Optical transmission-reception apparatus

• US 6,188,495 B1
• Filed: 11/21/1997
• Issued: 02/13/2001
• Est. Priority Date: 11/25/1996
• Status: Expired due to Fees

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Toriumi, Yoichi, Inoue, Tatsuo
• Primary Examiner(s): Pascal, Leslie
• Assistant Examiner(s): Phan, Hanh
• Application Number:
  US08/975,908
• Time in Patent Office: 1,180 Days
• Field of Search: 359/152, 359/153, 359/163, 359/156, 359/122
• US Class Current: 398/139
• 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: H04B 10/43 using a single component as both light source and receiver, e.g. using a photoemitter as a photoreceiver

Abstract

A transmission optical signal emitted from a laser diode is introduced in an S-polarized state to a polarization-reflection film formed on an inclined surface of a prism. This transmission optical signal is in a light quantity that is reflected by the polarization-reflection film to enter an optical fiber. With this configuration, an optical transmission-reception apparatus for a single-core bi-directional optical communication circuit enables an enhancement of the efficiency of introduction of the transmission optical signal into the optical fiber constituting the optical communication circuit so that a sufficient performance and reliability of the optical communication circuit is realized without increasing the light quantity emitted from the laser diode which outputs the transmission optical signal.

Claims

1. An optical transmission-reception apparatus comprising:

an optical transmission medium connection block to which an optical transmission medium is connected for transmitting to a second end face a first optical signal inputted from a first end face;

a light-emitting element for emitting said first optical signal which is in a linearly polarized state;

a beam splitting film provided on an optical path starting at said light-emitting element and reaching said first end face of said optical transmission medium, so as to split a second optical signal emitted from the first end face of said optical transmission medium, a first polarization component of said second optical signal passing through said film, a second polarization component of said second optical signal being reflected by said film, approximately 100% of said first optical signal continuing on said optical path toward said first end face of said optical transmission medium after said beam splitter; and

a light-receiving element for receiving at least one of said first and second polarization components of said second optical signal via said beam splitting film.

2. An optical transmission-reception apparatus as claimed in claim 1, wherein said beam splitting film has such a characteristic that an S-polarized optical signal is reflected and a P-polarized optical signal passes through.

3. An optical transmission-reception apparatus as claimed in claim 2, wherein said light-emitting element emits an S-polarized optical signal.

4. An optical transmission-reception apparatus as claimed in claim 2, wherein said light-emitting element emits a P-polarized optical signal.

5. An optical transmission-reception apparatus as claimed in claim 1, wherein said light-emitting element and said light-receiving element are arranged on a single substrate, and said beam splitting film is formed on a surface of a prism arranged on said substrate.

6. An optical transmission-reception apparatus as claimed in claim 1, wherein said optical transmission medium is an optical fiber cable.

7. An optical transmission-reception apparatus as claimed in claim 1, said apparatus further comprising a lens arranged on an optical path between said beam splitting film and the first end face of said optical transmission medium connected to said optical transmission medium connection block so that said first optical signal is introduced to said first end face of said optical transmission medium.

8. The apparatus of claim 1, wherein the first polarization component is substantially orthogonal to the second polarization component.

9. An optical transmission-reception apparatus comprising:

an optical transmission medium connection block to which an optical transmission medium is connected for transmitting to a second end face a first optical signal inputted from a first end face;

a light-emitting element for emitting said first optical signal which is in a linearly polarized state;

a beam splitting film provided on an optical path starting at said light-emitting element and reaching said first end face of said optical transmission medium, so as to split a second optical signal emitted from the first end face of said optical transmission medium; and

a light-receiving element for receiving at least one polarization component of said second optical signal via said beam splitting film,

wherein said beam splitting film has such a characteristic that an S-polarized optical signal is approximately 100% reflected and a P-polarized optical signal is approximately 100% transmitted, such that approximately 100% of said first optical signal continues on said optical path toward said first end face of said optical transmission medium after said beam splitter.

10. An optical transmission-reception apparatus as claimed in claim 9, wherein said light-emitting element emits an S-polarized optical signal.

11. An optical transmission-reception apparatus as claimed in claim 9, wherein said light-emitting element emits a P-polarized optical signal.

12. An optical transmission-reception apparatus comprising:

an optical transmission medium connection block to which an optical transmission medium is connected for transmitting to a second end face a first optical signal inputted from a first end face;

a light-emitting element for emitting said first optical signal which is in a linearly polarized state;

a beam splitting film provided on an optical path starting at said light-emitting element and reaching said first end face of said optical transmission medium, so as to split a second optical signal emitted from the first end face of said optical transmission medium and reaching said light-emitting element; and

a light-receiving element for receiving said second optical signal via said beam splitting film, wherein said light-emitting element and said light-receiving element are arranged on a single surface of a substrate, and said beam splitting film is formed on a surface of a prism arranged on said substrate.

13. An optical transmission-reception apparatus comprising:

an optical transmission medium connection block to which an optical transmission medium is connected for transmitting to a second end face a first optical signal inputted from a first end face;

a light-emitting element for emitting said first optical signal which is in a linearly polarized state;

a beam splitting film provided on an optical path starting at said light-emitting element and reaching said first end face of said optical transmission medium, so as to split a second optical signal emitted from the first end face of said optical transmission medium and reaching said light-emitting element;

a light-receiving element for receiving said second optical signal via said beam splitting film; and

a lens arranged on an optical path between said beam splitting film and the first end face of said optical transmission medium connected to said optical transmission medium connection block so that said first optical signal is introduced to said first end face of said optical transmission medium, wherein said lens is engaged to be held in a through hole formed in an upper plane of a frame shaped housing.

14. An optical transmission-reception apparatus comprising:

means for optically transmitting a first optical signal to a second end face inputted from a first end face;

means for emitting said first optical signal which is in a linearly polarized state;

means for splitting a second optical signal emitted from the first end face of said optical transmitting means, approximately 100% of a first polarization component of said second optical signal passing through said splitting means, approximately 100% of a second polarization component of said second optical signal being reflected by said splitting means, approximately 100% of said first optical signal continuing on an optical path including said splitting means toward said first end face of said optical transmitting means after said splitting means; and

means for receiving at least one of said first and second polarization components of said second optical signal via said splitting means.

15. An optical transmission-reception apparatus comprising:

means for optically transmitting a first optical signal to a second end face inputted from a first end face;

means for emitting said first optical signal which is in a linearly polarized state;

means for splitting a second optical signal emitted from the first end face of said optically transmitting means; and

means for detecting at least a first polarization component of said second optical signal via said splitting means,

wherein said splitting means has such a characteristic that a first polarization component is approximately 100% reflected and a second polarization component is approximately 100% transmitted, such that approximately 100% of said first optical signal continues on said optical path toward said first end face of said optically transmitting means after said splitting means.