Patent Publication Number: US-2016240301-A1

Title: Magnetic Member and Wireless Power Transmission Device Comprising Same

Description:
TECHNICAL FIELD 
     The present invention relates to a magnetic member applied to a wireless power conversion device. 
     BACKGROUND ART 
     A magnetic material is used in an information technology (IT) component module for a wireless power transmission such as a near field communication (NFC) module, and due to the use of the magnetic material, an effort to enhance a function and a performance of transmission efficiency, i.e., wireless power transmission efficiency, by minimizing electromagnetic energy loss by employing an electromagnetic shielding material, i.e., a magnetic material, has continued beyond a practice of relying only on a coil design. 
     In terms of the electromagnetic shielding material formed of a magnetic material, a shielding material capable of satisfying a function of wireless power transmission is necessary, but such a shielding material shows a limit in compatibility due to a diversification in standard methods for wireless power transmission. Representative examples of standard methods for the wireless power transmission includes wireless power consortium (WPC), alliance for wireless power (A4WP), and power matters alliance (PMA), and the wireless power transmission methods are technically classified into magnetic induction methods and magnetic resonance methods. 
     Specifically in terms of an IT component, whether a permanent magnet is adopted inside a transmitting unit or a receiving unit makes a major difference, that is, according to whether the permanent magnet is adopted, much difference is shown in wireless power transmission efficiency depending on each standard, and an application to various designs is different. 
     According to an A1-type standard of a WPC transmitting unit, a permanent magnet is included in a center of a power transmitting unit regardless of an implemented function of magnetic induction or magnetic resonance. The reason the permanent magnet is installed is to correct positions of a transmitting antenna and a receiving antenna to optimum positions. For each function to be exhibited with a maximum performance consistent with the variety of the above-mentioned standard methods, each standard requires a different material and structure of a magnetic member. For this, there is a problem that a material and a structure of the magnetic members have to be changed, but a magnetic material having compatibility consistent with the variety of standard methods described above has yet not been developed. 
     In addition, antennas of NFC and WPC systems are each configured to include a certain area of a coil to be provided with energy required for an operation of a microchip from a reader. A magnetic field formed by alternating current (AC) power energy generated from a primary coil of the reader passes through a coil of an antenna to induce a current, and a voltage is generated due to an inductance of the antenna. The voltage generated as described above is used as power for transmitting data or charging a battery. Efficiency of a power transmission between the primary coil and a secondary coil is associated with an operating frequency, a cross-sectional area of the secondary coil, and a distance and an angle between the primary coil and the secondary coil, but an operating distance is relatively short due to a limit of a current amount which flows at an antenna side. To secure the operating distance described above, a magnetic layer which serves a function of shielding electromagnetic-waves is formed on the secondary coil of the antenna. A need for a soft magnetic substrate capable of securing a minimum operating distance of the antenna side formed as above while minimizing a manufacturing cost is growing. 
     DISCLOSURE 
     Technical Problem 
     The present invention is directed to providing a magnetic member capable of implementing a high efficiency wireless power transmission and minimizing influence of a permanent magnet in a wireless power transmission method that requires the permanent magnet while being compatible with a variety of standards of wireless power transmission methods. 
     The present invention is also directed to providing a soft magnetic substrate capable of forming a recognition distance of the soft magnetic substrate from a transmission side to be a minimum recognition distance or more as well as minimizing a manufacturing cost by forming an opening at the central portion of the soft magnetic layer disposed above a coil pattern to reduce an area that the soft magnetic layer occupies. 
     Technical Solution 
     One aspect of the present invention provides a magnetic member which includes a cross section provided with a first width x of a first direction and a second width y of a second direction perpendicular to the first direction, and a thickness z which extends from the cross section, wherein a ratio of an area of the cross section to the thickness z is in the range of 1:(0.0002˜1). 
     Another aspect of the present invention provides a magnetic member which includes a soft magnetic layer having a cross section provided with a first width x of a first direction, a second width y of a second direction perpendicular to the first direction, and a thickness z which extends from the cross section, and an opening in the thickness z direction, and a coil pattern on the soft magnetic layer, wherein the soft magnetic layer includes an area which corresponds to the coil pattern, and an area which extends from the area which corresponds to the coil pattern. 
     Advantageous Effects 
     The magnetic member according to the embodiments of the present invention can provide effects of being compatible with a variety of standard methods of wireless power transmission and implementing high power transmission efficiency while minimizing influence of a permanent magnet in a power transmission method that requires the permanent magnet. 
     More specifically, by minimizing influence of a permanent magnet in a latest wireless power transmitting unit and receiving unit having a permanent magnet regardless of employing a permanent magnet in a transmitting unit and a receiving unit of Tx-A1 (a representative standard on a transmitting unit including a permanent magnet) and Tx-A11 (a representative standard on a transmitting unit without a permanent magnet), the magnetic member according to the embodiments of the present invention has an advantageous effect of implementing high efficiency wireless power transmission. 
     In addition, the magnetic member according to the embodiments of the present invention can maximize wireless power transmission efficiency by applying an excellent magnetic material effective in wireless power transmission and implement an advantage of extending applications to include small hand-held gadgets such as a mobile phone or the like, various devices of telecommunications and information technology (IT), and large devices such as an organic light emitting diode (OLED), a hybrid electric vehicle (HEV), an electric vehicle (EV) etc. because a variety of magnetic material is applicable regardless of new standards. 
     Furthermore, the soft magnetic substrate according to the embodiments of the present invention can form a recognition distance of the soft magnetic substrate from a transmitter side to be a minimum recognition distance or more as well as reducing the area that the soft magnetic layer occupies on the magnetic member to minimize a manufacturing cost by forming the opening at the central portion of the soft magnetic layer disposed above the coil pattern. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a conceptual diagram illustrating a structure of a magnetic member according to one embodiment of the present invention; 
         FIGS. 2 and 3  are conceptual diagrams illustrating modified embodiments of structures of magnetic members according to one embodiment of the present invention; 
         FIGS. 4 to 7  are graphs illustrating experimental data according to one embodiment of the present invention; 
         FIG. 8  is a diagram illustrating a wireless power conversion (WPC) system or a near field communication (NFC) system in which a magnetic member according to another embodiment of the present invention is applied; 
         FIGS. 9 to 10  are conceptual diagrams illustrating a magnetic member which forms a transmitting device or a receiving device described in  FIG. 8  according to one embodiment of the present invention; 
         FIG. 11  is a cross-sectional view of a soft magnetic substrate according to yet another embodiment of the present invention; 
         FIGS. 12 and 13  are views for describing a magnetic member according to one embodiment of the present invention; and 
         FIG. 14  is a table for describing recognition distances of magnetic members according to embodiments of the present invention, and  FIG. 15  is a graph for describing the recognition distances of the magnetic members according to the embodiments of the present invention. 
     
    
    
     MODES OF THE INVENTION 
     Hereinafter, configurations and operations according to the embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the description referencing the accompanying drawings, like elements are designated by the same reference numerals regardless of reference numbers, and duplicated descriptions thereof will be omitted. Although the terms “first,” “second,” etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. 
       FIG. 1  is a conceptual diagram illustrating a structure of a magnetic member according to one embodiment of the present invention. 
     Referring to  FIG. 1 , a magnetic member  10  according to one embodiment of the present invention is provided with a cross section which includes a first width x of a first direction, a second width y of a second direction perpendicular to the first direction, and a thickness z which extends from a cross section, and the magnetic member  10  may be formed in a structure that satisfies a ratio of an area of the cross section to the thickness z in the range of 1:(0.0002˜1). 
     In the structure of  FIG. 1 , a cross sectional structure of a rectangle having a width and a length is illustrated, but the cross section is not limited thereto, and any sheet member having a cross sectional shape in various structures of a single closed curve having orientations of a first direction and a second direction and a uniform thickness is included in the scope of the present invention. 
     As illustrated, the magnetic member  10  is provided with the first width x as a length of the first direction and the second width y as a length of the second direction y perpendicular to the first width x, and the first width x is defined as the longest line segment of the cross section in a horizontal direction and the second width y is defined as the longest line segment in a perpendicular direction to the first width. In addition, an embodiment of the present invention satisfies the ratio of the area of the cross section area serving as a plane formed by the first width and the second width to the thickness of the magnetic member in the range of 1:(0.0002˜1). 
     (Particularly, the first width x is defined as the longest line segment of the cross section in the horizontal direction and the second width y is defined as the longest line segment in the perpendicular direction to the first width, and an applied unit in defining the ratio of the area to the thickness as described above is the millimeter (mm). When the unit is changed, because a numerical ratio changes at a rate of 10a (a is a rational number), the applied unit is provided (expressed), and the determined ratio needs to be calculrated and defined in terms of a comparison. In addition, in the method of calculating the ratio, a calculated ratio is defined by applying only numerical values and disregarding units because an area unit ‘mm 2 ’ and a thickness unit ‘mm’ are physically different from each other.) 
     In a wireless power transmission module including an ordinary magnetic member, when a permanent magnet is positioned at the center of a transmission antenna, a magnetic member at a receiving device is influenced, which causes a degradation phenomenon of permeability which is formed by a magnetic field induced by currents flowing at coils of transmitting and receiving devices. While the influence on a soft magnetic core of the transmitting device is less serious because of a thickness of several millimeters and a volume even though the permeability of a certain portion adjacent to the permanent magnet is degraded, a soft magnetic sheet as thin as a thickness of 0.1 mm to 0.3 mm retaining a high permeability characteristic in horizontal and vertical directions shows degradation of an induction phenomenon induced by an alternate current (AC) magnetic field formed by the coil because of a magnetization behavior caused by an adjacent permanent magnet. As a result, a leakage of electromagnetic energy at a transmitting antenna and a receiving antenna is not prevented, and thereby transmission efficiency is degraded. On the contrary, in an embodiment of the present invention that satisfies the ratio of an area of the cross section to a thickness in the range of 1:0.0002 to 1:1, the degradation phenomenon of the permeability is remarkably removed and the influence of the permanent magnet may be minimized. 
     When the above-described range of the ratio is satisfied, not only is transmission efficiency of the wireless power transmission increased, but also compatibility which is applicable to be compatible with various standards of power transmission regardless of the existence of a permanent magnet, which is applied to the various standards, is secured. On the contrary, in the case of deviation from the above-described range, the power transmission efficiency drops noticeably, and while it may be applied to a specific standard, it implements characteristics which are not proper to other standard methods due to a severe influence by the permanent magnet. 
     The magnetic member  10  according to one embodiment of the present invention, regardless of shape, is more preferable in that it satisfies an entire volume implemented as a magnetic substance in the range of 10 3  mm 3  to 10 12  mm 3  which satisfies the range of the above-described ratio of the area of the cross section to the thickness. Compatibility and transmission efficiency of the wireless power transmission is further enhanced when the ratio of the area of the cross section of the magnetic layer to the thickness thereof satisfies the above-described range of volume. 
       FIG. 2  illustrates conceptual diagrams of structures of magnetic members applied to a wireless power transmission or reception module according to one embodiment of the present invention. 
     According to  FIG. 2 , the magnetic member according to one embodiment of the present invention, as illustrated in  FIG. 2(A) , may be implemented by a single layer of a non-stacked structure which is configured to fall within the range which satisfies the ratio of the area of the cross section to the thickness according to the above-described embodiment of  FIG. 1 , or may be implemented by a stacked layer structure by a plurality of unit sheets of  110   a  to  110   d  as illustrated in  FIG. 2(B)  and may be implemented to fall within the range which satisfies the ratio of the area of the cross section to the thickness according to the above-described embodiment of  FIG. 1 . 
     Particularly, in the case of the stacked layer structure of the magnetic member as illustrated in  FIG. 2(B) , when implemented as a simple stacked layer structure implemented by each separated structure without interposing a medium substance such as an adhesive or the like, the influence of a permanent magnet may be dispersed to each separate unit sheet, thereby preventing the transmission efficiency from degrading in a standard method of a wireless power transmission module with the existence of a permanent magnet, in addition to which the dispersing efficiency of the above-described influence by the permanent magnet may be further enhanced by interposing an insulating layer such as an adhesive, an adhesive film or the like between the unit members of the sheets. In the case, it is preferable that a thickness of the unit sheet satisfies the range of 18 um to 200 um, and in the case of the stacked layer structure, it is preferable that a stacked layer structure stacked in the range of 2 layers to 30 layers be implemented while satisfying the ratio of the area of the cross section to the thickness in the magnetic member according to the above-described embodiment of the present invention in terms of efficiency that may be outside of the influence of the permanent magnet. 
     In the structure of  FIG. 2 , the magnetic member  10  may be applied to a wireless charging module as a structure further including cover films  20 A and  20 B on surfaces of the magnetic member  10 , and in this case, a coil  20  for wireless power transmission may be additionally disposed on an upper surface of the magnetic member  10 .  FIG. 3  illustrates a structure of the magnetic member, a placement of the coil  20 , and a modified arrangement of the cover film  20 A according to one embodiment of the present invention. 
     Further, the magnetic member according to one embodiment of the present invention of  FIGS. 1 and 2  may be formed of a composite material of a polymer and a metallic-alloy based magnetic powder formed of one element or a combination of two or more elements selected from Fe, Ni, Co, Mo, Si, Al and B, or may be formed by a metallic-alloy based magnetic ribbon. In the embodiment of the present invention, metallic alloys in a crystalline state or an amorphous state having a shape of a very thin band, a string, or a belt, are collectively referred to as a “ribbon.” 
     In addition, although the term “ribbon” defined in the embodiment of the present invention is a metallic alloy in principle, a particular term “ribbon” is used due to an appearance of a shape, and Fe(Co)—Si—B is used as a main material to form the ribbon, which may be manufactured in various types of compositions by adding additives such as Nb, Cu, Ni, etc. In a broad sense of the ribbon, an applicable material may include a fiber, a vinyl, a plastic, a metal, an alloy, or the like, but the ribbon in daily life may be manufactured chiefly in a form of a fiber or vinyl and may be used for the purpose of binding an object, decoration, or the like. 
     Alternatively, the magnetic member may be formed of a composite material of a polymer and a ferrite-based powder formed of a combination of two or more elements selected from Fe, Ni, Mn, Zn, Co, Cu, Ca, and O, or formed of a sintered ferrite, and a shape may be implemented as a sheet structure. For instance, the magnetic member according to one embodiment of the present invention may be formed of Fe—Si—B and a MnZn-based ferrite. 
     In any case, it is preferable that the magnetic member satisfies the ratio of the area of the cross section to the thickness z in the range of 1:(0.0002˜1), and more preferably that it satisfies a volume of the magnetic member in the range of 10 3  mm 3  to 10 12  mm 3 . 
     EXPERIMENTAL EXAMPLE 1 
     In experimental example 1, a transmission efficiency of a wireless power transmission depending on a thicknesses of a magnetic member formed of Fe—Si—B material and a magnetic member formed of MnZn ferrite material is measured. A variation in the thickness of a sheet is given in the range of 0.1 mm to 0.3 mm, an LF5055ANT is applied as an antenna for the wireless power transmission, and a thickness of the coil is uniformly set to 0.1 mm. An area of the magnetic member applied is set to 50 mm by 55 mm (an area of 2750 mm 2 ), a space between the magnetic member and the antenna is 0.03 mm, and an input power is applied in the range of 2.5 W to 3.5 W (power transmission methods were Tx-A11 and Tx-A1). 
     As a material for the magnetic member, a result illustrated in  FIG. 4  is from applying an Fe—Si—B ribbon, and a result illustrated in  FIG. 5  is from applying the MnZn ferrite. Referring to  FIGS. 4 and 5 , in any case the range of one embodiment of the present invention is satisfied, and the transmission efficiency is securable up to the range of 65% to 69% when the thickness of the sheet is increased, and thus it is confirmed that a desired degree (transmission efficiency for proper wireless charging) may be secured even in different transmission methods. 
     EXPERIMENTAL EXAMPLE 2 
     Graphs of experimental results in  FIGS. 6 and 7  illustrate transmission efficiencies measured depending on an area of a sheet according to one embodiment of the present invention. 
     To measure transmission efficiency depending on an area of a magnetic member formed of an Fe—Si—B material and a magnetic member formed of an MnZn ferrite material, the areas of the sheets were changed from 1000 mm 2  to 3000 mm 2  while measuring the transmission efficiency. 
     Two thicknesses of the sheets of 0.1 mm and 0.25 mm were applied, an antenna applied for wireless power transmission is a lead frame LF5055ANT at a size of 50 mm by 55 mm, and a thickness of a coil is uniformly set to 0.1 mm. An area of the magnetic member applied is 50 mm by 55 mm (an area of 2750 mm 2 ) as a maximum size, a space between the magnetic member and the antenna is 0.03 mm, and an input power is applied in the range of 2.5 W to 3.5 W (power transmission methods were Tx-A11 and Tx-A1). 
     As confirmed from the results in  FIGS. 6 and 7 , in spite of the difference of the transmission methods, the transmission efficiency in the range according to one embodiment of the present invention is securable up to the range of 62% to 69% when the area of the sheet is increased within the range satisfying the embodiment of the present invention, and thus it is confirmed that a desired degree (transmission efficiency for proper wireless charging) may be secured even in different transmission methods. 
     When the above-described results are taken together, by implementing the magnetic member according to one embodiment of the present invention to satisfy the ratio of the area of cross section to the thickness in the range of 1:(0.0002˜1), or, in addition, by implementing a volume of the magnetic member to satisfy the range of 10 3  mm 3  to 10 12  mm 3 , a high efficiency of wireless power transmission may be expected regardless of equipping a permanent magnet, an advantage of resolving a compatibility problem depending on differences in transmission methods is implemented, and a wide use of magnetic members which allows a variety of magnetic material to be selected regardless of a new standards is achievable. That is, by controlling an area and a thickness of the magnetic member, the highest level of transmission efficiency with various structures of magnetic members may be implemented and expansion to diverse application fields may be expected. 
     Hereinafter, an application of a magnetic member according to another embodiment of the present invention will be described. The above-described magnetic member may be applied to implement this embodiment as a matter of course.  FIG. 8  is a view illustrating a wireless power conversion (WPC) system or a near field communication (NFC) system in which a magnetic member according to another embodiment of the present invention is applied. 
     Referring to  FIG. 8 , the WPC system or the NFC system is formed to include a transmitting device  200  and a receiving device  100 . The transmitting device  200  is formed to include a transmitter coil  210 , and the receiving device  100  is formed to include a receiver coil  110 . The transmitter coil  210  is connected with a power source  201 , and the receiver coil  110  is connected with a circuit  101 . 
     The power source  201  may be an AC power source which provides an AC power at a predetermined frequency, and an AC current flows in the transmitter coil  210  by the power supplied from the power source  201 . 
     When the AC current flows in the transmitter coil  210 , an AC current is also induced in the receiver coil  110  physically separated from the transmitter coil  210  by electromagnetic induction. 
     The induced current in the receiver coil  110  is transferred to the circuit  101 , and is then rectified to operate the receiving device  100 . 
     Meanwhile, in the case of WPC system, the above-described transmitting device  200  may be formed as a transmission pad, and the receiving device  100  may be formed as a part of configurations in a handheld terminal, a household or personal electronic appliance, a transportation vehicle, or the like where the wireless power transmitting and receiving technologies are applied, or a handheld terminal, a household or personal electronic appliance, a transportation vehicle, or the like where the wireless power transmitting and receiving technologies are applied may only include the receiving device  100  or alternatively may include both of the wireless power transmitting device  200  and the wireless power receiving device  100 . 
     In addition, in the case of NFC system, the above-described transmitting device  200  may be formed as a reader and the receiving device  100  may be formed as a tag. 
       FIGS. 9 and 10  are conceptual diagrams illustrating a magnetic member which forms a transmitting device or a receiving device illustrated in  FIG. 8  according to another embodiment of the present invention. More particularly,  FIG. 9  is a top plan view of a magnetic member according to one embodiment of the present invention, and  FIG. 10  is a cross sectional view of a magnetic member according to one embodiment of the present invention. 
     A structure of the magnetic member according to one embodiment of the present invention will be described with reference to  FIGS. 9 and 10 . The magnetic member according to the embodiment of the present invention may also be formed as a structure of a sheet or a substrate provided with a cross section which includes a first width x of a first direction, a second width y of a second direction perpendicular to the first direction, and a thickness z which extends from the cross section, particularly in the embodiment of the present invention a soft magnetic layer which includes an opening is formed in a thickness z direction. 
     That is, as illustrated in  FIGS. 9 and 10 , the magnetic member according to one embodiment of the present invention is formed to include a soft magnetic layer  120  and a coil pattern  110  which forms a receiving coil, and may be formed further including a protective layer  111  having the coil pattern  110 , an adhesive layer  130 , and a black film layer  127 . 
     The coil pattern  110  is formed as a coil, and the coil may be formed as 3 to 4 turns. 
     The coil pattern  110  may be formed to be included in the protective layer  111 . 
     Here, an inductance of the coil pattern  110  may be formed to be about 3.2 H, and the coil pattern  110  may be formed to have a width of 3 mm. 
     Meanwhile, the coil pattern  110  may be formed as various structures of polygons besides the shape illustrated in  FIG. 10 . 
     In addition, a soft magnetic layer  120  may be formed above the coil pattern  110 , and an opening  125  is included inside the soft magnetic layer  120 . 
     More specifically, as illustrated in  FIGS. 9 and 10 , the soft magnetic layer  120  may be disposed to include an area a which corresponds to the coil pattern  110 , and areas b and c which extend from the area a which corresponds to the coil pattern  110 . Here, the soft magnetic layer  120  may be formed to occupy in the range of 25% to 50% of an area on the magnetic member. That is, the soft magnetic layer  120  may be implemented to occupy in the range of 25% to 50% of the entire area of the magnetic member including the opening. 
     In addition, the soft magnetic layer  120  may be disposed to include the area a which corresponds to the coil pattern  110 , and the areas b and c which extend 5 mm from the area a which corresponds to the coil pattern  110 . 
     Alternatively, the soft magnetic layer  120  may be disposed to include the area c which extends 5 mm of widths d 2  and d 3  toward the opening  125  from the area a which corresponds to the coil pattern  110 , and the area b which extends 1 mm of a width d 1  toward an outer edge of the soft magnetic substrate from the area a which corresponds to the coil pattern  110 . When the opening  125  is formed at the central portion of the soft magnetic layer  120  as described above, a recognition distance of a soft magnetic substrate from a reader may be formed to be a minimum recognition distance or more while reducing the area of the soft magnetic layer  120 . 
     Meanwhile, the soft magnetic layer  120  may be formed by performing a punching process on an integrated soft magnetic layer, or formed as a combined structure by combining a plurality of separated magnetic structures. In other words, in the case that the soft magnetic layer  120  is formed as a combined structure by combining a plurality of separated magnetic structures, the soft magnetic layer  120  may be formed by assembling separated structures in a shape of a rectangle or a stick, or by assembling a L-shaped structure and a ┐-shaped structure. 
     The soft magnetic layer  120  formed as described above may further include an insulating material layer disposed between the coil pattern and the soft magnetic layer. The insulating material layer may be formed to include a material layer having an insulating property such as an adhesive layer, a protective film, or the like. As an embodiment, the coil pattern  110  may be provided with a protective layer  111  for the purpose of protecting the coil pattern  110 , and may be bonded on the protective layer  111  by a medium of the adhesive layer  130 . Further, at an upper surface or a lower surface of the soft magnetic layer  120 , the shielding layer  127  may be formed, wherein the black film layer formed as the shielding layer will be taken as an example for explanation. 
     Meanwhile, the soft magnetic layer  120  may be formed to have a relative permeability in the range of 50 to 200, and may be formed of a ferrite which includes at least any one of Fe, Ni, Co, Mn, Al, Zn, Cu, Ba, Ti, Sn, Sr, P, B, N, C, W, Cr, Bi, Li, Y and Cd. 
     In addition, as illustrated in  FIG. 10 , the black film layer serving as the shielding layer  127  may be disposed on one surface and the other surface of the soft magnetic layer  120 . 
     Further, according to another embodiment of the present invention, a second soft magnetic layer may be formed to be disposed in the opening  125 . 
     The second soft magnetic layer may be formed of a material having a different permeability from that of the soft magnetic layer  120 , and may be formed of a ferrite including at least any one of Fe, Ni, Co, Mn, Al, Zn, Cu, Ba, Ti, Sn, Sr, P, B, N C, W, Cr, Bi, Li, Y, and Cd, in the same manner as the soft magnetic layer  120 . 
     FIG. 11  is a cross sectional view of a soft magnetic substrate according to still another embodiment of the present invention. 
     In the same manner as the embodiment illustrated in  FIGS. 9 and 10 , a soft magnetic substrate according to the embodiment of  FIG. 11  is formed to include a coil pattern  110  and a soft magnetic layer  120 , and is formed to further include a protective layer  111  which includes the coil pattern  110 , an adhesive layer  130 , and a black film layer serving as a shielding layer  127 . 
     The coil pattern  110  is formed to be included in the protective layer  111 , and the soft magnetic layer  120  which includes an opening  125  therein is formed above the coil pattern  110 . 
     In the embodiment of  FIG. 11 , the soft magnetic layer  120  may be formed to be disposed only at an area a which corresponds to the coil pattern  110 . 
     When the opening  125  is formed at the central portion of the soft magnetic layer  120 , a recognition distance of the soft magnetic substrate from a reader may be formed to be a minimum recognition distance or more while minimizing the area of the soft magnetic layer  120 . 
     In the same manner, the soft magnetic layer  120  formed as above may be bonded above the protective layer  111  which includes the coil pattern  110  by a medium of the adhesive layer  130 , and the shielding layer  127  as the black film layer may be disposed on one surface and the other surface of the soft magnetic layer  120 . 
       FIGS. 12 and 13  are views for describing a magnetic member according to one embodiment of the present invention. 
       FIG. 12  is a soft magnetic substrate according to a conventional art, in which a soft magnetic layer  120  is formed across the entire surface of a soft magnetic substrate, while a magnetic member having a soft magnetic according to one embodiment of the present invention as illustrated in  FIG. 13  is formed to include a soft magnetic layer  120  having an opening  125 . 
     More specifically, the soft magnetic substrate according to one embodiment of the present invention may form the soft magnetic layer  120  including the opening  125  by performing a punching process on an integrated soft magnetic layer, or the soft magnetic layer  120  may be formed by combining a plurality of separated magnetic structures. 
       FIG. 14  is a table for describing recognition distances of magnetic members according to embodiments of the present invention, and  FIG. 15  is a graph for describing the recognition distances of the magnetic members according to the embodiments of the present invention. 
     Referring to  FIGS. 14 and 15 , a case of forming a sheet size of the soft magnetic substrate according to the conventional art and sheet sizes of magnetic members according to first to a fifth embodiments of the present invention as 42 mm by 58 mm will be described. 
     Meanwhile, the horizontal axis of  FIG. 15  represents an area percentage of a magnetic member that a soft magnetic layer occupies, and the vertical axis represents a recognition distance recognizable from a reader. 
     A soft magnetic substrate of a conventional art  600  has an exemplary embodiment covering a soft magnetic layer above a coil pattern required much expensive ferrite material when forming the soft magnetic layer because an opening is not formed at the soft magnetic layer, and the recognition distance from the reader is 45 mm. 
     A magnetic member according to a first embodiment  610  has an exemplary embodiment in which the soft magnetic layer  120  extends by a width d 1  of 1 mm toward an edge end of the magnetic member, and extends by widths d 2  of 2 mm and d 3  of 4 mm from the coil pattern  110  toward the opening  125 . The recognition distance from the reader is 45 mm, and the area percentage of the magnetic member that the soft magnetic layer  120  occupied is 49%. 
     In addition, a magnetic member according to a second embodiment  620  has an exemplary embodiment in which the soft magnetic layer  120  extends by a width d 1  of 1 mm toward an edge end of the soft magnetic substrate, and extends by widths d 2  of 1 mm and d 3  of 3 mm from the coil pattern  110  toward the opening  125 . The recognition distance from the reader is 43 mm, and the area percentage of the magnetic member that the soft magnetic layer  120  occupied is 42%. 
     In addition, a magnetic member according to a third embodiment  630  has an exemplary embodiment in which a width d 1  of the soft magnetic layer  120  does not extend toward an edge end of the magnetic member, and the soft magnetic layer  120  extends by widths d 2  of 1 mm and d 3  of 3 mm from the coil pattern  110  toward the opening  125 . The recognition distance from the reader is  39  mm, and the area percentage of the magnetic member that the soft magnetic layer  120  occupied is 36%. 
     In addition, a magnetic member according to a fourth embodiment  640  has an exemplary embodiment in which a width d 1  of the soft magnetic layer  120  does not extend toward an edge end of the soft magnetic substrate, a width of the soft magnetic layer  120  does not extend from the coil pattern  110  toward a first side of the opening  125 , and the soft magnetic layer  120  extends by a width d 3  of 2 mm from the coil pattern  110  toward a second side of the opening  125 . The recognition distance from the reader is 37 mm, and the area percentage of the magnetic member that the soft magnetic layer  120  occupied is 29%. 
     Lastly, a magnetic member according to a fifth embodiment  650  has an exemplary embodiment in which a width d 1  of the soft magnetic layer  120  does not extend toward an edge end of the soft magnetic substrate, and widths d 2  and d 3  of the soft magnetic layer  120  does not extend from the coil pattern  110  toward a first and a second sides of the opening  125 . The recognition distance from the reader is 29 mm, and the area percentage of the magnetic member that the soft magnetic layer  120  occupied is 26%. 
     In the third to fifth embodiments  630 ,  640  and  650  of the present invention, although the soft magnetic layer  120  does not extend from the coil pattern  110 , the soft magnetic layer  120  is formable a bit off the coil pattern  110  because the coil pattern  110  is a structure having a curvature. 
     Accordingly, the magnetic member according to the embodiments of the present invention may form the recognition distance of the soft magnetic substrate from a reader to be a minimum recognition distance of 25 mm or more as well as reducing the area that the soft magnetic layer occupies at the magnetic member by forming the opening at the central portion of the soft magnetic layer disposed above the coil pattern. 
     While the invention has been shown and described with reference to certain exemplary embodiments thereof, it should be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. The inventive concept of the present invention is not limited to the embodiments described above, but should be defined by the claims and equivalent scope thereof. 
     INDUSTRIAL APPLICABILITY