Abstract: A bending-resistant low-crosstalk photonic orbital angular momentum (OAM) optical fiber waveguide. An optical fiber sequentially comprises, from the center to the outside, a first core layer (1), a second core layer (2), a first cladding layer (3), a second cladding layer (4), and a third cladding layer (5), wherein the third cladding layer (5) is the thickest, the first core layer (1) is the second thickest, and the first cladding layer (3) is the thinnest; the refractive index of the first cladding layer (3) is the lowest, the refractive index of the second cladding layer (4) is the second lowest, and the refractive index of the second core layer (2) is the highest. The waveguide structure can effectively regulate the output of different OAM modes, and an effective refractive index difference between modes is greater than 2×10?4, the modes are easy to separate, and multiplexing and demultiplexing are facilitated.

Abstract: A bending-resistant low-crosstalk photonic orbital angular momentum (OAM) optical fiber waveguide. An optical fiber sequentially comprises, from the center to the outside, a first core layer (1), a second core layer (2), a first cladding layer (3), a second cladding layer (4), and a third cladding layer (5), wherein the third cladding layer (5) is the thickest, the first core layer (1) is the second thickest, and the first cladding layer (3) is the thinnest; the refractive index of the first cladding layer (3) is the lowest, the refractive index of the second cladding layer (4) is the second lowest, and the refractive index of the second core layer (2) is the highest. The waveguide structure can effectively regulate the output of different OAM modes, and an effective refractive index difference between modes is greater than 2×10?4, the modes are easy to separate, and multiplexing and demultiplexing are facilitated.

Abstract: The invention discloses a preparation method and device of active microcrystalline fiber, place the prefabricated rod in the drawing furnace for wire drawing, the drawn fiber is induced by magnetic field in uncoated state and combined with laser treatment technology, the laser beam is focused on the fiber and recrystallized after laser treatment to obtain active microcrystalline fiber. Appropriate laser processing power directly affects the silicate glass fiber in the crystal structure, type, degree of crystallinity, grain size, content, and how much residual phase of glass. Induced by external magnetic field, the thermodynamics and dynamics of crystallization process are changed, make the crystal size distribution is better and uniform, reduce the phenomenon of condensation and makes the grain size is smaller.

Abstract: The invention discloses a preparation method and device of active microcrystalline fiber, place the prefabricated rod in the drawing furnace for wire drawing, the drawn fiber is induced by magnetic field in uncoated state and combined with laser treatment technology, the laser beam is focused on the fiber and recrystallized after laser treatment to obtain active microcrystalline fiber. Appropriate laser processing power directly affects the silicate glass fiber in the crystal structure, type, degree of crystallinity, grain size, content, and how much residual phase of glass. Induced by external magnetic field, the thermodynamics and dynamics of crystallization process are changed, make the crystal size distribution is better and uniform, reduce the phenomenon of condensation and makes the grain size is smaller.

Abstract: Provided are an optical coupling device and an optical coupling unit including the optical coupling device. The optical coupling device includes a right-angle reflecting prism (23) and a mobile optical fibre connector (21). A reflecting surface of the right-angle reflecting prism (23) is provided with a curve reflecting surface (24), the curve reflecting surface being used for gathering and reflecting rays propagated by an optical fibre. The mobile optical fibre connector (21) is fixed to the right-angle reflecting prism (23), to make the rays propagated by the optical fibre being incident on the curve reflecting surface (24) of the right-angle reflecting prism (23).