Fiber optic network using space and wavelength multiplexed data channel arrays

• US 6,097,519 A
• Filed: 01/14/1999
• Issued: 08/01/2000
• Est. Priority Date: 08/01/1996
• Status: Expired due to Fees

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Krishnamoorthy, Ashok V., Knox, Wayne H., Ford, Joseph E., Miller, David A. B., Nuss, Martin C.
• Primary Examiner(s): NEGASH, KINFE MICHAEL
• Application Number:
  US09/231,418
• Time in Patent Office: 565 Days
• Field of Search: 359/124, 359/130-131, 359/173, 385/24, 385/37
• US Class Current: 398/1
• CPC Class Codes: H04B 10/506 Multiwavelength transmitters
• CPC Class Codes: H04J 14/02 Wavelength-division multiplex systems

Abstract

A network for multi-bit word parallel communication between optoelectronic chips on a two dimensional array of optical input and output channels carried on a single dimension of optical fibers. Each bit of a word is carried on a different wavelength and the multiple wavelengths carrying a word are wavelength multiplexed onto a single optical fiber. Multiple fibers can be joined into a one dimensional array of fibers. A transceiver for transmitting and receiving along the optical data channels comprises an array of modulators powered by individual wavelength light beams, either from individual monochromatic light sources and a light beam from a single broadband light source made to pass through a diffraction grating. The modulators are positioned so that each modulator reflects a different wavelength light beam, thereby providing multiple optical channels. Alternatively, multiple wavelengths are generated from CMOS integrated light sources. These multiple optical channels are then collimated and guided into one single mode fiber or multiple multimode fibers at its transmitting end. At the receiving end a diffraction grating is used to separate the distinct data channels by their individual wavelengths. The multiple wavelengths are then caused to fall on an array of optical detectors spaced according to the individual wavelengths to be detected. By constructing a one dimensional array of these fibers, a two dimensional array of optical data channels is realized. The size of the array is determined by the number of fibers and the number of distinct wavelengths combined in each fiber.

Claims

1. A two dimensional array of optical data channels, comprising:

a plurality of optical fibers, each of said plurality of optical fibers carrying data on multiple single wavelength channels as wavelength division multiplexed data;

means for dispersing said multiple single wavelength channels along two dimensions; and

means for collecting said two dimensional array of multiple single wavelength channels.

2. A two dimensional array of optical data channels according to claim 1 wherein said means for dispersing comprises one or more diffraction gratings.

3. A two dimensional array of optical data channels according to claim 1 wherein said means for collecting comprises one or more collimation lenses.

4. A two dimensional array of optical data channels according to claim 1 wherein said wavelength division multiplexed channel of each of said plurality of optical fibers are powered by a broadband light beam.

5. A two dimensional array of optical data channels according to claim 4 wherein said broadband light beam has a given diameter further comprising:

means for expanding said diameter of said broadband light beam; and

a filter placed at a predetermined angle to said expanded broadband light beam for separating two or more wavelengths with a desired spacing therebetween from said expanded broadband light beam.

6. A two dimensional array of optical data channels according to claim 5 wherein said filter comprises an etalon having a dielectric substrate with front and back sides, said front and back sides being covered with partially reflective metal or dielectric coating.

7. A method for providing a two dimensional array of optical data channels, comprising the steps of:

collecting a plurality of optical fibers each of said optical fibers carrying multiple single wavelength channels as a wavelength division multiplexed channel; and

dispersing each of said wavelength division multiplexed channels thereby providing optical channels along a first dimension and optical channels along a second dimension where said second dimension is not parallel to said first dimension.

8. A method according to claim 7 further comprising the steps of:

powering said multiple wavelengths of said wavelength division multiplexed channel by guiding a single broadband light beam through a diffraction grating so as to disperse said broadband light into its constituent single wavelength light beams;

modulating each of said single wavelength light beams according to a time varying pattern reflecting data desired to be transmitted; and

collecting said plurality of reflected and modulated single wavelength light beams into a single optical fiber.

9. A method according to claim 7 wherein said wavelength division multiplexed channel of each of said plurality of optical fibers are powered by a broadband light beam.

10. A method according to claim 8 wherein said broadband light beam has a given diameter and said powering step further comprises the steps of:

expanding said given diameter of said broadband light beam;

filtering said expanded broadband light beam such that two or more wavelengths of said broadband light beam having a desired spacing there between, are separated from said expanded broadband light beam; and

collecting said separated wavelengths into a single optical power fiber.

11. A method according to claim 10 wherein filtering step involves an etalon having a dielectric substrate with front and back sides, said front and back sides being covered with partially reflective metal or dielectric coating on both sides.