1768 results about "Isolator" patented technology

A microresonator is provided that incorporates a composite material comprising a polymer matrix and nanoparticles dispersed therein. The microresonator includes the composite material having a shape that is bounded at least in part by a reflecting surface. The shape of the microresonator allows a discrete electromagnetic frequency to set up a standing wave mode. Advantageously, the polymer matrix comprises at least one halogenated polymer and the dispersed nanoparticles comprise an outer coating layer, which may also comprise a halogenated polymer. Methods for making composite materials and microresonators are also provided. Applications include, for example, active and passive switches, add/drop filters, modulators, isolators, and integrated optical switch array circuits.

An isolator comprising a shaft (10), a pulley (20) journalled to the shaft on a first bushing (40) and a second bushing (50), the shaft comprising a shaft stop (12) disposed on a shaft radially outer surface (14), the pulley and the shaft rotationally moveable relative to each other, the pulley comprising an inner hub (23), the inner hub having a pulley stop (24) disposed to cooperatively engage the shaft stop, a torsion spring (30) engaged with the shaft and the pulley, the torsion spring exerting a contractive force parallel to an axis of rotation (A-A) in order to retain the pulley on the shaft, a cover member (60) fixed to the shaft, the pulley urged into engagement with the cover member by the torsion spring axial contractive force, and a rubber member (80) disposed on the shaft stop for engaging the pulley stop.

The invention discloses a microwave power source and a microwave ablation therapeutic instrument, which relate to a full-solid-state microwave power generating circuit and a microwave therapeutic instrument circuit. The microwave power source adopts a full-solid-state circuit close-loop control to achieve stable microwave power output and continuous adjustable microwave power. The microwave energy can generate enough penetration depth in human tissue to enlarge the ablation range. The ablation range of 915 MHz microwave frequency band is larger than that of 2,450 MHz microwave frequency band, so that the 915 MHz microwave frequency band is more suitable for ablation therapy. The microwave power source comprises a microwave signal generator, a power control time adjusting circuit, an impedance matcher, a drive circuit, a power splitter, a plurality of power amplifiers, a power mixer, an isolator and a power tracking and detecting circuit. The microwave ablation therapeutic instrument is constituted by the microwave power source and a microwave ablation pin under control of a microprocessor.

A distributed optical fiber sensor based on Raman and Brillouin scattering is provided. The distributed optical fiber sensor includes a semiconductor FP cavity pulsed wideband optical fiber laser (11), a semiconductor external-cavity continuous narrowband optical fiber laser (12), a wave separator (13), an electro-optic modulator (14), an isolator (15), an Er-doped optical fiber amplifier (16), a bidirectional coupler (17), an integrated wavelength division multiplexer (19), a first photoelectric receiving and amplifying module (20), a second photoelectric receiving and amplifying module (21), a direct detection system (22), a narrowband optical fiber transmission grating (23), a circulator (24) and a coherence detection module (25). The temperature and the strain can be measured simultaneously, and the signal-to-noise ratio of the system is enhanced.

The invention belongs to the field of mechanical vibration isolation and particularly relates to a multiple-degree-of-freedom vibration isolator and a multiple-degree-of-freedom vibration isolating system for an effective load and a satellite. The multiple-degree-of-freedom vibration isolator provided by the invention consists of a casing, a motion guide rod, a metal wire network material member,flexible hinges, a fine tuning spring, an upper casing end cover and a lower casing end cover and has the advantages of compact structure, reliable performance, long service life and the like. The vibration isolating system consisting of the vibration isolator arranged according to a certain geometry configuration is arranged between the effective load and the satellite and can be used for isolating the vibration transmitted to the effective load from each direction of a satellite platform; and the vibration isolator is connected with the effective load and the satellite through the flexible hinges, and thus a gap, collision and the like are avoided.

The invention relates to a spring rubber vibration-isolation hanger used for vibration reduction and noise reduction of heating ventilation pipes, which is installed on the indoor top of a building. The hanger includes a first frame, a vibration isolation pad laid on the inner wall of the first frame and tightly wrapping the abdomen of the heating ventilation pipe, and two sets of suspension vibration isolation components. The first frame includes a U-shaped pipe clip and a crossbeam located below the heating and ventilation pipe and fixedly connected to the opening end of the U-shaped pipe clip to form a closed frame structure with the U-shaped pipe clip. The suspension vibration isolation assembly includes an upper suspension rod, a spring vibration isolator and a lower suspension rod connected vertically in sequence. The invention can not only play a good role in vibration isolation and shock resistance for the whole heating and ventilation pipe, but also can play a good role in vibration isolation and noise reduction for the local air pipe, and is especially suitable for the main control room of the nuclear power plant and the film and television workstation, etc. It is suitable for occasions that have higher requirements for indoor equipment safety and acoustic environment.

The invention relates to the technical field of fiber sensing, and especially to a pre-pumped pulse and Gray code based BOTDA instrument. The BOTDA instrument comprises a narrow-linewidth semiconductor sensor, a coupler, a first erbium doped fiber amplifier, a first polarization controller, a single sideband modulator, a microwave source, an optical isolator, a sensing fiber, an optical annular device, a second erbium doped fiber amplifier, a polarization scrambler, an electro-optical intensity modulator, a second polarization controller, an arbitrary waveform generator, an optical filter, a photoelectric detector and a signal collecting and processing system. On the premise that the high spatial resolution of a BOTDA system is maintained, the BOTDA instrument ensures the sensing distance and the measuring precision of the system, and improves the sensing performance of the system.

The present invention provides a system and method for optimizing the performance of 13.56 MHz frequency RFID tags in conjunction with metal substrates. Briefly, a thickness exists for each type of RFID isolator material at which the performance of a 13.56 MHz RFID tag is optimal when used with metal. Varying from this optimal value, in either the positive or negative direction adversely affects read distance. A method of determining this optimal thickness is disclosed, as well as an RFID tag or a substrate being used in conjunction with a material of this thickness.

The invention discloses an all-optical wavelength converting device based on non-linear optical waveguide. The device comprises a first optical coupler, an erbium-doped optical fiber amplifier, a polarization controller, a PPLN waveguide, an optical isolator, a second optical coupler and a pump optical wavelength selector, which are connected in sequence by optical paths in clockwise direction to form an annular cavity laser with the built-in PPLN optical waveguide. The first optical coupler and the second optical coupler respectively provide a signal light input port and a converted idle light output port for the external. The non-linear optical waveguide is the PPLN optical waveguide and the pump optical wavelength selector is a dual wavelength selector or a multiple wavelength selector. The pump light produced by signal light and the inner of the annular cavity by lasing carries out non-linear mutual interaction in the PPLN optical waveguide to generate converted idle light, so as to realize wavelength converting. The device can realize tunable wavelength converting of single-channel to dual-channel and single-channel to multi-channel (broadcasting type) and input and output tunable wavelength converting with the advantages of flexible converting function, compact and easily realizable structure and low cost.

A fiber amplifier having two erbium doped fiber coils and a pump laser diode optically coupled, through a fiber array, to a planar lightwave circuit, is described. A photodetector array, a multiport free-space optical isolator, and a strip of thin-film gain flattening filter are attached to a side surface of the planar lightwave circuit, which has a tunable optical power splitter for variably splitting the optical pump power for the laser diode between the two erbium doped fiber coils, and variable tilters for correcting the gain tilt of the amplifier. The variable splitter and the tilters are thermally tunable Mach-Zehnder interferometers.

A plurality of heavy mass irregularities attached to an inner wall of the drill collar attenuate waves traveling through the collar. The plurality of heavy mass irregularities are spaced and sized for the maximum attenuation of acoustic pulses in a predetermined frequency range. The mass irregularities may be rings firmly coupled to the outer surface of the collar. Alternatively, the mass irregularities may be rings firmly coupled to the outer collar surface by neck pieces, extending inwardly from the inner circumference of the ring. The mass irregularities may be made of steel or tungsten. In another preferred embodiment, the mass irregularities are asymmetrically coupled to an outer collar wall for providing preferential directional attenuation.

The invention discloses an ultra narrow linewidth low noise high power single frequency fiber laser which comprises a single mode semiconductor laser pumped source, a polarization-maintaining wavelength division multiplexing device, a coupling output polarization maintaining fiber raster, a high reflection polarization maintaining fiber raster, a wave plate, a high gain fiber, a low reflection narrow linewidth fiber grating, a dichroscope, a heat sink, a sealed air chamber and a fiber clamp and polarization maintaining fiber isolator. A common end of the polarization-maintaining wavelength division multiplexing device connects with the coupling output polarization maintaining fiber raster. The coupling output polarization maintaining fiber raster and the high reflection polarization maintaining fiber raster are etched on a same polarization maintaining fiber or respectively etched on two strips of polarization maintaining fibers with consistent fast and slow shaft directions in connection, the high reflection polarization maintaining fiber raster connects with the high gain fiber through the wave plate, the high gain fiber connects with the low reflection narrow linewidth fiber grating, and the dichroscope in order. According to the invention, a folding composite chamber and a double virtual annular chamber are constructed in a short straight chamber structure, and a single frequency fiber laser with ultra narrow linewidth and polarization-maintaining output is generated.

The invention discloses a positive and negative stiffness parallel quasi-zero stiffness vibration isolator which comprises an upper top plate, a lower top plate, a positive stiffness element and multiple negative stiffness elements, wherein the positive stiffness element and the multiple negative stiffness elements are located between the upper top plate and the lower bottom plate. The positive stiffness element is installed on a base plate, the base plate is fixed to the lower bottom plate and used for adjusting the height of the positive stiffness element, and the multiple negative stiffnesselements are evenly distributed on the left side and the right side of the positive stiffness element. In each negative stiffness element, an inner magnetic ring set and an outer magnetic ring set are both located in a magnetic ring sleeve, the magnetic ring sleeve is fixed to the lower bottom pate, a magnetic ring shaft is located in the axial center of the magnetic ring sleeve, the magnetic ring shaft is fixedly sleeved with the inner magnetic ring set, the inner magnetic ring set is sleeved with the outer magnetic ring set, the outer magnetic ring set is fixed to the magnetic ring sleeve,the top end of the magnetic ring shaft is connected with a metal pulling and pressing rod, the metal pulling and pressing rod is coaxial with the magnetic ring shaft, a pulling and pressing rod pressing block is fixed to the top end of the metal pulling and pressing rod and fixed to the upper top plate, and the inner magnetic ring set and the outer magnetic ring set are axially magnetized. The vibration isolator can achieve ultra-low-frequency vibration isolation.

The invention relates to an optical fiber communication network failure monitoring technology, in particular to a device and a method for monitoring failures of a time division multiplexing optical network link, and solves the problems that the present time division multiplexing passive optical network failure monitoring technology is low in spatial resolution, complicated in structure, low in sensitivity and small in dynamic range. The device comprises a time division multiplexing optical network and a monitoring device, wherein the time division multiplexing optical network comprises an optical line terminal, a feeder fiber, an n-branch optical splitter, n branch fibers and n optical network units; the monitoring device comprises an isolator-free semiconductor laser, a coupler, an optical coupling device, a photoelectric detector, a signal acquisition and treatment device and n optical feedback devices. The semiconductor laser is connected with the coupler, and the large-scale output terminal of the coupler is connected with the input terminal of the optical coupling device. The device is suitable for monitoring failures of a time division multiplexing passive optical network.

The invention relates to a short-wave frequency searching device which comprises a broadband receiving unit, a digital down-conversion module, a digital signal processing module, a main control module, an interface module and a power supply module; wherein the broadband receiving unit comprises an antenna isolator and a short-wave broadband receiving module; the digital down-conversion module is used for collecting an intermediate frequency signal provided by the broadband receiving unit, and transforming the intermediate frequency signal into a baseband signal to be provided to the main control module and the digital signal processing module; the digital signal processing module is used for achieving usable frequency searching and frequency optimizing, selecting an idle channel as a local optimal frequency through perceiving a frequency spectrum in a set frequency range, and selecting a sky wave usable frequency range through estimating the maximum usable frequency and the minimum usable frequency of the sky wave channel; the main control module is used for monitoring the working state, the usable frequency range, the optimal frequency and the frequency spectrum energy of the short-wave frequency searching device, presetting a communication frequency range or communication frequency and realizing man-machine interaction and controlling external devices; the interface module is used for providing a video interface, a remote control interface, a data communication interface, a GPS interface and a network interface; and the power supply module is used for providing a DC power for each module, device and unit.

The invention discloses a mode selection coupler based 8-shaped cavity mode locking column vector fiber laser including a pump source, a wavelength division multiplexer, a gain fiber, a single-mode fiber, a first polarization controller, a second polarization controller, a 3dB coupler, an isolator, a coupler and a mode selection coupler. The output terminal of the pump source is connected with a short wavelength input terminal of the wavelength division multiplexer. The output terminal of the wavelength division multiplexer is connected with a 1 port input terminal of the 3dB coupler through the gain fiber, the single-mode fiber and the first polarization controller successively. A 2 port input terminal of the 3dB coupler is connected with a long wavelength port of the wavelength division multiplexer. A 4 port is connected with a 3 port of the 3dB coupler through the isolator, the coupler and the mode selection coupler successively. Therefore, an 8-shaped resonance cavity is formed. The second polarization controller is connected with a less-mode fiber output terminal of the mode selection coupler. The invention has advantages of being narrow in fiber laser output pulses, high in column vector laser polarization purity, small in loss and low in cost.

The invention relates to a fiber optical parametric oscillator for achieving Fourier domain mode-locked laser output. Seed light output by two semiconductor lasers is modulated by phase and amplified by a high power optical amplifier to serve as pump light, the pump light is output from the pump output end of a wavelength division multiplexer and enters high nonlinear fiber through a polarization controller, and a part of the pump light is transferred into signal light in the high nonlinear fiber due to fiber nonlinear effect. After the signal light passes through a second optical isolator, dispersion-shifted fiber and a tunable filter, most energy is fed back to the high nonlinear fiber from a high power shunt ratio output end of an optical coupler with 9:1 power shunt ratio through the wavelength division multiplexer so as to form resonance laser output. When modulation frequency of the tunable filter is equal to fundamental frequency of a laser resonant cavity, the Fourier domain mode-locked laser output can be obtained. The fiber optical parametric oscillator achieves the Fourier domain mode-locked laser output, has significant application value in the fields of optical tomography, fiber bragg grating sensing and the like, and has the advantages of being high in wavelength scanning frequency, flexible in laser output spectrum tuning range control and the like.

The invention discloses a microwave photon up-conversion device and method based on a photoelectric oscillator and belongs to the technical field of microwave photonics. The device is composed of a laser source, a first coupler, a first circulator, a first high nonlinearity dispersion displacement optical fiber, an erbium-doped optical fiber amplifier, a first photoelectric detector, a second coupler, a first Mach-Zehnder modulator, a first microwave signal source, a first direct current voltage-stabilized power supply, an optical filter, a second Mach-Zehnder modulator, a second direct current voltage-stabilized power supply, a second circular, a second high nonlinearity dispersion displacement optical fiber, a second photoelectric detector, a microwave amplifier, a double-parallel Mach-Zehnder modulator, a third direct current voltage-stabilized power supply, a fourth direct current voltage-stabilized power supply, a fifth direct current voltage-stabilized power supply, an optical isolator and a spectrum analyzer. A Brillouin frequency shift value f of the high nonlinearity optical fiber is 9.2GHz, and a signal with frequency of f<m> can be up converted to f<m>+18.4GHz, so alow quality and low frequency intermediate signal is converted into a high quality and high frequency signal.