Fiber optic terminals, tools and methods for adjusting a split ratio of a fiber optic terminal are disclosed. In one embodiment, a tool for adjusting a split ratio of a fiber optic terminal includes an axle for insertion into a port of the fiber optic terminal, and a terminal engagement body disposed about the axle. The terminal engagement body includes a terminal engagement feature for engaging an alignment feature within the fiber optic terminal, wherein the axle is free to rotate with respect to the terminal engagement body, and a set-point indicator. The tool further includes an end piece coupled to the axle, and a plurality of set-point markers, wherein rotation of the end piece causes rotation of the axle and an alignment between one set-point marker of the plurality of set-point markers with the set-point indicator indicates the split ratio of the fiber optic terminal.

A system for positioning an optical preform in a furnace is provided that includes an upper muffle and a downfeed handle assembly with a tube defining a first end and a second end, the second end extending into the upper muffle. A handle is disposed within the tube. A second end of the handle extends into the upper muffle and a seal assembly is positioned around both the tube and the handle. The first end of the handle extends through the seal assembly and a drive assembly is coupled with the downfeed handle.

A tap coupler includes a mode generation unit, a separation unit, and an output unit. The mode generation unit generates, in accordance with a discontinuous portion disposed on a travelling path of signal light that is propagating, a first mode of the signal light and a second mode that is different from the first mode. The separation unit separates, when the first mode and the second mode are input from the mode generation unit, the first mode and the second mode. The output unit outputs branch light in accordance with a transition of the second mode received from the separation unit.

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.

An example waveguide can include a polymer layer having substantially optically transparent material with first and second major surfaces configured such that light containing image information can propagate through the polymer layer being guided therein by reflecting from the first and second major surfaces via total internal reflection. The first surface can include first smaller and second larger surface portions monolithically integrated with the polymer layer and with each other. The first smaller surface portion can include at least a part of an in-coupling optical element configured to couple light incident on the in-coupling optical element into the polymer layer for propagation therethrough by reflection from the second major surface and the second larger surface portion of the first major surface.

An example waveguide can include a polymer layer having substantially optically transparent material with first and second major surfaces configured such that light containing image information can propagate through the polymer layer being guided therein by reflecting from the first and second major surfaces via total internal reflection. The first surface can include first smaller and second larger surface portions monolithically integrated with the polymer layer and with each other. The first smaller surface portion can include at least a part of an in-coupling optical element configured to couple light incident on the in-coupling optical element into the polymer layer for propagation therethrough by reflection from the second major surface and the second larger surface portion of the first major surface.

The invention is related to devices that couple light into and out of concentric multicore fibers (MCFs). One embodiment of the invention is directed to a multiplexing/demultiplexing coupler, formed using at least two diffractive optical elements, so that light from one of the cores of the concentric MCF exits the coupler along a first axis and the light from another of the cores of the MCF exits coupler along another axis displaced form the first axis. In another embodiment, an add/drop filter includes at least one diffractive optical element, and directs light from one core of the concentric MCF to one fiber and light from one or more other cores of the concentric MCF to another fiber. In another embodiment, a mixing coupler transmits light from inner and outer cores of a first concentric MCF respectively to outer and inner cores of a second concentric MCF.

An indexing terminal arrangement includes a terminal housing that receives an input cable; an optical power splitter disposed within the interior of the terminal housing; a first multi-fiber optical adapter coupled to the terminal housing; a first single-fiber optical adapter coupled to the terminal housing; and a pass-through multi-fiber optical adapter coupled to the terminal housing. Split optical signals are provided to the first multi-fiber optical adapter and the first single-fiber optical adapter. Unsplit and indexed optical signals are provided to the pass-through optical adapter.

An optical multiplexing and demultiplexing method of the present disclosure includes arranging, face to face, a polished surface of a coated optical fiber whose side surface is polished to a core or a vicinity of the core and a polished surface of an optical waveguide whose propagation constant varies in a longitudinal direction and whose side surface is polished to a core or a vicinity of the core, and aligning the polished surface of the coated optical fiber and the polished surface of the optical waveguide so that desired branching ratio is obtained from one end of the coated optical fiber to the end, distal to the former end, of the optical waveguide by relatively moving the polished surface of the coated optical fiber and the polished surface of the optical waveguide.

An optical multiplexing and demultiplexing method of the present disclosure includes arranging, face to face, a polished surface of a coated optical fiber whose side surface is polished to a core or a vicinity of the core and a polished surface of an optical waveguide whose propagation constant varies in a longitudinal direction and whose side surface is polished to a core or a vicinity of the core, and aligning the polished surface of the coated optical fiber and the polished surface of the optical waveguide so that desired branching ratio is obtained from one end of the coated optical fiber to the end, distal to the former end, of the optical waveguide by relatively moving the polished surface of the coated optical fiber and the polished surface of the optical waveguide.