Electronic apparatus

Abstract

To provide an electronic apparatus that uses a position detection sensor to enable the installation of a part requiring access from the front side on the rear side.SOLUTION: An electronic apparatus comprises a position detection sensor disposed within a housing, a display screen provided on the operation input surface side of the position detection sensor, and a predetermined component disposed on the opposite side of the position detection sensor from the operation input surface. The position detection sensor includes an area on an insulating substrate where multiple position detection electrodes are disposed, which serves as an effective detection area for detecting the indicated position by a position indicator. The position detection sensors have through holes of a predetermined shape formed within the effective detection area, and the position detection electrodes are arranged so that the portions spanning the through holes follow the shape of the through holes and bypass them. The display screen displays an image indicating that the position corresponds to the operation position for the predetermined component at the position corresponding to the position of the predetermined component.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This invention relates to an electronic device using a position detection sensor.

Background Art

[0002] For example, in a portable electronic device, a position detection sensor is used as an operation input means, and is configured to be able to detect a position indicated by an indicator such as an electronic pen, with the surface panel of the housing as an input surface. In this type of portable electronic device, a display device composed of, for example, an LCD (Liquid Crystal Display) is disposed directly below the transparent surface panel, and, for example, a position detection sensor of an electromagnetic induction method is disposed on the back side of the display device so as to overlap the display screen of the display device. (See, for example, Patent Document 1).

[0003] Recently, by setting the area reaching up to the outer peripheral end of the housing of a portable electronic device as the display area of the display screen, it has become possible to realize a large display screen even with a small housing. And the position detection sensor has also come to be configured such that almost the entire display area of the display screen is an effective area for detecting an indicated position by an indicator. In this case, the entire area of the display screen corresponding to the effective area of the position detection sensor constitutes an operation input surface for an indicator such as an electronic pen.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the case of the portable electronic device as described above, the electronic circuit unit is usually disposed in the space further behind the position detection sensor.

[0006] In recent years, the functionality of portable electronic devices has advanced, and various components are being mounted on the electronic circuit board. Among these components, there are components that should be optically exposed without being shielded when viewed from the display screen side, such as display elements like LEDs (Light Emitting Diodes), and components that read information such as biometric information input from the display screen side, such as fingerprint sensors that read fingerprints of fingers, which are also being used.

[0007] Conventionally, such components were arranged in end regions such as the lower end or upper end of the surface panel of the housing of the electronic device, and display screens such as position detection sensors and LCDs were arranged so as not to block the upper part of those components. As a result, the size of the display screen became smaller, and the effective area of the position detection sensor also became smaller accordingly.

[0008] However, recently, even when provided on the back side of an LCD as an example of a display device, components that can function effectively for operations and access from the front side of the LCD without being obstructed by the LCD have emerged. For example, as a fingerprint sensor, an ultrasonic type is known. When this ultrasonic fingerprint sensor is used, even if it is provided on the back side of the LCD, it can detect the fingerprint of a finger placed on the surface panel without being affected by the LCD. Therefore, when using this ultrasonic fingerprint sensor, it is possible to arrange the fingerprint sensor in the area within the display screen of the display device, and image display on the LCD display screen is also possible as it is even in the area where the fingerprint sensor is arranged.

[0009] However, in the case of an electronic device that enables instruction input by an indicator such as an electronic pen by disposing a position detection sensor as described above on the back side of the LCD, a position detection sensor is disposed on the back side of the LCD, and further, an electronic circuit in which a fingerprint sensor or the like is disposed is disposed on the back side of the position detection sensor. In the case of an electronic device having such a configuration, due to the presence of the position detection sensor, there has been a risk that even an ultrasonic fingerprint sensor cannot detect the fingerprint of a finger placed on the surface panel.

[0010] Particularly, in the case of a position detection sensor using an electromagnetic induction method, in addition to the sensor substrate, a magnetic shielding material and an electromagnetic shielding material are provided, and because they interfere, there has been a risk that the functions of the components disposed in the electronic circuit provided on the back side of the position detection sensor with respect to the operation and access from the surface panel side may not work effectively.

[0011] In consideration of this point, conventionally, even for components that can be disposed on the back side within the display area of the LCD display screen, the position detection sensor has been disposed so as not to cover the upper part of the component. For this reason, the effective detection area of the position detection sensor has been made smaller than the LCD display area, or it has been necessary to configure the component to be disposed in an area that does not overlap with the LCD or the position detection sensor, as in the conventional case.

[0012] An object of the present invention is to provide an electronic device using a position detection sensor capable of solving the above problems.

Means for Solving the Problem

[0013] In order to solve the above problems, an electronic device in which a position detection sensor is disposed in a housing, a display screen is provided on the operation input surface side with respect to the position detection sensor, and a predetermined component is disposed on the back side of the position detection sensor on the side opposite to the operation input surface, the position detection sensor is A position detection sensor is provided on an insulating substrate with a plurality of loop coils configured therein, and an area where the plurality of position detection electrodes are disposed is an effective detection area for detecting an input instruction on the display screen for detecting the position of a position indicator. In the position detection sensor, a through hole having a predetermined shape corresponding to the predetermined component is formed at a position corresponding to the position of the predetermined component within the effective detection area. The position detection electrode is disposed so as to bypass the through hole along the shape of the through hole at a portion spanning the through hole. On the display screen, an image notifying that it is an operation position for the predetermined component is displayed at a position corresponding to the position of the predetermined component. An electronic device characterized by the above is provided.

[0014] In the position detection sensor of the electronic device having the above-described configuration, a through hole having a predetermined shape is formed within the effective detection area. And in the position detection sensor, since the position detection electrode is formed so as to bypass the through hole along the shape of the through hole, the effective detection area of the position detection sensor is configured to include also the portion of the through hole.

[0015] Therefore, when disposing a component that is obstructed by being shielded by the position detection sensor on the back side of the effective detection area of the position detection sensor, by arranging the component at a position corresponding to the position of the through hole, it can function without any trouble.

Brief Description of the Drawings

[0016]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

[0017] Hereinafter, embodiments of the position detection sensor and the electronic device according to the present invention will be described with reference to the drawings.

[0018] [First Embodiment] FIG. 1 shows an example of an electronic device including an embodiment of a position detection sensor. The electronic device 1 in this example is a high - performance mobile phone terminal including a display device, in this example, the display screen 11D of an LCD (Liquid Crystal Display) 11. Below (the back side) of the LCD 11, the position detection sensor 2 of this embodiment is provided, and further on the back side of the position detection sensor 2, an electronic circuit (not shown in FIG. 1) described later is provided. The electronic circuit includes a position detection circuit connected to the position detection sensor 2.

[0019] In the electronic device 1 of this example, an electronic pen 3 is attached as an example of an indicator for performing a position indication input to the position detection sensor 2. In this embodiment, by transmitting and receiving signals by electromagnetic induction coupling between the electronic pen 3 and the position detection sensor 2, the position detection circuit detects the position within the effective region of position detection of the position detection sensor 2 indicated by the electronic pen 3. In this example, the entire display area of the display screen 11D of the LCD 11 is configured to be the effective region of position detection of the position detection sensor 2. Therefore, the entire display area of the display screen 11D constitutes the input surface of the position detection sensor 2, and the user can perform a position indication operation using the electronic pen 3 with the entire display area of the display screen 11D as the input surface.

[0020] In the electronic device 1, when a position indication input operation is performed on the display screen 11D with the electronic pen 3, an interaction of signals by electromagnetic induction coupling is performed between the position detection sensor 2 provided on the back side of the display screen 11D and the electronic pen 3, the position indicated and input by the electronic pen 3 is detected in the position detection circuit, and the computer to which the position detection circuit of the electronic device 1 is connected performs display processing according to the operation position on the display screen 11D.

[0021] FIG. 2 is an exploded perspective view for explaining a configuration example of the electronic device 1 of this embodiment. As shown in FIG. 2, in the electronic device 1 of this embodiment, the motherboard 12 is housed in the lowermost layer within the housing 10, the position detection sensor 2 is disposed thereon, and further, the LCD 11 is disposed thereon with the display screen 11D facing upward.

[0022] In this embodiment, the motherboard 12, the position detection sensor 2, and the LCD 11 are sequentially housed in a rectangular recess 10a surrounded by the peripheral frame of the rectangular housing 10. Above the LCD 11, a surface panel 13 made of, for example, transparent resin or transparent glass is disposed, and the electronic device 1 is configured by fixing the periphery of the surface panel 13 to the housing 10. The surface of the region of the surface panel 13 corresponding to the display screen 11D of the LCD 11 serves as the operation input surface for the electronic pen 3.

[0023] As shown in FIGS. 1 and 2, in the electronic device 1 of this embodiment, the thickness of the peripheral frame of the rectangular recess 10a of the housing 10 is thin, and the display screen 11D of the LCD 11 is made to occupy substantially the entire area of the recess 10a. Therefore, the effective area for position detection of the position detection sensor 2 also corresponds to the display area of the LCD 11 and occupies substantially the entire area of the recess 10a.

[0024] Here, on the motherboard 12, a communication circuit, a display control circuit for the display device 11, a circuit that supplies a signal to the position detection sensor 2 and receives the signal received through the position detection sensor 2 to detect the position indicated by the electronic pen 3 is formed. Although not shown in FIG. 2, the display device 11 and the position detection sensor 2 are respectively connected to corresponding circuit portions of the motherboard 12.

[0025] And in this embodiment, the electronic device 1 is configured to have a function of permitting the start of use of the electronic device 1 by fingerprint authentication of the user. As a component for this fingerprint authentication, a fingerprint sensor 14 for detecting the fingerprint of the user is disposed on the motherboard 12, and the electronic circuit of the motherboard 12 is configured to include a fingerprint authentication circuit to which the fingerprint information read by the fingerprint sensor 14 is supplied.

[0026] The fingerprint sensor 14 is an example of a predetermined component that may be unable to execute functions corresponding to operations and access in the area of the operation input surface of the surface panel 13 when shielded by the position detection sensor 2. The fingerprint sensor 14 used in this embodiment can recognize the fingerprint of the user's finger using ultrasonic waves. As described above, even if the LCD 11 exists between the fingerprint sensor 14 and the surface panel 13, the fingerprint reading function is not impaired. However, as described above, when the position detection sensor 2 exists between the fingerprint sensor 14 and the surface panel, there is a possibility that the fingerprint reading function may be impaired.

[0027] In view of this, in this embodiment, a through hole 2H is formed at a position corresponding to above the fingerprint sensor 14 of the motherboard 12 on the position detection sensor 2 disposed by being overlapped on the motherboard 12. In this embodiment, as shown in FIGS. 1 and 2, the through hole 2H has a rectangular shape corresponding to the shape and size of the fingerprint sensor 14. Note that the shape and size of the through hole 2H may be any shape and size that do not interfere with a predetermined component disposed on the back side of the position detection sensor 2 such as the fingerprint sensor 14 from reliably performing its intended function, and the shape is not limited to a rectangular shape, and may be, for example, a circle, an ellipse, a polygon such as a hexagon, or the like.

[0028] In this way, the fingerprint sensor 14 is disposed on the back side thereof within the display area of the display screen 11D of the LCD 11 and within the effective area of the position detection sensor 2.

[0029] In the electronic device 1 of this embodiment, as described above, when fingerprint authentication is used to determine whether to permit the start of use of the electronic device 1, the user places a finger in advance within the display area of the display screen 11D of the front panel 13 and allows the fingerprint sensor 14 to read the fingerprint of the finger to register the fingerprint of the finger. In this case, as shown in FIG. 1, an image 14P for notifying the user that it is a position where the fingerprint is to be read is displayed at a position corresponding to the fingerprint sensor 14 on the display screen 11D. The fingerprint sensor 14 stores the fingerprint information of the registered finger as authentication reference information. Then, after registering the fingerprint information of the finger as authentication reference information, the electronic device 1 executes fingerprint authentication by a fingerprint authentication application.

[0030] As is well known, when a user attempting to start the electronic device 1 places a finger on an image 14P within the display area of the display screen 11D of the front panel 13, the fingerprint authentication application reads the fingerprint of the finger with the fingerprint sensor 14 and checks whether it matches the fingerprint of the registered and stored finger to confirm whether the authentication is successful. Then, when it is confirmed that the authentication is successful, the fingerprint authentication application operates to permit the start of the use of the electronic device 1. The fingerprint authentication process by this fingerprint authentication application is performed only when starting the use of the electronic device 1.

[0031] As described above, after the start of the use of the electronic device 1 is permitted, the user can cause the electronic device to perform various functional processes by making a position indication input with the electronic pen 3 through the display area of the display screen 11D corresponding to the effective area of the position detection sensor 2.

[0032] By the way, as will be described later, the position detection sensor 2 of this embodiment is configured by arranging a plurality of position detection electrodes, in this case loop coils, in each of the X-axis direction (for example, the horizontal direction of the display screen 11D of the electronic device 1) and the Y-axis direction (for example, the vertical direction of the display screen 11D of the electronic device 1) that are orthogonal to each other. The arrangement pitch of the plurality of loop coils in the X-axis direction and the Y-axis direction is generally made relatively short so that the position indicated by the electronic pen 3 can be detected precisely.

[0033] In the case of this embodiment, when a through hole 2H is formed in the effective area of the position detection sensor 2, no position detection electrode can be formed in the portion of the through hole 2H. When the size of the through hole 2H is smaller than the arrangement pitch of the loop coils, by providing the through hole 2H in the space between the position detection electrodes constituting the loop coils, it is possible to prevent any hindrance to position detection.

[0034] However, when the size of the through hole 2H is larger than the arrangement pitch of the loop coils, the position detection electrode will necessarily be bridged across the portion of the through hole 2H. In this case, when the position detection electrode is bridged across the portion of the through hole 2H, it means that when the position detection electrode is arranged in the same manner as in the region where the through hole 2H does not exist, a part of the conductor constituting the position detection electrode will straddle the through hole 2H.

[0035] That is, in this example, each of the position detection electrodes is constituted by an elongated rectangular loop coil as described later and has four straight sides. When one or both of the long sides remain straight, if they straddle the through hole 2H, then the loop coil, that is, the position detection electrode, will be bridged across the through hole 2H. Note that the shape of the loop coil is not limited to a rectangular shape, and any shape is acceptable as long as at least a part of the conductor constituting the loop coil straddles the through hole 2H when the position detection electrode is arranged in the same manner as in the region where the through hole 2H does not exist.

[0036] When a plurality of loop coils are arranged in the X-axis direction and the Y-axis direction to form the position detection sensor 2 and then the through hole 2H is formed later, the loop coil bridged across the portion of the through hole 2H will be divided by the through hole 2H, and the loop coil bridged across the through hole 2H cannot be used for detecting the position indicated by the electronic pen 3.

[0037] To avoid this problem, in this embodiment, the through hole 2H is formed in the insulating substrate in advance. For the insulating substrate, in the region where the through hole 2H does not exist, the loop coil is formed in the same manner as in the prior art. In the portion bridged across the through hole 2H, the loop coil is formed and arranged so as to bypass the through hole 2H along the shape of the through hole 2H without being divided by the through hole 2H.

[0038] [Configuration Example of Position Detection Sensor 2, Configuration Example of Position Detection Circuit, and Circuit Configuration Example of Electronic Pen] FIG. 3 is a diagram showing an outline of the arrangement of loop coils as position detection electrodes of the position detection sensor 2, a position detection circuit 100 connected to the position detection sensor 2, and the electronic circuit configuration of the electronic pen 3. As described above, the position detection sensor 2 of this embodiment performs signal interaction (interaction) with the resonance circuit RC of the electronic pen 3 by an electromagnetic induction method.

[0039] As shown in FIG. 3, the resonance circuit RC of the electronic pen 3 is configured by connecting in parallel a coil 31, a capacitor 32, and a variable capacitance capacitor 33 composed of a pen pressure detection unit, and this resonance circuit RC is electromagnetically inductively coupled to the position detection sensor 2.

[0040] As shown in FIG. 3, the position detection sensor 2 includes X-axis direction loop coils 21 arranged at a predetermined pitch in the X-axis direction (for example, the horizontal direction) and Y-axis direction loop coils 22 arranged at a predetermined pitch in the Y-axis direction (for example, the vertical direction). In this case, the plurality of X-axis direction loop coils 21 and Y-axis direction loop coils 22 are each arranged at a pitch narrower than the width of the loop so that the indicated position by the electronic pen 3 can be detected with high definition, and at the same time, so that the conductors constituting these loop coils 21, 22 do not overlap on the same surface, both the front and back surfaces of an insulating substrate (not shown in FIG. 3) are used and formed using through holes.

[0041] That is, when showing each one of the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 on the insulating substrate, it becomes as shown in FIG. 4. FIG. 4(A) shows one X-axis direction loop coil 21 and one Y-axis direction loop coil 22 arranged at a position not spanning the through hole 2H in the insulating substrate 20, and FIG. 4(B) shows one X-axis direction loop coil 21 and one Y-axis direction loop coil 22 arranged at a position spanning the through hole 2H in the insulating substrate 20. FIGS. 4(A) and (B) show the state seen from the surface side of the insulating substrate 20. The conductor of the loop coil arranged on the surface side of the insulating substrate 20 is shown by a solid line, and the conductor of the loop coil arranged on the back surface side of the insulating substrate 20 is shown by a broken line.

[0042] As shown in FIG. 4(A), in this example, the X-axis direction loop coil 21 has a vertically long rectangular loop shape, and the straight conductor on the long side thereof is formed on the surface of the insulating substrate 20, and the straight conductor on the short side is connected to the conductor on the long side through the through hole 23 and formed on the back surface. Further, the Y-axis direction loop coil 21 has a horizontally long rectangular loop shape, and the straight conductor on the long side thereof is formed on the back surface of the insulating substrate 20, and the straight conductor on the short side is connected to the conductor on the long side through the through hole 23 and formed on the surface.

[0043] And, as shown in FIG. 4(B), in the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 straddling the through hole 2H, in this example, the straight conductor on one side of the long side is deformed so as to bypass around the through hole 2H at the portion straddling the through hole 2H, and bypass portions 21a and 22a are formed.

[0044] Since the loop coil generates an electromotive force corresponding to the magnetic flux interlinking the area surrounded by the loop coil, when the loop shape of the loop coil is deformed, the area surrounded by the loop coil changes, and the electromotive force also changes. For this reason, a difference occurs in the reception signal level of the signal from the electronic pen 3 by electromagnetic induction coupling between the loop coil straddling the through hole 2H and the loop coil not straddling the through hole 2H.

[0045] In this embodiment, the bypass portions 21a and 22a of the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 are formed so as to draw the shortest path along the shape of the through hole 2H. In the example of FIG. 4(B), since the through hole 2H has a rectangular shape, the bypass portions 21a and 22a are formed as overhanging portions in which the straight conductor on the long side is bent at a right angle along the shape of the through hole 2H.

[0046] In this embodiment, as in this example, the detour portions 21a and 22a are formed so as to draw the shortest path along the shape of the through hole 2H. Thus, the deformation of the loop shapes of the X-axis direction loop coils 21 and the Y-axis direction loop coils 22 can be minimized. As a result, the difference in the reception signal level of the signal from the electronic pen 3 due to electromagnetic induction coupling can be minimized between the loop coils spanning the through hole 2H and the loop coils not spanning the through hole 2H.

[0047] FIG. 4(B) shows one state of the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H. However, when the formation pitch is smaller than the through hole 2H, a plurality of the X-axis direction loop coils 21 and the Y-axis direction loop coils 22 are in a state of spanning the through hole 2H. Also in this case, the plurality of X-axis direction loop coils 21 and Y-axis direction loop coils 22 spanning the through hole 2H are made such that the deformation of the loop shape caused by detouring the through hole 2H is minimized as much as possible.

[0048] FIG. 5 shows an example of the conductor arrangement pattern of a plurality of X-axis direction loop coils 21 and Y-axis direction loop coils 22 spanning the through hole 2H.

[0049] As shown in FIG. 5, in this example, on the insulating substrate 20 of the position detection sensor 2, the X-axis direction loop coils 21 are sequentially arranged in the X-axis direction at an arrangement pitch τx smaller than the X-axis direction opening width Lx of the rectangular through hole 2H, and the Y-axis direction loop coils 22 are sequentially arranged in the Y-axis direction at an arrangement pitch τy smaller than the Y-axis direction opening width Ly of the rectangular through hole 2H.

[0050] The example of FIG. 5 shows an example of the conductor detour pattern when one of the long sides of four X-axis direction loop coils 21 (shown as X-axis direction loop coils 211, 212, 213, 214 in FIG. 5) spans the through hole 2H and one of the long sides of two Y-axis direction loop coils 22 (shown as Y-axis direction loop coils 221, 222 in FIG. 5) spans the through hole 2H.

[0051] In the example of Fig. 5, on the linear conductors on one side of the long sides of the two leftmost X-axis direction loop coils 211 to 214 among the four X-axis direction loop coils 211 to 214, detour portions 211a and 212a that protrude to the left so as to bypass the left side of the through hole 2H are formed, and on the linear conductors on one side of the long sides of the two rightmost X-axis direction loop coils 213 and 214, detour portions 213a and 214a that protrude to the right so as to bypass the right side of the through hole 2H are formed.

[0052] In this case, the detour portions 211a and 212a, and also the detour portions 213a and 214a, are formed close to each other in order to minimize the deformation of the loop shapes of the respective X-axis direction loop coils 211 to 214, and are arranged without considering the arrangement pitch τx. However, it goes without saying that the detour portions 211a and 212a, and also the detour portions 213a and 214a, are insulated from each other.

[0053] Also, in the example of Fig. 5, on the linear conductor on one side of the long side of the upper Y-axis direction loop coil 221 among the two Y-axis direction loop coils 221 and 222, a detour portion 221a that protrudes upward so as to bypass the upper side of the through hole 2H is formed, and on the linear conductor on one side of the long side of the lower Y-axis direction loop coil 222, a detour portion 222a that protrudes downward so as to bypass the lower side of the through hole 2H is formed.

[0054] For the position detection sensor 2 configured as described above, a position detection circuit 100 is connected as shown in Fig. 3. In this position detection circuit 100, the position within the effective region of the position detection sensor 2 indicated by the electronic pen 3 is detected. In this example, the position detection circuit 100 transmits a signal to the resonance circuit RC of the electronic pen 3 by electromagnetic coupling through the position detection sensor 2, and the electronic pen 3 feeds back the signal received from the position detection sensor 2 to the position detection sensor 2 via the resonance circuit RC.

[0055] Then, in the position detection circuit 100, the feedback signal from the resonance circuit RC of the electronic pen 3 is received through the position detection sensor 2, and the position within the effective area of the position detection sensor 2 indicated by the electronic pen 3 is detected from the positions of the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 of the position detection sensor 2 where the received signal is detected. In this example, the change in the resonance frequency of the resonance circuit RC is detected by detecting the phase change of the signal received by electromagnetic coupling from the resonance circuit RC of the electronic pen 3, so as to detect the pen pressure applied to the electronic pen 3.

[0056] The position detection circuit 100 is provided with a selection circuit 101 to which the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 of the position detection sensor 2 are connected. Also, the position detection circuit 100 is provided with a processing control circuit 110 constituted by, for example, a computer.

[0057] The selection circuit 101 sequentially selects the X-axis direction loop coil 21 and the Y-axis direction loop coil 22, transmits a signal to the resonance circuit RC of the electronic pen 3, and receives the signal fed back from the resonance circuit RC.

[0058] A switching circuit 102 controlled by the processing control circuit 110 is connected to the selection circuit 101. When the switching circuit 102 is connected to the transmission side terminal T, an AC signal is supplied from the oscillator 103 to the selection circuit 101 through the amplifier 104, and when it is connected to the reception side terminal R, the reception signal from the selection circuit 101 is supplied to the indicated position detection circuit 106 and the pen pressure detection circuit 107 through the amplifier 105.

[0059] The circuit 106 for detecting the indicated position detects the induced voltages generated in the X-axis direction loop coil 21 and the Y-axis direction loop coil 22, that is, the received signals, converts the detected output signals into digital signals, and outputs them to the processing control circuit 110. The processing control circuit 110 calculates the coordinate values of the indicated positions in the X-axis direction and the Y-axis direction of the electronic pen 3 based on the digital signals from the circuit 106 for detecting the indicated position, that is, the levels of the voltage values of the induced voltages generated in the respective X-axis direction loop coil 21 and Y-axis direction loop coil 22.

[0060] In this case, in this embodiment, the processing control circuit 110 includes a correction circuit 111 corresponding to the fact that the position detection sensor 2 has the through hole 2H in the effective region.

[0061] This correction circuit 111 has a processing function (through hole inner indicated position calculation function) that enables the coordinate values of the indicated position to be calculated as accurately as possible when the indicated position by the electronic pen 3 is in the region within the through hole 2H, and even when the indicated position by the electronic pen 3 is in a region outside the through hole 2H, when it is necessary to detect the coordinate position from the received signal of the feedback signal from the resonance circuit of the electronic pen 3 in the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H, it has a function (through hole outer indicated position correction function) to correct so as to calculate the coordinate values of the indicated position more accurately.

[0062] The method of calculating the indicated position when the indicated position by the electronic pen 3 is in the region within the through hole 2H in the former through hole inner indicated position calculation function is, for example, as follows.

[0063] First, in advance, in the area within the through-hole 2H of the position detection sensor 2, a plurality of positions corresponding to the detection accuracy are indicated by the electronic pen 3. At each of the indicated positions, the output signal level of the indicated position detection circuit 106 for the signals obtained from one or more X-axis direction loop coils 21 and one or more Y-axis direction loop coils 22 spanning the through-hole 2H is acquired. Then, the information on the indicated position of the electronic pen 3 and the output signal level of the indicated position detection circuit 106 for the signals obtained from one or more X-axis direction loop coils 21 and one or more Y-axis direction loop coils 22 are associated with each other and stored in the first table memory 112 as the first table information. Note that the first table information may of course include the output signal levels of the X-axis direction loop coils 21 and Y-axis direction loop coils 22 not only spanning the through-hole 2H but also those in the vicinity thereof.

[0064] Then, when the processing control circuit 110 detects the position indicated by the electronic pen 3, when it determines that the indicated position is an area within the through-hole 2H, it compares the output signal level of the first table information in the first table memory 112 with the output signal level of the indicated position detection circuit 106 at that time, and acquires the matching or approximate indicated position from the first table information in the first table memory 112, so as to detect the indicated position in the area within the through-hole 2H. When a plurality of output signal levels of the first table information in the first table memory 112 are approximate to the output signal level of the indicated position detection circuit 106 at that time, an interpolation operation may be performed from the plurality of approximate output signal levels of the first table information to calculate a more accurate indicated position.

[0065] In this case, the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H are known in the position detection sensor 2. Therefore, to determine whether the position indicated by the electronic pen 3 is within the area of the through hole 2H, among the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 from which an output signal of a predetermined level or higher is obtained from the indicated position detection circuit 106, it can be determined by whether the X-axis direction loop coil and the Y-axis direction loop coil showing the peak value are the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H.

[0066] Next, the latter through-hole outer indicated position correction function will be described. As described above, since the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 have detour portions 21a and 22a in order to span the through hole 2H, the loop shape is deformed with respect to the other X-axis direction loop coil 21 and Y-axis direction loop coil 22 that do not span the through hole 2H.

[0067] Therefore, even when the indicated position by the electronic pen 3 is not in the area within the through hole 2H but in the area outside thereof, when the signal fed back from the resonance circuit RC of the electronic pen 3 is received by the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H, the output signal level may be different from that of the other X-axis direction loop coil 21 and Y-axis direction loop coil 22 that do not span the through hole 2H.

[0068] In this embodiment, the X-axis direction and Y-axis direction loop coils of the position detection sensor are in an elongated rectangular shape. Moreover, the electronic pen 3 is thin, and the magnetic flux due to the electromagnetic energy returned from the electronic pen 3 is concentrated around the position indicated by the electronic pen 3 and intersects with the loop coil. Therefore, when the size of the through hole 2H (the length in the X-axis direction and the length in the Y-axis direction) is smaller than the length in the long side direction of the loop coil, in the X-axis direction loop coil 21 and the Y-axis direction loop coil 22, the area where the magnetic flux due to the electromagnetic energy returned from the electronic pen 3 intersects changes when the position indicated by the electronic pen 3 is in a region within a predetermined range (excluding the inside of the through hole) around the through hole 2H. This predetermined range around the through hole 2H (hereinafter referred to as the correction required range) can be appropriately set by inspecting the output signals obtained from the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H by the magnetic flux due to the electromagnetic energy returned from the electronic pen 3 and determining the position range where correction is required or not.

[0069] Based on the above, in this embodiment, when the signal returned from the resonance circuit RC of the electronic pen 3 is received by the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H, the detection output level from the indication position detection circuit 106 is corrected when the position indicated by the electronic pen 3 is within the above correction required range, so that it can be handled in the same way as when there is no area change due to the detour portion of the through hole 2H. The processing control circuit 110 is provided with a second table memory 113 that stores second table information associated with each position within the above correction required range of each of the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through hole 2H for such correction signals.

[0070] When the position indicated by the electronic pen 3 is within the correction range, the processing control circuit 110 corrects the signal fed back from the resonance circuit RC of the electronic pen 3 according to the position indicated by the electronic pen 3 by using the correction signal of the second table information in the second table memory 113, based on the detection output level from the indication position detection circuit 106 when received by the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through-hole 2H, and uses it for the detection process of the coordinate position.

[0071] In the position detection sensor, for example, when a through-hole with a large longitudinal size of a rectangular loop coil is formed, regardless of the position indicated by the electronic pen 3 within the loop coil, the area of magnetic flux linkage due to the electromagnetic energy fed back from the electronic pen 3 is affected by the area change caused by including a detour portion that bypasses the through-hole.

[0072] In such a case, the detection output level from the indication position detection circuit 106 when received by the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 spanning the through-hole 2H is corrected regardless of the indication position by the electronic pen 3.

[0073] The pen pressure detection circuit 107 synchronously detects the output signal of the receiving amplifier 105 with the AC signal from the oscillator 103 to obtain a signal level corresponding to the phase difference (frequency deviation) between them, converts the signal corresponding to the phase difference (frequency deviation) into a digital signal, and outputs it to the processing control circuit 110. The processing control circuit 110 detects the pen pressure applied to the electronic pen 3 based on the digital signal from the pen pressure detection circuit 107, that is, the level of the signal corresponding to the phase difference (frequency deviation) between the transmitted radio wave and the received radio wave.

[0074] The processing control circuit 110 receives the pen pressure information detected by the pen pressure detection circuit 107, associates and holds it with the coordinate information of the indication position of the electronic pen 3 detected from the output signal of the indication position detection circuit 106, and outputs it to an external circuit as necessary.

[0075] As described above, the position detection sensor 2 of this embodiment is provided with a through hole 2H in the effective area corresponding to the fingerprint sensor 14 disposed on the back side of the effective area for position detection. Therefore, the fingerprint of the finger placed on the surface panel 13 can be read by the fingerprint sensor 14 disposed on the back side of the position detection sensor 2 without causing any trouble.

[0076] Then, in the position detection sensor 2, in the portion of the through hole 2H, the conductor of the loop coil spanning the through hole 2H is arranged to meander along the shape of the through hole 2H. Therefore, for the portion of the through hole 2H of the position detection sensor 2, there is no problem that the indicated position by the electronic pen 3 within the effective area cannot be detected.

[0077] In the position detection sensor 2 of this embodiment, the meandering portion of the loop coil spanning the through hole 2H is formed to meander through the through hole 2H along the shortest path. Therefore, the change in the area surrounded by the loop due to the change in the loop shape of the loop coil caused by the meandering portion can be minimized, and the change in the electromotive force due to the interlinked magnetic flux can be reduced. Further, when there are a plurality of loop coils spanning the through hole 2H, the meandering portions of these plurality of loop coils are arranged to be close to each other. Therefore, for each of these plurality of loop coils, the change in the loop area due to the deformation of the loop coil caused by the meandering portion can be reduced, and the change in the electromotive force due to the interlinked magnetic flux can be reduced.

[0078] In the position detection circuit of the above-described embodiment, the signal level of the received signal obtained from the loop coil spanning the through hole 2H is corrected by the correction signal composed of the second table information of the second table memory 133 in the correction range around the through hole 2H so as to be equal to the signal level of the received signal obtained from the loop coil without the change caused by the meandering portion that meanders through the through hole 2H. Therefore, even if the through hole 2H is provided in the effective area, the deterioration of the accuracy of the coordinates of the position indicated by the electronic pen 3 can be minimized.

[0079] Also, in the position detection circuit of the above-described embodiment, the loop coil has a detour portion that detours around the through-hole 2H, and stores the first table information for calculating the indicated position in the region within the through-hole 2H. Therefore, even if there is a position indication by the electronic pen 3 in the region within the through-hole 2H, as described above, the indicated position by the electronic pen 3 can be detected.

[0080] Note that the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 are not limited to a single turn, and may be wound a plurality of times.

[0081] [Second Embodiment of the Position Detection Sensor] In the above-described first embodiment, as described above, the loop coil straddling the through-hole 2H is configured to form a detour portion that detours around the through-hole 2H so as to draw the shortest path by a linear conductor. Therefore, the area surrounded by the loop is different from that of other loop coils that do not straddle the through-hole 2H. For this reason, the difference in the reception signal level of the signal from the electronic pen 3 due to electromagnetic induction coupling between the loop coil straddling the through-hole 2H and the loop coil not straddling the through-hole 2H is corrected using the second table information, so as to minimize the variation in the detection accuracy of the position indicated by the electronic pen 3 within the effective area of the position detection sensor 2.

[0082] However, if the difference in the area surrounded by the loop between the loop coil straddling the through-hole 2H and other loop coils not straddling the through-hole 2H is zero, correction using the second table information becomes unnecessary. Also, if the difference in the area surrounded by the loop between the loop coil straddling the through-hole 2H and other loop coils not straddling the through-hole 2H can be made smaller, the correction using the second table information will be in accordance with the small difference, so the accuracy of position detection is improved.

[0083] In the second embodiment described below, by devising the shape of the loop coil spanning the through-hole 2H of the position detection sensor 2, it is possible to cancel out or reduce the change in area due to the detour portion of the through-hole 2H, eliminating the need for correction using the second table information described above, or minimizing the correction using the second table information to improve the accuracy of position detection.

[0084] FIG. 6(A) shows one X-axis direction loop coil 21A spanning the through-hole 2H formed in the insulating substrate 20 to explain the main part of the position detection sensor 2A of this second embodiment.

[0085] As shown in FIG. 6(A), in the position detection sensor 2A of this second embodiment, the shape of the X-axis direction loop coil 21A around the through-hole 2H of the conductor forming it compensates for the increase or decrease in the area (area decrease in the case of FIG. 6(A)) surrounded by the loop formed by the detour portion 21Aa corresponding to the detour portion 21a in the position detection sensor 2 of the first embodiment.

[0086] That is, as shown in FIG. 6(A), the conductor constituting the X-axis direction loop coil 21A is arranged to form a detour portion 21Aa that protrudes to the right with respect to the straight long side of the X-axis direction loop coil 21A and detours around the through-hole 2H around the through-hole 2H. Also, in the portions immediately before and after spanning the through-hole 2H, in order to cancel out the increase or decrease in the area of the portion surrounded by the loop coil 21A due to this detour portion 21Aa, reverse protruding portions 21Ab and 21Ac that protrude to the left, which is the opposite direction to the detour portion 21Aa, are formed so as to be deformed with respect to the straight long side of the X-axis direction loop coil 21A.

[0087] In this example, the total area of the reverse projecting portions 21Ab and 21Ac immediately before and after spanning the through-hole 2H of the X-axis direction loop coil 21A, which project to the left with respect to the straight long side of the X-axis direction loop coil 21A, is configured to be approximately equal to the area of the portion of the detouring portion 21Aa that projects to the right with respect to the straight long side of the X-axis direction loop coil 21A.

[0088] In addition, in FIG. 6(A), the reverse projecting portions 21Ab and 21Ac immediately before and after spanning the through-hole 2H of the X-axis direction loop coil 21A are formed to have the same area. However, the reverse projecting portions 21Ab and 21Ac do not necessarily need to be formed to have the same area as long as the sum of their areas is approximately equal to the area of the detouring portion 21Aa. Also, it is not essential to provide both the reverse projecting portions 21Ab and 21Ac immediately before and after spanning the through-hole 2H of the X-axis direction loop coil 21A, and only one of the reverse projecting portion 21Ab immediately before spanning the through-hole 2H of the X-axis direction loop coil 21A or the reverse projecting portion 21Ac immediately after it may be provided.

[0089] FIG. 6(A) shows only one X-axis direction loop coil 21A in the second embodiment, and illustration of the Y-axis direction loop coil 22A in the second embodiment is omitted. However, for the Y-axis direction loop coil 22A as well, by providing reverse projecting portions immediately before and / or after spanning the through-hole 2H so that the area is approximately equal to the area of its detouring portion 22Aa (illustration omitted), it is configured in the same manner as the X-axis direction loop coil 21A.

[0090] In addition, also in the position detection sensor 2A of this second embodiment, when the arrangement pitches τx and τy of the X-axis direction loop coil 21 and the Y-axis direction loop coil 22 are smaller than the horizontal length Lx and the vertical length Ly of the through-hole 2H, a plurality of X-axis direction loop coils 21 and Y-axis direction loop coils 22 spanning the through-hole 2H are provided.

[0091] FIG. 6(B) shows an example of the arrangement pattern of a plurality of X-axis direction loop coils 21A and Y-axis direction loop coils 22A spanning the through-hole 2H in the position detection sensor 2A of this second embodiment. This FIG. 6(B) is a figure corresponding to FIG. 5 of the position detection sensor 2 of the first embodiment described above. In this FIG. 6(B), parts similar to those of the position detection sensor 2 of the first embodiment shown in FIG. 5 are denoted by the same reference numerals, and the description thereof is omitted.

[0092] In the example of this FIG. 6(B), one long side of each of the four X-axis direction loop coils 211A, 212A, 213A, and 214A spans the through-hole 2H, and one long side of the two Y-axis direction loop coils 221A and 222A spans the through-hole 2H.

[0093] And in the example of FIG. 6(B), on the straight conductors of one long side of the two left-side X-axis direction loop coils 211A and 212A out of the four X-axis direction loop coils 211 to 214, detour portions 211Aa and 212Aa that project to the left so as to bypass the left side of the through-hole 2H are formed. In this example, reverse projecting portions 211Ab and 212Ab that project to the right are formed immediately before and / or immediately after spanning the through-hole 2H. In this case, as shown in the figure, the reverse projecting portion 211Ab projects more than the reverse projecting portion 212Ab.

[0094] Also, on the straight conductors of one long side of the two right-side X-axis direction loop coils 213A and 214A, detour portions 213Aa and 214Aa that project to the right so as to bypass the right side of the through-hole 2H are formed. In this example, reverse projecting portions 213Ab and 214Ab that project to the left are formed immediately before and / or immediately after spanning the through-hole 2H. In this case, as shown in the figure, the reverse projecting portion 214Ab projects more than the reverse projecting portion 213Ab.

[0095] Also, in the case of the example of FIG. 6(B), on the straight conductor on one side of the long side of the upper Y-axis direction loop coil 221A among the two Y-axis direction loop coils 221A and 222A, a detour portion 221Aa that protrudes upward so as to bypass the upper side of the through hole 2H is formed. In this example, an inverted protruding portion 221Ab that protrudes downward is formed immediately before and / or immediately after crossing the through hole 2H. Further, on the straight conductor on one side of the long side of the lower Y-axis direction loop coil 222A, a detour portion 222Aa that protrudes downward so as to bypass the lower side of the through hole 2H is formed. In this example, an inverted protruding portion 222Ab that protrudes upward is formed immediately before and / or immediately after crossing the through hole 2H.

[0096] As shown in FIG. 6(B), in the plurality of X-axis direction loop coils 211A to 214A and Y-axis direction loop coils 221A and 222A, since it is necessary to configure the inverted protruding portions so that the conductors do not contact each other, it is difficult for each inverted protruding portion to have the same area as the areas of the respective detour portions 21Aa and 22Aa. Therefore, in such a case, for each of the plurality of X-axis direction loop coils 21A (211A to 214A) and Y-axis direction loop coils 22A (221A and 222A) crossing the through hole 2H, the correction by the above-described second table information is used together. However, as described above, the value of the correction value of the second table information in the case of the position detection sensor 2A of the second embodiment can be made smaller than that of the first embodiment, and the accuracy of position detection is improved as described above.

[0097] As described above, in the position detection sensor 2A of the second embodiment, an inverted protruding portion is formed on the loop coil crossing the through hole 2H so as to compensate for the increase or decrease in the area of the portion surrounded by the detour portion that bypasses the through hole. Therefore, the difference in area between the loop coil crossing the through hole 2H and the loop coil not crossing the through hole 2H can be eliminated or reduced. As a result, the correction by the second table information can be omitted, or the correction value by the second table information can be made smaller to more effectively suppress the deterioration of the position detection accuracy.

[0098] Note that also in this second embodiment, generating and storing the first table information and performing position detection when the area within the through hole 2H is indicated by the electronic pen are the same as those described in the first embodiment.

[0099] Note that the X-axis direction loop coil 21A and the Y-axis direction loop coil 22A are not limited to a single turn, and may be wound a plurality of times.

[0100] [Third Embodiment of the Position Detection Sensor] In the third embodiment as well, by devising the shape of the loop coil straddling the through hole 2H of the position detection sensor 2, it is possible to cancel out or reduce the area change due to the detour portion of the through hole 2H, so that correction using the second table information described above is unnecessary, or the correction using the second table information is minimized to improve the accuracy of position detection.

[0101] In the position detection sensors 2 and 2A of the first embodiment and the second embodiment described above, the X-axis direction loop coils 21 and 21A and the Y-axis direction loop coils 22 and 22A are not limited to a single turn. Even when wound a plurality of times, the detour portions 21a and 21Aa of the through hole 2H and the detour portions 22a and 22Aa are formed so that all loop conductor portions project in the same direction.

[0102] However, when the number of turns of the X-axis direction loop coil and the Y-axis direction loop coil is an even number, by forming the detour portions such that the two halves of the even number of turns project in different directions, it is possible to eliminate or reduce the difference in the area occupied by the loop shape between the loop coil straddling the through hole and the loop coil not straddling the through hole.

[0103] Figs. 7(A) and (B) show one of the X-axis direction loop coils 21B straddling the through-hole 2HB formed in the insulating substrate 20 in order to explain the main part of the position detection sensor 2B of this third embodiment. In the position detection sensor 2B of the example in Fig. 7(A), the X-axis direction loop coil 21B and the Y-axis direction loop coil 22B (not shown) are each configured to be wound twice. And in the example of Fig. 7(A), the shape of the through-hole 2HB is a circular shape in which a straight line passing through the center is the axis of line symmetry.

[0104] In the example shown in Fig. 7(A), when the linear X-axis direction loop coil 21B does not bypass the through-hole 2HB, it is arranged so as to pass through the center of the circular through-hole 2HB.

[0105] And, for example, the conductor of the first winding portion 21B1, which is half of the two-wound X-axis direction loop coil 21B, is arranged along the left side of the through-hole 2HB as shown in Fig. 7(A) to form a shortest path bypass portion 21B1a along the through-hole 2HB. The conductor of the remaining half, the second winding portion 21B2, is arranged along the right side of the through-hole 2HB as shown in Fig. 7(A) to form a shortest path bypass portion 21B2a along the through-hole 2HB.

[0106] In the case of Fig. 7(A), when the X-axis direction loop coil 21B does not bypass, its linear conductor straddles the through-hole 2HB in a state where it passes through the center position of the circular through-hole 2HB. Therefore, the bypass portions 21B1a and 21B2a bypass a semicircular circumference of the through-hole 2HB symmetrically with respect to the linear conductor of the X-axis direction loop coil 21B. For this reason, the area where each of the bypass portions 21B1a and 21B2a projects to the left and right with respect to the linear conductor of the X-axis direction loop coil 21B is approximately equal to the area of the semicircular region of the through-hole 2HB. And due to the bypass portion 21B1a, the area of the first winding portion 21B1 increases, and due to the bypass portion 21B2a, the area of the second winding portion 21B2 decreases, and they cancel each other out in terms of area increase and decrease.

[0107] As described above, in this embodiment, in the double-wound X-axis direction loop coil 21B straddling the through hole 2HB and having the detour portions 21B1a and 21B2a, in the region outside the peripheral region of the through hole 2HB (corresponding to the region of the correction target range described above), the electromotive force generated by electromagnetic induction due to the electromagnetic energy from the electronic pen 3 is as shown by the curve E0 in FIG. 7(B).

[0108] And within the correction target range, the electromotive force generated by electromagnetic induction due to the electromagnetic energy from the electronic pen 3 is such that the electromotive force generated by electromagnetic induction in the first winding portion 21B1 having the detour portion 21B1a among the double-wound X-axis direction loop coils 21B is as shown by the curve E1 in FIG. 7(C), and the electromotive force generated by electromagnetic induction in the second winding portion 21B2 having the detour portion 21B2a is as shown by the curve E2 in FIG. 7(C).

[0109] Therefore, the electromotive force generated by electromagnetic induction in the X-axis direction loop coil 21B straddling the through hole 2HB, which consists of the first winding portion 21B1 and the second winding portion 21B2, is an electromotive force as shown by the broken line E3 obtained by synthesizing the electromotive force shown by the curve E1 and the electromotive force shown by the curve E2 in FIG. 7(C), and is almost equal to the electromotive force shown by the curve E0 (the electromotive force shown in FIG. 7(B)) generated by electromagnetic induction in the double-wound X-axis direction loop coil 21B in the region outside the peripheral region of the through hole 2HB (corresponding to the region of the correction target range described above) shown in FIG. 7(B).

[0110] Therefore, when the double-wound X-axis direction loop coil 21B straddles the through hole 2HB in the state shown in FIG. 7(A), correction by the first table information for the electromotive force induced in the X-axis direction loop coil 21B becomes unnecessary.

[0111] However, when the X-axis direction loop coil 21B crosses the through hole 2HB at a position where the extending direction of its linear conductor is deviated from the state of passing through the center position of the circular through hole 2HB, a difference occurs between the area of the protruding portion of the detour portion 21B1a and the area of the protruding portion of the detour portion 21B2a. In that case, it is better to execute the correction based on the first table information for the electromotive force induced in the X-axis direction loop coil 21B.

[0112] Although illustration and description of the Y-axis direction loop coil 22B are omitted, the situation is the same.

[0113] Note that, by making the protruding directions of the detour portions that bypass the through hole different between the first winding portion and the second winding portion of the double-wound loop coil, the canceling effect of the increase and decrease in the area of the protruding portion is large when the loop coil crosses near the center of the through hole. For a loop coil that crosses the through hole at the peripheral portion of the shape of the through hole, it is better to arrange it to bypass along the shortest path along the shape of the through hole as in the first embodiment or the second embodiment, which can instead reduce the change in the area of the loop coil that does not cross the through hole.

[0114] For example, when the double-wound X-axis direction loop coil 21B is arranged at an arrangement pitch τx, as shown in FIG. 7(D), the case where three X-axis direction loop coils 21B (distinguished as 211B, 212B, and 213B in FIG. 7(D)) cross the through hole 2HB will be described as an example.

[0115] In the example of FIG. 7(D), among the three X-axis direction loop coils 211B, 212B, and 213B spanning the through-hole 2HB, the central X-axis direction loop coil 212B is in a state where the extension direction of its linear conductor passes through the center position of the circular through-hole 2HB. And for the other X-axis direction loop coils 211B and 213B, the extension direction of their linear conductors does not pass through the center position of the circular through-hole 2HB, and the change in the area of the X-axis direction loop coils 211B and 213B that span the through-hole 2HB and those that do not span it is smaller than the change in the area of the X-axis direction loop coils 211B and 213B when the overhanging direction of the bypass portion that bypasses the through-hole 2HB is made different between the first winding portion and the second winding portion of the double-wound X-axis direction loop coils 211B and 213B. They are arranged in a state where it is smaller when a bypass portion that bypasses along the shortest path along the shape of the through-hole 2HB is provided.

[0116] Considering that the three X-axis direction loop coils 211B, 212B, and 213B are spanning the through-hole 2HB in the above positional relationship, in the example of FIG. 7(D), the first winding portion 212B1 of the central X-axis direction loop coil 212B is arranged with a bypass portion 212B2a formed so as to protrude to the left, and the second winding portion 212B2 is arranged with a bypass portion 212B2a formed so as to protrude to the right, so that the overhanging direction of the bypass portion that bypasses the through-hole 2HB is made different.

[0117] Also, in the example of FIG. 7(D), the first winding portion 211B1 and the second winding portion 211B2 of the left X-axis direction loop coil 211B are arranged with bypass portions 211B1a and 211B2a formed to bypass the left side along the shortest path along the circular shape of the through-hole 2HB. Further, in the example of FIG. 7(D), the first winding portion 213B1 and the second winding portion 213B2 of the right X-axis direction loop coil 213B are arranged with bypass portions 213B1a and 213B2a formed to bypass the right side along the shortest path along the circular shape of the through-hole 2HB.

[0118] Regarding the first winding portion 211B1 and the second winding portion 211B2 of the X-axis direction loop coil 211B, and the first winding portion 213B1 and the second winding portion 213B2 of the X-axis direction loop coil 213B, it is of course possible to configure them to form reverse overhanging portions that cancel out the area change of the detour portion, which is the overhanging portion, as in the above-described second embodiment.

[0119] In the position detection circuit corresponding to the position detection sensor 2B in the example of FIG. 7(D), among the three X-axis direction loop coils 211B, 212B, and 213B spanning the through-hole 2HB, for the central X-axis direction loop coil 212B, the second table information is unnecessary (the second table information may be provided), and for the X-axis direction loop coils 211B and 213B, the second table information is prepared to correct their electromotive forces.

[0120] In the example of FIG. 7, the through-hole 2HB was circular, but the shape of the through-hole 2HB formed in the position detection sensor 2B of the third embodiment may be any shape. However, when the shape of the through-hole 2HB has a symmetry axis of line symmetry, when the extension direction of the linear conductor of the loop coil overlaps with the symmetry axis of the through-hole 2HB, the areas of the overhanging portions formed by the respective detour portions with different overhanging directions on the left and right or up and down can be made equal by utilizing this. However, even for a through-hole 2HB having such a shape without a line symmetry axis, any shape is acceptable as long as the increase and decrease in area can be canceled by making the overhanging directions different in the left-right (array pitch direction of the X-axis direction loop coil) or up-down (array pitch direction of the Y-axis direction loop coil).

[0121] In addition, as in the example of FIG. 7(D), when a plurality of loop coils are wound around the through hole 2HB, for each of the plurality of loop coils, as shown in FIG. 7(A), a detour portion is formed so that the area increases for the first winding portion, and a detour portion is formed so that the area decreases for the second winding portion. When trying to form the detour portions on the same surface of the insulating substrate, a part of the detour portions of each other intersects. Therefore, in order to avoid the intersection of the detour portions, conductors are provided on both the front and back surfaces of the insulating substrate using through holes also in the detour portions.

[0122] The example of FIG. 7 described above is for the case of a loop coil wound twice, but the number of turns of the loop coil formed in the position detection sensor 2B of the third embodiment can be even and divisible by two so that the overhanging directions can be made different in the left - right (the array pitch direction of the X - axis direction loop coils) or up - down (the array pitch direction of the Y - axis direction loop coils), and of course, it may be 2 or more.

[0123] Note that also in this third embodiment, generating and storing the first table information and performing position detection when the area in the through hole 2HB is indicated by the electronic pen is the same as described in the first embodiment.

[0124] [Fourth Embodiment of the Position Detection Sensor] The fourth embodiment is an example in which, by devising the loop coil wound around the through hole 2H of the position detection sensor 2, the area change due to the detour portion of the through hole 2H can be made as small as possible, minimizing the correction by the first table information, and improving the accuracy of position detection.

[0125] In the sensor for position detection of this example, as described above, the X-axis direction loop coil and the Y-axis direction loop coil are arranged on the insulating substrate by laying a linear conductor with a predetermined width in a rectangular shape, for example. As described above, since the conductor constituting the loop coil has a predetermined width, a region corresponding to the width is required when bypassing the through hole. In particular, when the loop coil is formed as a multi-turn coil, they are arranged close to each other even in the bypass portion while maintaining electrical insulation from each other. However, the larger the width of the conductor, the larger the area changed by the bypass portion.

[0126] In view of this point, in the fourth embodiment, the width of the conductor in the bypass portion of the through hole of the loop coil spanning the through hole is made smaller than the width of the conductor in other portions, so as to suppress as much as possible the size of the area changed by the bypass portion.

[0127] FIG. 8 is a diagram for explaining a bypass portion formed in the X-axis direction loop coil 21C spanning the through hole 2HC formed in the effective region of the insulating substrate of the position detection sensor 2C of this fourth embodiment. In this example, the X-axis direction loop coil 21C is a two-turn loop coil, and is composed of a first turn portion 21C1 and a second turn portion 21C2. Further, the through hole 2HC has a circular shape as in the third embodiment. Note that the shape of the through hole 2HC is not limited to a circular shape, and may be any shape, as in the previous example.

[0128] As shown in FIG. 8, in this fourth embodiment, bypass portions 21C1a and 21C2a that bypass the through hole 2HC along the shortest path are formed in the first turn portion 21C1 and the second turn portion 21C2 of the X-axis direction loop coil 21C. And in this embodiment, the widths of the conductors in the portions of the first turn portion 21C1 and the second turn portion 21C2 of the X-axis direction loop coil 21C excluding the bypass portions 21C1a and 21C2a are set to a predetermined width d0, and the widths of the conductors in the bypass portions 21C1a and 21C2a are smaller than the width d0, and are set to the minimum width d1 (<d0) for forming the X-axis direction loop coil 21C.

[0129] As a result, the detour portions 21C1a and 21C2a can be positioned closer to the periphery of the through hole 2HC than when the width of the conductor of the X-axis direction loop coil 21C is the width d0. Therefore, the lengths by which the detour portions 21C1a and 21C2a protrude are reduced, and the area of the protruding portions is also reduced. Accordingly, the difference in area between the loop coil spanning the through hole 2HC and the loop coil not spanning the through hole 2HC can be reduced, and the correction value based on the second table information can be reduced, so that there is an effect that deterioration of the position detection accuracy can be further suppressed.

[0130] In addition, in the position detection sensor 2C of this fourth embodiment as well, the above-described second embodiment and third embodiment can be applied. That is, when the second embodiment is applied to the fourth embodiment, the width of the conductor of the reverse protruding portion and the detour portion is made thinner, or the width of the conductor of the detour portion is made thinner without changing the width of the conductor of the reverse protruding portion. Further, when the third embodiment is applied to the fourth embodiment, when the loop coil is wound twice, the width of the conductor of the detour portion of the first winding portion and the width of the conductor of the detour portion of the second winding portion are made thinner.

[0131] In the above description, an example of a loop coil wound a plurality of times has been described, but this is because the effect of the example of FIG. 8 can be obtained more greatly. Needless to say, the effect that the magnitude of the change in area can be reduced can also be obtained for a single-wound loop coil.

[0132] In addition, also in this fourth embodiment, generating and storing the first table information and performing position detection when the region in the through hole 2HC is indicated by the electronic pen is the same as that described in the first embodiment.

[0133] [Other Embodiments and Modification Examples] <Regarding the First Table Information and the Second Table Information for Correction of Position Detection> The second table memory provided in the position detection circuit in the above-described first to fourth embodiments and the first table information and the second table information stored in each of the second table memories are generally formed assuming that the electronic pen 3 is perpendicular to the input surface (upper surface of the surface panel 13) of the position detection sensor.

[0134] However, in a normal usage mode, as shown in FIG. 9(A), the electronic pen 3 is used in a state inclined at a predetermined angle θ with respect to the input surface (surface of the surface panel 13) of the position detection sensor. And in such an inclined usage state, depending on the direction in which the electronic pen 3 is inclined, the loop coil for which the output signal is used for detecting the indicated position by the electronic pen 3 in the position detection sensor changes.

[0135] Therefore, it is better to prepare the first table information and the second table information according to the tilt angle θ and the tilt direction φ of the electronic pen 3 respectively, which will lead to an improvement in the accuracy of position detection. Therefore, for example, a plurality of predetermined tilt angles θ and a plurality of tilt directions φ of the electronic pen 3 are determined, and the first table information and the second table information corresponding to each tilt angle θ and tilt direction φ are generated and associated with each tilt angle θ and tilt direction φ, and stored in the first table memory and the second table memory.

[0136] FIG. 9(B) is a diagram showing four cases as a plurality of tilt directions φ at a certain tilt angle θ1. That is, as shown by the arrow in FIG. 9(B), in the input surface (surface of the surface panel 13) of the position detection sensor, the direction from the bottom to the top is defined as the 0-degree direction. And with respect to this 0-degree direction, the angle shifted to the right is defined as the + angle, and the angle shifted to the left is defined as the - angle. As shown in FIG. 9(B), this example defines four directions of φ1 = +45 degrees, φ2 = -45 degrees, φ3 = +135 degrees, and φ4 = -135 degrees. Then, the first table information and the second table information at each tilt direction angle φ1, φ2, φ3, φ4 are generated and associated with the tilt angle θ1, and stored in the first table memory and the second table memory.

[0137] Then, regarding the tilt angle θ of the electronic pen 3, a plurality of values such as θ1, θ2, θ3... are set. In each state of the tilt angles θ1, θ2, θ3..., the first table information and the second table information are generated for the tilt direction angles φ1, φ2, φ3, φ4, and are stored in the first table memory and the second table memory in association with each tilt angle θ1, θ2, θ3.... When the tilt angle θ = 90 degrees, since it is not necessary to consider the tilt direction angles φ1, φ2, φ3, φ4, the first table information and the second table information can be single, and the first table information and the second table information regarding the tilt direction angles φ1, φ2, φ3, φ4 are not required.

[0138] On the other hand, the electronic pen 3 is provided with means for detecting the tilt angle θ and the tilt direction φ, and the position detection circuit is provided with a detection function for the tilt angle θ and the tilt direction φ of the electronic pen 3. Since well-known techniques can be used for the means for detecting the tilt angle θ and the tilt direction φ of the electronic pen 3 and the detection function of the tilt angle θ and the tilt direction φ of the electronic pen 3 in the position detection circuit, the description of its configuration is omitted here.

[0139] Then, during actual use, the position detection circuit detects the tilt angle θ and the tilt direction φ of the electronic pen 3, and performs correction processing using the first table information and the second table information corresponding to the detected tilt angle θ and tilt direction φ. In this case, when the tilt angle θ and the tilt direction φ of the electronic pen 3 detected by the position detection circuit are between the angles for which the first table information and the second table information are prepared in advance, interpolation processing can be performed according to the detected angle using the first table information and the second table information of the two angles with the detected angle as the middle, thereby enabling correction.

[0140] <Example in the case of the electrostatic coupling method> The above embodiments are for an electromagnetic induction type electronic pen, a position detection sensor, and a position detection circuit. However, the present invention is not limited to the electromagnetic induction method and is also applicable to an electrostatic coupling type electronic pen, a position detection sensor, and a position detection circuit.

[0141] FIG. 10 is a diagram for explaining a configuration example of an electrostatic coupling type electronic pen 3D, a position detection sensor 2D, and a position detection circuit 100D in this example.

[0142] The electronic pen 3D includes a signal transmission circuit 30S that transmits a predetermined signal, and includes a conductive core 34. The signal from the signal transmission circuit 30S is supplied from the core 34 to the position detection sensor 2D by electrostatic coupling.

[0143] In this example, the position detection sensor 2D is configured such that a first conductor group 24 is formed on the back side of an insulating substrate 20D having a through hole 2HD, and a second conductor group 25 is formed on the front side. The through hole 2HD is provided within an effective region for position detection formed by the first conductor group 24 and the second conductor group 25. The first conductor group 24 is, for example, a plurality of first linear conductors 24Y1, 24Y2,..., 24Y m (m is an integer of 1 or more) arranged in parallel at a predetermined interval in the vertical direction (Y-axis direction). And the first linear conductor 24Y spanning the through hole 2HD is arranged so as to form a detour portion that detours the through hole 2HD by any one of the above-described first to fourth embodiments, or a combination thereof.

[0144] Also, the second conductor group 25 is in a direction intersecting the extending direction of the first linear conductors 24Y1, 24Y2,..., 24Y m In this example, a plurality of second linear conductors 25X1, 25X2,..., 25X extending in the vertical direction (Y-axis direction) orthogonal to the extending direction n(n is an integer of 1 or more) are arranged in parallel at a predetermined interval from each other and disposed in the X-axis direction. And the second linear conductor 25X spanning the through hole 2HD is disposed so as to form a detour portion that detours the through hole 2HD by any one of the above-described first to fourth embodiments or a combination thereof.

[0145] The position detection sensor 2D in this example is configured such that an effective area having a size corresponding to the size of the display area of the display screen is used as an instruction input surface on the display screen of a display device such as an LCD of an electronic device, and the first conductor group 211 and the second conductor group 212 are formed to have light transmissibility. Note that the first linear conductor 24Y and the second linear conductor 25X constitute position detection electrodes.

[0146] Note that the first conductor group 24 and the second conductor group 25 may be each disposed on the same surface side of the insulating substrate 20D.

[0147] The position detection circuit 100D includes a selection circuit 121 that serves as an input / output interface with the position detection sensor 2D, an amplification circuit 122, a band-pass filter 123, a detection circuit 124, a sample-and-hold circuit 125, an AD (Analog to Digital) conversion circuit 126, and a processing control circuit 130.

[0148] The selection circuit 121 selects one conductor from each of the first conductor group 24 and the second conductor group 25 based on a control signal from the processing control circuit 130. The conductor selected by the selection circuit 121 is connected to the amplification circuit 122, and a signal from the electronic pen 3D is detected by the selected conductor and amplified by the amplification circuit 122. The output of this amplification circuit 122 is supplied to the band-pass filter 123, and only the frequency component of the signal transmitted from the electronic pen 3D is extracted.

[0149] The output signal of the band - pass filter 123 is detected by the detection circuit 124. The output signal of this detection circuit 124 is supplied to the sample - hold circuit 125, sample - held at a predetermined timing by the sampling signal from the processing control circuit 130, then converted into a digital value by the AD conversion circuit 126, and supplied to the processing control circuit 130.

[0150] The processing control circuit 130 sends control signals to the sample - hold circuit 125, the AD conversion circuit 126, and the selection circuit 121 respectively, calculates the position coordinates on the position - detection sensor 2D indicated by the electronic pen 3D from the digital data from the AD conversion circuit 226, and outputs the data of the position coordinates to, for example, other processing processors and the like.

[0151] And also in this example, the processing control circuit 130 corrects the outputs from the first linear conductor 24Y and the second linear conductor 25X spanning the through - hole 2HD, and includes a correction circuit 131 that performs processing for detecting the indicated position when the region within the through - hole 2HD is indicated by the electronic pen 3D. And a first table memory 132 that stores first table information for performing correction processing of the outputs from the first linear conductor 24Y and the second linear conductor 25X spanning the through - hole 2HD with respect to this correction circuit 131, and a second table memory 133 that stores second table information for detecting the indicated position of the region within the through - hole 2HD are provided in the processing control circuit 130.

[0152] With this configuration, in the processing control circuit 130, even when using the position - detection sensor 2D in the example of FIG. 10 having the through - hole 2HD in the same manner as the processing control circuit 110 in the above - described first to fourth embodiments, the indicated position by the electronic pen 3D within the effective region including the through - hole 2HD can be detected without problems.

[0153] [Other Modification Examples] In the above-described embodiment, the case where the position detection electrode is formed by a linear conductor has been described. However, for example, even when the insulating substrate has a circular or elliptical shape and the position detection electrode is formed in a curved shape, and through holes are formed within the effective region of the circular or elliptical insulating substrate, the present invention is applicable.

Explanation of Reference Numerals

[0154] 1... Electronic device, 2, 2A, 2B, 2C, 2D... Position detection sensor, 2H, 2HB, 2HC, 2HD... Through hole, 3, 3D... Electronic pen, 23... Through hole, 21a, 22a... Detour portion

Claims

1. An electronic device in which a position detection sensor is disposed inside a housing, a display screen is provided on the operation input surface side with respect to the position detection sensor, and a predetermined component is disposed on the back side of the position detection sensor on the side opposite to the operation input surface, wherein the position detection sensor is a position detection sensor in which position detection electrodes configured as a plurality of loop coils are disposed on an insulating substrate, and a region where the plurality of position detection electrodes are disposed is an effective detection region for detecting an input instruction on the display screen for detecting the position of a position indicator, a predetermined through-hole having a predetermined shape corresponding to the predetermined component is formed in the position detection sensor at a position corresponding to the position of the predetermined component within the effective detection region, the position detection electrodes are disposed so as to bypass the through-hole along the shape of the through-hole at a portion spanning the through-hole, an image for notifying that a position is an operation position for the predetermined component is displayed on the display screen at a position corresponding to the position of the predetermined component The electronic device is characterized by the above.

2. In the position detection sensor, the position detection electrode spanning the through-hole is formed with the shape around the through-hole of the conductor being deformed so as to compensate for an increase or decrease in the area of a portion surrounded by the loop coil due to the conductor bypassing the through-hole The electronic device according to claim 1, characterized by the above.

3. In the position detection sensor, the position detection electrode spanning the through-hole is deformed so as to reduce a change in the area of a portion surrounded by the loop coil due to deformation caused by the conductor bypassing the through-hole at a portion immediately before and / or immediately after spanning the through-hole The position detection sensor according to claim 1, characterized by the above.

4. The electronic device includes a position detection device unit that detects a position indicated through the display screen by the position indicator based on signals from the plurality of position detection electrodes of the position detection sensor, the position detection device unit includes a correction circuit that corrects a signal from the position detection electrode spanning the through-hole The electronic device according to claim 1, characterized by the above.

5. The electronic device includes a position detection device unit that detects a position indicated through the display screen by the position indicator based on signals from the plurality of position detection electrodes of the position detection sensor, The position detection device unit includes a position correction circuit for detecting a position indicated through the operation input surface by the position indicator in the vicinity of the through hole and within the through hole. The electronic device according to claim 1, characterized in that.

6. In the position detection sensor, the plurality of position detection electrodes are arranged in a predetermined direction with a predetermined array pitch. The size of the through hole is larger than the predetermined array pitch. The electronic device according to claim 1, characterized in that.

7. In the position detection sensor, a portion where the position detection electrode bypasses the through hole is configured such that the length of the bypass path is the shortest. The electronic device according to claim 1, characterized in that.

8. In the position detection sensor, a plurality of adjacent position detection electrodes are arranged to be close to each other regardless of the array pitch in a portion where they bypass the through hole in the same bypass path. The electronic device according to claim 6, characterized in that.

9. The position detection sensor detects a coordinate position in a first direction and a coordinate position in a second direction orthogonal to the first direction in the effective detection region, and the position detection electrode includes a first direction electrode for detecting the coordinate position in the first direction arranged in a plurality in the second direction and a second direction electrode for detecting the coordinate position in the second direction arranged in a plurality in the first direction. The first direction electrode and the second direction electrode are formed by disposing conductors on both surfaces of the insulating substrate. The electronic device according to claim 1, characterized in that.

10. A magnetic shielding material is provided for the position detection sensor in addition to the insulating substrate. The electronic device according to claim 1, characterized in that.

11. An electromagnetic shielding material is provided for the position detection sensor in addition to the insulating substrate. The electronic device according to claim 1, characterized in that.

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