Removal data storing medium having loop antenna

• US 6,243,045 B1
• Filed: 03/19/1999
• Issued: 06/05/2001
• Est. Priority Date: 03/31/1998
• Status: Expired due to Fees

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Ishibashi, Takanobu
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): NGUYEN, HOANG V
• Application Number:
  US09/272,261
• Time in Patent Office: 809 Days
• Field of Search: H01/Q.112, 343/787, 343/788, 343/741, 343/743, 343/744, 343/748, 343/866
• US Class Current: 343/741
• CPC Class Codes: G06F 13/00 Interconnection of, or transfer of information or other signals between, memories, input/output devices or central processing units interface circuits for specific input/output devices G06F3/00 ; multiprogram control therefor G06F9/46; multiprocessor systems G06F15/16
• CPC Class Codes: H01Q 1/22 by structural association with other equipment or articles
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 3/44 varying the electric or magnetic characteristics of reflecting, refracting, or diffracting devices associated with the radiating element
• CPC Class Codes: H01Q 7/005 with variable reactance for tuning the antenna

Abstract

An antenna device including a loop antenna main body having a predetermined aperture area, and a conductor element insulated from the loop antenna main body, connected to a ground potential, and formed in parallel with the loop antenna main body.

Claims

1. An antenna device comprising:

a loop antenna main body having a predetermined aperture area;

a conductor element insulated from the loop antenna main body, connected to a ground potential, and formed in parallel with the loop antenna main body;

a ferrite plate disposed across the loop antenna main body from the conductor element at a predetermined distance, the ferrite plate having a size equal to or larger than a size of the loop antenna main body; and

a copper plate electrically connected to the ferrite plate, and stuck to the ferrite plate across from the loop antenna main body.

2. An antenna device according to claim 1, further comprising:

a resonance capacitor and a Q adjusting resistor forming the loop antenna, the resonance capacitor and the Q adjusting resistor being disposed on a line of the loop antenna main body so as to be on a straight line.

3. An antenna device according to claim 1, further comprising:

an insulative board provided to support the conductor element, the board taking the shape of a rectangle having long sides and short sides, the board having a through hole for connecting an extension of the conductor element to ground of the loop antenna main body at the center of a long side.

4. An antenna device according to claim 3, further comprising:

a resonance capacitor and a Q adjusting resistor forming the loop antenna, the resonance capacitor and the Q adjusting resistor being disposed near a center of a long side of the loop antenna main body so as to be on a straight line.

5. A portable data processing apparatus comprising:

a loop antenna main body having a predetermined aperture area;

a conductor element insulated from the loop antenna main body, connected to a ground potential, and formed in parallel with the loop antenna main body;

transmitting/receiving means for transmitting and receiving predetermined information with an external data processing apparatus by transmitting and receiving radio waves via the loop antenna main body;

data processing means for conducting predetermined processing on the predetermined information transmitted and received by the transmitting/receiving means;

a ferrite plate disposed across the loop antenna main body from the conductor element at a predetermined distance, the ferrite plate having a size equal to or larger than a size of the loop antenna main body; and

a copper plate electrically connected to the ferrite plate, and stuck to the ferrite plate across from the loop antenna.

6. A portable data processing apparatus according to claim 5, further comprising:

a resonance capacitor and a Q adjusting resistor forming the loop antenna, the resonance capacitor and the Q adjusting resistor being disposed on a line of the loop antenna main body so as to be on a straight line.

7. A portable data processing apparatus according to claim 5, further comprising:

an insulative board provided to support the conductor element, the board taking the shape of a rectangle having long sides and short sides, the board having a through hole for connecting an extension of the conductor element to ground of the loop antenna main body at the center of a long side.

8. A portable data processing apparatus according to claim 7, further comprising:

a resonance capacitor and a Q adjusting resistor forming the loop antenna, the resonance capacitor and the Q adjusting resistor being disposed near a center of a long side of the loop antenna main body so as to be on a straight line.

9. An antenna device comprising:

a loop antenna main body having a predetermined aperture area;

a conductor element insulated from the loop antenna main body, connected to a ground potential, and formed in parallel with the loop antenna main body;

a magnetic substance disposed across the loop antenna main body from the conductor element at a predetermined distance, the magnetic substance having a size equal to or larger than a size of the loop antenna main body; and

a copper plate electrically connected to the magnetic substance, and stuck to the magnetic substance across from the loop antenna main body.