Integrated pump combining module

A method of combining optical beams comprising:

• providing a first beam angle turner which includes a first birefringent wedge with a first optic axis oriented in a first direction and a second birefringent wedge with a second optic axis oriented in a second direction different from the first direction;
• providing a second beam angle turner which includes a third birefringent wedge with a third optic axis oriented in a third direction, a fourth birefringent wedge with a fourth optic axis oriented in a fourth direction different from the third direction, and a Faraday rotator disposed between the third and fourth wedges;
• providing a wavelength division multiplexer (WDM) that is disposed between the first and second beam angle turners and that transmits light of a first wavelength and that reflects light of a second wavelength, said WDM having a first surface facing the second wedge opposite the first wedge and a second surface facing the fourth wedge opposite the Faraday rotator;
• receiving and combining in the first beam angle turner first and second linearly polarized optical beams having the first wavelength and mutually orthogonal polarizations to form a first polarization combined beam;
• receiving, polarization rotating, and combining in the second beam angle turner third and fourth linearly polarized optical beams having the second wavelength and mutually orthogonal polarizations to form a second polarization combined beam;
• transmitting the first and second optical beams through the WDM and reflecting the third and fourth optical beams from the second surface of the WDM;
• and
• combining the first and second polarization combined beams into an exit beam, said exit beam propagating along an exit beam path through the second beam angle turner;
• and
• whereby reflected light reflected back along the exit beam path is isolated from the first, second, third, and fourth optical beams.

A device for combining optical beams comprising:

• a beam angle turner which includes a first birefringent wedge with a first optic axis oriented in a first direction and a second birefringent wedge with a second optic axis oriented in a second direction different from the first direction;
• a wavelength division multiplexer (WDM) that transmits light of a first wavelength and that reflects light of a second wavelength, the WDM having a first surface facing the first wedge opposite the second wedge;
• first and second polarization maintaining (PM) fiber terminations facing a second surface of the WDM opposite the first surface;
• a first collimating lens disposed between the second surface of the WDM and the first and second PM fiber terminations;
• third and fourth PM fiber terminations facing the second wedge opposite the first wedge;
• an exit beam optical fiber termination disposed between the third and fourth PM fiber terminations and facing the second wedge opposite the first wedge;
• and
• a second collimating lens disposed between the second wedge and the third and fourth PM fiber terminations and the exit beam optical fiber termination;
• wherein the first direction forms an angle of 90° with the second direction;
• and
• wherein the beam angle turner, WDM, first and second collimating lenses, first, second, third, and fourth PM fiber terminations, and the exit beam optical fiber termination are integrated into a single module.

A method of combining optical beams comprising:

• providing a beam angle turner which includes a first birefringent wedge with a first optic axis oriented in a first direction and a second birefringent wedge with a second optic axis oriented in a second direction different from the first direction;
• providing a wavelength division multiplexer (WDM) that transmits light of a first wavelength and that reflects light of a second wavelength, the WDM having a first surface facing the first wedge opposite the second wedge;
• providing first and second polarization maintaining (PM) fiber terminations facing a second surface of the WDM opposite the first surface;
• providing a first collimating lens disposed between the second surface of the WDM and the first and second PM fiber terminations;
• providing third and fourth PM fiber terminations facing the second wedge opposite the first wedge;
• providing an exit beam optical fiber termination disposed between the third and fourth PM fiber terminations and facing the second wedge opposite the first wedge;
• providing a second collimating lens disposed between the second wedge and the third and fourth PM fiber terminations and the exit beam optical fiber termination;
• launching first and second linearly polarized optical beams having the first wavelength and mutually orthogonal polarizations from the first and second PM fiber terminations, respectively, through the first collimating lens toward the second surface of the WDM with a first separation angle Θ at incidence upon the second surface;
• transmitting the first and second optical beams through the WDM;
• launching third and fourth linearly polarized optical beams having the second wavelength and mutually orthogonal polarizations from the third and fourth PM fiber terminations, respectively, through the second collimating lens toward the second wedge with a separation angle 2Θ at incidence upon the second wedge;
• deflecting the third and fourth optical beams in the beam angle turner such that the third and fourth optical beams are incident upon the first surface of the WDM with a second separation angle Θ at incidence;
• reflecting the third and fourth optical beams from the first surface;
• combining the transmitted first and second optical beams and the reflected third and fourth optical beams to form a polarization combined exit beam, said exit beam propagating along an exit beam path through the beam angle turner;
• and
• receiving the exit beam at the exit beam optical fiber termination;
• wherein the first direction forms an angle of 90° with the second direction;
• and
• wherein the beam angle turner, WDM, first and second collimating lenses, first, second, third, and fourth PM fiber terminations, and the exit beam optical fiber termination are integrated into a single module.

A device for combining optical beams comprising:

• a first beam angle turner which includes a first birefringent wedge with a first optic axis oriented in a first direction, a second birefringent wedge with a second optic axis oriented in a second direction different from the first direction, and a first Faraday rotator disposed between the first and second wedges;
• a second beam angle turner which includes a third birefringent wedge with a third optic axis oriented in a third direction, a fourth birefringent wedge with a fourth optic axis oriented in a fourth direction different from the third direction, and a second Faraday rotator disposed between the third and fourth wedges;
• and
• a wavelength division multiplexer (WDM) that is disposed between the first and second beam angle turners and that transmits light of a first wavelength and that reflects light of a second wavelength, said WDM having a first surface facing the second wedge opposite the first Faraday rotator and a second surface facing the fourth wedge opposite the second Faraday rotator.

A method of combining optical beams comprising:

• providing a first beam angle turner which includes a first birefringent wedge with a first optic axis oriented in a first direction, a second birefringent wedge with a second optic axis oriented in a second direction different from the first direction, and a first Faraday rotator disposed between the first and second wedges;
• providing a second beam angle turner which includes a third birefringent wedge with a third optic axis oriented in a third direction, a fourth birefringent wedge with a fourth optic axis oriented in a fourth direction different from the third direction, and a second Faraday rotator disposed between the third and fourth wedges;
• providing a wavelength division multiplexer (WDM) that is disposed between the first and second beam angle turners and that transmits light of a first wavelength and that reflects light of a second wavelength, said WDM having a first surface facing the second wedge opposite the first Faraday rotator and a second surface facing the fourth wedge opposite the second Faraday rotator;
• receiving, polarization rotating, and combining in the first beam angle turner first and second linearly polarized optical beams having the first wavelength and mutually orthogonal polarizations to form a first polarization combined beam;
• receiving, polarization rotating, and combining in the second beam angle turner third and fourth linearly polarized optical beams having the second wavelength and mutually orthogonal polarizations to form a second polarization combined beam;
• transmitting the first and second optical beams through the WDM and reflecting the third and fourth optical beams from the second surface of the WDM;
• and
• combining the first and second polarization combined beams into an exit beam, said exit beam propagating along an exit beam path through the second beam angle turner;
• and
• whereby reflected light reflected back along the exit beam path is isolated from the first, second, third, and fourth optical beams.

A device for combining optical beams comprising:

• a first beam angle turner which includes first and second birefringent wedges and a first Faraday rotator disposed between the first and second wedges;
• a second beam angle turner which includes third and fourth birefringent wedges and a second Faraday rotator disposed between the third and fourth wedges;
• a wavelength division multiplexer (WDM) that is disposed between the first and second beam angle turners and that transmits light of a first wavelength and that reflects light of a second wavelength;
• wherein the first and second wedges and the first Faraday rotator are disposed in relation to each other and contoured such that first and second optical beams of the first wavelength incident on the first wedge at a first prescribed separation angle are combined into a first combined exit beam at the first wavelength that exits the second wedge opposite the first Faraday rotator;
• wherein the third and fourth wedges and the second Faraday rotator are disposed in relation to each other and contoured such that third and fourth optical beams of the second wavelength incident on the third wedge at a second prescribed separation angle are combined into a second combined exit beam that exits the fourth wedge opposite the second Faraday rotator;
• wherein the first beam angle turner, the second beam angle turner and the WDM are disposed in relation to each other such that that the first combined exit beam that exits the second wedge passes through the WDM and is incident upon the fourth wedge opposite the second Faraday rotator and such that the second combined exit beam that exits the fourth wedge is reflected by the WDM and is incident upon the fourth wedge opposite the second Faraday rotator;
• wherein the third and fourth wedges, the second Faraday rotator and the WDM are further disposed in relation to each other and contoured such that,
• the first combined exit beam passes through the second beam angle turner and exits the third wedge and follows an exit beam path intersecting the third wedge opposite the second Faraday rotator,
• the second combined exit beam passes back through the second beam angle turner and exits the third wedge opposite the second Faraday rotator and joins the exit beam path,
• light of the first wavelength reflected back along the exit beam path passes through the second beam angle turner and passes through the WDM, and
• light of the second wavelength that is reflected back along the exit beam path passes through the second beam angle turner, is reflected from the WDM and passes again back through the second beam angle turner and exits the third wedge without interfering with either the third or fourth incident beams;
• wherein the first and second wedges, the first Faraday rotator and the WDM are further disposed in relation to each other and are contoured such that the reflected light of the first wavelength, that is reflected back along the exit beam path through the second beam angle turner and the WDM, passes through the first beam angle turner and exits the first wedge without interfering with either the first or second incident beams;
• whereby the first combined exit beam comprising the first and second incident beams of the first wavelength and the second combined exit beam comprising the third and fourth incident beams of the second wavelength are combined into a third combined exit beam that follows the exit beam path and that includes the first and second wavelengths;
• and
• whereby reflected light reflected back along the exit beam path is isolated from the first, second, third and fourth incident beams.

A method for combining optical beams comprising:

• providing a first beam angle turner which includes first and second birefringent wedges and a first Faraday rotator disposed between the first and second wedges;
• providing a second beam angle turner which includes third and fourth birefringent wedges and a second Faraday rotator disposed between the third and fourth wedges;
• providing a wavelength division multiplexer (WDM) that is disposed between the first and second beam angle turners and that transmits light of a first wavelength and that reflects light of a second wavelength;
• receiving and combining into a first combined exit beam first and second optical beams of the first wavelength;
• receiving and combining into a second combined exit beam third and fourth optical beams of the second wavelength;
• transmitting the first combined exit beam and reflecting the second combined exit beam;
• wherein the first and second wedges and the first Faraday rotator are disposed in relation to each other and contoured such that the first and second optical beams incident on the first wedge at a first prescribed separation angle are combined into the first combined exit beam at the first wavelength that exits the second wedge opposite the first Faraday rotator;
• wherein the third and fourth wedges and the second Faraday rotator are disposed in relation to each other and contoured such that the third and fourth optical beams incident on the third wedge at a second prescribed separation angle are combined into the second combined exit beam that exits the fourth wedge opposite the second Faraday rotator;
• wherein the first beam angle turner, the second beam angle turner and the WDM are disposed in relation to each other such that that the first combined exit beam that exits the second wedge passes through the WDM and is incident upon the fourth wedge opposite the second Faraday rotator and such that the second combined exit beam that exits the fourth wedge is reflected by the WDM and is incident upon the fourth wedge opposite the second Faraday rotator;
• wherein the third and fourth wedges, the second Faraday rotator and the WDM are further disposed in relation to each other and contoured such that,
• the first combined exit beam passes through the second beam angle turner and exits the third wedge and follows an exit beam path intersecting the third wedge opposite the second Faraday rotator,
• the second combined exit beam passes back through the second beam angle turner and exits the third wedge opposite the second Faraday rotator and joins the exit beam path,
• light of the first wavelength reflected back along the exit beam path passes through the second beam angle turner and passes through the WDM, and
• light of the second wavelength that is reflected back along the exit beam path passes through the second beam angle turner, is reflected from the WDM and passes again back through the second beam angle turner and exits the third wedge without interfering with either the third or fourth incident beams;
• wherein the first and second wedges, the first Faraday rotator and the WDM are further disposed in relation to each other and are contoured such that the reflected light of the first wavelength, that is reflected back along the exit beam path through the second beam angle turner and the WDM, passes through the first beam angle turner and exits the first wedge without interfering with either the first or second incident beams;
• whereby the first combined exit beam comprising the first and second incident beams of the first wavelength and the second combined exit beam comprising the third and fourth incident beams of the second wavelength are combined into a third combined exit beam that follows the exit beam path and that includes the first and second wavelengths;
• and
• whereby reflected light reflected back along the exit beam path is isolated from the first, second, third and fourth incident beams.