Stylus pen

Abstract

To provide a stylus pen for effectively receiving and transmitting magnetic signals that are received from and transmitted to an electronic device.SOLUTION: A stylus pen can include a ferrite core and a coil that includes a plurality of metal wires twisted so that the number of twist turns per unit length becomes n or more and is wound on an exterior surface of the ferrite core.SELECTED DRAWING: Figure 20

Description

Technical Field

[0001] The present disclosure relates to a stylus pen.

Background Art

[0002] Various terminals such as mobile phones, smartphones, tablets, laptop computers, digital broadcast terminals, PDAs (Personal Digital Assistants), PMPs (Portable Multimedia Players), and navigation devices are equipped with touch sensors.

[0003] In such terminals, the touch sensor can be located on a display panel that displays an image or in an area of the terminal body. By the user touching the touch sensor to interact with the terminal, the terminal can provide an intuitive user interface to the user.

[0004] The user can use a stylus pen for precise touch input. Such a stylus pen can transmit and receive signals to and from the touch sensor through electrical and / or magnetic means.

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of one embodiment is to provide a stylus pen for effectively receiving and transmitting magnetic signals received from an electronic device and magnetic signals transmitted to the electronic device.

[0006] An object of one embodiment is to provide a stylus pen that increases the Q value of an inductor.

Means for Solving the Problems

[0007] A stylus pen according to one embodiment for solving the aforementioned technical problems may include a ferrite core and a plurality of metal wires twisted together such that the number of twist turns per unit length is n or more, and may include a coil wound on the outer surface of the ferrite core.

[0008] A touch system according to one embodiment may include a stylus pen including an inductor section comprising a Litz wire cable containing a plurality of metal wires twisted in a rotatable manner on a portion of a ferrite core, a capacitor electrically connected to the inductor section, and a touchscreen including a touch electrode layer that receives electromagnetic signals resonated by the stylus pen.

[0009] One embodiment may include an inductor section containing a coil comprising a plurality of metal wires wound in multiple steps and twisted in a rotating manner around a portion of a ferrite core, and a capacitor section electrically connected to the coil. [Brief explanation of the drawing]

[0010] [Figure 1] This is a conceptual diagram showing a stylus pen and electronic devices. [Figure 2] This diagram schematically illustrates the signal transmission operation between a stylus pen and an electronic device. [Figure 3] This diagram schematically illustrates the signal transmission operation between a stylus pen and an electronic device. [Figure 4] This is a diagram showing a stylus pen. [Figure 5] This is a conceptual diagram specifically illustrating the inductor section of a stylus pen. [Figure 6] This is a conceptual diagram specifically illustrating the inductor section of a stylus pen. [Figure 7] This is a diagram showing the number of twist turns in a coil. [Figure 8] This is a diagram showing the number of twist turns in a coil. [Figure 9] This is a diagram showing the number of twist turns in a coil. [Figure 10] A drawing showing the number of twist turns of a coil. [Figure 11] A cross-sectional view of a coil according to an embodiment. [Figure 12] A cross-sectional view of a coil according to a comparative example. [Figure 13] A graph showing the Q value according to the frequency of an inductor part according to an embodiment. [Figure 14] A drawing showing the inductance, resistance, and Q value of an inductor part including a coil according to a comparative example. [Figure 15] A drawing showing the inductance, resistance, and Q value of an inductor part including a coil according to an embodiment. [Figure 16] A graph showing the Q value of an inductor part according to the number of twist turns of a coil at a frequency of 600 kHz. [Figure 17] A drawing showing a U-type winding method. [Figure 18] A drawing showing a zigzag-type winding method. [Figure 19] A graph showing the Q value of an inductor measured by changing the frequency through an E4980A precision LCR meter of KEYSIGHT TECHNOGIES. [[ID=第31]] [Figure 20] A drawing showing an N-step type winding method. [Figure 21] A conceptual diagram showing an inductor part of a stylus pen using an N-step type winding method. [Figure 22] A cross-sectional view of an inductor part of a stylus pen using an N-step type winding method. [Figure 23] A drawing showing the Q value according to the number of twist turns and the winding method.

Mode for Carrying Out the Invention

[0011] It should be noted that there seems to be a minor error in the original text where "第31" is likely a mislabeled "ID=31". This has been maintained in the translation for consistency with the original.Hereinafter, embodiments of the present invention will be described in detail so that those having ordinary knowledge in the technical field to which the present invention pertains can easily implement it with reference to the attached drawings. However, the present invention can be embodied in various different forms and is not limited to the embodiments described herein.

[0012] In the drawings, in order to clearly explain the present invention, unnecessary parts for the explanation are omitted, and similar parts throughout the specification are given similar reference numerals.

[0013] Also, the sizes and thicknesses of each configuration shown in the drawings are arbitrarily shown for the convenience of explanation, and the present invention is not necessarily limited to what is shown in the drawings. In the drawings, the thicknesses are enlarged to clearly represent a plurality of layers and regions. And in the drawings, for the convenience of explanation, the thicknesses of some layers and regions are exaggeratedly shown.

[0014] Also, when a part such as a layer, film, region, plate, etc. is “above” another part, this includes not only the case where it is “directly above” another part but also the case where there are other parts in between. Conversely, when a part is “directly above” another part, it means that there are no other parts in between. Also, being “above” a reference part means being located above or below the reference part, and does not necessarily mean being located “above” in the direction opposite to gravity.

[0015] Also, throughout the specification, when a part “includes” a certain component, this means that, unless there is a contrary description, it does not exclude other components but can further include other components.

[0016] Also, throughout the specification, when it is said “on a plane”, this means when the target part is viewed from above, and when it is said “in a cross-section”, this means when the cross-section obtained by vertically cutting the target part is viewed from the side.

[0017] Furthermore, expressions written in the singular can be interpreted as singular or plural unless explicitly stated as "one" or "single." Terms containing ordinal numbers, such as "first" and "second," can be used to describe various components, but the components are not limited by such terms. These terms can be used to distinguish one component from another.

[0018] The following examples illustrate this disclosure in more detail. These examples are for illustrative purposes only and do not limit the scope of rights protected by this disclosure.

[0019] Figure 1 is a conceptual diagram showing a stylus pen and an electronic device.

[0020] Referring to Figure 1, the stylus pen 10 can receive signals output from the electronic device 2 or the touchscreen 20 near the touchscreen 20 of the electronic device 2 and transmit signals to the touchscreen 20.

[0021] Figure 2 is a schematic diagram illustrating the signal transmission operation between a stylus pen and an electronic device.

[0022] Referring to Figure 2, the touchscreen 20a may include a window 21, a touch electrode layer 22, a display panel 23, and a digitizer 24.

[0023] In the case of a passive stylus pen, specifically an EMR (Electro-Magnetic Resonance) type stylus pen 10, when a digitizer 24 transmits a magnetic signal B to the EMR type stylus pen 10, the resonant circuit contained within the stylus pen 10 can resonate with the magnetic signal B. The digitizer 24 can receive the resonated magnetic signal B as input from the stylus pen 10.

[0024] The digitizer 24 may be attached beneath the display panel 23 and may include a Flexible Printed Circuit Board (FPCB) with multiple conductive antenna loops formed therein, and a ferrite sheet that blocks the magnetic field generated by the antenna loops and blocks eddy currents that may be generated by other electrical elements when the antenna loops form a magnetic field.

[0025] An FPCB may consist of multiple layers of antenna loops for sensing the position where the resonant signal is input. Each antenna loop has a configuration that overlaps with at least one other antenna loop in the Z-axis direction. As a result, the thickness of the FPCB may increase, making it difficult to miniaturize the electronic device (2 in Figure 1) that contains the digitizer 24.

[0026] In one embodiment, when the digitizer 24 is mounted on the foldable / flexible electronic device 2, deformation may occur in the FPCB attached to the folding area. Repeated folding may stress the wiring members that form the antenna loop, eventually leading to damage to the wiring members. Furthermore, folding of the electronic device 2 may cause deformation of the ferrite sheet.

[0027] Figure 3 is a schematic diagram illustrating the signal transmission operation between a stylus pen and an electronic device.

[0028] In the case of a stylus pen 10 that includes a resonant circuit, when the electrodes of the touch electrode layer 32 transmit a magnetic signal B to the stylus pen 10, the resonant circuit included in the stylus pen 10 can resonate based on the magnetic signal B. The electrodes of the touch electrode layer 32 can receive the resonated magnetic signal input from the stylus pen 10.

[0029] Compared to the touchscreen (20a in Figure 2), the touchscreen 20b does not require additional units or modules such as a digitizer (24 in Figure 2) to transmit magnetic signals to the stylus pen 10, thus allowing for an even thinner touchscreen 20b. Furthermore, because the touchscreen 20b does not utilize the expensive digitizer 24, it may be more cost-effective than the touchscreen 20a in terms of manufacturing costs.

[0030] However, the internal resistance of the touch electrode layer 32 may be greater than the internal resistance of the digitizer 24. Generally, the internal resistance of the touch electrode layer 32 is more than 10 times greater than the internal resistance of the digitizer 24, so the drive current flowing through the touch electrode layer 32 may be more than 10 times lower than the drive current flowing through the digitizer 24.

[0031] When the drive current flowing through the touch electrode layer 32 decreases, the magnetic signal received by the stylus pen 10 from the touch electrode layer 32 decreases, and the resonant signal generated by the stylus pen 10 may also decrease.

[0032] The following describes the structure of the stylus pen 10 to compensate for the low magnetic signal transmitted to the stylus pen 10 by the resistance of the touch electrode layer 32.

[0033] Figure 4 is a diagram showing a stylus pen.

[0034] Referring to Figure 4, the stylus pen 10 includes a resonant circuit section 12 within its housing. The resonant circuit section 12 is an LC resonant circuit and can resonate with the drive signal output from the touchscreen 20. The drive signal may include a signal having a frequency corresponding to the resonant frequency of the resonant circuit section 12 (e.g., a sine wave, a square wave, etc.). For resonance to occur, the resonant frequency of the resonant circuit section 12 and the frequency of the drive signal must be the same or very similar. The resonant frequency of the stylus pen 10 can follow the design value of the resonant circuit section 12 of the stylus pen 10. When the touch electrode layer (32 in Figure 3) generates a magnetic field due to the drive signal, the resonant circuit section 12 of the stylus pen 10 can resonate using the signal received through the change in the magnetic field.

[0035] The elements of the stylus pen 10 can be housed in a housing. The housing can have various forms, including cylindrical, polygonal prism, a columnar form with at least a curved surface, an entasis form, a frustum of pyramid form, a circular truncated cone form, and so on, and its form is not limited. Since the housing is hollow inside, elements of the stylus pen 10, such as the resonant circuit section 12, can be housed inside. Such a housing can be made of a non-conductive material.

[0036] As shown in Figure 4, the EMR type stylus pen 10 may include a core body 11 and a resonant circuit section 12. The resonant circuit section 12 may include an inductor section 14 and a capacitor section 13. The inductor section 14 may include a ferrite core 15 through which the core body 11 passes and a coil 16 wound on the outer surface of the ferrite core 15.

[0037] The core body 11 may have one end that is the end of the pen and protrudes from the ferrite core 15. The core body 11 may consist of an electrode core made of a conductor, such as a conductive metal or a hard resin mixed with conductive powder.

[0038] The ferrite core 15 may have, for example, a cylindrical ferrite material with an axial through hole of a predetermined diameter (e.g., 1 mm) formed therein for inserting and passing the core body 11 through.

[0039] The coil 16 can be wound over the entire axial length of the ferrite core 15, or over a portion of its length. For example, the coil 16 can be wound around the ferrite core 15 at a distance of 2 mm from both axial sides of the ferrite core 15. The coil 16 can also be electrically connected to the capacitor section 13.

[0040] The capacitor section 13 may include multiple capacitors connected in parallel. Each capacitor on the printed circuit board may have a different capacitance and may be trimmed during the manufacturing process.

[0041] Figures 5 and 6 are conceptual diagrams that specifically show the inductor section of the stylus pen.

[0042] Referring to Figure 5, the inductor section 14 can include a ferrite core 15 and a coil 16 wound around the ferrite core 15. The inductance of the inductor section 14 is given by L = μSN. 2 / l is proportional to the magnetic coefficient (μ), the cross-sectional area (S) of coil 16, and the square of the number of windings (N), and inversely proportional to the length (l) of coil 16.

[0043] Although the ferrite core 15 is shown to be cylindrical, the ferrite core 15 can also have a polygonal prism, a prism with at least a curved surface, an entasis form, a frustum of a pyramid, a frustum of a cone, and other forms, and its form is not limited.

[0044] Referring to Figure 6, the inductor section 14 may include a ferrite core 15, a bobbin 17 surrounding at least a portion of the ferrite core 15, and a coil 16 wound around at least a portion of the bobbin 17. The force from the winding of the coil 16 can cause the bobbin 17 to be tightly fixed to the ferrite core 15. Such a bobbin 17 may include plastic or a metal with an insulated surface. Specifically, the bobbin 17 can be made of polyphenylene sulfide (PPS), liquid crystal polyester (LCP), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), and phenolic resins.

[0045] Due to the high dielectric constant of the ferrite core 15, parasitic capacitances Cp1 and Cp2 are generated between the ferrite core 15 and the coil 16. However, when the bobbin 17 surrounds the ferrite core 15 and the bobbin 17 is wound with the coil 16, the distance between the ferrite core 15 and the coil 16 increases. Therefore, the value of parasitic capacitance Cp2 in Figure 6 is smaller than the value of parasitic capacitance Cp1 in Figure 5.

[0046] Furthermore, the maximum amplitude of the resonant signal generated based on the inductor section 14 including the parasitic capacitance Cp2 may be greater than the maximum amplitude of the resonant signal generated based on the inductor section 14 including the parasitic capacitance Cp1.

[0047] Figures 7 through 10 are diagrams showing the number of twist turns in a coil.

[0048] Referring to Figures 5 through 10, the coil (16 in Figure 5) may be Litz wire cables 71, 81, 91, and 101 containing six metal wires 1, 2, 3, 4, 5, and 6. The six metal wires 1, 2, 3, 4, 5, and 6 may be twisted in a manner that rotates along the X direction.

[0049] The number of twist turns per unit length of coil 16 can mean the number of times, based on the unit length of the ferrite core (15 in Figure 5), that the multiple metal wires 1, 2, 3, 4, 5, and 6 contained in coil 16 are wound from one point on the outer surface of ferrite core 15, through other points, and back to the same point.

[0050] For example, if one of the six metal wires 1, 2, 3, 4, 5, and 6, metal wire 1, is positioned along the X direction of the ferrite core 15, moving from one point on the boundary to another point and then back to the same point, the number of twist turns of the coil 16 can be increased by +1N.

[0051] In Figure 7, the metal wire 1 moves from one point on the boundary to another point and back to the same point five times along the X-direction of the Litz wire cable 81 within 1 cm, so the number of twist turns of the coil 16 per unit length can be 5 N / cm. Similarly, in Figure 8, the metal wire 1 moves from one point on the boundary to another point and back to the same point ten times along the X-direction of the Litz wire cable 91 within 1 cm, so the number of twist turns of the coil 16 per unit length can be 10 N / cm. In Figure 9, the metal wire 1 moves from one point on the boundary to another point and back to the same point fifteen times along the X-direction of the Litz wire cable 91 within 1 cm, so the number of twist turns of the coil 16 per unit length can be 15 N / cm. In Figure 10, the metal wire 1 moves from one point on the boundary to another point and back to the same point twenty times along the X-direction of the Litz wire cable 101 within 1 cm, so the number of twist turns of the coil 16 per unit length can be 20 N / cm.

[0052] For the sake of explanation, Litz wire cables 71, 81, 91, and 101, which have a number of twist turns of coil 16 per unit length of iN / cm (where i is a positive integer), will be referred to as iN Litz wire cables. In this case, the number of twist turns of coil 16 per unit length and the unit length that serves as the basis for the number of twist turns of coil 16 are merely illustrative examples.

[0053] Figure 11 is a cross-sectional view of a coil according to one embodiment.

[0054] Referring to Figures 4 to 10, the coil 16 may be a Litz wire cable comprising a plurality of metal wires 162 and an insulating coating layer 161 surrounding the plurality of metal wires 162. In a Litz wire cable, each metal wire 162 is individually insulated by an insulating layer 163, which minimizes the skin effect, a phenomenon in which alternating current (AC) current flows concentrated near the surface of the conductor. In addition, the current flowing through the Litz wire cable can be uniformly distributed among the plurality of metal wires 162, and interference from magnetic fields can be reduced.

[0055] The diameter (T) of the coil 16 may vary depending on the number of metal wires 162, the wire diameter (φ) of the metal wires 162, the thickness (t) of the coating layer of the metal wires 162, or the thickness of the insulating coating layer 161.

[0056] The standard for Litz wire cable may be specified as N / xx. N may represent the number of 162 metal wires contained in the Litz wire cable, and xx may represent the diameter (φ) of the 162 metal wires.

[0057] Referring to Figure 11, the coil 16 includes seven metal wires 162, and of the seven metal wires 162, one central metal wire 162b is located in the center of the coil. Referring to Figures 7 to 10, the metal wires 162, excluding the central metal wire 162b, can be twisted in a manner that rotates along the X direction. However, the central metal wire 162b may not be twisted and may extend in a linear manner along the X direction. For this reason, the central metal wire 162b does not have to be included in the metal wire 162 that serves as the basis for the number of twist turns of the coil 16.

[0058] Figure 12 is a cross-sectional view of a coil according to a comparative example.

[0059] Referring to Figures 4 to 12, the coil 16 may be a Litz wire cable including a plurality of metal wires 162 and an insulating coating layer 161 surrounding the plurality of metal wires 162. In the Litz wire cable, each metal wire 162 may be individually insulated by an insulating layer 163.

[0060] The multiple metal wires 162 may include seven central metal wires 162b located in the center of the coil. The metal wires 162, excluding the central metal wires 162b, may be twisted in a manner that rotates along the X direction. However, the central metal wires 162b may not be twisted and may extend in a linear manner along the X direction. The metal wires 162 that serve as the basis for the number of twist turns of the coil 16 include only the outermost metal wires 162, and therefore, the central metal wires 162b do not need to be included in the metal wires 162 that serve as the basis for the number of twist turns of the coil 16.

[0061] The number of metal wires 162 included in the coil and the number of metal wires 162 that serve as the basis for the number of twist turns of coil 16 are merely examples. However, the more metal wires 162 included in the coil, the greater the number of central metal wires 162b may be. However, even in such cases, the number of twist turns of coil 16 can be determined based on the outermost metal wires 162, excluding the central metal wires 162b.

[0062] Figure 13 is a graph showing the Q value of an inductor section with respect to frequency according to one embodiment.

[0063] Specifically, Figure 13 shows the Q values ​​of three inductor section samples (14 in Figure 4) containing 5N Litz wire cable and three inductor section samples 14 containing 15N Litz wire cable, respectively, in the frequency band from 0kHz to 2000kHz.

[0064] Referring to Figure 13, the Q value of the inductor section 14 sample using 5N Litz wire cable has its maximum value at a frequency of 500 kHz, and the Q value at 500 kHz may be 175. In the frequency range above 500 kHz, the Q value of the inductor section 14 gradually decreases, and the Q value of the inductor section 14 may be 140 at a frequency of 2000 kHz. At this time, the Q values ​​of all three inductor section 14 samples, including the 5N Litz wire cable, can be measured to be similar.

[0065] The Q value of the inductor section 14 samples using 15N Litz wire cable has its maximum value at 1000 kHz, and the Q value at 1000 kHz may be 230. In the frequency range above 1000 kHz, the Q value of the inductor section 14 gradually decreases, and the Q value of the inductor section 14 may be 170 at a frequency of 2000 kHz. At this time, the Q values ​​of the three inductor section 14 samples, including the 15N Litz wire cable, can all be measured to be similar.

[0066] In the 0kHz to 2000kHz frequency band, the Q value of the inductor section 14 using a 15N Litz wire cable may be higher than the Q value of the inductor section 14 using a 5N Litz wire cable. For this reason, the magnitude of the magnetic signal resonating in the stylus pen (10 in Figure 4) including the inductor section 14 using a 15N Litz wire cable may be greater than the magnitude of the magnetic signal resonating in the stylus pen 10 including the inductor section 14 using a 5N Litz wire cable.

[0067] The higher the magnetic signal received by the touch electrode layer 32 from the stylus pen 10, the higher the SNR (Signal to Noise Ratio) can be. A high SNR means that the touchscreen (20b in Figure 3) receives less noise from the magnetic signal from the stylus pen 10, allowing the touch electrode layer 32 to accurately sense the position where the stylus pen 10 touches the touchscreen (Figure 20b). Furthermore, the higher the magnetic signal received by the touchscreen (Figure 20b) from the stylus pen 10, the smaller the minimum voltage required for the touchscreen 20b to sense the magnetic signal, allowing the touchscreen 20b to operate at low power. For this reason, a stylus pen 10 including an inductor section 14 using a 15N Litz wire cable allows the touchscreen 20b to sense the touch position of the stylus pen 10 more accurately and operate at lower power than a stylus pen 10 including an inductor section 14 using a 5N Litz wire cable.

[0068] Figure 14 is a diagram showing the inductance, resistance, and Q value of an inductor section including a coil according to a comparative example, and Figure 15 is a diagram showing the inductance, resistance, and Q value of an inductor section including a coil according to one embodiment.

[0069] Referring to Figure 14, the average L value of the three inductor sections (14 in Figure 4) samples, including the 5N Litz wire cable, may be 119.75 (H), the average R value may be 2.46 (Ω), and the average Q value may be 183.5.

[0070] Referring to Figure 15, the average L value of the three inductor sections (14 in Figure 4) samples, including the 15N Litz wire cable, may be 120.36 (H), the average R value may be 2.26 (Ω), and the average Q value may be 200.9.

[0071] The Q value of the inductor section 14 is given by 2πFL / R, which is proportional to the frequency (F) and inductance (L), and inversely proportional to the resistance (R). The average R value of three inductor section 14 samples including a 15N Litz wire cable is 2.26 (Ω), and the average R value of three inductor section 14 samples including a 5N Litz wire cable is 2.46 (Ω). Therefore, the average Q value of three inductor section 14 samples including a 15N Litz wire cable may be higher than the average Q value of three inductor section 14 samples including a 5N Litz wire cable. This is because the resistance R value becomes even lower as the number of twist turns of the coil (16 in Figure 5) increases. Since the number of twist turns of the 15N Litz wire cable is greater than that of the 5N Litz wire cable, the R value of the inductor section 14 including the 15N Litz wire cable may be lower than the R value of the inductor section 14 including the 5N Litz wire cable. Therefore, the Q value of the 14 samples of the 3 inductors containing a 15N Litz wire cable may be higher than the Q value of the 14 samples of the 3 inductors containing a 5N Litz wire cable.

[0072] Figure 16 is a graph showing the Q value of the inductor section based on the number of twist turns of the coil at a frequency of 600 kHz.

[0073] Referring to Figure 16, the Q value of the inductor section (14 in Figure 4) containing the 5N Litz wire cable may have a large deviation. When the Q value of the inductor section 14 was measured every second for 5 seconds, the Q values ​​of the inductor section 14 could be measured as 190, 196, 189, 199, and 190, respectively. It can be seen that the Q value of the inductor section 14 containing the 5N Litz wire cable has a larger deviation than the Q values ​​of the inductor sections 14 containing the 10N Litz wire cable, 15N Litz wire cable, and 20N Litz wire cable. Because the 5N Litz wire cable has a relatively small number of twist turns compared to the 10N, 15N, and 20N Litz wire cables, the metal wires (162 in Figure 11) of the inductor section 14 containing the 5N Litz wire cable may become disordered, which can cause problems with cold solder joints during soldering.

[0074] When the Q value of the inductor section 14, including the 20N Litz wire cable, was measured every second for 5 seconds, the Q values ​​of the inductor section 14 could be measured as 202, 201, 205, 204, and 201, respectively. The Q value of the inductor section 14, including the 20N Litz wire cable, was measured to be 200 or higher for 5 seconds, and may be higher than the Q value of the inductor section 14, including the 5N Litz wire cable. However, because the 20N Litz wire cable has a relatively larger number of twist turns compared to the 5N, 10N, and 15N Litz wire cables, insulation layer breakdown may occur due to the restoring inertia of the metal wire 162 in the inductor section 14, including the 20N Litz wire cable.

[0075] When the Q values ​​of the inductor section 14, including the 10N Litz wire cable, were measured every second for 5 seconds, the Q values ​​of the inductor section 14 could be measured as 196, 198, 199, 200, and 199, respectively. When the Q values ​​of the inductor section 14, including the 15N Litz wire cable, were measured every second for 5 seconds, the Q values ​​of the inductor section 14 could be measured as 205, 202, 203, 204, and 204, respectively.

[0076] The Q values ​​of the inductor section 14 including a 10N Litz wire cable and the Q values ​​of the inductor section 14 including a 15N Litz wire cable can be measured to be close to 200 in 5 seconds. Because the inductor section 14 including a 10N Litz wire cable and the inductor section 14 including a 15N Litz wire cable have more twist turns than the inductor section 14 including a 5N Litz wire cable, the probability of the metal wire 162 becoming distorted can be reduced. Because the inductor section 14 including a 10N Litz wire cable and the inductor section 14 including a 15N Litz wire cable have fewer twist turns than the inductor section 14 including a 20N Litz wire cable, the incidence of insulation layer breakdown due to the recovery inertia of the metal wire 162 can be reduced.

[0077] For this reason, the Litz wire cable included in the inductor section 14 may be a 10N Litz wire cable or a 15N Litz wire cable. However, since the Q value of the inductor section 14 including the 15N Litz wire cable, measured over 5 seconds, is always higher than the Q value of the inductor section 14 including the 10N Litz wire cable, it may be more preferable to use the 15N Litz wire cable in the inductor section 14.

[0078] Figure 17 is a diagram illustrating a U-type winding system.

[0079] Referring to Figure 17, the U-type winding scheme is a sequential layer winding scheme where, once the winding of the lower layer is completed (e.g., 1→2→3→4), the winding of the layer directly above it is started (e.g., 5→6→7→8). In this case, the U-type winding scheme allows the winding of the layer directly above to begin at the point where the winding of the previous layer ends (e.g., point 4). The U-type winding scheme is the simplest winding scheme, but because winding continues until the lower layer is completed, the length of the coil (l) can become long. Due to the length of the coil (l), the inductance becomes L=μSN 2 The Q value of the inductor section (14 in Figure 4) can be reduced by 2πFL / R due to the decrease in / l.

[0080] Figure 18 is a diagram illustrating a zigzag-type winding method.

[0081] The zigzag winding scheme shown in Figure 18 is an alternate layer winding scheme in which adjacent winding layers are wound alternately, and the windings of adjacent layers are wound at a zigzag angle. This zigzag winding scheme can minimize the voltage difference between adjacent winding layers, thereby reducing winding self-capacitance. However, winding with a zigzag winding scheme can make the structure of the inductor section (14 in Figure 4) unstable, potentially lowering the Q value of the inductor section 14.

[0082] Figure 19 is a graph showing the Q value of the inductor section measured by changing the frequency using a KEYSIGHT TECHNOGIES E4980A precision LCR meter.

[0083] Referring to Figure 19, waveform a shows the change in Q value with respect to frequency for the inductor section (14 in Figure 4) using a U-type winding method, and waveform b shows the change in Q value with respect to frequency for the inductor section 14 using a zigzag-type winding method. The Q value of the inductor section 14 made with a U-type winding method can reach its maximum value at a frequency of around 150 kHz (f1). The Q value of the inductor section 14 made with a zigzag-type winding method can reach its maximum value at a frequency of around 100 kHz (f2).

[0084] Referring to waveforms a and b in Figure 19, it can be seen that the maximum Q value of the inductor section 14 made with a zigzag winding method is approximately twice as high as the maximum Q value of the inductor section 14 made with a U-type winding method. Therefore, it can be seen that the zigzag winding method is superior to the U-type winding method for the inductor section 14 that forms the resonant circuit of the stylus pen (10 in Figure 4).

[0085] However, the maximum Q value of the inductor section 14 with a zigzag winding method may not reach the target Q value. It can be seen that the target Q value is about twice as high as the maximum Q value of the inductor section 14 manufactured with a zigzag winding method.

[0086] In one embodiment, the target Q value can be 200, the maximum Q value of the zigzag-type winding inductor section 14 is 100, and the maximum Q value of the U-type winding inductor section 14 is 50. In this case, because the magnitude of the magnetic signal resonating in the zigzag-type winding inductor section 14 and the U-type winding inductor section 14 is small, the touch electrode layer (32 in Figure 3) may have difficulty receiving the magnetic signal from the inductor section 14 and sensing the touch position of the stylus pen (10 in Figure 3) based on the received magnetic signal.

[0087] Figure 20 is a diagram illustrating an N-step type winding system.

[0088] Referring to Figure 20, the N-step type winding method can be a type of winding method that utilizes both the U-type winding method and the zigzag type winding method. Specifically, the N-step type winding method uses the sequential layer winding method of the U-type winding method, where winding of the layer directly above is started when the winding of the lower layer is finished, and winding of the layer directly above can begin at the point where the winding of the lower layer ends. However, the point where the winding of the lower layer ends may differ from that of the U-type winding method.

[0089] For example, in a U-type winding system, winding of the upper layer is done only after all the winding in the lower layer is completed. However, in an N-step type winding system, the lower layer is divided into N sections, and winding of the upper layer can be done only after winding is completed in each of the N divided lower layers. In this case, there may be multiple upper layers, and in such cases, winding can be done sequentially starting from the upper layers closest to the lower layers.

[0090] Furthermore, the N-step type winding method utilizes a zigzag type winding method in which adjacent winding layers are wound alternately, thereby minimizing the voltage difference between adjacent windings. However, the alternately wound winding layers may differ from those of the zigzag type winding method.

[0091] For example, in a zigzag winding method, all adjacent windings are wound alternately, but in an N-step winding method, among the N divided winding stacks 201, 202, 203, and 204, winding can be done from the 10th region of the 3rd layer of the 1st winding stack 201 to the 1st region of the 1st layer of the 2nd winding stack 202, from the 10th region of the 3rd layer of the 2nd winding stack 202 to the 1st region of the 1st layer of the 3rd winding stack 203, and from the 10th region of the 3rd winding stack 203 to the 1st region of the 1st layer of the 4th winding stack 204.

[0092] The number of steps (N) in an N-step winding system and the number of layers contained in each winding stack 201, 202, 203, and 204 may differ based on the Q value of the inductor. However, the number of steps (N) in an N-step winding system can be at least 3, taking into account the target Q value. A detailed explanation of the Q value of an N-step winding system follows in Figure 22.

[0093] Furthermore, if there are too many steps in the N-step type winding method, the structure may become unstable, which can affect the degradation of the Q value. For this reason, the number of steps (N) in the N-step type winding method can be limited to a maximum of 10 or fewer.

[0094] Figure 21 is a conceptual diagram showing the inductor section of a stylus pen that utilizes an N-step type winding method.

[0095] Referring to Figure 21, the inductor section 210 includes a ferrite core 211 and may include four winding stacks 212-a, 212-b, 212-c, and 212-d that wind the ferrite core 211. In one embodiment, the four winding stacks 212-a, 212-b, 212-c, and 212-d may also wind a bobbin (17 in Figure 6) that surrounds at least a portion of the ferrite core 211.

[0096] The inductor section 210 may include a first winding connection region 213-a connected between the first winding stack 212-a and the second winding stack 212-b, a second winding connection region 213-b connected between the second winding stack 212-b and the third winding stack 212-c, and a third winding connection region 213-c connected between the third winding stack 212-c and the fourth winding stack 212-d.

[0097] The first winding connection region 213-a is the region where the 3rd layer 10th region of the first winding stack (201 in Figure 20) and the 1st layer 1st region of the second winding stack (202 in Figure 20) are connected; the second winding connection region 213-b is the region where the 3rd layer 10th region of the second winding stack 202 and the 1st layer 1st region of the third winding stack (203 in Figure 20) are connected; and the third winding connection region 213-c may be the region where the 3rd layer 10th region of the third winding stack 203 and the 1st layer 1st region of the fourth winding stack (204 in Figure 20) are connected.

[0098] Figure 22 is a cross-sectional view of the inductor section of a stylus pen that uses an N-step type winding method.

[0099] Referring to Figure 22, the left region P01 of the ferrite core 220 of the inductor section (14 in Figure 4) is adjacent to the core body (11 in Figure 4), and the right region P06 of the ferrite core 220 may be adjacent to the capacitor (13 in Figure 4). The coil (16 in Figure 4) can be wound around the ferrite core 220 at a distance of 2 mm from the left region P01 and the right region P06 of the ferrite core 220 of the inductor section. This prevents the current flowing through the coil 16 from leaking into the core body 11 or the capacitor 13.

[0100] The ferrite core 220 is separated into multiple regions at regular intervals with respect to its axial direction, and coils can be wound individually in multiple regions. For example, region P02 may be the first winding stack region in which the first winding stack (201 in Figure 20) is wound on the ferrite core 220, region P03 may be the second winding stack region in which the second winding stack (202 in Figure 20) is wound on the ferrite core 220, region P04 may be the third winding stack region in which the third winding stack (203 in Figure 20) is wound on the ferrite core 220, and region P05 may be the fourth winding stack region in which the fourth winding stack (204 in Figure 20) is wound on the ferrite core 220.

[0101] Figure 23 is a diagram showing the Q value based on the number of twist turns and winding method.

[0102] Referring to Figures 16, 20, and 23, Sample 1 is an inductor section (14 in Figure 4) that utilizes a 15N Litz wire cable and an N-step type winding method, while Sample 2 may be an inductor section 14 that utilizes a 0N Litz wire cable and a zigzag type winding method.

[0103] The Q value of Sample 1, which uses a 15N Litz wire cable and an N-step type winding method, may be 200. On the other hand, the Q value of Sample 2, which uses a 0N Litz wire cable and a zigzag type winding method, may be 100. The Q value of Sample 1, which is configured based on a 15N twist turn count and an N-step type winding method for the Litz wire cable, may be greater than the Q value of Sample 2, which is configured based on either no twist turns in the Litz wire cable or a zigzag type winding method.

[0104] Since the stylus pen (10 in Figure 3) containing the inductor portion 14 of Sample 1 has a higher Q value than the stylus pen 10 containing the inductor portion 14 of Sample 2, the strength of the magnetic signal resonating in the inductor portion 14 of Sample 1 may be greater than the strength of the magnetic signal resonating in the inductor portion 14 of Sample 2.

[0105] The touch electrode layer (32 in Figure 3) can more accurately detect the position where the stylus pen 10 touches the touchscreen (20b in Figure 3) as it receives a stronger magnetic signal from the stylus pen 10. Furthermore, the stronger the magnetic signal the touchscreen (20b in Figure 3) receives from the stylus pen 10, the smaller the minimum voltage required for the touchscreen 20b to detect the magnetic signal becomes, allowing the touchscreen 20b to operate at low power.

[0106] To achieve this, the stylus pen 10 including the inductor unit 14 of Sample 1 allows the touchscreen 20b to accurately sense the touch position of the stylus pen 10 and enables the touchscreen 20b to operate at low power, compared to the stylus pen including the inductor unit 14 of Sample 2 (10 in Figure 3).

[0107] Although embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto. Various modifications and improvements made by those skilled in the art, utilizing the basic concepts of the present invention as defined in the claims, also fall within the scope of the present invention.

Claims

1. Ferrite core, and A coil comprising multiple metal wires twisted together such that the number of twist turns per unit length is 10N to 15N, wound around the outer surface of the ferrite core. Includes, The number of twist turns per unit length is the number of times the plurality of metal wires are wound from one point on the outer surface of the ferrite core, through other points, and back to the same point, in a stylus pen.

2. The aforementioned plurality of metal wires are The coil includes a central metal wire located in the center of the coil and a plurality of outer metal wires located on the outer casing of the coil, The number of twist turns per unit length is The number of times the plurality of outer metal wires are wound from one point on the outer surface of the ferrite core, through other points, and back to the same point. The stylus pen according to claim 1.

3. The aforementioned plurality of metal wires are The coil includes a plurality of central metal wires located in the center of the coil and a plurality of outer metal wires located in the outer casing of the coil, The number of twist turns per unit length is The number of times the plurality of outer metal wires are wound from one point on the outer surface of the ferrite core, through other points, and back to the same point. The stylus pen according to claim 1.

4. The aforementioned coil is The windings are arranged at a distance from each of the axial side ends of the ferrite core, The stylus pen according to claim 1.

5. The ferrite core is separated into multiple regions at regular intervals with respect to the axial direction of the ferrite core, and the coil is wound individually in the multiple regions. The stylus pen according to claim 4.

6. Each of the aforementioned multiple regions includes a lower region and an upper region positioned above the lower region, and when the winding of the lower region is completed, the winding of the upper region begins. The stylus pen according to claim 5.

7. The aforementioned upper region includes a first upper region and a second upper region. The first upper region is positioned on top of the lower region. The second upper region is positioned on top of the first upper region. The stylus pen according to claim 6.

8. The aforementioned coil is A bobbin is wound around at least a portion of the ferrite core. The stylus pen according to claim 6.

9. A stylus pen including an inductor section and a capacitor electrically connected to the inductor section, including a Litz wire cable containing multiple metal wires twisted in a rotatable manner on a portion of a ferrite core so that the number of twist turns per unit length is 10N to 15N; and A touchscreen including a touch electrode layer that receives electromagnetic signals resonated by the stylus pen; Includes, The number of twist turns per unit length is the number of times the plurality of metal wires are wound from one point on the outer surface of the ferrite core, through other points, and back to the same point, in a touch system.

10. The aforementioned plurality of metal wires are A portion of the ferrite core is twisted in a rotatable manner, with a distance of separation between each of the axial side ends of the ferrite core. The touch system according to claim 9.

11. The ferrite core is separated into multiple regions at regular intervals with respect to the axial direction of the ferrite core, The Litz wire cable is wound individually in the plurality of regions. The touch system according to claim 10.

12. Each of the aforementioned multiple regions includes a lower region and an upper region positioned above the lower region, and when the winding of the lower region is completed, the winding of the upper region begins. The touch system according to claim 11.

13. The Litz wire cable winds a first connecting region which is one of the plurality of regions and connects a first region and a second region adjacent to the first region. The touch system according to claim 12.

14. The first connecting region includes a connecting region in which the upper region of the first region and the lower region of the second region are connected by the Litz wire cable. The touch system according to claim 13.

15. The aforementioned Litz wire cable is A bobbin is wound around at least a portion of the ferrite core. The touch system according to claim 14.

16. An inductor section including a coil containing multiple metal wires wound in multiple steps on a portion of a ferrite core and twisted in such a manner that the number of twist turns per unit length is 10N to 15N; and A capacitor unit electrically connected to the aforementioned coil; Includes, The number of twist turns per unit length is the number of times the plurality of metal wires are wound from one point on the outer surface of the ferrite core, through other points, and back to the same point, in a touch system.

17. The coil, which is wound in multiple steps on a portion of the ferrite core, The ferrite core is wound in a plurality of winding stack regions and a plurality of winding connecting regions that connect each of the plurality of winding stack regions. The touch system according to claim 16.

18. The aforementioned multiple winding stack regions are, The ferrite core is separated into multiple regions by distances from both axial side ends of the ferrite core, and each of the multiple regions includes multiple layers on which the coil is wound. The touch system according to claim 17.

19. The aforementioned plurality of winding connection regions are A first winding stack region, which is one of the plurality of winding stack regions, and a second winding stack region adjacent to the first winding stack region are connected, and the first layer, which is the highest of the plurality of layers included in the first winding stack region, and the second layer, which is the lowest of the plurality of layers included in the second winding stack region, are connected. The touch system according to claim 18.

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