Optical communication Method and Apparatus

• US 20030025958A1
• Filed: 06/21/2002
• Published: 02/06/2003
• Est. Priority Date: 04/28/2000
• Status: Active Grant

• Current Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.), Sony Corporation (Sony Group Corp.)
• Original Assignee: Sharp Kabushiki Kaisha (Hon Hai Precision Industry Co., Ltd.), Sony Corporation (Sony Group Corp.)
• Inventors: Kure, Yoshinobu, Nagura, Kazuhito, Horie, Kazuyoshi, Shino, Kuninori, Masuda, Yoshifumi, Toriumi, Youichi
• Granted Patent: US 7,072,583 B2
• Time in Patent Office: Days
• US Class Current: 398/41
• CPC Class Codes: G02B 6/4214 the intermediate optical element having redirecting reflective means, e.g. mirrors, prisms for deflecting the radiation from horizontal to down- or upward direction toward a device G02B6/4246 takes precedence
• CPC Class Codes: G02B 6/4246 Bidirectionally operating package structures
• CPC Class Codes: H01L 31/165 the semiconductor sensitive to radiation being characterised by at least one potential-jump or surface barrier
• CPC Class Codes: H04B 10/40 Transceivers

Abstract

An optical communication apparatus in which bidirectional communication may be made over a sole optical fiber. A light emitting device (132) radiates light through an optical system (133) to an optical fiber (76). The light transmitted from the optical fiber (76) is received over optical system (133) by a light receiving device (136). In the optical system (133), such a relationship S−2QN≧M>S/2Q−N is set, where M is the light volume of the stray light emitted, Q is the value of a Q-value representing the communication quality as required, S is the light volume of a received signal from a communication partner and N is the sum total of the Gaussian noise.

Claims

1. An optical communication apparatus in which light for transmission and light for receipt are propagated simultaneously over a sole cable to effect bidirectional communication, comprising:

light emitting means for emitting said light for transmission;

light receipt means for receiving said light for receipt; and

light guide means for guiding said light for transmission over said cable and for guiding said light for receipt to said light receipt means, wherein

a value of a light volume M of stray light generated with respect to said light receipt means satisfies the following relationship;

S−

2QN≧

M>

S/2Q−

N

where Q is the value of a Q-value representing communication quality as required, S is light volume of a received signal from a communication partner and N is a sum total of a Gaussian noise.

2. The optical communication apparatus according to claim 1 wherein a ratio S/M, where S is the light volume of the received signal and M is the light volume of the stray light is 7% to 30%.

3. The optical communication apparatus according to claim 1 wherein a transmission speed in said optical communication is not lower than 100 Mbps.

4. The optical communication apparatus according to claim 1 wherein said cable is a plastic optical fiber.

5. The optical communication apparatus according to claim 1 wherein the sum of light volumes of the reflected light from the communication partner is 0.7% to 3.0% of the volume of the received light in said communication partner.

6. An optical communication method by an optical communication apparatus comprising light emitting means for emitting light for transmission, light receipt means for receiving light for receipt and light guide means for guiding light for transmission over said cable and for guiding said light for receipt to said light receipt means, said light for transmission and said light for receipt of substantially the same wavelength being propagated substantially simultaneously by a sole cable to effect bidirectional communication;

wherein

value of a light volume M of stray light generated with respect to said light receipt means satisfies the following relationship;

S−

2QN≧

M>

S/2Q−

N

where Q is the value of a Q-value representing communication quality as required, S is the light volume of a received signal from a communication partner and N is a sum total of a Gaussian noise.

7. An optical communication apparatus in which light for transmission and light for receipt of substantially a same wavelength are propagated simultaneously over a sole cable to effect bidirectional communication, comprising:

light emitting means for emitting said light for transmission;

light receipt means for receiving said light for receipt;

light guide means for guiding said light for transmission over said cable and for guiding said light for receipt to said light receipt means, and

controlling means for controlling said light emitting means and the light receipt means, said controlling means allowing for processing of a signal corresponding to said light for receipt received by said light receipt means in a state in which said light for transmission is emitted by said light emitting means and propagated over said cable, said controlling means allowing for processing for transmission of a signal by said light for transmission emitted by said light emitting means in a state in which the light for receipt propagated over said cable is being received by said light receipt means.

8. An optical communication method for an optical communication apparatus comprising light emitting means for emitting light for transmission, light receipt means for receiving light for receipt and light guide means for guiding light for transmission to said cable and for guiding said light for receipt to said light receipt means, in which said light for transmission and said light for receipt of substantially a same wavelength are propagated simultaneously over a sole cable to effect bidirectional communication;

said optical communication method comprising the steps of;

allowing for processing of a signal corresponding to said light for receipt received by said light receipt means in a state in which said light for transmission is emitted by said light emitting means and propagated over said cable; and

allowing for processing for transmission of a signal by said light for transmission emitted by said light emitting means in a state in which the light for receipt propagated over said cable is being received by said light receipt means.