139 results about "Microstructure fiber" patented technology

A novel method for high power optical amplification of ultrashort pulses in IR wavelength range (0.7-20 Ãm) is disclosed. The method is based on the optical parametric chirp pulse amplification (OPCPA) technique where a picosecond or nanosecond mode locked laser system synchronized to a signal laser oscillator is used as a pump source or alternatively the pump pulse is created from the signal pulse by using certain types of optical nonlinear processes described later in the document. This significantly increases stability, extraction efficiency and bandwidth of the amplified signal pulse. Further, we disclose five new practical methods of shaping the temporal and spatial profiles of the signal and pump pulses in the OPCPA interaction which significantly increases its efficiency. In the first, passive preshaping of the pump pulses has been made by a three wave mixing process separate from the one occurring in the OPCPA. In the second, passive pre-shaping of the pump pulses has been made by spectral filtering in the pump mode-locked laser or in its amplifier. In the third, the temporal shape of the signal pulse optimized for OPCPA interaction has been actively processed by using an acousto-optic programmable dispersive filter (Dazzler) or liquid crystal light modulators. In the fourth alternative method, the signal pulse intensity envelope is optimized by using passive spectral filtering. Finally, we disclose a method of using pump pulses which interact with the seed pulses with different time delays and different angular orientations allowing the amplification bandwidth to be increased. In addition we describe a new technique for high power IR optical beam delivery systems based on the microstructure fibres made of silica, fluoride or chalcogenide glasses as well as ceramics. Also we disclose a new optical system for achieving phase matching geometries in the optical parametric interactions based on diffractive optics. All novel methods of the ultrashort optical pulse amplification described in this disclosure can be easily generalized to other wavelength ranges.

A microstructured fiber having a cladding comprising a number of elongated features that are arranged to provide concentric circular or polygonial regions surrounding the fiber core. The cladding comprises a plurality of concentric cladding regions, at least some of which comprising cladding features. Cladding regions comprising cladding features of a relatively low index type are arranged alternatingly with cladding regions of a relatively high index type. The cladding features are arranged in a non-periodic manner when viewed in a cross section of the fiber. The cladding enables waveguidance by photonic bandgap effects in the fiber core. An optical fiber of this type may be used for light guidance in hollow core fibers for high power transmission. The special cladding structure may also provide strong positive or negative dispersion of light guided through the fiber-making the fiber useful for telecommunication applications.

A Raman amplifier having a microstructured fiber and at least one pump laser, optically connected to one end of the microstructured fiber. The pump laser is adapted for emitting a pump radiation at a wavelength λ_p, and the microstructured fiber has a silica-based core surrounded by a plurality of capillary voids extending in the axial direction of the fiber. The core of microstructured fiber has at least one dopant added to silica, the dopant being suitable for enhancing Raman effect.

A preform for a microstructured fibre or a part for a preform for a microstructured fibre. The preform or part has a length in the longitudinal direction and a cross section perpendicular thereto, and includes a rod arranged at the centre of the preform or part, with one or more tubes being concentric to the rod. The rod is sleeved inside a first of the concentric tubes, and the rod and/or at least one of the concentric tubes has grooves and/or slits extending in the longitudinal direction, with the number of innermost longitudinally extending grooves and/or slits with respect to a centre of the preform or part being at least six.

The invention provides throughput type fiber optical tweezers based on a coaxial dual-waveguide structure and a preparation method. The throughput type fiber optical tweezers mainly comprise a coaxial double-waveguide microstructure fiber [1], an LD light source with the output wavelength of lambda 1, an LD light source [3] with the output wavelength of lambda 2, a wavelength division multiplexing device [4] and a standard single-mode fiber [5]),wherein the output ends of the light source [2] and the light source [3] are connected with the two input ends of the wavelength division multiplexing device [4]; the output end of the wavelength division multiplexing device [4] is coupled with the coaxial double-waveguide fiber [1]; and the other end of the coaxial double-waveguide fiber [1] is finely ground to obtain the cone structure. The invention controls the particles by utilizing the coaxial double-waveguide fiber, changes the luminous power of the light source by adjustment, and can realize throughput, transmission and resorption of stable trapped particles; and meanwhile, the invention can trap the particles in a more flexible and accurate way, has adjustability, and greatly enhances the practicality of the fiber optical tweezers.

An optical fiber having microstructured terminal end suitable for reducing Fresnel losses. In an exemplary embodiment, the microstructured surface includes a plurality of protrusions, recesses or combinations thereof that effectively and incrementally change the refractive index of the terminal end of the optical fiber such that the refractive index is gradually drawn closer to the refractive index value of the surrounding environmental medium.

This invention pertains to a glass fiber, a Raman device and a method. The fiber is a hollow core photonic bandgap chalcogenide glass fiber that includes a hollow core for passing light therethrough, a Raman active gas disposed in said core, a microstructured region disposed around said core, and a solid region disposed around said microstructured region for providing structural integrity to said microstructured region. The device includes a coupler for introducing at least one light signal into a hollow core of a chalcogenide photonic bandgap fiber; a hollow core chalcogenide photonic bandgap glass fiber; a microstructured fiber region disposed around said core; a solid fiber region disposed around said microstructured region for providing structural integrity to said microstructured region; and a Raman active gas disposed in the hollow core. The method includes the steps of introducing a light beam into a hollow core chalcogenide photonic bandgap glass fiber filled with a Raman active gas disposed in the core, conveying the beam through the core while it interacts with the gas to form a Stokes beam of a typically higher wavelength, and removing the Stokes beam from the core of the fiber.

The invention relates to a fiber sensor, particularly relates to a multifunctional sensor with microstructure fiber surface plasma resonance and a preparation method thereof. The two sides of the photonic crystal fiber substrate of the fiber are provided with fan-shaped openings that surface of which are plated with gold films. Tips of the bottom ends of the fan-shaped openings are provided with silver nanowires. The core of the photonic crystal fiber substrate is provided with a magnetic fluid, and the outer side of the core is provided with a cladding air hole. The preparation method comprises the steps of: polishing the fan-shaped openings on the photonic crystal fiber; filling the silver nanowires; uniformly plating the gold films on the surface of the fan-shaped openings; pressing themagnetic fluid into the photonic crystal fiber from a small tube; and coupling and splicing the two ends of the common single mode fiber and the photonic crystal fiber through the self-calibrating function of the a fiber fusion splicer. The sensor of the invention can achieve the analysis and detection of the external magnetic field intensity, the refractive index of the to-be-measured liquid andthe external temperature in one time, therefore, the technical defects that the conventional detection technology is complex in operation, low in detection sensitivity and non-real time online detection are overcome.

The invention discloses a plasma resonance microstructure fiber sensor which comprises a light source, two ordinary single mode fibers, a microstructure fiber and a photoelectric detector, wherein, the light source, the first ordinary single mode fiber, the microstructure fiber, the second ordinary single mode fiber and the photoelectric detector are connected sequentially; the microstructure fiber is formed by photonic crystal fiber taper which has paralleled hexagon cross section and two-dimensional periodic structure; a metal membrane and a protein polymer membrane are coated on the surface of the tapered section from inside to outside sequentially; and the periodic structure consists of a background medium and dielectric rods which are distributed and arranged in the background medium periodically. As the usage of a microstructure fiber cladding light guiding mechanism, the fiber sensor can not only educe a guided mode without peeling cladding, but also realize high coupling efficiency of optical power of incident wave entering surface plasma resonance wave without a buffer layer. The invention has the advantages of simple process, compact structure, high measuring accuracy, strong anti-interference ability, being capable of being operated in harsh environment, and the like.

The invention belongs to the technical field of temperature sensors and provides a temperature sensor based on microstructure fibers, the manufacturing method of the temperature sensor, and a temperature measuring device. The temperature sensor comprises at least two microstructure fibers, wherein every two adjacent microstructure fibers are connected in series through a multimode fiber. For a fiber core and a cladding of each microstructure fiber, air holes distributed in the axial direction are formed in the cladding at least. Quantum dot materials are arranged in the air holes. The wavelength of fluorescent light emitted by the quantum dot materials in a microstructure fiber is different from the wavelength of fluorescent light emitted by the quantum dot materials in another microstructure fiber. Compared with ordinary fluorescent materials, the quantum dots have the advantages of being large in excitation wavelength, adjustable in fluorescent wavelength, stable in fluorescent intensity and the like. By adding quantum dots in different types and sizes into the microstructure fibers, the microstructure fibers can be distinguished in a wavelength domain according to the fluorescent wavelengths, and quasi-distributed sensing is realized.

The invention relates to the technical field of low-concentration gas detection and in particular relates to a trace nitrous oxide gas detection device. The device comprises an infrared laser output module, an N2O absorption gas chamber and a signal processing module, wherein the central wavelength of laser output by the infrared laser output module is matched with the position of an N2O gas absorption peak; the N2O absorption gas chamber comprises a hollow microstructure fiber; micro pores are formed in the peripheral wall of the hollow microstructure fiber along the radial direction; the laser output by the infrared laser output module is transmitted to one end of the hollow microstructure fiber by virtue of a single mode fiber; laser subjected to N2O gas absorption in the hollow microstructure fiber is output to the signal processing module from the other end of the hollow microstructure fiber by virtue of a multimode fiber; and the N2O gas content is calculated by the signal processing module according to the laser loss. The problem that the light path is short is fundamentally solved when the gas concentration is detected by a tunable laser spectral absorption method; and moreover, the transmission loss is avoided, and the accuracy and reliability of the measurement result are improved.

A fiber optical parametric oscillator is formed using photonic crystal fibers, also known as microstructure fibers or holey fibers. The optical parametric oscillator includes only a few meters of microstructure fiber. In one embodiment, the microstructure fiber is disposed between a highly reflective mirror and a diffraction grating in a simple Fabry-Perot configuration wherein the diffraction grating is tuned to reflect a particular wavelength of the signal wave back to the microstructure fiber. In another embodiment, the microstructure fiber is disposed in a ring cavity and the parametric oscillator is synchronously pumped. The parametric oscillator may be implemented with free space optics or use all fiber optic components.

This application describes methods and apparatus for fiber optic distributed acoustic sensing (DAS) where microstructured fiber (202), such as holey fiber or photonic crystal fiber is used as the sensing fiber (104). The microstructured fiber is configured so to provide at least one of enhanced sensitivity to a given incident acoustic signal; an enhanced non-linear optical power threshold and directional sensitivity. By configuring the microstructured fiber to be more compliant than an equivalent solid fiber and/or provide a large refractive index variation in response to applied strain, the response to a given acoustic stimulus may be larger than for the equivalent fiber, Providing a hollow core may allow higher optical powers and by providing a directionality to microstructured (304) allows the fiber to be used in a DAS system with a directional response.

The invention discloses a hollow-core photonic band-gap fiber based on isolated anti-resonance layers and belongs to the technical field of microstructure fibers. A preparation method of the hollow-core photon band-gap fiber specifically comprises the steps that a complete stacked structure is formed through stacking of capillary tubes; after the capillary tube at the center of the stacked structure is removed, a fiber core glass tube is inserted; the periphery of the complete stacked structure is sleeved with a quartz sleeve to form a fiber preform rod; and the fiber perform rod is drawn through an existing hollow-core photonic band-gap fiber drawing method, a structure with the independent isolated anti-resonance layers is formed at the periphery of a fiber core, and thus the hollow-corephotonic band-gap fiber based on the isolated anti-resonance layers is formed. According to the hollow-core photonic band-gap fiber based on the isolated anti-resonance layers, the fiber core wall atthe fiber core is constituted by the isolated anti-resonance layers, limitation to light is enhanced, the scattering loss is reduced, and coupling between the hollow-core photonic band-gap fiber anda common single-mode fiber is facilitated.

The invention provides a phase change temperature control fiber. The phase change temperature control fiber is characterized by comprising a microstructure fiber matrix and a phase change material, wherein the microstructure fiber matrix comprises three-dimensional communication holes, the phase change material fills the three-dimensional communication holes, and each three-dimensional communication hole is of a three-dimensional structure with two or more holes communicating with each other. Compared with the prior art, the phase change temperature control fiber has the following advantages:first, the filling loading capacity and cycling stability of the phase change material are improved through the fiber structure design; second, through fiber surface treatment and fiber internal doping technology, good water resistance and mechanical properties of the fiber are realized; finally, the phase change composite hydrophobic temperature control fiber provided by the invention has the functions of keeping warm and cooling in the aspect of temperature regulation and control; in the aspect of material selection, the universality is achieved, most of commercial fiber materials can be adopted, then the fiber is suitable for industrial amplification application, and meanwhile, different materials can be designed according to actual needs; and in the aspect of fabric forming, a phase change temperature control fabric can be directly woven by the phase-change fiber, and also can be woven after yarns are prepared.

The invention provides a high sensitivity compact M-Z interference temperature sensor and a manufacturing method thereof; the sensor comprises an input single-mode fiber, a microstructure fiber and an output single-mode fiber connected in sequence; the microstructure fiber is placed under a tested environment; the fiber core of the input single-mode fiber is respectively connected with the microstructure fiber core and an air hole filled with a high heat optical coefficient medium, thus using the microstructure fiber core to transmit partial the input single-mode fiber output light to the output single-mode fiber, and using the microstructure fiber air hole filled with the high heat optical coefficient medium to transmit the residual light to the output single-mode fiber; the output single-mode fiber transmits the received light to a spectral analyzer for spectral analysis, thus determining the temperature of the tested environment according to the spectral analysis result. The high heat optical coefficient medium is filled in the microstructure fiber, thus providing the high sensitivity super compact structure M-Z temperature sensor.

The invention relates to a hollow-core microstructure fiber with high damage threshold, which can transmit high-energy and high-power pulse laser. An inner cladding composed of 11 to 15 quartz micro capillaries arranged at intervals is arranged around the inner wall of a quartz glass tube of an outer cladding; the parts of the 11 to 15 quartz micro capillaries, in contact with the inner wall of the quartz glass tube, are fixed on the inner wall of the quartz glass tube in a welding manner; the middle parts of the 11 to 15 quartz micro capillaries, namely the innermost layers, are a fiber core area with low refractive index; and the fiber core area with low refractive index is filled with inert gas or air or vacuum. The hollow-core microstructure fiber has the beneficial effects that the inner cladding is composed of 11 to 15 mutually separated quartz micro capillaries, namely hollow-core microstructure fibers; and light is transmitted in a hollow-core fiber core by using an anti-resonance guide principle in the structure, so that most of the transmitted light energy exists in the fiber core with low refractive index, the damage threshold of the fiber is improved, and the foundation is laid for laser transmission with high energy and high power.

The invention relates to a sensing head of a fluorescent fiber sensor. The sensing head of the fluorescent fiber sensor is of a wheel-shaped microstructure and comprises a fiber core, a coating layer and an air hole, wherein the fiber core and the coating layer are connected through tiepieces; and the inner wall of the air hole is coated with one layer of nanogold/methyl methacrylate with the thickness of 20 nm. A preparation method of the sensing head of the fluorescent fiber sensor comprises the following steps: preparing the nanogold/methyl methacrylate; coating the nanogold/methyl methacrylate on the inner wall of the air hole of the wheel-shaped microstructure fiber; and after coating is finished, roasting for 6 hours by controlling the temperature to be 50 DEG C so as to volatilize a dichloromethane solvent to obtain the sensing head of the fluorescent fiber sensor. Compared with the like products, the sensing head of the fluorescent fiber sensor has the advantages that the lower limit and the sensitivity of fluorescent detection of the sensing head can be increased by 20 times; the required sample amount is at nL amount order.

The invention discloses a microstructure fiber with fiber core modified by inverse opal (3DOM three dimensional ordered macroporous material). The method mainly comprises the following steps: preparing a PS or PMMA colloid microballoon solution, and adding a predecessor solution (TEOS or TiBALDH) into the colloid microballoon solution in a certain proportion; growing a segment of colloid crystal in a capillary with a Sol-gel cooperation self assembly method, forming predecessor gel when colloid crystal gap moisture is reduced, and sintering the capillary at high temperature in a box-type furnace and removing the colloid crystal to form an inverse opal composition; vertically cutting two common standard fibers after part coating is removed, inserting the two fibers into the capillary from two ends of the capillary to the inverse opal composition, fixing the fibers with glue, and fixing and packaging the capillary and fibers with a thermoplastic cannula. The microstructure fiber prepared in the invention can be used as a fiber filter and a biomedical sensing member. By using a common standard fiber in preparation, the microstructure fiber can connects a present fibre-optical communication network to facilitate the realization of all-optical sensing network. The microstructure fiber has the advantages of simple preparation, reliability and strong versatility.

The invention discloses a ring-shaped microstructure fiber which is formed by host material (1), first medium columns (2) and second refractive index medium columns (3). A fiber core (4) is located at the center of the fiber and is formed by host material. The centers of the first medium columns (2) are distributed on a circumference at equal intervals, wherein the circumference uses the center of the fiber as the circle center. The centers of the second medium columns (3) are distributed on another circumference at equal intervals, wherein the circumference uses the center of the fiber as the circle center. The distance between the centers of the first medium columns (2) and the center of the fiber is L1, the distance between the centers of the second medium columns (3) and the center of the fiber is L2, L1 is larger than 15 mu m, and L2 is larger than L1. The fiber uses the first medium columns (2) with small diameters to bind a fiber fundamental mode, uses the second medium columns (3) with large diameters to reduce bending loss of the fiber fundamental mode, and achieves the goals of a single mode, a large mode field and low bending loss transmission.