113results about "Microstructured optical fibre" patented technology

The invention discloses a multi-core all-solid-state anti-resonance optical fiber and a multi-wavelength optical fiber laser system. The multi-core all-solid-state anti-resonance optical fiber comprises an inner cladding area, at least two fiber core structures arranged in the inner cladding area and an outer cladding area or a coating layer area arranged on the periphery of the inner cladding area. Each fiber core structure comprises a fiber core area and an anti-resonance area, the anti-resonance area is composed of at least one capillary tube group, each capillary tube group comprises a plurality of capillary tubes, and the capillary tubes in each capillary tube group are annularly arranged on the periphery of the fiber core area by taking the fiber core area as the center; the optical fiber matrixes filled in the capillaries in the anti-resonance area are the same, and the refractive index of the anti-resonance area is n3gt; the refractive index n2 of the inner cladding region is equal to the refractive index n1gt of the fiber core region; and the refractive index of the outer cladding region or the coating layer region is n4. The optical fiber provided by the invention is beneficial to high-density integration of a fiber core structure in a multi-core optical fiber, has a large mode field area and a high-order mode rejection ratio, and gives consideration to both high power and high light beam quality.

The invention discloses a hollow-core microstructure optical fiber ribbon and a preparation method thereof. The hollow-core microstructure optical fiber ribbon comprises a plurality of hollow-core microstructure optical fibers which are arranged side by side; the plurality of hollow-core microstructure optical fibers have the same end face structure and are coated with ribbon combining resin for fixing the positions of the hollow-core microstructure optical fibers; the plurality of anti-resonance microstructure units are distributed on the inner side of the glass sleeve; the glass sleeve is externally coated with the coating on the outermost side; the outermost coating is provided with at least one pair of parallel positioning surfaces; and the positioning surfaces of the adjacent hollow-core microstructure optical fibers are mutually registered and spliced, so that the plurality of hollow-core microstructure optical fibers which are arranged side by side are fixed in the ribbon combining resin in the same direction. According to the hollow-core microstructure optical fiber ribbon provided by the invention, the orientation of the hollow-core microstructure optical fiber is positioned through the non-circular optical fiber coating, and the optical fibers are arranged side by side through the parallel positioning surface, so that the end face orientations of all hollow-core structure optical fibers in the optical fiber ribbon are consistent, and therefore, the welding efficiency is improved, and the welding loss is reduced.

The invention discloses a hollow-core microstructure optical fiber with a positioning surface and a manufacturing method of the hollow-core microstructure optical fiber. The optical fiber comprises a sleeve cladding, a plurality of anti-resonance microstructure units and a coating, the outer contour of the cross section of the sleeve cladding is circular; the plurality of anti-resonance microstructure units are distributed on the inner side of the sleeve cladding; the coating is externally coated on the sleeve wrapping layer; the coating is provided with at least one positioning surface, so that the outer contour of the cross section of the hollow-core microstructure optical fiber is non-circular, and the positioning surface is consistent with the relative positions of the plurality of anti-resonance microstructure units in the length direction. According to the hollow-core microstructure optical fiber with the positioning surface, the orientation of the end face of the hollow-core microstructure optical fiber is marked through the coating positioning surface, the perfect and symmetrical circular structure of the end face of the optical fiber is damaged, end face matching of the optical fiber to be welded is achieved through positioning surface matching, and anti-resonance units of the hollow-core microstructure optical fiber are matched and welded rapidly and accurately; the welding efficiency is improved; and the welding loss is reduced.

The invention belongs to the technical field of hollow-core anti-resonance optical fiber polarization filters, and relates to a hollow-core anti-resonance optical fiber polarization filter based on the SPR effect, an optical fiber comprises six cladding tubes, the six cladding tubes are arranged in a circumferential array, and the circumscribed circle parts of the six cladding tubes are fiber cores; a nesting tube is eccentrically arranged in each cladding tube, the nesting tube is internally tangent to the cladding tube, and the tangent point is the farthest distance from the center of the fiber core; one-third arc sections, close to the fiber core, of the inner walls of the two cladding tubes in the y-axis direction are coated with gold films; six cladding tubes of the optical fiber are tangent to the inner wall of the outer supporting tube. The outermost layer is arranged to be a perfect matching layer and connected with the outer supporting pipe. The hollow-core anti-resonance optical fiber polarization filter based on the SPR effect has the advantages of being simple in process, better in filter performance, easy to control structural parameters and the like.

An optical fiber includes multiple optical cores configured in the fiber including a set of primary cores and an auxiliary core. An interferometric measurement system uses measurements from the multiple primary cores to predict a response from the auxiliary core. The predicted auxiliary core response is compared with the actual auxiliary core response to determine if they differ by more than a predetermined amount, in which case the measurements from the multiple primary cores may be deemed unreliable.

The application provides an optical fiber filter and an optical fiber amplifier, which can realize flat amplification of a few-mode optical signal, and can realize controllable adjustment of optical power of each optical signal mode in a plurality of optical signal modes transmitted by a fiber core of the optical fiber filter. The optical fiber filter comprises a fiber core, an inner cladding and an outer cladding, the refractive index of the fiber core, the refractive index of the inner cladding and the refractive index of the outer cladding are sequentially decreased, the fiber core is used for transmitting at least two different first optical signal modes, the inner cladding is used for transmitting at least two different second optical signal modes, and the fiber core is etched with at least one fiber grating; at least part of optical power of a target first optical signal mode is only coupled with a target second optical signal mode at the fiber grating, wherein the target first optical signal mode is one of the at least two first optical signal modes, and the target second optical signal mode is one of the at least two second optical signal modes.

The invention discloses a few-mode hollow-core anti-resonance optical fiber based on a spiral cladding and a preparation method thereof. The optical fiber structure is sequentially divided into a hollow-core fiber core area, a cladding area and an outer sleeve area from inside to outside; the cladding area is formed by arranging a plurality of spiral anti-resonance structure units along the inner boundary of the outer sleeve area in the angular direction, each spiral anti-resonance structure unit is composed of spiral glass walls with the wall thickness of t, and the distance between the spiral glass walls changes along with the spiral generation direction or is kept at a specific constant. The high-order mode above a specific order is suppressed, and the suppression ratio of the high-order mode to the fundamental mode in the hollow-core optical fiber is regulated and controlled by changing the spiral type and structure parameters, so that the purpose of supporting low-loss transmission of a specific number of different-order modes is achieved. The multi-order mode low-loss transmission antenna has the characteristic of supporting multi-order mode low-loss transmission, can change a spiral line type structure and parameters according to different application scenes, is high in expansibility and feasible in preparation, and has a great application prospect in the application fields of communication, sensing, energy transmission and the like.

The invention provides a three-dimensional photonic crystal fiber device based on triple spiral dislocation, which comprises a plurality of primitive cells periodically arrayed along a Z direction, and the primitive cells are of honeycomb lattice structures and are equally divided into three areas in an X-Y plane; wherein the area I comprises a plurality of first structure units which are periodically arrayed in an X-Y plane, and each first structure unit comprises a structure A, a structure B and a structure C which are arranged from bottom to top; similarly, an area II and an area III are formed, and a second structural unit in the area II comprises a structure C, a structure A and a structure B which are arranged from bottom to top; the third structure unit in the region III comprises a structure B, a structure C and a structure A which are arranged from bottom to top; the structure A, the structure B and the structure C are all regular hexagonal structures and have the same side length; a dislocation transmission line used for light wave transmission is arranged in the center of the primitive cell in the Z direction. Neutral state transmission can be realized only by adjusting a device structure and introducing defects without a magnetic field.

The present invention relates to the technical field of optical isolators, and discloses an optical isolator based on a magnetic photonic crystal fiber, comprising: a central waveguide and two coupled waveguides arranged in parallel with the central waveguide and located on both sides of the central waveguide respectively; the central waveguide includes an input waveguide and an output waveguide. When a light beam is incident forward from the input waveguide, the energy is first coupled from the input waveguide into the coupled waveguides on both sides for transmission, and then coupled into the output waveguide for output. When the light beam is incident backward from the output waveguide, the energy is coupled from the output waveguide into the coupled waveguides on both sides for transmission, and is output from the coupled waveguides; the core of the central waveguide and the core of one of the coupled waveguides are made of quartz material, and the core of the other coupled waveguide is composed of quartz material and magnetic material, and an external magnetic field is applied in the direction perpendicular to the light beam propagation direction, so that the light beam has non-reciprocal characteristics when transmitting in the coupled waveguide whose core is composed of quartz material and magnetic material, improving the isolation effect of the optical isolator.

Provided are a reduced-diameter low-loss optical fiber and an optical cable. The reduced-diameter low-loss optical fiber includes a quartz layer, an adhesive layer, a first coating layer, and a second coating layer which are sequentially provided from inside to outside along a radial direction of the reduced-diameter low-loss optical fiber; where the adhesive layer is configured to increase an adhesive force between the first coating layer and the quartz layer; the first coating layer is configured to protect the quartz layer; and the second coating layer includes a second coating layer matrix and a plurality of reinforcing members, a base material of the second coating layer matrix is the same as that of the first coating layer, and the plurality of reinforcing members are distributed in the second coating layer matrix, so as to increase a strength of the reduced-diameter low-loss optical fiber.

The invention relates to the technical field of optical fiber sensing, in particular to an NHCPCF optical fiber seawater salinity sensor containing double microchannels and a preparation method and application of the NHCPCF optical fiber seawater salinity sensor. The sensor comprises a lead-in type single-mode optical fiber, a node-free hollow-core photonic crystal optical fiber and a lead-out type single-mode optical fiber which are sequentially welded; the node-free hollow-core photonic crystal fiber comprises a first cladding and a main air hole, silicon dioxide tubes are uniformly distributed in the main air hole, the tube wall of each silicon dioxide tube is tangent to the inner wall of the main air hole, and the axis of the main air hole is parallel to the axis of each silicon dioxide tube; the seawater salinity is measured by utilizing an anti-resonance reflection waveguide principle of NHCPCF and a specific micro-channel, a traditional processing mode of opening a large-area cavity in a cladding is not adopted, and the micro-channel is adopted, so that the integration can be improved, the breakage of an optical fiber is effectively avoided, and the mechanical strength in a test is enhanced; the sensor has high sensitivity (salinity sensitivity-0.88 nm / per mill) and good repeatability and stability.

A new class of optical fiber, the fabrication of preforms, and a new type of preform that, when drawn, yields an improved speckle-free output optical fiber, are presented. Useful fibers that achieve speckle-free, smooth output with flat-top transmission of light from Gaussian or few-mode sources are produced from the preforms introduced herein. The unique fabrication of these improved preforms is also presented. The preforms, and thus fibers produced with a variety of core dimensions from about 100 μm to over 1000 μm, are based on a structured silica section with a mode-mixing region adjacent to the inner core or, in the case of noncircular cores, within the core. A plasma vapor deposition process is tailored to achieve the structured section with a well-controlled morphology. The structured section is composed of a number of layer pairs, alternating thin down-doped layers with much thicker layers of core material. The ratio of the core layer thickness to the down-doped layer thickness is about 3 to 25. The number of paired layers is typically between about 8 and 30 layer pairs. The effective NA of the structured section depends on the details of the structured silica section and the individual down-doped layers. Both circular and non-circular inner core examples are possible and are discussed herein.

Disclosed are the fabrication of preforms and novel preforms which, after being drawn, produce novel optical fibers, improved speckle-free output fibers. Useful fibers are made from the preforms described herein to provide speckle-free smooth output with flat-top transmission of light from Gaussian or few-mode sources. Also disclosed are the unique fabrication of these improved preforms. The preforms and the resulting fibers having core sizes varying from about 100 μm to over 1000 μm are based on structured silica segments in the mode mixing region adjacent to the inner core, or in the case of non-circular cores, within the core. The plasma vapor deposition process is modified to achieve the structured segments in a well-controlled manner. The structured segments are composed of multiple paired layers in which thin down-doped layers alternate with much thicker layers of core material. The ratio of the thickness of the core layer to the thickness of the down-doped layer is about 3 to 25. The number of paired layers is typically between about 8 and 30 layer pairs. The effective NA of the structured segments depends on the details of the structured silica segments and the individual down-doped layers. Both circular core examples and non-circular core examples are possible and discussed herein.

The application discloses a kind of photocatalytic optical fibers, including optical fiber core, photocatalytic layer, optical fiber cladding and light reflection film;The optical fiber core is hollow structure, and the optical fiber core outer periphery side is surrounded by optical fiber cladding;The interface of the optical fiber cladding and optical fiber core is coated with photocatalytic layer, and the outer surface of the optical fiber cladding away from optical fiber core is coated with light reflection film;The two ends of the optical fiber core are gas input end and light input end respectively, the gas can enter optical fiber core by gas input end, and can contact with photocatalytic layer and occur photocatalytic reduction reaction;The light can enter optical fiber core by light input end, and can be reflected by light reflection film;The optical fiber structure of the application can effectively enhance the utilization efficiency of light energy, increase the contact frequency of reactant and catalyst, thereby improve the reaction rate of photocatalytic reaction, and further improve the conversion efficiency of CO2.

The invention provides a cladding mode efficient filtering method for microstructure optical fibers, and relates to the technical field of optical fibers, and the method comprises the steps: taking two microstructure optical fibers which are different in structure and have a diameter difference value of a fiber core fundamental mode field within a diameter difference value range, and carrying out the non-oblique-angle cutting of the end faces of the two microstructure optical fibers through a cutting knife; and aligning the axial directions of the two sections of cut micro-structure optical fibers, and splicing at the cutting end surface to obtain a spliced micro-structure optical fiber. The method has the beneficial effects that two sections of microstructure optical fibers with different structures but similar fiber core fundamental mode field diameters are selected, oblique-angle-free cutting is carried out, splicing (welding, butt joint or coupler coupling) is carried out at the cutting end face, and it is ensured that splicing points are axially coaxial but cladding waveguide structures have differences. At a continuous connection point, because the cladding microstructures (such as air hole arrangement, number, shape and the like) of the two sections of optical fibers are discontinuous, the continuity of the cladding waveguide is damaged. Therefore, cladding mode energy is efficiently filtered or scattered, and the strength of the cladding mode energy is greatly weakened.

The invention discloses a multi-channel low-crosstalk multi-layer stepped annular optical fiber and a design method thereof, and belongs to the field of optical communication, and the multi-layer stepped annular optical fiber comprises n (n is greater than or equal to 5 and less than or equal to 10) nested annular structure layers which are sequentially the first to nth annular structure layers from inside to outside; the refractive index of the outermost annular structure layer is smaller than or equal to that of silicon dioxide; the refractive indexes of the first to (n-3) th annular structure layers are greater than the refractive index of the outermost annular structure layer; the refractive index of the (n-2) th embedded structure layer is equal to that of the outermost annular structure layer; the refractive index of the (n-1) th annular structure layer is smaller than that of the outermost annular structure layer; the refractive indexes of the adjacent annular structure layers are different; the width range of the first annular structure layer to the (n-1) th annular structure layer is 1-6 [mu] m and is smaller than the width of the outermost annular structure layer. The number of orbital angular momentum modes which can be supported by the optical fiber and are good in effective refractive index separation can be increased, and therefore the optical communication capacity is improved.

The application discloses an azimuth angle marked hollow core optical fiber and a hollow core optical fiber end face detection method. The optical fiber comprises a cladding hollow core sleeve and a plurality of circumferentially uniformly arranged anti-resonant microstructure units arranged and attached to the inner wall of the cladding hollow core sleeve, and a hollow area surrounded by the anti-resonant microstructure units is a core; the azimuth angle of at least one anti-resonant microstructure unit is different from the azimuth angle of at least one other anti-resonant microstructure unit. The azimuth angle marked hollow core optical fiber and the hollow core optical fiber end face detection method provided by the application can quickly identify the anti-resonant microstructure units in the hollow core optical fiber under the premise that the complexity of the optical fiber preparation is not improved and the transmission performance of the optical fiber is almost not affected, and the geometric uniformity of the anti-resonant microstructure units can be conveniently controlled on line.

To extend the life of a supercontinuum light source. The present invention relates to an optical fiber comprising a core made of a core material and a cladding made of a cladding material, the optical fiber being a nonlinear microstructured optical fiber, which can be obtained by a method comprising a step of loading the core material and, optionally, the cladding material, and the lifetime of the optical fiber can be extended in high pulse applications.

The invention relates to an anti-resonant element preform (100) for manufacturing an anti-resonant hollow-core optical fiber (600), comprising, in an axial top view, a circular first circular element (200) having a first circular radius (250) and an arc-shaped first arc element (300) having a first arc radius (350). The invention further relates to a method for producing an anti-resonant element preform, to a preform for producing an anti-resonant hollow-core optical fiber comprising at least one anti-resonant element preform, and to an anti-resonant hollow-core optical fiber. According to the invention, the first circular element (200) and the first arc element (300) are connected to each other at two contact points (400).

The invention discloses a helmet pressure self-adaptive manufacturing method based on a spiral photonic crystal fiber array, and the method comprises the steps: enabling a photonic crystal fiber array to be embedded in a helmet lining, and monitoring the pressure distribution in real time when the helmet is in contact with a head; collecting pressure data, and demodulating phase change by using phase modulation and interference technologies to quantify pressure; converting the collected pressure data into point cloud data in a three-dimensional space, wherein each point comprises position information and a pressure value; combining the generated pressure point cloud data with the head three-dimensional model, and generating a continuous three-dimensional pressure field through a radial basis function interpolation algorithm; aligning the optical fiber pressure point cloud with the head 3D scanning model through an ICP algorithm; based on the generated three-dimensional pressure field, the thickness distribution of the foaming material is calculated in combination with a nonlinear stress-strain curve of the foaming material; the thickness data of the foaming material obtained through calculation is imported into numerical control foaming forming equipment, mold filling parameters are dynamically adjusted, and personalized customization of the helmet is achieved.

The invention provides a device and method for measuring and improving seed light coupling efficiency in a photonic crystal fiber, the device comprises a seed source, a seed light coupling module, a photonic crystal fiber, a pump light coupling module, a measuring module and an adjusting module, and the measuring module comprises a CCD camera and a power meter. The CCD camera is used for acquiring the amplified end face near-field light spot of the output end of the photonic crystal fiber in real time; the power meter is used for measuring the power of laser output by the photonic crystal fiber. The adjusting module determines the fiber core area power and the total power of the end face near-field light spots, calculates the core-to-package ratio, and adjusts the seed optical coupling module to adjust the core-to-package ratio to the maximum, so that the seed optical coupling efficiency in the photonic crystal fiber reaches the maximum. According to the invention, real-time imaging and analysis can be carried out on the light spot output by the optical fiber through the CCD camera, the coupling state is visually presented, and the measurement uncertainty caused by small hole positioning errors and alignment deviation is avoided, so that the effective coupling efficiency of seed light is accurately improved.

The invention discloses a preparation method of an equivalent large-refractive-index-difference mid-infrared gradient optical fiber based on an alternating refractive index structure, which is characterized by comprising the following steps of: designing the thickness of chalcogenide glass with different refractive indexes: forming a first periodic structure by a low-refractive-index material and a high-refractive-index material on the adjacent outer side of the low-refractive-index material from the original point of a fiber core to the outside in sequence; n + 1 periodic structures are designed outwards in sequence, the outward thickness increment of the low-refractive-index material is xi, i = 1, 2, 3... n, and xi-xi-1 is progressively increased according to the linearity and the power exponent; carrying out precision polishing and grinding on the single chalcogenide glass, carrying out ultrasonic cleaning, stacking and extruding to prepare an all-solid-state optical fiber preform; and finally, inserting into a pre-drilled cladding glass tube for assembling, introducing a protective atmosphere, performing thermal extension processing, and drawing to obtain the equivalent large-refractive-index-difference intermediate infrared gradient optical fiber, which has the advantages that the large refractive index difference and the accurate and flexible regulation and control of a refractive index profile curve can be realized.

The application discloses a kind of low-loss organic ice micro-nano optical fiber and preparation method thereof, the preparation method will be placed along the same line two standard silica single-mode optical fibers with interval, the gap between the end of two standard silica single-mode optical fibers close to each other as sample preparation area, the temperature of sample preparation area is controlled near the glass transition temperature of organic liquid, at slightly higher than the glass transition temperature of organic liquid, the organic liquid of sample preparation area is stretched at uniform speed, thereby preparing high-quality one-dimensional organic ice micro-nano optical fiber.The organic ice micro-nano optical fiber prepared by the method of the application has smooth surface, good diameter uniformity, adjustable diameter and uniform length, can realize low-loss waveguide, and has good mechanical properties, provides a new platform for studying the physical and chemical properties of organic small molecules and expanding its application as functionalized material, and has great research and practical value in the fields of physical chemistry, material science, life science and space exploration.

The present invention relates to an anti-resonant element preform (100) for manufacturing an anti-resonant hollow fiber (600). The anti-resonant element preform includes, in an axial top view, a circular first circular element (200) having a first circular radius (250) and an arcuate first arcuate element (300) having a first arc radius (350). Furthermore, the present invention relates to a method for manufacturing an anti-resonant element preform, a preform for manufacturing an anti-resonant hollow fiber including at least one anti-resonant element preform, and an anti-resonant hollow fiber. According to the present invention, it is provided that the first circular element (200) and the first arcuate element (300) are connected to each other at two contact points (400).

This invention discloses a mode filter, a few-mode fiber amplifier, and a multi-stage fiber amplifier system. The mode filter is fused to a polarization-maintaining ytterbium-doped few-mode fiber using a fiber fusion splicer. The cross-section of the mode filter includes: a core region with a core diameter smaller than that of the few-mode fiber; a cladding region surrounding the core region; two stress bars disposed on the cladding region and arranged symmetrically relative to the upper and lower axes of the core region; and Bragg gratings symmetrically distributed and etched along the edge of the core region, with the position of the Bragg gratings coinciding with the higher-order transverse mode portions transmitted within the core region. This invention uses a grating writing device to etch the Bragg grating structure around the core of the few-mode fiber, matching the target position of the grating on the fiber cross-section with the distribution of the higher-order transverse mode fields in the fiber. This results in greater loss of the higher-order modes in the fiber after passing through the grating, thus achieving the function of mode filtering.

The present invention relates to the field of optical fiber sensing technology, and specifically discloses a fire protection pipeline monitoring method and system based on optical fiber sensing, and an optical fiber, comprising: winding an optical fiber around a fire protection pipeline to be monitored, connecting one end of the optical fiber to a light source output end, and connecting the other end of the optical fiber to a vibration signal acquisition end; outputting signals of different frequency bands from the light source output end, and then acquiring the spectrum signal of the fire protection pipeline by the vibration signal acquisition end; normalizing the spectrum signal, mapping the amplitude data of the spectrum signal to between [0, 1]; performing wavelet packet decomposition on the normalized data using the db6 wavelet basis function and calculating the wavelet energy ratio of each wavelet packet node. The inverted triangle tip velvet structure in the present invention amplifies the mechanical vibration of a 0.1mm crack in the pipeline by more than three times through the geometric stress concentration effect, and the acoustic impedance matching characteristics of the nanofilling layer reduce the signal transmission loss by 40%, and can also preliminarily filter out redundant noise signals.

The invention discloses a preparation method of an optical fiber for a high-temperature non-fading and non-migration optical cable, and relates to optical fibers. According to the invention, the curing monomer and 3-aminopropyl methyl dimethoxy silane are added into the acrylic resin of the inner coating layer, and the additive does not contain small molecular active substances, so that the migration phenomenon is avoided; and the amino siloxane can enhance the adhesion between the high-temperature-resistant acrylate layer and the polyimide layer. Secondly, maleic anhydride and 4, 4 '-diaminodiphenyl ether are used as reaction raw materials to synthesize a diamine monomer containing a bisimide element, a thermosetting polyimide film with a molecular main chain containing a dynamic imine bond is prepared through an amine-aldehyde condensation reaction, a primary amine group in an amino silane coupling agent is utilized, and the dynamic imine bond in the main chain of the thermosetting polyimide film is removed; the imine reversible bond exchange reaction is promoted, self-repairing is achieved, large-area layered stripping of a coating is repaired after the optical fiber is used for a long time, and the high temperature resistance of the optical fiber is improved. The optical fiber prepared by the invention has a high-temperature stable effect.

The invention discloses a full polarization-maintaining ultra-flat ultra-wideband super-continuum spectrum laser based on noise-like pulse pumping, and the laser comprises a full polarization-maintaining noise-like pulse seed source which outputs 1.55 [mu] m noise-like square wave pulse; the two-stage polarization-maintaining ytterbium-erbium-doped optical fiber amplifier is used for outputting a spectrum of 1.5-2.3 microns; the polarization-maintaining high-nonlinearity optical fiber realizes 0.9-2.9 [mu] m flat type super-continuum source output; the polarization-maintaining large-mode-field ytterbium-erbium-doped optical fiber amplifier is used for amplifying the 1.55 [mu] m position of the super-continuum source; the polarization-maintaining large-mode-field ytterbium-doped optical fiber is used for amplifying the 1.06 mu m position of the super-continuum source; a mode field adapter for matching the mode fields of the optical fibers; the polarization-maintaining photonic crystal fiber expands the short wave to an ultraviolet band; the metafluotellurate is used for maintaining the long wave to be 4 microns; and the spectrum of the polarization-maintaining sulfide optical fiber is further expanded to 12 microns. According to the invention, a full polarization-maintaining structure is adopted, and a super-continuum spectrum with high quality, high stability and high coherence can be output.

The invention relates to the technical field of optics, in particular to a photon nanometer jet flow generator based on a concentric ring structure and a design method, and the photon nanometer jet flow generator comprises a medium substrate and a medium concentric ring structure arranged on the medium substrate; the medium concentric ring structure is formed by circular ring structures with different inner and outer radiuses distributed along a concentric circle. According to the PNJ generator based on the concentric ring structure, the concentric ring structure meeting the requirement can be designed as required for any optimization target. Moreover, the concentric ring structure provided by the invention is compatible with a micro-nano processing technology, is easy to process, has the advantage of on-chip integration, and shows huge application potential in the fields of ultrahigh-resolution optical imaging, nano particle control, ultra-sensitive biosensing, nanoscale photoetching, enhanced spectroscopy and the like.

An MCF according to the disclosure has a structure preventing deterioration in quality of optical transmission signals. The MCF comprises cores, a common cladding, and a coating. Any of the cores has a coating leakage loss of 0.01 dB / km or more at a wavelength within a wavelength range of from 850 nm to 1700 nm. The coating includes a leaked light propagation suppressive coating layer having a first optical property or a second optical property to light with a wavelength within a wavelength range of from 850 nm to 1700 nm or from 1260 nm to 1625 nm. The first optical property is defined by, as an attenuation index of the light, an absorbance per 1 µm thickness being 0.1 dB or more. The second optical property is defined by a product of absorbance per 1 µm thickness and a thickness being 0.1 dB or more.