JP2011034465A - Reader/writer device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To extend the communication range of a reader/writer device. <P>SOLUTION: The reader/writer device includes: a display part 14; an upper case 2A for holding the display part 14; and a loop antenna 21 arranged on the outer surface of the upper case 2A and wound around the display part 14. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to a reader / writer device.

  Conventionally, a PDA that has an RFID (Radio Frequency Identification) antenna and has an RFID function for reading information recorded on an IC (Integrated Circuit) tag (RFID tag) or a non-contact IC card in a non-contact manner using the RFID antenna Reader / writer devices such as (Personal Digital Assistant) are known. For example, the RFID tag is attached to a manufactured product, and identification information of the product is recorded. The non-contact IC card is used, for example, for recording information on tickets for trains, buses, etc., and electronic money.

  In particular, the use of 13.56 MHz band RFID tags and contactless IC cards is rapidly expanding. Hereinafter, the RFID tag and the non-contact IC card are collectively referred to as an RFID tag.

  When communication is performed using a 13.56 MHz band RFID, a loop antenna is used as the RFID antenna, and communication is performed using a magnetic field instead of an electric field.

  Communication using a magnetic field using a loop antenna is characterized in that communication is facilitated when the loop antenna in the RFID tag and the loop antenna of the reader / writer device face each other.

  Further, when the loop area of the loop antenna is increased or the number of turns of the loop antenna is increased, the communication range of the reader / writer device is increased. In addition, if there is a metal part near the loop antenna, the magnetic field output from the loop antenna is obstructed and the communication range cannot be widened. In addition, the reader / writer device has a short communication distance (about 0 to 100 mm).

  For this reason, when communicating with RFID in the 13.56 MHz band, in order to widen the communication range, the number of turns of the loop antenna is increased, the area of the loop antenna is increased, and metal parts are provided in the vicinity of the loop antenna. It is important not to place Further, in order to increase the communication range, it is important to reduce communication loss (communication distance loss) corresponding to the distance between the loop antenna in the RFID tag and the loop antenna of the reader / writer device.

  In addition, a technology that can reduce the installation area by arranging a loop antenna on the back side of the liquid crystal panel is also known (see, for example, Patent Document 1).

JP 2007-255743 A

  Since there is little empty space in the case of the reader / writer device, it is difficult to secure the antenna mounting position. For this reason, the loop area of the loop antenna is reduced. For example, in the technique of Patent Document 1, a loop antenna is arranged on the back side of the liquid crystal panel. In this configuration, the loop area of the loop antenna is reduced.

  Also, when there is a metal part inside the reader / writer device (for example, when the LCD (Liquid Crystal Display) frame inside the reader / writer device is a metal part), if the distance between the metal part and the loop antenna is short, The magnetic field output from the loop antenna is obstructed by the metal parts. For example, in the technique of Patent Document 1, a liquid crystal panel and a loop antenna are configured inside the reader / writer device. Here, when the frame of the liquid crystal panel is a metal part, the distance between the metal part and the loop antenna is short. In this case, the magnetic field output from the loop antenna is hindered by the metal parts.

For example, when a loop antenna is incorporated as a module in the reader / writer device, the distance between the loop antenna in the RFID tag and the loop antenna of the reader / writer device is increased, and communication loss increases.

For the above reasons, there is a problem that the communication range of the reader / writer device cannot be widened.

  An object of the present invention is to realize a wide communication range of a reader / writer device.

  The reader / writer device according to claim 1 is a display unit, an upper case for holding the display unit, a loop disposed on an outer surface of the upper case and wound around the display unit. An antenna.

  According to a second aspect of the present invention, in the reader / writer device according to the first aspect, the loop antenna is disposed on the outer surface of the upper case and is wound around the display unit.

  According to a third aspect of the present invention, in the reader / writer device according to the first or second aspect, a frame-shaped cover is provided, and the frame-shaped cover covers the loop antenna.

  According to a fourth aspect of the present invention, in the reader / writer device according to any one of the first to third aspects, the loop antenna and a sub-board for connecting the loop antenna to a main board are electrically connected. A contact connector for connection is provided.

  According to a fifth aspect of the present invention, in the reader / writer device according to any one of the first to fourth aspects, the coordinate updating operation of the touch panel is stopped during the communication operation between the touch panel and the loop antenna. And comprising.

  According to a sixth aspect of the present invention, in the reader / writer device according to any one of the first to fifth aspects, a middle case to which the display unit can be attached and a sub-connect for connecting the loop antenna to a main board. A substrate, and the sub-board includes a trimmer for adjusting a gain characteristic of the loop antenna, and the middle case is for adjusting the trimmer in a state where the middle case is attached to the upper case. Provide notches or holes.

  According to a seventh aspect of the present invention, in the reader / writer device according to any one of the third to sixth aspects, the loop antenna and the frame-shaped cover are integrally molded.

  The invention according to an eighth aspect is the reader / writer device according to any one of the first to seventh aspects, further comprising a magnetic sheet between the loop antenna and the upper case.

  According to the present invention, it is possible to widen the communication range of the reader / writer device.

It is the schematic of the handy terminal of embodiment which concerns on this invention. It is a figure which shows the state which removed the bezel from the handy terminal. It is a figure which shows the internal structure of a handy terminal. It is a figure which shows sectional drawing of a handy terminal. It is a figure which shows the state before attaching sub PCB to an upper case. It is a figure which shows the state after attaching sub PCB to an upper case. It is a flowchart which shows the flow of RFID communication processing. It is a figure which shows a state when sub PCB provided with the trimmer capacitor is attached to the upper cover. It is a figure which shows the matching circuit of sub PCB. It is a figure which shows the state in which the lower case and main PCB are not attached to the upper case. It is a figure which shows the structure which integrally molded the loop antenna and the bezel. It is a figure which shows the structure provided with the magnetic material sheet between the loop antenna and the upper cover.

  Hereinafter, an example of an embodiment according to the present invention will be described in detail with reference to the accompanying drawings. However, the scope of the invention is not limited to the illustrated examples.

  Embodiments according to the present invention will be described with reference to FIGS. First, a schematic diagram of a handy terminal 10 as a reader / writer device having a reader / writer function according to the present invention will be described with reference to FIG.

  The handy terminal 10 of the present embodiment is used in stores such as supermarkets, convenience stores, and private stores. The handy terminal 10 has an input and storage function for various information, an information reading function for an RFID tag, and a barcode reading function for reading barcode information attached to a product. For example, when reading the information of the RFID tag with the handy terminal 10, the RFID tag information is read by positioning the RFID tag near the display unit 14 shown in FIG. Here, the handy terminal 10 may be any portable terminal device having at least an RFID tag reading function. In addition, the handy terminal 10 may be used for purposes other than store use.

  As shown in FIG. 1, the handy terminal 10 includes a bezel 1 and a case 2. The bezel 1 is a cover (frame-shaped cover) for the display unit 14. The case 2 is a resin case and includes an upper case 2A and a lower case 2B. The upper case 2A is a case for holding each component (the display unit 14 and the like) of the handy terminal 10. The handy terminal 10 includes a display unit 14, a touch panel 16, and a key input unit 12A on the front. The handy terminal 10 includes a scanner unit 18 at the tip.

  The display unit 14 includes an LCD (Liquid Crystal Display) and displays various screens. The touch panel 16 is configured integrally with the display unit 14. The key input unit 12A has various function keys, character / number input keys, cursor keys, and the like, and accepts input of determination of various functions, characters / numbers, movements, and the like when the user presses each key. The scanner unit 18 receives reflected light reflected from a bar code or a two-dimensional code, and reads bar code information.

  FIG. 2 shows a state in which the bezel 1 is removed from the handy terminal 10. As shown in FIG. 2, a loop-shaped RF antenna (hereinafter referred to as a loop antenna 21) is disposed on the outer surface of the upper case 2A, and the loop antenna 21 is wound around the display unit 14 (touch panel 16). Is (formed as a winding). The winding shape of the loop antenna 21 will be described later with reference to FIG.

  Specifically, the loop antenna 21 is a coil antenna for reading information from and reading information from an RFID tag, and is an antenna configured by FPC (Flexible Printed Circuits) including a coiled copper wire. .

  Next, the internal functional configuration of the handy terminal 10 will be described with reference to FIG. As shown in FIG. 3, the handy terminal 10 includes a CPU 11 as a control unit, an operation unit 12, a RAM (Random Access Memory) 13, a display unit 14, a ROM (Read Only Memory) 15, and a touch panel 16. , A flash memory 17, a scanner unit 18, an I / F (Inter Face) unit 19, a reader / writer unit 20, a loop antenna 21, and a power supply unit 22, and each unit excluding the power supply unit 22 is a bus 23. Connected through.

  The CPU 11 controls each part of the handy terminal 10. The CPU 11 reads a designated program from among the system programs and application programs stored in the ROM 15, expands it in the RAM 13, and executes various processes in cooperation with the program expanded in the RAM 13.

  The operation unit 12 includes a keypad including various keys 12A. The operation unit 12 receives an operation input of each key on the keypad, and outputs operation information corresponding to the operation input to the CPU 11.

  The RAM 13 is a volatile memory that temporarily stores information. The RAM 13 has a work area for storing various data and programs.

  The display unit 14 is configured by an LCD or the like. The display unit 14 performs various displays according to display information input from the CPU 11. Further, the frame of the display unit 14 is made of a metal part for improving resistance.

  The ROM 15 is a memory in which various programs and various data are stored in advance for reading only. The ROM 15 stores an RFID communication program 151 described later.

  The touch panel 16 is provided, for example, on the display screen of the display unit 14 or on the inner side of the display screen, and the contact position of the user's finger or touch pen on the display screen by a method such as an electromagnetic induction method, a magnetostriction method, or a pressure sensitive method. XY coordinates are detected, and the coordinate information is output to the CPU 11.

  The flash memory 17 is a semiconductor memory that stores information in a readable and writable manner. The scanner unit 18 includes a light emitting unit such as a laser beam, a light receiving unit, a gain circuit, a binarization circuit, and the like. In the scanner unit 18, the light emitted from the light emitting unit is irradiated onto the barcode, the reflected light is received by the light receiving unit and converted into an electric signal, the electric signal is amplified by the gain circuit, and the binarization circuit Converted to black and white barcode image data. In this way, the scanner unit 18 reads the barcode image and outputs the barcode image data to the CPU 11.

  The I / F unit 19 is a connection unit that can be connected to a predetermined device and mediates communication with the connected device.

  The reader / writer unit 20 has a loop antenna 21, and reads information from the RFID tag via the loop antenna 21 according to an instruction from the CPU 11 to read / write. More specifically, the reader / writer unit 20 modulates the transmission signal input from the CPU 11 and inputs the modulated signal to the loop antenna 21 in a state where the RFID tag is disposed within the readable range of the loop antenna 21. Then, a current is generated in the loop antenna in the RFID tag via the electromagnetic field generated from the loop antenna 21, and the information is received on the RFID tag side by demodulating and encoding the electric signal. Then, information reading or information writing in the memory in the RFID tag is performed. In addition, a current flows through the loop antenna 21 via an electromagnetic field generated in the loop antenna 21 in response to a signal of transmission information such as information read from the memory from the RFID tag, and the electric signal is modulated by the reader / writer unit 20. As a result, the information is received on the reader / writer unit 20 side.

  The power source unit 22 is a power source that supplies power to each unit of the handy terminal 10. The power supply unit 22 is a secondary battery such as a lithium battery, for example.

  FIG. 4 shows a schematic sectional structure of the handy terminal 10. The cross-sectional schematic structure shown in FIG. 4 is a structure showing the AA cross section shown in FIG. As shown in FIG. 4, the handy terminal 10 includes a lower case 2B, a main PCB (Printed Circuit Board) 3 as a main substrate, a middle case 4, a display unit (LCD) 14, an impact absorbing sheet + spacer unit. 5, touch panel 16, FPC + connector portion 6, sub PCB 7 as a sub board, contact connector 8 as a contact connector, screw 9, upper case 2 </ b> A, loop antenna 21, and bezel 1. Configured.

  The main PCB 3 is a printed circuit board for controlling each part of the handy terminal 10. On the main PCB 3, a CPU (Central Processing Unit), a matching circuit for the loop antenna 21, and the like are mounted. The middle case 4 is a resin case and is disposed between the display unit 14 and the main PCB 3. The shock absorbing sheet + spacer portion 5 is a shock absorbing portion for preventing liquid crystal cracking.

  The FPC + connector portion 6 electrically connects the main PCB 3 and the sub PCB 7. The sub PCB 7 is a substrate for connecting (electrically connecting) the loop antenna 21 to the main PCB 3. That is, the loop antenna 21 and the main PCB 3 are connected via the sub PCB 7.

  Further, the PCB 7 has peripheral functions of the handy terminal 10 (LED (Light Emitting Diode) light emitting function, speaker (not shown) audio output function, etc.). The contact connector 8 is a contact spring type connector.

  The loop antenna 21 is disposed on the outer surface of the upper case 2A and is wound around the display unit 14 (touch panel 16). Further, a part of the loop antenna 21 is wired on the inner surface of the upper case 2A through a gap formed in the upper case 2A. Further, the loop antenna 21 and the upper case 2A are bonded by a double-sided tape (not shown). The loop antenna 21 is covered with the bezel 1.

  Next, attachment of the sub PCB 7 and the upper case 2A will be described with reference to FIGS. FIG. 5 is a view seen from the direction B in FIG. 4 and shows a state before the sub PCB 7 is attached (fixed) to the upper case 2A. Specifically, FIG. 5 shows the case where the lower case 2B, the main PCB 3, the display unit 14, the shock absorbing sheet + spacer unit 5, and the touch panel 16 are not attached to the upper case 2A. It is the figure which showed the state before attaching.

  As shown in FIG. 5, a contact connector 8 and an FPC + connector portion 6 are provided on the sub PCB 7. The upper case 2 </ b> A is provided with a connection portion 31 that is connected to the contact connector 8. The connection part 31 is electrically connected to the loop antenna 21.

  FIG. 6 is a view showing a state after the sub PCB 7 is attached (fixed) to the upper case 2A. The sub PCB 7 and the upper case 2 </ b> A are fixed by stopping the screws 9. As shown in FIG. 6, when the sub PCB 7 and the upper case 2 </ b> A are fixed with screws 9, the connection portion 31 and the contact connector of the upper case 2 </ b> A shown in FIG. 8 is contacted and connected. Thereby, the loop antenna 21 and the sub PCB 7 are electrically connected.

  Next, a case where the handy terminal 10 executes RFID communication processing will be described with reference to FIG. FIG. 7 shows the flow of RFID communication processing. The RFID process is a process of stopping the coordinate update of the touch panel 16 during RFID communication.

  It is assumed that touch panel coordinate update processing has been executed in advance in response to an operation input from the user via the operation unit 12. The touch panel coordinate update process is a process of updating the touched position (coordinate value on the touch panel 16) when the user's finger touches the touch panel 16.

  In the handy terminal 10, for example, in cooperation with the CPU 11, the RFID communication program 151 that is read from the ROM 15 and appropriately expanded in the RAM 13 is triggered by the user's pressing input of the RFID communication processing execution instruction. RFID communication processing is executed.

  First, the touch panel coordinate update process is stopped (step S11). Then, RFID communication is executed (step S12). That is, communication using a magnetic field is performed between the handy terminal 10 and the RFID tag.

  After execution of step S12, it is determined whether or not the RFID communication is finished (step S13). Specifically, for example, the determination of this step is performed based on whether or not a predetermined time has elapsed since the end of transmission / reception of information.

  If it is determined in step S13 that the RFID communication has not ended (step S13; NO), the process proceeds to step S12. If it is determined in step S13 that the RFID communication has ended (step S13; YES), the touch panel coordinate update process is resumed (step S14). After execution of step S14, the RFID communication process is terminated.

  As described above, according to the present embodiment, since the loop antenna 21 is arranged on the outer surface of the upper case 2A, the distance between the loop antenna 21 and the loop antenna of the RFID tag can be further shortened, thereby reducing communication loss. be able to. Moreover, since the loop antenna 21 is disposed on the outer surface of the upper case 2A, the loop area of the loop antenna 21 can be increased. Moreover, since the loop antenna 21 is disposed at a position away from the metal component (the frame of the display unit 14) via the upper case 2A or the like, it is possible to prevent the magnetic field from being obstructed by the metal component. For this reason, the wide communication range of the handy terminal 10 can be realized.

  Moreover, the loop antenna 21 can be protected by covering the loop antenna 21 with the bezel 1.

  Further, for example, in the case of a configuration in which a plug-in connector is used instead of the contact connector 8, an operation of inserting the connector and further screwing it is necessary. However, with the configuration of the contact connector 8, the loop antenna 21 and the sub PCB 7 can be electrically connected only by screwing, and there is no need to perform the work of inserting the connector. For this reason, a work process can be omitted and the efficiency of assembly can be improved (work load is reduced).

  In addition, since the coordinate update operation of the touch panel is stopped during RFID communication, it is possible to prevent malfunction caused by the RFID tag or the user's finger accidentally touching the touch panel 16 when the user holds the RFID tag. .

(First modification)
A first modification of the above embodiment will be described with reference to FIGS. In the following, the same parts as those in the above embodiment are denoted by the same reference numerals, and the detailed description thereof is used to describe different parts.

  The handy terminal 10 </ b> A of this modification is configured such that the middle case 4 is changed to the middle case 4 </ b> A and a trimmer capacitor 7 </ b> A as a trimmer is provided on the sub PCB 7.

  FIG. 8 is a view as seen from the B direction of FIG. 4, in which the lower case 2B, the main PCB 3, the display unit 14, the shock absorbing sheet + spacer unit 5, and the touch panel 16 are not attached to the upper case 2A. FIG. 5 is a view showing a state where the sub PCB 7 is attached to the upper case 2A.

  As shown in FIG. 8, in this modification, a trimmer capacitor 7 </ b> A is provided on the sub PCB 7. The trimmer capacitor 7A is a trimmer for adjusting the capacitor capacity in the matching circuit M for adjusting the antenna gain on the sub PCB 7.

  FIG. 9 shows a matching circuit M for adjusting the antenna gain on the sub PCB 7. For example, when the trimmer capacitor 7A is adjusted by a driver or the like by the manufacturer, the capacitance of the capacitor C in the matching circuit M for adjusting the antenna gain is adjusted. When the capacitance of the capacitor C is adjusted, the gain characteristic of the loop antenna 21 is adjusted. The loop antenna 21 is formed on the antenna FPC in a winding shape as shown in FIG. 9, for example.

  Next, the middle case 4A of this modification will be described with reference to FIG. FIG. 10 is a view as seen from the direction B in FIG. 4 and shows a state where the lower case 2B and the main PCB 3 are not attached to the upper case 2A. Here, the display unit 14 (two-dot chain line in FIG. 10) is attached to the middle case 4A. The main PCB 3 is mounted on the middle case 4 (on the side opposite to the side on which the display unit 14 is mounted).

  As shown in FIG. 10, the middle case 4A has a notch C. The cutout C enables the manufacturer to adjust the trimmer capacitor 7A on the sub PCB 7 with the lower case 2B removed from the handy terminal 10A. Note that the cutout C may have a hole shape.

  As described above, according to the present modification, the trimmer capacitor 7A can be adjusted only by removing the lower case 2B by the configuration in which the middle case 4A has the notch C and the sub PCB 7 includes the trimmer capacitor 7A. For this reason, even in the final assembly process of the product, the manufacturer can adjust the trimmer capacitor 7A. Even in the process of attaching the sub PCB 7, the manufacturer can adjust the trimmer capacitor 7A. For this reason, the freedom degree of adjustment of the gain characteristic of the loop antenna 21 can be improved.

  Further, by adjusting the trimmer capacitor 7A in the final assembly process of the product, the gain of the loop antenna 21 is adjusted (adjustment of the capacitor capacity of the matching circuit M) with the display unit 14 (with a metal part frame) attached. Work can be done. That is, since the gain of the loop antenna 21 can be adjusted in the same state as the final product, it is not necessary to adjust the gain of the loop antenna 21 in anticipation of the state in which the display unit 14 is attached in advance. For this reason, the gain of the loop antenna 21 can be adjusted accurately.

(Second modification)
A second modification will be described with reference to FIG. In the following, the same parts as those in the above embodiment are denoted by the same reference numerals, and the detailed description thereof is used to describe different parts.

  The handy terminal 10 </ b> B of the present modification is changed to a configuration in which the bezel 1 and the loop antenna 21 of the handy terminal 10 are integrally molded (molded). FIG. 11 is a cross-sectional view showing the bezel 1A and the loop antenna 21 of the handy terminal 10B of the present modification. As shown in FIG. 11, the bezel 1A, the loop antenna 21 and the connection cable 32 are molded.

  As described above, according to the present modification, the bezel 1A and the loop antenna 21 are integrally molded, so that it is not necessary to separately attach the loop antenna 21 and the bezel 1A to the upper case 2A. For this reason, it is only necessary to attach the bezel 1A to the upper case 2A, and the burden of assembly work can be reduced.

(Third Modification)
A third modification of the above embodiment will be described with reference to FIG. In the following, the same parts as those in the above embodiment are denoted by the same reference numerals, and the detailed description thereof is used to describe different parts.

  The handy terminal 10 </ b> C of the present modification is changed to a configuration in which a high magnetic material magnetic sheet 33 is added to the handy terminal 10. FIG. 12 is a view showing the bezel 1, the loop antenna 21 and the magnetic material sheet 33 of the handy terminal 10C of the present modification. As shown in FIG. 12, the handy terminal 10C includes a magnetic sheet 33 between the loop antenna 21 and the upper case 2A. The magnetic material sheet 33 is made of a magnetic material such as iron oxide, chromium oxide, cobalt, or ferrite. The magnetic sheet 33 has a characteristic that allows easy passage of a magnetic field output from the loop antenna 21.

  As described above, according to the present modification, the magnetic sheet 33 has an effect of increasing the distance between the loop antenna 21 and the metal part (the frame of the display unit 14) due to the characteristic that the magnetic sheet 33 can easily pass through the magnetic field. For example, when a configuration including the magnetic sheet 33 is compared with a configuration not including the magnetic sheet 33, the configuration including the magnetic sheet 33 has an effect of approximately 10 times the thickness (that is, the magnetic sheet 33). The effect of separating the distance between the loop antenna 21 and the metal part by about 10 times as compared with the case without the above). For this reason, providing the magnetic sheet 33 has an effect of increasing the distance between the loop antenna 21 and the metal part, and further prevents the magnetic field output from the loop antenna 21 from being obstructed by the metal part. be able to.

  Note that the descriptions in the above-described embodiments and modifications are examples of the reader / writer device according to the present invention, and the present invention is not limited to this. For example, it is good also as a structure which combines at least 2 among the said embodiment and the said modification.

  In the above embodiment and each modified example, the handy terminal is used as the reader / writer device. However, other portable terminal devices such as a PDA and a mobile phone may be used.

  In the above-described embodiment, the RFID communication process is executed with the trigger input of the execution instruction of the RFID communication process from the user as a trigger. However, the present invention is not limited to this. For example, the RFID communication process may be executed periodically.

  In addition, it goes without saying that the detailed configuration and detailed operation of each component of the reader / writer device in the above-described embodiment and each modification can be appropriately changed without departing from the spirit of the present invention.

10, 10A, 10B, 10C Handy terminal 1 Bezel 2 Case 2A Upper case 2B Lower case 14 Display unit 12A Key input unit 11 CPU
12 Operation unit 13 RAM
14 Display 15 ROM
16 Touch Panel 17 Flash Memory 18 Scanner Unit 19 I / F Unit 20 Reader / Writer Unit 21 Loop Antenna 22 Power Supply Unit 23 Bus 3 Main PCB
4, 4A Middle case 5 Shock absorbing sheet + spacer part 6 FPC + connector part 7 Sub PCB
8 Contact connector 9 Screw 7A Trimmer capacitor M Matching circuit

Claims (8)

A display unit;
An upper case for holding the display unit;
A loop antenna disposed on the outer surface of the upper case and provided around the display unit;
A reader / writer device comprising:   The reader / writer device according to claim 1, wherein the loop antenna is disposed on an outer surface of the upper case and wound around the display unit. With a frame-shaped cover,
The frame-shaped cover is
The reader / writer device according to claim 1, wherein the reader / writer device covers the loop antenna.   4. The reader / writer device according to claim 1, further comprising a contact connector for electrically connecting the loop antenna and a sub-board for connecting the loop antenna to a main board. 5. A touch panel;
A control unit that stops the coordinate update operation of the touch panel during the communication operation of the loop antenna;
The reader / writer device according to any one of claims 1 to 4, further comprising: A middle case to which the display unit can be attached;
A sub-board for connecting the loop antenna to the main board,
The sub-board is
A trimmer for adjusting the gain characteristic of the loop antenna;
The middle case is
The reader / writer device according to any one of claims 1 to 5, further comprising a notch or a hole for adjusting the trimmer in a state in which the middle case is attached to the upper case.   The reader / writer device according to claim 3, wherein the loop antenna and the frame-shaped cover are integrally molded.   The reader / writer device according to any one of claims 1 to 7, further comprising a magnetic sheet between the loop antenna and the upper case.

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