Bidirectional optical transmission and reception module

• US 5,400,419 A
• Filed: 12/03/1993
• Issued: 03/21/1995
• Est. Priority Date: 12/03/1992
• Status: Expired due to Fees

• Current Assignee: Infineon Technologies Fiber Optics GmbH (Infineon Technologies AG)
• Original Assignee: Siemens AG
• Inventors: Heinen, Jochen
• Primary Examiner(s): Lee, John D.
• Application Number:
  US08/161,666
• Time in Patent Office: 473 Days
• Field of Search: 385/14, 385/24, 385/129-132, 359/113, 359/114, 359/127, 359/133, 359/138, 359/152, 359/154, 359/159, 359/168-170
• US Class Current: 385/14
• CPC Class Codes: G02B 6/4246 Bidirectionally operating package structures
• CPC Class Codes: H04B 10/40 Transceivers

Abstract

A bidirectional optical transmission and reception module includes a substrate having one surface provided with waveguides and mirrors for deflecting radiation into the substrate and on an opposite surface of the substrate is provided a laser diode serving as a transmitter, a photodiode as a receiver, and a terminal for an optical fiber, each opposite the mirrors on the waveguides. Optical connections between the optical fiber and the laser diode and between the optical fiber and the photodiode are carried out through the substrate and via the waveguides. An optical coupler is also provided between the waveguides.

Claims

1. An apparatus for bidirectional optical transmission and reception, comprising:

a substrate of a material which is transmissive to optical radiation, said substrate having first and second surfaces;

at least two strip-shaped waveguides on said second surface of said substrate, said at least two strip-shaped waveguides being arranged to provide optical waveguidance substantially parallel to said second surface of said substrate;

mirrors at ends of said at least two strip-shaped waveguides, said mirrors being angled to reflect optical radiation between said at least two strip-shaped waveguides and said substrate;

a terminal connectible to an external waveguide and mounted on said first surface of said substrate, said terminal being aligned such that radiation proceeding from said external waveguide proceeds through said substrate to one of said mirrors on one of said at least two strip-shaped waveguides;

at least one laser diode on said first surface of said substrate and aligned such that radiation proceeding from said at least one laser diode proceeds through said substrate to one of said mirrors on one of said at least two strip-shaped waveguides;

a photodiode on said first surface of said substrate and aligned to receive optical radiation reflected by one of said mirrors from one of said at least two strip-shaped waveguides; and

at least one optical coupler between said at least two strip-shaped waveguides to provide optical communication between said terminal and said at least one laser diode and said photodiode.

2. An apparatus as claimed in claim 1, further comprising:

a further photodiode on said first surface of said substrate and arranged to receive optical radiation from one of said mirrors on one of said at least two strip-shaped waveguides which optical radiation has been emitted by said at least one laser diode and thereby serve as a monitor diode.

3. An apparatus as claimed in claim 2, wherein said photodiode and said further photodiode are optically connected through a same one of said at least two strip-shaped waveguides.

4. An apparatus as claimed in claim 1, wherein said at least one laser diode and said terminal are optically connected through a same one of said at least two strip-shaped waveguides:

5. An apparatus as claimed in claim 1, further comprising:

a filter layer on said first surface of said substrate, said filter layer including a first filter between said at least one laser diode and said substrate and a second filter between said photodiode and said substrate, said first filter being non-transmissive for a wavelength of radiation to be received by said photodiode, and said second filter being non-transmissive for a wavelength of optical radiation emitted by said at least one laser diode.

6. An apparatus as claimed in claim 1, further comprising:

a metal layer on said first surface of said substrate between said at least one laser diode and said substrate, said metal layer defining openings to permit optical radiation to pass therethrough unimpeded between said at least one laser diode and said substrate.

7. An apparatus as claimed in claim 1, wherein said at least one laser diode and said photodiode are integrated in a layer sequence grown onto said substrate.

8. A bidirectional optical module for connection to a terminal end of an optical fiber, comprising:

a substrate of a semiconductor material which is transparent to optical radiation carried on the optical fiber, said substrate having a first surface and a second surface and defining a location on said first surface for optical connection of the optical fiber;

a laser diode on said first surface of said substrate arranged to transmit optical radiation into said substrate;

a photodiode on said first surface of said substrate and arranged to receive radiation transmitted from said substrate;

at least one optical waveguide on said second surface of said substrate, said at least one optical waveguide including a terminal end mirror opposite said laser diode to reflect light received through said substrate from said laser diode into said at least one waveguide, a mirror opposite said location for connecting the optical fiber to transmit optical radiation carried in the waveguide through the substrate and into the optical fiber, and a mirror at a location opposite said photodiode to reflect optical radiation carried in said waveguide through said substrate into said photodiode, wherein said at least one waveguide comprises two waveguides, and

an optical coupler between said two waveguides to optically connect optical radiation between said two waveguides.