150results about How to "Low bending loss" patented technology

A radiation resistant single-mode optical fiber has a core and a cladding, each made of fluorine-doped silica glass, in which a chlorine concentration of the core is at least 0.01 ppm, a relative refractive index difference of the core based on the refractive index for silica is between −0.30 and −0.10%, a relative refractive index difference of the core based on the refractive index for the cladding is between 0.3% and 0.5%, a cutoff wavelength is 1.27 μm or below, and a bending loss at a wavelength of 1.3 μm and a bending diameter of 20 mm is 0.5 dB/m or less.

An optical fiber with improved bending behavior is disclosed. The optical fiber, a single mode optical fiber having core and clad, satisfies alpha-profile wherein a refractive index in the core is increased toward its center, and has a specific refractive index difference Delta1 in the central region of the core and Delta2 at a radius rcore of the core. The optical fiber also satisfies a mode field diameter of 8.6~9.5 m at 1310nm wavelength, a zero dispersion wavelength of 1300~1324nm, a dispersion of 18 ps/nm-km or less at a 1550nm, a cable cutoff wavelength of 1260nm or less, a bending loss of 0.1dB or less at 1625nm when wound 100 times with a bending radius of 25mm. Thus, the optical fiber may satisfy every optical characteristic such as zero dispersion wavelength and dispersion at 1500nm, suggested by the general and common signal mode optical fiber, though the bending loss is decreased.

The invention discloses a bending insensitive single mode fiber. The fiber comprises a fiber core, inner cladding, subsidence cladding and outer cladding. The refractive index of the fiber core is n1, the refractive index of the inner cladding is n2, the refractive index of the subsidence cladding is n4, the subsidence cladding of the outer cladding is n3, the refractive index n1 remains unchanged along with increasing of the radius of the fiber core, the refractive index n2 remains unchanged along with increasing of the radius of the inner cladding, the refractive index n4 of the subsidence cladding is increased along with increasing of the radius until the refractive index n4 of the subsidence cladding is the same as the refractive index n3 of the outer cladding, n1>n2>n3>n4, n4 is increased along with increasing of the radius, no obvious refraction face exists, the refractive index of the interface is progressively increased from interior to exterior, and therefore optical loss due to the fact that a light intensity tail field is exposed out of the refraction face is avoided. Therefore, compared with a traditional similar optical fiber, the bending insensitive single mode fiber has the better bending resistance performance and the smaller bending loss and has the better compatibility with the G.652D.

The invention relates to a single-mode optical fiber and an optical system, the single-mode optical fiber comprises a central core, an intermediate cladding, a trench, and optical cladding. The central core has a refractive index difference n 1 relative to the optical cladding in the range 2.610 -3 to 3.510 -3 . The trench has a radius r 3 that is less than 24 [mu]m. The refractive index difference n 3 of the trench relative to the optical cladding is in the range -15.010 -3 to -4.510 -3 at 633 nm. The volume V 13 of the trench, defined as follows: V 13 is in the range 170 %.[mu]m 2 to 830 %.[mu]m 2 . This fiber has an effective area greater than or equal to 150 [mu]m 2 at a wavelength of 1550 nm and lower bending losses. Use in particular in long-haul terrestrial systems or undersea systems with or without repeaters.

The invention discloses an electrically controlled micronano optical fiber optical switch based on a graphene thin film. The electrically controlled micronano optical fiber optical switch comprises a tapering light output micronano optical fiber, a tapering light input micronano optical fiber and a circuit control module based on the graphene thin film, wherein in the circuit control module based on the graphene thin film, a silicon base coated with the graphene thin film is used as a center; a metal electrode is arranged on the rim of the silicon base; the tapering light output micronano optical fiber and the tapering light input micronano optical fiber are oppositely arranged on the graphene silicon base; the ends of the two micronano optical fibers are adsorbed together by a van der Waals force, and serve as a coupling end of a light path; and ultraviolet photoresist with low refractive index is coated on the micronano optical fibers. On the basis of the property of graphene, the novel optical fiber optical switch has the characteristics of small size, short response time, low driving voltage and improved reliability by combining the evanescent wave characteristics of the micronano optical fibers.

The invention belongs to the photoelectronic technical field, and discloses an M-Z electrooptical modulator provided with tunable gratings and based on graphene-molybdenum disulfide heterojunctions. The M-Z electrooptical modulator comprises a substrate layer, the in-out tunable gratings, in-out straight-light waveguides, S-type bent Y-branch waveguides and a two-arm straight light waveguide, wherein the in-out tunable gratings, the in-out straight-light waveguides, the S-type bent Y-branch waveguides and the two-arm straight light waveguide are fully embedded in the substrate layer and successively connected with each other, and the two-arm straight light waveguide is successively provided with a second graphene layer, molybdenum disulfide and a first graphene layer from the bottom up; the second graphene layer is connected to a second electrode mounted between the two arms, and each in-out tunable grating is successively provided with a fourth graphene layer, a boron nitride isolation layer and a third graphene layer while the third and the fourth graphene layers are connected to the a fourth electrode and a fifth electrode respectively. Compared with the prior art, the M-Z electrooptical modulator has the advantages of being small in size, easy to integrate, deep in modulation, high in extinction ratio, big in temperature tolerance and the like.

The invention provides a gas detection system based on a hollow-core anti-resonance optical fiber. The gas detection system comprises a laser device, a first gas cavity, a hollow-core anti-resonance optical fiber, a second gas cavity, a spectrograph and a data processing device, wherein two ends of the hollow-core anti-resonance optical fiber are respectively communicated with the first gas cavityand the second gas cavity; the first gas cavity and the second gas cavity are used for injecting to-be-detected gas into the hollow-core anti-resonance optical fiber; the laser device is used for inputting detection laser into the hollow-core anti-resonance optical fiber; the spectrograph is used for measuring Raman scattering light generated by to-be-detected gas; and the data processing deviceis used for processing a Raman spectrum and analyzing the contents and concentration of to-be-detected gas. The hollow-core anti-resonance optical fiber has the characteristics that the transmission loss is low, the transmission bandwidth is wide, the bending loss is low, the damage threshold is high, and single mode transmission is maintained; and the Raman scattering threshold is reduced, and the contents and the concentration of trace gas can be detected by virtue of pump light with relatively low power.

The invention relates to a terahertz low-loss bent waveguide which comprises an outer waveguide plate and an inner waveguide plate. The outer waveguide plate and the inner waveguide plate are bent metal plates and bent portions of the plates are arc. The outer waveguide plate is parallel to the inner waveguide plate with a distance in between. Periodical grooves are formed in opposite surfaces of the outer waveguide plate and the inner waveguide plate. Terahertz waves are input from one end of the outer waveguide plate and one end of the inner waveguide plate in a horizontal magnetic wave mode and enter a gap between the outer waveguide plate and the inner waveguide plate so that surface waves can be transmitted in the gap, and are further transmitted to the other end of the outer waveguide plate and the outer end of the inner waveguide plate. Thus, low-loss bent transmission of the terahertz waves is achieved. According to the technical scheme, the bent loss of the terahertz waves is low and the terahertz low-loss bent waveguide is simple in structure, convenient to use and low in cost.

The invention relates to a single mode fiber and a manufacturing method thereof. The single mode fiber comprises a core layer and a covering layer. The single mode fiber is characterized in that the diameter a of the core layer is 9.9-10.9 micrometers, and the delta 1 is 2.1*10<-3>-3.8*10<-3>; the covering layer outside the core layer sequentially comprises an inner covering layer, a sunk covering layer and an outer covering layer from inside to outside; the diameter b of the inner covering layer is 16-22 micrometers, and the delta 2 is -5*10<-4>-5*10<-4>; the diameter c of the sunk covering layer is 24-38 micrometers, and the delta 3 is -15*10<-3>--3*10<-3>, and the width of the sunk covering layer is 4-11 micrometers. According to the single mode fiber, the effective area of the fiber is equal to or larger than 110 micrometer <2>, and the nonlinear effect in the transmission fiber is lowered effectively. In addition, the comprehensive performance parameters of the cutoff wavelength, the bending loss, the chromatic dispersion and the like are good in the application wave band, so that the single mode state of optical signals of the fiber in transmission and application of the C wave band is guaranteed. The size of the core layer of the fiber is controlled reasonably, so that the manufacturing cost of the fiber is lowered effectively, and good balance between the manufacturing cost of the fiber and the performance parameters of the fiber is achieved.

Disclosed herein is a flexible film optical waveguide, which is in flexible film form and includes upper and lower cladding layers, each of which is formed of an organic-inorganic hybrid material, and a core layer provided between the upper and lower cladding layers and formed of an organic-inorganic hybrid material having a refractive index higher than that of the organic-inorganic hybrid material of each of the upper and lower cladding layers. In addition, a method of fabricating such a flexible film optical waveguide is also provided.

The invention relates to a gain photon crystal optical fiber waveguide, which is composed of a core layer and a coating layer which surrounds the core layer. The inner coating layer of the optical fiber comprise solid microstructure point lattice which is formed by germanium-doped silica column, and forms outer bandgap of the gain optical fiber, the function thereof is that the multimode pump light can be strictly restricted in a second fiber core region which is provided with rare earth dopant ion, and improves the utilizing efficiency of the pump light; the second fiber core of the optical fiber is composed of the solid microstructure point lattice which is formed the rare earth ion silica column to form the inner bandgap of the gain optical fiber, the function thereof is that through the multimode pump light, the generated laser light can be strictly restricted in a first fiber core region which is formed by high pure silica glass. Adopting the solid gain photon crystal optical fiber can greatly improve the utilization efficiency of the pump light, improve beam quality of output laser light, enhance output power of the optical fiber laser, and reduce nonlinear effect of the high-power laser device.

The invention discloses a tortuous two-way surface wave splitter, which comprises two metal grating structures (1) and metal wires, wherein each metal grating structure (1) is adjustable in thickness and tortuosity; the metal wires are arranged at one end of each of the two metal grating structures (1); the surfaces of the two metal grating structures (1) are provided with grooves (12) with different structural parameters respectively; and the structural parameters comprise a depth, a width, a cycle and a cross section shape. In the tortuous two-way surface wave splitter, artificial surface plasmas on the metal grating structures (2) of which the surfaces are provided with the grooves (12) are excited by the metal wires. The tortuous two-way surface wave splitter realizes the functions of the two-way surface wave splitter with relatively lower bending loss for the first time, and is simple, effective, convenient to machine and wide in application range.

The invention discloses a bending-insensitive single mode fiber and a manufacturing method of the bending-insensitive single mode fiber. The bending-insensitive single mode fiber comprises a fiber core and wrapping layers, wherein the wrapping layers outside the fiber core sequentially include the inner wrapping layer, the fluorine-doped refractive index lowering wrapping layer and the outer wrapping layer from inside to outside. The manufacturing method of the bending-insensitive single mode fiber includes the following steps of firstly, manufacturing a mandrel according to a VAD method; secondly, manufacturing the fluorine-doped refractive index lowering wrapping layer according to an OVD method; thirdly, depositing the outer wrapping layer outside the fluorine-doped refractive index lowering wrapping layer to obtain a fluorine-doped wrapped pipe; fourthly, inserting the mandrel into the fluorine-doped wrapped pipe, and sintering the mandrel and the fluorine-doped wrapped pipe into a whole; fifthly, conducting optical fiber wire drawing so that the manufactured optical fiber stick can be drawn to form an optical fiber. Compared with a traditional similar optical fiber, the bending-insensitive single mode fiber has better bending prevention performance and smaller bending loss and can be better compatible with G.652D, and the manufacturing method is simple.

The invention discloses an optical waveguide chip with a micro-optical gyroscope Sagnac effect and a preparation method thereof. The optical waveguide chip comprises a substrate, an SiO2 (Silicon Dioxide) lower cladding layer and an SiO2 core area light guide, wherein the SiO2 core area light guide comprises an input straight waveguide part, two arc-shaped bend waveguide parts, an Achimedean spiral bending waveguide part and an output straight waveguide part; an input straight waveguide part of the SiO2 lower cladding layer and a spiral ring of the Achimedean spiral bending waveguide part are vertically crossed, so as to reduce the loss of an X Achimedean spiral bending waveguide part; two arc bending waveguide parts are oppositely connected, an input direct waveguide terminal and a starting end of the Achimedean spiral bending waveguide part are smoothly connected, and an optimal dislocation offset can be guided on the end plane of a wave guide connecting place, so that the bending loss is less. According to the optical waveguide chip, the sensitivity of the gyroscope can be improved, and the noise of the gyroscope can be reduced.

The invention relates to a flexible ultra-long surface plasmon polariton waveguide which comprises a photoelectric input end, a photoelectric output end, a flexible substrate and a flexible surface plasmon polariton waveguide line array, wherein the flexible surface plasmon polariton waveguide is manufactured on the flexible waveguide substrate, then a planar waveguide structure is bent, edges are further aligned for welding, and an ultra-long surface plasmon polariton waveguide structure with the independent photoelectric input end and the photoelectric output end is finally formed. The flexible surface plasmon polariton waveguide array comprises a flexible organic polymer cladding layer and a waveguide metal core layer, a selected metal material is gold, silver, copper, aluminum and other precious metal materials with surface plasmon resonance property in a light frequency wave band, and all light waveguide structures are made of an organic flexible polymer material, so that the flexible ultra-long surface plasmon polariton waveguide has great flexibility, can be bent arbitrarily and even folded, is small in volume and can further improve portability; and the surface plasmon polariton waveguide capable of simultaneously conducting photoelectric signals is adopted as a core layer, so that the obstacle that the photoelectric signals are not compatible is broken.