99 results about "Photoacoustic effect" patented technology

The invention provides a network defense capability verification method and system based on intrusion attack simulation. According to the method, network dynamics and a photoacoustic effect simulation technology are creatively fused, and network abnormal traffic equivalent to real attacks is dynamically excited by constructing a photoacoustic coupling waveform driven by network topology; reversely analyzing the vulnerability characteristics based on the protocol interaction entropy, and generating an attack instruction with a space-time cooperation characteristic; utilizing a phase matching algorithm to precisely couple the attack behavior and the network dynamic disturbance to form a defense response track capable of being quantitatively analyzed; and finally, through an asymmetric correlation model, analyzing a dynamic relationship between trajectory deformation and a node survival state, and realizing objective quantitative evaluation of defense efficiency. According to the technical scheme provided by the embodiment of the invention, high-precision quantitative verification of the virtual-real combined network security defense capability can be realized, and the real-time performance and credibility of defense strategy evaluation are improved.

The invention discloses a porcelain insulator nondestructive testing device and method based on chirp modulation photoacoustic spectroscopy. The device comprises a signal generator, a signal processing module and a signal processing module, the laser is connected with the signal generator; the power amplifier is connected with the laser; the laser collimator is connected with the power amplifier; and the signal collector collects the sound wave signals, converts the sound wave signals into electric signals, transmits the electric signals to the computer through a cable for data processing, obtains a spectrogram of the sound wave signals, and judges whether defects exist in the porcelain insulator or not according to the spectrogram. According to the porcelain insulator nondestructive testing device adopting chirp modulation and photoacoustic spectroscopy, characteristic frequency scanning is achieved through chirp modulation, a porcelain insulator acoustic signal spectrogram is obtained through the solid photoacoustic effect, non-power-cut nondestructive testing of porcelain insulators can be achieved, and the detection efficiency of porcelain insulator defects is greatly improved.

The invention discloses a medical cosmetology method and device based on a photoacoustic effect. Existing skin anti-wrinkle and anti-aging photoelectric equipment such as radio frequency and ultrasound has the problems of pain, discomfort, limited application depth, unstable flash type light source energy output and the like. According to the method, pulse laser with a specific wave band and pulse duration is utilized to irradiate the skin to generate a photoacoustic effect, 400-700nm of the pulse laser acts on a surface layer, 700-1300nm of the pulse laser can reach a deep layer of 50mm, collagen regeneration and wrinkle resistance are promoted, and the method is painless and radiation-free. The device comprises a laser generating part, a light splitting part, a combined lens part and the like, a controller coordinates all the parts to work, a steering engine adjusts a reflector to control the laser depth, and an ultrasonic sensor assists. The system has the advantages that energy is accurately controlled, the system is suitable for skin tissues of all layers, the defects in the prior art are effectively overcome, and a safer and more efficient new scheme is provided for the field of medical cosmetology.

The present invention discloses a multi-component gas concentration detection system, which relates to the field of gas concentration detection, and comprises: a light source, which is used for emitting detection light covering the absorption wave band of a target gas; the light splitting assembly is used for dispersing the detection light and at least splitting the detection light into a first light beam and a second light beam; the air chamber is provided with an optical signal detection module and an acoustic signal detection module; the first light modulator is used for carrying out wavelength selection and modulation on the second light beam; wherein the first light beam is received by the light signal detection module to form an absorption spectrum detection light path; the second light beam is absorbed by the gas to be detected and then excites a sound wave signal through a photoacoustic effect, and the sound wave signal is received by the sound signal detection module to form a photoacoustic spectrum detection light path. By adopting the scheme, synchronous detection of multi-component gas, compactness of a detection structure and high-sensitivity detection of low-concentration gas can be considered.

The invention relates to the field of ultrasonic flaw detection, in particular to an ultrasonic nondestructive flaw detection system based on a photoacoustic effect, which comprises a photoacoustic excitation module used for emitting excitation laser to scan the surface of a detected object and inducing the photoacoustic effect to generate ultrasonic waves on the surface of the detected object through the excitation laser; the optical detection module comprises a detection laser and a four-quadrant detector, the detection laser is used for emitting detection laser, the detection laser is incident to a detection point on the surface of the detected object at a preset inclination angle, and the four-quadrant detector is used for receiving the detection laser reflected by the detection point; and the computer is connected with the four-quadrant detector, and is used for receiving the current signal output by the four-quadrant detector, calculating the light spot offset of the center of the detection light spot relative to the center of the four-quadrant detector, and calculating the internal damage position of the detected object by analyzing the time domain characteristic of the light spot offset. According to the invention, the defects of contact detection limitation and coherent light interference technology are overcome, the sensitivity and applicability are improved, and the cost is reduced.

The invention discloses a Fourier photoacoustic gas detection device and method, and belongs to the technical field of gas detection. In order to solve the problems that the anti-interference capability of an existing Fourier transform photoacoustic spectrum on a sound signal is limited and the detection sensitivity is low, the Fourier photoacoustic gas detection device is designed, and a super-continuum spectrum broadband light source is used as an excitation light source of a photoacoustic effect; uniform intensity modulation of wide-spectrum light is achieved through the intensity modulation assembly, and phase modulation is achieved through the interferometer assembly. The broadband interference light emitted through double modulation acts with gas molecules to generate wide-spectrum mixed sound waves, and the quartz tuning fork sound measurement assembly extracts resonance components in the wide-spectrum mixed sound waves and converts the resonance components into electrical signals; the generated electrical signal is processed by the signal amplification assembly, the phase-sensitive demodulation assembly and the Fourier transform assembly in sequence, and component discrimination and concentration inversion of the target gas are realized by the processed signal.

The invention discloses an unmanned aerial vehicle control system and method, and relates to the technical field of unmanned aerial vehicle control, the control system comprises a ground control end and an unmanned aerial vehicle end, the ground control end comprises a light source module, a signal coding unit and a light beam directional emission module, the unmanned aerial vehicle end comprises a photoacoustic receiving module, a signal decoding and processing unit and a flight control execution module, the system detects emitted sound waves through a photoacoustic effect, reversely deduces characteristic information of the intensity and frequency of optical signals, uses the optical signals as an information carrier, and performs photoacoustic conversion and acoustic signal processing, so that the flight control performance of the unmanned aerial vehicle is improved. According to the system, remote control over the unmanned aerial vehicle is achieved, meanwhile, a photoacoustic conversion and encoding and decoding mechanism is introduced, high-precision and long-distance transmission of control instructions of the unmanned aerial vehicle is achieved, and therefore the capacity of a receiving end for capturing weak signals is enhanced, and the system can flexibly deal with the signal attenuation problem under different illumination conditions and flight environments.

The invention discloses non-contact photoacoustic imaging equipment and method based on leakage Lamb wave detection, in the equipment, a photoacoustic excitation unit excites Lamb waves on the surface of a to-be-detected plate-shaped sample through a photoacoustic effect; the automatic scanning unit drives the to-be-detected plate-shaped sample to move along the scanning direction, so that the two-dimensional full-coverage scanning of the to-be-detected plate-shaped sample by the photoacoustic excitation unit is realized; the signal detection and amplification unit captures the leakage Lamb wave signal and carries out signal amplification; the data acquisition unit acquires the amplified signal in real time and transmits the signal data to the signal processing and imaging end; and the signal processing and imaging end is respectively in communication connection with the photoacoustic excitation unit, the automatic scanning unit and the data acquisition unit, and performs signal acquisition, storage, analysis and imaging processing. The photoacoustic effect excitation technology, the high-sensitivity signal detection technology and the automatic scanning imaging technology are fused, and efficient, accurate and non-contact detection of the surface and subsurface defects of the plate-shaped material is achieved.

Apparatus and methods are described for treating an occlusion in a blood vessel. A catheter is inserted into the blood vessel. An irradiation unit is driven to emit probing radiation such that the probing radiation is directed toward the occlusion, and returning radiation which is returned in response to the probing radiation impacting the occlusion, is detected. A composition of at least a portion of the occlusion is derived based on a signature that is indicative of the composition within the returning radiation. The irradiation unit is driven to irradiate the portion of the occlusion by emitting treatment radiation having a set of irradiation parameters. The set of irradiation parameters is determined to modulate between a photoacoustic effect of the treatment radiation and a photothermal effect of the treatment radiation, based on the composition of the portion of the occlusion. Other applications are also described.

The invention relates to a near-infrared two-region small organic molecule fluorescent probe with a photoacoustic effect and a preparation method and application thereof.The NIR-II small fluorescent molecule is of a tripolymer structure, is obtained by polymerizing three benzothiadiazole near-infrared two-region small organic molecules through the Schiff base generation reaction of amino and ketone, has good biocompatibility, and can be used for preparing a near-infrared two-region small organic molecule fluorescent probe with the photoacoustic effect. The fluorescence-photoacoustic dual-mode imaging material has the advantages of good optical property, photoacoustic property and photothermal property, no toxicity, good biocompatibility, easy absorption and metabolism by organisms, and realization of fluorescence-photoacoustic dual-mode imaging of osteosarcoma mice.

The application discloses a kind of resonance quartz enhanced dual optical comb photoacoustic spectroscopy gas detection devices, device includes dual optical comb source, acoustooptic frequency shift component, quartz resonant component, signal amplification component, phase-sensitive demodulation component and normalization component;Dual optical comb source is as the excitation light source of photoacoustic effect, it realizes real-time frequency shift by acoustooptic frequency shift component;Dual optical comb source is emitted by acoustooptic frequency shift component and after acting on gas molecule, produces multi-heterodyne sound wave, and quartz resonant component extracts resonance component therein and converts it into electrical signal;The electrical signal generated is successively processed by signal amplification component, phase-sensitive demodulation component, normalization component, and the composition discrimination of target gas and concentration inversion are realized by signal after processing.This application improves the structure and detection mode of dual optical comb photoacoustic spectroscopy, completes the resonance detection of dual optical comb photoacoustic spectroscopy, improves the detection sensitivity of system by acoustic and electrical two-stage filtering, and increases the dynamic range of system.

The invention relates to a photoacoustic liquid viscosity detection device and method based on spectrum resolution, and belongs to the field of photoacoustic detection and liquid physical property analysis. The device comprises a solid-state laser, a collimating lens, a plane mirror, a plate-type semitransparent mirror, a microscope objective lens, a photodiode, a photoacoustic coupling cavity, a rectangular prism group, an ultrasonic transducer, a pre-signal amplifier, a digital oscilloscope and a computer. Pulse laser is focused to a liquid sample after being processed by an optical path to excite a photoacoustic effect, an ultrasonic transducer receives a signal and converts the signal into an electric signal, after a digital oscilloscope synchronously samples, a computer extracts a frequency spectrum full width at half maximum (FWHM) through fast Fourier transform, and non-contact detection is realized based on a negative correlation between the frequency spectrum full width at half maximum and viscosity. The method can overcome the defects of large sample size, mechanical contact and the like of a traditional method, and is suitable for high-precision viscosity detection of biological tissues and industrial samples in the field of biomedicine.

The application discloses a kind of quick detection device of gas content in transformer oil, it is related to the technical field of power transformer;Quick detection device of gas content in transformer oil includes first air pump, second air pump, gas separation structure, booster oil pump, circulation structure and gas detection device;First air pump forms negative pressure environment above the oil surface in heating inner bag, and carries out atomization spray to oil by circulation structure, can be fully released from dissolved gas in oil, greatly speeds up the gas release speed in oil liquid;After enrichment by pressurization, the gas concentration of the gas after release is improved, to avoid the detection deviation caused by too low gas concentration even missed detection;The application also designs laser detection structure based on photoacoustic effect and heat cleaning structure for removing residual water vapor;The device provided by the application shortens the overall time consumption of gas release and detection in transformer oil, and guarantees the accuracy of oil release gas detection.

The present invention discloses a method for generating sound waves in the air using a pulsed laser. The device for generating sound waves is composed of a pulsed laser and an optical modulation system. The pulsed laser is emitted by a pulsed laser and then acts on water vapor in the air after passing through the optical modulation system. The water vapor absorbs the heat energy of the pulsed laser. After the pulsed laser passes through, the water vapor temperature instantly rises and expands, thereby generating pressure waves in the area of ​​action, that is, generating sound waves through the photoacoustic effect. In addition, a three-color visible light laser is used to illuminate the area of ​​action for imaging. The structure of the method for generating sound waves in the air using laser pulses proposed by the present invention is simple. Since water vapor can still be generated even in air with low relative humidity, the effect can be achieved by only following the above steps. The method has research value in the manipulation of microparticles, biological imaging, space imaging, sound communication, and naked-eye three-dimensional display.

An oxidation corrosion product thickness on-line measurement method based on a photoacoustic effect comprises the following steps: modulating laser with a specific frequency to irradiate on the CRUD surface of a fuel cladding, monitoring an acoustic wave signal emitted by the CRUD surface by using a piezoelectric sensor, and establishing an on-line conversion model of the acoustic wave signal and the CRUD thickness so as to obtain visual thickness real-time data. On the condition that the original environment of the CRUD is not damaged, online in-situ measurement is carried out on the thickness of the CRUD, and it is ensured that the real thickness of the CRUD in the growth environment can be accurately reflected by measurement data. Through the method, the dynamic growth behavior characteristics of the CRUD thickness can be obtained, so that more accurate monitoring and guidance are provided for safe operation and fuel management of a reactor.

The invention provides a differential photoacoustic gas sensing system and method based on cross-correlation demodulation, and is suitable for the fields of trace gas monitoring, industrial process fine control and environment detection. The system comprises a gas excitation light source, a symmetrical double-probe gas sensor, an optical fiber circulator, a wide-spectrum light source, a 1 * 2 optical fiber coupler, two pieces of plain glass, a photoelectric detection array and a computer, acoustic wave signals excited by the photoacoustic effect generate difference superposition cavity length changes on the symmetrically-arranged double cantilever beams, and environment noise triggers cavity length responses which are counteracted in the same direction. The system adopts an optical cross-correlation demodulation algorithm to track peak displacement of a cross-correlation function in real time, dynamically demodulates cavity length change information, and inverts the gas concentration according to the information. According to the design scheme, effective photoacoustic signals are remarkably enhanced, meanwhile, effective suppression of environment vibration noise is achieved, and finally the trace gas detection system integrating the advantages of miniaturization, high sensitivity and low cost is constructed.

The application discloses an online measurement method for the thickness of oxidation corrosion products based on the photoacoustic effect, which comprises the following steps: modulating laser irradiation of a specific frequency on the CRUD surface of a fuel cladding, monitoring the sound wave signals emitted by the CRUD surface by using a piezoelectric sensor, and establishing an online conversion model of the sound wave signals and the CRUD thickness, so that intuitive real-time thickness data can be obtained. The thickness of the CRUD is measured online and in situ without destroying the original environment of the CRUD, so that the measurement data can accurately reflect the real thickness of the CRUD in the growth environment. Through the method, the dynamic growth behavior characteristics of the CRUD thickness can be obtained, so that more accurate monitoring and guidance can be provided for the safe operation and fuel management of a reactor.

The invention relates to the technical field of electrical equipment testing, and particularly provides a space charge detection device and method based on optical measurement. The space charge detection device based on optical measurement comprises a sensing acquisition array which is uniformly distributed around detected equipment in the circumferential direction, full-surrounding detection of space charges is achieved, collaborative design of four optical detection technologies is adopted, multi-dimensional detection of the space charges is achieved through the complementary effect of Raman scattering, the photoacoustic effect, LIBS and the photoelectric effect, and the detection accuracy of the space charges is improved. The detection limitation of a single technology is made up; according to the space charge detection method based on optical measurement, a space-time synchronization-weight distribution-feature fusion algorithm and a signal-to-noise ratio-based adaptive weight distribution fusion algorithm are adopted, space-time synchronization calibration and Kalman filtering are combined, the problems of space-time inconsistency and random errors of multi-source data are solved, and the precision of data fusion is improved.

The present invention relates to a photo-acoustic spectroscopy gas cell designed for the identification of gases. The system comprises a gas chamber for containing a gas sample and a light receiving portion that receives excitation light capable of inducing a photo-acoustic effect in the contained gas. A cantilever is mounted at / within the gas chamber. The cantilever is specifically adapted with resonance characteristics that enable it to resonate in response to the photo-acoustic excitation generated within the gas cell. A measurement unit within the system is configured to analyze the response of the cantilever to the photo-acoustic effect, thereby determining the identification of the gas based on this response. This invention provides a precise and reliable way for gas analysis and identification

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.

The invention discloses a single-pixel imaging method and device for single acquisition, which can be used in the technical field of imaging, and the method comprises the steps: collecting a target ultrasonic time sequence signal corresponding to a pulse light beam carrying to-be-measured object information for a single time; and based on the target ultrasonic time sequence signal, utilizing a trained mapping model to reconstruct an optical pattern corresponding to the to-be-measured object, and obtaining a target image. Thus, by means of the photoacoustic effect, single-pixel imaging of single-time acquisition is achieved through single-point single-time detection, and therefore the imaging speed is increased.

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 an ultrasonic imaging system and a synchronization control method. In an ultrasonic imaging system that images the position of an insert using a photoacoustic effect, an optical pulse period and a reception period are correctly synchronized. An insertion member inserted into a living body (16) has a light absorbing element (18a) that absorbs a light pulse and generates a photoacoustic wave. The analyzer (52) calculates a synchronization deviation from the photoacoustic wave signal sequence included in the received signal sequence before the phasing addition. The synchronization controller (54) changes the optical pulse period or the reception period in accordance with the synchronization deviation. The synchronization deviation may also be calculated on the basis of a pseudo received signal column corresponding to the received signal column.

The present invention provides a hydrogen detection device based on photoacoustic effect, comprising a body; a cavity is provided in the body, and an air inlet, an air outlet, a laser incident port and a microphone connected to the cavity are provided on the body; the air inlet and the air outlet are used to pass the gas to be tested into the cavity; the laser incident port is sealed with a lens for laser entry; a diaphragm is provided in the cavity, and the diaphragm includes a germanium sheet that is deformed when irradiated with laser, and a palladium film that is arranged on the germanium sheet and expands after absorbing hydrogen; the microphone is used to detect the sound waves generated by the deformation of the diaphragm, and convert them into analog signals for output. The present invention adopts the photoacoustic effect of the germanium sheet and superimposes the gas sensitive characteristics of the palladium film, so that the photoacoustic spectroscopy technology can be used to detect hydrogen, filling the gap in this technology.

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 discloses a kind of detection methods for internal defects of plastic package component, it is related to defect detection technical field, comprising the following steps: the pretreatment of plastic package component;Photoacoustic signal acquisition;Time-domain waveform extraction and analysis.The application uses the above-mentioned detection method for internal defects of plastic package component, measures the photoacoustic image of different plastic package components using photoacoustic detection system based on photoacoustic effect, extracts the time-domain waveform at different positions of plastic package component along the propagation direction of laser and ultrasonic wave, realizes the identification, positioning and defect type analysis of internal defects of plastic package component by analyzing the reflection peak position, shape, intensity characteristics of time-domain waveform, distinguishes the defect area and defect type in plastic package component using photoacoustic effect, provides a new means for nondestructive testing of internal defects of plastic package component, and has important significance for improving the reliability of plastic package component.

The invention relates to the technical field of VOC detection, in particular to an ultra-sensitive chemical equipment liquid volatile matter VOC detection system and method.The detection system comprises a sampling and enriching module used for conducting in-situ sampling and enriching low-concentration VOC at a detection point, improving the sample concentration and facilitating follow-up detection; the detection module is used for detecting the VOC concentration by adopting an excitation photoacoustic effect and eliminating background interference; the data processing and analyzing module is used for collecting the detection signal, analyzing and calculating the detection signal and outputting a VOC concentration value; and the intelligent calibration module is used for collecting environmental parameters, automatically calibrating the parameters of the detection system according to the change of the environmental parameters, and optimizing the detection range. According to the invention, rapid detection of a trace amount of leaked VOC can be effectively realized, the detection efficiency is improved, the leakage condition can be found in time, greater harm is avoided, and the production safety is guaranteed.

A system and method for protein detection are provided, configured to non-invasively identify proteins exhibiting specific structural conformations within a biological target. The system comprises a light source operable to irradiate the target at a predetermined pulse cycle, a sound detection device configured to capture acoustic signals generated via the photoacoustic effect, and an information processing unit that analyzes the detected acoustic signals to determine the presence or accumulation of a target protein. This technique facilitates early-stage detection of disease-associated proteins, such as amyloid-β and misfolded α-synuclein fibrils, without requiring complex imaging modalities or invasive biopsy procedures.

The application discloses a system for passive terminal communication, and belongs to the technical field of laser communication. The system comprises an optical-acoustic communication relay node module and a plurality of passive photoacoustic terminal modules. The optical-acoustic communication relay node module comprises a multi-channel encoder unit, an encoded laser unit, a listening laser unit, a beam control and tracking emission unit, a photoelectric detector unit and a decoding and communication exchange processing unit. The passive photoacoustic terminal module is composed of an optical-acoustic effect material. The application realizes bidirectional optical-acoustic communication between a plurality of passive terminals through the optical-acoustic communication relay node module. The application realizes networked, multi-user and real-time bidirectional communication between passive terminals while maintaining the advantages of no power supply and simple structure, solves the problems of multi-user access and relay forwarding in point-to-point optical-acoustic communication, and can be applied to the fields of non-electric environment, strong electromagnetic interference and secret communication.

The invention discloses a photoacoustic measurement method. The photoacoustic measurement method comprises the steps that a to-be-measured sample is measured based on the photoacoustic effect, an actual measurement spectrum representing the time domain change of the reflectivity of the to-be-measured sample is collected, the to-be-measured sample comprises N layers of thin films, and N is larger than or equal to 1; obtaining a target echo of each layer of film and a theoretical time value when the target echo reaches the upper surface of the to-be-tested sample; based on the theoretical time value of the target echo, obtaining a spectral characteristic peak search range of the corresponding layer of film; according to the actually measured spectrum and the spectral characteristic peak search range corresponding to each layer of thin film, acquiring an actually measured time value of the target echo of each layer of thin film reaching the upper surface of the sample to be measured layer by layer from the top layer of thin film; and according to the actually measured time value, establishing an equation set comprising to-be-measured parameters, and solving the equation set to determine the to-be-measured parameters which comprise the thickness of each layer of film of the to-be-measured sample. According to the technical scheme of the embodiment of the invention, the physical model can be simplified, and the film thickness measurement precision and calculation speed are improved.