Tunable chromatic dispersion, dispersion slope, and polarization mode dispersion compensator utilizing a virtually imaged phased array

A method for dispersion compensation for a composite optical signal in an optical fiber transmission system, the composite optical signal comprising a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprises unwanted chromatic dispersion, dispersion slope, and polarization mode dispersion (PMD), comprising the steps of:

• (a) propagating the composite optical signal in a forward direction;
• (b) separating the wavelengths in the band of wavelengths in each of the plurality of channels, wherein each of the wavelengths in the band is spatially distinguishable from the other wavelengths in the band;
• (c) spatially separating each band of wavelengths in the plurality of channels, wherein the spatially separating step (c) further comprises:
• (c1) compressing the spatially separated bands of wavelengths along a single dimension;
• (d) spatially separating each wavelength of each separated band of wavelengths into a plurality of polarized rays;
• and
• (e) reflecting the plurality of polarized rays toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A method for dispersion compensation for a composite optical signal in an optical fiber transmission system, the composite optical signal comprising a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprises unwanted chromatic dispersion, dispersion slope, and polarization mode dispersion (PMD), comprising the steps of:

• (a) propagating the composite optical signal in a forward direction;
• (b) separating the wavelengths in the band of wavelengths in each of the plurality of channels, wherein each of the wavelengths in the band is spatially distinguishable from the other wavelengths in the band;
• (c) spatially separating each band of wavelengths in the plurality of channels;
• (d) spatially separating each wavelength of each separated band of wavelengths into a plurality of polarized rays;
• and
• (e) reflecting the plurality of polarized rays toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated, wherein in the reflecting step (e), each of the plurality of polarized rays intercepts at least one mirror at a different position, wherein a first polarized ray intercepts a first mirror and a second polarized ray intercepts a second mirror.

A dispersion compensator, comprising:

• a Virtually Imaged Phased Array (VIPA) optically coupled to an optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• at least one diffraction grating, wherein a first side of the at least one diffraction grating is optically coupled to a second side of the VIPA;
• at least one birefringent wedge, wherein a first side of the at least one birefringent wedge is optically coupled to a second side of the at least one diffraction grating;
• at least one focusing lens, wherein a first side of the at least one focusing lens is optically coupled to a second side of the at least one birefringent wedge;
• and
• at least one mirror optically coupled to a second side of the at least one focusing lens, wherein the at least one mirror reflects a plurality of polarized rays of each of spatially separated bands of wavelengths toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A dispersion compensator, comprising:

• a Virtually Imaged Phased Array (VIPA) optically coupled to an optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• at least one diffraction grating, wherein a first side of the at least one diffraction grating is optically coupled to a second side of the VIPA;
• at least one birefringent wedge, wherein a first side of the at least one birefringent wedge is optically coupled to a second side of the at least one diffraction grating;
• at least one focusing lens, wherein a first side of the at least one focusing lens is optically coupled to a second side of the at least one birefringent wedge;
• and
• at least one mirror optically coupled to a second side of the at least one focusing lens, wherein the at least one mirror reflects a plurality of polarized rays of each of spatially separated bands of wavelengths toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated, wherein the at least one mirror comprises:
• a first mirror optically coupled to the second side of the at least one focusing lens, and
• a second mirror optically coupled to the second side of the at least one focusing lens.

A dispersion compensator, comprising:

• a VIPA optically coupled to an optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• a diffraction grating, wherein a first side of the diffraction grating is optically coupled to a second side of the VIPA;
• a first birefingent wedge, wherein a first side of the first birefringent wedge is optically coupled to a second side of the diffraction grating;
• a second birefringent wedge, wherein a first side of the second birefringent wedge is optically coupled to a second side of the first birefringent wedge;
• a first focusing lens, wherein a first side of the first focusing lens is optically coupled to a second side of the second birefringent wedge;
• a second focusing lens, wherein a first side of the second focusing lens is optically coupled to the second side of the second birefringent wedge;
• a first mirror optically coupled to a second side of the first focusing lens, wherein the first mirror reflects a first polarized ray of each wavelength of each spatially separated band of wavelengths toward a return direction;
• and
• a second mirror optically coupled to a second side of the second focusing lens, wherein the second mirror reflects a second polarized ray of each wavelength of each spatially separated band of wavelengths toward a return direction, wherein a polarization plane orientation of the first and second polarized rays are mutually orthogonal, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A dispersion compensator, comprising:

• a VIPA optically coupled to an optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• a first diffraction grating, wherein a first side of the first diffraction grating is optically coupled to a second side of the VIPA;
• a second diffraction grating, wherein a first side of the second diffraction grating is optically coupled to a second side of the first diffraction grating;
• a birefringent wedge, wherein a first side of the birefringent wedge is optically coupled to a second side of the second diffraction grating;
• a focusing lens, wherein a first side of the focusing lens is optically coupled to a second side of the birefringent wedge;
• a first mirror optically coupled to a second side of the focusing lens, wherein the first mirror reflects a first polarized ray of each wavelength of each spatially separated band of wavelengths toward a return direction;
• and
• a second mirror optically coupled to the second side of the focusing lens, wherein the second mirror reflects a second polarized ray of each wavelength of each spatially separated band of wavelengths toward a return direction, wherein a polarization plane orientation of the first and second polarized rays are mutually orthogonal, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A dispersion compensator, comprising:

• a VIPA optically coupled to an optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• a first diffraction grating, wherein a first side of the first diffraction grating is optically coupled to a second side of the VIPA;
• a second diffraction grating, wherein a first side of the second diffraction grating is optically coupled to a second side of the first diffraction grating;
• a first birefringent wedge, wherein a first side of the first birefringent wedge is optically coupled to a second side of the second diffraction grating;
• a second birefringent wedge, wherein a first side of the second birefringent wedge is optically coupled to a second side of the first birefringent wedge;
• a first focusing lens, wherein a first side of the first focusing lens is optically coupled to a second side of the second birefringent wedge;
• a second focusing lens, wherein a first side of the second focusing lens is optically coupled to the second side of the second birefringent wedge;
• a first mirror optically coupled to a second side of the first focusing lens, wherein the first mirror reflects a first polarized ray of each wavelength of each spatially separated band of wavelengths toward a return direction;
• and
• a second mirror optically coupled to a second side of the second focusing lens, wherein the second mirror reflects a second polarized ray of each wavelength of each spatially separated band of wavelengths toward a return direction, wherein a polarization plane orientation of the first and second polarized rays are mutually orthogonal, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A system, comprising:

• an optical fiber transmission system;
• and
• a dispersion compensator optically coupled to the optical fiber transmission system, the dispersion compensator comprising:
• a VIPA optically coupled to the optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• at least one diffraction grating, wherein a first side of the at least one diffraction grating is optically coupled to a second side of the VIPA;
• at least one birefringent wedge, wherein a first side of the at least one birefringent wedge is optically coupled to a second side of the at least one diffraction grating;
• at least one focusing lens, wherein a first side of the at least one focusing lens is optically coupled to a second side of the at least one birefringent wedge;
• and
• at least one mirror optically coupled to a second side of the at least one focusing lens, wherein the at least one mirror reflects a plurality of polarized rays of each of spatially separated bands of wavelengths toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A system, comprising:

• an optical fiber transmission system;
• and
• a dispersion compensator optically coupled to the optical fiber transmission system, the dispersion compensator comprising:
• a VIPA optically coupled to the optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• at least one diffraction grating, wherein a first side of the at least one diffraction grating is optically coupled to a second side of the VIPA;
• at least one birefringent wedge, wherein a first side of the at least one birefringent wedge is optically coupled to a second side of the at least one diffraction grating;
• at least one focusing lens, wherein a first side of the at least one focusing lens is optically coupled to a second side of the at least one birefringent wedge;
• and
• at least one mirror optically coupled to a second side of the at least one focusing lens, wherein the at least one mirror reflects a plurality of polarized rays of each of spatially separated bands of wavelengths toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated, wherein the at least one mirror comprises:
• a first mirror optically coupled to the second side of the at least one focusing lens, and
• a second mirror optically coupled to the second side of the at least one focusing lens.

A system comprising:

• an optical fiber transmission system;
• an optical circulator, wherein a first port and a third port of the optical circulator are optically coupled to the optical fiber transmission system;
• and
• a dispersion compensator optically coupled to a second port of the optical circulator, the dispersion compensator comprising:
• a VIPA optically coupled to the optical fiber transmission system at a first side, wherein a composite optical signal from the optical fiber transmission system is capable of traversing through the VIPA in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the bands of wavelengths comprise unwanted chromatic dispersion, dispersion slope, and PMD;
• at least one diffraction grating, wherein a first side of the at least one diffraction grating is optically coupled to a second side of the VIPA;
• at least one birefringent wedge, wherein a first side of the at least one birefringent wedge is optically coupled to a second side of the at least one diffraction grating;
• at least one focusing lens, wherein a first side of the at least one focusing lens is optically coupled to a second side of the at least one birefringent wedge;
• and
• at least one mirror optically coupled to a second side of the at least one focusing lens, wherein the at least one mirror reflects a plurality of polarized rays of each of spatially separated bands of wavelengths toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A system, comprising:

• a dispersion compensator;
• and
• a composite optical signal traversing through the dispersion compensator, wherein the composite signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the band of wavelengths comprises unwanted chromatic dispersion, dispersion slope and PMD,
• wherein the composite optical signal is propagated in a forward direction,
• wherein the wavelengths in the band of wavelengths in each of the plurality of channels are separated, wherein each of the wavelengths in the band is spatially distinguishable from the other wavelengths in the band,
• wherein each band of wavelengths in the plurality of channels is spatially separated,
• wherein each wavelength of each separated band of wavelengths is spatially separated into a plurality of polarized rays, and
• wherein the plurality of polarized rays is reflected toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.

A system, comprising:

• means for propagating a composite optical signal in a forward direction, wherein the composite optical signal comprises a plurality of channels, each of the plurality of channels comprising a band of wavelengths, wherein the band of wavelengths comprises unwanted chromatic dispersion, dispersion slope and PMD;
• means for separating the wavelengths in the band of wavelengths in each of the plurality of channels, wherein each of the wavelengths in the band is spatially distinguishable from the other wavelengths in the band;
• means for spatially separating each band of wavelengths in the plurality of channels;
• means for spatially separating each wavelength of each separated band of wavelengths into a plurality of polarized rays;
• and
• means for reflecting the plurality of polarized rays toward a return direction, wherein dispersion is added to the reflected plurality of polarized rays such that the unwanted chromatic dispersion, dispersion slope, and PMD are compensated.