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38 results about "Atomic vapor" patented technology

Electric field measuring device for continuously tunable microwave frequency based on Rydberg atoms

The invention provides an electric field measuring device for continuously tunable microwave frequency based on Rydberg atoms. The electric field measuring device comprises a reflecting mirror, an atom steam pool, a first electrode plate, a second electrode plate, a dichroscope, a photoelectric detector and a data receiving module, the detection laser passing through the reflector and the coupling laser passing through the dichroscope oppositely hit into the atom steam pool to coincide, and a transmitted optical signal enters the photoelectric detector after hit into the atom steam pool; the photoelectric detector is electrically connected with the data receiving module; the first electrode plate and the second electrode plate are externally arranged above and below the atomic steam pool respectively; the first electrode plate and the second electrode plate are used for applying an alternating current electric field acting on the atomic steam pool, and different AC Stark frequency shifts are generated by controlling the electric field intensity of the alternating current electric field, so that high-sensitivity measurement of the continuous tunable microwave frequency electric field is realized. According to the invention, high-sensitivity measurement of the continuous tunable microwave frequency electric field can be realized, and the accuracy of a measurement result is ensured.
Owner:SICHUAN JIUZHOU ELECTRIC GROUP CO LTD

Multimodal fusion detection apparatus and method based on optical pumping and photoacoustic imaging

A multimodal fusion detection apparatus and method based on optical pumping and photoacoustic imaging are provided, relating to the field of fusion detection technology. In the apparatus, the atomic vapor cell detection path and the first laser irradiation path are both directed toward a target region and at least partially overlap. In this way, the detection paths of optical pumping and photoacoustic imaging are at least partially coincident, ensuring that electrophysiological signals and blood oxygen signals originate from the same tissue region and avoiding the spacing constraints of conventional sensors. Thus, the detection path of the atomic vapor cell can be used for both magnetic field detection and photoacoustic detection, enabling simultaneous acquisition of magnetic and photoacoustic signals at a single detection point, achieving hardware reuse for multimodal fusion detection at the same location and time, reducing device size, and minimizing crosstalk among multimodal sensors.
Owner:WESTLAKE UNIV

Self-locked rydberg atom electric field sensor

A system for automatically locking a control laser in a Rydberg atomic sensor may comprise an atomic vapor cell, a probe laser configured to excite the atoms in the atomic vapor cell to an intermediate energy state, and a control laser configured to excite the one or more atoms in the atomic vapor cell from the intermediate energy state to a higher energy state. The light generated by the control laser may be dithered at a pre-determined frequency. The system further comprises a photodiode configured to convert light received from the vapor cell into an electrical signal, a lock-in amplifier configured to generate an error signal based on the electrical signal received from the photo diode and a received reference oscillation frequency, and a servo configured to receive the generated error signal from the lock-in amplifier and adjust a frequency of the control laser based on the received error signal.
Owner:THE MITRE CORPORATION

Thermal package for atomic devices

Various embodiments include a thermally packaged atomic device. The thermally packaged atomic device includes an atomic vapor unit, a heater, and a housing. The atomic vapor unit is located within the housing. The heater heats the atomic vapor unit. The housing is filled with a gas selected to have a thermal conductivity less than that of air. The gas having a thermal conductivity less than that of air may include xenon or krypton. The enclosure surrounds the atomic vapor unit with a gas.
Owner:FIELD LANE CO LTD

Doppler-free two-photon optical atomic clock

Optical frequency reference apparatus (10) comprising - an atomic vapor cell (1), containing a vapor of reference atoms, said atomic vapor cell (1) comprising a first end (41) having a first window (4) and a second end (61), - a laser source (11) for generating a laser probe beam (3) adapted to excite a two-photon optical transition of said reference atoms, - an optical detector (14), adapted to detect a fluorescence signal emitted by said reference atoms, and - at least one reflective element (5, 15) wherein the laser source (11), the atomic vapor cell (1) and the at least one reflective element (5, 15) are configured such that, in operation, the probe beam (3) enters the atomic vapor cell (1) through said first window (4) at said first end (41) and crosses said vapor of reference atoms until said second end (61) through a defined optical path in a first forward direction (3a), the probe beam (3) is reflected backwards by said at least one reflective element (5, 15) and crosses said vapor of reference atoms a second time through the same defined optical path, in a second direction (3b) opposite to the first forward direction (3a), characterized in that the optical frequency reference apparatus (10) further comprises means (7, 9) for absorbing the reflected laser probe beam (3) exiting from the atomic vapor cell (1) according to the second direction (3b).
Owner:ROLEX SA

Low-power source of squeezed light

A degenerate four-wave mixing (DFWM) squeezed light apparatus includes one or more pump beams, a probe beam, a vapor cell, a repump beam, and a detector. The one or more pump beams includes an input power of no greater than about 150 mW. The vapor cell includes an atomic vapor configured to interact with overlapped pump and probe beams to generate an amplified probe beam and a conjugate beam. The repump beam is configured to optically pump the atomic vapor to a ground state and decrease atomic decoherence of the atomic vapor. The detector is configured to measure squeezing due to quantum correlations between the amplified probe beam and the conjugate beam. The one or more pump beams, the probe beam, and the repump beam are configured to generate two-mode squeezed light by DFWM with squeezing of at least 3 dB below shot noise.
Owner:THE MITRE CORPORATION

Low-noise atom modulation spectrum detection system and method based on saturated fluorescence detection

The low-noise atom modulation spectrum detection system comprises a signal generator, sine wave signals generated by the signal generator are divided into two paths, one path is output to a laser device, and laser with modulation information is modulated in a current control mode; and the other path provides a reference signal for demodulation of the lock-in amplifier, the output laser is divided into pump light and probe light to ensure generation of saturated fluorescence in the rubidium atom steam chamber, then a low-noise silicon photoelectric detector is used for detecting a saturated fluorescence signal, and the lock-in amplifier demodulates and outputs the modulated saturated fluorescence signal. And meanwhile, a detection path of the saturated absorption spectrum is reserved, so that comparison with a modulated saturated fluorescence spectrum signal is facilitated. According to the invention, the requirement on the size of the atom steam chamber is obviously reduced, and the method is suitable for the application scenes of the Suppler spectrum, such as high-sensitivity, low-noise, anti-interference and miniaturized laser frequency stabilization and atom hyperfine structure detection.
Owner:HONG KONG UNIV OF SCI & TECH (GUANGZHOU)

Atomic vapor chamber and configuration of atomic optical clock implementing said atomic vapor chamber

A system (30) for controlling, regulating or authenticating a timer comprises means (31) for measuring the frequency signal and / or rate of one or more timers based on a time reference provided by an optical atomic clock (10) comprising an atomic vapor chamber (1), the atomic vapor chamber (1) comprises a hermetically sealed enclosure (8) defining a volume containing a vapor of a reference atom (2), the hermetically sealed enclosure (8) comprising an optical inlet (3) allowing transmission of a probe beam adapted to excite an optical transition of the reference atom (2) and an optical outlet (4) allowing transmission of a fluorescence signal from the reference atom (2), the hermetically sealed housing (8) further comprises a wall (5) through which the fluorescent signal can penetrate, said wall (5) being coated on its outer side with a coating (6) which is reflective to the fluorescent signal.
Owner:ROLEX SA

Atom-based closed-loop control for electromagnetic radiation measurement, communications, and information processing

A method for atom-based closed-loop control includes exciting atoms of a gas into one or more Rydberg states, applying one or more signal processing functions to the one or more Rydberg states, and regulating a characteristic of the applied one or more signal processing functions based on, at least in part, a response of the one or more Rydberg states to the one or more signal processing functions. A system for internal quantum-state-space interferometry includes an atomic receiver, an interferometric pathway, and a detector. The interferometer includes an atomic vapor with first atomic states and second atomic states. The interferometric pathway from RF phases between the first and second atomic states is closed by a quantum-state-space. The detector is configured to detect a readout of an interferometric signal. Embodiments include atom-based automatic level control, baseband processors, phase-locked loops, voltage transducers, raster RF imagers and waveform analyzers.
Owner:RYDBERG TECHNOLOGIES INC

Atomic sensor with self-aligned components

ActiveUS12717282B2Mechanical engineeringAtomic vapor
Techniques are provided self-aligning components of an atomic sensor including a first cover, a second cover, a structure-cell including a structure and a cell, containing a vapor of atoms, in the structure. Atomic sensor components are aligned in a cover in which they are form fitted into a recess or mounted on a surface of a pedestal. Each cover is aligned with the structure-cell or component(s) therein using guide holes in each of the cover and the structure-cell into each of which an alignment pin is inserted. Due to such alignments, each component is self-aligned with respect another component or to a region of the structure-cell, e.g., the cell or an atomic vapor in the cell.
Owner:HONEYWELL INTERNATIONAL INC

Optical atomic clock system

PendingCN121956474AImprove stabilityEliminate dead timeApparatus using atomic clocksComputational physicsAtomic vapor
The present invention provides an optical atomic clock system comprising: an optical pulse generation component adapted to generate a clock interrogation optical pulse; the atomic furnace is used for generating atomic steam; each subsystem is suitable for capturing and preliminarily cooling atoms in the received atom steam to obtain a cold atomic group, and is used for trapping the atoms in the cold atomic group; the subsystem is constructed to allow clock polling pulse light to enter, so that atoms in a ground state interfere with each other under the action of two clock polling light pulses; the processing component is used for obtaining an error signal of the subsystem according to the interference result in any subsystem; a timing controller configured to: cause atoms within the at least one subsystem to be in an illumination phase of the clock interrogation light pulse or in a free evolutionary phase between two illumination of the clock interrogation light pulse; the frequency of the clock interrogation light pulse is corrected according to the respective error signals of the plurality of subsystems.
Owner:HEFEI NATIONAL LABORATORY +1

Heating device

The application relates to the technical field of cold atoms, in particular to a heating device for generating an atomic vapor flow. The device comprises a first furnace body and a second furnace body, the inner cavity of the first furnace body is communicated with the inner cavity of the second furnace body through a communication port, the second furnace body is provided with a gas outlet communicated with the inner cavity of the second furnace body, the outer wall of the first furnace body is provided with a heat source layer for heating the first furnace body, the second furnace body at least comprises a first temperature drop section and a second temperature drop section arranged in sequence along the direction from the communication port to the gas outlet, the thermal resistance value of the first temperature drop section and the thermal resistance value of the second temperature drop section make the temperature of the second furnace body connected with the first furnace body change according to a preset temperature drop curve, the abscissa of the temperature drop curve is the axial distance of the second furnace body, and the ordinate is the temperature value. The heating device is designed by segmenting the thermal resistance value of the second furnace body, so that the second furnace body can realize temperature drop according to the preset temperature drop curve, stable temperature control can be realized by only one heat source, and the structure and control are relatively simple.
Owner:TIANFU XINGLONG LAKE LAB

Systems and methods for performing quantum telecommunications using a bichromatic entanglement source

Systems and methods for generating an entangled pair of bichromatic photons are described. The system includes an atomic vapor cell containing atoms of an atomic species located within beam paths of a first and second laser beam. The first and second laser beams are tuned to first and second wavelengths that are resonant with first and second atomic transitions of the atomic species such that the first and second laser beams cause a four-wave mixing process within the atomic vapor cell. As a result of the four-wave mixing process, entangled photon pairs having a third and fourth wavelength are generated and output from the atomic vapor cell. The first and second wavelengths may be selected to create electromagnetically-induced transparency (EIT) within the atomic vapor cell, the EIT creating a transparent medium within the atomic vapor cell at the third wavelength, improving spectral brightness and / or photon linewidths.
Owner:QUNNECT INC

Optical pumping-based multimodal fusion detection apparatus

An optical pumping-based multimodal fusion detection apparatus is provided, relating to the field of brain-computer interfaces. The system includes a laser generation module, laser path control module, atomic vapor cell, photodetection module, ultrasonic detection module, and data processing module. The photodetection module, ultrasonic detection module, and data processing module function as a detection module. The detection module collects the laser intensity and polarization variation signals of the first laser after passing through the atomic vapor cell to output local magnetic field variations in the brain caused by neural discharges. It also collects ultrasonic signals corresponding to an interaction of the second pulsed laser with the measured part to output the subject's blood oxygen signal.
Owner:WESTLAKE UNIV

Communication method and related device

A communication method and a related device are applied to the field of communication. In the method, a first device receives a first microwave signal to be detected; the first device sends a first laser signal to a first atomic steam cavity to obtain first signal intensity, the first signal intensity is the signal intensity of the first laser signal penetrating through the first atomic steam cavity, the frequency of the first laser signal changes periodically, and the transmissivity of the first atomic steam cavity is related to the first microwave signal; the first device determines a first attribute of the first microwave signal according to the first signal intensity and the frequency of the first laser signal, and the first attribute comprises the signal intensity or the signal frequency so as to increase the signal bandwidth of microwave signal detection.
Owner:HUAWEI TECH CO LTD

Atom-based closed-loop control for electromagnetic radiation measurement, communication, and information processing

To improve EM sensing, detection, measurement, imaging, reception, communication, and source generation by extending capabilities beyond those achievable with conventional sensor technologies and using atom-based quantum sensor technologies.SOLUTION: A method for atom-based closed-loop control includes exciting atoms of a gas into one or more Rydberg states, applying one or more signal processing functions to the one or more Rydberg states, and adjusting characteristics of the applied one or more signal processing functions based at least in part on a response of the one or more Rydberg states to the one or more signal processing functions. A system for internal quantum state space interferometry includes an atomic receiver, an interference path, and a detector. The interferometer includes an atomic vapor having a first atomic state and a second atomic state. The interference path from an RF phase between the first and second atomic states is closed by a quantum state space. The detector is configured to detect a readout of an interference signal.SELECTED DRAWING: Figure 1
Owner:RYDBERG TECHNOLOGIES INC

Microwave electric field measurement probe device and method of use

The application discloses a microwave electric field measuring probe device and a use method thereof. The device comprises an atomic vapor chamber, a double-wavelength spectrometer prism connected to the end of the atomic vapor chamber, an input coupling light fiber collimation assembly and an output signal light fiber collimation assembly connected to the end of the double-wavelength spectrometer prism away from the atomic vapor chamber, an input probe light fiber assembly connected to the atomic vapor chamber, the input probe light fiber assembly connected to the end of the atomic vapor chamber away from the double-wavelength spectrometer prism, the input probe light fiber assembly, the output signal light fiber collimation assembly and the atomic vapor chamber arranged on the same axial line, probe light capable of passing through the double-wavelength spectrometer prism into the output signal light fiber collimation assembly, and coupling light entering the atomic vapor chamber capable of coinciding with the probe light capable of passing through the double-wavelength spectrometer prism in the atomic vapor chamber. The purpose of improving light collection efficiency and use flexibility is achieved.
Owner:BEIJING INST OF RADIO METROLOGY & MEASUREMENT

Self-locked Rydberg atom electric field sensor

A system for automatically locking a control laser in a Rydberg atomic sensor may comprise an atomic vapor cell, a probe laser configured to excite the atoms in the atomic vapor cell to an intermediate energy state, and a control laser configured to excite the one or more atoms in the atomic vapor cell from the intermediate energy state to a higher energy state. The light generated by the control laser may be dithered at a pre-determined frequency. The system further comprises a photodiode configured to convert light received from the vapor cell into an electrical signal, a lock-in amplifier configured to generate an error signal based on the electrical signal received from the photo diode and a received reference oscillation frequency, and a servo configured to receive the generated error signal from the lock-in amplifier and adjust a frequency of the control laser based on the received error signal.
Owner:THE MITRE CORPORATION

High-bandwidth photonic memory with a warm atomic vapor

Techniques for facilitation the storage and retrieval of the qubits in a hot atomic vapor system are described herein. The techniques comprising, transmitting a first control pulse having a bandwidth that is based on a bandwidth of the optical qubit to modify transmission properties of the atomic vapor system: receiving the optical qubit at the atomic vapor system; transmitting a second control pulse having properties based on a target bandwidth for a retrieved optical qubit to modify transmission properties of the atomic vapor system; and isolating the retrieved optical qubit from the control laser.
Owner:QUNNECT INC

A method for simultaneously improving sensitivity and absolute accuracy of CPT magnetometer

The application discloses a method for simultaneously improving sensitivity and absolute accuracy of a CPT magnetometer, and the method adjusts the intensity of pumping radiation through a feedback loop to keep the spontaneous fluorescence of atomic vapor at a constant level, thereby improving the contrast of CPT resonance. In the experiment, a double-frequency laser field is adopted, the 795nm laser is modulated and divided into two beams of orthogonal polarized light to excite two hyperfine level states of 87Rb atoms. The fluorescence signal is detected and kept at a fixed intensity through PID feedback control. The common-mode noise and other interference factors are eliminated through differential processing of two groups of CPT signals, so that the Larmor frequency under a simulated 5000nT magnetic field is accurately determined, and the Larmor frequency is about 350kHz. The application proposes a method for improving the sensitivity and accuracy of the magnetometer through a fluorescence feedback loop and differential detection, and simultaneously solves the frequency offset problem caused by common-mode noise and nonlinear effects in the traditional method, and is suitable for high-precision magnetic field measurement.
Owner:BEIHANG UNIV +1

Communication method and related apparatus

A communication method and a related apparatus, which are applied to the field of communications. In the method, a first apparatus receives a first microwave signal to be measured; the first apparatus sends a first laser signal to a first atomic vapor cavity, so as to obtain a first signal strength, wherein the first signal strength is the signal strength of the first laser signal after the first laser signal passes through the first atomic vapor cavity, the frequency of the first laser signal changes periodically, and the transmittance of the first atomic vapor cavity is related to said first microwave signal; and the first apparatus determines a first attribute of said first microwave signal on the basis of the first signal strength and the frequency of said first laser signal, wherein the first attribute includes a signal strength or a signal frequency, so as to increase signal bandwidths for microwave signal measurement.
Owner:HUAWEI TECH CO LTD

Ultra-high brightness narrow-linewidth photon source for generating entangled photon pairs or heralding single photons

A system and method are provided for generating entangled photon pairs containing two photons having different wavelengths. The technique involves pumping an atomic vapor of an alkali species using a pump laser and a coupled laser configured to drive a spontaneous four-wave mixing process within the atomic vapor. The pump laser and the coupled laser are detuned with respect to atomic transitions of the alkali species, thereby increasing the brightness of the entangled photon pair source.
Owner:QUNNECT INC

Atomic magnetometer

A method of measuring an external magnetic field using an atomic magnetometer comprises: using a polarized pump beam 1 to spin-polarise the atomic vapour; magnetising the polarized atomic vapour by a
Owner:BLOOMSBURY ATOMICS LTD

Atomic vapor cell and atomic optical clock incorporating atomic vapor cell

What is needed is an optical scheme that provides high collection efficiency while reducing the effects of the vapor cell heating the temperature-sensitive photodetector.SOLUTION: The system for controlling, adjusting or certifying the timepiece includes a means for measuring a frequency signal and / or a rate of the timepiece or several timepieces based on a time reference provided by an optical electronic timepiece 10. Wherein the optical electronic watch comprises an atomic vapor cell 1, the atomic vapor cell comprising a sealed enclosure defining a volume containing a reference atomic vapor, the sealed enclosure comprising an optical inlet 3 allowing transmission of a probe beam adapted to excite an optical transition of the reference atoms and an optical outlet 4 allowing transmission of a fluorescence signal from the reference atoms, the sealed enclosure further comprising a wall 5 transparent to the fluorescence signal and coated on its outside with a coating reflecting the fluorescence signal.SELECTED DRAWING: Figure 5
Owner:ROLEX SA

Atom-based closed-loop control for electromagnetic radiation measurement, communications, and information processing

PendingUS20260186040A1Waveform analysisLoop control
A method for atom-based closed-loop control includes exciting atoms of a gas into one or more Rydberg states, applying one or more signal processing functions to the one or more Rydberg states, and regulating a characteristic of the applied one or more signal processing functions based on, at least in part, a response of the one or more Rydberg states to the one or more signal processing functions. A system for internal quantum-state-space interferometry includes an atomic receiver, an interferometric pathway, and a detector. The interferometer includes an atomic vapor with first atomic states and second atomic states. The interferometric pathway from RF phases between the first and second atomic states is closed by a quantum-state-space. The detector is configured to detect a readout of an interferometric signal. Embodiments include atom-based automatic level control, baseband processors, phase-locked loops, voltage transducers, raster RF imagers and waveform analyzers.
Owner:RYDBERG TECHNOLOGIES INC

Chip-scale atomic beam generating systems

An exemplary embodiment of the present disclosure provides a chip-scale atomic beam system comprising an atomic vapor source, a plurality of channels, and a propagation chamber. The atomic vapor source chamber can comprise an atomic vapor source configured to emit an atomic vapor. The plurality of channels can have first ends and second ends. The first ends can be in fluid communication with the atomic vapor source chamber. The plurality of channels can be configured to collimate the atomic vapor as it moves through the plurality of channels from the first ends to the second ends. The propagation chamber can be in fluid communication with the second ends of the plurality of channels. The propagation chamber can have an internal pressure less than an internal pressure of the atomic vapor source chamber to enable the collimated atomic vapor to propagate through the propagation chamber.
Owner:GEORGIA TECH RES CORP +1

Atomic sensor with self-aligned components

Techniques are provided self-aligning components of an atomic sensor including a first cover, a second cover, a structure-cell including a structure and a cell, containing a vapor of atoms, in the structure. Atomic sensor components are aligned in a cover in which they are form fitted into a recess or mounted on a surface of a pedestal. Each cover is aligned with the structure-cell or component(s) therein using guide holes in each of the cover and the structure-cell into each of which an alignment pin is inserted. Due to such alignments, each component is self-aligned with respect another component or to a region of the structure-cell, e.g., the cell or an atomic vapor in the cell.
Owner:HONEYWELL INTERNATIONAL INC

Magneto-optically controlled atomic localization under induced generated coherence

PendingUS20250357938A1Quantum computersPulse automatic controlAtomic systemPolarizer
A method, for atomic localization in a four-level atomic system. The method includes generating a magnetic field and a linearly polarized weak probe field. The magnetic field and the linearly polarized weak probe field are generated by a polarizer. The method also includes generating a strong control field. The method includes applying the magnetic field, the linearly polarized weak probe, and the strong control field to atomic vapors. The method includes generating an SGC effect to the atomic vapors based on an interference created by applying the magnetic field, the linearly polarized weak probe, and the strong control laser field to atomic vapors. The method includes determining atom locations based on generating the SGC effect; and also generating an electronic graph showing the atom locations.
Owner:ABU DHABI UNIVERSITY

Chip-scale atomic diffraction optical element and preparation method thereof

The invention relates to the technical field of micro-nano optics and atomic devices, in particular to a chip-level atomic diffraction optical element and a preparation method thereof. Comprising an SOI wafer, a getter pill chamber, an alkali metal release pill chamber, a diffraction grating, upper cover plate glass and lower cover plate glass, the getter pill chamber, the alkali metal release pill chamber and the diffraction grating are respectively arranged in the getter pill area, the alkali metal release pill area and the diffraction grating area, the getter pill chamber and the alkali metal release pill chamber penetrate through the SOI wafer, the getter pill chamber is communicated with the alkali metal release pill chamber, the alkali metal release pill chamber is communicated with the diffraction microstructure, and the diffraction microstructure is communicated with the diffraction microstructure. Getter pills are sealed in the getter pill chamber, and alkali metal release pills are sealed in the alkali metal release pill chamber. According to the original, atom steam is sealed in an unprocessed diffraction structure, a unique interference spectrum is generated, and wide-bandwidth and high-precision laser frequency offset locking under the condition of no magnetic field is realized.
Owner:CENT CHINA OPTOELECTRONICS TECH RES INST (CHINA STATE SHIPBUILDING CORP 717TH RES INST)

High-sealing miniature atomic gas chamber for quantum sensing and manufacturing method of high-sealing miniature atomic gas chamber

The invention discloses a high-sealing miniature atomic gas chamber for quantum sensing, which sequentially comprises a first glass substrate, a second glass substrate and a third glass substrate from top to bottom, the second glass substrate is internally provided with an atmosphere chamber cavity for accommodating buffer gas and atom steam, a small rubidium source cavity for placing a solid rubidium source and a micro-pore channel for connecting the large cavity and the small cavity to release rubidium atoms; the light-passing windows of the first glass substrate and the third glass substrate are respectively aligned with the atmosphere chamber cavity to form a double-end optical path; the invention further discloses a manufacturing method. According to the invention, a three-layer glass structure is adopted, femtosecond laser cutting and welding are carried out, local gold plating is carried out to enhance absorption, and the high-sealing micro atomic gas chamber is suitable for high-precision quantum sensing equipment such as chip-level atomic clocks, atomic magnetometers and quantum gyroscopes.
Owner:WUHAN HUAZHONG TIANWEI MEASUREMENT & CONTROL CO LTD