59 results about "Quartz tuning fork" patented technology

The invention relates to the technical field of gas sensing detection, and discloses a gas detection method and system based on a quartz tuning fork enhanced photoacoustic spectrum. The method comprises the following steps: constructing a standardized continuous tuning fork signal data stream; dynamically segmenting the data stream based on the gas concentration interval, and extracting time domain and frequency domain features in parallel in each segment to form an initial feature vector; dynamically adjusting an anomaly judgment threshold according to the jump amplitude of the adjacent segment feature vectors, and scanning and screening out an effective analysis interval of a stable concentration state according to the anomaly judgment threshold; performing cross-domain coupling compensation on the feature vectors in the effective interval to generate enhanced feature vectors; and finally, performing reverse traceability reasoning through a gas leakage propagation model based on the enhanced feature vector, and outputting a leakage source position identifier. The device can adapt to a dynamically changing concentration field, and the reliability and traceability positioning capability of gas detection in a complex environment are improved.

The invention provides a quartz enhanced photoacoustic spectrometry detection system environment gas interference correction method which can be applied to the technical field of photoacoustic spectrometry gas detection. The method comprises the following steps: analyzing vibration-translation relaxation time and infrared absorption peak intensity of each gas to be detected; the to-be-detected gas with the vibration-translation relaxation time exceeding the time threshold value and the absorption peak intensity larger than the intensity threshold value is selected as comparison gas; dividing the laser of the comparison gas into a first laser beam and a second laser beam according to a preset proportion; using the first laser beam to excite a sound wave signal and detecting by a quartz tuning fork to generate a tuning fork electric signal; the second laser beam is enhanced and absorbed by a multi-reflection absorption cell and then is detected by a photoelectric detector to generate a light intensity electric signal; establishing a neural network model taking the tuning fork electric signal, the light intensity electric signal and the environment gas component vector as input and taking the to-be-detected gas concentration vector as output; and correcting the concentration of the to-be-detected gas under the interference of the environmental gas in real time through the trained neural network model.

The invention provides a resonant bionic cilia vector hydrophone based on a quartz tuning fork and an underwater acoustic system, and relates to the technical field of micro-mechanical electronics. A vibration detection mechanism in the hydrophone comprises two quartz tuning forks located in a first axial direction and two quartz tuning forks located in a second axial direction, the first axial direction is perpendicular to the second axial direction, one end of each quartz tuning fork is fixed, and the other end of each quartz tuning fork is connected with a vibration acquisition mechanism; and the vibration acquisition mechanism is connected with the quartz tuning forks and is used for driving the two quartz tuning forks in the same axial direction to generate symmetrical frequency deviation under the action of sound waves. According to the embodiment of the invention, the excellent frequency stability and strain sensitivity of the double-end fixed tuning fork can be utilized to realize efficient conversion of sound signals and generation of corresponding electric signals, digital signal output can be conveniently realized, high-sensitivity detection of the sound signals can be effectively realized, the influence of common-mode signals can be inhibited, the anti-interference performance is good, and the detection precision is high. And the underwater sound detection effect is greatly improved.

The application discloses a kind of chirp modulation photo-thermal-optical spectrum resonance frequency and concentration synchronous measurement method and system, belong to photo-thermal-optical spectrum field, comprising: S1, generating chirp modulation signal driving laser, produces modulated laser beam;S2, the modulated laser beam is inducted after passing through gas to the surface of quartz tuning fork excitation photo-thermal-optical signal demodulation obtains first harmonic signal;S3, using lorentz line function fitting the first harmonic signal;S4, according to fitting result, the center resonance frequency position of quartz tuning fork is calculated;S5, whether the center resonance frequency position of the quartz tuning fork is located in the center of first harmonic signal;If not, adjust chirp modulation signal initial frequency repeats S1-S5, until the center resonance frequency position of quartz tuning fork is located in the center of first harmonic signal;S6, according to fitting result, response coefficient is calculated, and inversion obtains gas concentration information.The application can realize high-precision measurement of gas concentration and real-time correction of resonance frequency.

The application relates to the technical field of accelerometers, and provides a quartz vibrating beam accelerometer sensitive structure, which comprises a quartz flexible beam arranged at one end of a rigid beam, a quartz mass pendulum arranged at the other end of the quartz flexible beam, and a quartz tuning fork vibrating beam structure connected with the rigid beam at one end and connected with the quartz mass pendulum at the other end. The quartz vibrating beam accelerometer sensitive structure provided by the application is provided with the quartz flexible beam, the quartz mass pendulum and the quartz tuning fork vibrating beam structure, all of which are made of quartz crystal materials, so that the matching of the material thermal expansion coefficient can be improved, and the temperature drift problem caused by the mismatching of the material thermal expansion coefficient is solved.

The application discloses a quartz enhanced photoacoustic spectroscopy detection method and system using optical feedback, and belongs to the technical field of optical feedback. The method comprises the following steps: controlling the phase of optical feedback according to a laser based on a first reflector and a second reflector; matching the cavity film size of a laser and an F-P cavity; establishing stable optical feedback of the laser according to the phase of optical feedback; transmitting the laser passing through a polarizer to a fourth reflector, refracting the laser into the F-P cavity matched with the laser through a CaF2 window mirror, and passing the laser passing through the F-P cavity through the middle of the first resonant tube, the second resonant tube and the prong of the quartz tuning fork, so as to generate a photoacoustic signal based on the stable optical feedback, enhance the photoacoustic signal based on the first resonant tube and the second resonant tube, and detect the spectrum based on the enhanced photoacoustic signal. The application improves the anti-interference of detection.

This invention provides a quartz gyroscope circuit, including a closed-loop drive circuit. The closed-loop drive circuit includes a drive interdigitator, a drive terminal circuit, and a controller. The drive terminal circuit converts the drive response charge signal generated by the drive interdigitator into a drive response voltage signal and transmits the drive response voltage signal to the controller. The controller generates an original digital reference signal, adjusts the frequency and amplitude of the original digital reference signal based on the drive response voltage signal to generate a drive voltage signal, and transmits the drive voltage signal to the drive terminal circuit. The drive terminal circuit amplifies the drive voltage signal and applies the amplified drive voltage signal to the drive interdigitator so that the oscillation frequency of the drive interdigitator is at the resonant frequency of the quartz tuning fork, and the oscillation amplitude of the drive interdigitator is within a preset amplitude range. This invention addresses the shortcomings of existing analog quartz gyroscopes, where the oscillation frequency cannot operate at the resonant frequency and the oscillation amplitude is unstable.

The application discloses a photoacoustic spectrum sound detector and a gas detection device, which comprises a first Helmholtz resonant cavity, a quartz tuning fork and a second Helmholtz resonant cavity. The two Helmholtz resonant cavities are coaxially connected by a cylindrical barrel and a thin tube. When laser is incident from the light transmission window of the first Helmholtz cavity, passes through the gap between the vibrating arms of the quartz tuning fork and is emitted from the window of the second Helmholtz cavity, the two Helmholtz resonant cavities resonate and amplify the sound wave signal excited by the laser beam, so that the sound pressure near the vibrating arms of the quartz tuning fork is enhanced, the environmental noise and the window noise are suppressed, and the signal-to-noise ratio of the quartz tuning fork in detecting the sound wave signal near the vibrating arms is improved. In the application, the Helmholtz cavity can resonate and amplify the sound wave, thereby improving the output signal amplitude. In the measurement process, the Helmholtz cavity can suppress the environmental noise and the window noise, further improve the signal-to-noise ratio and improve the gas detection precision.

The application discloses a Fourier photoacoustic gas detection device and method, and belongs to the technical field of gas detection. In view of the limited anti-interference ability of a sound signal and the low detection sensitivity of an existing Fourier transform photoacoustic spectrum, a Fourier photoacoustic gas detection device is designed. A supercontinuum broadband light source is used as an excitation light source of a photoacoustic effect, the broadband light source is subjected to unified intensity modulation through an intensity modulation assembly and phase modulation through an interferometer assembly. After the broadband interference light emitted through double modulation interacts with gas molecules, wide-spectrum mixed sound waves are generated, a quartz tuning fork sound measurement assembly extracts resonance components and converts the resonance components into electrical signals. The generated electrical signals are sequentially subjected to processing through a signal amplification assembly, a phase-sensitive demodulation assembly and a Fourier transform assembly, and the processed signals are used for component discrimination and concentration inversion of a target gas.

Spectroscopic sensor for characterizing the absorption or determining the concentration of solid materials or liquid samples based on the photoacoustic effect, comprising - a device into which the liquid or solid sample to be analyzed is inserted or placed, - at least one laser in modulation mode to excite the material-specific molecules, - at least one sound transducer for detecting the sound pressure wave, - a device for detecting and processing the photoacoustic signal, characterized in that at least one sound transducer in the form of a quartz tuning fork (QTF) is used, the resonance frequency of which corresponds to the laser modulation frequency, that an acoustic resonator of a certain geometry, which is placed on the sample and has the same resonance frequency as the QTF, is used, that the laser modulation frequency corresponds to the resonance frequency of the resonator, and that the gas which fills the resonator shows as little or no absorption as possible in the wavelength range of the laser.

The invention provides a gas detection method and a gas detection system, and belongs to the technical field of spectral measurement, and the method comprises the following steps: carrying out collimation processing on a laser beam through a collimating lens; the wavelength of the laser beam is matched with the A band of the target gas; after the collimated laser beam penetrates through the gas in the medicine bottle to be detected, focusing the emergent laser beam to a quartz tuning fork by using a focusing lens; the quartz tuning fork converts the received optical signal into an electric signal; the absorption spectrum of the target gas is obtained along with the change of the wavelength of the laser, and then the concentration of the target gas in the medicine bottle to be detected is determined. The intensity of a traditional transmission absorption measurement mechanism is improved through the photoacoustic effect, limitation of medicine bottle refraction and internal shielding on long optical path construction is avoided, the requirements of the system for optical alignment precision and spatial layout are greatly reduced, and miniaturization and engineering applicability of equipment are achieved while high sensitivity is guaranteed.

The application provides a quartz vibrating beam accelerometer with enhanced temperature environment adaptability, wherein a TO package of a sensitive structure is not fixedly installed to an accelerometer shell in a conventional metal connection mode, but is fixed to an inner wall of the shell through a ring-shaped glue body, so that the influence of external environment temperature change can be reduced, and the temperature performance of the accelerometer is improved; a heat insulation baffle is installed between a circuit and a head of the sensitive structure, so that the temperature gradient between double beams of the sensitive structure caused by the start-up temperature rise of the circuit can be effectively reduced, and the start-up time of the accelerometer is reduced.

The application provides a quartz tuning fork resonator and a manufacturing method thereof, which comprises a base, a pair of vibration arms formed on the base, and a counterweight region formed at an end of the vibration arms away from the base, wherein an upper surface of the counterweight region is formed with a metal film layer, a blank gap is left between an edge of the metal film layer and a physical edge of the counterweight region, and the thickness of the metal film layer gradually decreases from a central region to an edge region. The application improves the controllability of film layer distribution by setting the blank gap and the gradient metal film layer with a central thickness and an edge thickness, completely inhibits the metal vapor superposition of the edge and the sidewall of the counterweight region from the structural level, eliminates the local stress concentration, and improves the long-term frequency stability.

The application discloses an integral cavity enhanced LITES gas concentration detection system and a design method thereof, relates to the LITES gas concentration detection technology, and aims to solve the problem that the prior art cannot consider safety, precision and sensitivity simultaneously. In the system, a quartz tuning fork is arranged at a central position of an integral cavity; laser generated by a laser generating device enters a gas absorption cell, and transmitted light formed after target gas absorption is incident on the integral cavity; the transmitted light acts on the quartz tuning fork in a back-and-forth process in the integral cavity; an electric signal output by the quartz tuning fork is collected by a signal collection card, a target signal component is obtained by demodulation of a lock-in amplifier, and a data processing device is used for calculation according to the target signal component to obtain the target gas concentration. The method comprises the following steps: determining optical structure parameters of the integral cavity, and assembling the integral cavity according to the optical structure parameters; and adjusting the position of the quartz tuning fork and the angle of laser entering the integral cavity, so that the laser can repeatedly act on a sensitive area of the quartz tuning fork in a back-and-forth process in the integral cavity.

The invention provides a digital demodulation type quartz MEMS tuning fork trimming device, and belongs to the field of MEMS tuning fork trimming. The device comprises an upper computer and a quartz MEMS tuning fork which are respectively connected with a first controller and a second controller. The upper computer is used for sending a first driving command to the first controller and sending a second driving command and a third driving command to the second controller; the second controller is used for controlling the quartz MEMS tuning fork to work in a gyro function mode according to the second driving command and the first parameter when a driving end mass block of the quartz MEMS tuning fork is roughly repaired; and the fine trimming module is used for performing linear frequency sweeping on the quartz MEMS tuning fork according to the third driving command during fine trimming to obtain a target mechanical orthogonal item, and determining that fine trimming of the driving end mass block is completed when the target mechanical orthogonal item reaches the standard. The trimming efficiency and precision can be considered through double-stage trimming and automatic control, and meanwhile the trimming cost is reduced.

A gas concentration sensing apparatus and a gas concentration measurement method. The gas concentration sensing apparatus comprises a sensor (100), a radio wave generator (200), and a signal processing module (300), wherein the radio wave generator (200) is electrically connected to a signal input end (101) of the sensor (100), and the signal processing module (300) is electrically connected to a signal output end (102) of the sensor (100); the sensor (100) comprises a quartz tuning fork (110) and a sensing micro-wire (120) that are electrically connected; the sensor (100) is used for having a gas to be measured introduced thereto, and allowing the sensing micro-wire (120) to absorb the gas to be measured; the radio wave generator (200) is used for emitting a vibrating radio wave to the sensor (100), such that the quartz tuning fork (110) and the sensing micro-wire (120) resonate upon receiving the vibrating radio wave, and transmitting a mechanical resonance signal to the signal processing module (300); and the signal processing module (300) is used for collecting the mechanical resonance signal and converting same into an electrical signal of a resonance frequency. In the solution, the characteristic that the overall resonance frequency of a quartz tuning fork (110) and a sensing micro-wire (120) changes with the concentration of a gas to be measured is used to directly obtain a corresponding concentration value of the gas to be measured, thereby achieving a simple and efficient measurement process.

The invention relates to the technical field of trace gas optical sensing, in particular to a photoacoustic spectrometry gas detection system and method based on a hollow-core optical fiber and a quartz tuning fork, and the system comprises a signal generation module, a laser modulation module, a hollow-core optical fiber enhanced detection module and a signal processing module, the system performs long-range interaction with to-be-measured gas in the hollow-core optical fiber by modulating laser, thermal expansion generated after light energy is absorbed is transmitted to the mechanically coupled quartz tuning fork through the optical fiber wall, the quartz tuning fork converts vibration into an electric signal through a piezoelectric effect, and finally the gas concentration is obtained through treatment. According to the invention, the bottleneck that the optical path is limited in the traditional technology is broken through, the detection sensitivity is greatly improved, and the application potential in trace and complex environment gas detection is expanded.

The utility model provides a weighting structure of quartz tuning forks, which is used for weighting a plurality of quartz tuning forks distributed in a tuning fork array, and comprises a mask plate which is arranged at an interval with the tuning fork array, and the spacing distance between the mask plate and the tuning fork array is greater than the thickness of a weighting layer on the quartz tuning forks; a mask window is formed in the position, corresponding to each weighting layer, of the mask plate. In the scheme, the mask plate and the tuning fork array are arranged at an interval, and the spacing distance between the mask plate and the tuning fork array is greater than the thickness of the weighting layer on the quartz tuning fork, so that the edge of the weighting layer can be prevented from being adhered to the inner wall of the mask window during weighting; therefore, the problem that in the prior art, a weighting layer of a small and medium-sized quartz tuning fork adheres to a mask to generate silver scraps is solved, and the preparation precision of the small-sized quartz tuning fork is improved.

The invention discloses an acetylene detection device and method based on a composite sensitized quartz tuning fork, and belongs to the field of photoacoustic spectrometry gas detection, and the device comprises the composite sensitized quartz tuning fork, a laser excitation module, a vibration generation module, a signal demodulation module and a main control computer. The inner side of the quartz tuning fork vibration arm is provided with a composite sensitized film composed of a reduced graphene oxide layer and palladium nano-clusters loaded on the surface of the reduced graphene oxide layer. During detection, the main control computer controls the vibration generation module to be in a high-impedance state and drives the laser excitation module to emit modulation laser to penetrate through a tuning fork vibration arm gap, and the signal demodulation module is used for synchronously demodulating a photoacoustic piezoelectric signal output by a tuning fork, so that the concentration information of acetylene gas is obtained. Through the implementation of the invention, the problems that a common quartz tuning fork in the prior art is low in response sensitivity to a trace gas photoacoustic signal and the detection accuracy is influenced by frequency drift caused by environment change due to the lack of a real-time resonant frequency calibration mechanism can be solved.

The application discloses a kind of trace gas detection devices based on optical interference compensation of photo-induced thermoelastic spectrum, the device includes excitation semiconductor laser, laser collimation system, gas chamber of gas to be measured, focusing lens, quartz tuning fork, probe laser, optical fiber beam splitter, optical fiber circulator, single-mode optical fiber, photoelectric detector, signal generator, laser controller, adder, lock-in amplifier and computer.The application is based on the optical interference compensation technology of LITES, while playing the advantage that popper structure can effectively shield thermal noise, a light beam is irradiated on the bottom of quartz tuning fork, to form reference popper cavity, reference popper cavity and sensing popper cavity, which senses the vibration of quartz tuning fork, have the same structural parameters and environmental parameters, the difference between the intensity of the two reflected lights in reference popper cavity and sensing popper cavity is obtained, that is, the light intensity signal is not disturbed by the environment, to improve the long-term stability of popper demodulation method based on LITES technology.

This invention discloses a device for preparing a tuning fork probe and its operating method. The device includes a limiting base plate, a tuning fork clamping assembly, a multi-dimensional displacement platform, a right-angle fixing plate, a probe clamping adjustment assembly, and a needle-cutting assembly. The tuning fork clamping assembly and the multi-dimensional displacement platform are mounted on the limiting base plate, the right-angle fixing plate is fixed to the top of the multi-dimensional displacement platform, and the probe clamping adjustment assembly and the needle-cutting assembly are both mounted on the back of the right-angle fixing plate. The operating method includes tuning fork clamping, alignment and bonding of the probe with the end face of the tuning fork arm, and cutting off the excess part of the probe. The core of this invention lies in the introduction of a compact and highly controllable needle-cutting assembly. The blade can stably enter the gap between the two arms of the quartz tuning fork and achieve precise cutting without disturbing the bonded needle tip, effectively avoiding the damage caused by traditional manual cutting or laser needle cutting methods. This device effectively improves the preparation efficiency and product consistency of the tuning fork probe.

The invention provides a method for optimizing the temperature performance of a quartz tuning fork gyroscope, which comprises the following steps of: introducing an orthogonal deflection angle in a demodulation process to obtain that the ratio of an available orthogonal scale to an in-phase scale can represent the size of an incomplete orthogonal deflection angle of a gyroscope output signal and a reference demodulation signal; and when the actually measured orthogonal deflection angle is obtained, a corresponding physical model is established on the basis of mathematical rules of different deflection angles and temperatures, and real-time monitoring and compensation of the deflection angles at different temperatures are realized, so that when the orthogonal deflection angle is introduced later, the deflection angles at different temperatures can be monitored and compensated in real time. The phase of the reference demodulation signal is orthogonal to the phase of the gyroscope signal, so that the zero offset variation in the full-temperature range is improved, and the hysteresis effect of the gyroscope in the full-temperature range is reduced.

The present invention, in the field of measurement and control circuit technology, discloses a quartz tuning fork resonant gyroscope measurement and control circuit based on time-sharing multiplexing. The measurement and control circuit includes a drive circuit self-excited oscillation circuit and a force feedback and detection circuit. The drive circuit self-excited oscillation circuit includes a first conversion unit, a comparison unit, a regulation unit, and an electronic switch, and the force feedback and detection circuit includes a first switch, a second switch, a third switch, a fourth switch, a second conversion unit, a fifth switch, a sixth switch, a seventh switch, an amplification unit, and a force feedback controller. This allows for high-frequency switching between the excitation of the drive channel and the vibration detection of the detection channel, thereby eliminating electrical coupling between the two. This solves the problem of the electrical coupling between the drive circuit and the detection circuit affecting the zero drift stability of the gyroscope output, thereby improving the zero drift stability of the gyroscope.

The invention discloses a photoinduced thermoelastic spectrum bi-component trace gas detection device and method based on an asymmetric quartz tuning fork, and the device comprises a tunable laser, a laser alignment system, a gas chamber, the asymmetric quartz tuning fork, an impedance amplifier, a control and data acquisition system and a computer. The tunable laser outputs a laser beam containing two modulation frequency components at the same time, the laser beam is shaped by the laser alignment system and then is emitted into the gas chamber, the laser beam and gas to be measured in the gas chamber are subjected to a periodic photo-thermal effect, and then the laser beam is irradiated to a stress sensitive area of the asymmetric quartz tuning fork. Two paths of photo-thermal current signals generated by the asymmetric quartz tuning fork are amplified and converted into two paths of voltage signals by the impedance amplifier, the two paths of voltage signals are synchronously acquired by the control and data acquisition system, finally, filtering and second harmonic demodulation are performed by the computer, and concentration information of gas to be detected is obtained through inversion. According to the invention, the sensitivity, the stability and the system integration degree of double-component trace gas measurement can be obviously improved.

The invention discloses a light-force synergistic photoacoustic spectrum trace gas detection device and method. The device comprises a signal generator, a tunable laser, a laser alignment system, a focusing lens, a gas chamber, a photoinduced shrinkage or elongation material, a quartz tuning fork, a signal amplifier, a data collector and a computer. Different from a traditional off-axis incidence mode, the design of in-plane incidence laser is innovatively adopted, and the laser penetrates through a tuning fork gap along the interdigital plane of the quartz tuning fork and accurately acts on the surface of a photoinduced shrinkage or elongation material at the bottom of the quartz tuning fork. According to the unique structural design and the laser incidence mode, the sound-force dual-mode synergistic effect is achieved. When laser interacts with gas molecules, sound waves can be generated, and meanwhile, the photoinduced shrinkage or elongation material is modulated by periodic laser to generate force with the same frequency as the sound waves. The sound wave and the force simultaneously act on the quartz tuning fork, so that the vibration amplitude of the quartz tuning fork is remarkably improved, and the detection sensitivity of the sensor is further improved.

The present invention discloses a photoacoustic spectrum signal detection circuit and a quartz tuning fork sensor. The photoacoustic spectrum signal detection circuit mainly includes a symmetrical quartz tuning fork sensor, a high-stability active crystal oscillator, a DDS signal generation circuit, a digital phase-locked chip, a counter, a transimpedance amplifier, a resistor, a shaping circuit, a first bandpass filter, a second bandpass filter, a digital-to-analog conversion chip, a microcontroller, a frequency measurement circuit, and a voltage-controlled amplifier circuit. The circuit injects a sinusoidal signal into one cantilever of the quartz tuning fork sensor and excites an acoustic signal, while the other cantilever receives the acoustic signal and converts it into a sinusoidal electrical signal. Laser light passes through the middle of the quartz tuning fork sensor, and as the gas concentration and other properties between the two cantilevers of the quartz tuning fork change, the received sinusoidal signal also changes. The relatively changing frequency signal is tracked by digital lock, and the change in the frequency signal is measured to establish a corresponding relationship with the gas concentration and other properties.

The invention provides a quartz tuning fork probe system with temperature self-compensation, and the system comprises a quartz tuning fork probe which comprises a quartz tuning fork and a probe tip; the temperature acquisition unit is used for acquiring temperature data reflecting the real-time temperature of the quartz tuning fork; the driving detection unit is used for acquiring the resonant frequency of the quartz tuning fork and driving the quartz tuning fork to work at the resonant frequency; and the temperature self-compensation unit is used for adjusting the resonant frequency of the quartz tuning fork in real time based on the collected temperature data and resonant frequency data so as to realize self-compensation of the temperature characteristic of the quartz tuning fork probe in the temperature change process.

The invention discloses a photo-thermal spectrum device and method based on orthogonal pseudo-random code modulation, and the device comprises a control and signal processing unit, a pseudo-random code generator, a laser driver, a tunable laser, a collimator, an air chamber, a focusing lens, a quartz tuning fork, a pre-amplifier, a data collector, and a related demodulator. A pseudo-random code sequence with good self-correlation and cross-correlation characteristics is used for carrying out binary orthogonal modulation on laser intensity, and weak photo-thermal signals are extracted from strong noise through a correlation demodulation technology. The method has the advantages that the method is insensitive to narrow-band noise due to the broadband modulation characteristic, any noise irrelevant to pseudo-random codes can be effectively suppressed by relevant calculation, and the method has extremely high anti-interference capability; related processing is equivalent to long-time energy accumulation, and the noise bandwidth can be compressed; the broadband characteristic of the pseudo-random code enables the pseudo-random code to cover the drift range of the resonant frequency of the quartz tuning fork, and the system is higher in adaptability to environmental changes and higher in stability.

The invention discloses a light-induced thermoelastic multi-component gas detection device and method based on quadrature modulation, which adopts a technical path combining double-path quadrature phase modulation and single-path quadrature demodulation, that is, two tunable lasers are respectively driven by sinusoidal signals with the same modulation frequency but orthogonal phases; the two laser beams are combined by the wavelength division multiplexer, collimated by the collimator, acted by the gas chamber and the gas and focused by the lens and then radiated to the surface of the quartz tuning fork, a piezoelectric signal generated by the quartz tuning fork comprises excitation mixing information of the two gases, and the signal is amplified by the preamplifier and then sent to the lock-in amplifier; and the phase-locked amplifier synchronously calculates two components X and Y which are orthogonal to each other according to a reference signal with the same frequency as the laser modulation signal, and the two components respectively and independently correspond to the concentration information of the two target gases, so that real-time, synchronous and crosstalk-free measurement of the two-component gases is realized.

The application discloses a quartz vibrating beam accelerometer differential measurement system and a use method thereof, which comprises a frequency difference circuit module, a digital frequency synthesis circuit module and a frequency measurement module, the frequency difference circuit module is used for completing subtraction operation of square wave signal frequency; the digital frequency synthesis circuit module is used for synthesizing the minuend frequency and the subtrahend frequency in the frequency difference circuit module; and the frequency measurement module is used for measuring the output frequency in the frequency difference circuit module and controlling the digital frequency synthesis circuit module; according to the synthesized minuend frequency and the subtrahend frequency in the digital frequency synthesis circuit module, the frequency difference circuit module performs difference processing on two square wave signals, and inputs the difference-processed signal into the frequency measurement module, so that the real-time output frequency of the accelerometer is measured, the differential measurement is completed, the frequency and scale factor drift of the quartz vibrating beam accelerometer caused by temperature change can be effectively inhibited, the requirement on the frequency measurement method accuracy can be reduced, and the resolution is effectively improved.