Antenna and timepiece
An antenna-equipped cover glass for a wristwatch includes: a first insulating layer that includes a transparent insulator; a first electrode layer connected to a bottom surface of the first insulating layer, the first electrode layer having a first transparent electrode surrounded by an insulating pattern formed in a region therein; a second insulating layer connected to a bottom surface of the first electrode layer; and a second electrode layer connected to a bottom surface of the second insulating layer, the second electrode layer having a second transparent electrode surrounded by an insulating pattern formed in a region therein.
1. A timepiece, comprising:
an antenna that comprises:
a first insulating layer that includes a transparent insulator;
a first electrode layer connected to a bottom surface of the first insulating layer, the first electrode layer having a first transparent electrode at least partially surrounded by an insulating pattern formed in a region of the first electrode layer;
a second insulating layer connected to a bottom surface of the first electrode layer; and
a second electrode layer connected to a bottom surface of the second insulating layer, the second electrode layer having a second transparent electrode at least partially surrounded by an insulating pattern formed in a region of the second electrode layer;
a circuit board on which a communication circuit that performs communication via the antenna is mounted;
a dial plate arranged between the antenna and the circuit board; and
a connector,
wherein the connector is arranged between the antenna and the circuit board, and
wherein the connector includes a first terminal that connects to the first transparent electrode and a second terminal that connects to the second transparent electrode.
2. The timepiece according to claim 1 , wherein the second insulating layer includes a dielectric having a permittivity that changes in accordance with a DC voltage applied to the first electrode layer and the second electrode layer.
3. The timepiece according to claim 1 , wherein the insulating pattern in the first electrode layer is a filler formed in a region of the first electrode layer in which the first transparent electrode is not formed.
4. The timepiece according to claim 3 ,
wherein a transmittance of the filler in the first electrode layer is within ±40% of a transmittance of the first transparent electrode, and
wherein a refractive index of the filler in the first electrode layer is within ±40% of a refractive index of the first transparent electrode.
5. The timepiece according to claim 1 , wherein the first insulating layer includes:
a transparent plate; and
an antireflective film formed on a surface of the transparent plate.
6. The timepiece according to claim 2 , wherein the first insulating layer includes:
a transparent plate; and
an antireflective film formed on a surface of the transparent plate.
7. The timepiece according to claim 3 , wherein the first insulating layer includes:
a transparent plate; and
an antireflective film formed on a surface of the transparent plate.
8. The timepiece according to claim 4 , wherein the first insulating layer includes:
a transparent plate; and
an antireflective film formed on a surface of the transparent plate.
9. The timepiece according to claim 1 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
10. The timepiece according to claim 2 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
11. The timepiece according to claim 3 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
12. The timepiece according to claim 4 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
13. The timepiece according to claim 5 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
14. The timepiece according to claim 6 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
15. The timepiece according to claim 7 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.
16. The timepiece according to claim 8 ,
wherein the second insulating layer and the second transparent electrode have cutout portions, and
wherein the cutout portions expose the first transparent electrode.