Portable telephone

• US 6,785,519 B2
• Filed: 12/27/2001
• Issued: 08/31/2004
• Est. Priority Date: 12/27/2000
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Okayama, Katsumi, Toyoda, Junichi
• Primary Examiner(s): Milord, Marceau
• Application Number:
  US10/034,407
• Publication Number:
  US 20020160725A1
• Time in Patent Office: 978 Days
• Field of Search: 455/90.1, 455/300, 455/301, 455/90.3, 455/575.1, 455/569.1, 455/550.1, 455/106, 455/575.8, 455/575.7, 455/575.5, 455/117, 455/128, 455/83, 343/702, 343/841
• US Class Current: 455/90.1
• CPC Class Codes: H01Q 1/245 with means for shaping the antenna pattern, e.g. in order to protect user against rf exposure
• CPC Class Codes: H01Q 17/001 for modifying the directional characteristic of an aerial
• CPC Class Codes: H04B 1/3838 Arrangements for reducing RF exposure to the user, e.g. by changing the shape of the transceiver while in use

Abstract

The portable telephone capable of more effectively reducing the electromagnetic energy to be radiated therefrom and absorbed by the human body during its use is provided. The portable telephone is comprised of: an antenna; a microphone; a transmitting circuit for modulating a first audio signal to produce a first radio signal, and transmitting the same; a receiving circuit for demodulating a second radio signal received via the antenna, and reproducing a second audio signal; a receiver for outputting an audio sound corresponding to the second audio signal; a printed circuit board on which the receiving and the transmitting circuits are mounted; a shield case surrounding the printed circuit board so as to suppress the electromagnetic interference between the printed circuit board and the antenna; the housing for accommodating the shield case and so on; the electromagnetic wave absorption layer including a magnetic loss material, formed at least in a part between the shield case and the housing; and the electromagnetic wave reflection layer including a magnetic reflection material, formed between the housing and the electromagnetic wave absorption layer.

Claims

1. A portable telephone comprising:

an antenna;

a microphone for generating a first audio signal corresponding to a sound entered to said microphone;

a transmitting circuit for modulating said first audio signal from said microphone to generate a first radio signal, and transmitting said first radio signal via said antenna;

a receiving circuit for receiving a second radio signal which is modulated from a second audio signal via said antenna, and demodulating said second radio signal to reproduce said second audio signal;

a receiver for outputting a sound corresponding to said second audio signal from said receiving circuit;

a printed circuit board on which said receiving circuit and said transmitting circuit are mounted;

a shield case which surrounds said printed circuit board for suppressing an electromagnetic interference between said printed circuit board and said antenna, and has an electrical conductivity at least on its surface;

a housing for accommodating said microphone, said receiver and said shield case;

an electromagnetic wave absorption layer containing a magnetic loss material, provided at least in a portion between said shield case and said housing; and

an electromagnetic wave reflection layer containing a magnetic reflection material, provided between said housing and said electromagnetic wave absorption layer.

2. The portable telephone according to claim 1, wherein:

said electromagnetic wave absorption layer is formed in contact with said shield case, and adjacent to said receiver; and

said electromagnetic wave reflection layer is formed as laminated on said electromagnetic wave absorption layer.

3. The portable telephone according to claim 2, wherein said electromagnetic wave absorption layer is pasted on said shield case with an adhesive.

4. The portable telephone according to claim 1, wherein:

said electromagnetic wave reflection layer is formed in contact with said housing, in the vicinity of said receiver, and

said electromagnetic wave absorption layer is laminated on said electromagnetic wave reflection layer.

5. The portable telephone according to claim 3, wherein said electromagnetic wave reflection layer is pasted on said housing with an adhesive in the vicinity of said receiver.

6. The portable telephone according to claim 1, wherein:

said electromagnetic wave absorption layer comprises a material having a complex magnetic permeability a real part of which is small while an imaginary part of which is large at frequencies of said first and said second radio signals; and

said electromagnetic wave reflection layer comprises a material having a complex magnetic permeability a real part of which is large while an imaginary part of which is small at frequencies of said first and said second radio signals.

7. The portable telephone according to claim 6, wherein said electromagnetic wave absorption layer includes a layer which is molded after mixing said magnetic loss material with a synthetic resin.

8. The portable telephone according to claim 7, wherein said magnetic loss material contains at least one selected from the group of materials consisting of ferrite, Permalloy, Sendust, stainless steel, silicon steel and ferro-amorphous alloy.

9. The portable telephone according to claim 6, wherein said electromagnetic wave reflection layer includes a layer which is molded after mixing said magnetic reflection material with a synthetic resin.

10. The portable telephone according to claim 9, wherein said magnetic reflection material contains carbonyl iron.

11. The portable telephone according to claim 9, wherein said magnetic reflection material contains ferrite.

12. The portable telephone according to claim 1, wherein said shield case comprises a case made of an insulating material, and a conductive layer formed on a surface of said case.

13. The portable telephone according to claim 1, wherein an interface between said electromagnetic wave absorption layer and said electromagnetic wave reflection layer is bonded with adhesive.

14. The portable telephone according to claim 1, wherein said electromagnetic wave absorption layer and said electromagnetic wave reflection layer are molded and laminated as an integral lamination film.