Apparatus for modulating one or both of spectral phase and amplitude of an optical signal

• US 7,321,454 B2
• Filed: 10/07/2005
• Issued: 01/22/2008
• Est. Priority Date: 10/07/2005
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Marom, Dan M., Dorrer, Christophe J.
• Primary Examiner(s): Mack; Ricky
• Assistant Examiner(s): TRA, TUYEN Q
• Application Number:
  US11/245,760
• Publication Number:
  US 20070081223A1
• Time in Patent Office: 837 Days
• Field of Search: 359/220, 359/222, 359/223, 359/238, 359/320, 359/322, 359/290, 359/291, 359/292, 359/279
• US Class Current: 359/238
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: H04B 10/505 using external modulation
• CPC Class Codes: H04B 10/5053 using a parallel, i.e. shunt, combination of modulators

Abstract

The invention includes a method and apparatus for modulating one or both of spectral phase and amplitude of a received optical signal. The apparatus includes a spatial dispersion mechanism for spatially dispersing the received optical signal to enable optical communication of the received optical signal to an array of modulators. The apparatus includes a modulating mechanism having a first modulating component and a second modulating component. A first portion of the spatially dispersed optical signal is incident on the first modulating component and a second portion of the spatially dispersed optical signal is incident on the second modulating portion. The apparatus further includes a controller coupled to the modulating mechanism. The controller is adapted for moving the first and second modulating components in a direction normal to their planes for modulating one or both of phase and amplitude of the received optical signal.

Claims

1. An apparatus for modulating spectral phase and spectral amplitude of a received optical signal, comprising:

a spatial dispersion mechanism for spatially dispersing a received optical signal into a plurality of spatially dispersed signal components;

a modulating mechanism comprising a plurality of modulating component sets, each modulating component set having associated adjacent modulating components operable for adapting relative phases of respective portions of one of the spatially dispersed signal components, the phase-adapted portions of the spatially dispersed signal component being adapted for modulating spectral phase of the spatially dispersed signal component; and

a spatial filtering mechanism adapted for destructively interfering the phase-adapted portions of the spatially dispersed signal component for modulating spectral amplitude of the spatially dispersed signal component.

2. The apparatus of claim 1, further comprising:

a spatial combination mechanism for spatially combining the phase-adapted portions of the spatially dispersed signal component for coupling the phase-adapted portions of the spatially dispersed signal component into the spatial filtering mechanism.

3. The apparatus of claim 1, further comprising:

a controller coupled to the modulating mechanism, the controller adapted for controllably moving the associated adjacent modulating components.

4. The apparatus of claim 3, wherein controllably moving the associated adjacent modulating components comprises:

controllably moving the associated adjacent modulating components for maintaining a constant separation between the associated adjacent modulating components for modulating thereby the phase of the spatially dispersed signal component; and

controllably moving the associated adjacent modulating components for producing a varying separation between the associated adjacent modulating components for modulating thereby the amplitude of the spatially dispersed signal component.

5. The apparatus of claim 4, wherein the controller is adapted for:

determining a plurality of first phase settings for the associated adjacent modulating components;

determining a plurality of second phase settings for the associated adjacent modulating components; and

adjusting the associated adjacent modulating components from the plurality of first phase settings to the respective plurality of second phase settings.

6. The apparatus of claim 5, further comprising:

a modulating component adjustment mechanism coupled to the controller, the modulating component adjustment mechanism comprising a plurality of adjusting components associated with the associated adjacent modulating components;

wherein the adjusting components are adapted for adjusting the associated adjacent modulating components from the plurality of first phase settings to the plurality of second phase settings.

7. The apparatus of claim 1, wherein the modulating mechanism is adapted such that an energy of the plurality of spatially dispersed signal components is distributed substantially equally across each of the plurality of modulating components.

8. The apparatus of claim 1, wherein the modulating components comprise micromirrors, the micromirrors being controllably moveable in a direction normal to respective planes of the micromirrors.

9. An apparatus, comprising:

a spatial dispersion mechanism for spatially dispersing an optical signal into a plurality of frequency components;

an array of optical reflector sets, each optical reflector set having a plurality of adjacent optical reflectors, wherein each optical reflector in each optical reflector set is normally disposed in a substantially co-planar manner with respect to one of the frequency components, and respective portions of the one frequency component are incident on respective adjacent optical reflectors of the optical reflector set, wherein each optical reflector in each optical reflector set is controllably moveable in a direction normal to its plane to adapt thereby a relative phase of each respective portion of the incident frequency component for modulating spectral phase of the incident frequency component; and

a spatial filtering mechanism adapted for destructively interfering the phase-adapted portions of the incident frequency component for modulating the spectral amplitude of the incident frequency component.

10. The apparatus of claim 9, further comprising:

a spatial combination mechanism for spatially combining the phase-adapted portions of the incident frequency component.

11. The apparatus of claim 9, wherein the spatial filtering mechanism comprises a single mode optical fiber.

12. The apparatus of claim 9, further comprising:

a controller coupled to the array of optical reflector sets, the controller adapted for controllably moving the optical reflectors in each optical reflector set.

13. The apparatus of claim 12, wherein the controller is further adapted for:

controllably moving the optical reflectors in each optical reflector set for maintaining a constant separation between the optical reflectors in each optical reflector set for modulating thereby the phase of the incident frequency component; and

controllably moving the optical reflectors in each optical reflector set for producing a varying separation between the optical reflectors in each optical reflector set for modulating thereby the amplitude of the incident frequency component.

14. An apparatus for modulating one or both of spectral phase and spectral amplitude of a received optical signal, comprising:

a spatial dispersion mechanism for spatially dispersing the received optical signal; and

a modulating mechanism comprising a plurality of modulating component arrays having respective pluralities of modulating components, respective portions of the spatially dispersed optical signal being incident on associated ones of the modulating components;

wherein

the associated ones of the modulating components are adjacent in a direction normal to a dispersion direction of the spatially dispersed optical signal; and

the associated ones of the modulating components are operable for adapting respective phases of the incident portions of the spatially dispersed optical signal, the phase-adapted portions of the spatially dispersed optical signal adaptable for modulating one or both of spectral phase and spectral amplitude of the received optical signal.

15. The apparatus of claim 14, further comprising:

a spatial filtering mechanism adapted for destructively interfering the phase-adapted portions of the spatially dispersed optical signal for modulating the spectral amplitude of the received optical signal.

16. The apparatus of claim 15, wherein the spatial filtering mechanism comprises a single mode optical fiber.

17. The apparatus of claim 14, further comprising:

a spatial combination mechanism for spatially combining the phase-adapted portions of the spatially dispersed optical signal for coupling the phase-adapted portions of the spatially dispersed optical signal into a spatial filtering mechanism.

18. The apparatus of claim 14, further comprising:

a controller coupled to the modulating mechanism, the controller adapted for controllably moving the associated ones of the modulating components.

19. The apparatus of claim 18, wherein controllably moving the associated ones of the modulating components comprises:

controllably moving the associated ones of the modulating components for maintaining a constant separation between the associated ones of the modulating components for modulating thereby the phase of the received optical signal; and

controllably moving the associated ones of the modulating components for producing a varying separation between the associated ones of the modulating components for modulating thereby the amplitude of the received optical signal.