Source: http://www.google.com/patents/US7405664?dq=6,232,546
Timestamp: 2017-11-22 11:16:42
Document Index: 251150291

Matched Legal Cases: ['arts 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'art 9', 'art 9', 'arts 15', 'arts 15', 'arts 14', 'arts 14', 'arts 15', 'arts 14', 'art 14', 'art 14', 'arts 14', 'art 14', 'art 14', 'arts 15', 'art 15', 'art 15', 'arts 15', 'art 15', 'art 15', 'arts 14', 'art 14', 'art 14', 'arts 14', 'arts 14', 'arts 14', 'arts 14', 'art 14', 'art 14']

Patent US7405664 - Radio frequency IC tag and method for manufacturing the same - Google Patents
A radio frequency IC tag and a manufacturing method for the same includes an IC chip on which information is stored, and an antenna for transmitting the information that is stored on the IC chip. In the antenna, a power-feeding part on which the IC chip is mounted extends along a direction in which an...http://www.google.com/patents/US7405664?utm_source=gb-gplus-sharePatent US7405664 - Radio frequency IC tag and method for manufacturing the same
Publication number US7405664 B2
Application number US 11/052,804
Also published as DE602005020391D1, EP1605397A2, EP1605397A3, EP1605397B1, US20050275539
Publication number 052804, 11052804, US 7405664 B2, US 7405664B2, US-B2-7405664, US7405664 B2, US7405664B2
Patent Citations (8), Referenced by (171), Classifications (30), Legal Events (5)
US 7405664 B2
an antenna serving to radiate by electromagnetic transmission the information that is stored on the IC chip;
in said antenna, a power-feeding part equipped with the IC chip has a longitudinal axis along a direction in which an electric current flows, and radiation parts are formed so that a width of said radiation parts becomes wider than that of the power-feeding part with respect to the longitudinal axis of the power-feeding part, said radiation parts extending from the power-feeding part at both sides thereof along the direction in which the electric current flows, the power feeding part being provided with an L-shaped slit for attaining an impedance matching between said IC chip and said antenna, and each of terminals of said IC chip being connected to each end of said power feeding part across said L-shaped slit.
3. A radio frequency IC tag according to claim 2, wherein the power-feeding part and the radiation parts are electrically connected each other.
4. A radio frequency IC tag according to claim 2, wherein the power-feeding part and the radiation parts are continuously connected each other with a conductor.
5. A radio frequency IC tag according to claim 2, wherein: an insulation material is provided between the power-feeding part and the radiation parts, and the power-feeding part and the radiation parts are coupled each other by means of electrostatic capacitive coupling.
6. A radio frequency IC tag according to claim 1, wherein:
7. A radio frequency IC tag according to claim 1, wherein said power-feeding part is provided at a position where the radiation parts are symmetric in the up and down direction and also in the right and left direction.
8. A radio frequency IC tag according to claim 1, wherein said power-feeding part is provided at a position where the radiation parts become asymmetric at least either in the up-and-down direction or in the right-and-left direction.
9. A radio frequency IC tag according to claim 8, wherein at least one radiation part is provided with openings different in shape at arbitrary positions thereof.
10. A radio frequency IC tag according to claim 9, wherein the openings are a circle or a polygon in shape.
11. A radio frequency IC tag according to claim 10, wherein the power-feeding part is positioned in association with a position of one or more openings with which at least one of the radiation parts is provided.
12. A radio frequency IC tag according to claim 8, wherein:
13. A radio frequency IC tag according to claim 12, wherein the opening has the same shape as that of the notch.
14. A radio frequency IC tag according to claim 12, wherein the opening has a shape different from that of the notch.
15. A radio frequency IC tag according to claim 7, wherein at least one radiation part is provided with at least one opening at an arbitrary position thereof.
16. A radio frequency IC tag according to claim 7, wherein at least one radiation part is provided with notches different in shape at arbitrary positions on the outer periphery thereof.
17. A radio frequency IC tag according to claim 7, wherein at least one radiation part is provided with at least one notch at an arbitrary position on the outer periphery thereof.
18. A radio frequency IC tag according to claim 17, wherein the at least one notch is a circle or a polygon in shape.
19. A radio frequency IC tag according to claim 17, wherein the power-feeding part is positioned in association with the position of the at least one notch with which the radiation part is provided on the outer circumference thereof.
20. A radio frequency IC tag according to claim 1, wherein the power-feeding part and the radiation parts are electrically connected each other.
21. A radio frequency IC tag according to claim 1, wherein the power-feeding part and the radiation parts are continuously connected each other with a conductor.
22. A radio frequency IC tag according to claim 1, wherein:
23. A radio frequency IC tag comprising:
in said antenna, a power-feeding part equipped with the IC chip has a longitudinal axis along a direction in which an electric current flows, and radiation parts are formed so that a width of said radiation parts becomes wider than that of the power-feeding part with respect to the longitudinal axis of the power-feeding part, said radiation parts extending from the power-feeding part at both sides thereof along the direction in which the electric current flows
wherein an insulation material is provided between the power-feeding part and the radiation parts, and the power-feeding part and the radiation parts are coupled each other by means of electrostatic capacitive coupling.
24. A radio frequency IC tag comprising:
an antenna serving to radiate by electromagnetic transmission the information that is stored on the IC chip,
in said antenna, a power-feeding part equipped with the IC chip has a longitudinal axis along a direction in which an electric current flows, and radiation parts are formed so that a width of said radiation parts becomes wider than that of the power-feeding part with respect to the longitudinal axis of the power-feeding part, said radiation parts extending from the power-feeding part at both sides thereof along the direction in which the electric current flows, the power feeding part being provided with an L-shaped slit for attaining an impedance matching between said IC chip and said antenna, and each of terminals of said IC chip being connected to each end of said power feeding part across said L-shaped slit, and
25. A radio frequency IC tag according to claim 24, wherein said antenna has an H shape defined by the power-feeding part and the radiation parts.
FIG. 1 is a plan view illustrating an H type antenna used in a radio frequency IC tag according to a first embodiment of the present invention. As shown in FIG. 1, an H type antenna 1 used in the radio frequency IC tag has a so-called H shape in which the antenna width D1 is narrowed in the central part of the antenna forming a constriction 1 a extending in a direction of a length L1 while the antenna width D is widened at both side parts (peripheral radiation parts) 14 of the antenna 1 extending in the direction of the length L. In addition, an IC chip 2 is mounted on the central part of the H type antenna 1. The H type antenna 1 functions as a strip antenna. The H type antenna 1 takes preventive measures against electrostatic discharge damage, and performs impedance matching. Therefore, a consecutive key-shaped (or L-shaped) slit 5 is formed in the central part equipped with the IC chip 2 in such a manner that the IC chip 2 is placed across the slit 5, and the terminals of the IC chip 2 are electrically connected on each side of the slit 5. Accordingly, the above-mentioned constriction 1 a at central part becomes a power-feeding part for feeding antenna current; and both side parts (peripheral parts) 14 become radiation parts for emitting an antenna radio wave. The central constriction 1 a is generally rectangular in this embodiment, and the radiation parts 14 are also rectangular but of greater width than the constriction 1 a, thereby forming an antenna that resembles an “H”.
Thus, widening the antenna width D in both side parts of the H type antenna 1 extending in the direction of the length L (longitudinal direction) makes it possible to obtain the maximum current in the central part (that is, constriction 1 a) of the H type antenna 1 to which the IC chip 2 is connected. As a result, the electromagnetic energy is concentrated on the peripheral radiation parts 14 of the antenna which surround the IC chip 2. Accordingly, if the antenna width D of the H type antenna 1 is set at a specified value, even if the length L is shortened the antenna efficiency increases, leading to an improvement in communication distance. To be more specific, in the case of the conventional microstrip antenna that is formed of a ground electrode and a patch electrode, even if the patch electrode is configured to have an H shape, an IC chip cannot be mounted on the patch electrode. Therefore, the magnetic field is concentrated after all, resulting in an increase in inductance. Accordingly, although an effect of decreasing the resonance frequency is produced, an improvement in communication distance is not attained. In contrast, since the H type antenna 1 of this embodiment functions as a strip antenna that does not need a ground electrode, the IC chip 2 can be mounted on the central part constriction 1 a of the antenna, where the electromagnetic energy is most concentrated, creating a power-feeding part. As a result, the antenna efficiency is improved, which makes it possible to improve the communication distance.
As shown in FIG. 2, on the condition that the antenna length L is a constant (20 mm), the antenna width D is changed. In this case, when the antenna width D is 40 mm or less, it is possible to carry out communications. When the antenna width D is 24 mm, the communication distance S is 119 mm, which is the maximum communication distance. More specifically, as shown in FIG. 1, the IC chip 2 is mounted on the constriction 1 a in the central part of the H type antenna 1. When an antenna current flows along the direction of the length L from the constriction of the H type antenna 1 toward widened peripheral radiation parts 14 at both sides, the maximum current is measured at the constriction while the electric current spreads over the widened peripheral parts 14 at both sides. At this time, the electromagnetic energy of the widened peripheral parts 14 at both sides is concentrated on the constriction 1 a (that is, the part equipped with the IC chip 2) in the central part of the H type antenna 1. Accordingly, the antenna efficiency is improved.
What will be described here is a manufacturing method for manufacturing a radio frequency IC tag 10, the manufacturing method including a first process, a second process, and a third process. More specifically, the first process is a process in which when a metallic conductor is used to form an antenna on a surface of an insulative substrate, the central part constriction 1 a is patterned into a rectangular shape, and peripheral radiation parts 14 extending at both sides along the longitudinal direction of the central part are patterned so that the width of the peripheral parts 14 becomes wider than the width of the central part constriction 1 a with respect to the longitudinal direction of the central part constriction 1 a. The second process is a process in which an IC chip 2 is mounted on the central part constriction 1 a, and each terminal of the IC chip 2 is connected to the metallic conductor across a slit 5 formed in the central part constriction 1 a. The third process is a process of coating, with an isolation (insulation) cover 4, the metallic conductor forming the central part constriction 1 a and the peripheral radiation parts 14, and the IC chip 2.
Incidentally, in the first process, the peripheral parts 14 may also be symmetrically patterned with respect to the axis of the central part constriction 1 a in the longitudinal direction.
As shown in FIG. 3B, a metallic conductor such as copper, silver, etc., is patterned into an H shape on a surface of an antenna base material 12. For example, metallic paste, such as copper, is printed patterning to form an H-shaped pattern and printed out; or a metallic pattern layer is plated to form an H-shaped pattern; or a thin metal film is etched to form an H-shaped pattern. In this case, as shown in FIG. 3A, the H type antenna 1 is provided with a consecutive key-shaped slit 5 at the constriction 1 a in the central part thereof. It is to be noted that as described above, this slit 5 is provided in order to take preventive measures against electrostatic discharge damage to the IC chip 2, and to perform impedance matching. Moreover, the IC chip 2 is placed across the slit 5 in the longitudinal direction of the H type antenna 1, and electrodes of the IC chip 2 are connected to metal parts on both sides of the slit 5 (the IC chip 2 is connected across the slit 5). FIG. 3B is a cross section of FIG. 3A, taken along line A-A.
Next, a manufacturing process of manufacturing an H type antenna 11 according to another embodiment will be described. FIGS. 4A through 4C are diagrams, each illustrating as an example a manufacturing process of manufacturing an H type antenna according to another embodiment. Here, peripheral parts 14 extending at both sides of the central part element 6 (forming a constriction 1 a) are formed as auxiliary antennas 8 a, 8 b. The auxiliary antennas 8 a, 8 b are connected to the central part element 6 by electrostatic capacitive coupling.
The manufacturing process includes: a first process in which an antenna 6 a is patterned with a metallic conductor on the surface of the antenna base material 6 b; a second process in which the IC chip 2 is placed in the central part constriction 1 a of the antenna 6 a, and each terminal of the IC chip 2 is connected to the antenna 6 a (each terminal is connected to the antenna across a slit 5); a third process in which an insulation film 7 is coated on the surface of the antenna 6 a; a fourth process in which over a wide area including the insulation film 7 on the antenna 6 a, the first auxiliary antenna 8 a and the second auxiliary antenna 8 b are formed across the IC chip 2; and a fifth process in which the whole surface including the first auxiliary antenna 8 a, the second auxiliary antenna 8 b, and the IC chip 2 are coated with an isolation cover 4.
As shown in FIG. 4B, on a surface of the antenna base material 6 b, a metallic conductor such as copper, silver, etc. is used to pattern the antenna 6 a having a rectangular shape in the longitudinal direction. The patterning of the antenna 6 a is achieved by performing pattern printing of metallic paste such as copper to print out the pattern, or by plating a metallic pattern layer, or by etching a thin metal film. In this case, as shown in FIG. 4A, the antenna 6 a is provided with a consecutive key-shaped slit 5 at the constriction 1 a in the central part thereof. Moreover, the IC chip 2 is placed across the slit 5 in the longitudinal direction of the antenna 6 a, and each electrode of the IC chip 2 is connected to the antenna 6 a (the IC chip 2 is connected to the antenna across the slit 5). Incidentally, FIG. 4B is a B-B cross section of FIG. 4A.
Further, as shown in FIG. 4B, the insulation film 7 is coated on the surface of the antenna 6 a. This makes it possible to form an element 6 into which the antenna base material 6 b including the insulation film 7, the antenna 6 a, and the IC chip 2 are integrated.
Next, the adhesive sheet 3 is placed on the antenna base material 6 b side of the element 6, and then the first auxiliary antenna 8 a and the second auxiliary antenna 8 b are formed with the IC chip 2 sandwiched therebetween over a wide area including the insulation film 7 on the antenna 6 a by pattern printing, plating, etching, or the like. Thus, an H type antenna as shown in FIG. 4A is formed.
After forming such an H type antenna, as shown in FIG. 4B, an insulative cover seal 4 is coated on the whole surface of the adhesive sheet 3 including the element 6, the first auxiliary antenna 8 a, and the second auxiliary antenna 8 b. As a result, a radio frequency IC tag 11 as shown in FIG. 4C is formed. To be more specific, as is the case with FIG. 3, what is formed is a thin, square, and small-size radio frequency IC tag 11 having a length of 22 mm in the longitudinal direction, a width of 22 mm in the lateral direction, and a thickness of about 1 mm.
It is to be noted that the antenna base material 6 b is used here to reinforce the antenna 6 a, and accordingly it is also possible to omit the antenna base material 6 b if necessary, and to form the antenna 6 a directly on the adhesive sheet 3.
In the fourth process illustrated in FIG. 4B, because the first auxiliary antenna 8 a and the second auxiliary antenna 8 b are formed on the surface of the antenna 6 a of the element 6 through the insulation film 7, the antenna 6 a, the first auxiliary antenna 8 a, and the second auxiliary antenna 8 b are coupled not by ohmic contact but by electrostatic capacitive coupling. Because a high-frequency current flows through the H type antenna formed in this manner, electrical connection between the antenna 6 a and the first auxiliary antenna 8 a and the second auxiliary antenna 8 b is sufficiently made although the connection is electrostatic capacitive coupling. Thus, central part constriction 1 a acts as a power-feeding part, and auxiliary antennas 8 a, 8 b act as radiation parts.
In the case of the ohmic contact, it is necessary to use anisotropic conductive adhesive for the connection between the antenna and the IC chip so as to cause an electric current to flow. In contrast, in this embodiment, because the antenna 6 a, the first auxiliary antenna 8 a, and the second auxiliary antenna 8 b are coupled by the electrostatic capacitive coupling, it is possible to form a capacitor used for the electrostatic capacitive coupling by making use of the insulation film 7 as a dielectric (insulation material) as described above. Thus, a material used in other processes, such as a resist material, a sticky material, and an adhesive material, is made use of as a dielectric between the antenna 6 a and the first auxiliary antenna 8 a and the second auxiliary antenna 8 b, and thereby it is possible to form a capacitor.
Incidentally, in FIG. 4A, the first auxiliary antenna 8 a is provided with a gap 13 for the antenna 6 a formed with slit 5. However, the second auxiliary antenna 8 b may also be provided with gap 13, or both the first auxiliary antenna 8 a and the second auxiliary antenna 8 b may also be provided with gap 13. If both of the first auxiliary antenna 8 a and the second auxiliary antenna 8 b are provided with gap 13, it is not necessary to take a direction of the antenna 6 a into consideration when the radio frequency IC tag is manufactured.
FIG. 5 is a plan view illustrating an O type (dumbbell or oval type) antenna used in a radio frequency IC tag according to a second embodiment of the present invention. As shown in FIG. 5, an O type antenna 9 having a generally circular or oval shape has a configuration in which the central part 9 a between two pieces of semicircular metal foil 15 having a radius of R is connected with rectangular metal foil having a width of D2. The rectangular metal foil part is equipped with the IC chip 2 to form a radio frequency IC tag. When an antenna current flows from the IC chip 2 of the O type antenna 9 having such a shape toward a direction indicated by an arrow in FIG. 5, the maximum current flows in the central part 9 a (the part equipped with the IC chip 2 which forms a power-feeding part), and the antenna current then flows toward semicircular parts 15 at both sides, which act as radiation parts. As a result, the electromagnetic energy of the semicircular parts 15 at both sides surrounds the IC chip 2, and is thereby concentrated around the IC chip 2. Therefore, even if an O type antenna having small radius R is used, the antenna efficiency increases, leading to an improvement in communication distance. Using a radio frequency IC tag having the O type antenna 9 makes it possible to improve the communication distance even if the radio frequency IC tag is mounted on, for example, a cap of a bolt.
FIGS. 6A through 6D are diagrams illustrating variations of asymmetric shapes of H type antennas according to the third embodiment of the present invention. In contrast to a symmetric radio frequency IC tag, as shown in FIG. 6A, which is a basic type of the H type antenna 1, a constriction 1 a of which stays in the central part, variation 1 shown in FIG. 6B is for a power-feeding-point top-and-bottom offset type radio frequency IC tag in which the constriction 1 a of the H type antenna 1 is shifted downward (or upward), and in which a slit 5 is formed in the constriction 1 a and an IC chip 2 is placed across the slit 5.
In addition, variation 2 shown in FIG. 6C is for a power-feeding-point right-and-left-offset type radio frequency IC tag in which the radiation parts 14 of the right and left antennas of the H type antenna 1 are made asymmetric with the constriction 1 a of the H type antenna 1 not being shifted from the central part in the up or down direction. Moreover, variation 3 shown in FIG. 6D is a power-feeding-point up-and-down right-and-left-offset type radio frequency IC tag in which the radiation parts 14 of the right and left antennas of the H type antenna 1 are made asymmetric with the constriction 1 a of the H type antenna 1 being shifted downward (or upward). If the H type antenna having the asymmetric shape as shown in FIGS. 6B, 6C, 6D is used, although the antenna efficiency slightly decreases as compared with the H type antenna having the symmetric shape shown in FIG. 6A, changing an antenna shape in a range within which the required communication distance is ensured makes it possible to satisfy the convenience of attaching the IC tag case to an object to which the case is to be attached.
FIGS. 7A through 7D are diagrams illustrating variations of asymmetric shapes of O type antennas according to the third embodiment of the present invention. In contrast to a symmetric radio frequency IC tag, as shown in FIG. 7A, which is a basic type of the O type antenna 9, a constriction 9 a of which is located in the central part, variation 1 shown in FIG. 7B is a power-feeding-point top-and-bottom offset type radio frequency IC tag in which the constriction 9 a of the O type antenna 9 is shifted downward (or upward), and in which a slit 5 is formed in the constriction 9 a and an IC chip 2 is placed across the slit 5.
In addition, variation 2 shown in FIG. 7C is a power-feeding-point right-and-left-offset type radio frequency IC tag in which the radiation areas of the right and left antennas of the O type antenna 9 are made asymmetric with the constriction 9 a of the O type antenna 9 not being shifted from the central part. Moreover, variation 3 shown in FIG. 7D is a power-feeding-point up-and-down right-and-left-offset type radio frequency IC tag in which the radiation areas 15 of the right and left antennas of the O type antenna 9 are made asymmetric with the constriction 9 a of the O type antenna 9 being shifted downward (or upward). If the O type antenna having the asymmetric shape as shown in FIGS. 7B, 7C, 7D is used, although the antenna efficiency slightly decreases as compared with the O type antenna having the symmetric shape shown in FIG. 7A, changing an antenna shape in a range within which the required communication distance is ensured makes it possible to satisfy the convenience of attaching the IC tag case to an object to which the case is to be attached.
FIG. 8 is an outline drawing illustrating one embodiment of an O type antenna having an asymmetric shape, which is applied to the third embodiment of the present invention. As shown in FIG. 8, the outside diameter of the O type antenna 9 is 24 mm; and the central part of the O type antenna 9 is provided with an empty part or opening 22 having a diameter of 6 mm, into which a leg of the IC tag case (not shown) may be inserted. Therefore, the constriction 9 a having a width of 1.5 mm and a length of 2.0 mm is provided at a position that is shifted from the center of the O type antenna 9 by 6 mm. The constriction 9 a connects between the right-half and left-half of the antenna radiation parts 15. In addition, a key-shaped slit 5 having a width of 0.15 mm is formed in proximity to the center of the constriction 9 a. Incidentally, is has been confirmed by an experiment that the O type antenna having the shape as shown in FIG. 8 is capable of achieving the communication distance of 100 mm.
FIGS. 9A through 9D are diagrams illustrating variations of openings of H type antennas according to the third embodiment of the present invention. In contrast to a symmetric radio frequency IC tag, as shown in FIG. 9A, which is a basic type of the H type antenna 1, a constriction 1 a of which stays in the central part, variation 1 shown in FIG. 9B is a power-feeding-point top-and-bottom offset type radio frequency IC tag in which the constriction 1 a of the H type antenna 1 is shifted downward (or upward), and in which a slit 5 is formed in the constriction 1 a, an IC chip 2 is placed across the slit 5, and an opening 22 is formed in proximity to the central part of the H type antenna 1.
In addition, variation 2 shown in FIG. 9C is a power-feeding-point right-and-left-offset type radio frequency IC tag in which the radiation parts 14 of the right and left antennas of the H type antenna 1 are made asymmetric with the constriction 1 a of the H type antenna 1 not being shifted from the central part, and in which the opening 22 is formed in one antenna radiation part 14 (the left antenna radiation part in the FIG. 9C), the radiation area of which is wider than that of the other antenna radiation part 14 of the H type antenna 1. Moreover, variation 3 shown in FIG. 9D is a power-feeding-point top-and-bottom right-and-left-offset type radio frequency IC tag in which a constriction 1 a of the H type antenna 1 is shifted downward (or upward) and the radiation area of the right and left antenna radiation parts 14 of the H type antenna 1 are made asymmetric, and in which the opening 22 is formed in one antenna radiation part 14 (the left antenna radiation part in the FIG. 9D), the radiation area of which is wider than that of the other antenna radiation part 14 of the H type antenna 1.
To be more specific, also in the case where the opening 22 exists in the H type antenna 1, a position at which the IC chip 2 is mounted follows the mounted position shown in the variations of asymmetric shapes of H type antennas in FIG. 6. Incidentally, the shape of the opening 22 is not limited to the circle as show in FIG. 9; the shape may also be any type of arbitrary polygon or other desired shape. In addition, it is desirable that depending on a position of the opening 22, the power-feeding point (that is, a position of the constriction 1 a) be properly moved. Moreover, the position of the opening 22 can be arbitrarily changed. Further, two or more openings 22 having the same shape, or each having a shape different from one another, may also be formed in the antenna.
FIGS. 10A through 10D are diagrams illustrating variations of openings of O type antennas according to the third embodiment of the present invention. In contrast to a symmetric radio frequency IC tag, as shown in FIG. 10A, which is a basic type of the O type antenna 1, a constriction 9 a of which stays in the central part, variation 1 shown in FIG. 10B is a power-feeding-point top-and-bottom-offset type radio frequency IC tag in which the constriction 9 a of the O type antenna 9 is shifted downward (or upward), and in which a slit 5 is formed in the constriction 9 a, an IC chip 2 is placed across the slit 5, and an opening 22 is formed in proximity to the central part of the O type antenna 9.
In addition, variation 2 shown in FIG. 10C is a power-feeding-point right-and-left-offset type radio frequency IC tag in which the radiation areas of the right and left antenna radiation parts 15 of the O type antenna 9 are made asymmetric with the constriction 9 a of the O type antenna 9 not being shifted from the central part, and in which the opening 22 is formed in one antenna radiation part 15 (the left antenna radiation part in the FIG. 10C), the radiation area of which is wider than that of the other antenna radiation part 15 of the O type antenna 9. Moreover, variation 3 shown in FIG. 10D is a power-feeding-point top-and-bottom right-and-left-offset type radio frequency IC tag in which a constriction 9 a of the O type antenna 9 is shifted downward (or upward) and the radiation areas of the right and left antenna radiation parts 15 of the O type antenna 9 are made asymmetric, and in which the opening 22 is formed in one antenna radiation part 15 (the left antenna radiation part in the FIG. 10D), the radiation area of which is wider than that of the other antenna radiation part 15 of the O type antenna 9.
To be more specific, also in the case where the opening 22 exists in the O type antenna 9, a position at which the IC chip 2 is mounted follows the mounted position shown in the variations of asymmetric shapes of O type antennas in FIGS. 7A through 7D. Incidentally, the shape of the opening 22 is not limited to the circle as shown in FIGS. 10B-10D; the shape may also be an arbitrary polygon or other shape. In addition, it is desirable that depending on a position of the opening 22, the power-feeding point (that is, a position of the constriction 9 a) be properly moved. Moreover, the position of the opening 22 can be arbitrarily changed. Further, two or more openings 22 having the same shape, or each having a shape different from one another, may also be formed in the antenna.
FIGS. 11A through 11D are diagrams illustrating variations of outer circumferential notches of H type antennas according to the third embodiment of the present invention. As shown in FIG. 11A, in the basic H type antenna 1, the constriction 1 a of which exists in the center to form a symmetric shape, it is also possible to provide a notch having an arbitrary shape on the outer circumference of each of the right and left antenna radiation parts 14. For example, in the H type antenna 1 shown in FIG. 11A, a semicircular notch 23 a is formed in the upper part on the outer periphery of the antenna radiation part 14 on the left side, and in addition, a rectangular notch 23 c is formed in the lower part on the outer periphery of the antenna radiation part 14 on the right side. In addition, variation 1 shown in FIG. 11B is for a power-feeding-point top-and-bottom-offset type radio frequency IC tag in which the constriction 1 a of the H type antenna 1 is shifted downward, a slit 5 is formed in the constriction 1 a, the IC chip 2 is placed across the slit 5, and semicircular notches 23 b, 23 a are further formed in proximity to the central part on the outer periphery of the right and left antennas radiation parts 14 of the H type antenna 1, respectively.
Moreover, variation 2 shown in FIG. 11C is a power-feeding-point right-and-left-offset type radio frequency IC tag in which the areas of the right and left antenna radiation parts 14 of the H type antenna 1 are made asymmetric with the constriction 1 a of the H type antenna 1 not being shifted from the central part in the up-and-down direction, and semicircular notches 23 b, 23 a are further formed in proximity to the lower parts on the outer periphery of the right and left antenna radiation parts 14 of the H type antenna 1 respectively. Further, variation 3 shown in FIG. 11D is for a power-feeding-point top-and-bottom right-and-left-offset type radio frequency IC tag in which the radiation areas of the right and left antennas of the H type antenna 1 are made asymmetric with the constriction 1 a of the H type antenna 1 being shifted downward, and semicircular notches 23 b, 23 a are further formed in proximity to the central parts on the outer periphery of the right and left antenna radiation parts 14 of the H type antenna 1 respectively.
To be more specific, also in the case where the notches exist on the outer periphery of the H type antenna 1, a position at which the IC chip 2 is mounted follows the variations of asymmetric shapes of H type antennas in FIGS. 6A through 6D, respectively. Incidentally, the shape of the notch is not limited to a circle, and accordingly the shape may also be any arbitrary polygon. In addition, it is desirable that depending on positions of the notches, the power-feeding point (that is, a position of the constriction 1 a) be properly moved. Moreover, the positions of the notches can be arbitrarily changed. Moreover, a plurality of notches may exist, and a notch and an opening may coexist. Moreover, a shape of the notch in the right antenna radiation part 14 of the H type antenna 1 may differ from that of the notch in the left antenna radiation part 14; and shapes of a plurality of notches in the right antenna radiation part may differ from those of a plurality of notches in the left antenna radiation part. It is to be noted that positions of notches in the right and left antenna radiation parts need not always be symmetric. In addition, the number of notches in the right and left antenna radiation parts may be arbitrary.
Taking some variations as examples, the shapes of the H type antennas, or the shapes of the O type antennas, were described. However, the shapes of the antennas are not limited to them. The shape can be changed into various shapes. For example, four angle parts of the H type antenna 1 shown in FIG. 1 may also be cut to form a quadrangular shape. In addition, although it is common to the H type antenna and the O type antenna, the constriction 1 a shown in FIGS. 6A through 6D or the constriction 9 a shown in FIGS. 7A through 7D needs not be perpendicular to both side radiation parts, and accordingly the constriction 1 a or 9 a may also be obliquely arranged.
Incidentally, the present invention described above can be changed in various manners within a range of the technique thought thereof. For example, the present invention can also be applied to a ROM (Read Only Memory) type radio frequency IC tag, or a RAM (Random Access Memory) type radio frequency IC tag. Additionally, the radio frequency IC tag may also be used for any kind of purpose.
US20020135525 Aug 10, 2001 Sep 26, 2002 Morihiko Ikegaya Flat-plate antenna and electric apparatus with the same
US20040027292 Dec 13, 2001 Feb 12, 2004 Roland Gabriel Patch antenna for operating in at least two frequency ranges
JP2001053535A Title not available
US7518558 * Mar 5, 2008 Apr 14, 2009 Murata Manufacturing Co., Ltd. Wireless IC device
US7786873 * Jul 24, 2007 Aug 31, 2010 Fujitsu Limited Flexible RFID tag preventing bending stress and breakage
US7839338 * Feb 3, 2009 Nov 23, 2010 Symbol Technologies, Inc. Antenna designs for radio frequency identification (RFID) tags
US7855686 * Aug 17, 2005 Dec 21, 2010 Agency For Science, Technology And Research Compact antennas for ultra-wideband applications
US7936313 Oct 12, 2010 May 3, 2011 Symbol Technologies, Inc. Antenna designs for radio frequency identification (RFID) tags
US8098201 Jun 9, 2008 Jan 17, 2012 Electronics & Telecommunications Research Institute Radio frequency identification tag and radio frequency identification tag antenna
US8125392 * Aug 28, 2007 Feb 28, 2012 Fujikura Ltd. Antenna and electronic apparatus
US8127559 * Aug 7, 2007 Mar 6, 2012 Ryoho Freeze-Systems Corporation Core unit for refrigeration unit and refrigeration unit including the core unit
US8177138 * Apr 6, 2011 May 15, 2012 Murata Manufacturing Co., Ltd. Radio IC device
US8439272 * Jan 18, 2011 May 14, 2013 Neoid Limited Resonant circuit structure and RF tag having same
US8736031 * Sep 23, 2011 May 27, 2014 Samsung Electro-Mechanics Co., Ltd. Semiconductor package
US9460379 * Dec 30, 2015 Oct 4, 2016 Neoid Limited (Shenzhen) RF tag with resonant circuit structure
US20070256773 * May 3, 2006 Nov 8, 2007 Fu-Nan Huang Cool transfer wireless RF identification label
US20080036609 * Jul 24, 2007 Feb 14, 2008 Fujitsu Limited RFID tag
US20090140928 * Jun 9, 2008 Jun 4, 2009 Electronics And Telecommunications Research Institute Radio frequency identification tag and radio frequency identification tag antenna
US20090189822 * Feb 3, 2009 Jul 30, 2009 Symbol Technologies, Inc. Antenna Designs for Radio Frequency Identification (RFID) Tags
US20090199570 * Aug 7, 2007 Aug 13, 2009 Ryoho Freeze-Systems Corporation Core unit for refrigeration unit and refrigeration unit including the core unit
US20110025564 * Oct 12, 2010 Feb 3, 2011 Symbol Technologies, Inc. Antenna designs for radio frequency identification (rfid) tags
US20110134007 * Dec 18, 2009 Jun 9, 2011 Alan Miller Flat antenna for mobile use
US20120118977 * Jan 18, 2011 May 17, 2012 Neoid Limited Resonant circuit structure and rf tag having same
US20130015563 * Sep 23, 2011 Jan 17, 2013 Samsung Electro-Mechanics Co., Ltd. Semiconductor package
WO2010052375A1 * Nov 9, 2009 May 14, 2010 Skandinavian Kalvontekijät Oy Body part of rfid device mountable by nailing or rfid nail
U.S. Classification 340/572.7, 257/673, 29/847, 343/700.0MS, 361/748, 156/250, 29/846
International Classification H01Q7/00, G08B13/14, H05K3/02, G06K19/077, H01Q1/22, H01Q9/28, H01Q19/00, H01Q1/38
Cooperative Classification G06K19/07756, Y10T156/1052, H01Q19/00, H01Q1/2225, H01Q7/00, Y10T29/49155, Y10T29/49156, H01Q9/285, G06K19/07786
European Classification G06K19/077T2E, G06K19/077T7E, H01Q9/28B, H01Q7/00, H01Q1/22C4, H01Q19/00
Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:SAKAMA, ISAO;ASHIZAWA, MINORU;REEL/FRAME:015914/0199