Tunable optical routing systems

• US 7,257,288 B1
• Filed: 04/25/2005
• Issued: 08/14/2007
• Est. Priority Date: 04/23/2004
• Status: Active Grant

• Current Assignee: Molex LLC (KOCH Industries Incorporated)
• Original Assignee: Nistica, Inc. (KOCH Industries Incorporated)
• Inventors: Koeppen, Christopher S., Strasser, Thomas Andrew, Wagener, Jefferson L.
• Primary Examiner(s): PAK, SUNG H
• Application Number:
  US11/113,822
• Time in Patent Office: 841 Days
• Field of Search: None
• US Class Current: 385/24
• CPC Class Codes: G02B 6/2706 as bulk elements, i.e. free space arrangements external to a light guide, e.g. polarising beam splitters
• CPC Class Codes: G02B 6/2931 Diffractive element operating in reflection
• CPC Class Codes: G02B 6/29311 Diffractive element operating in transmission
• CPC Class Codes: G02B 6/29313 characterised by means for controlling the position or direction of light incident to or leaving the diffractive element, e.g. for varying the wavelength response switching G02B6/35
• CPC Class Codes: G02B 6/29314 by moving or modifying the diffractive element, e.g. deforming
• CPC Class Codes: G02B 6/29383 Adding and dropping

Abstract

An optical wavelength routing device utilizes a free space optical beam propagating therethrough is provided. The device includes at least one optical fiber input, at least one optical fiber output, an optical element having an actuator with at least one tilt axis and a diffraction element having a surface thereon. The device also includes an optical beam-splitting element having spatially varying optical properties. An optical beam transfer arrangement is positioned between the optical element and the diffraction element such that tilt actuation of the optical element elicits a proportional change in an angle of incidence of the optical beam onto the diffraction element, wherein the center of rotation for the angular change is the surface of the diffraction element. Optical routing between the fiber input and the fiber output can be configured by the positioning of the optical element.

Claims

1. An optical wavelength routing device utilizing a free space optical beam propagating therethrough, comprising:

a. at least one optical fiber input;

b. at least one optical fiber output;

c. an optical element having an actuator with at least one tilt axis;

d. a diffraction element having a surface thereon;

e. an optical beam-splitting element having spatially varying optical properties;

f. an optical beam transfer arrangement positioned between the optical element and the diffraction element such that tilt actuation of the optical element elicits a proportional change in an angle of incidence of the optical beam onto the diffraction element, wherein the center of rotation for the angular change is the surface of the diffraction element;

wherein optical routing between the fiber input and the fiber output can be configured by the positioning of the optical element.

2. The optical wavelength routing device according to claim 1 wherein the optical beam actuator has two tilt axes.

3. The optical wavelength routing device according to claim 2 where the two tilt axes enable substantially independent control of both a center wavelength and a drop bandwidth of the optical beam diverted from the primary output port.

4. The optical wavelength routing device according to claim 2 where the two tilt axes enable substantially independent control of both a center wavelength and power level of routed wavelengths.

5. The optical wavelength routing device according to claim 1 where the optical beam transfer arrangement is a lens-based telescope.

6. The optical wavelength routing device according to claim 1 further comprising at least 2 optical fiber outputs.

7. The optical wavelength routing device according to claim 1 where the optical element is a 2 axis MEMs tilt mirror.

8. The optical wavelength routing device according to claim 1 where the diffraction element is a reflective diffraction grating.

9. The optical wavelength routing device according to claim 1 where the diffraction element is a transmissive diffraction grating.

10. The optical wavelength routing device according to claim 1 where the optical beam-splitting element comprises a flat mirror surface and a beamsplitting region with stepwise segmented width variation in an axis perpendicular to grooves of the diffraction grating to perform spectrally selective routing.

11. The optical wavelength routing device according to claim 10 where the stepwise segmented regions have a smoothed transition between them.

12. The optical wavelength routing device according to claim 1 where the optical beam-splitting element comprises a flat mirror surface and at least two separate beamsplitting regions of optical reflection and/or transmission along an axis that is perpendicular to grooves in the diffraction grating to perform spectrally selective signal routing.

13. The optical wavelength routing device according to claim 1 where the optical beam-splitting element comprises a flat mirror with spatially varying reflectivity to perform spectrally selective routing and to impart a desired wavelength dependent loss.

14. The optical wavelength routing device according to claim 1 where the optical beam splitting element with spatially varying optical properties has dithered optical transition regions to reduce PDL of split optical beams.