JP4374346B2 - IC tag affixing sheet for optical recording media - Google Patents

Description

The present invention relates to a sheet for attaching an IC tag to a disk-shaped optical recording medium such as a CD or a DVD, and particularly to provide a sheet suitable for a library lending management system.

  Recently, attention has been focused on IC tags. An IC tag is a small device that combines an ultra-small IC (integrated circuit) chip and an antenna for wireless communication, and uses a wireless communication device called a reader / writer to write data to the IC chip, The data can be read.

  If ID information (identification information) unique to each IC chip is recorded and attached to each product, literally “single product management” is possible, and therefore, introduction is widely studied mainly in the distribution field. Conventionally, barcodes have been widely used in the distribution field, but IC tags can read and write data in a non-contact / remote manner and increase the amount of data that can be stored. It is said that it can be applied to a wider range of applications.

  Library lending management systems are becoming popular as management systems using IC tags. 2. Description of the Related Art Conventionally, for the purpose of rationalizing document management, a library for lending management of barcode-type (optical code reading) and OCR (optical character recognition) -type document has been introduced in many libraries. A system that uses barcodes can save a lot of labor and reliability, but it is necessary to read the documents one by one with a scanner, and the information of multiple documents can be read at once. It takes time and effort.

  In order to solve the above problems and to further streamline the management of books, in recent years, IC tags that record and register book information are affixed to books and registered on the IC chip by a reader / writer. Reading information such as numbers is performed.

  When a user borrows a book, when the book is placed on a reader / writer, the information on the IC tag attached to the book is read and lent out, and the information on the lent is written on the IC tag. When borrowing a plurality of books, processing must be performed for all of the plurality of books. If any one of a plurality of documents cannot be read at the time of lending, it is necessary to manually check which document information could not be read one by one. For this reason, the library lending management system is required to be able to reliably communicate with the IC tags of all books.

  By the way, there are an increasing number of libraries that lend out music CDs and movie DVDs along with books. An IC tag is affixed to manage CDs and DVDs (hereinafter collectively referred to as “recording medium”), but conventionally, an IC tag is usually affixed to the case of a recording medium. No IC tag was directly attached to the medium. The antenna of the reader / writer and the antenna of the IC tag are electromagnetically coupled to supply power to the IC tag and perform communication. However, when the IC tag is directly attached to the recording medium, the recording surface of the recording medium (conductor) This is because the electromagnetic coupling is not performed satisfactorily due to the influence of the aluminum thin film), and communication cannot be performed.

  However, when an IC tag is affixed to the case, correct management cannot be performed when the case is empty or the case is misplaced. In order to perform proper management in consideration of such a situation, it is necessary to collate the case of the recording medium with the contents one by one, which takes a lot of trouble. With this, the meaning of introducing the IC tag is lost. Therefore, it is required to attach the IC tag directly to the recording medium.

[Patent Document 1] JP-A-11-250494

  Patent Document 1 discloses that a non-contact IC chip is integrated with a disk-shaped recording medium. An electromagnetic coupling type non-contact IC chip is embedded or pasted in the vicinity of the central hole of a CD-ROM as a recording medium, and an antenna is embedded in or pasted on the CD-ROM so as to go around the central hole. In this, information for identifying each medium and information for confirming the authenticity of the recorded contents of the CD-ROM are recorded.

  The IC tag attached to the recording medium must be capable of transmitting and receiving power and signals by an electromagnetic coupling method, read-only or capable of writing and reading, and hinders rotation when it does not protrude from the surface of the recording medium. In addition to the above conditions, it is necessary to satisfy the following conditions in order to conform to the library lending management system.

(1) In the library lending management system, the distance between the reader / writer and the reader / writer may be about several tens of centimeters. In addition, since the general gate interval for detecting carry-out is 90 cm, a reading distance of about 45 cm, which is half of that, is preferable (the communication distance of the IC tag is remarkably shortened by the influence of the recording surface of the recording medium, at least in the library) It has been said that it is impossible to use an IC tag directly attached to a recording medium in a rental management system).

(2) Since several books and several CDs may be lent out at the same time, even if many books or CDs are stacked on the reader / writer, all books and CD IC tags Must be able to communicate with.

(3) It must be applicable to all recording media handled by the library. Since IC tags are affixed to recording media in libraries (not affixed in the manufacturing process of recording media, but affixed afterwards), IC tags must be usable on any recording media. The inventor has found that the communication performance of an IC tag varies greatly depending on the type of recording medium. The standard specifies the size and material of the recording medium, but in reality, it seems to be affected by the printing state (printing thickness, ink type, etc.) on the surface of the recording medium (especially including iron) The effect of ink seems to be great).

  An IC tag provided with an antenna so as to circulate around the center hole of the CD-ROM disclosed in Patent Document 1 is not affected by the recording surface of the aluminum thin film that does not exist. Since the antenna provided around the antenna has a small diameter and its communication capability is low, communication cannot be performed at a distance (about 5 cm at most). Therefore, the conditions (1) and (2) cannot be satisfied. In addition, in paragraph 0018 of Patent Document 1, it is described that the antenna is arranged on the outermost periphery of the recording medium. However, in this paragraph, a finger or a member of a CD-ROM drive device may come into contact with the outer periphery. It is also stated that since there are many, there are many opportunities to damage the IC chip, which is not preferable in practice. This is because Patent Document 1 is concerned with providing an antenna in a portion other than the recording surface of the aluminum thin film, that is, a portion other than the information recording area, so that the antenna is attached to the edge of the disk of the recording medium having a width of only about 1 mm. This is because it must be provided. In Patent Document 1, in order to avoid the influence of the recording surface of the aluminum thin film, the basic concept is to provide an antenna in a portion where the recording surface does not exist.

  Further, the invention disclosed in Patent Document 1 cannot satisfy the condition (3). Referring to the entire description of Patent Document 1, the present invention is intended to provide an IC tag in the manufacturing process of the recording medium, and does not seem to attach the IC tag after the product is shipped. Patent Document 1 does not apply to various types of recording media, but ignores the effect of the printing surface of the recording media, which is important when IC tags are attached later, and is used in a library lending management system. It is not possible.

  An object of the present invention is to provide an IC tag attaching sheet for a recording medium that satisfies the above conditions (1) to (3) and is particularly suitable for a library lending management system.

The present invention provides a disk-like thin plate-like base portion having the same shape as that of a disk-like optical recording medium such as a CD or DVD that includes a recording area for recording information therein, and a loop shape provided in the base portion. And an IC chip that performs non-contact communication through the antenna,
In a state where the sheet is attached to the optical recording medium,
The antenna is provided on the base so as to be positioned on a recording area of the optical recording medium;
The resonance frequency of the antenna before being attached to the optical recording medium is set higher than the use frequency of the IC chip.
Further, the antenna includes a plurality of arc-shaped circumferential portions located on the circumference of the optical recording medium, and a plurality of non-circumferential portions located on the inner side of the circumference of the optical recording medium, The circumferential portions are arranged symmetrically with respect to the rotation center of the optical recording medium, and the non-circular portions are arranged symmetrically.
Each of the plurality of circumferential portions is a portion corresponding to ¼ of the circumference, and each of the plurality of non-circumferential portions is a portion corresponding to ¼ of the circumference, respectively. It is the part of the shape bent to
Alternatively, each of the plurality of circumferential portions is a portion corresponding to 1/6 of the circumference, and each of the plurality of non-circumferential portions ties two opposite ends of the plurality of circumferential portions, respectively. There are two straight parts.

  It is preferable that the number of turns and the interval of the conductive wire of the antenna are set so that the variation in the communication distance of the antenna is reduced when the antenna is attached to a plurality of types of recording media.

A preferred example of the number of turns and spacing of the conductor wire of the antenna is as follows.
When using a CD / DVD having a use frequency of 13.56 MHz and a recording medium of 12 cm in diameter as a recording medium, the number of turns of the conducting wire is 4, and the spacing between the conducting wires is 0.35 mm or 0.45 mm. However, the diameter of the antenna is 110 mm, and the cross-sectional diameter φ of the conductor is 0.11 mm.

  The antenna includes a plurality of arc-shaped circumferential portions located on the circumference of the recording medium, and a plurality of non-circular portions located on the inner side of the recording medium. The circumferential portions may be arranged symmetrically with respect to the rotation center, and the non-circular portions may be arranged symmetrically.

  It is preferable that the antennas have different shapes so that the antennas of the recording media do not interfere with each other when a plurality of recording media with IC tags attached are stacked. If the antenna is provided with a non-circumferential portion, the shape of the non-circumferential portion can be arbitrarily set, and various shapes can be realized.

  Furthermore, a counterweight provided at a position symmetrical to the position of the IC chip with respect to the rotation center of the recording medium may be provided.

A storage medium according to the present invention performs non-contact communication through a disk-shaped recording medium including a recording area for recording information therein, a loop-shaped antenna provided on the surface of the recording medium, and the antenna. An IC chip,
The antenna is formed of a conducting wire having a substantially circular or substantially square cross section, and the antenna is positioned on a recording area of the recording medium.

  According to the present invention, the antenna is formed of a conducting wire having a substantially circular or substantially square cross section, and the antenna is disposed along the circumference of the recording medium, so that it has succeeded in extending the communication distance to a practical level. Moreover, by appropriately selecting the number of windings and the interval between the conductors constituting the antenna, the antenna can be used by being attached to various recording media.

An IC tag attaching sheet for a recording medium according to an embodiment of the present invention and a recording medium attached with the same will be described with reference to the drawings.
1A and 1B are diagrams showing an IC tag attaching sheet for a recording medium according to an embodiment of the present invention. FIG. 1A is a plan view, and FIG. 1B is a cross-sectional view taken along line AA in the plan view. FIG. In addition, sectional drawing is a schematic diagram and each thickness does not show the correct scale. In addition, a planar and linear state is shown on the assumption that no distortion or deflection occurs. In FIG. 1, reference numeral 1 denotes a recording medium IC tag attaching sheet according to an embodiment of the present invention. The IC tag affixing sheet 1 for a recording medium has a disc-shaped sheet (base) 10 that is the same shape as a recording medium such as a CD and is slightly smaller than that, and a little inside the outer edge of the sheet 10 (eg, about 2.5 mm inside). An antenna 101 provided along the circumference, an IC chip 102 that communicates with the outside in a non-contact manner through the antenna 101, a connection conductor 103 for connecting the antenna 101 to the IC chip 102, and a rotation center of the recording medium On the other hand, a counterweight (balance weight) 104 is provided at a symmetrical position of the IC chip 102 to balance the rotation. On the lower surface of the IC tag sticking sheet 1 for recording medium, there is a double-sided tape 11 (for example, thickness = about 0.05 mm) for sticking the sheet 1 to the recording medium, and a separator 12 for protecting the adhesive surface of the double-sided tape 11. Is provided. The separator 12 is peeled off, and the recording medium IC tag attaching sheet 1 is attached to the recording medium.

  The sheet 10 serves as a base to which the antenna 101 and the IC chip 102 are attached, and the shape thereof is adapted to the recording medium. Specifically, it is circular. If the diameter of the sheet 10 is equal to or larger than that of the recording medium, the sheet 10 may interfere with the rotational driving of the recording medium. Therefore, the diameter of the sheet 10 is slightly smaller than the recording medium (for example, the diameter of the recording medium = About 120 mm, the diameter of the sheet 10 = about 115 mm). An inner hole having a larger diameter than the inner hole is provided inside the sheet 10 so as not to block the inner hole for rotationally driving the recording medium. In FIG. 1, 10 a indicates the outer edge of the sheet 10, and 10 b indicates the edge of the inner hole of the sheet 10.

  The sheet 10 is provided with an opening for accommodating the IC chip 102 and the counterweight 104. For this reason, the surface of the sheet 10 is flat. If the IC chip 102 is relatively thin, the IC chip 102 does not protrude on the sheet 10, but even if it protrudes somewhat, there is no practical problem (for example, the thickness of the sheet 10 made of resin (polycarbonate) = about 0. 0). In the case of an IC chip having a main body height = 0.15 mm and a mounting portion thickness = 0.08 mm, it does not protrude on the sheet 10, but the main body height = 0.3 mm and the mounting portion thickness = 0.08 mm. In the case of the IC chip, it protrudes somewhat).

  The antenna 101 (eg, antenna diameter = about 110 mm) is formed by winding a conducting wire having a substantially circular cross section (may be a substantially square or a substantially regular polygon) a plurality of times. Although it is impossible to communicate when the cross section is a thin plate or foil like a printed wiring, it has been found that communication is possible as will be described later if a conductor having a circular cross section is used. In addition to the circular shape, it is estimated that a regular polygonal shape or a square shape can be used. The resonance frequency of the antenna 101 is set higher than the use frequency of the IC chip 102. With this setting, when the recording medium IC tag attaching sheet 1 is attached to the recording medium, the resonance frequency becomes low and matches the operating frequency. As shown in FIG. 1A, by arranging the antenna 101 in a circle along the outer edge of the sheet 10, it is possible to maximize the diameter of the antenna 101 and increase its gain. However, if at least a part of the antenna 101 has a shape as shown in FIG. 1A (eg, see FIGS. 10 and 11), a necessary gain can be obtained.

FIG. 2A shows a detailed sectional view of the antenna 101 portion. The antenna 101 is composed of four conducting wires 101-1 to 101-4 arranged substantially concentrically. The diameter of the conducting wire is about 0.11. The four conducting wires 101-1 to 101-4 are arranged at a constant interval (pitch) P. It is important to configure the antenna 101 with a thin conducting wire in order to satisfy the above conditions (1) to (3). When the thickness is small with respect to the conductor width (typically when the conductor is printed or etched) as indicated by reference numerals 101'-1 and 101'-2 in FIG. In this state, it was not possible to communicate with the IC tag. This is because, when formed by etching or the like, it is difficult to increase the thickness of the conductor, and the cross-sectional area cannot be increased. Even if the thickness is excessively large, one surface (for example, a side surface) of the conductor is thinned, and the cross-sectional area cannot be increased as in a conducting wire. Therefore, it is presumed that the resistance value becomes larger than the inductance, and the coil characteristics deteriorate.
On the other hand, if the antenna is constituted by a conducting wire as shown in FIG. 2A, the antenna 101 and the IC chip 102 can be provided in a region where the recording surface of the recording medium is present. Patent Document 1 discloses that the antenna 101 and the IC chip 102 are provided exclusively in a region where the recording surface does not exist. However, according to the embodiment of the present invention, such a restriction is not necessary.

  FIG. 2B shows a detailed sectional view of a portion of the IC chip 102. Although depending on the type of the IC chip 102, the IC chip 102 includes a main body 102a and a mounting portion 102b as a base thereof. The IC chip 102 is attached to the sheet 10 with the attachment portion 102b. The main body 102a is accommodated in the opening provided in the sheet 10 described above. FIG. 2D shows an example of a plan view of the IC chip 102. In this example, the main body 102a is provided with attachment portions 102b that also serve as connection terminals at both ends. The antenna 101 is connected to these terminals. The counterweight 104 is also the same as that shown in FIG.

  3A and 3B are views showing a state in which the IC tag attaching sheet 1 for recording medium is attached to the recording medium. FIG. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along line AA in the plan view. FIG. As apparent from FIG. 3A, the recording medium IC tag attaching sheet 1 does not protrude from the recording medium. Therefore, if the thickness of the sheet 1 is within the range allowed by the standard of the recording medium, the original function of the recording medium is not impaired. The antenna 101 and the IC chip are provided on the recording surface (recording area) 21 of the recording medium as shown in FIG.

Next, a specific example of the embodiment of the present invention will be described.
4 to 8 are actual measurement data obtained by measuring the resonance frequency and the communication distance by changing the number of windings of the antenna 101 and the interval (pitch) thereof. A dip meter is used to measure the resonance frequency. The dip meter has an oscillation circuit that displays the oscillation energy on the meter. Move the dip meter coil close to the coil of the resonance circuit to be measured, and turn the dial of the measuring instrument to change the oscillation frequency little by little. The needle goes down. This is used to measure the frequency of the resonant circuit.

  FIG. 4 shows the characteristics when the number of turns = 4 and the pitch = 0.35 mm. FIG. 4A is a graph showing the resonance frequency and the communication distance. The vertical scale on the right side of the graph indicates frequency (unit: MHz), and the vertical scale on the left side indicates communication distance (unit: mm) (the same applies to the graphs in FIG. 5 and subsequent figures). The horizontal axis is the number of the recording medium to which the IC tag to be measured is attached. In FIG. 4, measurement is performed on 10 recording media. The ten recording media in FIG. 4 are all the same type. On the other hand, the data shown in FIG. 5 and after are measured for different types of recording media. FIG. 4B shows the measurement data. The graph of FIG. 4A is a graph display of the data of FIG. 4B (the same applies hereinafter).

The following can be understood from FIG.
-Since all are the same type of recording medium, there is little variation in the resonance frequency and communication distance for each recording medium.
The resonance frequency is about 14.5 MHz and the communication distance is about 260 mm.

FIG. 5 shows the characteristics of different types of recording media with the number of turns = 4 and the pitch = 0.35 mm. The following can be seen from FIG.
・ Because it is a different type of recording medium, the variation in resonance frequency and communication distance for each recording medium has increased.
The resonance frequency is about 14.0 MHz and the communication distance is 231 to 270 mm.

FIG. 6 shows the characteristics of different types of recording media with the number of turns = 5 and the pitch = 0.35 mm. FIG. 6 shows the following.
・ Because it is a different type of recording medium, the variation in resonance frequency and communication distance for each recording medium has increased. In particular, the variation in communication distance is very large.
The resonance frequency is 15.00-15.70 MHz, and the communication distance is 222-310 mm.

FIG. 7 shows the characteristics of different types of recording media with the number of turns = 5 and the pitch = 1.35 mm. FIG. 7 shows the following.
・ Because it is a different type of recording medium, the variation in resonance frequency and communication distance for each recording medium has increased. In particular, the variation in communication distance is very large.
The resonance frequency is 14.10 to 14.40 MHz, and the communication distance is 213 to 309 mm.

FIG. 8 shows the characteristics of different types of recording media with the number of turns = 4 and the pitch = 0.45 mm. FIG. 8 shows the following.
・ Because it is a different type of recording medium, the variation in resonance frequency and communication distance for each recording medium has increased.
The resonance frequency is 14.0 to 14.50 MHz, and the communication distance is 241 to 280 mm.

  Comparing FIG. 5 and FIG. 8, it can be seen that in FIG. 8, the variation in the communication distance is smaller and the communication distance is longer. 6 and 7, it can be seen that when the number of turns is increased from 4 or the pitch is increased to 1.35 mm, the variation in the communication distance becomes very large. In order to satisfy the condition (3) described above, it is desirable not to increase the number of turns or increase the pitch too much.

  From the viewpoint of use in the library lending management system, the number of turns of the conductor of the antenna 101 and the interval are affixed to a plurality of types of recording media so as to satisfy the above conditions (1) and (3), that is, while ensuring a predetermined communication distance. It is preferable that the antenna is set so that the variation in the communication distance of the antenna is reduced. When the above data are combined, it can be said that the example of FIG. 8 is most suitable for the above-mentioned conditions (1) and (3).

  It has been found that the resonance frequency is lowered when the antenna 101 is attached to a recording medium. This is presumed to be caused by capacitive coupling between the antenna and the recording surface of the recording medium. Therefore, it is preferable to set the resonance frequency of the antenna 101 in a state before being attached to the recording medium to be higher than the use frequency of the IC chip 102 (eg, 13.56 MHz). In this way, optimal performance can be exhibited in the usage state of the IC tag. FIG. 9 shows the characteristics of the antenna before being attached to the recording medium (CD). FIG. 9 shows an antenna under the same conditions as in FIG. The resonance frequency of the antenna before pasting is 19.2 MHz by a dip meter, but when pasted on a recording medium, it is lowered by about 25% to 14.00-14.50 MHz as shown in FIG.

  The embodiment of the present invention is characterized in that the antenna is configured by using a conductive wire rather than printing or etching. This is based on the inventor's knowledge that almost no communication is possible in the state of being attached to a recording medium by printing or etching, but communication is possible if it is a conductor. The cost of conducting wire antennas is higher than that of printing and etching, but in the case of a library rental management system, IC tags are attached to recording media afterwards, so they are not used in large quantities, so the cost is a problem. do not become.

  As described above, according to the embodiment of the present invention, since the antenna is formed of a conducting wire having a substantially circular cross section, and the antenna is disposed along the circumference of the recording medium, the outer diameter of the coiled antenna can be increased. Because the output can be increased, the communication distance has been extended to a practical level. Appropriate selection of the number of turns and spacing of the conductors that make up the antenna allows it to be used by being affixed to various recording media. In addition, as a result of the increased output, the antenna can be arranged on the recording area of the recording medium in a state of being attached to the recording medium, so that the reliability can be increased. In the conventional method which cannot be arranged on the recording area, the antenna must be provided on the outer peripheral portion, and the finger and the member of the driving device come into contact with each other to damage the antenna and the IC chip, which is not practical.

  By the way, the above-mentioned condition (2) Even when books and recording media are stacked and placed in a reader / writer, it is necessary to be able to communicate with the IC tags of all books and recording media. It can be satisfied by comprising like this. In order to more reliably communicate with the IC tag, it is preferable to prevent interference between the IC tags. One way to do this is to increase the size of the antenna as described above and prepare antennas of various shapes so that adjacent antennas do not overlap when recording media are stacked. . If only one type of antenna in FIG. 1 is used, when the recording media are stacked, the antennas are very close to each other, and the one closer to the reader / writer can communicate, but the farther away is the closer antenna. Communication may be difficult due to interference.

  Even when the antenna has various shapes, it is preferable to arrange at least a part of the antenna along the circumference of the recording medium in order to enlarge the area of the antenna as much as possible. As the shape of the antenna, a circular shape shown in FIG. 1 or a non-circular shape can be adopted. The term “non-circular” as used herein means that at least a part of the non-circular shape is arranged along the circumference of the recording medium to form an arc, but a part of the non-circular shape is arranged away from the circumference and inside. 11 (a) is also a non-circular type referred to here. In order to keep the balance of rotation, it is desirable that the arcs arranged along the circumference with respect to the rotation center of the recording medium are symmetrical with each other, and the parts arranged inside the circumference are also symmetrical with each other. .

  The antenna 101 in FIG. 10 includes two arcs (circumferential portions) 101a having a quarter of the circumference and two portions (non-circular portions) having a shape in which a quarter of the circumference is bent inward. ) 101b. The circumferential portions 101a are arranged symmetrically with respect to the rotation center of the recording medium. The same applies to the non-circumferential portion 101b. The antenna 101 in FIG. 10 has a shape like a so-called weight.

  The antenna 101 shown in FIG. 11A is composed of two circular arcs (circumferential portion) 101a that is about 1/6 of the circumference, and a linear portion (non-circular portion) 101b that connects the ends. The circumferential portion 101a and the non-circular portion 101b are arranged symmetrically as in FIG. The antenna of FIG. 10 has a shape close to a rectangle. In the case of FIG. 11, the sheet 10 does not have to be a disk shape, and may have a shape similar to that of the antenna 101 as indicated by a dotted line in FIG. 11, for example. The sheet 10 has a shape suitable for the recording medium, and includes a shape similar to the antenna of FIG.

  In the above description, the example in which at least a part of the antenna is arranged along the circumference of the recording medium and has an arc has been described. However, this is a case where the antenna does not have a portion along the circumference. However, the same action and effect are produced. If at least a part of the antenna is arranged along the circumference of the recording medium, the area of the recording medium can be used most effectively. However, if the area of the antenna can be increased, the arrangement along the circumference is not essential. . FIG. 11B shows an example of such an antenna. This figure shows the case where the antenna is square.

  By adopting various antenna shapes as shown in FIGS. 1, 10, and 11, the antennas of the recording media interfere with each other even when a plurality of recording media with IC tags attached are stacked. Can be prevented. From the viewpoint of preventing interference, the shape of the antenna is preferably different for each recording medium. In the case of the circular antenna of FIG. 1, there is a possibility of interference of the antenna even if the recording medium is rotated, but even if the shape is the same as that shown in FIGS. Antenna interference can be prevented. That is, even when only one type of non-circular antenna is used, since the recording medium faces in various directions at the time of use, the antennas hardly overlap completely, and the possibility of interference is reduced.

  In addition, although the said description has demonstrated taking the use of the rental management system of a library as an example, this invention is not limited to the said use. For example, the present invention can be applied to any application that needs to satisfy some or all of the above conditions (1) to (3).

  The present invention is not limited to the above embodiments, and various modifications can be made within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say.

FIG. 1 is a view showing an IC tag attaching sheet for a recording medium according to an embodiment of the present invention. Fig.1 (a) is a top view, FIG.1 (b) is arrow sectional drawing of the AA line of a top view.
[FIG. 2] FIG. 2 (a) is a detailed sectional view of an antenna portion according to an embodiment of the present invention, FIG. 2 (b) is a detailed sectional view of the IC chip portion, and FIG. 2 (c) is a printed antenna portion. Alternatively, a detailed cross-sectional view when formed by etching, FIG. 2D is an example of a plan view of an IC chip.
FIG. 3 is a diagram showing a state where an IC tag attaching sheet for recording medium according to an embodiment of the present invention is attached to a recording medium. Fig.1 (a) is a top view, FIG.1 (b) is arrow sectional drawing of the AA line of a top view.
[FIG. 4] Measured data of the resonance frequency and communication distance of the antenna according to the embodiment of the present invention (same type CD, number of windings = 4, interval = 0.35 mm).
[FIG. 5] Measured data of the resonance frequency and communication distance of the antenna according to the embodiment of the present invention (heterogeneous CD, number of windings = 4, interval = 0.35 mm).
[FIG. 6] Measured data of the resonance frequency and communication distance of the antenna according to the embodiment of the present invention (different CD, number of windings = 5, interval = 0.35 mm).
[FIG. 7] Actual measurement data of the resonance frequency and communication distance of the antenna according to the embodiment of the present invention (different CD, number of windings = 5, interval = 1.35 mm).
[FIG. 8] Measured data of the resonance frequency and communication distance of the antenna according to the embodiment of the present invention (heterogeneous CD, number of windings = 4, interval = 0.45 mm).
[FIG. 9] The characteristic before sticking to the recording medium of the antenna which concerns on embodiment of this invention is shown.
FIG. 10 is a plan view showing a non-circular antenna shape according to the embodiment of the present invention.
FIG. 11 is a plan view showing another non-circular antenna shape according to the embodiment of the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 IC tag sticking sheet for recording media 2 Recording medium 2a Outer edge of recording medium 2b Edge of inner hole of recording medium 10 Sheet (base)
10a Outer edge of sheet 10b Edge of inner hole of sheet 11 Double-sided tape 12 Separator 21 Recording surface of recording medium (aluminum thin film)
101 Antenna 101a Circumferential portion 101b of antenna Non-circular portion of antenna 102 IC chip 102a IC chip body 102b IC chip mounting portion 103 Connection lead 104 Counterweight

Claims (2)

A disc-like thin plate-like base portion having the same shape as that of a disc-like optical recording medium such as a CD or DVD containing a recording area for recording information therein, and a loop-shaped antenna provided in the base portion; An IC chip that performs non-contact communication through the antenna,
In a state where the sheet is attached to the optical recording medium,
The antenna is provided on the base so as to be positioned on a recording area of the optical recording medium;
The resonance frequency of the antenna in a state before being attached to the optical recording medium is set higher than the use frequency of the IC chip,
The antenna includes a plurality of arc-shaped circumferential portions located on the circumference of the optical recording medium, and a plurality of non-circular portions located on the inner side of the optical recording medium. The circumferential portions are arranged symmetrically with respect to the rotation center of the recording medium, and the non-circular portions are arranged symmetrically,
Each of the plurality of circumferential portions is a portion corresponding to ¼ of the circumference, and each of the plurality of non-circumferential portions is a portion corresponding to ¼ of the circumference, respectively. It is the part of the shape bent to
Alternatively, each of the plurality of circumferential portions is a portion corresponding to 1/6 of the circumference, and each of the plurality of non-circumferential portions ties two opposite ends of the plurality of circumferential portions, respectively. An IC tag affixing sheet for optical recording media, characterized in that there are two linear portions .   2. The IC tag affixing sheet for optical recording media according to claim 1, wherein the antenna is formed by winding a conducting wire a plurality of times, and the plurality of conducting wires are arranged at regular intervals.

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