery drainage.

[0005] Therefore, in a portable information terminal equipped with a hybrid sensor, a storage compartment for an electronic pen is provided in the housing, and when the electronic pen is stored in this compartment, the electromagnetic induction sensor is disabled. In other words, when the electronic pen is stored in the compartment, only the capacitive sensor is activated. On the other hand, when the electronic pen is not stored in the compartment, at least the electromagnetic induction sensor is activated. By doing so, the electromagnetic induction sensor can be activated only when the electronic pen is in use, thereby contributing to saving battery power consumption.

[0006] Conventionally, detection of whether an electronic pen is stored in a storage compartment of an electronic pen provided in a portable information terminal is performed by a so-called mechanical switch, for example, as shown in Fig. 2 of Patent Document 1 described later. In addition, it is also performed to detect whether an electronic pen is stored in a storage compartment by equipping the electronic pen with a magnet and providing a magnetic sensor composed of a Hall element in the portable information terminal. Prior art literature

[0007] Japanese Special Publication No. 10-013893 The problem to be solved

[0008] In recent years, there has been a demand to make portable information terminals and electronic pens waterproof so that they can withstand use outdoors on rainy days or near bodies of water such as seas, rivers, and lakes. However, if a mechanical switch is provided in the storage compartment of the electronic pen of the portable information terminal to detect whether the aforementioned electronic pen is stored, it is difficult to make it waterproof because a gap is created in the moving part of the switch. Furthermore, if a magnet is provided in the electronic pen and a magnetic sensor is provided on the portable information terminal side, it is undesirable because the magnet mounted on the electronic pen may affect the resonance circuit of the electronic pen or the circuit on the sensor side for position detection, or the circuit on the portable information terminal side may affect the magnetic sensor.

[0009] Thus, a method can be devised in which a coil is placed in the storage portion of the electronic pen to cover the coil embedded in the electronic pen, and whether the electronic pen is stored is detected by electromagnetic induction. That is, as shown in FIG. 10(A), a storage portion (203) of an electronic pen having an opening (202) is provided in the housing of a portable information terminal (200) equipped with a touch panel (201), and a coil (204) is provided in the inner wall of the storage portion (203) at a position that covers the coil embedded in the electronic pen when the electronic pen is stored.

[0010] In addition, a case can be considered in which an electronic pen (300) is stored in the storage portion (203) of the electronic pen. In this case, as indicated by the arrow in FIG. 10(B), the electronic pen (300) is inserted into the inner side of the coil (204) placed in the storage portion (203), and the coil (204) covers the coil (301) of the electronic pen (300). Then, a signal is transmitted from the coil (204) for a certain period, and a signal is received from the coil (301), which is a component of the resonant circuit of the electronic pen (300), for a certain period thereafter. In this case, if the transmitted signal from the electronic pen (300) can be received, it can be detected that the electronic pen is stored in the storage portion (203).

[0011] However, as shown in FIG. 10(A), providing a coil (204) on the inner wall of the storage portion (203) of the electronic pen of the portable information terminal (200) may complicate the manufacturing process or increase the thickness of the portable information terminal. It is desirable for the manufacturing process to be as simple as possible, and in recent years, there has been a demand to make the portable information terminal thinner, so it must be possible to meet the demand for thinness.

[0012] In light of the above, the present invention aims to provide a position detection device and a control method for a position detection sensor suitable for application to a portable information terminal, which can achieve waterproof specifications, avoid complexity in the manufacturing process, enable further thinning of the portable information terminal, and enable saving of power consumption. means of solving the problem

[0013] To solve the above problem, the position detection device of the invention described in claim 1 is,

[0014] A position detection device having a storage portion for housing an electronic pen having a position indicating coil wound in the axial direction,

[0015] A planar coil positioned in close proximity to the storage portion, wherein the central axis direction is a direction that intersects the axis direction of the electronic pen stored in the storage portion, and the planar coil positioned at a location where the number of magnetic fluxes that intersect in opposite directions with respect to the position indicator coil of the electronic pen among the generated magnetic fluxes is not equal;

[0016] A first control means for controlling the alternating execution of supplying a signal to the above-mentioned planar coil and receiving a signal through the above-mentioned planar coil by electromagnetic induction, and

[0017] It is characterized by having a first detection means for detecting the state of insertion / removal of the electronic pen in the storage portion depending on the presence or absence of a signal received through the above-mentioned planar coil.

[0018] According to the position detection device of the invention described in claim 1, a storage unit is provided for housing an electronic pen having a position indicating coil wound in the axial direction, and a planar coil is disposed in proximity to the storage unit. The central axis direction of the planar coil is a direction that intersects the axial direction of the electronic pen stored in the storage unit, and is disposed at a position where the number of magnetic fluxes that intersect in opposite directions with respect to the position indicating coil of the electronic pen stored in the storage unit among the generated magnetic fluxes is not equal. By doing so, efficient transmission and reception of signals can be performed between the position indicating coil of the electronic pen stored in the storage unit and the planar coil provided in the position detection device.

[0019] Then, by means of the first control means, the supply of a signal to the corresponding planar shape coil and the reception of a signal through the corresponding planar shape coil by electromagnetic induction are alternately executed. When an electronic pen is stored in the storage compartment, the transmission and reception of a signal is performed by electromagnetic induction between the corresponding planar shape coil and the position indicator coil of the electronic pen stored in the storage compartment. Accordingly, by means of the first detection means, the state of insertion / removal of the electronic pen into or out of the storage compartment, that is, whether the electronic pen is stored in the storage compartment, is detected based on the presence or absence of a signal received through the corresponding planar shape coil.

[0020] By this, it is possible to properly detect whether an electronic pen is stored in the storage compartment of an electronic device without providing a mechanical switch, a magnetic sensor, or a coil formed on a spiral shape in the storage compartment. Furthermore, since a planar coil is used, it is easy to comply with waterproof specifications, thereby avoiding complexity in the manufacturing process and enabling the miniaturization of portable information terminals. Specifically, although the planar coil is formed by winding a coated wire on a substrate, since it is planar, reliable waterproofing can be easily achieved by covering the front surface of the planar coil with a resin that does not shield signals, for example using resist technology. Moreover, even with waterproofing, the thickness of the planar coil portion does not increase significantly. Additionally, if the electromagnetic induction sensor that detects the indicated position by the electronic pen is configured to operate only when the electronic pen, which is likely to be used, is not stored in the storage compartment, it can contribute to saving power consumption in the electronic device equipped with this position detection device. Effects of the invention

[0021] According to the present invention, by using a planar coil, it is possible to realize a position detection device suitable for use in a portable information terminal and a control method for a position detection sensor, which enables the realization of waterproof specifications, avoidance of complexity in the manufacturing process, and thinning of the portable information terminal, as well as saving power consumption. Brief explanation of the drawing

[0022] FIG. 1 is a diagram illustrating an example of an electronic device configured using an input device consisting of a position detection device and an electronic pen related to the invention. FIG. 2 is a figure for explaining an example of the configuration of an electronic pen used in an embodiment. FIG. 3 is a block diagram showing a schematic configuration of an electronic pen used in an embodiment and an example of a circuit configuration of a position detection device of a first embodiment. Figure 4 is a figure for explaining the positional relationship between a planar coil and the coil of an electronic pen, and the magnetic flux generated by the planar coil. Figure 5 is a figure for explaining in more detail the positional relationship between the coil of an electronic pen stored in a storage unit and the planar coil. FIG. 6 is a flowchart for explaining the processing executed by the processing control unit of the position detection device of the first embodiment. FIG. 7 is a block diagram showing a schematic configuration of an electronic pen used in an embodiment and a circuit configuration example of a position detection device in a second embodiment. FIG. 8 is a flowchart for explaining the processing executed by the processing control unit of the position detection device of the second embodiment. FIG. 9 is a block diagram showing a schematic configuration of an electronic pen used in an embodiment and a circuit configuration example of a position detection device in a third embodiment. FIG. 10 is a diagram illustrating an example of a conventional detection mechanism that detects whether an electronic pen is stored in a storage compartment. Specific details for implementing the invention

[0023] Hereinafter, an embodiment of the apparatus and method of the present invention will be described with reference to the drawings.

[0024] [First Embodiment]

[0025] [Specific examples of electronic devices]

[0026] Referring to FIG. 1, an example of an electronic device configured to be equipped with an input device comprising a position detection device related to the present invention and an electronic pen (pen-type position indicator) used for said position detection device will be described. The electronic device of this example is, for example, a tablet PC or high-function mobile phone terminal equipped with a display device such as an LCD (Liquid Crystal Display), and is composed of an electronic device body (1) equipped with a position detection device and an electronic pen (2).

[0027] The electronic device body (1) is configured such that an LCD, two position detection sensors with different detection methods, a motherboard, etc. are stacked (overlappingly arranged) between the housing (1A) and the front panel (1F). In this embodiment, the two position detection sensors with different detection methods are, one is an electromagnetic induction type position detection sensor and the other is a capacitive type position detection sensor.

[0028] An opening (1FW) is provided in the front panel (1F). The opening (1FW) is set to the same size as the display area of ​​the LCD display screen and the operation area for receiving input from a user using an electronic pen (2). Additionally, the housing (1A) of the electronic device body (1) is provided with a storage portion (11) for storing the electronic pen (2) described later, and when the electronic pen (2) is not in use, the electronic pen (2) is stored in the storage portion (11).

[0029] The electronic pen (2) is used for inputting information through an electromagnetic induction type position detection sensor. The user, as needed, takes out the electronic pen (2) stored in the storage unit (11) and performs position indication operations on the operation area (1FW). The electronic pen (2) is suitable for use when inputting fine information, such as inputting shapes or pictures, for example.

[0030] In addition, the electronic device body (1) is equipped with a capacitive position detection sensor, and by touching a finger to the operation area (1FW), the user can perform operations such as drawing, inputting handwritten characters, or selecting icons or display buttons.

[0031] And, it is said that operation is performed by an electronic pen (2) on the operation area (1FW) of the electronic device body (1). In this case, the position and pressure of operation performed by the electronic pen (2) are detected by an electromagnetic induction type position detection sensor provided inside the electronic device body (1), and accordingly, the display light control circuit (microcomputer) of the electronic device body (1) controls the display processing on the LCD display screen.

[0032] Likewise, in the case of the electronic device, it is said that operation is performed by a user's finger, etc. on the operation area (1FW) of the electronic device body (1). In this case, the position indicated by the finger, etc. is detected by a capacitive position detection sensor provided inside the electronic device body (1), and accordingly, the display light control circuit of the electronic device body (1) controls the display processing on the LCD display screen.

[0033] As described above, the electronic pen (2) functions as an electromagnetic induction type position detection sensor, and although details will be described later, it is equipped with a coil (21) and a capacitor (capacitor element) that form a resonant circuit. The coil (21) transmits and receives signals between itself and the position detection sensor and is a position indicator coil. In addition, in the case of the electronic device body (1) of this embodiment, as shown in FIG. 1, a flat-shaped coil (160) is provided near the coil (21) embedded in the electronic pen (2) when the electronic pen (2) is stored in the lower side of the storage portion (11).

[0034] By transmitting and receiving signals by electromagnetic induction between the planar shape coil (160) and the coil (21) of the electronic pen (2), the state of insertion / removal from the storage portion (11) of the electronic pen (2) can be detected depending on whether there is a transmission signal from the coil (21) of the electronic pen (2). That is, it is possible to detect whether the electronic pen is stored in the storage portion (11) or not. Furthermore, when the electronic pen (2) is stored in the storage portion (11), the position of the electronic pen (2) is not detected using an electromagnetic induction type position detection sensor, thereby enabling the realization of saving power consumption in the main body (1) of the electronic device.

[0035] In addition, by using a flat coil (160), the state of insertion / removal of the electronic pen into the storage unit (11) can be easily prevented from creating a gap compared to the case where a mechanical switch is provided to detect the state, making it easy to make it waterproof. Also, unlike the case where a magnetic sensor is provided near the storage unit (11) and a magnet is mounted on the electronic pen to detect the state of insertion / removal of the electronic pen into the storage unit (11), there is no concern that the magnet will affect the position detection sensor, etc. Furthermore, compared to the case where a spiral coil is provided in the storage unit (11) to detect the state of insertion / removal of the electronic pen into the storage unit (11), the manufacturing process can be simplified, and it can also contribute to making the electronic device body (1) thinner.

[0036] [Example of Electronic Pen Composition]

[0037] Next, an example of the configuration of an electronic pen (2) that performs position indication on an electromagnetic induction type position detection sensor mounted on the main body (1) of the electronic device shown in FIG. 1 will be described. FIG. 2 is a diagram for explaining an example of the configuration of the electronic pen (2) of this embodiment, FIG. 2(A) shows a cross-sectional view of the electronic pen (2), and FIG. 2(B) shows an equivalent circuit of the electronic pen (2).

[0038] As shown in FIG. 2, the electronic pen (2) is configured with various components mounted within the housing (23) to realize the electronic pen function. The ferrite core (22) is formed, for example, in a cylindrical ferrite material, with an axial through hole of a predetermined diameter (e.g., diameter = 1 mm) formed by a rod-shaped core (24) formed by a resin, etc., formed at a position including the centerline in the axial direction, for inserting and passing through the rod-shaped core (24).

[0039] A core body (24) is inserted into the through hole of the ferrite core (22) so as to penetrate the ferrite core (22). That is, the core body (24) is longer than the length in the axial direction of the ferrite core (22). In addition, the portion of the core body (24) inserted into the corresponding through hole of the ferrite core (22) has a diameter slightly shorter than the diameter of the corresponding through hole, so that it can slide axially within the corresponding through hole. Furthermore, the end portion of the core body (24) that becomes the pen tip has a diameter longer than the diameter of the through hole of the ferrite core (22), and the tip is machined into a hemispherical shape so that it can move smoothly on an operating surface such as a touch panel.

[0040] And, as shown in FIG. 2(A), a portion of a predetermined length including the center of the axial direction of the ferrite core (22) becomes a coil-wound portion where the coil (21) is wound along the axial direction, and the portions on both sides become coil-unwound portions where the coil is not wound. That is, when viewing the ferrite core (22) in its axial direction, the portion from the pen end side end to the pen end side end of the coil-wound portion becomes a first coil-unwound portion where the coil is not wound, and the portion from the other end of the coil-wound portion to the end opposite to the pen end side of the ferrite core (22) becomes a second coil-unwound portion where the coil (21) is not wound.

[0041] The extension lines (conductor lines) (21a, 21b) from both ends of the coil (21) wound on the ferrite core (22) extend into the inside of the housing (23) to the printed circuit board (26) described later, and are connected to a capacitor (Cf) provided on the printed circuit board (26). By doing so, a resonant circuit is formed by the coil (21) and the capacitor (Cf) on the printed circuit board (26), and signals can be transmitted and received between the coil (21) and the position detection device of the electromagnetic induction method described later by electromagnetic induction.

[0042] And, on the side opposite to the pen tip of the core body (24), a connection part (25) is provided, consisting of a mold part (25A), a pressure detection part (25B), a fitting part (25C), and a connection terminal part (25D). This connection part (25) is a part that integrally connects the part on the pen tip side, which consists of the coil (21), the ferrite core (22), and the core body (24), with the printed circuit board (26) and the circuit board protection pipe (27) described later. The mold part (25A) is a part formed in a cylindrical shape by resin, etc., and the outer circumference of the cross-section on the ferrite core (22) side of the mold part (25A) is slightly larger than the outer circumference of the coil winding part of the ferrite core (22). And, on the cross-section side facing the ferrite core (22) of the mold part (25A), a concave part is provided to fit the second coil non-winding part of the ferrite core (22).

[0043] Additionally, as shown in FIG. 2(A), a core retaining part (A1), a conductive rubber (A2), a ring spacer (A3), a dielectric (A4), and a terminal member (A5) are provided inside the mold part (25A). Each of these parts is fitted by the mold part (25A) and the fitting part (25C) described later to become a pressure detection part (25B) that detects pressure.

[0044] Specifically, the core body retaining part (A1) is formed in a cup shape, for example, by hard rubber, and the end portion opposite to the pen tip side of the core body (24) is inserted and retained. The bottom portion of the core body retaining part (A1) opposite to the core body (24) is formed in a spherical shape. Furthermore, the core body retaining part (A1) functions as a pressure part that presses the conductive rubber (A2) according to the writing pressure applied to the core body (24).

[0045] The conductive rubber (A2) has a predetermined thickness and is of the same shape and size as the opposing surface of the dielectric (A4). The pen tip side surface of the conductive rubber (A2) faces the bottom surface formed in a spherical shape of the core retainer (A1), and the other side faces one surface of the dielectric (A4) through the ring spacer (A3).

[0046] The ring spacer (A3) is a member formed in a ring shape, and a gap equal to the thickness of the ring spacer (A3) is provided between the conductive rubber (A2) and the pen tip side surface of the dielectric (A4) to separate the two. The dielectric (A4) is formed by a material in which dielectric properties are superior to conductivity, such as ceramic, and acts as an insulator that does not conduct electricity with respect to DC voltage. On the other side of the dielectric (A4), a terminal member (A5) having a predetermined area is attached and provided. In this way, the conductive rubber (first electrode) (A2) and the terminal member (second electrode) (A5) form a variable capacitance capacitor by having the dielectric (A4) in between.

[0047] That is, depending on the pressure applied to the tip of the core (24), the core (24) slides up and down in the axial direction. In conjunction with this, the core holding part (A1) pushes the conductive rubber (A2) up or down. Since a gap is provided between the conductive rubber (A2) and the dielectric (A4) by the ring spacer (A3), the conductive rubber (A2) approaches and contacts the dielectric (A4) according to the pressure applied to the core (24), and changes the contact area. As a result, the capacitance between the conductive rubber (A2) and the terminal member (A5) with the dielectric (A4) in between changes according to the pressure. Also, when no pressure is applied, the conductive rubber (A2) separates from the dielectric (A4) due to the presence of the ring spacer (A3).

[0048] And, the conductive wire connected to the conductive rubber (A2) and the conductive wire connected to the terminal member (A5) are connected, for example, to the terminal of the connection terminal part (25D) described later through the outside of the mold part (25A) and the fitting part (25C), and are connected to the electronic circuit of the printed circuit board (26) described later through the terminal of the connection terminal part (25D). By this, the pressure applied to the core body (24) in the electronic circuit part of the printed circuit board (26) can be detected as a change in the capacitance of the variable capacitance capacitor configured as described above.

[0049] In this example, the pressure detection unit (25B), which is composed of a core holding part (A1), a conductive rubber (A2), a ring spacer (A3), a dielectric (A4), and a terminal member (A5), is, for example, the same as the pressure detection means of a known configuration described in Japanese Patent Publication No. 5-275283. In addition, the pressure detection unit (25B) may be configured to be the same as the pressure detection means of a known configuration described in Japanese Patent Publication No. 2011-186803. In addition, for example, it may be configured using a semiconductor element that varies capacitance according to pressure, as disclosed in Japanese Patent Publication No. 2013-161307.

[0050] The fitting portion (25C) is a part that fits with the substrate protection pipe (27) described later. The fitting portion (25C) is formed in a roughly cylindrical shape, for example, by resin or hard rubber, and is firmly fitted with the mold portion (25A) to form an integral part. As a result, as described above, the core retaining portion (A1), conductive rubber (A2), ring spacer (A3), dielectric (A4), and terminal member (A5) are fitted into the mold portion (25A) and the fitting portion (25C), and the pressure detection portion (25B) composed of these members is stably maintained within the housing (23).

[0051] Additionally, a recess is provided on the inner side of the fitting portion (25C) to which the leading edge of the printed circuit board (26), which will be described later, is fitted. Furthermore, the outer diameter of the fitting portion (25C) is slightly longer than the inner diameter of the substrate protection pipe (27), so that it can be fitted firmly with the substrate protection pipe (27). When the substrate protection pipe (27) is fitted into the fitting portion (25C), the outer circumference of the substrate protection pipe (27) aligns with the outer circumference of the fitting portion (25C) or the mold portion (25A).

[0052] As shown in FIG. 2(A), the connection terminal portion (25D) is a portion consisting of two upper and lower plates connected to the fitting portion (25C). This plate portion is configured to have a printed circuit board (26), which will be described later, placed between them. In this case, the gap between the two upper and lower plates is slightly narrower than the thickness of the printed circuit board (26), so that the printed circuit board (26) can be held.

[0053] And, on one of these two plates, for example, the upper plate in FIG. 2(A), a terminal connected to the conductive rubber (A2) described above and a conductive line from the terminal member (A5) is provided so that it extends from the upper surface to the lower surface by drawing the cross-section of the circuit board side. By this, when a printed circuit board (26) is inserted into the connection terminal part (25D), it is automatically connected to the terminal part of the electronic circuit provided on the printed circuit board (26).

[0054] A printed circuit board (26) is formed on a rectangular insulating substrate in which terminals to the aforementioned electronic circuit or various circuit components constituting the electronic circuit are mounted, and wiring for connecting them is provided. Various circuit components include an IC (Integrated Circuit) that functions as a control circuit, a plurality of capacitors (Cf), etc. As shown in FIG. 2(A), the printed circuit board (26) is housed and protected inside a substrate protection pipe (27).

[0055] The substrate protection pipe (27) is formed using metal, carbon material, synthetic resin, etc., and is a hard tube-shaped member that is difficult to fold or bend. The substrate protection pipe (27) has a core-side opening and a rear-side opening at both ends. These core-side opening and rear-side opening are openings in a direction intersecting the axial direction. Then, a fitting part (25C) of the connection part (25) is fitted into a predetermined range of the inner side of the substrate protection pipe (27) from the core-side opening, and the two are fitted together. Likewise, a pipe cover (28) is fitted into a predetermined range of the inner side of the substrate protection pipe (27) from the rear-side opening, and the two are fitted together. This pipe cover (28) is also provided with a concave part into which the end of the printed circuit board (26) is fitted.

[0056] By this, the part of the pen end where the core (24) is inserted into the ferrite core (22) on which the coil (21) is wound, the connection part (25), the substrate protection pipe (27) that houses the printed circuit board (26), and the pipe cover (28) are integrally connected and housed within the housing (23) to form an electronic pen (2).

[0057] And, the equivalent circuit of the electronic pen (2) of this embodiment is shown in FIG. 2(B). That is, a coil (21), a pressure detection unit (25B) composed of a variable capacitance capacitor, and a capacitor (Cf) on a printed circuit board (26) are connected in parallel to form a resonant circuit. By doing so, it becomes possible to transmit and receive signals with a position detection device equipped with an electromagnetic induction type position detection sensor, which will be described later.

[0058] In addition, the electronic pen (2) of this embodiment can transmit and receive signals by electromagnetic induction between a flat coil (160) provided near a storage portion (11) in which the electronic pen (2) of the electronic device body (1) is stored. By doing so, the electronic device body (1) can appropriately detect whether the electronic pen (2) is stored in the storage portion (11), and, as described above, when the electronic pen (2) is stored in the storage portion (11), it is possible to control the position so that the detection of the indicated position by the electromagnetic induction type position detection device is not performed.

[0059] [Overview of Electromagnetic Induction Coordinate Detection Sensor]

[0060] Next, an example of a circuit configuration of an embodiment of an electromagnetic induction type position detection device (100) that performs detection (detection) of an indication position and pen pressure using an electromagnetic induction type electronic pen (2) described with reference to FIG. 2 will be described. FIG. 3 is a block diagram showing a schematic configuration of an electronic pen (2) and an example of a circuit configuration of a position detection device (100). As described above, an electromagnetic induction type position detection device and an electrostatic coupling type position detection device are mounted on the main body (1) of an electronic device, but the position detection device (100) shown in FIG. 3 is mounted on the main body (1) of an electronic device as an electromagnetic induction type position detection device.

[0061] As explained using FIG. 2(A), the electronic pen (2) has a pen tip in which a core body (24) is passed through a through hole provided along the axis at a position including the axis of a ferrite core (22) in which a coil (21) is wound. Also, as explained using FIG. 2(A) and (B), the coil (21) of the electronic pen (2) is connected to a capacitor (Cf) of a pressure detection unit (25B) or a printed circuit board (26) to form a resonant circuit.

[0062] Meanwhile, the position detection device (100) consists of a position detection circuit unit (main sensor unit) that detects the indicated position by the electronic pen (2) and the pen pressure applied to the electronic pen (2), and a insertion sensor circuit unit (sub sensor unit) that detects whether the electronic pen (2) is stored in the storage unit (11). First, the configuration of the position detection circuit unit will be explained.

[0063] The position detection circuit is equipped with a position detection sensor (110) which is a main sensor. The position detection sensor (110) is configured by stacking an X-axis direction loop coil group (111) and a Y-axis direction loop coil group (112). Each loop coil group (111, 112) is composed of, for example, at least 40 square loop coils each. Each loop coil constituting each loop coil group (111, 112) is arranged to be sequentially overlapped in parallel at equal intervals.

[0064] A position detection sensor (110) composed of loop coil groups (111, 112) is connected to a circuit comprising a receiving amplifier (AP), an oscillation circuit (120), a position detection circuit (130), a pressure detection circuit (140), and a processing control unit (150) through a selection circuit (113) and a switch circuit (SW1). An X-axis direction loop coil group (111) and a Y-axis direction loop coil group (112) are connected to the selection circuit (113). The selection circuit (113) is configured to select any loop coil among the two loop coil groups (111, 112) under the control of the processing control unit (150) described later.

[0065] The oscillation circuit section (120) consists of an oscillator (121) and a current driver (122). The oscillator (121) generates an alternating current signal of frequency f0 and supplies it to the current driver (122) and the synchronous detector (141) of the pressure detection circuit section (140) described later. The current driver (122) converts the alternating current signal supplied from the oscillator (121) into current and transmits it to the switch circuit (SW1). The switch circuit (SW1) switches the connection points (transmitting terminal (T), receiving terminal (R)) to which the loop coil selected by the selection circuit (113) is connected, under control from the processing control section (150) described later. Among these connection points, the current driver (122) is connected to the transmitting terminal (T), and the receiving amplifier (AP) is connected to the receiving terminal (R).

[0066] The induced voltage generated in the loop coil selected by the selection circuit (113) (received signal from the electronic pen (2)) is transmitted to the receiving amplifier (AP) through the selection circuit (113) and the switch circuit (SW1). The receiving amplifier (AP) amplifies the induced voltage supplied from the loop coil and transmits it to the detector (131) of the position detection circuit (130) and the synchronous detector (141) of the pressure detection circuit (140).

[0067] The detector (131) of the position detection circuit (130) detects the induced voltage generated in the loop coil, i.e., the received signal, and transmits it to the low-pass filter (132). The low-pass filter (132) has a cutoff frequency sufficiently lower than the frequency f0 and converts the output signal of the detector (131) into a DC signal and transmits it to the sample-hold circuit (133). The sample-hold circuit (133) maintains the voltage value at a predetermined timing of the output signal of the low-pass filter (132), specifically at a predetermined timing during the reception period, and transmits it to the A / D (Analog to Digital) conversion circuit (134). The A / D conversion circuit (134) converts the analog output of the sample-hold circuit (133) into a digital signal and transmits it to the processing control unit (150).

[0068] Meanwhile, the synchronous detector (141) of the pressure detection circuit (140) synchronously detects the output signal of the receiving amplifier (AP) as an AC signal from the oscillator (121) and transmits a signal of a level corresponding to the phase difference between them to the low-pass filter (142). This low-pass filter (142) has a cutoff frequency sufficiently lower than frequency f0 and converts the output signal of the synchronous detector (141) into a DC signal and transmits it to the sample hold circuit (143). This sample hold circuit (143) maintains the voltage value at a predetermined timing of the output signal of the low-pass filter (142) and transmits it to the A / D conversion circuit (144). The A / D conversion circuit (144) converts the analog output of the sample hold circuit (143) into a digital signal and transmits it to the processing control unit (150).

[0069] The processing control unit (150) controls each part constituting the position detection circuit unit (main sensor circuit unit) and the insertion / discharge sensor circuit unit (sub sensor unit) described later. That is, the processing control unit (150) controls the selection of the loop coil in the selection circuit (113), the switching of the switch circuit (SW1), and the timing of the sample hold circuit (133, 143). Based on the input signal from the A / D conversion circuit (134, 144), the processing control unit (150) transmits a signal (electromagnetic induction signal) from the X-axis direction loop coil group (111) and the Y-axis direction loop coil group (112) at a constant transmission duration.

[0070] In each loop coil of the X-axis direction loop coil group (111) and the Y-axis direction loop coil group (112), an induced voltage is generated by a signal transmitted from the electronic pen (2). The processing control unit (150) calculates the coordinate values ​​of the X-axis direction and Y-axis direction indication positions of the electronic pen (2) based on the voltage values ​​of the induced voltage generated in each loop coil. Additionally, the processing control unit (150) detects pen pressure based on the phase difference between the transmitted signal and the received signal.

[0071] Next, the configuration of the insertion sensor circuit section (sub-sensor section) is described. As described above, a planar coil (160), which is a sub-sensor, is provided near the storage section (11) of the electronic pen (2). One end of this planar coil (160) is connected to the oscillation circuit section (120) or ground through a switch circuit (SW2). In addition, the other end of the planar coil (160) is connected to a sample hold circuit (170), and the output from the sample hold circuit (170) is supplied to the processing control section (150).

[0072] Additionally, the switch circuit (SW2) and the sample hold circuit (170) are controlled by a control signal from the processing control unit (150). The processing control unit (150) forms a control signal that alternately sets the transmission period and the reception period. Here, the transmission period is the period during which current from the oscillation circuit unit (120) is supplied to the planar shape coil (160) to induce an induced voltage in the coil (21) of the electronic pen (2) by electromagnetic induction, and the period during which the control signal from the processing control unit (150) is turned on (high level). Furthermore, the reception period is the period during which current from the capacitor (Cf) is supplied to the coil (21) of the electronic pen (2) to detect the induced voltage (reception signal) generated in the planar shape coil (160) by electromagnetic induction, and the period during which the control signal from the processing control unit (150) is turned off (low level).

[0073] In this way, the processing control unit (150) forms a control signal that is turned on during the transmission period and turned off during the reception period, and supplies this to the sample hold circuit (170) through the switch circuit (SW2) and the inversion circuit (IV). Accordingly, when the control signal that turns on is supplied to the switch circuit (SW2), the control signal that turns off is supplied to the sample hold circuit (170). Conversely, when the control signal that turns off is supplied to the switch circuit (SW2), the control signal that turns on is supplied to the sample hold circuit (170).

[0074] By this, the switch circuit (SW2) is switched to the terminal (Ta) side during the transmission period when the control signal from the processing control unit (150) is turned on, and current from the oscillation circuit unit (120) is supplied to the planar coil (160). Meanwhile, the sample hold circuit (170) is supplied with a control signal that turns off by the function of the inversion circuit (IV) during the transmission period when the control signal from the processing control unit (150) is turned on, so it does not operate during this period and is grounded to a ground not shown.

[0075] Therefore, during the transmission period, since magnetic flux is generated by current flowing through the planar coil (160), if the coil (21) of the electronic pen (2) is located near the planar coil (160), current flows through the coil (21), and an induced voltage is generated at both ends. That is, by electromagnetic induction, the transmission of a signal from the planar coil (160) to the coil (21) of the electronic pen (2) is performed. In the electronic pen (2), since a resonant circuit is formed by the coil (21) and the capacitor (Cf), an electric charge corresponding to the induced voltage is accumulated in the capacitor (Cf).

[0076] Additionally, during the receiving period when the control signal from the processing control unit (150) is turned off, the switch circuit (SW2) is switched to the terminal (Ra) side, and one end of the planar coil (160) is grounded to ground. In this case, during the transmitting period when the control signal from the processing control unit (150) is turned off, the sample hold circuit (170) is supplied with a control signal that turns on by the function of the inversion circuit (IV), and operates during this period.

[0077] As described above, during the transmission period, charge is accumulated in the capacitor (Cf) that constitutes the resonant circuit of the electronic pen (2). During the reception period, the charge accumulated in the capacitor (Cf) causes current to flow through the coil (21) of the electronic pen (2), thereby generating magnetic flux. Because of this, the magnetic flux generated by the coil (21) of the electronic pen (2) acts to cause current to flow through the planar coil (160) located near the coil (21) of the electronic pen (2), and an induced voltage is generated at both ends thereof. That is, by electromagnetic induction, the transmission of a signal from the coil (21) of the electronic pen (2) to the planar coil (160) is performed. The sample hold circuit (170) samples the induced voltage generated at both ends of the planar coil (160) during the reception period, maintains the voltage value, and transmits it to the processing control unit (150).

[0078] By this, if the voltage from the sample hold circuit (170) is above a certain value, it can be seen that a signal is transmitted and received by electromagnetic induction between the flat shape coil (160) and the coil (21) of the electronic pen (2). In this case, the processing control unit (150) can detect that the electronic pen (2) is stored in the storage unit (11). Conversely, if the voltage from the sample hold circuit (170) is below a certain value, it can be seen that a signal is not transmitted and received by electromagnetic induction between the flat shape coil (160) and the coil (21) of the electronic pen (2). In this case, the processing control unit (150) can detect that the electronic pen (2) is not stored in the storage unit (11).

[0079] And, when the processing control unit (150) detects that the electronic pen (2) is stored in the storage unit (11), it controls each unit so that the detection processing of the indicated position and pen pressure through the position detection sensor (110) is not performed. Conversely, when the processing control unit (150) detects that the electronic pen (2) is not stored in the storage unit (11), it controls each unit so that the detection processing of the indicated position and pen pressure through the position detection sensor (110) is performed. By doing this, the position detection sensor (110) is not driven when unnecessary, thereby saving power consumption.

[0080] [Positional relationship between the electronic pen coil and the planar coil]

[0081] FIG. 4 is a diagram for explaining the positional relationship between the planar coil (160) and the coil (21) of the electronic pen (2), and the magnetic field and magnetic flux generated by the planar coil (160). As previously described, the coil (21) embedded in the electronic pen (2) is wound along the axis direction indicated by the dotted line on FIG. 4 (A) and (B). In addition, the planar coil (160) provided near the storage portion (11) that houses the electronic pen (2) is provided near the coil (21) of the electronic pen (2) housed in the storage portion (11), so as to be nearly parallel to the axis of the electronic pen (2), as shown in FIG. 4 (A) and (B).

[0082] As shown in FIG. 4, the set of magnetic flux for the magnetic field generated by current flowing in the direction of the arrow through the wires (Ca1, Ca2) located on the short side (Ca) of the planar coil (160) is represented by the symbol Mfa. Likewise, the set of magnetic flux for the magnetic field generated by current flowing in the direction of the arrow through the wires (Cb1, Cb2) located on the short side (Cb) of the planar coil (160) is represented by the symbol Mfb.

[0083] Then, when the electronic pen (2) is stored in the storage portion (11) of the housing (1A), a planar coil (160) is positioned near the coil (21) of the electronic pen (2). In this case, the magnetic flux (Mfa, Mfb) generated by the planar coil (160) links with the coil (21) of the electronic pen (2), thereby inducing current in the coil (21) and accumulating charge in the capacitor (Cf) connected thereto. Here, linkage means that the magnetic flux (Mfa, Mfb) penetrates the coil (21) like a chain.

[0084] However, as shown in FIG. 4(A), with respect to the center of the axial direction (direction indicated by the dotted line in FIG. 4(A)) of the coil (21) equipped with the electronic pen (2), it is said that the number of magnetic fluxes (Mfa) linking the right part of the coil (21) and the number of magnetic fluxes (Mfb) linking the left part of the coil (21) are equal. As shown in FIG. 4(A), the magnetic fluxes (Mfa) and (Mfb) have reversed directions in which they interact with the coil (21) of the electronic pen (2) (the direction in which the magnetic fluxes (Mfa, Mfb) link the coil (21)).

[0085] That is, the magnetic flux (Mfa) generated to the right and the magnetic flux (Mfb) generated to the left by the planar coil (160) each act to cause currents that are opposite to each other in the coil (21) of the electronic pen (2). Because of this, the current generated by electromagnetic induction in the coil (21) of the electronic pen (2) is canceled out, so current does not flow efficiently in the coil (21) and a state is created where sufficient charge cannot be stored in the capacitor (Cf).

[0086] Therefore, in this case, even if current is not supplied to the flat-shaped coil (160), since no charge is accumulated in the capacitor (Cf) of the electronic pen (2), no current flows through the coil (21) of the electronic pen (2), and no magnetic field (magnetic flux) is generated in the coil (21). Because of this, no current flows through the flat-shaped coil (160) according to the magnetic flux generated in the coil (21) of the electronic pen (2), and even if the electronic pen (2) is stored in the storage part (11), this cannot be detected.

[0087] Therefore, in this embodiment, regarding the coil (21) of the electronic pen (2) stored in the storage unit (11), one of the magnetic flux (Mfa) generated in the right part of the planar coil (160) and the magnetic flux (Mfb) generated in the left part is made to link more. For example, as shown in FIG. 4(B), regarding the coil (21) of the electronic pen (2) stored in the storage unit (11), the planar coil (160) is shifted to the right so that the magnetic flux (Mfb) generated on the left side of the planar coil (160) links more with the coil (21) of the electronic pen (2). By doing so, according to the magnetic flux (Mfb) generated on the left side of the planar coil (160), current can be efficiently generated in the coil (21) of the electronic pen (2) by electromagnetic induction, and sufficient charge can be stored in the capacitor (Cf).

[0088] Of course, contrary to the case of FIG. 4(B), the planar coil (160) may be shifted to the left with respect to the coil (21) of the electronic pen (2) stored in the storage unit (11), so that the magnetic flux (Mfa) generated on the right side of the planar coil (160) links more with the coil (21) of the electronic pen (2). In addition, in this case, since there is a possibility that the magnetic flux (Mfb) generated on the left side of the planar coil (160) may interfere with other parts of the electronic pen (2), it is necessary to take this into consideration.

[0089] In addition, in this embodiment, as shown in FIG. 4(C), the planar coil (160) is composed of a flexible printed circuit (FPC). Specifically, the planar coil (160) is formed by attaching a coil formed on a planar surface using a conductive metal, such as copper, onto a thin, soft base film (171) having insulating properties, such as polyimide. By doing so, each turn of the coil can be fixed on the same plane so that it does not fall up and down (in the direction of the central axis) or become misaligned on the plane.

[0090] In addition, a magnetic metal plate (172) and a conductive metal shield (173) are provided on the lower side in the direction of the central axis of the planar coil (160). The magnetic metal plate (172) increases the magnetic flux generated by the planar coil (160), and in the example shown in FIG. 4, it acts to efficiently raise the magnetic flux from the lower side in the direction of the axis of the planar coil (160) to the upper side. The conductive metal shield (173) is intended to prevent electromagnetic waves arriving from the outside from affecting the planar coil (160). In this way, in this embodiment, signals can be efficiently transmitted and received by electromagnetic induction between the coil (21) of the electronic pen (2) stored in the storage unit (11) and the planar coil (160).

[0091] FIG. 5 is a diagram for explaining in more detail the positional relationship between the coil (21) of the electronic pen (2) stored in the storage portion (11) and the planar coil (160) in this embodiment. As shown in FIG. 5, the width of the area where the planar coil (160) is formed is, for example, 6 mm or more, such that the coil (21) of the electronic pen (2) can be positioned inside the planar coil (160).

[0092] And, it is said that the electronic pen (2) passes over the planar coil (160) in the longitudinal direction of the planar coil (160), and the tip (pen tip) of the core body (24) of the electronic pen (2) is positioned at a location corresponding to the end (Tb) of the planar coil (160). In this case, with respect to the center of the axial direction of the coil (21) of the electronic pen (2), we consider the case where the number of magnetic fluxes (Mfa, Mfb) generated by the planar coil (160) is equal and intersects in the half of the coil (21) on the pen tip side and the half on the side opposite to the pen tip side, as shown in FIG. 4(A).

[0093] In this case, as shown in FIG. 5, the position of the electronic pen (2) stored in the storage unit (11) is positioned such that it is at least 1 mm away from the end (Tb) of the planar coil (160) toward the other end. By shifting it by more than 1 mm from the end (Tb) of the planar coil (160) in this way, the coil (21) of the electronic pen (2) can be made to link more magnetic flux (Mfb), as in the example shown in FIG. 4(B). By doing so, current can be efficiently generated in the coil (21) of the electronic pen (2) by electromagnetic induction according to the magnetic flux generated by the planar coil (160).

[0094] And, as shown in FIG. 5, a rectangular area (160Ar) with a vertical length of 6 mm or more is formed by adding the length (L1) from the end (Tb) of the planar coil (160) to the point where the tip of the core (24) of the electronic pen (2) is located, and the length (L2) which is 30 mm or more away from the tip of the core (24) of the electronic pen (2) to the rear end of the electronic pen (2), and is formed as an area for providing a magnetic metal plate or a conductive metal shield. Accordingly, in the example shown in FIG. 5, at least a rectangular area (160Ar) with a vertical length of 6 mm or more and a horizontal length of 31 mm or more is formed as an area for providing a planar coil (160) and an area for providing a magnetic metal plate or a conductive metal shield.

[0095] And, if the positional relationship between the planar coil (160) and the coil (21) of the electronic pen (2) is such that it is as shown in FIG. 5, then signals can be efficiently transmitted and received by electromagnetic induction between the planar coil (160) and the coil (21) of the electronic pen (2). In addition, how far the tip of the core (24) of the electronic pen (2) is separated from the end (Tb) of the planar coil (160) can be determined, for example, by finding a position where signals can be efficiently transmitted and received by electromagnetic induction through experiment.

[0096] [Specific example of control in the position detection device (100)]

[0097] Next, a specific example of processing control by the processing control unit (150) of the position detection device (100) having the configuration described using FIG. 3 will be described. FIG. 6 is a flowchart for explaining processing executed by the processing control unit (150) of the position detection device (100) after the main power of the electronic device body (1) is turned on. The processing of the flowchart shown in FIG. 6 is to which the "method for controlling a position detection sensor" of the invention related to the present application is applied.

[0098] The processing control unit (150) first performs a storage detection process to detect whether the electronic pen (2) is stored in the storage unit (11) using a sub-sensor, a planar shape coil (160) (step S101). Specifically, the processing control unit (150) forms a control signal that alternately repeats an on period and an off period, and supplies this to the sample hold circuit (170) through the switch circuit (SW2) and the inversion circuit (IV). By doing so, control signals with opposite phases are supplied to each of the switch circuit (SW2) and the sample hold circuit (170).

[0099] Accordingly, when a control signal that turns on is supplied to the switch circuit (SW2), a control signal that turns off is supplied to the sample hold circuit (170). In this case, the switch circuit (SW2) is switched to the terminal (Ta) side, and the sample hold circuit (170) becomes non-operational and grounded to ground. Because of this, current from the oscillation circuit (120) is supplied to the planar coil (160), magnetic flux is generated in the planar coil (160), and current flows to the coil (21) of the electronic pen (2) by electromagnetic induction, and a signal is transmitted.

[0100] Conversely, when a control signal to turn off is supplied to the switch circuit (SW2), a control signal to turn on is supplied to the sample hold circuit (170). In this case, the switch circuit (SW2) is switched to the terminal (Ra) side and grounded, and the sample hold circuit (170) is operated. Because of this, current flows through the planar coil (160) by electromagnetic induction under the influence of the magnetic flux generated by the coil (21) of the electronic pen (2), and an induced voltage is generated, which is sampled and maintained by the sample hold circuit (170).

[0101] In this way, by repeatedly transmitting and receiving a signal through electromagnetic induction via a planar coil (160), if an induction voltage greater than a predetermined value is detected, it can be detected that an electronic pen (2) is stored in the storage unit (11). Conversely, if an induction voltage greater than a predetermined value is not detected, it can be detected that an electronic pen (2) is not stored in the storage unit (11).

[0102] Then, the processing control unit (150) determines whether the electronic pen (2) is stored in the storage unit (11) based on the result of the storage detection processing of step S101 (step S102). In step S102, it is determined that the electronic pen (2) is not stored in the storage unit (11). In this case, since the electronic pen (2) is in a state of use, the processing control unit (150) activates the position detection sensor (110), which is the main sensor, and initiates the detection processing of the indication position and pen pressure by the electronic pen (2) through the position detection sensor (110) (step S103).

[0103] Specifically, in step S103, the processing control unit (150) controls the selection circuit (113), the switch circuit (SW1), the sample hold circuit (133) of the position detection circuit unit (130), and the sample hold circuit (143) of the pressure detection circuit unit (140) by supplying a control signal. In this case, the processing is initiated to alternately switch between a transmission period in which current from the oscillation circuit unit (120) is supplied to the selected loop coil and a reception period in which a signal from the electronic pen (2) is received through the selected loop coil, along with sequentially selecting the loop coil used for transmitting and receiving signals from the loop coil group (111, 112). And, during the reception period, through the position detection circuit (130) and the pressure detection circuit (140), the detection of the indicated position by the electronic pen (2) on the position detection sensor (110) and the detection of the pressure applied to the electronic pen (2) by the electronic pen (2) coming into contact with the position detection sensor (110) are performed.

[0104] Afterwards, the processing control unit (150) performs a storage detection process to detect whether the electronic pen (2) is stored in the storage unit (11) using a sub-sensor, a planar shape coil (160), at an appropriate timing, as in the processing performed in step S101 (step S104). Then, the processing control unit (150) determines whether the electronic pen (2) is stored in the storage unit (11) based on the result of the storage detection process of step S104, as in the determination process performed in step S102 (step S105).

[0105] In the determination process of step S105, when it is determined that the electronic pen (2) is not stored in the storage unit (11), the processing control unit (150) repeats the process from step S104. By doing so, until the electronic pen (2) is stored in the storage unit (11), the detection of the indication position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) are continuously performed through the position detection sensor (110), which is the main sensor.

[0106] Meanwhile, in the determination process of step S105, it is determined that the electronic pen (2) is stored in the storage unit (11). In this case, since the electronic pen (2) is not in use, the processing control unit (150) terminates the detection process of the indication position and pen pressure through the main sensor, the position detection sensor (110) (step S106).

[0107] Specifically, in step S106, the processing control unit (150) stops supplying control signals to the selection circuit (113), the switch circuit (SW1), the sample hold circuit (133) of the position detection circuit unit (130), and the sample hold circuit (143) of the pressure detection circuit unit (140). By doing so, the operation of each unit is stopped, thereby terminating the processing of detecting the indicated position by the electronic pen (2) through the position detection sensor (110) and detecting the pressure applied to the electronic pen (2).

[0108] Afterward, the processing control unit (150) determines whether the main power of the electronic device body (1) is turned off (step S107). In the determination process of step S107, if it is determined that the main power is not turned off, the processing from step S101 is repeated. Also, in the determination process of step S107, if it is determined that the main power is turned off, a predetermined termination process, such as stopping the supply of power to the processing control unit (150), is performed (step S108), and the processing shown in FIG. 6 is terminated.

[0109] In addition, in the determination process of the above-described step S102, it is determined that the electronic pen (2) is stored in the storage unit (11). Even in this case, since the electronic pen (2) is not in use, the processing control unit (150) does not detect the indicated position and pen pressure through the main sensor, the position detection sensor (110), and determines whether the main power of the electronic device body (1) is turned off (step S107).

[0110] In the determination process of step S107, if it is determined that the main power is not off, the process from step S101 is repeated. Also, in the determination process of step S107, if it is determined that the main power is off, a predetermined termination process, such as stopping the supply of power to the processing control unit (150) (step S108), is performed to terminate the process shown in FIG. 6.

[0111] In this way, the processing control unit (150) can appropriately detect whether the electronic pen (2) is stored in the storage unit (11) by using a planar shape coil (160), which is a sub-sensor. Then, only when the electronic pen (2) is not stored in the storage unit (11) and is in a state of use, can the detection of the indication position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) be performed through the position detection sensor (110), which is a main sensor. By doing so, when the electronic pen (2) is stored in the storage unit (11), the detection of the indication position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) through the position detection sensor (110) are not performed, thus contributing to saving power consumption.

[0112] In addition, since a flat-shaped coil (160) is used as a sub-sensor, for example, by using resist technology to cover the flat-shaped coil (160) with a waterproof sheet such as resin, the gap can be completely sealed, making it easy to achieve a waterproof specification. Also, since a flat-shaped coil (160) is used, the complexity of the manufacturing process can be avoided compared to the case where a coil formed in a spiral shape is used, and it can also contribute to thinning.

[0113] [Second Embodiment]

[0114] FIG. 7 is a block diagram for explaining the schematic configuration of an electronic pen of an embodiment and a position detection device (100A) of a second embodiment. The position detection device (100A) of the second embodiment described below is also of the electromagnetic induction type, like the position detection device (100) of the first embodiment, and is mounted and used together with an electrostatic coupling type position detection device within the electronic device body (1) shown in FIG. 1. Accordingly, this position detection device (100A) of the second embodiment is also operated by the electronic pen (2) described using FIG. 1 and FIG. 2.

[0115] For this reason, the position detection device (100A) of this second embodiment also has a function to detect whether an electronic pen (2) is stored in the storage unit (11). However, the position detection device (100A) of this second embodiment does not have a insertion sensor circuit unit consisting of a flat shape coil (160), a switch circuit (SW2), a sample hold circuit (170), and an inversion circuit (IV), as shown in FIG. 7, which was provided by the position detection device (100) of the first embodiment.

[0116] The position detection device (100A) of this second embodiment is composed of a planar coil (160A) as a sub-sensor and a position detection circuit (main sensor) and has a configuration in which the position detection circuit also functions as an insertion / removal sensor circuit. The basic configuration of the position detection circuit is the same as that of the position detection device (100) of the first embodiment described above. For this reason, in FIG. 7, which is a block diagram of the position detection device (100A) of this second embodiment, the same reference numerals are assigned to parts configured as in the position detection device (100) of the first embodiment shown in FIG. 3, and the detailed description of those parts is omitted as it is redundant.

[0117] And, the planar coil (160A) of this second embodiment is also provided near the storage portion (11) of the electronic pen (2) provided in the electronic device body (1), just as in the case of the planar coil (160) of the first embodiment. In the position detection device (100A) of this second embodiment, the magnetic flux generated by the planar coil (160A) in a different direction does not act uniformly on the coil (21) of the electronic pen (2) stored in the storage portion (11). That is, in the position detection device (100A) of this second embodiment, the positional relationship between the coil (21) of the electronic pen (2) stored in the storage portion (11) and the planar coil (160A) placed near the storage portion (11) is such that it is the relationship described using FIG. 4(B) and FIG. 5.

[0118] As shown in FIG. 7, in the case of the position detection device (100A) of this second embodiment, one end of the planar coil (160A) which serves as a sub-sensor is connected to the selection circuit (113A), and the other end is grounded. The rest of the configuration is the same as that of the position detection device (100) of the first embodiment shown in FIG. 3.

[0119] Accordingly, in the position detection device (100A) of this second embodiment, when detecting whether an electronic pen (2) is stored in the storage unit (11), the processing control unit (150) controls the selection circuit (113A) to select the flat shape coil (160A). Then, the processing control unit (150) controls the switch circuit (SW1) to switch between a period (transmission period) during which current from the oscillation circuit unit (120) is supplied to the flat shape coil (160A) and a period (reception period) during which voltage generated at both ends of the flat shape coil (160A) by electromagnetic induction is detected. During this reception period, the processing control unit (150) activates the position detection circuit unit (130) to detect whether the flat shape coil (160A) is receiving a signal from the coil (21) of the electronic pen (2) by electromagnetic induction, thereby detecting whether the electronic pen (2) is stored in the storage unit (11).

[0120] Meanwhile, the detection of the indication position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) are performed in exactly the same way as in the case of the position detection device (100) of the first embodiment described above. That is, the processing control unit (150) controls by supplying control signals to the selection circuit (113A), the switch circuit (SW1), the sample hold circuit (133) of the position detection circuit unit (130), and the sample hold circuit (143) of the pen pressure detection circuit unit (140).

[0121] In this case, a process is performed to alternately switch between a transmission period in which current from the oscillation circuit (120) is supplied to the selected loop coil and a reception period in which a signal from the electronic pen (2) is received through the selected loop coil, along with sequentially selecting a loop coil used for transmitting and receiving signals from the loop coil group (111, 112). Then, during the reception period, through the position detection circuit (130) and the pressure detection circuit (140), the position of the electronic pen (2) on the position detection sensor (110) is detected, and the pressure applied to the electronic pen (2) is detected by the electronic pen (2) coming into contact with the position detection sensor (110).

[0122] In this way, in the case of the position detection device (100A) of this second embodiment, detection of whether an electronic pen (2) is stored in the storage portion (11) can be performed using a planar coil (160A) as a sub-sensor. In addition, in the case of the position detection device (100A) of this second embodiment, detection of the indicated position on the position detection sensor (110) by the electronic pen (2) and detection of the pen pressure applied to the electronic pen (2) can be performed.

[0123] [Specific example of control in the position detection device (100A)]

[0124] Next, a specific example of processing control by the processing control unit (150) of the position detection device (100A) of the second embodiment having the configuration described using FIG. 7 will be described. FIG. 8 is a flowchart for explaining processing executed by the processing control unit (150) of the position detection device (100A) of the second embodiment after the main power of the electronic device body (1) is turned on. The processing of the flowchart shown in FIG. 8 is to which the "method for controlling a position detection sensor" of the invention related to the present application is applied.

[0125] The processing control unit (150) first performs a storage detection process to detect whether the electronic pen (2) is stored in the storage unit (11) using a sub-sensor, a flat shape coil (160A) (step S201). Specifically, the processing control unit (150) controls the selection circuit (113A) to select the flat shape coil (160A) and maintains it. Then, it forms a control signal that alternately repeats an on period and an off period, and supplies this to the switch circuit (SW1). In addition, during the off period, it controls the sample hold circuit (133) of the position detection circuit unit (130) to operate.

[0126] In this way, the transmission and reception of a signal by electromagnetic induction through a planar coil (160A) are repeated, and if an induction voltage greater than a predetermined value is detected through the position detection circuit (130) during the reception period, it can be detected that an electronic pen (2) is stored in the storage unit (11). Conversely, if an induction voltage greater than a predetermined value is not detected through the position detection circuit (130) during the reception period, it can be detected that an electronic pen (2) is not stored in the storage unit (11).

[0127] Then, the processing control unit (150) determines whether the electronic pen (2) is stored in the storage unit (11) based on the result of the storage detection processing of step S201 (step S202). In step S202, it is determined that the electronic pen (2) is not stored in the storage unit (11). In this case, since the electronic pen (2) is in use, the processing control unit (150) activates the position detection sensor (110), which is the main sensor, and initiates the detection processing of the indication position and pen pressure by the electronic pen (2) through the position detection sensor (110) (step S203). The processing of step S203 is the same as the processing of step S103 performed in the position detection device (100) of the first embodiment shown in FIG. 6.

[0128] Afterward, the processing control unit (150) switches the selection circuit (113A) to select the planar shape coil (160A) at a predetermined timing and executes a storage detection process to detect whether the electronic pen (2) is stored in the storage unit (11) (step S204). That is, the processing of step S204 is the same as the processing executed in step S201. In addition, the predetermined timing is a timing such as when a predetermined detection process of one cycle is completed and the detection process of the next cycle is started in the detection process of the indication position and pen pressure initiated in step S203.

[0129] Additionally, a predetermined detection process of one cycle refers to a set of detection processes, such as starting the detection process until the indication position and pen pressure can be detected, or until the scanning process using all loop coils of the position detection sensor (110) is completed. Therefore, when the detection process of that one cycle is completed, a new detection process is started. Because of this, the detection process of the electronic pen (2) can be performed between the detection process of the previous one cycle and the detection process of the next one cycle, thereby allowing the detection process of the electronic pen (2) to be performed without affecting the detection process of the indication position and pen pressure of the electronic pen (2).

[0130] Then, the processing control unit (150) determines whether the electronic pen (2) is stored in the storage unit (11) based on the result of the storage detection process of step S204, as in the determination process performed in step S202 (step S205).

[0131] In the determination process of step S205, when it is determined that the electronic pen (2) is not stored in the storage unit (11), the processing control unit (150) repeats the process from step S204. By doing so, until the electronic pen (2) is stored in the storage unit (11), the detection of the indication position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) through the position detection sensor (110), which is the main sensor, are continuously performed.

[0132] Meanwhile, in the determination process of step S205, it is determined that the electronic pen (2) is stored in the storage unit (11). In this case, since the electronic pen (2) is not in use, the processing control unit (150) terminates the detection process of the indication position and pen pressure through the main sensor, the position detection sensor (110) (step S206).

[0133] Specifically, in step S206, the processing control unit (150) controls the selection circuit (113A) to maintain the selected state of the planar shape coil (160A) and to repeat the transmission and reception of signals through the planar shape coil (160A). Accordingly, in step S206, the loop coil constituting the X-axis direction loop coil group (111) and the loop coil constituting the Y-axis direction loop coil group (112) are not selected. As a result, since the detection processing of the indicated position by the electronic pen (2) using the position detection sensor (110), which is the main sensor, is not performed, power consumption can be significantly reduced.

[0134] In addition, in this case, since the oscillation circuit unit (120), the position detection circuit unit (130), and the processing control unit (150) are maintained in an operating state, it is possible to detect when the electronic pen (2) is taken out of the storage unit (11). Also, when the electronic pen (2) is stored in the storage unit (11), there is no need to operate the pressure detection circuit unit (140), so the operation of the pressure detection circuit unit (140) may be stopped.

[0135] Afterward, the processing control unit (150) determines whether the main power of the electronic device body (1) is turned off (step S207). In the determination process of step S207, if it is determined that the main power is not turned off, the processing from step S201 is repeated. Also, in the determination process of step S207, if it is determined that the main power is turned off, a predetermined termination process, such as stopping the supply of power to the processing control unit (150), is performed (step S208), and the processing shown in FIG. 8 is terminated.

[0136] In addition, in the determination process of the above-described step S202, it is determined that the electronic pen (2) is stored in the storage unit (11). Even in this case, since the electronic pen (2) is not in use, the processing control unit (150) does not detect the indicated position and pen pressure through the position detection sensor (110), which is the main sensor, and determines whether the main power of the electronic device body (1) is turned off (step S207).

[0137] In the determination process of step S207, if it is determined that the main power is not off, the process from step S201 is repeated. Also, in the determination process of step S207, if it is determined that the main power is off, a predetermined termination process, such as stopping the supply of power to the processing control unit (150) (step S208), is performed to terminate the process shown in FIG. 8.

[0138] In this way, even in the case of the position detection device (100A) of this second embodiment, the processing control unit (150) can appropriately detect whether the electronic pen (2) is stored in the storage unit (11) by using a planar shape coil (160A), which is a sub-sensor. Then, only when the electronic pen (2) is not stored in the storage unit (11) and is in a state of use, can the detection of the indicated position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) be performed through the position detection sensor (110), which is a main sensor. By doing so, when the electronic pen (2) is stored in the storage unit (11), the detection of the indicated position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) through the position detection sensor (110) are not performed, thus contributing to saving power consumption.

[0139] In addition, since a flat coil (160A) is used as a sub-sensor, gaps can be completely sealed by using, for example, a waterproof sheet, making it easy to achieve a waterproof specification. Furthermore, since a flat coil (160A) is used, complexity in the manufacturing process can be avoided compared to using a coil formed in a spiral shape, and it can also contribute to thinning.

[0140] [Third Embodiment]

[0141] FIG. 9 is a block diagram for explaining a position detection device (100B) of a third embodiment. The position detection device (100B) of the third embodiment described below is also of the electromagnetic induction type, like the position detection devices (100, 100A) of the first and second embodiments, and is mounted and used together with an electrostatic coupling type position detection device within the electronic device body (1) shown in FIG. 1. Accordingly, this position detection device (100B) of the third embodiment is also operated by the electronic pen (2) described using FIG. 1 and FIG. 2.

[0142] For this reason, the position detection device (100B) of this third embodiment also has a function to detect whether an electronic pen (2) is stored in the storage portion (11). However, the position detection device (100B) of this third embodiment does not have a dedicated planar coil (160, 160A) as a sub-sensor, as in the position detection devices (100, 100A) of the first and second embodiments described above.

[0143] The position detection device (100B) of this third embodiment is configured such that one of the loop coils among the loop coil groups (111, 112) constituting the position detection sensor (110), as shown in FIG. 9, is also used as a planar coil as a sub-sensor. In the example shown in FIG. 9, the Xa-th loop coil of the X-axis direction loop coil group (111) is shown as being used as a planar coil as a sub-sensor. That is, in the case of the position detection device (100B) of this third embodiment, the Xa-th loop coil of the X-axis direction loop coil group (111) is extended to form a planar coil portion that functions as a sub-sensor near the storage portion (11).

[0144] Accordingly, in the case of the position detection device (100B) of this third embodiment, the position detection circuit section (130) has a configuration in which it also functions as an insertion sensor circuit section. Furthermore, the part of the position detection device (100B) other than the Xa-th loop coil of the X-axis direction loop coil group (111) is configured as in the position detection device (100) of the first embodiment described above. For this reason, in FIG. 9, which is a block diagram of the position detection device (100B) of this third embodiment, the same reference numeral is assigned to the part configured as in the position detection device (100) of the first embodiment shown in FIG. 3, and the detailed description of that part is omitted as it is redundant.

[0145] In addition, in this third embodiment, the positional relationship between the Xa-th loop coil, which is extended to function as a sub-sensor near the storage unit (11), and the coil (21) of the electronic pen (2) stored in the storage unit (11) is the same as in the first embodiment. That is, in the position detection device (100B) of this third embodiment, the positional relationship between the coil (21) of the electronic pen (2) stored in the storage unit (11) and the planar coil portion formed by extending the Xa-th loop coil placed near the storage unit (11) is such that it is the relationship described using FIG. 4(B) and FIG. 5. As a result, magnetic fluxes (Mfa, Mfb) of different directions generated by the corresponding planar coil portion do not act uniformly on the coil (21) of the electronic pen (2) stored in the storage unit (11).

[0146] And, in the case of the position detection device (100B) of this third embodiment, the processing control unit (150) performs processing control similar to the processing control performed by the processing control unit (150) of the position detection device (100A) of the second embodiment described using FIG. 8. However, the processing performed in each of steps S201, S204, and S206 shown in FIG. 8 is slightly different from that performed in the position detection device (100A) of the second embodiment.

[0147] That is, in the position detection device (100B) of this third embodiment, the processing control unit (150) performs the following processing in steps S201 and S204 shown in FIG. 8. First, the processing control unit (150) controls the selection circuit (113) to select the Xa-th loop coil, which forms a planar coil section near the storage section (11), and maintains it. Then, it forms a control signal that alternately repeats an on period and an off period, and supplies this to the switch circuit (SW1). In addition, during the off period, it controls the sample hold circuit (133) of the position detection circuit section (130) to operate.

[0148] In this way, the transmission and reception of a signal by electromagnetic induction through the Xa-th loop coil, which forms a planar coil portion near the storage portion (11), are repeated. If, during the reception period, an induction voltage greater than a predetermined value is detected through the position detection circuit (130), it can be detected that an electronic pen (2) is stored in the storage portion (11). Conversely, if an induction voltage greater than a predetermined value is not detected through the position detection circuit (130) during the reception period, it can be detected that an electronic pen (2) is not stored in the storage portion (11).

[0149] In addition, in the position detection device (100B) of this third embodiment, the processing control unit (150) performs the following processing in step S206 shown in FIG. 8. In step S206, the processing control unit (150) controls the selection circuit (113) to maintain the state of selecting the Xa-th loop coil forming the planar shape coil section, and to repeat the transmission and reception of signals through the Xa-th loop coil. Accordingly, in step S206, excluding the Xa-th loop coil, the loop coil constituting the X-axis direction loop coil group (111) and the loop coil constituting the Y-axis direction loop coil group (112) are not selected. As a result, since the detection processing of the indicated position by the electronic pen (2) using the position detection sensor (110), which is the main sensor, is not performed, the power consumption can be significantly reduced.

[0150] In addition, in this case, since the oscillation circuit unit (120), the position detection circuit unit (130), and the processing control unit (150) are maintained in an operating state, it is possible to detect when the electronic pen (2) is taken out of the storage unit (11). Also, when the electronic pen (2) is stored in the storage unit (11), there is no need to operate the pressure detection circuit unit (140), so the operation of the pressure detection circuit unit (140) may be stopped.

[0151] The processing of the other steps S202, S203, S205, S207, and S208 is performed in the same manner as the processing performed by the position detection device (100A) of the second embodiment.

[0152] In this way, in the case of the position detection device (100B) of this third embodiment, one loop coil of the loop coil group constituting the position detection sensor (110) is extended and a flat coil portion is provided near the storage portion (11) to form a sensor circuit portion that detects whether an electronic pen (2) is stored in the storage portion (11).

[0153] In addition, in the case of the position detection device (100B) of this third embodiment, the processing control unit (150) can appropriately detect whether the electronic pen (2) is stored in the storage unit (11) by using the Xa-th loop coil of the position detection sensor (110). Then, only when the electronic pen (2) is not stored in the storage unit (11) and is in a state of use, can the detection of the indicated position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) be performed through the position detection sensor (110), which is the main sensor. By doing so, when the electronic pen (2) is stored in the storage unit (11), the detection of the indicated position by the electronic pen (2) and the detection of the pen pressure applied to the electronic pen (2) through the position detection sensor (110) are not performed, thus contributing to saving power consumption.

[0154] In addition, since a planar coil portion formed by extending the Xa-th loop coil of the position detection sensor (110) as a sub-sensor is used, the gap can be completely sealed by, for example, using a waterproof sheet, and thus it can be easily made waterproof. In addition, since a planar coil portion formed by extending the Xa-th loop coil of the position detection sensor (110) is used, the complexity of the manufacturing process can be avoided compared to the case where a coil is formed in a spiral shape, and it can also contribute to thinning.

[0155] [Effect of the implementation form]

[0156] In the position detection devices (100, 100A, 100B) of the first, second, and third embodiments described above, it is possible to achieve waterproof specifications, avoid complexity in the manufacturing process, and respond to the thinning of portable information terminals, while also achieving power saving. By doing so, it is possible to realize a position detection device suitable for use in portable information terminals and a control method for a position detection sensor.

[0157] In addition, in the case of the position detection device (100) of the first embodiment, unlike the position detection circuit, a sensor circuit that detects whether an electronic pen (2) is stored in the storage unit (11) can be configured, so that a position detection device that is easy to control can be realized.

[0158] In addition, in the case of the position detection device (100A) of the second embodiment, by simply providing a flat-shaped coil (160A) as a sub-sensor that detects whether an electronic pen (2) is stored in the storage portion (11), both the position detection circuit portion and the insertion / discharge sensor circuit portion can be configured, thereby enabling the configuration of a position detection device (100A) with a simple configuration.

[0159] In addition, in the case of the position detection device (100B) of the third embodiment, one of the loop coils of the loop coil group constituting the position detection sensor (110) is used as a sub-sensor to detect whether the electronic pen (2) is stored in the storage portion (11). By doing so, a position detection device (100B) with a simpler configuration can be constructed.

[0160] [Variation Example]

[0161] In the above-described embodiment, it was explained that both an electromagnetic induction type position detection device and an electrostatic coupling type position detection device are mounted on the electronic device body (1), but this is not limited thereto. It goes without saying that the present invention can be applied even when only an electromagnetic induction type position detection device is mounted.

[0162] In addition, the number of turns and shape of the planar coil portion formed using the planar coil (160, 160A) as a sub-sensor or the loop coil constituting the position detection sensor can be appropriate. For example, in the above-described embodiment, the planar coil portion formed using the planar coil (160, 160A) or the loop coil constituting the position detection sensor was shown as being formed in a spherical shape, but it may be formed in an elliptical shape or a circular shape.

[0163] In addition, it is possible to form a planar coil portion using a planar coil (160, 160A) or a loop coil constituting a position detection sensor, such as widening the width of the portion close to the coil embedded in the electronic pen and narrowing the width of the portion away. That is, the shape of the planar coil portion formed using a planar coil (160, 160A) or a loop coil constituting a position detection sensor can be made in various shapes.

[0164] In addition, the planar coil (160, 160A) and the loop coil (Xa) can be placed in a position where the number of magnetic fluxes that link the coil (21) in opposite directions among the magnetic fluxes generated for the coil (21) of the electronic pen (2) stored in the storage unit (11) is not equal.

[0165] More preferably, the planar coil (160, 160A) and the loop coil (Xa) may be positioned such that only magnetic flux with the same direction as the coil (21) of the electronic pen (2) stored in the storage unit (11) intersects. In this case, as shown in FIG. 4(B), the coil (21) of the electronic pen (2) stored in the storage unit (11) may be positioned in the direction of the central axis of the planar coil (160, 160A) and the loop coil (Xa) so as to overlap a part of the planar coil (160, 160A) and the loop coil (Xa).

[0166] Of course, as shown in FIG. 4(B), it is not a mandatory configuration for the coil (21) of the electronic pen (2) to span a portion of the planar coil (160, 160A) and the loop coil (Xa). It is sufficient to position the magnetic flux generated by the planar coil (160, 160A) and the loop coil (Xa) such that only the magnetic flux with the same direction intersects the coil (21) of the electronic pen. Explanation of the symbols

[0167] 1… Electronic device main body, 100, 100A, 100B… Position detection device, 110… Position detection sensor, 111… X-axis loop coil group, 112… Y-axis loop coil group, 113… Selection circuit, SW1, SW2… Switch circuit, AP… Amplifier, 120… Oscillation circuit section, 130… Position detection circuit section, 140… Pressure sensitivity detection circuit section, 150… Processing control section, 160, 160A… Planar shape coil, 170… Sample hold circuit, IV… Inversion circuit, 2… Electronic pen, 21… Coil, 22… Ferrite core, 23… Housing, 24… Core

Claims

Claim 1 A position detection device comprising: a main body having a housing that surrounds an electronic pen while the electronic pen is stored in a storage portion included in a housing; and a planar coil having a spherical cross-sectional area, wherein the planar coil is positioned in close proximity to the storage portion at a position where a direction perpendicular to the spherical cross-sectional area of ​​the planar coil intersects the axis direction of the electronic pen while the electronic pen is stored in the storage portion. Claim 2 A position detection device according to claim 1, wherein the electronic pen has a position indicating coil wound in the axial direction of the electronic pen, the planar coil extends substantially parallel to the axial direction of the electronic pen while the electronic pen is stored in the storage portion, and, during operation, the number of first magnetic fluxes linked in a first direction with respect to the position indicating coil of the electronic pen among the magnetic fluxes generated by the planar coil is not equal to the number of second magnetic fluxes linked in a second direction with respect to the position indicating coil of the electronic pen among the magnetic fluxes generated by the planar coil, and the first direction is opposite to the second direction. Claim 3 A position detection device according to claim 2, wherein the planar coil is positioned such that, while the electronic pen is stored in the storage portion, only magnetic flux having the same direction among the generated magnetic fluxes links with the position indicator coil of the electronic pen. Claim 4 A position detection device according to claim 2, wherein the planar shape coil is positioned such that, while the electronic pen is stored in the storage portion, the central axis direction of the planar shape coil passes through at least a part of the position indicator coil of the electronic pen, or at another position where the position indicator coil of the electronic pen is shifted relative to at least a part of the planar shape coil. Claim 5 A position detection device according to claim 1, further comprising: a first control circuit that performs control such that, during operation, a supply process in which a first signal is supplied to the planar shape coil and a reception process in which a second signal is received through the planar shape coil by electromagnetic induction are alternately executed; and a first detection circuit that, during operation, detects the storage state of the electronic pen in the storage portion according to the presence or absence of the second signal received through the planar shape coil. Claim 6 In claim 5, a position detection sensor configured to detect a position indicated by the electronic pen in an operation area, comprising a plurality of first loop coils arranged in a first direction and a plurality of second loop coils arranged in a second direction intersecting the first direction, wherein the planar coil is arranged outside the operation area where the position indicated by the electronic pen can be detected by the position detection sensor; a second control circuit that, during operation, specifies a first loop coil among the plurality of first loop coils and the plurality of second loop coils to transmit a third signal, supplies the third signal to the specified first loop coil, specifies a second loop coil among the plurality of first loop coils and the plurality of second loop coils to receive a fourth signal, and performs control to receive the fourth signal through the specified second loop coil; and a position detection control circuit that, during operation, controls the operation of at least the second control circuit to stop while the first detection circuit detects that the electronic pen is stored in the storage portion. A position detection device further comprising a second detection circuit that detects a position indicated by the electronic pen on the position detection sensor based on a fourth signal from the specified second loop coil during operation. Claim 7 A position detection device according to claim 6, wherein the first control circuit and the second control circuit are composed of a single control circuit; and the first detection circuit and the second detection circuit are composed of a single detection circuit. Claim 8 A position detection device according to claim 6, wherein the planar shape coil is formed using one of the plurality of first loop coils and the plurality of second loop coils of the position detection sensor; the first control circuit and the second control circuit are composed of a single control circuit; and the first detection circuit and the second detection circuit are composed of a single detection circuit. Claim 9 In claim 6, the first and second loop coils are position detection devices different from the planar shape coil. Claim 10 A position detection device according to claim 1, wherein a magnetic sheet or an electromagnetic shield is disposed on one side of the planar coil. Claim 11 A control method for a position detection sensor used in a position detection device, comprising: providing a main body having a housing that surrounds an electronic pen while the electronic pen is stored in a storage portion included in a housing; and providing a planar coil having a spherical cross-sectional area close to the storage portion while the electronic pen is stored in the storage portion, at a position where a direction perpendicular to the spherical cross-sectional area of ​​the planar coil intersects the axial direction of the electronic pen. Claim 12 A control method according to claim 11, wherein the electronic pen has a position indicating coil wound in the axial direction of the electronic pen, the planar coil extends substantially parallel to the axial direction of the electronic pen while the electronic pen is stored in the storage portion, and among the magnetic flux generated by the planar coil, the number of first magnetic flux links in a first direction with respect to the position indicating coil of the electronic pen is not equal to the number of second magnetic flux links in a second direction with respect to the position indicating coil of the electronic pen among the magnetic flux generated by the planar coil, and the first direction is opposite to the second direction. Claim 13 A control method according to claim 11, wherein providing the planar shape coil comprises providing the planar shape coil close to the storage portion at a position where the central axis direction of the planar shape coil intersects the axis direction of the electronic pen while the electronic pen is stored in the storage portion, and wherein the number of first magnetic flux links in a first direction with respect to the position indicator coil of the electronic pen among the magnetic flux generated by the planar shape coil is not equal to the number of second magnetic flux links in a second direction with respect to the position indicator coil of the electronic pen among the magnetic flux generated by the planar shape coil. Claim 14 A control method according to claim 11, wherein providing the planar shape coil comprises providing the planar shape coil at a position where, while the electronic pen is stored in the storage portion, only magnetic flux having the same direction among the generated magnetic fluxes links with the position indicator coil of the electronic pen. Claim 15 A control method according to claim 11, wherein providing the planar shape coil comprises providing the planar shape coil at a position where the central axis direction of the planar shape coil passes through at least a portion of the position indicator coil of the electronic pen while the electronic pen is stored in the storage portion, or at another position where the position indicator coil of the electronic pen is shifted with respect to at least a portion of the planar shape coil. Claim 16 A control method according to claim 11, wherein a magnetic sheet or an electromagnetic shield is disposed on one side of the planar coil. Claim 17 A control method according to claim 11, comprising performing a first control process including alternately supplying a first signal to the planar shape coil and receiving a second signal through the planar shape coil by electromagnetic induction; and further comprising detecting the storage state of the electronic pen in the storage portion according to the presence or absence of the second signal received through the planar shape coil extending substantially parallel to the axis of the electronic pen while the electronic pen is stored in the storage portion. Claim 18 A control method according to claim 17, wherein the position detection sensor comprises a plurality of first loop coils arranged in a first direction and a plurality of second loop coils arranged in a second direction intersecting the first direction, wherein a first loop coil to transmit a third signal among the plurality of first loop coils and the plurality of second loop coils is specified and the third signal is supplied to the specified first loop coil, wherein a second loop coil to receive a fourth signal among the plurality of first loop coils and the plurality of second loop coils is specified and the fourth signal is received through the specified second loop coil is performed; wherein a position indicated by the electronic pen on the position detection sensor is detected based on the fourth signal received through the specified second loop coil; and further comprising controlling not to perform the detection of the position indicated by the electronic pen through the second control processing and the position detection sensor while detecting that the electronic pen is stored in the storage portion. Claim 19 A control method according to claim 11, wherein the position detection sensor comprises a plurality of first loop coils arranged in a first direction and a plurality of second loop coils arranged in a second direction intersecting the first direction, and is configured to detect a position indicated by the electronic pen in an operation area, and the planar shape coil is arranged outside the operation area where the position indicated by the electronic pen can be detected by the position detection sensor. Claim 20 In claim 19, the control method wherein the first and second loop coils are different from the planar shape coil.

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