Patent Publication Number: US-2016233585-A1

Title: Near field communications antenna and terminal including the same

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application claims the benefit of Korean Patent Application No. 10-2015-0020097 filed on Feb. 10, 2015 in the Korean Intellectual Property Office, the entire disclosure of which is incorporated herein by reference for all purposes. 
     BACKGROUND 
     1. Field 
     The following description relates to a near field communications (NFC) antenna and a terminal including the same. 
     2. Description of Related Art 
     Generally, near field communications (NFC) antennas may perform near field communications in a short range in a non-contact scheme to transmit data between terminals. 
     Recently, in order to decrease costs of NFC antennas, the size of NFC antennas has been continuously decreased in a range in which electrical specifications remain satisfied. 
     However, in accordance with the miniaturization of NFC antennas, an interior space accommodating the NFC antenna is decreased, and thus it may be difficult to satisfy desired levels of electrical performance. This problem may result in an increase in costs of NFC antennas, whereby the NFC antenna and a terminal including the same may not be price competitive. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter. 
     According to one general aspect, an NFC antenna includes: a first sheet including a magnetic material, the magnetic material including a thickness greater than 0 mm and less than or equal to about 0.05 mm; an antenna pattern disposed above the first sheet; and a second sheet disposed between the antenna pattern and the first sheet, wherein an interval between the antenna pattern and the magnetic material is at least about 0.03 mm. 
     The first sheet may further include an adhesive layer adhering the magnetic material to a terminal configured to perform NFC, and the magnetic material may include a ferrite. 
     The NFC antenna may further include an adhesive layer attached to one surface of the antenna pattern and a protective layer attached to another surface of the antenna pattern, wherein the antenna pattern includes a winding formed on a single-sided flexible printed circuit board (FPCB). 
     The second sheet may include an adhesive layer, a protective layer, and a film. 
     The protective layer may include an ink coating or a film. 
     The second sheet may include a protective layer disposed on an upper surface of the magnetic material. 
     The second sheet may further include an adhesive layer disposed on the protective layer and attached onto a lower surface of the film. 
     According to another general aspect, an NFC antenna includes: a first sheet including a magnetic material, the magnetic material comprising a thickness greater than 0 mm and less than or equal to about 0.05 mm; a first antenna pattern disposed above the first sheet; a second antenna pattern disposed above the first antenna pattern; and a second sheet disposed between the first antenna pattern and the first sheet, wherein an interval between the first antenna pattern and the magnetic material is at least about 0.02 mm. 
     The first sheet may further include an adhesive layer adhering the magnetic material to a terminal configured to perform NFC, and the magnetic material may include a ferrite. 
     The NFC antenna may further include an adhesive layer attached to one surface of the second antenna pattern and a protective layer attached to another surface of the second antenna pattern, wherein the first antenna pattern and the second antenna pattern include windings formed on a double-sided flexible printed circuit board (FPCB). 
     The NFC antenna may further include a film disposed between the first antenna pattern and the second antenna pattern, and adhesive layers attached to opposing surfaces of the film, wherein an interval between the first antenna pattern and the second antenna pattern is about 0.01 mm to about 0.2 mm. 
     The second sheet may include a protective layer disposed on an upper surface of the magnetic material, and an adhesive layer disposed on the protective layer and attached onto a lower surface of the first antenna pattern. 
     The protective layer may include an ink coating or a film. 
     Other features and aspects will be apparent from the following detailed description, the drawings, and the claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows a near field communications (NFC) antenna and a terminal including the same, according to an example. 
         FIG. 2  shows an NFC antenna and a terminal including the same, according to another example. 
         FIG. 3  is a view illustrating the antenna patterns illustrated in  FIGS. 1 and 2 . 
     
    
    
     Throughout the drawings and the detailed description, the same reference numerals refer to the same elements. The drawings may not be to scale, and the relative size, proportions, and depiction of elements in the drawings may be exaggerated for clarity, illustration, and convenience. 
     DETAILED DESCRIPTION 
     The following detailed description is provided to assist the reader in gaining a comprehensive understanding of the methods, apparatuses, and/or systems described herein. However, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be apparent to one of ordinary skill in the art. The sequences of operations described herein are merely examples, and are not limited to those set forth herein, but may be changed as will be apparent to one of ordinary skill in the art, with the exception of operations necessarily occurring in a certain order. Also, descriptions of functions and constructions that are well known to one of ordinary skill in the art may be omitted for increased clarity and conciseness. 
     The features described herein may be embodied in different forms, and are not to be construed as being limited to the examples described herein. Rather, the examples described herein have been provided so that this disclosure will be thorough and complete, and will convey the full scope of the disclosure to one of ordinary skill in the art. 
       FIG. 1  shows a near field communications (NFC) antenna  100  and a terminal  300  including the NFC antenna  100 , according to an example. 
     Referring to  FIG. 1 , the NFC antenna  100  includes a first sheet  110 , an antenna pattern  120 , and a second sheet  130 . 
     The first sheet  110  includes a magnetic material  111  of which a thickness exceeds 0 mm and is about 0.05 mm or less. More specifically, the thickness of the magnetic material may be greater than 0 mm and less than or equal to 0.05 mm. The magnetic material  111  includes a material having high permeability. 
     A unit cost of the magnetic material  111  per unit volume may be higher than those of other components of the NFC antenna  100 . Therefore, as the thickness of the magnetic material  111  is reduced, a unit cost of the NFC antenna  100  may be significantly decreased. 
     In a case in which the thickness of the magnetic material  111  is reduced to be less than about 0.05 mm, the unit cost of the magnetic material  111  per unit volume may not be relatively higher than those of the components of the NFC antenna  100 . In addition, as the thickness of the magnetic material  111  is reduced, a unit cost of the NFC antenna  100  required for satisfying a desired level of electrical performance may be increased. Therefore, in consideration of the unit cost of the material of the NFC antenna  100  and the unit cost of the NFC antenna  100  required for satisfying a desired level of electrical performance, the thickness of the magnetic material  111  may exceed 0 mm and may be about 0.05 mm or less. 
     For example, the magnetic material  111  included in the first sheet  110  includes a ferrite. The ferrite, a material having high permeability, amplifies a magnetic field of a signal used for NFC. However, the magnetic material  111  is not limited to the ferrite, and may be any material having permeability higher than that of air. 
     The first sheet  110  further includes an adhesive layer  150  on a lower surface of the magnetic material adhering the magnetic material  111  to a terminal  300  performing the NFC. Therefore, the adhesive layer  150  may include an adhesive tape, or the like, to thereby be attached to the terminal  300 . 
     Since the magnetic material  111  and the terminal  300  are closely adhered to each other by the adhesive layer  150 , even though the thickness of the magnetic material  111  is reduced, the magnetic field of the signal used for NFC is efficiently amplified. For example, as the thickness of the magnetic material  111  is reduced, the thickness of the adhesive layer  150  is reduced. Accordingly, a distance between the magnetic material and the terminal  300  is reduced as the thickness of the adhesive layer  150  is reduced. 
     The antenna pattern  120  is formed above the first sheet  110 . That is, the antenna pattern  120  is positioned above the first sheet  110  as illustrated in  FIG. 1 . For example, the antenna pattern  120  includes a winding formed on a single-sided flexible printed circuit board (FPCB). A detailed description of the winding will be described below with reference to  FIG. 3 . 
     For example, an adhesive layer  150  is attached onto one surface of the antenna pattern  120 , and a protective layer  160  is attached onto the other surface of the antenna pattern  120 . Here, the “one surface” of the antenna pattern  120  refers to a lower surface of the antenna pattern  120  facing the first and second sheets  110  and  130 , and “the other surface” of the antenna pattern  120  refers to an upper surface of the antenna pattern  120  opposing the one (lower) surface of the antenna pattern  120 . 
     For example, the adhesive layer  150  on the lower surface of the antenna pattern  120  is attached onto an upper surface of the second sheet  130 , and the protective layer  160  on the antenna pattern  120  is formed in the outermost portion of the NFC antenna  100 . The thickness of the adhesive layer  150  on the antenna pattern  120  may be adjusted to adjust a distance between the antenna pattern  120  and the first sheet  110 . 
     The protective layer  160  may also include an ink coating or film. The protective layer  160  is attached onto the upper surface of the antenna pattern  120 , and thus oxidation of and damage to the antenna pattern  120  may be prevented. 
     The second sheet  130  is formed between the antenna pattern  120  and the first sheet  110  so that an interval (e.g., vertical distance) between the magnetic material  111  included in the first sheet  110  and the antenna pattern  120  is at least about 0.03 mm. More specifically, the interval between the magnetic material  111  and the antenna pattern  120  may be 0.03 mm or more. For example, the second sheet  130  includes a film  140 , an adhesive layer  150  attached onto a lower surface of the film  140 , and a protective layer  160  attached onto a lower surface of the adhesive layer  150  on the lower surface of the film  140 . Here, the film  140  protects the antenna pattern  120 , and the adhesive layer  150  on the lower surface of the antenna pattern  120  is disposed on an upper surface of the film  140 . By adjusting thicknesses of the components included in the second sheet  130 , the interval between the antenna pattern  120  and the magnetic material  111  may be adjusted. 
     In a case in which the interval between the antenna pattern  120  and the magnetic material  111  is less than about 0.03 mm, it may be difficult to satisfy a desired level of electrical performance of the NFC antenna  100 . That is, as the thickness of the magnetic material  111  is reduced, it is significantly difficult to satisfy the desired level of electrical performance of the NFC antenna  100 , and in this case, if the interval between the antenna pattern  120  and the magnetic material  111  is also small, the unit cost of the NFC antenna  100  required for satisfying a desired level of electrical performance may be significantly increased. 
     Therefore, the interval between the antenna pattern  120  and the magnetic material may be about 0.03 mm or more. Here, a space obtained due to a decrease in the thickness of the magnetic material may be partially used to secure the interval between the antenna pattern  120  and the magnetic material. 
     Even when the interval between the antenna pattern  120  and the magnetic material is increased, so that an entire volume of the NFC antenna  100  is increased, the unit cost of the NFC antenna  100  may not be significantly increased. That is, since a unit cost of the second sheet  130  formed between the antenna pattern  120  and the magnetic material  111  may be relatively lower than that of the magnetic material  111 , the unit cost of the NFC antenna  110  may not be significantly increased. As the interval between the antenna pattern  120  and the magnetic material  111  is increased, it may be less difficult to satisfy the desired level of electrical performance of the NFC antenna  100 . Therefore, the thickness of the magnetic material  111 , of which the unit cost is high, may easily be reduced. As a result, the unit cost of the NFC antenna  100  may be decreased. 
       FIG. 2  is an NFC antenna  200  and the terminal  300  including the NFC antenna  300 , according to another example. 
     Referring to  FIG. 2 , the NFC antenna  200  includes a first sheet  210 , a first antenna pattern  221 , a second antenna pattern  222 , and a second sheet  230 . The first sheet  210  is similar to the first sheet  110  included in the NFC antenna  100 . 
     The NFC antenna  200  includes the first antenna pattern  221  and the second antenna pattern  222 , unlike the NFC antenna  100  which includes only one antenna pattern  120 . The first antenna pattern  221  is formed above the first sheet  210 . The second antenna pattern  222  is formed above the first antenna pattern  221 . That is, the first antenna pattern  221  is positioned above the first sheet  210  and below the second antenna pattern  222 , as illustrated in  FIG. 2 . 
     For example, the first antenna pattern  221  and the second antenna pattern  222  include windings formed on a double-sided FPCB. A detailed description of the windings will be described below with reference to  FIG. 3 . 
     For example, an adhesive layer  250  is attached onto one (lower) surface of the second antenna pattern  222 , and a protective layer  260  is attached onto the other (upper) surface of the second antenna pattern  222 . The adhesive layer  250  and the protective layer  260  are similar to the adhesive layer  150  and the protective layer  160  on the antenna pattern  120  included in the NFC antenna  100 . 
     A film  240  having adhesive layers is formed between the first antenna pattern  221  and the second antenna pattern  222 . The adhesive layer  250  attached onto the lower surface of the second antenna pattern is also attached onto an upper surface of the film  240 , and another adhesive layer  250  is attached onto a lower surface of the film  240 . The film  240  protects the first antenna pattern  221  and the second antenna pattern  222 . 
     The second sheet  230  is formed between the first antenna pattern  221  and the first sheet  210 , and an interval between the magnetic material  211  included in the first sheet  210  and the first antenna pattern  221  is at least about 0.02 mm. More specifically, the interval between the magnetic material  211  and the first antenna pattern  221  may be 0.02 mm or more. 
     For example, the second sheet  230  includes an adhesive layer  250  and a protective layer  260  disposed below the adhesive layer  250  of the second sheet  230 . By adjusting thicknesses of the components included in the second sheet  230 , the interval between the first antenna pattern  221  and the magnetic material  211  may be adjusted. 
     The interval between the first antenna pattern  221  and the magnetic material  211  is, for example, less than the interval between the first antenna pattern  120  and the magnetic material  111  in the NFC antenna  100 . That is, a volume of the NFC antenna  200  including both of the first antenna pattern  221  and the second antenna pattern  222  is larger than that of the NFC antenna  100  including the antenna pattern  120 . In addition, since the interval between the second antenna pattern  222  and the magnetic material  211  is larger than the interval between the first antenna pattern  221  and the magnetic material  211 , an average interval between the magnetic material  211  and the antenna patterns  221 ,  222  is larger than the interval between the first antenna pattern  221  and the magnetic material  211 . 
     Therefore, the interval between the first antenna pattern  221  and the magnetic material  211  may be about 0.02 mm or more. An interval between the first antenna pattern  221  and the second antenna pattern  222  may be about 0.01 mm to about 0.2 mm so that the average interval between the magnetic material  211  and the antenna patterns  221 ,  222  is about 0.03 mm or more. More specifically, the interval between the first antenna pattern  221  and the second antenna pattern  222  may be 0.01 mm to 0.2 mm so that the average interval between the magnetic material  211  and the antenna patterns  221 ,  222  is 0.03 mm or more. Therefore, a desired level of electrical performance of the NFC antenna  200  may be satisfied and a unit cost of the NFC antenna  200  may be decreased in a similar manner as compared to the NFC antenna  100 . 
       FIG. 3  is a view illustrating the antenna pattern  120 / 221 / 222  illustrated in  FIGS. 1 and 2 . 
     Referring to  FIG. 3 , the antenna pattern  120 / 221 / 222  includes a flexible printed circuit board  223 , a winding  224 , and a via  225 . 
     The flexible printed circuit board  223  is, for example, a single-sided flexible printed circuit board included in the antenna pattern  120  or a double-sided flexible printed circuit board included in the first antenna pattern  221  and the second antenna pattern  222 . 
     The winding  224  is wound in a loop form along edges of the flexible printed circuit board  223 . A magnetic field may pass through the center of the winding  224 . The winding  224  may be connected to an external terminal of the NFC antenna  200 . 
     In the case of the first antenna pattern  221  and the second antenna pattern  222  shown in  FIG. 2 , the via  225  electrically connects one surface and another, opposite surface of the double-sided flexible printed circuit board to each other. 
     The antenna pattern  120 , first antenna pattern  221  and the second antenna pattern  222  described with reference to  FIG. 3  are only examples. That is, the antenna patterns  120 ,  221 ,  222  are not limited to the loop form, and may be provided in any form as long as a magnetic field passing through the flexible printed circuit board and the winding may be adjusted. 
     As set forth above, according to the example embodiments disclosed herein, a desired level of electrical performance of an NFC antenna may be satisfied, and a unit cost of the NFC antenna may be decreased. 
     As a non-exhaustive example only, a terminal as described herein may be a mobile device, such as a cellular phone, a smart phone, a wearable smart device (such as a ring, a watch, a pair of glasses, a bracelet, an ankle bracelet, a belt, a necklace, an earring, a headband, a helmet, or a device embedded in clothing), a portable personal computer (PC) (such as a laptop, a notebook, a subnotebook, a netbook, or an ultra-mobile PC (UMPC), a tablet PC (tablet), a phablet, a personal digital assistant (PDA), a digital camera, a portable game console, an MP 3  player, a portable/personal multimedia player (PMP), a handheld e-book, a global positioning system (GPS) navigation device, or a sensor, or a stationary device, such as a desktop PC, a high-definition television (HDTV), a DVD player, a Blu-ray player, a set-top box, or a home appliance, or any other mobile or stationary device capable of wireless or network communication. In one example, a wearable device is a device that is designed to be mountable directly on the body of the user, such as a pair of glasses or a bracelet. In another example, a wearable device is any device that is mounted on the body of the user using an attaching device, such as a smart phone or a tablet attached to the arm of a user using an armband, or hung around the neck of the user using a lanyard. 
     While this disclosure includes specific examples, it will be apparent to one of ordinary skill in the art that various changes in form and details may be made in these examples without departing from the spirit and scope of the claims and their equivalents. The examples described herein are to be considered in a descriptive sense only, and not for purposes of limitation. Descriptions of features or aspects in each example are to be considered as being applicable to similar features or aspects in other examples. Suitable results may be achieved if the described techniques are performed in a different order, and/or if components in a described system, architecture, device, or circuit are combined in a different manner, and/or replaced or supplemented by other components or their equivalents. Therefore, the scope of the disclosure is defined not by the detailed description, but by the claims and their equivalents, and all variations within the scope of the claims and their equivalents are to be construed as being included in the disclosure.