Electronic Device That is Worn on the Wrist

• US 20110102274A1
• Filed: 10/27/2010
• Published: 05/05/2011
• Est. Priority Date: 10/30/2009
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Fujisawa, Teruhiko
• Granted Patent: US 9,130,272 B2
• Time in Patent Office: Days
• US Class Current: 343/702
• CPC Class Codes: G04G 5/002 brought into action by radio
• CPC Class Codes: G04R 60/10 inside cases
• CPC Class Codes: H01Q 1/273 Adaptation for carrying or wearing by persons or animals
• CPC Class Codes: H01Q 1/40 Radiating elements coated with or embedded in protective material
• CPC Class Codes: H01Q 7/00 Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Abstract

A wrist-worn electronic device includes an antenna that receives externally transmitted radio signals; a case of which at least part is made of a non-conductive material; an information display unit that is housed inside the case, is flat, and is made of a non-conductive material; a back cover that is attached to the case and is made of a conductive material; and a reception unit that is positioned and housed inside the case between the information display unit and the back cover, and processes a reception signal based on radio signals received by the antenna. The antenna has an antenna electrode that is disposed and formed as a line around the outside of the information display unit. The back cover is connected to the ground potential of the reception unit and reflects the radio signals.

Claims

1. A wrist-worn electronic device, comprising:

an antenna that receives externally transmitted radio signals;

a case of which at least part is made of a non-conductive material;

an information display unit that is housed inside the case, is flat, and is made of a non-conductive material;

a back cover that is attached to the case and is made of a conductive material; and

a reception unit that is positioned and housed inside the case between the information display unit and the back cover, and processes a reception signal based on radio signals received by the antenna;

wherein the antenna has an antenna electrode that is disposed and formed as a line around the outside of the information display unit; and

the back cover is connected to the ground potential of the reception unit and reflects the radio signals.

2. The wrist-worn electronic device described in claim 1, wherein:

the back cover is made with a larger outside dimension than the outside dimension of the antenna electrode.

3. The wrist-worn electronic device described in claim 1, further comprising:

a dial ring that is disposed around the outside of the information display unit and is formed in a ring shape from a non-conductive material; and

a bezel that is disposed on the outside circumference side of the dial ring and is formed in a ring shape from a non-conductive material;

wherein the antenna is disposed between and covered by the dial ring and the bezel.

4. The wrist-worn electronic device described in claim 1, wherein:

the antenna has an annular dielectric substrate to which the antenna electrode is disposed; and

the antenna electrode is formed with a circumferential length approximately equal to one wavelength of the wavelength of the radio signal after wavelength shortening by the dielectric substrate.

5. The wrist-worn electronic device described in claim 1, wherein:

the antenna has an annular dielectric substrate to which the antenna electrode is disposed;

the antenna electrode has an annular main antenna unit disposed to the top of the dielectric substrate on the opposite side as the bottom side thereof facing the back cover, and a power supply unit that branches from at least one junction rendered in part of the main antenna unit and is disposed to the dielectric substrate; and

the wrist-worn electronic device also has a connection member that is housed in the case, contacts the power supply unit, and transmits the reception signal to the reception unit.

6. The wrist-worn electronic device described in claim 1, wherein:

the information display unit is a dial or a display panel.