Sensor

Abstract

[Problem] To reduce magnetic coupling that occurs between a lead line and each coil without obliquely forming first and second coils. [Solution] A sensor according to the present invention comprises: a plurality of coils that include a plurality of first coils, each of which extends in the X direction, and a plurality of second coils, each of which extends in the Y direction; terminal groups 40a to 40c that include a plurality of internal terminals which are provided so as to correspond to one end and the other end of each of the plurality of coils; and a plurality of lead lines 42x, 42y, via each of which one of the plurality of internal terminals is connected to one corresponding end or the other corresponding end of the plurality of coils. The plurality of lead lines 42x, 42y each extend along one of one or more directions that obliquely intersect with the X and Y directions.

Description

[Technical Field]

[0001] The present invention relates to a sensor, and more particularly to a sensor that is used by being superimposed on a display device. [Background technology]

[0002] A position detection device is known that detects the position of a position indicator by using a sensor to detect an alternating magnetic field emitted from the position indicator. Specific methods of this type of position detection device are the EM method, which requires a battery to be installed in the position indicator, and the EMR (registered trademark) method, which generates power in the position indicator using electromagnetic waves emitted by the position detection device via the sensor. In the EM method, electromagnetic waves are transmitted only from the position indicator to the position detection device, while in the EMR (registered trademark) method, electromagnetic waves are transmitted and received in both directions.

[0003] The sensor of a position detection device is generally composed of a collection of multiple first coils (loop electrodes), each extending in a thin strip in the direction of the long side of the detection area, and multiple second coils (loop electrodes), each extending in a thin strip in the direction of the short side of the detection area.

[0004] Patent Document 1 discloses an example of a position detection sensor having such first and second coils. In this example, the connection points between each coil and its corresponding lead wire are located in the center of the detection area rather than at the edge, and each lead wire extends within the detection area, thereby minimizing the invalid area that occurs outside the detection area. Patent Document 2 also discloses an example of a position detection sensor in which each of the first and second coils is formed obliquely. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 4405247 [Patent Document 2] International Publication No. 2019 / 171511 Summary of the Invention [Problem to be solved by the invention]

[0006] In Patent Document 1, the lead wires extend parallel to the coils. With this configuration, large magnetic coupling occurs between the lead wires and each coil, which can cause a signal flowing through one to be superimposed on the other. If the first and second coils described in Patent Document 1 were formed at an angle as in Patent Document 2, the section in which the lead wires and each coil run parallel to each other could be shortened, thereby reducing the magnetic coupling between them. However, because the first and second coils are formed at an angle, there is a problem in that coordinate conversion is required when calculating the coordinates of the pen.

[0007] Therefore, one object of the present invention is to provide a sensor that can reduce magnetic coupling that occurs between the lead wires and each coil without forming the first and second coils at an angle.

[0008] Furthermore, when forming lead wires so as to intersect obliquely with the first and second coils, two wiring layers for wiring the lead wires have conventionally been required, as shown in Patent Document 2. However, the more layers there are, the higher the manufacturing costs of the sensor become, so there has been a demand for the lead wires to be able to be wired in only one layer.

[0009] Therefore, another object of the present invention is to provide a sensor in which lead wires that obliquely intersect with the first and second coils can be wired in only one layer.

[0010] In addition, the position detection device may be configured to acquire the intensity distribution of the alternating magnetic field using two or more adjacent coils and derive the position of the position indicator based on the acquired intensity distribution. In this case, if the difference in parasitic resistance between the two or more adjacent coils is large, distortion may occur in the acquired intensity distribution, making it impossible to derive the correct position.

[0011] Therefore, another object of the present invention is to provide a sensor that enables a position detection device to correctly derive the position of a position indicator. [Means for solving the problem]

[0012] A sensor according to a first aspect of the present invention is a sensor having a plurality of coils including a plurality of first coils each extending in a first direction parallel to one side of a rectangular detection area and a plurality of second coils each extending in a second direction perpendicular to the first direction, a plurality of terminals provided corresponding to one end and the other end of each of the plurality of coils, and a plurality of lead-out wires connecting each of the plurality of terminals to one end or the other end of a corresponding one of the plurality of coils, wherein each of the plurality of lead-out wires extends along one or more directions obliquely intersecting each of the first and second directions.

[0013] A sensor according to a second aspect of the present invention is the sensor according to the first aspect of the present invention, wherein the plurality of lead-out wires are wires formed in a first wiring layer, and the plurality of lead-out wires include a plurality of first lead-out wires connected to one end or the other end of the plurality of first coils, and a plurality of second lead-out wires connected to one end or the other end of the plurality of second coils, and each of the plurality of first lead-out wires is electrically connected to one end or the other end of a corresponding one of the plurality of first coils at a first connection point provided in the first wiring layer, and each of the plurality of second lead-out wires is The sensor is electrically connected to one end or the other end of the corresponding second coils at second connection points provided in the first wiring layer, and the multiple terminals, the multiple first connection points, and the multiple second connection points are arranged so that a first region in the first wiring layer including multiple first terminals among the multiple terminals connected to the multiple first coils and the multiple first connection points does not intersect with a second region in the first wiring layer including multiple second terminals among the multiple terminals connected to the multiple first coils and the multiple second connection points.

[0014] A sensor according to a third aspect of the present invention is the sensor according to the first aspect of the present invention, wherein the arrangement of the plurality of terminals and the connection points between the plurality of lead wires and the plurality of coils, as well as the shape of each of the plurality of lead wires, are determined so that the absolute value of the moving average deviation rate of the lead wire for each of the coils is equal to or less than a predetermined value. [Effects of the Invention]

[0015] According to the first aspect of the present invention, multiple lead wires are extended along one or more directions that are oblique to each of the first and second directions, thereby making it possible to reduce magnetic coupling that occurs between the lead wires and each coil without forming the first and second coils at an angle.

[0016] According to the second aspect of the present invention, the first region in which the multiple first lead lines extend and the second region in which the multiple second lead lines extend do not intersect, so that it is possible to wire the lead lines that intersect obliquely with the first and second coils in only one layer.

[0017] According to the third aspect of the present invention, it is possible to avoid large differences in parasitic resistance between two or more adjacent coils, thereby enabling the position detection device to correctly derive the position of the position indicator. [Brief explanation of the drawings]

[0018] [Figure 1] 1 is an exploded view of a tablet terminal 1 according to an embodiment of the present invention. [Figure 2] 1(a) is a side view of the tablet terminal 1, and FIG. 1(b) is a rear view of the tablet terminal 1. FIG. [Figure 3] FIG. 2 is a schematic cross-sectional view of the sensor 13 shown in FIG. [Figure 4] 10 is a diagram showing the configuration of wiring included in a wiring layer L1 of the sensor 13. FIG. [Figure 5] 10 is a diagram showing the configuration of wiring included in a wiring layer L2 of the sensor 13. FIG. [Figure 6]10 is a diagram showing the configuration of wiring included in a wiring layer L3 of the sensor 13. FIG. [Figure 7] 5 is a diagram illustrating details of a bent portion 51 shown in FIG. 4. FIG. [Figure 8] 1 is a diagram showing an area AX in a wiring layer L1 where a plurality of lead-out lines 42x extend, and an area AY in the wiring layer L1 where a plurality of lead-out lines 42y extend. [Figure 9] (a) is a diagram plotting, for each coil 41x, the length of the corresponding lead-out wire 42x (the total length of the two corresponding lead-out wires 42x) and the moving average deviation rate of the length of the corresponding lead-out wire 42x, and (b) is a diagram plotting, for each coil 41y, the length of the corresponding lead-out wire 42y (the total length of the two corresponding lead-out wires 42x) and the moving average deviation rate of the length of the corresponding lead-out wire 42y. [Figure 10] FIG. 10 is a diagram showing the configuration of wiring included in a wiring layer L1 according to a comparative example. [Figure 11] This is a diagram in which the length of the corresponding lead wire 103 (the total length of the two corresponding lead wires 103) and the moving average deviation rate of the length of the corresponding lead wire 103 are plotted for each coil 100 shown in FIG. [Figure 12] 10 is a diagram showing the configuration of wiring included in a wiring layer L1 of a sensor 13 according to a modified example of the present embodiment. FIG. [Figure 13] 3 is a diagram showing the configuration of wiring included in a wiring layer L1 of a sensor 13 according to the first embodiment. FIG. [Figure 14] 10 is a diagram showing the configuration of wiring included in a wiring layer L1 of a sensor 13 according to a second embodiment. FIG. [Figure 15] FIG. 10 is a diagram showing the configuration of wiring included in a wiring layer L1 of a sensor 13 according to a third embodiment. [Figure 16] FIG. 10 is a diagram showing the configuration of wiring included in a wiring layer L1 of a sensor 13 according to a fourth embodiment. [Figure 17] FIG. 10 is a diagram showing the configuration of wiring included in a wiring layer L1 of a sensor 13 according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0020] Fig. 1 is an exploded view of a tablet terminal 1 according to an embodiment of the present invention. Fig. 2(a) is a side view of the tablet terminal 1, and Fig. 2(b) is a rear view of the tablet terminal 1. In Figs. 1 and 2(a), the upper side corresponds to the display surface (touch surface) of the tablet terminal 1, and the lower side corresponds to the rear surface of the tablet terminal 1.

[0021] As shown in FIGS. 1 and 2, tablet terminal 1 has a structure in which, from the rear side, a shield plate 11, a spacer 12, a sensor 13, a display panel 16, and glass 18 are layered within display module rear cover 10, which has a bathtub shape with a closed rear side. Of these, at least the sides of sensor 13 and display panel 16 are covered by a display module frame 17 for protection and fixation. Display module frame 17 is, for example, adhesive tape. Although not shown, tablet terminal 1 further includes a housing that covers the entire tablet terminal 1 (including integrated circuit 20 and bent substrate 21, described below) except for the surface of glass 18. The surface of glass 18 forms the display surface and touch surface of tablet terminal 1.

[0022] As shown in Fig. 2, an integrated circuit 20 (controller) that constitutes a position detection device together with the sensor 13 is installed on the back of the display module rear cover 10. Although not shown, in addition to the integrated circuit 20, a processor (processing circuit) that controls the entire tablet terminal 1 and is responsible for executing any application, a control circuit for the display panel 16, and the like are also installed on the back of the display module rear cover 10. Area A shown in Fig. 2(b) indicates an area where these circuits can be arranged.

[0023] The tablet terminal 1 also includes a foldable substrate 21 for connecting the integrated circuit 20 and the sensor 13. While FIGS. 1 and 2(b) show an example in which three foldable substrates 21 are used, the number of foldable substrates 21 may be one or more. Each foldable substrate 21 is a flexible printed circuit (FPC) made of, for example, a thin plastic film, and is configured to be foldable. Utilizing this property, each foldable substrate 21 is placed in the tablet terminal 1 in a folded state so as to wrap around one side of the sensor 13 and the display panel 16, as shown in FIG. 2(a). One end of each foldable substrate 21 is introduced into the display module rear cover 10 through the opening 10a in the display module rear cover 10 shown in FIG. 1 and connected to terminal groups 40a to 40c (described below) of the sensor 13. The other end of each foldable substrate 21 is connected to the integrated circuit 20 on the rear surface of the display module rear cover 10.

[0024] The sensor 13 and integrated circuit 20 constitute the above-mentioned EM-type or EMR (registered trademark)-type position detection device, which serves to detect the position of the stylus 2 (position indicator) within a predetermined detection area. The detection area is a rectangular area set to have an area slightly larger than the display area of ​​the display panel 16, and is arranged so as to overlap the entire display area. The integrated circuit 20 detects the position of the stylus 2 within the detection area by detecting the pen signal (alternating magnetic field) sent by the stylus 2 via the sensor 13. Furthermore, if the integrated circuit 20 is compatible with the EMR (registered trademark) type, it also performs processing to generate power within the stylus 2 by sending electromagnetic waves via the sensor 13. In this case, the stylus 2 uses the generated power to send the pen signal.

[0025] The display panel 16 is a display device configured using a liquid crystal display, an organic electroluminescence display, electronic paper, or the like. The specific type of the display panel 16 is not particularly limited. The specific display content of the display panel 16 is controlled by the above-mentioned processor and control circuit. Although not shown, the display panel 16 is configured to have a rectangular display area in which a plurality of pixels are arranged in a matrix, and a bezel area set around the display area. Wiring for connecting each pixel to the control circuit is arranged in the bezel area.

[0026] Sensor 13 is disposed on the rear side of display panel 16. By adopting such an arrangement, even if lead wires 42x and 42y of coils 41x and 41y are provided in the center of the detection area inside sensor 13 as described below, it is possible to avoid a reduction in visibility of display panel 16 due to the presence of lead wires 42x and 42y. Furthermore, it is possible to reduce the area (the aforementioned invalid area) in which the position of stylus 2 located around the detection area cannot be detected, thereby making it possible to reduce the bezel area.

[0027] Shield plate 11 is a magnetic material disposed on the back surface of sensor 13, and functions as an electromagnetic shield to prevent electromagnetic waves generated by sensor 13 from leaking to the back surface. Shield plate 11 also serves as a magnetic path for magnetic flux generated by sensor 13. Spacer 12 is, for example, double-sided tape, and serves to insulate between shield plate 11 and wiring provided on sensor 13, and to secure sensor 13 to shield plate 11.

[0028] 3 is a schematic cross-sectional view of the sensor 13. As shown in the figure, the sensor 13 is configured by a multilayer substrate in which, in order from the display surface side, a wiring layer L1 (first wiring layer), an insulating layer 30, a wiring layer L2 (second wiring layer), an insulating layer 31, and a wiring layer L3 (third wiring layer) are stacked. A plurality of via conductors 35 are also provided within the sensor 13. Each via conductor 35 penetrates from the wiring layer L1 to the wiring layer L3 and serves to interconnect the wiring within each of the wiring layers L1 to L3.

[0029] 4 to 6 are diagrams illustrating the configuration of wiring included in the wiring layers L1 to L3, respectively. The X-axis direction (first direction) and the Y-axis direction (second direction) illustrated in these figures are the long-side and short-side directions of the detection area described above, respectively. The rectangular area having vertices at the four coordinates (X1, Y1), (X2, Y1), (X1, Y2), and (X2, Y2) illustrated corresponds to the detection area of ​​the sensor 13. The A-axis direction (third direction) illustrated is a direction that does not coincide with either the X-axis direction or the Y-axis direction. In other words, the A-axis direction is a direction that forms a predetermined angle with the X direction that is greater than 0 degrees and less than 90 degrees. The B-axis direction (fourth direction) illustrated is also a direction that does not coincide with either the X-axis direction or the Y-axis direction. The B-axis direction is also set to intersect with the A-axis direction. Preferably, as illustrated in FIGS. 4 to 6, the A-axis direction forms an angle of 45 degrees with the X-axis direction, and the A-axis direction and the B-axis direction are set to be perpendicular to each other.

[0030] 6, a plurality of coils 41x (second coils) each extending in the Y direction are formed on the wiring layer L3. In this embodiment, an example in which 42 coils 41x are used will be described, but the number of coils 41x is not limited to 42. The coils 41x are arranged at equal intervals in the X direction with a certain amount of overlap. To enable wiring with overlap, a portion of each coil 41x is also formed on the wiring layer L1 or the wiring layer L2 through via conductors 35 indicated by black circles in the figure.

[0031] 5, a plurality of coils 41y (first coils) each extending in the X direction are formed on the wiring layer L2. In this embodiment, an example in which 24 coils 41y are used is described, but the number of coils 41x is not limited to 24. The coils 41y are arranged at equal intervals in the Y direction with a certain amount of overlap. To enable wiring with overlap, a portion of each coil 41y is also formed on the wiring layer L1 or the wiring layer L3 through via conductors 35 indicated by black circles in the figure.

[0032] 4 to 6 show an example in which each of the coils 41x and 41y has one winding, but the actual number of windings of each of the coils 41x and 41y is greater as shown in Figs. 13 to 17. For example, it is preferable that each of the coils 41x and 41y has six windings.

[0033] 5 and 6, each of the multiple coils 41x, 41y is cut at one point along the way, and a via conductor 35 is connected to each of the two end portions created by the cut. Hereinafter, the via conductor 35 (second via conductor) connected to the end of each coil 41x may be referred to as a via conductor 35x, and the via conductor 35 (first via conductor) connected to the end of each coil 41y may be referred to as a via conductor 35y.

[0034] 4, the wiring layer L1 is configured with terminal groups 40a-40c connected to the three folded substrates 21. The terminal group 40a is for connecting each coil 41y to wiring within the folded substrate 21, and is configured with a plurality of internal terminals corresponding to one end or the other end of each coil 41y. The terminal groups 40b and 40c are for connecting each coil 41x to wiring within the folded substrate 21, and are configured with a plurality of internal terminals corresponding to one end or the other end of each coil 41x.

[0035] The wiring layer L1 is provided with a plurality of lead wires 42x, 42y. The lead wires 42x (second lead wires) are wires that are provided in a one-to-one correspondence with the ends of the plurality of coils 41x and serve to connect the corresponding via conductors 35x to the corresponding internal terminals in the terminal groups 40b, 40c. The end of each via conductor 35x exposed in the wiring layer L1 forms a connection point (second connection point) between the corresponding lead wire 42x and the end of the corresponding coil 41x. Similarly, the lead wires 42y (first lead wires) are wires that are provided in a one-to-one correspondence with the ends of the plurality of coils 41y and serve to connect the corresponding via conductor 35y to the corresponding internal terminals in the terminal group 40a. The end of each via conductor 35y exposed in the wiring layer L1 forms a connection point (first connection point) between the corresponding lead wire 42y and the end of the corresponding coil 41y.

[0036] Here, a specific method for detecting the position of the stylus 2 by the integrated circuit 20 will be described. The integrated circuit 20 first detects the potential difference between the two corresponding lead wires 42x for each of the multiple coils 41x in sequence. The detected potential difference represents the reception strength of the pen signal transmitted by the stylus 2. The integrated circuit 20 selects the coil 41x with the highest detected reception strength and a predetermined number of coils 41x located nearby, and derives the intensity distribution of the pen signal in the X direction based on the reception strength of the pen signal detected for each. The integrated circuit 20 then derives the position of the peak of the distribution and acquires it as the X coordinate of the stylus 2. The integrated circuit 20 performs similar processing in the Y direction to derive the Y coordinate of the stylus 2, and outputs the derived set of X and Y coordinates to the above-mentioned processor.

[0037] So far, we have explained the outline of the tablet terminal 1 according to this embodiment. Next, we will explain in detail the parts of the configuration of the tablet terminal 1 that constitute the features of the present invention. The parts that constitute the features of the present invention are particularly shown in Figure 4, and Figure 4 shows three parts that constitute the features of the present invention, so below we will explain these three features one by one in order with reference to Figure 4.

[0038] The first feature is that each of the plurality of lead wires 42x, 42y, with some exceptions, extends along either direction A or direction B. This prevents the lead wires 42x, 42y and the coils 41x, 41y from running parallel to each other in most of the plurality of lead wires 42x, 42y, so that it is possible to reduce magnetic coupling occurring between each of the plurality of lead wires 42x, 42y and the plurality of coils 41x, 41y without forming the coils 41x, 41y at an angle.

[0039] The exceptions are connection portion 50 with terminal groups 40a to 40c, bent portion 51, and connection portion 52 with via conductors 35x and 35y shown in Fig. 4. Note that in Fig. 4, due to space limitations, only one reference numeral is assigned to each of connection portion 50, bent portion 51, and connection portion 52, but the same applies to portions not assigned reference numerals.

[0040] FIG. 7 is a diagram illustrating the details of the bent portion 51. Although not shown in FIG. 4, the actual bent portion 51 has a portion (hereinafter referred to as the "middle portion") that extends in a direction intermediate between the A direction and the B direction (the Y direction in FIG. 7) as shown in FIG. 7. This is a configuration for preventing etching liquid from remaining in the bent portion 51 when forming the leads 42x and 42y by etching. This makes it possible to accurately form the shapes of the leads 42x and 42y at the bent portion 51.

[0041] Returning to FIG. 4, the intermediate portion of the bent portion 51 is formed with a length necessary and sufficient to prevent etching solution from remaining. Furthermore, the connecting portions 50 and 52 are also formed with a length necessary and sufficient to connect the respective connection destinations (the terminal groups 40a to 40c or the via conductors 35x and 35y) to the lead wires 42x and 42y. Therefore, the lengths of the intermediate portion of the bent portion 51 and the connecting portions 50 and 52 are each sufficiently short compared to the overall length of the lead wires 42x and 42y. In other words, the lengths of the intermediate portion of the bent portion 51 and the connecting portions 50 and 52 can be set to short values ​​such that at least 80% or more, and more preferably 90% or more, of each of the plurality of lead wires 42x and 42y extends along either the A direction or the B direction, and are actually set to such short values. Therefore, even if the intermediate portion of the bending portion 51 and the connecting portions 50, 52 extend in the X direction or the Y direction, it can be said that this does not significantly increase the magnetic coupling generated between each of the plurality of lead wires 42x, 42y and each of the plurality of coils 41x, 41y.

[0042] The second feature is that the terminal groups 40a-40c and the via conductors 35x, 35y are arranged so that the region (second region) in the wiring layer L1 where the plurality of lead wires 42x extend does not intersect with the region (first region) in the wiring layer L1 where the plurality of lead wires 42y extend. This makes it possible to wire the plurality of lead wires 42x, 42y in only one layer, as shown in FIG. 4, and as a result, it is possible to reduce the manufacturing cost of the sensor 13.

[0043] 8 is a diagram showing an area AX in the wiring layer L1 where the plurality of lead wires 42x extend, and an area AY in the wiring layer L1 where the plurality of lead wires 42y extend. As shown in the figure, the area AX is an area including a terminal group 40b-40c connected to a plurality of coils 41x and a plurality of via conductors 35x. The area AY is an area including a terminal group 40a connected to a plurality of coils 41y and a plurality of via conductors 35y. According to the arrangement of the terminal groups 40a-40c and the plurality of via conductors 35x, 35y in this embodiment, the areas AX and AY can be arranged in the wiring layer L1 so as not to intersect with each other. Therefore, the plurality of lead wires 42x, 42y can be wired in only one layer.

[0044] Returning to Figure 4, the third feature is that the arrangement of the terminal groups 40a-40c and the plurality of via conductors 35x, 35y, and the shape of each of the lead wires 42x, 42y are determined so that the absolute value of the moving average deviation rate of the lengths of the lead wires 42x, 42y for each of the coils 41x, 41y is equal to or less than a predetermined value.

[0045] Here, the moving average deviation rate is a value calculated as follows: First, let us assume that the total length of the two leads 42x connected to the k-th coil 41x is L. k When the maximum value of the received strength of the pen signal is detected in the k-th coil 41x, the average length of the lead lines 42x of the group of coils 41x that is referenced to derive the strength distribution of the pen signal is denoted as AVE(k). The average value AVE(k) can be expressed by the following equation (1): where m is the number of coils 41x in the group, and Σ(L k ) is a group of coils 41x each L k is the sum of the above. AVE(k)=(1 / m)×Σ(L k ) ···(1)

[0046] The moving average deviation rate DEV(k) of the lead wire 42x of the coil 41x is expressed by the following equation (2) using this average value AVE(k). DEV(k)=((Lk -AVE(k)) / AVE(k))×100 ···(2)

[0047] Although the coil 41x has been described here, the moving average deviation rate of the length of the lead wire 42y for each coil 41y can be calculated in a similar manner. By arranging the terminal groups 40a-40c and the via conductors 35x, 35y and extending the lead wires 42x, 42y so that the absolute value of the moving average deviation rate calculated in this manner is equal to or less than a predetermined value (at least 30%, preferably 20%), it is possible to prevent large differences in parasitic resistance between the group of coils 41x (or coils 41y) used to derive the intensity distribution of the pen signal. This allows the integrated circuit 20 to correctly derive the position of the stylus 2.

[0048] 9(a) is a diagram plotting, for each coil 41x, the length of the corresponding lead line 42x (the total length of the two corresponding lead lines 42x) and the moving average deviation rate of the lengths of the corresponding lead lines 42x. Also, FIG. 9(b) is a diagram plotting, for each coil 41y, the length of the corresponding lead line 42y (the total length of the two corresponding lead lines 42x) and the moving average deviation rate of the lengths of the corresponding lead line 42y. These diagrams show an example in which the group of coils referenced to derive the pen signal intensity distribution is three coils, including the coil where the maximum value of the received pen signal intensity was detected and the coils on either side of it.

[0049] 9(a) and 9(b), in the sensor 13, the absolute value of the moving average deviation rate of the lengths of the lead wires 42x, 42y for each of the coils 41x, 41y is kept to 20% or less in both the X and Y directions. Therefore, in the tablet terminal 1 according to this embodiment, it can be said that the integrated circuit 20 can correctly derive the position of the stylus 2.

[0050] FIG. 10 is a diagram showing the configuration of wiring included in the wiring layer L1 according to a comparative example. As shown in the figure, the sensor according to this comparative example is configured with multiple coils 100 each extending in the Y direction and multiple via conductors 101 connected to one end or the other of each coil 100. Each coil 100 has a shape similar to that of each coil 41x shown in FIG. 6, except for the positions of both ends. The wiring layer L1 also includes a terminal group 102 including multiple internal terminals corresponding to one end or the other of each coil 100, and multiple lead wires 103 that are provided in a one-to-one correspondence with the ends of each coil 100 and connect the corresponding via conductors 101 to the corresponding internal terminals in the terminal group 102. Note that an actual sensor also includes multiple coils extending in the X direction, as well as corresponding via conductors, terminal groups, and lead wires, but these are not shown in FIG. 10.

[0051] The arrangement of the terminal group 102 is not very flexible due to the constraints imposed by the position of the opening 10a shown in Fig. 1, and the terminal group 102 is arranged near the upper left of the detection area as shown in the figure. As a result, if the via conductors 101 were arranged without particular consideration of the moving average deviation rate described above, there would be places where the positions of the via conductors 101 significantly deviate between two adjacent coils 100, such as between the third and fourth coils 100 from the left in Fig. 10.

[0052] 11 is a diagram plotting, for each coil 100, the length of the corresponding lead line 103 (the total length of the two corresponding lead lines 103) and the moving average deviation rate of the lengths of the corresponding lead lines 103. Also in FIG. 11, an example is shown in which the group of coils 100 referenced to derive the intensity distribution of the pen signal is three coils 100 including the coil 100 where the maximum value of the received strength of the pen signal is detected and the coils on both sides of that coil 100.

[0053] As shown in FIG. 11 , in the sensor according to this comparative example, the absolute values ​​of the moving average deviation rates exceed 30% for the third coil 100 and the fourth coil 100. In particular, the absolute value of the moving average deviation rate for the third coil 100 is a large value exceeding 60%. This results in large differences in parasitic resistance between the group of coils 100 used to derive the intensity distribution of the pen signal, making it impossible for the integrated circuit 20 to correctly derive the position of the stylus 2, at least in the vicinity of the third coil 100 or the fourth coil 100. The sensor 13 according to this embodiment avoids the occurrence of positions where the position of the stylus 2 cannot be correctly derived, and enables the integrated circuit 20 to correctly derive the position of the stylus 2 at any position within the detection area.

[0054] Note that, when the size of the detection area is constant, the difference in length between the lead lines 42x, 42y between adjacent coils 41x, 41y may be used more simply instead of the moving average deviation rate described above. That is, the arrangement of the terminal groups 40a-40c and the plurality of via conductors 35x, 35y, and the shape of each lead line 42x, 42y may be determined so that the absolute value of the difference in length between the lead lines 42x, 42y between adjacent coils 41x, 41y is equal to or less than a predetermined value. This also prevents large differences in parasitic resistance between a group of coils used to derive the intensity distribution of the pen signal, enabling the integrated circuit 20 to accurately derive the position of the stylus 2 at any position within the detection area.

[0055] As described above, according to the sensor 13 of this embodiment, the plurality of lead wires 42x, 42y extend along one or more directions (specifically, the A direction and the B direction) that intersect obliquely with each of the X direction and the Y direction. This makes it possible to reduce magnetic coupling that occurs between the plurality of lead wires 42x, 42y and the plurality of coils 41x, 41y without forming the coils 41x, 41y at an angle.

[0056] Furthermore, according to the sensor 13 of this embodiment, the region AX in which the plurality of lead wires 42x extend does not intersect with the region AY in which the plurality of lead wires 42y extend, so that the plurality of lead wires 42x, 42y that intersect obliquely with the plurality of coils 41x, 41y can be wired in only one layer, the wiring layer L1.

[0057] Furthermore, according to the sensor 13 of this embodiment, it is possible to avoid large differences in parasitic resistance between two adjacent coils 41x and between two adjacent coils 41y, so that the integrated circuit 20 can correctly derive the position of the stylus 2 at any position within the detection area.

[0058] Although the preferred embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and it goes without saying that the present invention can be embodied in various forms without departing from the spirit of the present invention.

[0059] For example, FIG. 12 is a diagram showing the configuration of wiring included in the wiring layer L1 of the sensor 13 according to a modification of the present embodiment. As shown in the figure, in this modification, a plurality of via conductors 35x connected to one end of each of a plurality of coils 41x are commonly connected by a common connection line 45x, and the common connection line 45x is connected to the terminal group 40c by only one lead wire 42x. Similarly, a plurality of via conductors 35y connected to one end of each of a plurality of coils 41y are commonly connected by a common connection line 45y, and the common connection line 45y is connected to the terminal group 40c by only one lead wire 42y. Since it is sufficient to supply a ground potential to one end of each of the plurality of coils 41x and one end of each of the plurality of coils 41y, the integrated circuit 20 can still properly receive pen signals. Note that a ground potential may also be supplied to the other end of each of the plurality of coils 41x and the other end of each of the plurality of coils 41y. In this case, the other ends of the coils 41x and 41y may be connected by a common connection line.

[0060] In this modification, it is preferable that the common connection lines 45x, 45y extend along either direction A or direction B, with some exceptions. The exceptions are the bent portions and the connection portions with the via conductors 35x, 35y, similar to the leads 42x, 42y. This makes it possible to reduce magnetic coupling between the common connection lines 45x, 45y and each of the plurality of coils 41x, 41y. [Example]

[0061] First to fifth examples of the sensor 13 according to this embodiment will be described below.

[0062] FIG. 13 is a diagram showing the configuration of wiring included in the wiring layer L1 of the sensor 13 according to the first embodiment. As can be seen by comparing FIG. 13 with FIG. 4, the arrangement of the terminal groups 40a-40c and via conductors 35x, 35y and the shapes of the lead wires 42x, 42y according to this embodiment are substantially the same as those shown in FIG. 4. On the other hand, although not shown in FIG. 13, the number of turns of the coils 41x, 41y in this embodiment is six, which results in a larger number of via conductors arranged at the edge of the detection area than in FIG. 4. This number of turns is also the same in FIGS. 14 to 17, which will be described later.

[0063] 14 is a diagram showing the configuration of wiring included in the wiring layer L1 of the sensor 13 according to the second embodiment. In this embodiment, a via conductor 35x is arranged along one side of the detection area that forms the end in the Y direction, and a via conductor 35y is arranged along one side of the detection area that forms the end in the X direction. Furthermore, all of the multiple internal terminals connected to both ends of each of the multiple lead lines 42x, 42y are arranged in a straight line to form one terminal group 40a.

[0064] 15 is a diagram showing the configuration of wiring included in the wiring layer L1 of the sensor 13 according to the third embodiment. In this embodiment, via conductors 35x are arranged along one side of the detection area that forms the end in the Y direction, and via conductors 35y are arranged along one side of the detection area that forms the end in the X direction. However, the positions of the plurality of via conductors 35x, 35y are slightly closer to the center of the detection area than in the second embodiment. Furthermore, a plurality of internal terminals connected to both ends of all of the plurality of lead wires 42x and some of the plurality of lead wires 42y form one terminal group 40b, and a plurality of internal terminals connected to both ends of the remaining portions of the plurality of lead wires 42y form one terminal group 40a.

[0065] Fig. 16 is a diagram showing the configuration of wiring included in the wiring layer L1 of the sensor 13 according to the fourth embodiment. As can be seen by comparing Fig. 16 with Fig. 15, this embodiment is similar to the third embodiment except that all of the internal terminals connected to both ends of each of the plurality of lead wires 42x, 42y are arranged in a straight line to form one terminal group 40a, and that the shapes of each of the plurality of lead wires 42x, 42y are slightly different.

[0066] In all of the first to fourth examples, each of the plurality of lead wires 42x, 42y extends along either the A direction or the B direction, except for the connection portions with the terminal group, the bent portions, and the connection portions with the via conductors 35x, 35y. The terminal group and the plurality of via conductors 35x, 35y are arranged so that the region in the wiring layer L1 in which the plurality of lead wires 42x extend does not intersect with the region in the wiring layer L1 in which the plurality of lead wires 42y extend. Furthermore, the arrangement of the terminal group and the plurality of via conductors 35x, 35y and the shape of each lead wire 42x, 42y are determined so that the absolute value of the moving average deviation rate of the lengths of the lead wires 42x, 42y for each coil 41x, 41y is equal to or less than a predetermined value. Therefore, the sensor 13 according to the first to fourth examples achieves the same effects as the sensor 13 according to the present embodiment described above.

[0067] FIG. 17 is a diagram showing the configuration of wiring included in the wiring layer L1 of the sensor 13 according to the fifth embodiment. This embodiment is similar to the second embodiment in that all of the internal terminals connected to both ends of each of the plurality of lead wires 42x, 42y are arranged in a straight line to form one terminal group 40a. However, the arrangement of the via conductors 35x, 35y is significantly different from this embodiment and the other embodiments. In particular, some of the plurality of via conductors 35x are located on the opposite side of the terminal group 40a from the remaining via conductors.

[0068] In this embodiment, each of the plurality of lead wires 42x, 42y has a portion extending along either the A direction or the B direction. Therefore, compared to the example shown in FIG. 10 , it can be said that the magnetic coupling occurring between each of the plurality of lead wires 42x, 42y and each of the plurality of coils 41x, 41y can be reduced. Furthermore, the terminal group 40a and each of the plurality of via conductors 35x, 35y are arranged so that the region in the wiring layer L1 where the plurality of lead wires 42x extend does not intersect with the region in the wiring layer L1 where the plurality of lead wires 42y extend. Therefore, each of the plurality of lead wires 42x, 42y, which obliquely intersects with each of the plurality of coils 41x, 41y, can be wired in only one layer, the wiring layer L1. [Explanation of symbols]

[0069] 1 tablet device 2 stylus 10 Display module rear cover 10a opening 11 Shield plate 12 spacers 13 Sensors 16 Display panel 17 Display module frame 18 Glass 20 Integrated Circuits 21 Bent PCB 30,31 Insulating layer 35, 35x, 35y via conductor 40a~40c terminal group 41x, 41y coil 42x, 42y leader line 45x, 45y common connection line 50,52 Connection 51 Bend L1~L3 wiring layer

Claims

1. a plurality of coils including a plurality of first coils each extending in a first direction parallel to one side of a rectangular detection area, and a plurality of second coils each extending in a second direction orthogonal to the first direction; a plurality of terminals provided corresponding to one end and the other end of each of the plurality of coils; a plurality of lead wires connecting the plurality of terminals to one end or the other end of the corresponding plurality of coils, each of the plurality of lead wires is formed in a wiring layer different from that of the plurality of first coils and the plurality of second coils, and is thereby extended into the detection area; and the lead wires extend linearly along one or more directions obliquely intersecting with each of the first and second directions, except for connection portions with the plurality of terminals, connection portions with one end or the other end of the plurality of coils, and bent portions; Sensor.

2. the plurality of lead wires extend along any one of the one or more directions, except for connection portions with the corresponding terminals, bent portions, and connection portions with the corresponding coils; The sensor of claim 1 .

3. At least 80% or more of each of the plurality of lead lines extends along one of the one or more directions.

3. The sensor according to claim 1 or 2.

4. the one or more directions include a third direction that forms a 45-degree angle with the first direction, and a fourth direction that is perpendicular to the third direction; 4. The sensor according to claim 2, wherein the sensor is a casing.

5. the plurality of lead lines are wirings formed in a first wiring layer, the plurality of lead wires include a plurality of first lead wires connected to one ends or the other ends of the plurality of first coils, and a plurality of second lead wires connected to one ends or the other ends of the plurality of second coils, each of the plurality of first lead lines is electrically connected to one end or the other end of a corresponding one of the plurality of first coils at a first connection point provided in the first wiring layer; each of the plurality of second lead lines is electrically connected to one end or the other end of a corresponding one of the plurality of second coils at a second connection point provided in the first wiring layer; the plurality of terminals, the plurality of first connection points, and the plurality of second connection points are arranged so that a first region in which the plurality of first lead lines extend does not intersect with a second region in which the plurality of second lead lines extend; A sensor according to any one of claims 1 to 4.

6. the first region includes a plurality of terminals connected to the plurality of first coils among the plurality of terminals and the plurality of first connection points; the second region includes a plurality of terminals connected to the plurality of second coils among the plurality of terminals, and the plurality of second connection points; The sensor of claim 5.

7. a second wiring layer on which the plurality of first coils extend; a third wiring layer on which the plurality of second coils extend; a plurality of first via conductors connected to one end or the other end of each of the plurality of first coils; a plurality of second via conductors connected to one end or the other end of each of the plurality of second coils; the plurality of first connection points are connection points between the plurality of first via conductors and the first wiring layer, the plurality of second connection points are connection points between the plurality of second via conductors and the first wiring layer; 7. The sensor according to claim 5 or 6.

8. the arrangement of the plurality of terminals, the arrangement of the connection points of the plurality of lead wires and the plurality of coils, and the shape of each of the plurality of lead wires are determined so that the absolute value of the moving average deviation rate of the lead wire for each of the coils is equal to or less than a predetermined value; A sensor according to any one of claims 1 to 4.

9. The predetermined value is 20%. The sensor of claim 8.

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