Abstract:
The present invention relates to a meta-material structure and, more specifically, to a meta-material structure that refracts an electromagnetic field. According to one aspect of the present invention, a meta-material structure refracting a magnetic field of a particular frequency can be provided, wherein the meta-material structure comprises: a substrate; a first conductor line disposed on one surface of the substrate; a second conductor line disposed on the other surface of the substrate; and two connecting members for connecting both ends of the first conductor line and the second conductor line penetrating the substrate. When looked at from the top, both ends of the first conductor line and the second conductor line of the provided meta-material structure are located in the same place, and the first conductor line and the second conductor line form a twisted shaped path.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention relates to a metamaterial structure, and more particularly, to a metamaterial structure that refracts an electromagnetic field. 
         [0003]    2. Discussion of the Related Art 
         [0004]    A wireless power transmission technology is a technology that wirelessly transmits power between a power source and an electronic apparatus. As one example, the wireless power transmission technology can wirelessly charge a battery of a mobile terminal just by putting a mobile terminal such as a smart phone or a tablet on a wireless charging pad to provide higher mobility, convenience, and safety than a wired charging environment using the existing wired charging connector. Further, the wireless power transmission technology attracts public attention to substitute the existing wired power transmission environment in various fields such as medical treatment, leisure, a robot, and the like, which include home appliances and an electric vehicle afterwards in addition to wireless charging of the mobile terminal. 
         [0005]    The wireless power transmission technology may be classified into a technology using electromagnetic wave radiation and a technology using an electromagnetic induction phenomenon, and since the technology using the electromagnetic wave radiation has a limit of efficiency depending on radiation loss consumed in the air, the technology using the electromagnetic induction phenomenon has been primarily researched in recent years. 
         [0006]    The wireless power transmission technology using the electromagnetic induction phenomenon is generally classified into an electromagnetic inductive coupling scheme and a resonant magnetic coupling scheme. 
         [0007]    The electromagnetic inductive coupling scheme is a scheme that transmits energy by using current induced to a coil at a receiving side due to a magnetic field generated at a coil at a transmitting side according to electromagnetic coupling between the coil at the transmitting side and the coil at the receiving side. The wireless power transmission technology of the electromagnetic inductive coupling scheme has an advantage that transmission efficiency is high, but has a disadvantage that a power transmission distance is limited to several mms and is very sensitive to matching of the coils, and as a result, a degree of positional freedom is remarkably low. 
         [0008]    The resonant magnetic coupling scheme as a technology proposed by Professor Marine Solarbeach of MIT in 2005 is a scheme that transmits energy by using a phenomenon in which the magnetic field focused on both sides of the transmitting side and the receiving side by the magnetic field applied at a resonance frequency between the coil at the transmitting side and the coil at the receiving side. As a result, the resonant magnetic coupling scheme is expected as the wireless power transmission technology that can transmit energy up to a comparatively long distance from several cms to several ms as compared with the magnetic inductive coupling scheme to implement authentic cord-free. 
         [0009]    A metamaterial proposed by Professor Pendry in UK in 1999 as a material constituted by periodic arrays having a specific pattern generally means a material having a material property which cannot exist in nature. The metamaterial has a positive or negative refraction index with respect to the electromagnetic field as a primary characteristic and it is predicted that when the metamaterial is used, the electromagnetic field as a near field can be focused to improve coverage of wireless power transmission. 
       SUMMARY OF THE INVENTION 
       [0010]    An object of the present invention is to provide a metamaterial structure having a refraction index of ‘0’ or a negative refraction index with respect to an electromagnetic field having a specific frequency. 
         [0011]    Effects of the present invention are not limited to the aforementioned effects and unmentioned effects will be clearly understood by those skilled in the art from the specification and the appended claims. 
         [0012]    In accordance with an embodiment of the present invention, a metamaterial structure refracting a magnetic field having a specific frequency, includes: a substrate; a first conductor line deployed on one surface of the substrate; a second conductor line deployed on the other surface of the substrate; and two connection members connecting both ends of the first conductor line and the second conductor line through the substrate, wherein the first conductor line and the second conductor line have both ends positioned at the same location and are provided to form twisted paths. 
         [0013]    Objects to be solved by the present invention are not limited to the aforementioned objects and unmentioned objects will be clearly understood by those skilled in the art from the specification and the appended claims. 
         [0014]    According to the present invention, an electromagnetic field can be focused by using a metamaterial structure having a refraction index of ‘0’ or a negative refraction index with respect to a specific frequency and this is applied to a wireless power transmission technology to improve coverage of wireless power transmission. 
         [0015]    Objects to be solved by the present invention are not limited to the aforementioned objects and unmentioned objects will be clearly understood by those skilled in the art from the specification and the appended claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a graph regarding an effective dielectric constant and effective permeability for each frequency of a magnetic field lens according to an embodiment of the present invention; 
           [0017]      FIG. 2  is a block diagram of a wireless power transmitting system according to an embodiment of the present invention; 
           [0018]      FIG. 3  is a block diagram of a wireless power transmitting apparatus according to the embodiment of the present invention; 
           [0019]      FIG. 4  is a block diagram of a wireless power receiving apparatus according to the embodiment of the present invention; 
           [0020]      FIG. 5  is a diagram illustrating magnetic field focusing of a metamaterial structure according to the embodiment of the present invention; 
           [0021]      FIGS. 6 to 9  are diagrams regarding a metamaterial structure  1000  according to the embodiments of the present invention; 
           [0022]      FIG. 6  is a plan view of a first form of the metamaterial structure according to the embodiment of the present invention; 
           [0023]      FIG. 7  is a bottom view of the first form of the metamaterial structure according to the embodiment of the present invention; 
           [0024]      FIG. 8  is a cross-sectional view of region A of  FIG. 6 ; 
           [0025]      FIG. 9  is a cross-sectional view of region B of  FIG. 6 ; 
           [0026]      FIG. 10  is a graph regarding a refraction index of the first form of the metamaterial structure according to the embodiment of the present invention; 
           [0027]      FIG. 11  is a diagram regarding a second form of the metamaterial structure according to the embodiment of the present invention; 
           [0028]      FIG. 12  is a diagram regarding a third form of the metamaterial structure according to the embodiment of the present invention; 
           [0029]      FIG. 13  is a diagram regarding a fourth form of the metamaterial structure according to the embodiment of the present invention; 
           [0030]      FIG. 14  is a diagram regarding a fifth form of the metamaterial structure according to the embodiment of the present invention; 
           [0031]      FIG. 15  is a diagram regarding a sixth form of the metamaterial structure according to the embodiment of the present invention; 
           [0032]      FIG. 16  is a diagram regarding a seventh form of the metamaterial structure according to the embodiment of the present invention; and 
           [0033]      FIG. 17  is a diagram regarding an eighth form of the metamaterial structure according to the embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0034]    Since embodiments disclosed in the specification are used to clearly describe the spirit of the present invention for those skilled in the art, the present invention is not limited to the exemplary embodiments disclosed in the specification and it should be analyzed that the scope of the present invention includes a modified example and a transformed example without departing from the spirit of the present invention. 
         [0035]    Terms and the accompanying drawings used in the specification are used to easily describe the present invention and shapes illustrated in the drawings may be enlarged as necessary for help understanding the present invention, and as a result, the present invention is not limited by the terms and the drawings used in the specification. In describing the present invention, when it is determined that the detailed description of the known configuration or function related to the present invention may obscure the gist of the present invention, the detailed description thereof will be omitted. 
         [0036]    In accordance with an embodiment of the present invention, a metamaterial structure refracting a magnetic field having a specific frequency, includes: a substrate; a first conductor line deployed on one surface of the substrate; a second conductor line deployed on the other surface of the substrate; and two connection members connecting both ends of the first conductor line and the second conductor line through the substrate, wherein the first conductor line and the second conductor line have both ends positioned at the same location and are provided to form twisted paths. 
         [0037]    The first conductor line and the second conductor line may be provided to form having an ‘8’ shape, a twisted ribbon shape, or an unlimited symbol shape from the top view. 
         [0038]    Further, the first conductor line and the second conductor line may be provided in such a manner that a path formed by the first conductor line and a path formed by the second conductor line cross each other. 
         [0039]    The first conductor line and the second conductor line may be provided to form paths symmetric to each other based on a location where the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view. 
         [0040]    At least one gap serving as an air capacitor may be formed on the paths formed by the first conductor line and the second conductor line. 
         [0041]    The first conductor line and the second conductor line may be provided in such a manner that the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view, the first conductor line and the second conductor line may be provided to form paths symmetric to each other based on a location where the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view, and the at least one gap may be provided at the locations symmetric to each other based on the location where the first conductor line and the second conductor line cross each other or provided at the location where the first conductor line and the second conductor line cross each other. 
         [0042]    The metamaterial structure may further include at least one capacitor inserted on the paths formed by the first conductor line and the second conductor line. 
         [0043]    The first conductor line and the second conductor line may be provided in such a manner that the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view, the first conductor line and the second conductor line may be provided to form paths symmetric to each other based on a location where the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view, and the at least one capacitor may be provided at the locations symmetric to each other based on the location where the first conductor line and the second conductor line cross each other or provided at the location where the first conductor line and the second conductor line cross each other. 
         [0044]    At least one of the first conductor line and the second conductor line may include a pattern line provided onto the formed by the first conductor line and the second conductor line in zigzags. 
         [0045]    The first conductor line and the second conductor line may be provided in such a manner that the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view, the first conductor line and the second conductor line may be provided to form paths symmetric to each other based on a location where the path formed by the first conductor line and the path formed by the second conductor line cross each other from the top view, and the at least one patter line may be provided at the locations symmetric to each other based on the location where the first conductor line and the second conductor line cross each other or provided at the location where the first conductor line and the second conductor line cross each other. 
         [0046]    Hereinafter, a metamaterial structure  1000  according to an embodiment of the present invention will be described. 
         [0047]    A metamaterial means an artificial material designed to have a characteristic which cannot be found in general nature. A representative example among characteristics of the metamaterial may include a refraction index of ‘0’ or a negative refraction index with respect to an electromagnetic field. 
         [0048]    The metamaterial may be prepared by primarily forming a specific pattern with a material such as metal or plastic and a characteristic material property of the metamaterial is given by not the material but the specific pattern. A representative example of the metamaterial may include a negative index material (NIM) having a negative value in both dielectric constant and permeability or single negative (SNG) having the negative value in only one of the dielectric constant and the permeability and may have such a property by patterning of a split ring resonator (SRR), and the like. 
         [0049]    The metamaterial structure  1000  means a structure provided to have the characteristic of the metamaterial. 
         [0050]    The metamaterial structure  1000  according to the embodiment of the present invention may focus the electromagnetic field. 
         [0051]    The metamaterial structure  1000  may have the refraction index of ‘0’ (zero refraction index) or the negative refraction index (minus refraction index) as the refraction index for the electromagnetic field having the specific frequency. When a magnetic field passes through the metamaterial structure  1000  having the refraction index of ‘0’ or the negative refraction index, a similar effect to a case in which light passing through an optical lens is refracted is shown. That is, the metamaterial structure  1000  may focus the electromagnetic field which spreads radially in a desired direction. 
         [0052]    When such an effect is used, the magnetic field which radially spreads from a wireless power transmitting apparatus  2100  may be refracted and focused in a vertical direction to the metamaterial structure  1000  or focused toward a wireless power receiving apparatus  2200  by using the metamaterial structure  1000 . 
         [0053]    Therefore, when the metamaterial structure  1000  is used, a rate at which the magnetic field radiated from the wireless power transmitting apparatus  2100  is radiated to an undesired atmosphere decreases, and as a result, radiation efficiency of the magnetic field transferred from the wireless power receiving apparatus  2200  from the wireless power transmitting apparatus  2100  increases, consequently, transmission efficient and a transmission distance may be improved while the wireless power transmission using the magnetic field. 
         [0054]    A principle in which the metamaterial structure  1000  has the refraction index of ‘0’ or the negative refraction index with respect to the electromagnetic field will be described below. 
         [0055]    A refraction index n for the electromagnetic field has the following functional relationship with respect to an effective dielectric constant eeff and effective permeability ueff. 
         [0000]    
       
      
       n=eeff×ueff  
      
     
         [0056]    Therefore, when the effective dielectric constant or effective permeability of the metamaterial structure  1000  is adjusted to ‘0’, the metamaterial structure  1000  has the refraction index ‘0’. Similarly, when any one of the effective dielectric constant and the effective permeability of the metamaterial structure  1000  is adjusted to have the negative value, the metamaterial structure  1000  may have negative permeability. Herein, the effective dielectric constant eeff and the effective permeability ueff may adjust the size, the shape, and an interval of a specific pattern, the number of pattern repetition times, inductance, capacitance, and the like constituting the metamaterial structure  1000 . Therefore, the metamaterial structure  1000  having the refraction index of ‘0’ may be provided by adjusting the size, the shape, and the interval of the specific pattern, the number of pattern repetition times, the inductance, the capacitance, and the like constituting the metamaterial structure  1000  so that any one of the effective dielectric constant eeff and the effective permeability ueff becomes ‘0’. 
         [0057]    Similarly, the metamaterial structure  1000  having the negative refraction index may be provided by adjusting the size, the shape, and the interval of the specific pattern, the number of pattern repetition times, the inductance, the capacitance, and the like constituting the metamaterial structure  1000  so that any one of the effective dielectric constant eeff and the effective permeability ueff becomes the negative value. 
         [0058]    Meanwhile, since the effective dielectric constant eeff or the effective permeability ueff of the metamaterial structure  1000  varies differently for each frequency band, even though the effective dielectric constant eeff or the effective permeability ueff has the refraction index of ‘0’ or the negative refraction index with respect to a desired specific frequency, it should be noted that the effective dielectric constant eeff or the effective permeability ueff may not have the refraction index of ‘0’ or the negative refraction index with respect to other frequency bands. 
         [0059]      FIG. 1  is a graph regarding an effective dielectric constant and effective permeability for each frequency of a metamaterial structure  1000  according to an embodiment of the present invention. 
         [0060]    Referring to  FIG. 1  the metamaterial structure  1000  may have an effective permeability value of ‘0’ in approximately 13.6 Mhz. Therefore, the metamaterial structure  1000  has a refraction index of ‘0’ in the band of 13.6 MHz. Similarly, the metamaterial structure  1000  may have a negative effective permeability value in approximately 13.4 to 13.6 Mhz. Therefore, the metamaterial structure  1000  has a negative refraction index in the corresponding range. 
         [0061]    When the metamaterial structure  1000  having the refraction index of ‘0’ or the negative refraction index is used in the wireless power transmitting system  2000 , power transmission efficiency may increase by improving radiation efficiency while wireless power transmission. 
         [0062]    Hereinafter, a wireless power transmitting system  2000  according to an embodiment of the present invention will be described. 
         [0063]      FIG. 2  is a block diagram of a wireless power transmitting system  2000  according to an embodiment of the present invention. 
         [0064]    Referring to  FIG. 2 , the wireless power transmitting system  2000  includes a wireless power transmitting apparatus  2100  and a wireless power receiving apparatus  2200 . The wireless power transmitting apparatus  2100  receives power from an external power source S to generate the magnetic field. The wireless power transmitting apparatus  2200  generates current by using the generated magnetic field to receive power wirelessly. 
         [0065]    Herein, the wireless power transmitting apparatus  2100  may be provided as a fixed type or a movable type. An example of the fixed type includes a type which is embedded in a ceiling or a wall surface or a furniture such as a table, or the like indoor, a type which is installed in an outdoor parking lot, a bus stop, or a subway station as an implant type, or a type which is installed in transporting means such as a vehicle or a train. The movable wireless power transmitting apparatus  2100  may be implemented as a part of a movable apparatus having a movable weight or size or other apparatus such as a cover of a notebook computer, or the like. 
         [0066]    Further, the wireless power transmitting apparatus  2200  should be analyzed as a comprehensive concept including various electronic apparatuses including a battery and various home appliances driven by receiving power wirelessly instead of a power cable. Representative examples of the wireless power transmitting apparatus  2200  include a portable terminal, a cellular phone, a smart phone, a personal digital assistant (PDA), a portable media player (PMP), a WiBro terminal, a tablet, a pablet, a notebook, a digital camera, a navigation terminal, a television, an electric vehicle (EV), and the like. 
         [0067]    One or more wireless power transmitting apparatuses  2200  may be present in the wireless power transmitting system  2000 . In  FIG. 2 , it is expressed that the wireless power transmitting apparatus  2100  and the wireless power receiving apparatus  2200  transmit and receive power one to one, but one wireless power transmitting apparatus  2100  may transmit power to the plurality of wireless power receiving apparatuses  2200 . In particular, when the wireless power transmission is performed in the resonant magnetic coupling scheme, one wireless power transmitting apparatus  2100  may transmit power to a plurality of wireless power receiving apparatuses  2200  simultaneously by applying a simultaneous transmission scheme or a time division transmission scheme. 
         [0068]    Meanwhile, although not illustrated in  FIG. 2 , the wireless power transmitting system  2000  may further include a relay for increasing a power transmission distance. As the relay, a passive type resonance loop implemented by an LC circuit may be used. The resonance loop may increase the wireless power transmission distance by focusing a magnetic field radiated to the atmosphere. It is possible to secure wider wireless power transmission coverage by simultaneously using a plurality of relays. 
         [0069]    Hereinafter, the wireless power transmitting apparatus  2100  according to the embodiment of the present invention will be described. 
         [0070]    The wireless power transmitting apparatus  2100  may transmit power wirelessly. 
         [0071]      FIG. 3  is a block diagram of the wireless power receiving apparatus  2100  according to the embodiment of the present invention. 
         [0072]    Referring to  FIG. 3 , the wireless power transmitting apparatus  2100  may include an AC-DC converter  2110 , a frequency oscillator  2120 , a power amplifier  2130 , an impedance matcher  2140 , and a transmitting antenna  2150 . 
         [0073]    The AC-DC converter  2110  may convert AC power into DC power. The AC-DC converter  2110  receives the AC power from the external power source S and converts a wavelength of the received AC power into the DC power and outputs the DC power. The AC-DC converter  2110  may adjust a voltage value of the output DC power. 
         [0074]    The frequency oscillator  2120  may convert the DC power into AC power having a desired specific frequency. The frequency oscillator  2120  receives the DC power output by the AC-DC converter  2110  and converts the received DC power into AC power having a specific frequency and outputs the AC power. Herein, the specific frequency may be a resonance frequency. In this case, the frequency oscillator  2120  may output the AC power having the resonance frequency. 
         [0075]    The power amplifier  2130  may amplify voltage or current of power. The power amplifier  2130  receives the AC power having the specific frequency, which is output by the frequency oscillator  2120 , and amplifies voltage or current of the received AC power having the specific frequency and outputs the amplified voltage or current. 
         [0076]    The impedance matcher  2140  may perform impedance matching. The impedance matcher  2140  may include a capacitor, an inductor, and a switching element that switches a connection thereof. Impedance matching may be performed by detecting a reflection wave of the wireless power transmitted through the receiving antenna  2150 , adjusting a connection state of the capacitor or the inductor by switching the switching element based on the detected reflection wave, or adjusting capacitance of the capacitor or inductance of the inductor. 
         [0077]    The transmitting antenna  2150  may general an electromagnetic field by using the AC power. The transmitting antenna  2150  receives the AC power having the specific frequency, which is output by the amplifier  2130  to thereby generate a magnetic field having a specific frequency. The generated magnetic field is radiated and the wireless power transmitting apparatus  2200  receives the radiated magnetic field to generate current. In other words, the transmitting antenna  2150  wirelessly transmits power. 
         [0078]    Hereinafter, the wireless power transmitting apparatus  2200  according to the embodiment of the present invention will be described. 
         [0079]    The wireless power transmitting apparatus  2200  may receive power wirelessly. 
         [0080]      FIG. 4  is a block diagram of the wireless power receiving apparatus  2200  according to the embodiment of the present invention. 
         [0081]    Referring to  FIG. 4 , the wireless power transmitting apparatus  2200  may include a receiving antenna  2210 , an impedance matcher  2220 , a rectifier  2230 , a DC-DC converter  2240 , and a battery  2250 . 
         [0082]    The receiving antenna  2210  may receive the wireless power transmitted by the wireless power transmitting apparatus  2100 . The receiving antenna  2210  may receive power by using the magnetic field radiated by the transmitting antenna  2150 . Herein, when a specific frequency is the resonance frequency, a magnetic resonance phenomenon occurs between the transmitting antenna  2150  and the receiving antenna  2210 , and as a result, power may be more efficiently received. 
         [0083]    The impedance matcher  2220  may adjust impedance of the wireless power transmitting apparatus  2200 . The impedance matcher  2220  may include a capacitor, an inductor, and a switching element that switches a connection thereof. The impedance may be matched by controlling a switching element of a circuit constituting the impedance matcher  2220  based on a voltage value or a current value, a power value, a frequency value, and the like of the received wires power. 
         [0084]    The rectifier  2230  rectifies the received wireless power to convert AC power to DC power. The rectifier  2230  may convert the AC power into the DC power by using a diode or a transistor and smooth the DC power by using the capacitor or a resistor. As the rectifier  2230 , a full-wave rectifier, a half-wave rectifier, a voltage multiplier, and the like implemented by a bridge circuit, and the like may be used. 
         [0085]    The DC-DC converter  2240  converts voltage of the rectified DC power into a desired level to output the voltage having the desired level. When a voltage value of the DC power rectified by the rectifier  2230  is larger or smaller than a voltage value required to charge the battery or drive the electronic apparatus, the DC-DC converter  2240  may change the voltage value of the rectified DC power to desired voltage. 
         [0086]    The battery  2250  may store energy by using the power output from the DC-DC converter  2240 . Meanwhile, the wireless power transmitting apparatus  2200  needs not particularly include the battery  2250 . For example, the battery may be provided as an external component which is detachable. As another example, the wireless power transmitting apparatus  2200  may include driving means that drives various operations of the electronic apparatus instead of the battery  2250 . 
         [0087]    Hereinafter, a process in which the power is wirelessly transmitted in the wireless power transmitting system  2000  according an embodiment of the present invention will be described. 
         [0088]    Wireless transmission of the power may be performed by using the electromagnetic inductive coupling scheme or the resonant magnetic coupling scheme. In this case, the wireless transmission of the power may be performed between the transmitting antenna  2150  of the wireless power transmitting apparatus  2100  and the receiving antenna  2210  of the wireless power receiving apparatus  2200 . 
         [0089]    When the resonant magnetic coupling scheme is used, each of the transmitting antenna  2150  and the receiving antenna  2210  may be provided in a form of a resonance antenna. The resonance antenna may have a resonance structure including the coil and the capacitor. In this case, the resonance frequency of the resonance antenna is determined by the inductance of the coil and the capacitance of the capacitor. Herein, the coil may be formed in a form of a loop. Further, a core may be placed in the loop. The core may include a physical core such as a ferrite core or an air core. 
         [0090]    Energy transmission between the transmitting antenna  2150  and the receiving antenna  2210  may be performed through a resonance phenomenon of the magnetic field. The resonance phenomenon means a phenomenon in which both resonance antennas are coupled to each other, and as a result, energy is transferred between the resonance antennas with high efficiency in the case where other resonance antennas are positioned around one resonance antenna when a near field corresponding to the resonance frequency is generated in one resonance antenna. When the magnetic field corresponding to the resonance frequency is generated between the resonance antenna of the transmitting antenna  2150  and the resonance antenna of the receiving antenna  2210 , the resonance phenomenon occurs, in which the resonance antennas of the transmitting antenna  2150  and the receiving antenna  2210 , and as a result, in a general case, the magnetic field is focused toward the receiving antenna  2210  with higher efficiency than a case in which the magnetic field generated in the transmitting antenna  2150  is radiated to free space. Therefore, energy may be transferred from the transmitting antenna  2150  to the receiving antenna  2210  with high efficiency. 
         [0091]    The electromagnetic inductive coupling scheme may be implemented similarly to the resonance magnetic coupling scheme, but in this case, the frequency of the magnetic field need not be the resonance frequency. Instead, in the electromagnetic inductive coupling scheme, matching the loops constituting the receiving antenna  2210  and the transmitting antenna  2150  is required and a gap between the loops needs to be very small. 
         [0092]    Hereinafter, a process in which the power is wirelessly transmitted in the wireless power transmitting system  1000  according an embodiment of the present invention will be described. 
         [0093]    When the power transmission is wirelessly performed by using the magnetic resonance as described above, the magnetic field which is a near field generated from the transmitting antenna  2150  spreads radially, and as a result, when a distance between the transmitting antenna  2150  and the receiving antenna  2210  increases, power transmission efficiency may deteriorate. The metamaterial structure  1000  may focus the magnetic field which spreads radially between the transmitting antenna  2150  and the receiving antenna  2210  to be radiated in a desired direction. 
         [0094]      FIG. 5  is a diagram illustrating magnetic field focusing of a metamaterial structure  1000  according to the embodiment of the present invention. 
         [0095]    Referring to  FIG. 5 , the wireless power transmitting apparatus  2100  radiates the magnetic field through the transmitting antenna  2150 . The magnetic field spreads radially from the loop of the transmitting antenna  2150 . 
         [0096]    The metamaterial structure  1000  may be deployed between the transmitting antenna  2150  and the receiving antenna  2210 . The metamaterial structure  1000  has the refraction index of ‘0’ or the negative refraction index with respect to the frequency of the radiated magnetic field. 
         [0097]    For example, the metamaterial structure  1000  having the characteristic of  FIG. 1  has the effective permeability of ‘0’ with respect to the magnetic field having the frequency in the band of 13.6 Mhz to have the refraction index of ‘0’. Further, the metamaterial structure  1000  has the negative effective permeability and the positive effective dielectric constant with respect the magnetic field in the frequency band of 13.4 to 13.6 Mhz to have the negative refraction index. 
         [0098]    The metamaterial structure  1000  refracts the magnetic field which spreads radially from the transmitting antenna  2150  toward the receiving apparatus  2210 . As a result, the metamaterial structure  1000  radiates a magnetic field MFair radiated to the atmosphere toward the receiving antenna  2210  when the metamaterial structure  1000  does not exist to transfer more magnetic fields from the transmitting antenna  2150  to the receiving antenna  2210 . As a result, the power transmission efficiency may be improved while the wireless power transmission. 
         [0099]    Hereinafter, a structure of the metamaterial structure  1000  according to the embodiment of the present invention will be described in detail. 
         [0100]      FIGS. 6 to 9  are diagrams regarding the metamaterial structure  1000  according to the embodiment of the present invention, and  FIG. 6  is a plan view of a first form of the metamaterial structure  1000  according to the embodiment of the present invention,  FIG. 7  is a bottom view of the first form of the metamaterial structure according to the embodiment of the present invention,  FIG. 8  is a cross-sectional view of region A of  FIG. 6 , and  FIG. 9  is a cross-sectional view of region B of  FIG. 6 . 
         [0101]    Referring to  FIGS. 6 to 9 , the metamaterial structure  1000  may include a substrate  1100 , a first conductor line  1200 , a second conductor line  1300 , a connection member  1400 , and a capacitor  1500 . 
         [0102]    The substrate  1100  may be provided in a flat form. The substrate  1100  may be provided in such a manner that one surface of the substrate  1100  and the other surface which is an opposite surface thereto are parallel to each other. Further, the substrate  1100  may be made of a material that does not shield the magnetic field. For example, the substrate  1100  may be made of CER-10 or a material similar thereto. 
         [0103]    Referring to  FIG. 6  or  7 , the first conductor line  1200  may be provided on one surface of the substrate  1100 . For example, the first conductor line  1200  may be provided so as to be attached onto one surface of the substrate  1100 . Alternatively, the first conductor line  1200  may be provided so as to be patterned with embossing or intaglio on one surface of the substrate  1100 . 
         [0104]    Referring to  FIG. 6  or  7 , the second conductor line  1300  may be provided on the other surface of the substrate  1100 . The second conductor line  1300  may be provided on the substrate  1100  in the similar manner to the first conductor line  1200 . For example, the second conductor line  1300  may be provided so as to be attached onto the other surface of the substrate  1100 . Alternatively, the second conductor line  1300  may be provided so as to be patterned with embossing or intaglio on the other surface of the substrate  1100 . 
         [0105]    The first conductor line  1200  and the second conductor line  1300  may be deployed with both ends thereof positioned at the same locations from the top view. For example, the first conductor line  1200  and the second conductor line  1300  may be deployed with both ends thereof positioned at region A of  FIG. 6  and region B of  FIG. 6 . 
         [0106]    The connection member  1400  may connect the first conductor line  1200  and the second conductor line  1300 . Referring to  FIGS. 6 and 7 , the connection member  1400  may be deployed at locations where both ends of the first conductor line  1200  and both ends of the second conductor line  1300  meet from the top view. For example, one connection member  1400  may be provided at each of regions A and B of  FIG. 6 . The connection member  1400  may extend from the first conductor line  1200  toward the second conductor line  1300  by passing through the substrate  1100  at the locations where both ends of the first conductor line  1200  and the second conductor line  1300  meet. For example, as illustrated in  FIG. 9 , the connection member  1400  may connect one end of the first conductor line  1200  and one end of the second conductor line  1300  through the substrate  1100  at region A. The connection member  1400  may connect the other end of the first conductor line  1200  and the other end of the second conductor line  1300  through the substrate  1100  at region B. As a result, the first conductor line  1200  and the second conductor line  1300  may be electrically connected with each other. 
         [0107]    Herein, the first conductor line  1200  and the second conductor line  1300  may be deployed along a path forming a specific pattern from the top view. Referring to  FIGS. 6 and 7 , the first conductor line  1200  and the second conductor line  1300  may be provided to form a path having a twisted from the top view. For example, the first conductor line  1200  and the second conductor line  1300  may be provided to form a path having an ‘8’ shape, a twisted ribbon shape, or an unlimited symbol (‘∞’) shape from the top view. 
         [0108]    Referring to  FIGS. 6 and 7 , the first conductor line  1200  may include both line portions  1201  and  1202  separated from and parallel to each other, a first diagonal line portion  1205  connected from any one upper end  1201  of both line portions  1201  and  1202  to the other one lower end  1202 , a second diagonal line portion  1203  which extends from any one lower end  1201  of both line portion  1201  and  1202  up to region A toward the other one upper end  1202 , and a third diagonal line portion  1204  which extends from the upper end of the other one both-side line portion  1202  up to region B toward the lower end of any one both-side line portion  1201 . 
         [0109]    Herein, the second diagonal line portion  1203  extends from region A to be connected to the lower end of any one both-side line portion  1201  and any one  1201  of the both-side line portion is connected to the first diagonal line portion  1205  at an upper end thereof again and the first diagonal line portion  1205  is connected to the lower end of the other one  1202  of the both-side line portion again and the other both-side line portion  1202  is connected to the third diagonal line portion  1204  at an upper end thereof, and the third diagonal line portion  1204  extends up to region A from the upper end of the other both-side line portion  1202 . As a result, both line portions  1201  and  1202 , the first diagonal line portion  1205 , the second diagonal line portion  1203 , and the third diagonal line portion  1204  may be provided to form one path from one end of region A up to the other end of region B. 
         [0110]    Referring back to  FIGS. 6 and 7 , the second conductor line  1300  may extend from region A toward region B. Herein, one end of the second conductor line  1300  is connected with one end of the first conductor line  1200  by a connection member  1400   a  at region A as illustrated in  FIG. 8 . Further, the other end of the second conductor line  1300  is connected with the other end of the first conductor line  1200  by a connection member  1400   b  at region B as illustrated in  FIG. 9 . 
         [0111]    As a result, the first conductor line  1200  and the second conductor line  1300  may be generally connected to each other and provided to form the path having the ‘8’ shape, the twisted ribbon shape, or the unlimited symbol (‘∞’) shape from the top view. 
         [0112]    However, herein, the shapes of the first conductor line  1200  and the second conductor line  1300  are not particularly limited to the aforementioned example. 
         [0113]    For example, the first conductor line  1200  may be constituted only by both line portions  1201  and  1202  parallel to each other and the first diagonal line portion  1205  and the second conductor line  1300  may extend from the lower end of any one  1201  of both line portions up to the upper end of the other one  1202 . Of course, in this case, the connection member  1400  may connect the first conductor line  1200  and the second conductor line  1300  at the lower end of any one  1201  of both line portions and connect the first conductor line  1200  and the second conductor line  1300  at the upper end of the other one  1202  of both line portions. Even in this case, the first conductor line  1200  and the second conductor line  1300  may be generally connected to each other and provided to form the path having the ‘8’ shape, the twisted ribbon shape, or the unlimited symbol (‘∞’) shape from the top view. 
         [0114]    As the other example, the first conductor line  1200  may be constituted only by any one  1201  of both line portions and the first diagonal line portion  1205  and the second conductor line  1300  may include a line deployed at the position of the other one  1202  of both line portions from the top view and a diagonal line portion deployed at a position connected from the other end of any one  1201  to the upper end of the other one  1202  from the top view. Even in this case, the first conductor line  1200  and the second conductor line  1300  may be generally connected to each other and provided to form the path having the ‘8’ shape, the twisted ribbon shape, or the unlimited symbol (‘∞’) shape from the top view. 
         [0115]    In other words, the first conductor line  1200  and the second conductor line  1300  are deployed on opposite surfaces of the substrate  1100  to each other, both ends are connected by the connection member  1400  at the same location and deployed to form the path having the ‘8’ shape, the twisted ribbon shape, or the unlimited symbol (‘∞’) shape from the top view and herein, a location connecting the first conductor line  1200  and the second conductor line  1300  may be arbitrarily selected from any two locations on the path. 
         [0116]    The capacitor  1500  may be provided to be inserted into any one of the first conductor line  1200  and the second conductor line  1300  on the path formed by the first conductor line  1200  and the second conductor line  1300 . One or multiple capacitors  1500  may be provided. 
         [0117]    For example, referring to  FIGS. 6 and 7 , the capacitor  1500  may include capacitors  1500   a  and  1500   b  inserted into each of both line portions  1201  and  1202  of the first conductor line  1200 , respectively, a capacitor  1500   c  inserted into the first diagonal line portion  1205  of the first conductor line  1200 , and a capacitor  1500   d  inserted into the second conductor line  1300 . 
         [0118]    The metamaterial structure  1000  having the aforementioned structure may have the refraction index of ‘0’ or the negative refraction index with respect to the electromagnetic field. 
         [0119]      FIG. 10  is a graph regarding a refractive index of the first form of the metamaterial structure according to the embodiment of the present invention. 
         [0120]    Referring to  FIG. 10 , an equivalent circuit of the metamaterial structure  1000  needs to be provided to have a value of ‘0’ or a negative 0 value in order to have the refraction index of ‘0’ or the negative refraction index with respect to the magnetic field. 
         [0121]    To this end, the metamaterial structure  1000  needs to be provided in a purely left-handed (PLH) structure. That is, the equivalent circuit of the metamaterial structure  1000  needs to be configured to have serial capacitance and parallel capacitance. 
         [0122]    In the metamaterial structure  1000  having the structure described in  FIGS. 6  to  9 , the serial capacitance may be generated by the capacitor  1500  inserted into the first conductor line  1200  or the second conductor line  1300 . Further, the parallel inductance may be generated at a portion where the first conductor line  1200  and the second conductor line  1300  are connected by the connection member  1400 . As a result, the metamaterial structure  1000  provided in the structure of  FIGS. 6 to 9  forms the PLH structure to have the refraction index of ‘0’ or the negative refraction index with respect to the electromagnetic field. 
         [0123]    Meanwhile, herein, the first conductor line  1200  and the second conductor line  1300  may be provided in such a manner that the paths formed by the first conductor line  1200  and the second conductor line  1300  are generally symmetric to each other from the top view. Further, when a plurality of capacitors  1500  is provided, the capacitors  1500  may be deployed at positions symmetric to each other based on a center of the paths formed by the first conductor line  1200  and the second conductor line  1300 . For example, the capacitors  1500  may be deployed at portions where the first conductor line  1200  and the second conductor line  1300  overlap with each other or provided at positions line-symmetric or point-symmetric based on the overlapped portion as a pair from the top view. 
         [0124]    Like this, when the paths formed by the first conductor line  1200  and the second conductor line  1300  have a symmetric structure, the resulting generated inductance forms a balance and further, when the capacitors  1500  are symmetrically deployed, the resulting generated capacitance forms the balance, and as a result, the electromagnetic field is stably refracted in overall, thereby more stably focusing the electromagnetic field. 
         [0125]    Hereinafter, various modified examples having a form provided by the metamaterial structure  1000  according to the embodiment of the present invention will be described. 
         [0126]    In the first form of the metamaterial structure  1000  of  FIGS. 6 to 9 , it is described that each of the capacitors  1500   a ,  1500   b ,  1500   c , and  1500   d  is deployed at both line portions  1201  and  1202  of the first conductor line  1200 , and the first diagonal line portion  1205  and the second conductor line  1300 . Herein, the capacitor  1500  needs not particularly be deployed at the aforementioned position. 
         [0127]    For example, the number of capacitors  1500  may be appropriately added and subtracted. 
         [0128]      FIG. 11  is a diagram regarding the second form of the metamaterial structure according to the embodiment of the present invention. Referring to  FIG. 11 , the capacitor  1500  may include only one capacitor  1500   b  deployed in the other one  1202  between both members of the first conductor line  1200 . 
         [0129]      FIG. 12  is a diagram regarding a third form of the metamaterial structure  1000  according to the embodiment of the present invention. Referring to  FIG. 12 , the capacitor  1500  may include only one capacitor  1500   d  deployed in the second conductor line  1300 . 
         [0130]    Besides, the capacitors may be appropriately deployed at desired locations with the desired number. For example, the metamaterial structure  1000  may include at least one of the first capacitor  1500   a , the second capacitor  1500   b , the third capacitor  1500   c , and the fourth capacitor  1500   d.    
         [0131]    Further, the position of the capacitor  1500  is not limited to the positions of the first capacitor  1500   a , the second capacitor  1500   b , the third capacitor  1500   c , and the fourth capacitor  1500   d  and may be deployed at different positions with the desired number. 
         [0132]    Meanwhile, an air capacitor may be used instead of the capacitor  1500 . In other words, a gap may be formed at a position provided by the capacitor  1500 . The gap may serve as the air capacitor. 
         [0133]      FIG. 13  is a diagram regarding a fourth form of the metamaterial structure  1000  according to the embodiment of the present invention. 
         [0134]    A first gap  1600   a , a second gap  1600   d , and a third gap  1600   d  may be formed in the first conductor line  1200  and the second conductor line  1300  instead of the positions at which the first capacitor  1500   a , the second capacitor  1500   b , and the fourth capacitor  1500   d  are deployed. Herein, the third capacitor  1500   c  may be omitted. 
         [0135]    Of course, when the capacitor  1500  is substituted with the air capacitor as described above, all capacitors  1500  need not particularly be substituted with the air capacitors and all or some of the capacitors  1500  may be substituted with the air capacitors. 
         [0136]    Herein, the gap  1600  serving as the air capacitor is not limited to the aforementioned example and may be appropriately deployed at desired positions with the desired number. 
         [0137]    Further, in the metamaterial structure  1000 , the gap  1600  which is the air capacitor and the capacitor  1500  may be simultaneously provided. 
         [0138]      FIG. 14  is a diagram regarding a fifth form of the metamaterial structure according to the embodiment of the present invention. 
         [0139]    Referring to  FIG. 14 , two gaps  1600   a  and  1600   b  and one capacitor  1500   d  are provided in the metamaterial structure  1000 . 
         [0140]    In other words, the capacitor  1500  and the gap  1600  may be appropriately combined and deployed at desired positions and at desired locations in the first conductor line  1200  and the second conductor line  1300 . 
         [0141]    When various forms of metamaterial structures  1000  of  FIGS. 6 to 9  and FIGS.  11  to  14  are summarized, the metamaterial structure  1000  includes the first conductor line  1200  and the second conductor line  1300  connected by the connection member  1400 , provided on opposite surfaces of the substrate  1100  to each other, and forming a twisted path from the top view, and the capacitors  1500  and the gaps  1600  may be provided at desired positions and desired locations on the first conductor line  1200  and the second conductor line  1300  at the appropriate number. Herein, the capacitor  1500  and the gap  1600  may be generally deployed at the positions symmetric to each other from the top view and a pattern having the twisted form, which is formed by the first conductor line  1200  and the second conductor line  1300  may also have a symmetric structure from the top view. 
         [0142]    Hereinafter, another modified example of the metamaterial structure  1000  will be described. 
         [0143]      FIGS. 15 to 17  are diagrams regarding a modified example in which a zigzag pattern is added to the metamaterial structure  1000  according to the embodiment of the present invention. 
         [0144]      FIG. 15  is a diagram regarding a sixth form of the metamaterial structure according to the embodiment of the present invention. 
         [0145]    Referring to  FIG. 15 , the first conductor line  1200  may include a zigzag pattern portion  1700 . The zigzag pattern portion  1700  may be formed in the first diagonal line portion  1205  of  FIG. 6 . That is, the first diagonal line portion  1205  may have a pattern formed in zigzags at the center thereof. The zigzag pattern portion  1700  generates capacitance by coupling between the paths forming the pattern to show a similar effect to a case in which the capacitor  1500  is inserted into the first conductor line  1200 . 
         [0146]    Meanwhile, even when the first conductor line  1200  has the zigzag pattern portion  1700 , the capacitor  1500  and the gap  1600  may be appropriately changed to the desired number at the desired position. 
         [0147]      FIG. 16  is a diagram regarding a seventh form of the metamaterial structure  1000  according to the embodiment of the present invention. 
         [0148]    Referring to  FIG. 16 , it may be illustrated that the capacitor  1500   d  is added to the second conductor line  1300  as compared with  FIG. 15 . Besides, some of the respective capacitors  1500   a ,  1500   b , and  1500   d  may be omitted or the respective capacitors  1500   a ,  1500   b , and  1500   d  may be modified to the gap  1600  which is the air capacitor and the capacitor  1500  may be inserted into the zigzag pattern portion  1700 . 
         [0149]    Meanwhile, in  FIGS. 15 and 16 , it is described that the zigzag pattern portion  1700  is formed in the first conductor line  1200  of  FIG. 6 , but the zigzag pattern portion  1700  may be formed in the second conductor line  1300 . 
         [0150]      FIG. 17  is a diagram regarding an eighth form of the metamaterial structure  1000  according to the embodiment of the present invention. 
         [0151]    Referring to  FIG. 17 , a first zigzag pattern portion  1700   a  may be provided to the first conductor line  1200  and a second zigzag pattern portion  1700   b  may be provided to the second conductor line  1300 . 
         [0152]    Hereinabove, various forms of metamaterial structures  1000  have been described with reference to  FIGS. 6 to 9  and  FIGS. 10 to 17 . However, the shape of the metamaterial structure  1000  according to the embodiment of the present invention is not limited to the aforementioned form. 
         [0153]    For example, in the metamaterial structure  1000 , the capacitor  1500 , the gap  1600  which is the air capacitor, and the zigzag pattern portion  1700  may be deployed at appropriate positions with the appropriate number as necessary. 
         [0154]    Further, the respective forms of the metamaterial structures  1000  may be combined with each other. 
         [0155]    The above description is illustrative purpose only and various modifications and transformations become apparent to those skilled in the art within a scope of an essential characteristic of the present invention. 
         [0156]    Accordingly, the various embodiments disclosed herein are not intended to limit the technical spirit but describe with the scope of the technical spirit of the present invention. The scope of the present invention should be interpreted by the appended claims and all technical spirit in the equivalent range is intended to be embraced by the appended claims of the present invention. 
       DESCRIPTION OF MARK 
       [0000]    
       
         
           
               1000 : metamaterial structure 
               1100 : substrate 
               1200 : first conductor line 
               1300 : second conductor line 
               1400 : connection member 
               1500 : power receiving module 
               1600 : gap 
               1700 : zigzag pattern portion 
               2000 : wireless power transmitting system 
               2100 : wireless power transmitting apparatus 
               2110 : AC-DC converter 
               2120 : frequency oscillator 
               2130 : power amplifier 
               2140 : impedance matcher 
               2150 : transmitting antenna 
               2200 : wireless power receiving apparatus 
               2210 : receiving antenna 
               2220 : impedance matcher 
               2230 : rectifier 
               2240 : DC-DC converter 
               2250 : battery 
             S: power source