82results about How to "Simple measurement system" patented technology

The invention discloses a flame three-dimensional temperature field measurement imaging device, a flame three-dimensional temperature field measuring device and a flame three-dimensional temperature field measuring method. The imaging device comprises a main lens and a camera detector surface, and is characterized in that a microlens array is arranged between the main lens and the camera detector surface, a virtual focal plane of the microlens array and a virtual image surface of the main lens are coplanar, and the microlens array is used for imaging light rays entering the main lens onto different pixels on the camera detector surface. Compared with the traditional camera, the imaging device provided by the invention can distinguish light ray directions, further establishes a radiation transfer model, obtains a flame three-dimensional temperature field through adopting an inversion algorithm, records radiation information of flame in all directions more accurately, and is more precise in measurement results; and compared with the tomographic technology based on a plurality of cameras, only the single imaging device is needed without using a plurality of cameras, complex synchronization control of the cameras is not required, and the measuring system is simple and easy to implement.

The invention discloses a device for measuring a modulation transfer function of an optical system and a method thereof. A target generator of the device comprises a knife edge target (4), a light source (1) and an electrical machine (3), wherein the electrical machine drives the knife edge target (4), so that an inclined angle beta is formed between the arrangement direction of a knife edge pixel (12) of the knife edge target (4) and that of a pixel (13) of an area array detector, and the inclined angle meets the following condition: ds=d sin beta, wherein the ds is a sampling distance, and the d is the size of the edge length of the pixel of the area array detector. When measuring, the modulation transfer function, the electrical machine drives the knife edge target (4) to rotate at the angle of beta to perform image data collecting and data processing so as to obtain modulation transfer function of the optical system to be measured. The invention adopts the knife edge target to realize an oversampling technology and improve the sampling rate, thereby being capable of measuring the modulation transfer function of the optical system to be measured without a relay amplifying system, being capable of measuring the maximum frequency which is higher than the Nyquist frequency of the area array detector, simplifying a measuring system, and avoiding complex assembling and correcting work when manufacturing apparatuses.

The invention relates to a workpiece burr detection method based on image processing. A LED luminescent semiconductor is used as a light source to vertically irradiate that surface of the workpiece, aCCD camera is used as an image detecting device to continuously photograph that edge of a workpiece, finally, the image captured by the camera is captured by the computer, and then the image is filtered, segmented, the edge of the image is detected, and the edge is fused and processed by the region growth method, when the gray value reaches the set standard, the image does not need to expand, indicating that the edge is formed; then the spindle is determined to remove the pseudo-glitch, and finally the edge of the glitch is extracted. The guide line is obtained from the smallest circumscribedrectangle. The length of the contour, the angle difference between the contour and the reference line, the average distance, the variance and other positional relations are compared to determine whether the edge line is burr or not. The complexity of the method is not high. The measuring speed is fast. The detection accuracy is high, the requirement for the experimental environment is not high, and the measurement system is relatively simple.

A volumetric flow of an analyte, including exhaled air, is fed to a gas sensor unit by used of gas flow device, which can include various sensors for the determination of nitrogen oxides. An oxidation catalyst is used when using an NO2 sensor, which converts nitrogen monoxide to nitrogen dioxide and the gas sensor unit measures the content of nitrogen dioxide. The nitrogen monoxide content is calculated from the nitrogen dioxide content. In order to eliminate cross-sensitivity moisture and ethanol are also measured. The device can be applied to the determination of nitrogen monoxide content of exhaled air.

The invention relates to a testing device for dielectric coefficient of liquid or solid powder matter and testing and calculating methods, characterized in that in the device microwave signal source (1) is connected to the inputting end of slotting coaxial measurement segment (4) by circulator (2) and double directional coupler (3); after it passes through tested matter reflecting wave Pr and transmitting wave Pt are generated; reflecting wave Pr is transferred to matched load (6) by the double directional coupler (3) and the circulator (2); transmitting wave Pt is sent to the matched load (6) by directional coupler (5); incident wave Pi and reflecting wave Pr coupled by the double directional coupler (3) and transmitting wave Pt coupled by directional coupler (5) sent to double-channel power meter (7) respectively at two ends of slotting coaxial measurement segment (4) are sent to computer (8) finally so as to form an integration. It is tested and calculated by the following method. Tested matter is set in the measuring container (12) and amplitudes of reflection coefficient S11 and transmission coefficient S21 are read in computer (8) as testing value for use. Based on testing result dielectric coefficient of tested matter is searched by finite value algorithm combined with genetic algorithm.

The invention discloses a measurement system and a measurement method of a secondary electron emission yield of dielectric material. The measurement system comprises a Faraday cup and a pulse electron gun, wherein an incident beam generated by the pulse electron gun outside the Faraday cup irradiates on a sample through an electronic entrance port on a tube, and an automatic voltage regulator circuit is electrically connected between a sample back electrode and an earth wire, so that the level on the sample surface is kept constant relative to a potential difference between the electron guns. The voltage regulating range of the voltage adjustor circuit is controlled by a feedback control circuit in real time, so as to ensure that charging potential of the sample is compensated in real time, and current probes for measuring net collection current and secondary electron current are respectively connected between the sample and a voltage controlled power source of the voltage regulator circuit, and connected with the Faraday cup. According to the measurement system and the method disclosed by the invention, are simple extra consumer power equipment such as an ion source and the like and related experimental links are not needed, the measurement efficiency is high, and the measurement is continuous without stopping to carry out work such as energy dissipation, surface level measurement and the like after each irradiation pulse, and the measurement error is small.

The invention discloses a dynamic measurement system of digital speckle interference tiny in-plane deformation and a measurement method. The dynamic measurement system is characterized in that emergent light of a low-coherent laser device is divided into transmission light and reflection light through a light splitter; the transmission light is subjected to beam expansion and then irradiates a measured object surface; the reflection light passes through a plane mirror and a beam expanding mirror and then irradiates the measured object surface; diffuse reflection light of a measuring surface is divided into two beams of light through a light splitting prism; the two beams of light pass through the plane mirror, a diaphragm, an imaging lens and the light splitting prism respectively and then are imaged onto a CCD (Charge Coupled Device) camera. The dynamic measurement system disclosed by the invention can be used for carrying out dynamic measurement on the tiny in-plane deformation of a measured object and is a full-field, high-precision and easy-to-operate measurement system.

The invention discloses a performance testing device for a partial discharge ultra-high frequency sensor. The device comprises a gigahertz transverse electromagnetic cell, a vector network analyzer, a polytetrafluoroethylene cover plate, a data processing computer, a checking antenna and the ultra-high frequency sensor to be tested. The vector network analyzer is used simultaneously as signal input and output ends, so that the device is high in cost performance and convenient to implement. The invention further provides a method for testing the performance of the sensor by utilizing the testing device. Time-domain and frequency-domain parameters representative of the performance of the sensor can be simultaneously given, and the advantages of reliability, accuracy and the like are achieved.

The invention relates to a method for quickly measuring the precision of a reflection face of a radiotelescope. The method can effectively solve the problems that in the large-caliber radiotelescope reflection face precision measurement process, measurement time is long, measurement precision is low, the angle of pitch of measurement is fixed, and external hardware equipment is needed for assistance. According to the method as a special phase retrieval microwave holography method, it is only needed that the amplitude of an antenna aperture field is measured, and the retrieval of the phase of the antenna aperture field is carried out according to a certain method. In the method, any stable astronomical radio source can serve as a signal source, and beam patterns are scanned under the antenna focusing condition or the antenna out-of-focus condition through an astronomic receiving machine and a terminal (power radiometer); an antenna aperture phase model is built according to the Zernike polynomials function, iterative operation is carried out on the residual error of a model value and a measured value through the minimization algorithm, and therefore the optimal solution corresponding to the minimum residual error vector is obtained to obtain a Zernike polynomials coefficient, backstepping is carried out to obtain the hole aperture phase distribution of an antenna, and the precision of the reflection face of the radiotelescope can be obtained.

The invention discloses a test method that fast realizes wind tunnel small scale pressure detection; the method comprises the following steps: a set of pressure taps are connected on a balance measuring cable in a wind tunnel via a pressure detection module; the pressure detection module is virtualized as a balance; the pressure on the pressure tap can be obtained via reading a signal on the balance measuring cable; unlike a conventional method in which an electronic scan valve sets massive devices and pipelines in the wind tunnel field, the method only uses the existing balance measuring cable in the wind tunnel to fast obtain the pressure value of the corresponding point in the wind tunnel; the test method is convenient and fast, and has an excellent anti-electromagnetic interference capability.

The invention discloses an online measurement method for revolve-body high-precision moment of inertia. The method includes the steps of 1), motor current and the moment of inertia relation modeling, namely inferring relation of the motor current and the moment of inertia according to the fact that the motor drive torque is in direct proportion to the current and the motor drive torque is equal to multiplication of the moment of inertia and angular acceleration; 2), calibration of the moment of inertia current coefficient and motor shaft moment of inertia, namely calibrating the moment of inertia current coefficient through a plurality of standard blocks with the known moment of inertia and then determining the motor shaft moment of inertia; 3), measurement of the revolve-body moment of inertia, namely calculating the moment of inertia of a revolve body according to the well calibrated moment of inertia by measuring the motor current. With the method, online measurement can be realized, higher measurement precision is achieved, the measurement precision is within 3%, and most of measurement requirements can be met.

The invention relates to a prediction method for power compression of a coil driven loudspeaker without thermal resistance. For arbitrary coil driven loudspeaker, the impedance curve and the temperature variation of a voice coil are measured, the power compression value of a characteristic frequency point is calculated through the computing formula of the power compression without thermal resistance, then a modified coefficient is calculated through the modified formula, and finally power compression curves under different input power conditions are obtained. Based on the measured impedance curve and the temperature variation of the voice coil, the computing formula of the power compression without thermal resistance is adopted for calculating, and the computing formula is as follows: PC is equal to 10log10, wherein, the power compression indicates the relative reducing of the frequency response amplitude of the coil driven loudspeaker under different input power conditions.

The invention discloses a measuring system for large-scale plane directional variation. The measuring system for large-scale plane directional variation includes a line style laser emitter, one-dimensional PSD measuring points, a measuring controller and an information processor, wherein the information processor is in data connection with the measuring controller; the measuring controller is in control connection with the line style laser emitter; the measuring system is provided with a plurality of one-dimensional PSD measuring points, and every one-dimensional PSD measuring point is provided with a one-dimensional PSD sensor; the ray output by the line style laser emitter is transmitted to the one-dimensional PSD sensors; the one-dimensional PSD sensors are in data connection with the measuring controller; and the plurality of one-dimensional PSD measuring points are arranged on a large-scale plane. The invention also provides a measuring method for large-scale plane directional variation. The measuring method can obtain the position variation of each measuring point through coordination of the line style laser emitter with the one-dimensional PSD sensing technology, and can obtain the direction variation of the large-scale plane through solution so as to perform further adjusting or compensation of the large-scale plane.

The invention discloses a mirror surface object three-dimensional shape measurement method and device based on double-screen transmission display. The device comprises a computer, a CCD camera, a liquid crystal display screen and a transparent display screen, wherein the CCD camera, the liquid crystal display screen and the transparent display screen are fixed on an optical platform, and the liquid crystal display screen and the transparent display screen are perpendicular to the optical platform; light paths of an image displayed on the liquid crystal display screen and an image displayed onthe transparent display screen are parallel; a horizontal guide rail is arranged on the optical platform and is perpendicular to the liquid crystal display screen; and the computer is connected with the liquid crystal display screen, the transparent display screen and the CCD camera. The method comprises the following steps: 1, establishing a measurement system; 2, removing a to-be-measured mirrorsurface object to obtain an absolute phase expansion diagram of a reference plane; 3, removing the reference plane, adding the to-be-measured mirror surface object, and obtaining the absolute phase expansion diagram of the to-be-measured mirror surface object according to the method in the step 2; and 4, solving three-dimensional morphology depth information of the to-be-measured mirror surface object.

The invention discloses a terahertz detector based on a multilayer-single-layer graphene junction and a preparation method thereof. Conductive channels in the detector are composed of multilayer-single-layer graphene junctions connected with one another; the multilayer-single-layer graphene junction is an effective sensitive area for terahertz wave detection; under the irradiation of terahertz waves, the photo-thermo-electric effect electromotive force of the multilayer graphene is greater than that of the single-layer graphene, so that a combined photo-thermo-electric effect electromotive force dominated by the multilayer graphene is formed; the combined photo-thermo-electric effect electromotive force is output in a circuit in a voltage or current mode to finally obtain terahertz wave response. In addition, the combined photo-thermo-electric effect electromotive force is regulated and controlled through a gate piezoelectric field, and the responsivity and the sensitivity of the detector can be further improved. Compared with the prior art, by combining the respective advantages of the single-layer graphene and the multi-layer graphene, the responsivity of the detector can be effectively improved, so that terahertz detection with high response speed and high responsivity is realized at room temperature.

The invention provides an optical system and a method for measuring thermal physical property parameters of a solid. The optical system comprises a heating laser production assembly, a detection laser production assembly, a beam combining element, a beam split element, a heating laser receiving assembly, a sample test assembly and a detection laser receiving assembly. The method uses a signal modulating photo-thermal reflection method and belongs to a frequency domain method, and compared with time domain methods of ultrashort pulse laser pumping detection methods and the like, the method has the advantages that mechanical moving components are absent, the measuring system is relatively simple, and light path adjustment is more convenient.

The invention discloses a sleep apnea monitoring device which comprises a respiration sensor, a voltage signal amplifier, a rectifying circuit, a time discriminating circuit and a pulse generator. Compared with the prior art, a measuring system can be simplified, the volume and the weight of the monitoring device can be reduced, an easily operated portable device is provided for diagnosing and treating sleep-related breathing disorder, the sleep apnea monitoring device obtains characteristic pathological information of sleep apnea syndrome (SAS) in a simple way and provides an effective technical means for primary screening, general survey and monitoring of SAS.

The invention discloses a nanometer-resolution total-reflection differential micrometric displacement measurement method and a nanometer-resolution total-reflection differential micrometric displacement measurement device. The device comprises a laser, a single mode fiber, a collimating lens, a depolarization spectroscope, a micro objective, a measured target mirror, a rhombic prism, a convex lens, a differential detector and a driving and display unit. The method comprises that: laser is filtered and collimated, and the filtered and collimated laser is vertically incident onto the depolarization spectroscope; the filtered and collimated laser sequentially passes through the micro objective to reach the measured target mirror, is reversely reflected, refracted by the micro objective and vertically incident into the depolarization spectroscope, enters the rhombic prism, and is totally reflected for at least once in the rhombic prism and emergent; and emergent light beams are converged and incident into the differential detector, signals are transmitted into a driving and display system of the detector to obtain voltage signals reflecting the position changes of the measured target mirror, and the position changes of the measured target mirror are displayed. The method and the device can be used for nanometer-resolution detection, and are widely applied in the field of industrial precision measurement and monitoring.

The invention concerns a measuring system for optical monitoring of coating processes in a vacuum chamber, in which the light source is arranged inside the vacuum chamber between the substrate carrier and a shutter is arranged beneath the substrate carrier and the light-receiving unit is arranged outside the vacuum chamber in the optical path of the light source. The substrate carrier is designed to accept at least one substrate, and it can move across the coasting source in the vacuum chamber, preferably revolving about an axis, whereby the substrate or substrates cross(es) the optical path between the light source and the light-receiving unit for transmission measurement, and the shutter shades a measurement area across the coating source.

Disclosed are an optical fiber system and a measuring method for measuring a turbid medium and a biological tissue optical parameter, comprising light source inputting, optical fiber measuring, controlling, data processing and calculating. The light source inputting is connected with the optical fiber measuring which is connected with controlling, data processing and calculating which are connected with the light source, and the optical fiber measuring is connected with the turbid medium or biological issue. The method is that real-time spectrum signals output by a measuring apparatus stores optical signals with various wavelengths according to the wavelengths; in a light transfer theoretical calculation sub-procedure, the stored real-time optical signals with various wavelengths are demodulated by mathematic treatment and then the actual measured optical signals are calculated; the actual measured optical signals are compared with the calculated optical signals, and then the optical parameter of the measured sample is adjusted to make the differences between the calculated optical signals and the actual measured optical signals less than the preset value, the optical parameter of the measured sample is output finally. The measuring system of the invention is simple and can accurately measure the optical parameter of an original body or living body in no need of leaving the living body sample.

The invention discloses a method for measuring semitransparent material radiation characteristics by the adoption of a multi-frequency modulation laser heating and photo-thermal information reconstruction technology, and relates to a method for measuring semitransparent material radiation characteristic parameters. The method comprises the steps that lasers with different frequencies are used for radiating one side surface of a semitransparent material, a photoelectric detector is used for measuring frequency domain hemispherical reflection radiation signals of the laser incidence side of the material at the incidence laser frequency and frequency domain hemispherical transmission radiation signals on the laser emergent side of the material at the incidence laser frequency respectively, and a thermocouple thermodetector is used for measuring and recording changes of the temperatures on the two surfaces of the material along with time. According to the frequency domain hemispherical reflection radiation signals, the frequency domain hemispherical transmission radiation signals and the temperatures, changing along with time, of the two surfaces and through an inverse problem solution technology, the attenuation coefficient of the semitransparent material and the albedo of the semitransparent material are obtained. According to the method, a direct problem model and an inverse problem model for measuring the attenuation coefficient of the semitransparent material and the albedo of the semitransparent material are established and meanwhile the attenuation coefficient of the semitransparent material and the albedo of the semitransparent material can be measured simply, quickly and accurately by the utilization of the inverse problem solution technology.

The invention belongs to the field of photo-communication, relates to integration of a long-period fiber grating and graphene, and provides a long-period fiber grating spectrum based graphene complex refractive index measuring method. The graphene is transferred to the surface of the long-period fiber grating, the effective refractive index of a cladding mode is obviously changed through the mutual action of the graphene and an evanescent wave on the surface of a first-order each cladding mode, so that the shift of the resonant wavelength in a long-period fiber grating transmission spectrum is caused. The numerical values are compared to calculate to obtain a relationship table of the complex refractive index of the graphene and the offset of the resonant wavelength, so that the complex refractive index of the graphene is measured. A measuring system in the method is simple in structure, the influences of an optical fiber on the graphene are taken into full consideration in the measurement process, and as the long-period grating is written in an optical fiber core, the evanescent wave in the cladding mode is led to the surface of the graphene without corroding a cladding layer of the optical fiber, and therefore, the structure strength of the optical fiber is guaranteed. The method can also be popularized to measure the refractive indexes of other thin film materials and to design an optical fiber sensor.

The invention relates to a particle trajectory speed measurement device and method combining compound blur and binocular imaging. A light source illuminates a to-be-measured flow field, double lenses and double cameras are fixedly connected with each other in a one-to-one correspondence manner; the constructed two sets of lenses and cameras are arranged at a fixed angle, and the two sets of lenses can observe the to-be-measured flow field at the same time; a signal generator provides a stroboscopic signal for the light source, single-frame multi-exposure combining long exposure and short exposure is achieved; and the signal generator provides a synchronous trigger signal for the double cameras and the light source; the double cameras shoot flow field images and send the flow field images to a computer; and the computer obtains single-frame multi-exposure images of a binocular vision system under two different visual angles, and calculates the three-dimensional flowing speed and acceleration of particles of the to-be-measured flow field. With a three-dimensional flow field motion information acquisition technology combining particle trajectory speed measurement, compound blur and binocular imaging adopted, a microscopic flow field and a high-speed flow field are tested; a measurement system is simplified, a data processing process is optimized; and three-dimensional flow field measurement of the microscopic flow field or the high-speed flow field can be realized.

The invention relates to a device special for online measurement of the dryness of a steam injection well, composed of a capacitance sensor, a temperature sensor, a pressure sensor, a signal processor, a singlechip, a memory and a computer, wherein the capacitance sensor, the temperature sensor and the pressure sensor are connected to the signal processor respectively; the signal processor is connected to the singlechip which is connected to the computer; the signal processor, the singlechip and the memory are mounted on a circuit board; the circuit board and a power supply battery are mounted in a vacuum flask; the capacitance sensor is tubular; one end of the capacitance sensor is fixedly connected to the vacuum flash; and the temperature sensor and the pressure sensor are fixed to the other end of the capacitance sensor. The device employs the cylindrical capacitance sensor for measuring the humidity of steam, and performs the measurement of the dryness of wet steam based on the difference between water and steam in dielectric constant; and the measurement system is simple without extracting steam for sampling, and low in requirements for the environment; the cost of equipment is low; and the operation process is simple and convenient.

The invention relates to a structured light micro-nano three-dimensional shape measurement method based on a focused evaluation algorithm. The traditional three-dimensional measurement method based ona focusing evaluation function has the characteristics of simple measurement system and no damage but hardly can measure an object having a smooth surface structure and insufficient textures due to the essence of judging a focus level according to texture information of the object. The invention provides a three-dimensional shape profilometry combining structured light illumination and the focusing evaluation function, and measurement on an object with a smooth surface and a rough surface coexisting can be realized. In a measurement system, a pattern produced by a DMD is projected to the surface of an object, the object is longitudinally scanned and a to-be-processed picture is obtained, for one pixel point, a fuzzy-to-clear and clear-to-fuzzy process is shown in an image sequence, wherein the focused evaluation algorithm is used for determining a picture position where imaging of the pixel point is the clearest, then a curve fitting algorithm is combined for extracting a precise focusing position, and all the pixel points are traversed, so that a three-dimensional shape of the object can be obtained.

The invention relates to an asynchronous motor excitation mutual inductance curve measuring system and a measuring method. The system comprises a controller, a three-phase asynchronous motor, a sensing unit and an upper computer. The sensing unit measures an output torque and rotor angular frequency information in real time and sends to the controller. The controller is connected with the sensingunit, the three-phase asynchronous motor and the upper computer so as to control the work of a motor. The upper computer sets different excitation current reference values, a slip angle frequency is adjusted in real time so that a rotor magnetic field is accurately oriented, the maximums of the motor output torques corresponding to different excitation current reference values are recorded, and the excitation mutual inductance values corresponding to different excitation current reference values are solved to acquire an excitation mutual inductance curve. By using the measuring method, the excitation mutual inductance curve of the motor can be measured quickly and accurately. Excitation mutual inductance curve data can be used as a look-up table used for a rotor magnetic field oriented vector control algorithm, which significantly improves rotor magnetic field orientation accuracy, torque control accuracy and weak magnetic control stability.

The invention provides an intelligent magnetic induction flux sensor which is low in power dissipation, high in compatibility and good in universality, and output signals are digital signals. According to the technical scheme, liquid flows through the flux sensor, an impeller is driven to rotate through a guider, voltage in direct proportion to average flux speed is sensed, electromagnetic induction voltage signals are transmitted to a converting processing circuit, square signals with the frequency and the flux in direct proportion are obtained by converting, a modulation amplifying circuit amplifies weak electromagnetic induction signals in a modulation mode, square signals with the duty ratio of 50% are obtained by converting, high-frequency parts in the signals are filtered out through an RC low-pass filtering circuit, a detector circuit shapes the square signals and sends the square signals to a signal processing module which computes collected signals, computing results are sent to a communication module and a data storage module, and by processing and computing of a signal data processor, flux information is sent to terminal equipment through the communication module.

The invention discloses an optical lens residual polarization testing device. The optical lens residual polarization testing device is characterized in that an integrating sphere with three ends beingopen and halogen tungsten lamps is adopted to serve as a light source, a focusing lens is adopted to perform focusing on a light beam, and a polarizing optical system formed by an achromatic filter,a polarizer and a 1 / 4 wave plate is adopted to provide a measurement light beam with a specific polarization state and a specific wavelength; a large-aperture off-axis parabolic reflecting mirror is adopted to perform collimation on the measurement light beam, and then the collimated measurement light beam passes through a tested optical lens; and a photoelectric detector is utilized to measure apolarization optical signal amplified by an amplifier, so that optical lens residual polarization degree measurement with the wavelength range being 0.45 micron-1.1 microns and the polarization degreemeasurement range being 0.1-0.9 is achieved.

The present invention discloses a structure light-based micro-nanostructure two-dimensional super-resolution detection method. According to the method, when no optical gratings exist in a projection device, a frame of grayscale image of an image pickup device is obtained; in the context that other conditions are unchanged, an optical grating is added into the projection device, and the image pickup device obtains a frame of stripe-deformed structured light field image; Fourier transformation is performed on the two images separately, two obtained spectrum formulas are normalized, and subtraction operation is performed on the two normalized spectrum formulas, so that a fundamental frequency component can be obtained, two parts of the fundamental frequency component which are obtained after separation is performed are shifted to correct positions separately, the fundamental frequency component and a zero frequency component are superposed according to a certain weight, so that complete spectrum information can be obtained; and a two-dimensional super-resolution image detection result is obtained through restoration. With the method of the invention adopted, resolution can be improved; in a measurement process, a frame of gray image is adopted to eliminate frequency aliasing, so that the separation of the zero-frequency component from the fundamental frequency component can be realized, and therefore, measurement efficiency can be improved; and a phase-shift device is not needed when the image is collected, so that a measurement system can be simplified.

The invention relates to a maladjustment error correction method for a large-aperture and large-view-field telescope. The method comprises the steps of: (1) collecting under-sampling imaging light spots of on-axis and off-axis view fields by using a far-field detector; (2) performing target extraction and view field matching on the imaging light spots of each view field on the axis and outside theaxis; (3) calculating an image definition function of the under-sampling imaging light spots of each view field in an initial maladjustment state; (4) calculating a new secondary mirror position by using an optimization algorithm, and changing the secondary mirror position through a six-degree-of-freedom driver; (5) acquiring far-field under-sampling imaging light spots of each view field again,performing target extraction and view field matching, and calculating an image definition function of the light spots of each view field; and (6) judging whether the correction result meets a termination condition or not, if yes, ending the correction process, and otherwise, repeating the steps (4)-(6). According to the invention, on the basis of the image definition function of the far-field under-sampling imaging light spots, the online, closed-loop and high-precision correction process of the maladjustment error of the large-aperture and large-view-field telescope can be realized by using an optimization algorithm.