Antenna device, card information medium, electronic apparatus, and method for manufacturing antenna device
An antenna device includes a coil including first linear conductors on a first principal surface side of a multilayer body, second linear conductors on a second principal surface side, first end-surface conductors and second end-surface conductors disposed on end surfaces. Each of the first linear conductors includes a first main portion, a first end portion, and a second end portion. Each of the second linear conductors includes a second main portion, a third end portion, and a fourth end portion. The width of each of the first end-surface conductors is smaller than the width of the first main portion and the width of the second main portion. The width of each of the second end-surface conductors is smaller than the width of the first main portion and the width of the second main portion.
1. An antenna device comprising:
a multilayer body including a plurality of insulating layers laminated in a lamination direction; and
a coil including a plurality of linear conductors and end-surface conductors, each of the linear conductors being disposed on a surface of the insulating layers and including two end portions and a main portion connecting the two end portions, the two end portions being positioned on outer edges of the insulating layers;
each of the end-surface conductors being disposed on an end surface parallel or substantially parallel to the lamination direction, the end-surface conductor connecting the two end portions in the linear conductors in the lamination direction; wherein
a width of the end-surface conductor is smaller than a width of the main portion, and an interval between the end-surface conductors adjacent to each other is wider than an interval between the main portions being next to each other in a direction parallel or substantially parallel with respect to the surfaces of the insulating layers and the end surface of the multilayer body.
2. The antenna device according to claim 1 , wherein in the direction parallel or substantially parallel with respect to the surfaces of the insulating layers and the end surface of the multilayer body, a line width of each of the two end portions is smaller than a line width of the main portion.
3. The antenna device according to claim 2 , wherein each of the two end portions has a line width that gradually decreases as a distance from the main portion increases.
4. The antenna device according to claim 2 , wherein in each of the two end portions, a line width of a portion that is adjacent to the main portion is larger than a line width of a portion that is remote from the main portion.
5. The antenna device according to claim 1 , wherein a width of a connection portion between the end-surface conductor and each of the two end portions differs from the line width of the end-surface conductor.
6. The antenna device according to claim 5 , wherein the connection portion between the end-surface conductor and each of the two end portions is located inside the edges of the insulating layers.
7. The antenna device according to claim 1 , wherein the end-surface conductor includes a plurality of interlayer connection conductors linked together.
8. The antenna device according to claim 7 , wherein each of the interlayer connection conductors has a circular or oval cross-sectional shape.
9. A card information medium comprising:
an antenna; and
a memory; wherein
the antenna includes:
a multilayer body including a plurality of insulating layers laminated in a lamination direction; and
a coil including a plurality of linear conductors and end-surface conductors, each of the linear conductors being disposed on a surface of the insulating layers and including two end portions and a main portion connecting the two end portion, the two end portions being positioned on outer edges of the insulating layers, each of the end-surface conductors being disposed on an end surface parallel or substantially parallel to the lamination direction, the end-surface conductor connecting the two end portions in the linear conductors in the lamination direction; and
a width of the end-surface conductor is smaller than a width of the main portion, and an interval between the end-surface conductors adjacent to each other is wider than an interval between the main portions being next to each other in a direction parallel or substantially parallel with respect to the surfaces of the insulating layers and the end surface of the multilayer body.
10. An electronic apparatus comprising:
an antenna; and
a casing that houses the antenna; wherein
the antenna includes:
a multilayer body including a plurality of insulating layers laminated in a lamination direction; and
a coil including a plurality of linear conductors and end-surface conductors, each of the linear conductors being disposed on a surface of the insulating layers and including two end portions and a main portion connecting the two end portion, the two end portions being positioned on outer edges of the insulating layers, each of the end-surface conductors being disposed on an end surface parallel or substantially parallel to a lamination direction in which the insulating layers are laminated in the multilayer body, the end-surface conductor connecting the two end portions in the linear conductors in the lamination direction; and
parallel or substantially parallel to a width of the end-surface conductor is smaller than a width of the main portion, and an interval between the end-surface conductors adjacent to each other is wider than an interval between the main portions being next to each other in a direction parallel or substantially parallel with respect to the surface of the insulating layers and the end surface of the multilayer body.
11. A method for manufacturing an antenna device, the antenna device including:
a multilayer body including a plurality of insulating layers laminated in lamination direction; and
a coil including a plurality of linear conductors and end-surface conductors, each of the linear conductors being disposed on a surface of the insulating layers and including two end portions and a main portion connecting the two end portion, the two end portions being positioned on outer edges of the insulating layers, each of the end-surface conductors being disposed on an end surface parallel or substantially parallel to a lamination direction in which the insulating layers are laminated in the multilayer body, the end-surface conductor connecting the two end portions in the linear conductors in the lamination direction;
the method comprising the steps of:
forming a paste pattern corresponding to the plurality of linear conductors on the insulating layers;
forming through holes in the plurality of insulating layers and filling the through holes with conductive paste for the end-surface conductors;
laminating the plurality of insulating layers and firing them; and
cutting the multilayer body along a line passing through the plurality of end-surface conductor; wherein
a width of each of the end-surface conductors is smaller than a width of the main portions.
12. The antenna device according to claim 1 , further comprising outer connection electrodes disposed on a principal surface of the multilayer body, the outer connection electrodes being electrically connected to ends of the coil.
13. The card information medium according to claim 9 , further comprising outer connection electrodes disposed on a principal surface of the multilayer body, the outer connection electrodes being electrically connected to ends of the coil.
14. The electronic apparatus according to claim 10 , further comprising outer connection electrodes disposed on a principal surface of the multilayer body, the outer connection electrodes being electrically connected to ends of the coil.
15. The method for manufacturing an antenna device according to claim 11 , further comprising a step of forming outer connection electrodes on a principal surface of the multilayer body, the outer connection electrodes being electrically connected to ends of the coil.
16. The antenna device according to claim 1 , wherein the linear conductors on one of the insulating layers are angled in a direction different from a direction in which the linear conductors on another one of the insulating layers are angled.
17. The card information medium according to claim 9 , wherein the linear conductors on one of the insulating layers are angled in a direction different from a direction in which the linear conductors on another one of the insulating layers are angled.
18. The electronic apparatus according to claim 10 , wherein the linear conductors on one of the insulating layers are angled in a direction different from a direction in which the linear conductors on another one of the insulating layers are angled.
19. The method for manufacturing an antenna device according to claim 11 , wherein the linear conductors on one of the insulating layers are angled in a direction different from a direction in which the linear conductors on another one of the insulating layers are angled.
20. The card information medium according to claim 9 , wherein the end-surface conductor includes a plurality of interlayer connection conductors linked together.