WO2013147456A1

WO2013147456A1 - Tablet having improved power coil structure

Info

Publication number: WO2013147456A1
Application number: PCT/KR2013/002334
Authority: WO
Inventors: 유영기
Original assignee: 주식회사 윈터치
Priority date: 2012-03-26
Filing date: 2013-03-21
Publication date: 2013-10-03
Also published as: KR20130108929A; KR101355940B1

Abstract

The present invention relates to a tablet having an improved power coil structure, the tablet comprising: an electronic pen having a resonance circuit for storing induction energy when external induction electromagnetic force is applied and emits self-induction electromagnetic force through the stored induction energy when the external induction electromagnetic force is not applied; a power supply driver and a power coil, formed to surround an electronic pen sensing area, for emitting the external induction electromagnetic force; and a plurality of line antennas, line selection circuits, and coordinate sensing circuits, for sensing the position of the electromagnetic pen, wherein the power coil is formed in such a manner that a strip-shaped insulating film, in which multiple line patterns are formed to be parallel to each other at the same intervals, is bent and rolled so as to connect one end portion and the other end portion of the film to each other, and wherein the connection is misaligned such that the end portions of the line patterns formed on the one end portion of the film are connected to the end portions of the same and neighboring line patterns among the end portions of the line patterns formed on the other end portion of the film.

Description

Tablet with improved power coil structure

TECHNICAL FIELD The present invention relates to a tablet having an improved power coil structure, and more particularly, to a tablet that efficiently improves an arrangement of power coils surrounding an electronic pen sensing region.

The touch screen includes a display panel, such as an LCD or LED panel, and a tablet disposed on the front surface (front facing surface on which an image is displayed) or the back of the display panel to detect the approach or touch of an electronic pen operated by a user. It is made to include.

The operation principle and configuration of the tablet may be understood with reference to the contents of Korean Patent No. 10-910348 (name of the invention: coordinate input device), which is a conventional technology for implementing a touch screen, and a detailed description thereof will be omitted.

On the other hand, in the above prior art, a power coil, a line antenna, and a loop antenna are arranged to have a positional relationship as shown in FIG.

In the drawing, a loop antenna constituting the electronic pen detection region, a plurality of horizontal line antennas and vertical line antennas connected in a comb-tooth form to the loop antenna, and a power coil disposed in a form surrounding the loop antenna You can see the form.

As such, the power coil is formed outside the electronic pen sensing region. In addition, in order for the power coil to transmit more induced electromagnetic force to the electronic pen in a shorter time, the number of turns of the coil must be increased, so that the area occupied by the power coil becomes larger, thereby relatively detecting the electronic pen. The area can be reduced.

In display devices of mobile devices such as mobile phones, tablet PCs, and laptop computers, the bezel is minimized so that the area where the image is displayed is the entire surface of the display device, and the electronic pen detects the entire area where the image is displayed. Since it is necessary to configure the area, if the power coil is constructed in a planar manner as in the related art, it does not meet the recent trend of requiring a minimized bezel.

As described above, the present invention intends to minimize the area of the power coil among the elements constituting the tablet, thereby maximizing the electronic pen sensing area and minimizing the bezel area surrounding the electronic pen sensing area. .

The present invention for providing a tablet having an improved power coil structure in order to achieve the above object, has a resonant circuit to store the induced energy when the external induction electromagnetic force is applied, the external induction electromagnetic force is not applied The electronic pen is configured to surround the electronic pen which emits its own induced electromagnetic force by the induced and stored energy, a power supply driver that outputs AC power of a predetermined frequency, and an electronic pen sensing region capable of sensing the position of the electronic pen. A plurality of power coils that emit the external induced electromagnetic force by the AC power output from the power supply driver, and a plurality of first ends connected to each other in a comb shape parallel to each other to form the electronic pen sensing region on an insulating substrate, and the other ends separated from each other. A line antenna and one of the plurality of line antennas A line selection circuit connecting the outer line antennas to each other to form a loop structure and connecting them to ground, and selecting the other end of the plurality of line antennas in an insulated state from the loop structure and setting them as differential outputs; Controlling the operation of the power supply driver and controlling the selection operation of the line selection circuit, by using the induced current appearing at the differential output by self-induced electromagnetic force emitted from the electronic pen And a coordinate sensing circuit for determining the position of the electronic pen, wherein the power coil bends a band-shaped insulating film having a plurality of line patterns parallel to each other at equal intervals, thereby connecting one end and the other end of the film to each other. However, the ends of the line pattern formed at one end of the film is It is characterized in that it is formed by alternately connecting so as to be connected to the end of the line pattern adjacent to itself of the end of the line pattern formed on the other end of the film.

In addition, the plurality of line patterns are formed by printing a conductive material on the surface of the film.

In addition, an end portion (first surface end portion pattern) of the line pattern formed on the first surface of one end portion of the film passes through the film and is exposed to the second surface side of the film, and when the film is bent, the film A part of one end of the line overlapping with a part of the other end of the film, and an end of the line pattern formed on the first surface of the first surface exposed to the second surface and the first surface of the other end of the film Connect the other end pattern on one side).

In addition, the line pattern is formed on the second surface of the film, and the other end of the line pattern (second surface other end pattern) formed on the second surface of the other end of the film penetrates the film to make One end of the line pattern formed on the second surface of the other end portion exposed to the first surface and the second surface of the one end portion of the film when the film is bent and exposed to one surface side (second surface one end pattern) ) By connecting each other, the power coil is formed by connecting both the line pattern formed on the first surface of the film and the line pattern formed on the second surface of the film.

In addition, another aspect of the present invention for providing a tablet having an improved power coil structure in order to achieve the above object, has a resonant circuit to store the induced energy when an external inductive electromagnetic force is applied, When the induced electromagnetic force is not applied, the electronic pen which emits its own induced electromagnetic force by induced and stored energy, a power supply driver for outputting AC power of a predetermined frequency, and an electronic pen detection area capable of sensing the position of the electronic pen. It is formed so as to surround the power coil for emitting the external induced electromagnetic force by the alternating current power output from the power supply driver, and one end is connected to each other and the other end in a comb shape parallel to each other to form the electronic pen detection region on an insulating film Is a plurality of line antennas separated from each other, A line which connects the outermost line antennas among the line antennas to ground to form a loop structure, and selects the other end of the plurality of line antennas to be insulated from the loop structure and set them as differential outputs. The selected line antenna by controlling a selection circuit and an operation of the power supply driver and controlling a selection operation of the line selection circuit to utilize an induced current appearing at the differential output by a self-inducing electromagnetic force emitted from the electronic pen. And a coordinate sensing circuit configured to determine a position of the electronic pen based on the above, wherein the film includes a rectangular bottom plate forming the electronic pen sensing region and at least one side of a rectangular shape of the bottom plate. An extension extended by a width, wherein the power coil is conductive A line pattern flows in the extension part of the film along the length direction of the extension part, and then at the end of the extension part, enters and flows back into the adjacent extension part via the bottom plate, along the circumference of the bottom plate. Characterized in that the power coil is formed.

In addition, the extension portion is folded up from the bottom plate to form a side wall surrounding the bottom plate.

In addition, the other ends of the plurality of line antennas of the film are connected to the line selection circuit through a pattern connection part formed on one surface of one side of the bottom plate where the extension part is not formed, and the line pattern of the power coil is the pattern One side of the bottom plate formed with a connection portion is formed to flow to the opposite side of the one surface.

In addition, the pattern of the power coil is formed on both sides of the film in a portion except for the pattern connecting portion.

According to the present invention made up of the above-described configuration, the tablet manufacturing process can be simplified by mounting the power coil essential to the tablet in a separate component and combining it with the power supply driver of the tablet.

In addition, even if the bezel width of the display device is minimized in the mobile device in which the tablet is mounted, the power coil may be efficiently mounted.

1 is a view showing the positional relationship between a power coil, a line antenna and a loop antenna in a conventional tablet.

2 is a view for explaining a schematic structure of a tablet for detecting the structure of the electronic pen and the position of the electronic pen according to the present invention.

3 is a view schematically showing the configuration and structure of a mobile device with a tablet according to the present invention.

4 is a diagram illustrating an example of a method of configuring a power coil.

It is a figure for demonstrating the form and coupling method which formed the power coil by the conductive line pattern of the power coil in one side of the strip | belt-shaped flexible film.

6 is a cross-sectional view showing the formation of the conductive line pattern 30P on both sides of the strip-shaped film 30B.

FIG. 7 is a view for explaining various methods of connecting the respective line patterns of both ends of the film when the power coil is formed by bending the film having the line patterns formed on both sides thereof.

FIG. 8: is a figure explaining the form of the edge part of each line pattern, when some of the edge parts of the film in which the line pattern was formed in both surfaces overlapping and bonding together.

FIG. 9 is a view for explaining another method of making a power coil by bending a strip of film. FIG.

FIG. 10 is a block diagram illustrating a configuration of a mobile device in an embodiment in which the power coil is separately configured from the mobile device.

11 is a diagram illustrating a method of mounting a power coil to a mobile device.

12 is a diagram for explaining a power coil configuration method in which a power coil is formed on a substrate integrated with a line antenna and a loop antenna.

FIG. 13 is an enlarged view of a portion of the power coil pattern shown in FIG. 12 via the bottom plate at the end of the extension portion.

FIG. 14 is a view illustrating a pattern connection part in which a pattern of a power coil, a line antenna, and a loop antenna flows out from the bottom to the outside.

FIG. 15 is a view showing an integrated configuration of a film having a power coil according to the present invention with a display device.

Hereinafter, the structure and operation of the tablet according to the present invention, and various arrangement structures of the power coil will be described.

First, referring to FIG. 2, the schematic structure of the tablet for detecting the structure of the electronic pen and the position of the electronic pen will be described. First, referring to FIG. 2 (a), a plurality of X-axis line antennas 20X arranged in a longitudinal direction (Y-axis direction) and arranged in parallel in a horizontal direction (X-axis direction) and in the X-axis direction It can be seen that the structure of the Y-axis line antennas 20Y which are arranged long and arranged in parallel in the Y-axis direction (in this case, each of the X-axis line antennas and the Y-axis line antennas is connected to the loop antenna). Except in other parts). The X-axis position and Y-axis position of the electronic pen can be detected by the X-axis line antennas 20X and Y-axis line antennas 20Y, respectively, and as a result, two-dimensional coordinates of the electronic pen can be calculated. Will be.

At this time, the area (the area indicated by the dotted line) where the X-axis line antennas 20X and the Y-axis line antennas 20Y are formed becomes an electronic pen detection area A in which the position of the electronic pen P can be detected. .

The power coil 30 is disposed outside the electronic pen detecting region A (outside of the electronic pen detecting region) to surround the X axis line antennas 20X and the Y axis line antennas 20Y. . The power coil 30 induces an electromagnetic force to supply energy to the electronic pen.

One ends of the X-axis line antennas 20Y are connected to the loop antenna 10 and the other ends are connected as inputs to the multiplexer 15. The output of the multiplexer 15 is connected to one input of the amplifier 17.

In addition, one ends of the Y-axis line antennas 20Y are also connected to the loop antenna 10, the other ends are connected to the input of the multiplexer 25, and the output of the multiplexer 25 is an input of the amplifier 17. .

The multiplexers 12 and 25 constitute a first line select circuit and a second line select circuit, respectively.

Here, the loop antenna to which the X-axis line antennas are connected and the loop antenna 10 to which the Y-axis line antennas are connected may share a single loop antenna as shown in the drawing, but are independently configured for each line antenna. May be

The amplifier 17 inputs the potential of either the outputs of the

multiplexers

15 and 25 and the loop antenna (the loop antenna is kept at the same potential), and outputs the potential difference between them. The output potential difference is input to the MCU 18.

The MCU 18 sends a selection signal to the

multiplexers

15 and 25 to select the other end of either line antenna (one of the X-axis line antennas and the Y-axis line antennas), thereby providing a voltage from the selected other end. This is input to the amplifier 17. And change the selection signal to continue to output to the

multiplexers

15 and 25 so as to scan for other line antennas, and receive and select the potential differences output from the amplifier 17 each time one line antenna is selected. The positional relationship of the electronic pen P with respect to the line antenna is detected. When all or part of the line antennas are scanned, the coordinates of the electronic pen P are calculated using the detected positional relationships.

In addition, the MCU 18 may control the operation of the power supply driver 32 by generating a control signal corresponding to the resonance frequency of the electronic pen, thereby controlling the supply of energy to the electronic pen.

Here, the electronic pen detecting region A in which the antenna patterns for detecting the position of the electronic pen and the power coil are formed may include a driving circuit region including the

multiplexers

15 and 25, the amplifier 17, and the MCU 18. Separated from, it may be formed on an independent substrate (see dashed line in the drawing).

Next, Figure 2 (b) shows a schematic configuration of the electronic pen. The electronic pen P has a resonant circuit including at least an inductor L and a capacitor C, and is caused by an induced current generated in the inductor L when the resonant circuit is located in an electromagnetic field in which electromagnetic force is applied. The capacitor C causes resonance while charging and discharging. This resonance phenomenon persists for a predetermined time according to the time constant of the resonance circuit even after the electromagnetic force emitted from the power coil is removed.

In addition, the electronic pen may be provided with circuit elements that operate using the generated induced current. These circuit elements allow digital communication between the electronic pen and the MCU 18 of the tablet by generating on / off of the electromagnetic force emitted from the electronic pen or variation of the resonant frequency.

3 is a view schematically showing the configuration and structure of a mobile device with a tablet having an improved power coil structure according to the invention as described above. The mobile device 110 includes a tablet module and a mobile function module.

The tablet module operates on the same principle as described above, which includes a power supply driver 32, a power coil 30, a loop antenna 10 and a line antenna 20,

line selection circuits

15 and 25, and coordinate sensing. Circuit 18.

The mobile function module provides a display function section 41, a communication function section 42, and an operation function section 43, thereby providing a portable multimedia playback function, a wired / wireless communication function as a mobile phone, and various inputs and modifications of other user operations. This can be done.

4 is a view showing an example of a method of manufacturing a power coil applied to a tablet according to an embodiment of the present invention. First, the conductive line pattern 30P for constituting the power coil 30 is printed on the strip-shaped flexible film 30B by screen printing or the like. The pattern 30P of the power coil is formed in plural in parallel at equal intervals with both ends open at the ends of the flexible film 30B (Fig. 4 (a)).

When the band-shaped flexible film 30B is bent and rolled so as to be shifted so that each pattern at both ends is connected to an adjacent pattern, each line pattern 30P forms a coil shape. In this way, the power coil 30 can be simply formed (Fig. 4 (b)).

In this way, the band-shaped flexible film 30B is attached to the wall inside the main body of the mobile device 110 so as to surround the electronic pen detecting region A by the line antenna 20 and the loop antenna 10, thereby completing the mounting. do. Both ends of the power coil pattern 30P formed in the flexible film 30B may be connected to the power supply driver 32 by a conductive wire W or another type of circuit pattern (FIG. 4C).

5 is a figure for demonstrating the form and coupling method which formed the power coil by the conductive line pattern of the power coil in one surface of the strip | belt-shaped flexible film.

As a method of bending the film to connect the line pattern 30P formed on one surface of the flexible film 30B to each other by rolling the film, there may be a method of butting both ends, as shown in FIG. Since the process of connecting the two to each other can be complicated and difficult, as shown in Fig. 5 (a) by overlapping a portion of the end of the film 30B with each other, it is possible to electrically connect each line pattern (30P) by a simple bonding. .

That is, as shown in Fig. 5 (b), when the line pattern 30P on one side is penetrated through the film 30B and exposed to the other side, the both ends of the film 30B are simply overlapped and bonded. It is possible to form a coil structure.

On the other hand, in the improved power coil structure according to the present invention, line patterns 30P may be formed on both sides of the flexible film 30B, respectively. 6 is a cross-sectional view showing the formation of the conductive line pattern 30P on both sides of the strip-shaped film 30B. In the figure, although the patterns on both sides are configured to be symmetrical with each other, it is also possible to configure them alternately.

As such, the conductive line patterns 30P are formed on both sides of the film 30B, and the patterns 30P are connected to each other while the film 30B is bent, thereby making the number of turns of the power coil 30 two. You can increase it twice.

FIG. 7 is a view for explaining various methods of connecting the respective line patterns of both ends of the film when the power coil is formed by bending the film having the line patterns formed on both sides thereof. FIG. 7A is a diagram for explaining a configuration in which the line pattern on the first surface and the line pattern on the second surface are alternately connected, and the number of times the connection of the patterns crosses other patterns is minimized.

In FIG. 7B, only the line patterns of the first surface are first connected to each other to form a coil, and then the line patterns of the second surface are connected to each other to form a coil. At this time, in forming the coil, the direction in which the end portions of the line patterns on the first surface are staggered from each other and the direction in which the end portions of the line patterns on the second surface are staggered from each other are characterized by being opposite to each other.

In Fig. 7 (c), only the line patterns of the first surface are connected to each other first to construct a coil, and then the line patterns of the second surface are connected to each other to form a coil, so that the ends of the patterns are the same in the opposite directions. Configured. In this configuration, at least one pattern of connecting structures completely intersects with other connecting structures in an insulated state.

Of course, various methods may be applied without being limited to such a connection structure.

In the case where the line pattern 30P is formed on both sides of the film 30B at the same time, as shown in the figure, either end of the film 30B is reduced by either reducing the line width of the pattern or by using a space in which no line pattern is formed. A part of the line pattern 30P of the surface is configured to be exposed to the other side.

In the drawing, when the end (first surface one end pattern) of the line pattern formed on the first surface of one end of the film 30B is exposed through the film to the second surface side of the film 30B, and the film is bent, One end pattern of the first surface exposed to the second surface and an end (first surface other end pattern) of the line pattern formed on the first surface of the other end of the film 30B are connected to each other.

Further, when the other end of the line pattern (second surface other end pattern) formed on the second surface of the other end of the film 30B is exposed to the first surface side through the film 30B, and the film is bent, The second surface other end pattern exposed on the surface and the end (second surface one end pattern) of the line pattern formed on the second surface of one end of the film 30B are connected to each other.

Thereby, the power coil which connected both the line pattern formed in the 1st surface of a film, and the line pattern formed in the 2nd surface of a film is comprised.

FIG. 9 is a view for explaining another method of making a power coil by bending a strip of film. FIG. In FIGS. 4-8, the method of constructing a power coil by directly bonding both ends of the strip | belt-shaped film was demonstrated. However, in such a configuration, in order to connect both ends of the line pattern constituting the power coil to the power supply driver, wire bonding or another line pattern had to be connected separately. However, as shown in (b) and (d) of FIG. 9, if a protruding portion is formed in the strip-shaped film in which the power coil pattern is formed, and the connection of the line pattern is implemented through the protruding portions, ) And (c), the connection between the power coil and the power supply driver can be easily realized.

In the drawings, the shape of the line pattern formed on the film including the protruding portion is shown as an example.

Next, referring to FIGS. 10 and 11, a method of mounting the power coil as shown in FIGS. 4 through 12 to the mobile device will be described. Since the power coil 30 in the power coil structure as shown in FIGS. 4 to 12 may be implemented using a film 30B separate from the line antenna 20 and the loop antenna 10, It may be mounted at a free position inside the mobile device 110. That is, the film 30B may be attached to the inside or the outside of the side wall constituting the main body of the mobile device 110.

In addition, as another mounting example, the power coil may be mounted inside or outside the carrying case 120 separately attached to the outside of the mobile device 110 (see FIG. 11).

FIG. 10 is a block diagram illustrating a configuration of a mobile device in an embodiment in which the power coil is separately configured from the mobile device. Referring to the drawings, the power coil 30 is formed inside the case 120 separate from the mobile device 110, and the power coil 30 formed in the case 120 is a power supply driver configured in the mobile device 110. And a first connector 33 and a second connector 34 (see Fig. 11).

The first connector 33 and the second connector 34 may be contacts of a conductive material exposed to the outside, and when the mobile device 110 and the case 120 are coupled to each other, the first connector 33 and the second connector 34 are configured to be in contact with each other. desirable.

Thus, when the mobile device 110 and the case 120 are coupled to each other, pulsating AC power output from the power supply driver 32 of the tablet module can be delivered to the power coil 30, and the electronic pen ( Coordinate input using P) becomes possible.

According to this structure, the power coil 30 can be selectively applied and driven. In addition, since the electronic pen has a built-in power supply, it is possible to select whether to use the power coil in response to the case where power supply by the power coil is unnecessary.

Next, another form of the power coil structure in the tablet according to the present invention will be described.

FIG. 12 is a view for explaining a power coil configuration method that allows a tablet to be more easily formed by configuring a line antenna, a loop antenna, and a power coil on an integrated substrate while minimizing the bezel area in which the power coil is disposed.

12 (a) is a diagram illustrating a shape of a substrate on which a power coil, a line antenna, and a loop antenna are to be formed. Referring to the drawings, it can be seen that at least one rectangular bottom plate B and an extended portion E having a form in which at least one side of the bottom plate B is extended by a predetermined width are configured. At this time, each expansion portion (E) is configured to be folded up from the bottom plate (B), the substrate is preferably a film of a flexible material.

In addition, since the line antenna 20 and the loop antenna 10 should be formed on the substrate (film), it is preferable that the substrate (film) is made of a transparent material.

FIG. 12 (b) shows that a pattern of a line antenna, a loop antenna, and a power coil is formed by printing a conductive pattern on the film shown in FIG. 12 (a) by screen printing or the like.

At this time, the power coil 30 flows along the longitudinal direction of the expansion portion E inside the expansion portion E of the film, and then extends adjacent again via the bottom plate B at the end portion of the expansion portion E. It is comprised so that it may enter and flow into the part E, and the coil structure is formed along the periphery of the bottom plate B. FIG.

On the other hand, in order to form the electronic pen detection area A, the loop antenna 10 and the line antenna 20 are formed in the bottom plate B. FIG.

In addition, a pattern connecting portion 37 for drawing the other ends of the plurality of line antennas to the outside is formed on one surface of the film. This pattern connecting portion 37 is preferably formed in a portion where an extension is not formed (the film is not folded up).

At this time, the pattern of the power coil 30 does not intersect with the pattern of the line antenna 20 and the loop antenna 10 flowing out of the pattern connecting portion 37 (to cross in an insulated state), the bottom plate (B) ) Is preferably formed on the surface opposite to the surface on which the pattern connecting portion 37 is formed. That is, in the rightmost side of the bottom plate B in the figure, for example, the other ends of the line antenna and the pattern of the loop antenna are configured to flow along the upper surface of the bottom plate B, and the pattern of the power coil The silver may be configured to flow along the rear surface of the bottom plate (B).

On the other hand, in the pattern of the power coil 30, the part via the bottom plate B at the edge part of the expansion part E was expanded and shown in FIG. In this part, it is preferable that a part of the loop antenna 10 is bent inward so as not to cross the pattern of the power coil 30.

FIG. 14 is a diagram illustrating a pattern connection portion of the power coil, the line antenna, and the loop antenna flowing out from the bottom to be connected to the power supply driver and the multiplexer, respectively. The pattern of the line antenna 20 and the ground connection pattern of the loop antenna 10 flow out to the first surface of the pattern connection part 37, and the power coil 30 is configured to the second surface of the pattern connection part 37. Line patterns flow along the circumference of the bottom plate and both ends of the coil structure flow out toward the power supply driver 32.

The pattern connecting portion 37 is coupled to an external connection connector (not shown) or the like.

FIG. 15 is a diagram illustrating an integrated configuration of a film having a power coil configured as shown in FIGS. 12 to 14 with a display device. According to the power coil configuration in which the side wall is formed by using the expansion unit E as described above, even if the display device 41 has almost no bezel, the power coil 30 can be mounted on the side of the display device 41. Can be.

As a result, the entire surface of the display device 41 may be implemented as the electronic pen sensing region A, and there is no need to configure a separate thick bezel to form the power coil 30. As a result, the bezel surrounding the display device 41 may be minimized in the mobile device 110.

In addition, since the conductive line pattern can be formed at the same time as the printing of the line antenna 20 and the loop antenna 10 and the power coil 30 can be configured, the manufacturing process is simple and the manufacturing cost can be reduced.

Claims

An electronic pen having a resonant circuit for storing induced energy when an external induced electromagnetic force is applied, and releasing its induced electromagnetic force by induced and stored energy when the external induced electromagnetic force is not applied;

A power supply driver for outputting AC power of a predetermined frequency;

A power coil formed to surround an electronic pen sensing region capable of sensing a position of the electronic pen, and emitting the external induced electromagnetic force by AC power output from the power supply driver;

A plurality of line antennas having one end connected to each other and the other ends separated from each other in a comb shape parallel to each other to form the electronic pen sensing region on an insulating substrate;

The outermost line antennas of the plurality of line antennas are electrically connected to each other to form a loop structure, and connected to ground, and the other end of the plurality of line antennas is selected to be insulated from the loop structure and differentially connected. A line selection circuit to be set as an output,

Controlling the operation of the power supply driver and controlling the selection operation of the line selection circuit, by using the induced current appearing at the differential output by self-induced electromagnetic force emitted from the electronic pen A coordinate sensing circuit for determining the position of the electronic pen,

The power coil is formed by bending a band-shaped insulating film having a plurality of line patterns parallel to each other at equal intervals to connect one end and the other end of the film to each other, and ends of the line pattern formed at one end of the film. A tablet having an improved power coil structure, characterized in that it is formed by alternately connecting so as to be connected to an end of a line pattern adjacent to itself among the ends of the line pattern formed at the other end of the film.
The method of claim 1,

And the plurality of line patterns is formed by printing a conductive material on the surface of the film.
The method of claim 1,

An end portion (first surface end portion pattern) of the line pattern formed on the first surface of one end portion of the film passes through the film and is exposed to the second surface side of the film,

When the film is bent, a part of one end of the film is overlapped with a part of the other end of the film to expose the first surface one end pattern exposed to the second surface and the first surface of the other end of the film. A tablet having an improved power coil structure, characterized in that the ends (the other end surface of the first surface) of the line pattern formed in the interconnection are connected to each other.
The method of claim 3,

The line pattern is also formed on the second surface of the film,

The other end of the line pattern (second surface other end pattern) formed on the second surface of the other end of the film passes through the film and is exposed to the first surface side of the film,

When the film is bent, by connecting the second surface other end pattern exposed on the first surface and the end (second surface one end pattern) of the line pattern formed on the second surface of one end of the film to each other,

And the power coil is formed by connecting both the line pattern formed on the first side of the film and the line pattern formed on the second side of the film.
An electronic pen having a resonant circuit for storing induced energy when an external induced electromagnetic force is applied, and releasing its induced electromagnetic force by induced and stored energy when the external induced electromagnetic force is not applied;

A power supply driver for outputting AC power of a predetermined frequency;

A power coil formed to surround an electronic pen sensing region capable of sensing a position of the electronic pen, and emitting the external induced electromagnetic force by AC power output from the power supply driver;

A plurality of line antennas having one end connected to each other and the other ends separated from each other in a comb-like shape parallel to each other to form the electronic pen sensing region on an insulating film;

The outermost line antennas of the plurality of line antennas are connected to each other to form a loop structure, and connected to ground, and the other end of the plurality of line antennas is selected to be insulated from the loop structure to provide a differential output. A line selection circuit to be set,

Controlling the operation of the power supply driver and controlling the selection operation of the line selection circuit, by using the induced current appearing at the differential output by self-induced electromagnetic force emitted from the electronic pen A coordinate sensing circuit for determining the position of the electronic pen,

The film includes a rectangular bottom plate that forms the electronic pen sensing region, and an extension that extends by a predetermined width on at least one side of a rectangular shape of the bottom plate.

The power coil is configured such that a conductive line pattern flows along the lengthwise direction of the extension in the extension of the film and then flows back into the adjacent extension via the bottom plate at the end of the extension. Tablet with improved power coil structure, characterized in that the power coil is formed along the circumference of the bottom plate.
The method of claim 5,

And the expansion portion is folded up from the bottom plate to form a side wall surrounding the bottom plate.
The method of claim 5,

The other ends of the plurality of line antennas of the film are connected to the line selection circuit through a pattern connection part formed on one side of one side of the bottom plate where the extension part is not formed.

The line pattern of the power coil tablet having an improved power coil structure, characterized in that formed on one side of the bottom plate on which the pattern connecting portion is formed to flow to the opposite side of the one surface.
The method of claim 7, wherein

A tablet having an improved power coil structure, characterized in that the pattern of the power coil is formed on both sides of the film in portions other than the pattern connection portion.