128 results about "Magneto-optic effect" patented technology

An optical waveguide isolator for use in an optical communication system is disclosed. The optical waveguide isolator comprises a semiconductive light amplifier structure including a semiconductor substrate of first conductivity type having a surface of a layer to be formed thereon, a first cladding layer of first conductivity type formed on the substrate, an active layer formed on the first cladding layer, a second cladding layer of the second conductivity type opposite to first conductivity type, formed on active layer, a first electrode formed on the surface of the semiconductor substrate opposite to the surface to be formed as a layer, and a second electrode formed on the second cladding layer; the first and the second cladding layers and the active layer form an optical waveguide in which the light wave propagates. The semiconductive light amplifier structure further comprises a light absorptive magnetic material layer having light absorption function for the light wave propagating through the optical waveguide. The magnetic material layer is magnetized so as to have the magnetic-field component in the direction which corresponds to the direction where a magnetic vector of the light wave vibrates, the waveguide structure body has a nonreciprocity optical characteristic that effective refractive index changes into the light wave to which the optical waveguide is propagated according to the magnet-optical effect of the light absorptive magnetic material layer according to the direction of propagation, by the effective refractive index change in the nonreciprocity, the attenuation of the first light wave that the optical waveguide is propagated in the first direction caused when the said waveguide is propagated, becomes small more than the attenuation of the second light wave propagated in the second direction opposite to the first direction caused when the said waveguide is propagated.

The invention provides a magneto-optic effect photon crystal fiber and manufacturing method thereof, wherein the fiber comprises a fiber core, a gas hole cladding layer and a covering layer, the fiber core material comprises pure quartz doping GeO2 having improved refractive index and rare earth Tb3, Al3 ions having increased Faraday magnetooptical effect, the gas hole cladding material comprises light quantum crystal structure capillary quartz tube in symmetrical hexagonal regular arrangement, the protective covering employs supported quartz tube. The optical fiber preparing process comprises the three steps of making doped terbium rare-earth optical fiber core stick, making optical fiber preformed stick and drawing magneto-optic effect photon crystal fiber.

The invention discloses an imaging ellipsometer based on magneto-optical effect, which relates to a film thickness measurement method and a device, particularly to a method and a device for observing the thickness distribution of a nano film on the surface of a sample. The ellipsometer is characterized in that a polarizer, a compensator and an analyzer capable of rotating in the direction of a transmission axis are adopted to correct a system, a magneto-optical modulation technology is adopted to change the polarization direction of the received light, a plane array detector is adopted to record the ellipsometry images of the film on the surface of the sample, iterative algorithm is adopted to process the data, and the shape parameters of the film on the surface of the sample are precisely measured. The imaging ellipsometer based on magneto-optical effect solves the defects of the prior art, improves the precision in detecting the polarization of the received light, and improves the measurement speed.

The invention discloses a tunable single-core Photonic Crystal Fiber (PCF) SPR single polarization wavelength splitter, relates to a tunable fiber wavelength splitter, belongs to the field of fiber communication and optical devices, and is suitable for the fields of wavelength division multiplexing / demultiplexing, fiber sensing and laser systems. The shortcomings of fixed wavelength splitting of a general PCF wavelength splitter, small bandwidth, insufficient mode coupling and failure to realize beam splitting using a single-core PCF are overcome. In a single-core PCF (7), symmetrical upper (2-1) and lower air holes (2-2) are plated with metal materials (8-1, 8-2) on the inner side walls thereof. According to an SPR mixed mode coupling effect and a single polarization filtering property, when the light containing A and B wavelengths enters the PCF (7), the X polarized light of the light of the A wavelength is lost and Y polarized light is output, the light of the B wavelength is the other way around, and thus the light of the two wavelengths is split. In addition, according to a magneto-optic effect, the magnetic fluid refractive index in an oval air hole (3) varies with a magnetic field, and finally, the single polarization wavelength splitting is enabled to be tunable.

The invention discloses an optical current sensor based on the Faraday magneto-optic effect. The optical current sensor comprises a laser generator which is used to generate polarized laser of a set wavelength, an integrated probe which comprises a magneto-optical medium, a photodetector which is used to convert an optical signal into an electrical signal, and a data analyzing and processing device which filters out noise through the combination of hardware filtering and software filtering to acquire a good response effect. A polarizer and an analyzer are arranged on two ends of the magneto-optical medium respectively, and are insulatedly packaged on both ends of the magneto-optical medium respectively. The laser generator and the polarizer are connected through an optical fiber path, andthe photodetector and the analyzer are connected through an optical fiber path. The invention further discloses a current measurement method of the optical current sensor based on the Faraday magneto-optic effect.

An integrated fiber optic switch based on the magneto-optic effect of magnetic materials suitable for optical fiber networks is presented. The switch is based on the Faraday Effect exhibited by magneto-optic materials. The all-fiber magneto-optic switch has a beam splitter at the input that splits an incoming signal into orthogonal polarized paths. Each path has at least one magneto-optic Faraday rotator (MOFR) controlled by a field. When the field is present, the polarization of the optical beam changes, thereby turning the switch on or off. A beam coupler couples the orthogonal polarized paths at the output of the all-fiber magneto-optic switch. The switch is constructed in the Mach-Zehnder configuration, utilizing two 3 dB couplers, isolators and MOFRs fabricated on silicon-on-insulator.

The invention relates to a device and a method for suppressing stimulated Brillouin scattering based on magneto-optical effect, which can suppress the occurrence of stimulated Brillouin scattering by using a magneto-optical rotation medium to periodically change the polarization state of a laser beam.

The invention discloses an optical fiber current sensing measurement system based on optical fiber magneto-optical effect, comprising a light source, a first transmission optical fiber, an optical fiber sensor head, a second transmission optical fiber and a photoelectric conversion and signal processing unit; the optical fiber sensor head comprises a polarization beam splitter, a Faraday rotator and an annealing optical fiber ring with a holophote; the light source transmits the light to the optical fiber sensor head by the first transmission optical fiber; wherein, the annealing optical fiber ring anneals under high temperature so as to eliminate dual-refraction in the optical fiber and improve the stability of the sensor head under the change of environmental temperature. The photoelectric conversion and signal processing unit is connected with the sensor head by the second transmission optical fiber.

A magnetically coupled pressure display system particularly adapted for pneumatic tires of motor vehicles includes pressure transducer coupled for rotating a magnet field source within the tire and an external magneto-optical liquid crystal display attached to or integrally incorporated into the exterior sidewall of the tire for visually indicating pressure within the tire responsive to the orientation of the magnetic field source within the tire. The external display exploits the magneto-optical effects of liquid crystals and can be conformally and permanently attached to the outer tire sidewall surface. Elements (pixels) comprising the display have selective light polarization properties globally determined by direction (orientation) of the magnetic field each experiences, the primary component of which is that provided by the magnetic field source rotated by the pressure transducer within the vehicle tire.

The invention provides an optical analog-to-digital converter based on polarization modulation, belonging to the field of photoelectric technology, and relates to a photoelectric signal processing and optical analog-to-digital converter. N-path current modulation signals uniformly divided by a sampling analog current signal are respectively input to a magnetic induction coil by an amplifying circuit; pulsed light emitted by a laser is polarized into a linearly polarized light by a polarizer, and the linearly polarized light is divided into N light path signals by a beam splitter, and the N light path signals are respectively input to N photoelectric branch circuits; the optical signal of each photoelectric branch circuit firstly passes through magneto optic effect material in the magnetic induction coil, and then is analyzed by an analyzer into an optical signal which is converted into an electrical signal by a photoelectric detector, the electrical signal is amplified by an amplifier and is input to the corresponding comparer to carry out threshold value judgment, and a digital signal is finally output by the comparer. The converter can realize the output of the digital signal with the traditional binary code and Gray code, and has the advantages of rapid sampling speed, more effective number bits, no restriction of the binary code and the Gray code, simple structure and low cost.

The present invention relates to a magnetooptical device utilizing a magnetooptical effect provided by using a magnetic garnet material, and provides a magnetic garnet material which is less likely to crack during the growth and lapping of the single crystal film. It is an object of the invention to provide a magnetooptical device which defines a Faraday rotation angle theta expressed by 44 deg.<=theta<=46 deg. when light having a wavelength lambd (1570 nm<=lambd<=1620 nm) impinges thereupon, in order to permit the suppression of and which is less likely to crack during processing to allow any reduction of yield. A magnetic garnet material expressed by a general formula: BiaM13-aFe5-bM2bO12 is used. M1 is at least one kind of element that is selected from among Y, La, Eu, Gd, Ho, Yb, Lu and Pb; M2 is at least one kind of element that is selected from among Ga, Al, Ti, Ge, Si and Pt; and a and b satisfy 1.0<=a<=1.5 and 0<=b<=0.5, respectively.

The invention discloses a rare earth alkaline earth borate, and the chemical formula of the rare earth alkaline earth borate is LiMRe 2 (BO 3 ) 3 , wherein M represents an alkaline earth element, the alkaline earth element is Sr or Ba, Re represents a rare earth element, and the rare earth element is selected from Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu One or more of them, the single crystal belongs to the trigonal crystal system. The invention also discloses a preparation method. The prepared rare earth alkaline earth borate crystal is stable in the air, not easy to deliquescence, and insoluble in water; the rare earth alkaline earth borate has important applications in the fields of optics and communication, such as magneto-optical isolation The device can be used to produce the Faraday magneto-optic effect and produce fluorescence as a phosphor matrix.

A fiber optic switch based on the magneto-optic effect of magnetic materials is presented. Due to the optical fiber based construction of the switching device it is suitable for optical fiber networks The on-off function of the switch is useful for isolation and connection of node(s) from a fiber optical network without having to turn off a laser. The switch is based on the Faraday Effect exhibited by magneto-optic materials. The all-fiber magneto-optic switch has a beam splitter at the input that splits an incoming signal into orthogonal polarized paths. Each path has at least one magneto-optic Faraday rotator (MOFR) controlled by a field. When the field is present, the polarization of the optical beam changes, thereby turning the switch on or off depending on the initial polarization of the beam. A beam coupler couples the orthogonal polarized paths at the output of the all-fiber magneto-optic switch. The MOFR is a bismuth substituted iron garnet. In an alternate embodiment the switch is constructed in the Mach-Zehnder configuration, utilizing two 3 dB couplers, isolators and MOFRs. In an alternate embodiment the switch is fabricated on silicon-on-insulator.

The invention discloses a differential detection device for a coherent layout imprisoned magneto-optic effect. The differential detection device comprises a bias coupler, a laser, a solenoid, alkali metal atomic vapor bubbles, a polarization beam splitting crystal, a photoelectric cell and a second photoelectric cell. The invention also discloses a differential detection method for the coherent layout imprisoned magneto-optic effect. According to the method, differential detection is performed on a laser signal obtained after linearly polarized light and atoms are mutually interacted in a magnetic field; through the scheme, common-mode noises which are associated with laser amplitude noises and frequency noises can be inhibited, so that the signal-to-noise ratio of the signal is improved; therefore, the stability of the output frequency of a coherent layout imprisoned atomic clock is improved. A passive coherent layout imprisoned atomic clock realized by adopting the scheme has the advantages of simple structure, low cost, small size and the like, and is suitable for realizing small and micro atomic clocks. The invention also discloses the differential detection method for the coherent layout imprisoned magneto-optic effect.

A micro-fluidic faraday rotation reinforcer relates to a novel micro-fluidic faraday rotation reinforcer structure. The rotation reinforcer (8) consists of a rotation reflection cavity (7) and a polarized beam splitter prism (3) outside the rotation reflection cavity (7); wherein the rotation reflection cavity (7) consists of a partially reflecting mirror (4) and a total reflecting mirror (5) which are parallelly arranged and a magneto-optic medium (6) between the partially reflecting mirror (4) and the total reflector (5); when the light path passing through a sample is constant, a magnetic field (9) is added along the light propagation direction; according to the nonreciprocity of magnetooptical effect, the rotation reinforcer (8) is used for improving measuring sensitivity to micro rotation angle; and a light source (1) is arranged beside the polarized beam splitter prism (3). According to the nonreciprocity of Faraday magnetooptical effect, when the beam passes through the sample medium back and forth for a plurality of times, the rotation angle can be multiplied. The micro-fluidic reinforcer designed by the invention has the advantages of simple structure, easy manufacture and convenient integration.

The invention discloses a differential protection device based on a Faraday magneto-optical effect, relating to a differential protection device, belonging to the field of relay protection of a power system. According to the differential protection device, the problems that large error components can be generated in differential operation and an internal fault and an external fault inside a section can not be accurately judged in an existing differential protection device. The differential protection device comprises a light source, a first multimode fiber, a second multimode fiber, a first optical current sensor, a polarization maintaining optical fiber, a second optical current sensor and an electronic processing unit; the first optical current sensor comprises a first multimode optical fiber collimator, a polarizer, a first Faraday magnetic-optical element and a first polarization maintaining collimator; and the second optical current sensor comprises a second polarization maintaining optical fiber collimator, a second Faraday magnetic-optical element, a polarization analyzer and a second multimode optical fiber collimator. The differential protection device is used in relay protection of the power system.

The invention provides an all-optical-fiber current transformer and a current measuring method thereof. The all-optical-fiber current transformer is mainly formed by three parts: a sensing unit, a signal processing unit, and a merging unit. The sensing unit employs the Faraday magneto-optic effect principle and used for inducing current of a measured conductor, and generating light intensity signals carrying data information of the Faraday rotation angle. The signal processing unit mainly completes input of optical singles of the sensing unit, analysis of the output optical signals, digitalization processing, and temperature compensation etc., and performs output according to a prescribed synchronous serial mode. The merging unit completes synchronization, switching or parallel logic of information of the signal processing unit, and transmits the information to an electrical measuring instrument and a relay protection device.

The invention discloses a crystal current sensor based on composite optical vortex. A laser emission unit is used to emit a linear polarization state fundamental mode Gaussian beam, and a composite beam generating unit is used to divide the linear polarization state fundamental mode Gaussian beam into two beams, and is used to modulate the two beams into optical vortex beams, which are combined together, and are converted into circular polarization type composite optical vortex beams. A crystal sensing unit is used to transmit the composite optical vortex beams into a crystal along the optical axis of the crystal, and is used to apply the current to the crystal to generate a magnetic field along the direction of the optical axis of the crystal. A detection unit is used to detect the light intensity distributions of the composite optical vortex beams before and after the application of the magnetic field, and the deflection of the composite optical vortex beams occurs, and the current is calculated by calculating the deflection degree, and therefore a current sensing function is realized. The circular polarization state characteristic of the optical vortex during a transmission process is maintained, and the change of the beam polarization state by using Faraday magneto-optic effect can be directly displayed in composite spots, and therefore a problem of reduction of sensitivity of an optical fiber current sensor caused by linear birefringence is effectively solved.

This invention provides a kind of triple polarized detection method which can remove the linear birefringence influence in optic current transformer. It measures the light intensity in three direction of polarization of ellipse polarized light output by the optic current transformer, that is the data of the level polarized intensity, the uprightness polarized intensity and the 45 degree with the level direction polarized intensity, uses the triple measurement data calculates the phasic difference information between level polarized component and uprightness polarized component, separates and detect the Faraday effect and linear birefringence in real time. The triple ellipse polarized detection project of ellipse polarized light advances in this invention can realize that the measurement of the linear birefringence and the detected current be correct and in real time by using the Faraday magneto-optic effect optic current transformer, and it can be applied in more broad field of ellipse polarized light measurement.

A cyclic dynamic magnetizing optomagnetic synchronous magnetic light testing method synchronously imposes a linear polarization cyclic laser narrow pulse train and a cyclic alternating magnetic field to a magnetic sample. The cyclic alternating magnetic field realizes cyclic and dynamic magnetization of the magnetic sample. After the cyclic laser narrow pulse train reacts with the magnetic sample, polarization of transparent lights or reflected lights of the pulse train will change to measure magnetization variation of the magnetic sample. In addition, the cyclic laser pulse train synchronously triggers a time delayer to output a time delay of the same frequency and time to adjust a synchronous trigger cyclic alternating magnetic field with adjustable electric pulse train. Thus, the laser pulse reacting with the sample repeatedly measures a same magnetization stable in the cyclic alternating magnetization of the sample and converts the measuring in the dynamic magnetization into static measuring according to a principle specified in the attached figure 1. Scanning time delay realizes to measure a magnetizing period. The measuring sample discloses benefit and application of the present invention to magnetic deflection in ultra-fast demagnetization dynamics test.

A spatial light modulator includes: a magnetic layer that is made of a magneto-optic material and includes a plurality of pixels in each of which a magnetization direction is independently set and each of which has a function of causing a rotation of a polarization direction of incident light depending on the magnetization direction by a magneto-optic effect; a plurality of first conductor layers and a plurality of second conductor layers arranged to intersect with each other at positions corresponding to the individual pixels, through which currents for generating magnetic fields to set the magnetization directions in the individual pixels are passed; and a plurality of dielectric layers for enhancing the function of the pixels. A polarization direction of light incident on the spatial light modulator is rotated depending on the magnetization direction of each pixel.

The invention discloses a multiferroic liquid and a preparation method of the multiferroic liquid. The multiferroic liquid of the invention is obtained via the following steps: uniformly mixing a base fluid and a surface active agent as a mixed liquid; then adding ferroelectric nano-particles and magnetic nano-particles in the mixed liquid, shaking the mixture and putting the mixture in a sealed container, and putting the container in a shaking table to shake for more than half an hour to make nano-particles evenly dispersed in the mixed liquid, thereby obtaining a stable suspension liquid, namely the multiferroic liquid. The multiferroic liquid of the invention not only has magnetism and ferroelectricity, but also has fluidity, and is very sensitive to a magnetic field and an electric field. Compared with solid ferroelectric material, the multiferroic liquid of the invention has smaller coercive force, and the particles are easy to rotate under the electric field or the magnetic field. The multiferroic liquid of the invention also has a magneto-optic effect and a refraction effect, which are not possessed by the solid multiferroic material. The invention presents the multiferroic liquid and the preparation method of the multiferroic liquid for the first time so as to develop a new direction for researching the multiferroic material.

An all-fiber isolator as an optical isolator comprises: an optical fiber acting as an optical light guide for propagating incident light; and a Faraday rotator for rotating by 45° a plane of polarization polarized by the polarizer. The all-fiber isolator exhibits a magneto-optic effect enough to be used as an optical isolator at a visible light wavelength by including quantum dots in a core layer and / or an internal cladding layer of the optical fiber.

The invention discloses a measuring method and a measuring device of non-contact electrostatic spraying charge-to-mass ratios, and the measuring method and the measuring device are particularly suitable for calculation of charge-to-mass ratios of charged fogdrops in induction charging and corona charging. The measuring device comprises a laser transmitter (1), an electrostatic sprayer (4), a polarizer (2), a reflector (3), a reflector (3'), a magneto-optical element (6), an analyzer (7), a composite polarized light prism (8), an optical-electrical converter (9), a differential amplifier (10), wires (11) and an oscilloscope (12), wherein the light emitted by the generating laser (1) is a sheet light source. The diameter of the magneto-optical element is D, the distance between the electrostatic sprayer (4) and the magneto-optical element (6) is H, the mist spraying angle of the electrostatic sprayer is theta, and D, H and theta meet the relation that D=2H*tan(theta / 2). Current values of all fogdrops on a charged fogdrop group section can be calculated without contact by the utilization of the Faraday magneto-optical effect and the Ampere circuital theorem through the measuring device, then the current values are divided by mass flow rates of a charged foglet group, and the charge-to-mass ratios can be calculated.

The invention relates to the laser field, in particular to an intracavity frequency doubling laser. The invention includes that a modulator which can adjust fundamental wave light loss in high speed and small amplitude, such as a modulator made by adopting electro optical effect, magneto optic effect, piezoelectric effect or etalon effect, is added into the intracavity frequency doubling laser ofa continuous pump. The characteristic that intracavity frequency doubling laser output power is highly sensitive to intracavity fundamental wave light loss is utilized to realize high speed modulationof frequency doubling laser output power. The invention is especially applicable to high speed modulation of various laser sources in laser display. The invention utilizes new modulation theory and the characteristic that intracavity frequency doubling laser output power is highly sensitive to intracavity fundamental wave light loss to realize high speed modulation of frequency doubling laser output power. The defects of the prior art that modulation range is limited and structure is relatively complex are overcome, and wide frequency range regulation from low frequency to high frequency of the intracavity frequency doubling output light can be realized simply and conveniently.

The invention discloses an optical voltage transformer comprising a voltage-current converter, an optical low-current sensor, and a protection gap. The voltage-current converter is implemented by a high-voltage capacitor and converts primary high voltage into low current. The optical low-current sensor is implemented by a magneto-optic glass optical current transformer and is formed by a magneto-optic glass primary sensor, a transmission optical cable, and an acquisition unit. The magneto-optic glass primary sensor is a magneto-optic glass sensing probe disposed in a solenoid and induces the low current output by the voltage-current converter by means of a Faraday magneto-optic effect. The transmission optical cable is connected with the magneto-optic glass primary sensor and the acquisition unit. The acquisition unit is arranged in a master control chamber or an outdoor cabinet, demodulates a low-current signal induced by a magneto-optic glass optical current transformer optical path system, and outputs a digital signal, indicative of primary voltage, to be used by a relay protection device and a metering device.

A target material for magneto-optical record (optical disk or magneto-optical disk) is based on the principle that the light- or medium-weight rare-earth elements have high saturation magnetization intensity, magnetocrystalline anisotropy and magneto-optical effect. It is prepared through magnetic suspension smelting of FeCo alloy as basic target alloy, linearly cutting the pure terbium and light-weight rare-earth element to obtain sectorial or circular sheets, symmetrically inlaying them on said basic target. Its advantages are high uniformity, low cost and high efficiency.

The invention discloses a welding seam texture tissue nondestructive testing system. The welding seam texture nondestructive testing system comprises an alternating magnetic field generator and a magneto-optic sensor, wherein the alternating magnetic field generator is used for carrying out alternating excitation on a to-be-tested weldment, and the to-be-tested weldment produces an alternating magnetic field by virtue of the alternating magnetic field generator; the magneto-optic sensor is used for transmitting a polarized light to the to-be-tested weldment, can receive the polarized light reflected by the to-be-tested weldment and carries out imaging; and an imaging signal generated by the magneto-optic sensor is sent into a processor to be analyzed and processed. The welding seam texture tissue nondestructive testing system disclosed by the invention is applied to Faraday magneto-optical effect, when one polarized light passes through a magneto-optical thin film medium with magnetorotation property, a vibration plane of light vibration can rotate for a specific angle after the light passes through the medium due to existence of an external magnetic field, and the processor determines which part goes wrong by virtue of a deflection angle. The to-be-tested weldment does not need to be damaged in a testing process, nondestructive testing is realized, the alternating magnetic field can be used for measuring texture tissue characteristic of workpieces with high magnetic conductivity and low magnetic conductivity respectively, and an application range is wider.

A delay interferometer includes first and second optical paths into which incident signal light is split, a first converter including one or more conversion parts to convert the signal light on the first optical path into circularly polarized light and to convert the circularly polarized light into linearly polarized signal light, a phase adjuster to shift an optical phase of the circularly polarized light through a magneto-optic effect, and a second converter to convert a polarization state of the signal light on the second optical path into substantially the same polarization state as a polarization state of the linearly polarized signal light.

The invention provides a primary current signal simulator for an optical current transformer based on a faraday effect. The optical current transformer comprises a light source, a polarizer, a deflector of magneto-optical material, a polarization analyzer, a photoelectric conversion module, an electrical signal amplification and processing module, an analog / digital conversion module and a micro control unit (MCU) operation and processing module, wherein the light source is a modulated light source capable of replacing a constant power light source in the optical current transformer based on the faraday effect, so as to ensure that the changes of optical power output by the polarization analyzer when the deflector of the magneto-optical material is not positioned in a magnetic field are the same as the changes of optical power output when the deflector of the magneto-optical material is positioned in the magnetic field.