Focal polarization beam displacer
AssigneeCisco Technology, Inc.
InventorRoman Bruck
Life of this patent
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Abstract
Embodiments herein describe a focal polarization displacer with a birefringent crystal disposed within the focal region of a lens. The birefringent crystal separates optical signals into at least two separate signals based on having different polarization states and an optical axis of the birefringent crystal is set so that focal points of the two separate signals are at an output surface of the polarization displacer where the two separate signals are output from the polarization displacer. This output surface can be a surface of the birefringent crystal or a surface of additional layer coupled to the crystal such as a polarization rotator or dielectric layer.
Claims20
A polarization displacer, comprising:
- a focusing lens configured to receive optical signals;
- and
- a birefringent crystal, which is aligned with the focusing lens, configured to receive the optical signals from the focusing lens and separate the optical signals into at least two separate signals based on having different polarization states, wherein the birefringent crystal is disposed within a focal region of the focusing lens, such that the focal region extends at least partially within the birefringent crystal, wherein an optical axis of the birefringent crystal is set so that respective focal points of the at least two separate signals are aligned at an output surface of the birefringent crystal that is configured for direct coupling to an external optical layer, and wherein the at least two separate signals are output from the polarization displacer at the output surface of the birefringent crystal.
A polarization displacer, comprising:
- a focusing lens configured to receive optical signals;
- and
- a birefringent crystal, on which the focusing lens is disposed, configured to separate the optical signals into at least two separate signals based on having different polarization states, wherein the birefringent crystal is disposed within a focal region of the focusing lens, such that the focal region extends at least partially within the birefringent crystal, wherein an optical axis of the birefringent crystal is set so that respective focal points of the at least two separate signals are aligned at an output surface of the birefringent crystal that is configured for direct coupling to an external optical layer, and wherein the at least two separate signals are output from the polarization displacer at the output surface of the birefringent crystal.
A displacer array, comprising:
- a plurality of focusing lenses, wherein at least a first focusing lens of the plurality of focusing lenses is configured to receive optical signals;
- and
- a single birefringent crystal, which is aligned with the plurality of focusing lenses, configured to receive the optical signals from the first focusing lens and to separate the optical signals into at least two separate signals based on having different polarization states, wherein the single birefringent crystal is disposed within focal regions of the plurality of focusing lenses, such that the focal regions extend at least partially within the birefringent crystal, wherein an optical axis of the single birefringent crystal is set so that focal points of the at least two separate signals corresponding to the optical signals are aligned at a same output surface of the single birefringent crystal that is configured for direct coupling to an external optical layer, and wherein the at least two separate signals are output from the displacer array at the same output surface of the single birefringent crystal.
Dependencies are inferred from the claim text.