Abstract: A photonic lantern couples light from several fibers or fiber cores into one or more fibers or fiber cores. Photonic lanterns are often used to combine several lower-power beams into a single higher-power beam. They can also be used to couple light from multi-core fibers into single-mode, multi-mode, or other multi-core fibers. By modulating the phases of the input beams, the light can be switched from output to output—for example, between output cores of a multi-core output fiber. If desired, the beams can also be amplified using an active fiber in or coupled to the photonic lantern. A first photonic lantern couples signal light and pump light into the core and cladding, respectively, of an active multi-mode or multi-core fiber. And the active multi-mode or multi-core fiber couples amplified signal light into output fiber(s) via a second photonic lantern.

Abstract: A photonic lantern couples light from several fibers or fiber cores into one or more fibers or fiber cores. Photonic lanterns are often used to combine several lower-power beams into a single higher-power beam. They can also be used to couple light from multi-core fibers into single-mode, multi-mode, or other multi-core fibers. By modulating the phases of the input beams, the light can be switched from output to output—for example, between output cores of a multi-core output fiber. If desired, the beams can also be amplified using an active fiber in or coupled to the photonic lantern. A first photonic lantern couples signal light and pump light into the core and cladding, respectively, of an active multi-mode or multi-core fiber. And the active multi-mode or multi-core fiber couples amplified signal light into output fiber(s) via a second photonic lantern.

Abstract: An improved fiber array arrangement is provided that incorporates spacing and/or spacers between active fibers in a winding to reduce maximum active fiber temperature, with the spacing/spacer material distributed to minimize heating at locations of high pump power. Spacer material such as “dark” fibers and/or metal wires of similar diameter as the active fiber may be employed to aid winding/bundling of active fibers. Further, the use of channels, grooves, wall material and combinations thereof aid structural support/guidance for the winding/bundling of active fibers while providing predefined spacing and heat conductivity that reduces the maximum thermal temperature of the active fiber below design thresholds.

Abstract: An improved arrangement for stripping stray light energy that is propagating in the cladding layer of an optical fiber is provided. A cladding light stripper is provided that incorporates removal of at least a portion of the coating material and/or splicing the fiber to a fiber of differing diameter and/or having a bend of constant or decreasing or varying radius to efficiently remove cladding light while distributing heat dissipation in a controlled design across the device with respect to a specific direction of input (cladding) light.

Abstract: A method for aligning non-circular clad fiber whereby the alignment of the cross sectional profiles of non-circular fiber is accurately aligned before splicing. A method is provided to determine the correct rotational orientation of a fiber with non-circular cladding geometry so that the on screen position of the fiber core may be adjusted to present the flat side of the fiber cladding perpendicular to the imaging axis of the sensor. Once the fiber is clamped into the splicing apparatus multiple images at a series of different known rotational angles are captured. The images are processed to locate key fiber structural features. The relationship between the relevant structures is then processed mathematically to calculate a rotational angle that corresponds to a symmetrical positioning of the core as within the cladding image. The fiber is then rotated to the calculated rotational angle and the splice is completed.

Abstract: A method of processing a work material using a laser can include directing a laser beam of optical energy from a laser to a work material; processing the work material with the laser beam of optical energy in accordance with at least one processing parameter to modify the work material, the processing of the work material having associated therewith an optical signature; sensing a characteristic of the optical signature; and varying the at least one processing parameter responsive to the sensing of the characteristic of the optical signature. Other related methods are disclosed, as are laser processing systems, which systems can be used to practice the methods.

Abstract: A method of processing a work material using a laser can include directing a laser beam of optical energy from a laser to a work material; processing the work material with the laser beam of optical energy in accordance with at least one processing parameter to modify the work material, the processing of the work material having associated therewith an optical signature; sensing a characteristic of the optical signature; and varying the at least one processing parameter responsive to the sensing of the characteristic of the optical signature. Other related methods are disclosed, as are laser processing systems, which systems can be used to practice the methods.

Abstract: A WDM fiber optic communication system is operative to transmit WDM signals between multiple nodes. Each node has a booster EDFA, and in-band and out-of-band supervisory channels monitoring the integrity of a link by generating and detecting respective in-band and out-of-band control signals. The booster EDFA receives the multiplexed WDM and IB signals and generates an output signal carried by fibers between the nodes. The booster EDFA switches from an automatic gain control regime upon detecting of at least one of the IB and OB control signals to an automatic power control regime upon loss of both IB and OB control signals. The output signal of the EDFA in the AGC regime has a high power sufficient for transmitting the WDM and IB signals, and has a low power in the APC regime sufficient for transmitting only the IB control signal.

Abstract: A wavelength division multiplexing (WDM) fiber optic communication system is operative to transmit WDM signals between multiple nodes. Each of the nodes has a booster EDFA, and in-band (IB) and out-of-band (OB) supervisory channels operative to monitor the integrity of a transmission link by generating and detecting respective in-band and out-of-band control signals. The booster EDFA is operative to receive the multiplexed WDM and IB signals and generate an output signal carried by a plurality of fiber-optic cables between the nodes. The booster EDFA is operative to switch from an automatic gain control regime upon detecting of at least one of the IB and OB signals to an automatic power control regime upon loss of both IB and OB signals. The output signal of the EDFA in the AGC regime has a high power sufficient for being transmitted the WDM and IB signals, and has a low power in the APC regime sufficient for transmitting only the IB signal between the nodes.