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 technology]

[0002] A variety of devices, such as mobile phones, smart phones, tablet PCs, laptop computers, digital broadcasting terminals, personal digital assistants (PDAs), portable multimedia players (PMPs), and navigation systems, are equipped with touch sensors.

[0003] In such a device, the touch sensor may be located on a display panel that displays images or in a region of the device body, and the device may provide an intuitive user interface to the user by allowing the user to interact with the device by touching the touch sensor.

[0004] A user can use a stylus pen for precise touch input, which can transmit and receive signals to and from a touch sensor through electrical and / or magnetic means. Summary of the Invention [Problem to be solved by the invention]

[0005] It is an object of one embodiment to provide a stylus pen for effectively receiving and transmitting magnetic signals from and to an 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 problem]

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

[0008] According to an embodiment, the touch system may include a stylus pen including an inductor portion including a Litz wire cable including a plurality of metal wires twisted in a rotating manner around a portion of a ferrite core, a capacitor electrically connected to the inductor portion, and a touch screen including a touch electrode layer that receives an electromagnetic signal resonated by the stylus pen.

[0009] According to an embodiment, the ferrite core may include an inductor unit including a coil including a plurality of metal wires wound in a plurality of steps and twisted in a rotating form around a portion of the ferrite core, and a capacitor unit electrically connected to the coil. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a conceptual diagram showing a stylus pen and an electronic device. [Diagram 2] 1 is a diagram illustrating a schematic diagram of a signal transmission operation between a stylus pen and an electronic device. [Diagram 3] 1 is a diagram illustrating a schematic diagram of a signal transmission operation between a stylus pen and an electronic device. [Figure 4] 1 is a diagram showing a stylus pen. [Diagram 5] FIG. 2 is a conceptual diagram specifically illustrating an inductor portion of the stylus pen. [Figure 6] FIG. 2 is a conceptual diagram specifically illustrating an inductor portion of the stylus pen. [Figure 7] 1 is a diagram showing the number of twist turns of a coil. [Figure 8] 1 is a diagram showing the number of twist turns of a coil. [Figure 9] 1 is a diagram showing the number of twist turns of a coil. [Figure 10] 1 is a diagram showing the number of twist turns of a coil. [Figure 11] FIG. 2 is a cross-sectional view of a coil according to one embodiment. [Figure 12] FIG. 11 is a cross-sectional view of a coil according to a comparative example. [Figure 13] 11 is a graph showing a Q value depending on the frequency of an inductor portion according to one embodiment. [Figure 14] 13 is a diagram showing the inductance, resistance, and Q value of an inductor section including a coil according to a comparative example. [Figure 15] 1 is a diagram showing the inductance, resistance, and Q value of an inductor unit including a coil according to an embodiment. [Figure 16] 1 is a graph showing the Q value of the inductor section depending on the number of twist turns of the coil at a frequency of 600 kHz. [Figure 17] 1 is a diagram showing a U-type winding method. [Figure 18] 1 is a diagram showing a zigzag type winding method. [Figure 19] This is a graph showing the Q value of an inductor measured by changing the frequency using a KEYSIGHT TECHNOGIES E4980A precision LCR meter. [Figure 20] 1 is a diagram showing an N-step type winding method. [Figure 21] FIG. 1 is a conceptual diagram showing an inductor part of a stylus pen that uses an N-step type winding method. [Figure 22] 1 is a cross-sectional view of an inductor part of a stylus pen that uses an N-step type winding method. [Diagram 23] 1 is a diagram showing the Q value according to the number of twist turns and the winding method. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will now be described in detail with reference to the accompanying drawings, in which: FIG. 1 is a block diagram of a semiconductor device according to an embodiment of the present invention;

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

[0013] In addition, the size and thickness of each component shown in the drawings are arbitrarily shown for convenience of explanation, and the present invention is not necessarily limited to those shown in the drawings. In the drawings, thicknesses are enlarged to clearly show multiple layers and regions. In the drawings, thicknesses of some layers and regions are exaggerated for convenience of explanation.

[0014] In addition, when a part such as a layer, film, region, or plate is said to be "above" another part, this includes not only the case where it is "directly above" the other part, but also the case where there is another part in between. Conversely, when a part is said to be "directly above" another part, it means that there is no other part in between. In addition, being "above" a reference part means being located above or below the reference part, and does not necessarily mean being located "above" the side opposite to gravity.

[0015] Additionally, throughout the specification, when a part is said to "comprise" a certain element, this means that it may further include other elements, not excluding other elements, unless specifically stated to the contrary.

[0016] Also, throughout the specification, a reference to "in a plane" means when the subject part is viewed from above, and a reference to "in cross section" means when the subject part is cut vertically and viewed from the side.

[0017] Additionally, expressions described in the singular can be interpreted as singular or plural unless an explicit expression such as "one" or "single" is used. Terms including ordinal numbers such as first, second, etc. can be used to describe various components, but the components are not limited by such terms. These terms can be used for the purpose of distinguishing one component from another component.

[0018] The present disclosure will be described in more detail below with reference to examples. These examples are merely for the purpose of illustrating the present disclosure, and the scope of protection of the present disclosure is not limited by these examples.

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

[0020] Referring to FIG. 1, a stylus pen 10 is disposed near a touch screen 20 of an electronic device 2 and can receive a signal output from the electronic device 2 or the touch screen 20 and transmit a signal to the touch screen 20 .

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

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

[0023] Among passive stylus pens, in 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, a resonant circuit included in the stylus pen 10 can resonate with the magnetic signal B. The digitizer 24 can receive an input of the resonated magnetic signal B from the stylus pen 10.

[0024] The digitizer 24 may be attached under the display panel 23 and may include a flexible printed circuit board (FPCB) on which a number of conductive antenna loops are formed, and a ferrite sheet that blocks the magnetic field generated by the antenna loops and blocks eddy currents that may be generated in other electrical elements when the antenna loops form a magnetic field.

[0025] The FPCB may have multiple antenna loops in multiple layers for detecting the position where the resonant signal is input. One antenna loop overlaps at least one other antenna loop in the Z-axis direction. This increases the thickness of the FPCB, making it difficult to miniaturize the electronic device (2 in FIG. 1) including the digitizer 24.

[0026] In some embodiments, when the digitizer 24 is mounted on the foldable / flexible electronic device 2, deformation may occur in the FPCB attached to the folded area. Repeated folding may cause stress to be applied to the wiring member forming the antenna loop, which may eventually cause damage to the wiring member. Additionally, folding of the electronic device 2 may cause deformation of the ferrite sheet.

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

[0028] In the case of the stylus pen 10 including a resonant circuit, when the electrode of the touch electrode layer 32 transmits 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 electrode of the touch electrode layer 32 can receive an input of the resonated magnetic signal from the stylus pen 10.

[0029] Compared with the touchscreen (20a in FIG. 2), the thickness of the touchscreen 20b can be further reduced because the touchscreen 20b does not require an additional unit or module such as a digitizer (24 in FIG. 2) for transmitting a magnetic signal to the stylus pen 10. In addition, since the touchscreen 20b does not use the expensive digitizer 24, the manufacturing cost of the touchscreen 20b may be more advantageous than that of the touchscreen 20a.

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

[0031] When the driving current flowing through the touch electrode layer 32 becomes lower, the magnetic signal received by the stylus pen 10 from the touch electrode layer 32 becomes lower, and the resonant signal generated by the stylus pen 10 may also become lower.

[0032] The structure of the stylus pen 10 for compensating for the low magnetic signal transmitted to the stylus pen 10 by the resistance of the touch electrode layer 32 will be described below.

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

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

[0035] The elements of the stylus pen 10 may be housed in a housing. The housing may have a shape such as a cylinder, a polygonal prism, a cylinder with at least a portion curved, an entasis shape, a frustum of pyramid, a circular truncated cone, etc., and the shape is not limited thereto. The housing has an open interior, so that the elements of the stylus pen 10, such as the resonant circuit unit 12, can be housed therein. Such a housing may be made of a non-conductive material.

[0036] 4, the EMR type stylus pen 10 may include a core 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 11 passes and a coil 16 wound on the outer surface of the ferrite core 15.

[0037] One end of the core 11 may be the end of the pen and protrude from the ferrite core 15. The core 11 may be composed of an electrode core made of a conductor, for example, a hard resin mixed with a conductive metal or conductive powder.

[0038] The ferrite core 15 may be, for example, a cylindrical ferrite material, and may have a through hole with a predetermined diameter (for example, 1 mm) formed in the axial direction for inserting and passing the core body 11 therethrough.

[0039] The coil 16 may be wound over the entire length of the ferrite core 15 in the axial direction or over a portion of the length. For example, the coil 16 may be wound around the ferrite core 15 at a distance of 2 mm from both side ends of the ferrite core 15 in the axial direction. The coil 16 may also be electrically connected to the capacitor unit 13.

[0040] The capacitor unit 13 may include a plurality of 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] 5 and 6 are conceptual diagrams specifically showing the inductor portion of the stylus pen.

[0042] 5, the inductor unit 14 may include a ferrite core 15 and a coil 16 wound around the ferrite core 15. The inductance of the inductor unit 14 is expressed as L=μSN. 2 / l, it is proportional to the square of the magnetic coefficient (μ), the cross-sectional area (S) of the coil 16, and the number of turns (N), and inversely proportional to the length (l) of the coil 16.

[0043] Although the ferrite core 15 is shown to have a cylindrical shape, the ferrite core 15 may also have a polygonal column, a column shape having at least a curved surface in at least a portion, an entasis shape, a truncated pyramid shape, a truncated cone shape, etc., and the shape is not limited thereto.

[0044] 6, the inductor unit 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 bobbin 17 may be tightly fixed to the ferrite core 15 by the force of the winding of the coil 16. The bobbin 17 may include plastic or a metal with an insulating surface. In particular, the bobbin 17 may be made of polyphenylene sulfide (PPS), liquid crystal polyester (LCP), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), phenolic resin, etc.

[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, but when the bobbin 17 surrounds the ferrite core 15 and is wound with the coil 16, the distance between the ferrite core 15 and the coil 16 increases. Therefore, the value of the parasitic capacitance Cp2 in FIG. 6 is smaller than the value of the parasitic capacitance Cp1 in FIG. 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] 7 to 10 are diagrams showing the number of twist turns of the coil.

[0048] 5 to 10, the coil (16 in FIG. 5) may be a Litz wire cable 71, 81, 91, 101 including 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 rotating manner along the X direction.

[0049] The number of twisted turns per unit length of coil 16 may refer to the number of times that the multiple metal wires 1, 2, 3, 4, 5, and 6 included in coil 16 are wound from one point on the outer surface of ferrite core 15 to another point and then back to one point again per unit length of ferrite core 15, based on the unit length of the ferrite core (15 in FIG. 5).

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

[0051] The metal wire 1 in FIG. 7 is located 5 times from one point on the boundary to another point along the X direction of the litz wire cable 81 in 1 cm, so the number of twist turns of the coil 16 per unit length may be 5 N / cm. Similarly, the metal wire 1 in FIG. 8 is located 10 times from one point on the boundary to another point along the X direction of the litz wire cable 91 in 1 cm, so the number of twist turns of the coil 16 per unit length may be 10 N / cm. The metal wire 1 in FIG. 9 is located 15 times from one point on the boundary to another point along the X direction of the litz wire cable 91 in 1 cm, so the number of twist turns of the coil 16 per unit length may be 15 N / cm. The metal wire 1 in FIG. 10 is located 20 times from one point on the boundary to another point along the X direction of the litz wire cable 101 in 1 cm, so the number of twist turns of the coil 16 per unit length may be 20 N / cm.

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

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

[0054] 4 to 10, 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 is individually insulated by an insulating layer 163, and it is possible to minimize the skin effect, which is a phenomenon in which an alternating current (AC) current flows in a concentrated manner near the surface of a conductor. In addition, the current flowing in the Litz wire cable can be uniformly distributed to the plurality of metal wires 162, and interference of a magnetic field can be reduced.

[0055] The diameter (T) of the coil 16 can 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 of the Litz wire cable may be specified as N / xx, where N means the number of metal wires 162 contained in the Litz wire cable, and xx means the wire diameter (φ) of the metal wires 162.

[0057] 11, the coil 16 includes seven metal wires 162, and among the seven metal wires 162, one central metal wire 162b may be located at the center inside the coil. Referring to FIGS. 7 to 10, the metal wires 162 except for the central metal wire 162b may be twisted in a rotating manner along the X direction. However, the central metal wire 162b may not be twisted and may extend linearly along the X direction. For this reason, the central metal wire 162b may not be included in the metal wires 162 that are the basis for the number of twist turns of the coil 16.

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

[0059] 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 plurality of metal wires 162 may include seven central metal wires 162b located at the center inside the coil. The metal wires 162 except for the central metal wire 162b may be twisted in a rotating form along the X direction. However, the central metal wire 162b may not be twisted and may extend in a straight form along the X direction. The metal wires 162 that are the basis for the number of twist turns of the coil 16 include only the metal wires 162 located at the outermost periphery, and therefore the central metal wire 162b may not be included in the metal wires 162 that are 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 used as a reference for the number of twist turns of the coil 16 are merely examples. However, the more metal wires 162 included in the coil, the more central metal wires 162b may be included. However, even in this case, the number of twist turns of the coil 16 may be determined based on the metal wires 162 located on the outermost periphery excluding the central metal wires 162b.

[0062] FIG. 13 is a graph showing the Q value depending on the frequency of the inductor section according to one embodiment.

[0063] Specifically, FIG. 13 shows the Q values ​​of three inductor unit samples (14 in FIG. 4) including 5N Litz wire cables and three inductor unit samples 14 including 15N Litz wire cables in the 0 kHz to 2000 kHz frequency band.

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

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

[0066] The Q value of inductor section 14 using a 15N Litz wire cable in the 0 kHz to 2000 kHz frequency band may be higher than the Q value of inductor section 14 using a 5N Litz wire cable. Therefore, the magnitude of the magnetic signal resonated in the stylus pen (10 in FIG. 4) including inductor section 14 using the 15N Litz wire cable may be higher than the magnitude of the magnetic signal resonated in stylus pen 10 including inductor section 14 using the 5N Litz wire cable.

[0067] The higher the magnetic signal that the touch electrode layer 32 receives from the stylus pen 10, the higher the SNR (Signal to Noise Ratio) can be. Higher SNR means that the touch screen (20b in FIG. 3) receives less noise in the magnetic signal from the stylus pen 10, so the touch electrode layer 32 can accurately detect the position where the stylus pen 10 touches the touch screen (FIG. 20b). In addition, the higher the magnetic signal that the touch screen (FIG. 20b) receives from the stylus pen 10, the smaller the minimum voltage of the touch screen 20b for detecting the magnetic signal can be, so the touch screen 20b can operate with lower power. For this reason, the stylus pen 10 including the inductor unit 14 using a 15N Litz wire cable can allow the touch screen 20b to detect the touch position of the stylus pen 10 more accurately and operate with lower power than the stylus pen 10 including the inductor unit 14 using a 5N Litz wire cable.

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

[0069] Referring to FIG. 14, the average L value of the three inductor section (14 in FIG. 4) samples including 5N Litz wire cables is 119.75 (H), the average R value is 2.46 (Ω), and the average Q value is 183.5.

[0070] Referring to FIG. 15, the average L value of the three inductor section (14 in FIG. 4) samples including 15N Litz wire cables is 120.36 (H), the average R value is 2.26 (Ω), and the average Q value is 200.9.

[0071] The Q value of the inductor section 14 is proportional to the frequency (F) and inductance (L) and inversely proportional to the resistance (R) according to 2πFL / R. Since the average R value of the three inductor section 14 samples including the 15N Litz wire cable is 2.26 (Ω) and the average R value of the three inductor section 14 samples including the 5N Litz wire cable is 2.46 (Ω), the average Q value of the three inductor section 14 samples including the 15N Litz wire cable may be higher than the average Q value of the three inductor section 14 samples including the 5N Litz wire cable. This is because the resistance R value becomes lower as the number of twisted turns of the coil (16 in FIG. 5) increases. Since the number of twisted turns of the 15N Litz wire cable is greater than the number of twisted turns 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 three inductor section 14 samples including the 15N Litz wire cable may be higher than the Q value of the three inductor section 14 samples including the 5N Litz wire cable.

[0072] FIG. 16 is a graph showing the Q value of the inductor section as a function of the number of twist turns of the coil at a frequency of 600 kHz.

[0073] 16, the Q value of the inductor unit 14 including the 5N Litz wire cable (14 in FIG. 4) may have a large deviation. As a result of measuring the Q value of the inductor unit 14 every second for five seconds, the Q values ​​of the inductor unit 14 are measured to be 190, 196, 189, 199, and 190, respectively. It can be seen that the Q value of the inductor unit 14 including the 5N Litz wire cable has a larger deviation than the Q values ​​of the inductor unit 14 including the 10N Litz wire cable, the 15N Litz wire cable, and the 20N Litz wire cable. Since the 5N Litz wire cable has a relatively smaller number of twist turns compared to the 10N, 15N, and 20N Litz wire cables, the metal wire (162 in FIG. 11) of the inductor unit 14 including the 5N Litz wire cable may become disordered, which may cause a problem of cold solder joint during soldering.

[0074] As a result of measuring the Q value of the inductor section 14 including the 20N litz wire cable every second for 5 seconds, the Q values ​​of the inductor section 14 may be measured as 202, 201, 205, 204, and 201, respectively. The Q value of the inductor section 14 including the 20N litz wire cable may be constantly measured as 200 or more for 5 seconds, which is higher than the Q value of the inductor section 14 including the 5N litz wire cable. However, since the 20N litz wire cable has a relatively large 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 of the inductor section 14 including the 20N litz wire cable.

[0075] When the Q-factor of inductor section 14 including a 10N Litz wire cable is measured every second for 5 seconds, the Q-factors of inductor section 14 can be measured as 196, 198, 199, 200, and 199. When the Q-factor of inductor section 14 including a 15N Litz wire cable is measured every second for 5 seconds, the Q-factors of inductor section 14 can be measured as 205, 202, 203, 204, and 204, respectively.

[0076] The Q value of the inductor section 14 including the 10N Litz wire cable and the Q value of the inductor section 14 including the 15N Litz wire cable can be measured to be close to 200 in 5 seconds. Since the inductor section 14 including the 10N Litz wire cable and the inductor section 14 including the 15N Litz wire cable have a larger number of twist turns than the inductor section 14 including the 5N Litz wire cable, the probability of the metal wire 162 becoming distorted can be reduced. Since the inductor section 14 including the 10N Litz wire cable and the inductor section 14 including the 15N Litz wire cable have a smaller number of twist turns than the inductor section 14 including the 20N Litz wire cable, the occurrence rate of insulation layer breakdown due to the restoring inertia of the metal wire 162 can be reduced.

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

[0078] FIG. 17 is a diagram showing a U-type winding method.

[0079] Referring to FIG. 17, the U-type winding scheme is a sequential layer winding scheme in which the winding of the upper layer is started (e.g., 5→6→7→8) after the winding of the lower layer is finished (e.g., 1→2→3→4). In this case, the U-type winding scheme allows the winding of the upper layer to start 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 the coil length (l) can be long because winding is continued until the lower layer is finished. As the coil length (l) becomes longer, the inductance becomes L=μSN 2 / l, and the Q value of the inductor section (14 in FIG. 4) can be lowered by 2πFL / R.

[0080] FIG. 18 is a diagram showing a zigzag type winding method.

[0081] The zigzag type winding scheme of Fig. 18 is an alternate layer winding scheme in which adjacent winding layers are alternately wound, and adjacent layers are wound with a zigzag inclination. This zigzag type winding scheme can minimize the voltage difference between the windings of adjacent layers, thereby reducing the winding self-capacitance. However, if winding is performed using the zigzag type winding scheme, the structure of the inductor unit (14 in Fig. 4) may become unstable, and the Q value of the inductor unit 14 may become low.

[0082] FIG. 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] 19, waveform a is a waveform showing the change in Q value versus frequency of the inductor unit (14 in FIG. 4) using a U-type winding method, and waveform b is a waveform showing the change in Q value versus frequency of the inductor unit 14 using a zigzag-type winding method. The Q value of the inductor unit 14 manufactured using the U-type winding method may have a maximum value at a frequency (f1) near 150 kHz. The Q value of the inductor unit 14 manufactured using the zigzag-type winding method may have a maximum value at a frequency (f2) near 100 kHz.

[0084] 19, it can be seen that the maximum Q value of inductor section 14 manufactured using the zigzag-type winding method is about twice as high as the maximum Q value of inductor section 14 manufactured using the U-type winding method. Therefore, it can be seen that the zigzag-type winding method is superior to the U-type winding method for the winding method of inductor section 14 that forms the resonant circuit of the stylus pen (10 in FIG. 4).

[0085] However, the maximum Q value of the inductor section 14 using the zigzag type 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 using the zigzag type winding method.

[0086] In one embodiment, the target Q value may be 200, the maximum Q value of the inductor unit 14 with the zigzag type winding scheme may be 100, and the maximum Q value of the inductor unit 14 with the U type winding scheme may be 50. In this case, since the magnitude of the magnetic signal resonated in the inductor unit 14 with the zigzag type winding scheme and the inductor unit 14 with the U type winding scheme is small, it may be difficult for the touch electrode layer (32 in FIG. 3) to receive the magnetic signal from the inductor unit 14 and to sense the touch position of the stylus pen (10 in FIG. 3) based on the received magnetic signal.

[0087] FIG. 20 is a diagram showing an N-step type winding method.

[0088] 20, the N-step type winding method may be a winding method that uses 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, in which the winding of the immediately upper layer region is wound after the winding of the lower layer region is finished, and the winding of the immediately upper layer region may start at the point where the winding of the lower layer region ends. However, the point where the winding of the lower layer region ends may be different from that of the U-type winding method.

[0089] For example, in the U-type winding method, the upper layer region is wound when the winding of the lower layer region is completed, while in the N-step type winding method, the lower layer region is divided into N parts, and the upper layer region can be wound when the winding of each of the divided N lower layers is completed. In this case, there may be multiple upper layers, and in such a case, the upper layers can be wound in sequence starting from the upper layer region closest to the lower layer region.

[0090] In addition, the N-step type winding method can minimize the voltage difference between adjacent windings by using a zigzag type winding method in which adjacent winding layers are alternately wound, although the alternately wound winding layers may be different from the zigzag type winding method.

[0091] For example, in a zigzag type winding scheme, all adjacent windings are wound alternately, while in an N step type winding scheme, among N divided winding stacks 201, 202, 203, and 204, windings may be wound from layer 3, region 10 of first winding stack 201 to layer 1, region 1 of second winding stack 202, from layer 3, region 10 of second winding stack 202 to layer 1, region 1 of third winding stack 203, and from layer 3, region 10 of third winding stack 203 to layer 1, region 1 of fourth winding stack 204.

[0092] The number of steps (N) of the N-step type winding scheme and the number of layers included in each of the winding stacks 201, 202, 203, and 204 may vary based on the Q value of the inductor. However, the number of steps (N) of the N-step type winding scheme may be a minimum of 3 or more, taking into account the target Q value. The description of the Q value of the N-step type winding scheme continues in detail in FIG. 22.

[0093] In addition, if there are too many steps in the N-step type winding method, the structure may become unstable, which may affect the deterioration of the Q value. Therefore, the number of steps (N) in the N-step type winding method may be a maximum of 10 or less.

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

[0095] 21, the inductor portion 210 includes a ferrite core 211 and may include four winding stacks 212-a, 212-b, 212-c, and 212-d that are wound around the ferrite core 211. In one embodiment, the four winding stacks 212-a, 212-b, 212-c, and 212-d may also be wound around a bobbin (17 in FIG. 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 may be a region where the 3rd layer 10th region of the first winding stack (201 in FIG. 20) and the 1st layer 1st region of the second winding stack (202 in FIG. 20) are connected, the second winding connection region 213-b may be a 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 FIG. 20) are connected, and the third winding connection region 213-c may be a 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 FIG. 20) are connected.

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

[0099] 22, a left region P01 of the ferrite core 220 of the inductor part (14 in FIG. 4) may be adjacent to the core body (11 in FIG. 4), and a right region P06 of the ferrite core 220 may be adjacent to the capacitor (13 in FIG. 4). A coil (16 in FIG. 4) may be wound on 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 part. Therefore, the current flowing through the coil 16 may not leak to the core body 11 or the capacitor 13.

[0100] The ferrite core 220 may be separated into a plurality of regions at regular intervals based on the axial direction of the ferrite core 220, and the coils may be wound individually in the plurality of regions. For example, the P02 region may be a first winding stack region in which a first winding stack (201 in FIG. 20) is wound around the ferrite core 220, the P03 region may be a second winding stack region in which a second winding stack (202 in FIG. 20) is wound around the ferrite core 220, the P04 region may be a third winding stack region in which a third winding stack (203 in FIG. 20) is wound around the ferrite core 220, and the P05 region may be a fourth winding stack region in which a fourth winding stack (204 in FIG. 20) is wound around the ferrite core 220.

[0101] FIG. 23 is a diagram showing the Q value according to the number of twist turns and the winding method.

[0102] 16, 20, and 23, sample 1 may be an inductor section (14 in FIG. 4) using a 15N Litz wire cable and an N-step type winding method, and sample 2 may be an inductor section 14 using a 0N Litz wire cable and a zigzag type winding method.

[0103] The Q value of sample 1 using a 15N Litz wire cable and an N-step type winding method may be 200. In contrast, the Q value of sample 2 using 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 the 15N twisted turns of the Litz wire cable and the N-step type winding method, may be greater than the Q value of sample 2, which is configured based on the 0 twisted turns of the Litz wire cable or the zigzag type winding method.

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

[0105] The higher the magnetic signal the touch electrode layer (32 in FIG. 3) receives from the stylus pen 10, the more accurately it can detect the position where the stylus pen 10 touches the touch screen (20b in FIG. 3). Also, the higher the magnetic signal the touch screen (20b in FIG. 3) receives from the stylus pen 10, the smaller the minimum voltage of the touch screen 20b for detecting the magnetic signal can be, so that the touch screen 20b can operate with lower power.

[0106] Therefore, compared to the stylus pen 10 including the inductor portion 14 of sample 2 (10 in FIG. 3), the stylus pen 10 including the inductor portion 14 of sample 1 enables the touch screen 20b to accurately sense the touch position of the stylus pen 10 and allows the touch screen 20b to operate with lower power.

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

Claims

1. Ferrite core, and A coil including a plurality of metal wires twisted together so that the number of twist turns per unit length is n or more, the coil being wound on the outer surface of the ferrite core. Including a stylus pen.

2. 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 to another point and then back to the one point. The stylus pen according to claim 1 .

3. The plurality of metal wires are The coil includes a central metal wire located at an inner center thereof and a plurality of outer metal wires located at an inner outer periphery thereof, The number of twist turns per unit length is the number of times that the outer metal wire is wound from the one point on the outer surface of the ferrite core to the other point and then back to the one point, The stylus pen according to claim 2.

4. The plurality of metal wires are The coil includes a plurality of central metal wires located at an inner center thereof and a plurality of outer metal wires located at an inner outer periphery thereof, The number of twist turns per unit length is the number of times that the outer metal wire is wound from the one point on the outer surface of the ferrite core to the other point and then back to the one point, The stylus pen according to claim 2.

5. The coil is The winding is spaced apart from both side ends of the ferrite core in the axial direction. The stylus pen according to claim 2.

6. The ferrite core is divided into a plurality of regions at regular intervals based on an axial direction of the ferrite core, and the coil is wound individually in the plurality of regions.

6. A stylus pen according to claim 5.

7. each of the plurality of regions includes a lower region and an upper region disposed above the lower region, and winding of the upper region begins when winding of the lower region ends; 7. A stylus pen according to claim 6.

8. the upper layer region includes a first upper layer region and a second upper layer region; the first upper region is disposed above the lower region; The second upper layer region is disposed above the first upper layer region.

8. A stylus pen according to claim 7.

9. The coil is Winding a bobbin surrounding at least a portion of the ferrite core; The stylus pen according to claim 7.

10. A stylus pen including an inductor portion including a Litz wire cable including a plurality of metal wires twisted in a rotational manner around a portion of a ferrite core, and a capacitor electrically connected to the inductor portion; and a touch screen including a touch electrode layer for receiving an electromagnetic signal resonated by the stylus pen; Touch system including.

11. The plurality of metal wires are The ferrite core is twisted in a rotating manner to a portion of the ferrite core at a distance from each of both side ends in the axial direction of the ferrite core. The touch system of claim 10.

12. The ferrite core is divided into a plurality of regions at regular intervals based on an axial direction of the ferrite core, The Litz wire cable is wound individually in the multiple regions. The touch system of claim 11.

13. each of the plurality of regions includes a lower region and an upper region disposed above the lower region, and winding of the upper region begins when winding of the lower region ends; The touch system of claim 12.

14. The Litz wire cable is wound around a first region, which is one of the plurality of regions, and a first connecting region that connects a second region adjacent to the first region. The touch system of claim 13.

15. The first connection region includes a connection region in which an upper layer region of the first region and a lower layer region of the second region are connected by the Litz wire cable. The touch system of claim 14.

16. The Litz wire cable is Winding a bobbin surrounding at least a portion of the ferrite core; The touch system of claim 15.

17. an inductor portion including a coil including a plurality of metal wires wound in multiple steps around a portion of a ferrite core and twisted in a rotational configuration; and a capacitor portion electrically connected to the coil; Touch system including.

18. The coil is wound in a plurality of steps on a portion of the ferrite core, The ferrite core is wound around a plurality of winding stack regions and a plurality of winding connection regions that connect the plurality of winding stack regions.

20. The touch system of claim 17.

19. The plurality of winding stack regions include: a region in which the ferrite core is separated into a plurality of regions at a distance from each of both side ends in an axial direction of the ferrite core, each of the plurality of regions including a plurality of layers in which the coil is wound; 20. The touch system of claim 18.

20. The plurality of winding coupling regions include a first winding stack region, which is any one of the plurality of winding stack regions, and a second winding stack region adjacent to the first winding stack region; and a first layer, which is the highest layer of the plurality of layers included in the first winding stack region, and a second layer, which is the lowest layer of the plurality of layers included in the second winding stack region.

20. The touch system of claim 19.

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