Atomic force microscope imaging noise real-time control method and system

Abstract

The invention provides an atomic force microscope imaging noise real-time control method and system, and the method comprises the steps: building a zero-scanning noise template, processing zero-scanning data formed by zero-scanning imaging of an atomic force microscope, obtaining all noise frequency bands of the zero-scanning data, and forming a noise deduction template; wherein in the zero-scanning imaging process, all motion dimensions, used for zero-scanning imaging, of the atomic force microscope are kept still; and real-time scanning imaging noise suppression: performing noise deduction by using a noise deduction template in the real-time scanning imaging process of the atomic force microscope. According to the technical scheme of the invention, the noise deduction template is obtained for the current environment of the atomic force microscope, and the method can deal with the characteristics of complex noise and vibration sources, abundant frequency spectrums, strong time-varying characteristics and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of atomic force microscope imaging, and in particular to a real-time control method and system for atomic force microscope imaging noise. Background Art

[0002] Atomic force microscopy is an important scientific instrument for studying the surface morphology and physical properties of materials at the nanoscale. Atomic force microscopy senses the structure and properties of the surface of a material through the extremely weak atomic interaction between the surface of the sample to be tested and the micro-force sensitive element composed of the probe and micro-cantilever. Since this micro-force sensitive element has extremely high sensitivity, it is also very sensitive to environmental vibration and noise. Therefore, the imaging quality of the atomic force microscope is very dependent on the level of vibration and noise suppression.

[0003] At present, passive or active vibration isolation methods are commonly used in atomic force microscope systems to suppress vibration and environmental noise. For example, an air floating platform is used on the base of the atomic force microscope to isolate the base from the surrounding environment, which can prevent the environmental vibration from coupling to the measurement mechanical circuit through the base; the core measurement unit of the atomic force microscope usually uses a soundproof cover to block the audio noise of the external environment to reduce the vibration of the microcantilever caused by the excitation of sound waves in space. In addition to the above-mentioned passive vibration isolation methods, active vibration and noise compensation technology is also used in some atomic force microscope systems. For example, voice coil motors, piezoelectric actuators and other components are installed under the base support platform, and their high dynamic movement capabilities are used to achieve reverse compensation for environmental vibrations, so as to achieve the purpose of improving the stability of the platform.

[0004] When the atomic force microscope system is used in an industrial production environment, the noise and vibration it faces have the characteristics of complex sources, rich spectrum, and strong time-varying. Whether it is passive vibration isolation means or active vibration isolation means, there are certain shortcomings: passive vibration isolation tables and soundproof covers are usually designed for specific noise modes, and it is difficult to achieve ultra-wide spectrum noise suppression through existing technologies. The active vibration compensation capabilities provided by active actuators such as piezoelectric and voice coil motors are usually expensive and have limited load capacity. Summary of the invention

[0005] The present invention provides a real-time control method and system for atomic force microscope imaging noise, so as to solve the problems that the existing passive vibration isolation is difficult to achieve ultra-wide spectrum noise suppression, and the active actuating element vibration isolation is expensive and has limited load capacity.

[0006] In order to solve the above technical problems, the present invention is achieved through the following technical solutions:

[0007] According to a first aspect of the present invention, a method for real-time control of atomic force microscope imaging noise is provided, comprising:

[0008] A zero scan noise template is established, and the zero scan data formed by the zero scan imaging of the atomic force microscope is processed to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary;

[0009] Real-time scanning imaging noise suppression: During the real-time scanning imaging process of the atomic force microscope, the noise subtraction template is used to perform noise subtraction.

[0010] Preferably, when suppressing the real-time scanning imaging noise, continuous m lines of real-time scanning data are processed as a data block; wherein the value of m is [1, M], and M is the number of lines of zero scanning imaging;

[0011] Specifically, when the number of image data lines generated by the real-time scanning imaging is less than m lines, the imaging displayed in real time is image data without noise subtraction;

[0012] When the image data generated by the real-time scanning imaging is m rows, noise reduction is started on the data block consisting of the m rows of image data, and the m rows of image data after noise reduction are updated to the 1st to mth rows of image data;

[0013] Thereafter, each time a new line of image data is generated by the real-time scanning imaging, it is merged with the m-1 lines of image data before the line to form a data block of m lines for noise subtraction, and the image data after noise subtraction is used to update the previous m lines of image data including the current line; this process is repeated until the real-time scanning reaches the number of lines M.

[0014] Preferably, the zero scan noise template establishment specifically includes:

[0015] Zero scan imaging: Atomic force microscope performs zero scan imaging to obtain zero scan data;

[0016] Zero scan frequency domain transformation, processing the zero scan data to obtain zero scan frequency domain signal data;

[0017] Determine a noise segmentation threshold value, and determine the noise segmentation threshold value of the zero-scan frequency domain signal data;

[0018] The noise subtraction template is generated by determining all noise frequency bands in the zero-scan frequency domain signal data according to the noise segmentation threshold to form a noise subtraction template.

[0019] Preferably, the real-time scanning imaging noise suppression specifically includes:

[0020] Real-time scanning and imaging: Atomic force microscope performs real-time scanning and imaging to obtain real-time scanning data;

[0021] Real-time scanning frequency domain transformation, processing the real-time scanning data to obtain real-time scanning frequency domain signal data;

[0022] Noise subtraction, using the noise subtraction template to perform noise subtraction on the real-time scanning frequency domain signal data;

[0023] Real-time scanning time domain transformation processes the denoised real-time scanning frequency domain signal data, converts it into a real-time scanning time domain signal, and performs real-time imaging output.

[0024] Preferably, the zero scan imaging specifically includes:

[0025] Zero scan data storage, the atomic force microscope performs zero scan imaging, wherein each frame of zero scan data is stored as two images: a trace image and a retrace image;

[0026] Zero scan image reorganization, reorganizing the Trace image and the Retrace image to obtain a reorganized image, in which the Trace image and the Retrace image correspond to each other vertically and one by one;

[0027] The reconstructed image is unfolded to be a one-dimensional time series according to the time sequence of data generation.

[0028] Preferably, the specific method of zero-scan image reconstruction is:

[0029] For the Trace image and Retrace image with a size of M rows and N columns, the xth row of the Trace image is used as the 2x-1th row of the reconstructed image, and the xth row of the Retrace image is used as the 2xth row of the reconstructed image, thereby obtaining a reconstructed image with 2M rows and N columns.

[0030] Preferably, the specific method of unfolding the recombined image is:

[0031] The recombined image is extracted and spliced ​​in the order of odd-numbered rows from left to right and even-numbered rows from right to left.

[0032] Preferably, the real-time scanning imaging specifically includes:

[0033] Real-time scanning data storage, the atomic force microscope performs real-time scanning imaging, wherein each frame of real-time scanning data is stored as two images: a Trace real-time image and a Retrace real-time image;

[0034] Real-time scanning image reorganization, reorganizing the Trace real-time image and the Retrace real-time image to obtain a real-time reorganized image, in which the Trace image and the Retrace image correspond to each other one by one;

[0035] The real-time reconstructed image is unfolded to be a one-dimensional time series according to the time sequence of data generation.

[0036] Preferably, the specific method of real-time scanning image reorganization is:

[0037] For the Trace real-time image and the Retrace real-time image with a size of m rows and N columns, the xth row of the Trace real-time image is used as the 2x-1th row of the real-time reconstructed image, and the xth row of the Retrace real-time image is used as the 2xth row of the real-time reconstructed image, thereby obtaining a real-time reconstructed image with 2m rows and N columns;

[0038] The value range of m is [1, M].

[0039] Preferably, the specific method of real-time reconstructed image expansion is:

[0040] The real-time reconstructed image is extracted and spliced ​​in the order of odd-numbered lines from left to right and even-numbered lines from right to left.

[0041] Preferably, the real-time scanning time domain transformation specifically includes:

[0042] Processing the denoised real-time scanning frequency domain signal data and converting it into a real-time scanning time domain signal;

[0043] Reconstructing the real-time scanning time domain signal into a two-dimensional image;

[0044] Split the reconstructed two-dimensional image into a denoised Trace real-time image and a Retrace real-time image;

[0045] The denoised Retrace real-time image is mirrored left and right.

[0046] Preferably, the noise subtraction specifically includes:

[0047] According to all the frequency points in each noise frequency band of the noise subtraction template, the data of the corresponding frequency point in the real-time scanning frequency domain signal data is processed as follows to obtain the frequency domain denoised data of the frequency point:

[0048] y_amp[k]=|y_real[k]|-f*|y_zero[k]|

[0049] y_theta[k]=arg(y_real[k])

[0050] y_dn[k]=y_amp[k]*exp(y_theta[k]*i)

[0051] Among them, y_real[k] and y_zero[k] are the real-time scan frequency domain value and zero scan complex frequency domain value of frequency point k respectively; |.| represents the modulus of the complex number, arg(.) represents the argument of the complex number; f is a positive real number denoising intensity factor, which is used to adjust the intensity of noise signal subtraction; when performing noise subtraction on complex frequency domain data, only its modulus value is subtracted to obtain the denoised modulus value y_amp[k] of frequency point k, while its argument y_theta[k] remains unchanged from the original real-time scan data; y_dn[k] is the complex value of frequency point k after noise subtraction, where exp(.) represents exponential operation and i is the imaginary unit.

[0052] Preferably, the noise segmentation threshold determination specifically includes:

[0053] Performing window mean filtering on the zero scan frequency domain signal data;

[0054] By means of a homogenization method, the zero-scan frequency domain signal data after window mean filtering is transformed into the interval of [0, 1];

[0055] Draw a cumulative histogram of a preset classification Y according to the zero-scan frequency domain signal data after the normalization;

[0056] According to the noise segmentation threshold percentile p, the noise segmentation threshold position THD in the cumulative histogram is determined:

[0057] THD=FFT_L*p

[0058] Wherein, FFT_L is the length of the zero scan frequency domain signal data;

[0059] Starting from the lowest level in the cumulative histogram, find the first level where the cumulative frequency is greater than or equal to THD, which is s, and calculate the noise segmentation threshold SPLIT_AMP:

[0060] SPLIT_AMP=s / Y*FFT_MAX

[0061] Wherein, FFT_MAX is the maximum value of the zero-scan frequency domain signal data.

[0062] Preferably, the noise subtraction template generation specifically includes:

[0063] The zero scan frequency domain signal data is segmented based on the noise segmentation threshold, and the frequency points whose values ​​are greater than or equal to the noise segmentation threshold are marked as possible noise frequency points, and the frequency points whose values ​​are less than the noise segmentation threshold are marked as non-noise frequency points, to obtain a segmentation result;

[0064] Observe one by one from the first frequency point to determine the entire noise frequency band of the zero-scan frequency domain signal data.

[0065] Preferably, the steps of obtaining the segmentation result and determining all noise frequency bands of the zero-scan frequency domain signal data further include:

[0066] The discrete noise frequency points in the segmentation result are closed connected with a preset window size CON_SIZE, and the specific method is as follows:

[0067] Observe one by one from the first frequency point. For a frequency point marked as a possible noise frequency point, if there are CON_SIZE subsequent frequency points marked as possible noise frequency points, all the frequency points between the two will be re-marked as possible noise frequency points.

[0068] According to a second aspect of the present invention, there is provided a real-time control system for atomic force microscope imaging noise, comprising:

[0069] A zero scan noise template establishment device is used to process zero scan data formed by zero scan imaging of an atomic force microscope to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary;

[0070] The real-time imaging noise suppression device is used to perform noise subtraction using the noise subtraction template during the real-time scanning imaging process of the atomic force microscope.

[0071] Preferably, the zero scan noise template establishing device specifically comprises:

[0072] Zero scan imaging module, used for atomic force microscope to perform zero scan imaging and obtain zero scan data;

[0073] A frequency domain transformation module, used for processing the zero scan data to obtain zero scan frequency domain signal data;

[0074] A noise segmentation threshold determination module, used to determine the noise segmentation threshold of the zero-scan frequency domain signal data;

[0075] The noise subtraction template generating module is used to determine all noise frequency bands in the zero-scan frequency domain signal data according to the noise segmentation threshold to form a noise subtraction template.

[0076] Preferably, the real-time imaging noise suppression device specifically comprises:

[0077] Real-time scanning and imaging module, used for real-time scanning and imaging of atomic force microscope to obtain real-time scanning data;

[0078] A real-time scanning frequency domain conversion module is used to process the real-time scanning data to obtain real-time scanning frequency domain signal data;

[0079] A noise subtraction module, used to use the noise subtraction template to perform noise subtraction on the real-time scanning frequency domain signal data;

[0080] The real-time scanning time domain conversion module is used to process the real-time scanning frequency domain signal data after denoising and convert it into a real-time scanning time domain signal.

[0081] Preferably, the zero-scan imaging module specifically includes:

[0082] A zero scan data storage unit, used for the atomic force microscope to perform zero scan imaging, wherein each frame of zero scan data is stored as two images: a trace image and a retrace image;

[0083] A zero scan image recombining unit, used for recombining the Trace image and the Retrace image to obtain a recombined image, in which the Trace image and the Retrace image correspond to each other vertically and one by one;

[0084] The recombined image expansion unit is used to expand the recombined image into a one-dimensional time series according to the time sequence of data generation.

[0085] Preferably, the real-time scanning imaging module specifically includes:

[0086] A real-time scanning data storage unit, used for the atomic force microscope to perform real-time scanning imaging, wherein each frame of real-time scanning data is stored as two images: a Trace real-time image and a Retrace real-time image;

[0087] A real-time scanning image recombining unit, used for recombining the Trace real-time image and the Retrace real-time image to obtain a real-time recombined image, in which the Trace image and the Retrace image correspond to each other vertically and one by one;

[0088] The real-time reconstructed image expansion unit is used to expand the real-time reconstructed image into a one-dimensional time series according to the time sequence of data generation.

[0089] Preferably, the noise segmentation threshold determination module specifically includes:

[0090] A window mean filtering unit, used for performing window mean filtering on the zero scan frequency domain signal data;

[0091] A normalization unit, used for transforming the zero-scan frequency domain signal data after window mean filtering into the interval of [0, 1] by a normalization method;

[0092] The noise segmentation threshold position obtaining unit draws a cumulative histogram of a preset classification Y according to the zero-scan frequency domain signal data after the normalization;

[0093] According to the noise segmentation threshold percentile p, the noise segmentation threshold position THD in the cumulative histogram is determined:

[0094] THD=FFT_L*p

[0095] Wherein, FFT_L is the length of the zero scan frequency domain signal data;

[0096] The noise segmentation threshold obtaining unit is used to start from the lowest level in the cumulative histogram, find the classification number s where the cumulative frequency is greater than or equal to THD for the first time, and calculate the noise segmentation threshold SPLIT_AMP:

[0097] SPLIT_AMP=s / Y*FFT_MAX

[0098] Wherein, FFT_MAX is the maximum value of the zero-scan frequency domain signal data.

[0099] Preferably, the noise subtraction template generation module specifically includes:

[0100] a segmentation result obtaining unit, configured to segment the zero scan frequency domain signal data based on the noise segmentation threshold, mark the frequency points whose values ​​are greater than or equal to the noise segmentation threshold as possible noise frequency points, and mark the frequency points whose values ​​are less than the noise segmentation threshold as non-noise frequency points, to obtain a segmentation result;

[0101] The total noise frequency band obtaining unit is used to observe one by one from the first frequency point to determine the total noise frequency band of the zero scan frequency domain signal data.

[0102] Preferably, the noise subtraction template generation module further includes:

[0103] The closed connection unit is used to close the discrete noise frequency points in the segmentation result with a preset window size CON_SIZE, specifically used to:

[0104] Observe one by one from the first frequency point. For a frequency point marked as a possible noise frequency point, if there are CON_SIZE subsequent frequency points marked as possible noise frequency points, all the frequency points between the two will be re-marked as possible noise frequency points.

[0105] According to a third aspect of the present invention, there is provided an electronic device, comprising:

[0106] processor;

[0107] and, a memory for storing processor-executable instructions;

[0108] The processor implements the steps in any of the above methods by running the executable instructions.

[0109] According to a fourth aspect of the present invention, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the computer program implements the steps in any one of the above methods when executed by a processor.

[0110] The present invention provides a real-time control method and system for atomic force microscope imaging noise. The method processes zero scan data formed in the zero scan imaging process of the atomic force microscope to obtain all noise frequency bands of the zero scan data, and forms a noise subtraction template to suppress real-time imaging noise. Since the noise subtraction template is obtained based on the current environment of the atomic force microscope, it can cope with the characteristics of complex noise and vibration sources, rich frequency spectrum, strong time-varying, etc.; the problem that passive vibration isolation means in the prior art are difficult to achieve ultra-wide frequency spectrum noise suppression, and active vibration isolation means are high in cost and limited in load capacity is solved.

[0111] In addition, the real-time control method and system for atomic force microscope imaging noise provided by the present invention, since the noise subtraction template is obtained for the current environment of the atomic force microscope, it has a good weakening effect on all vibration and noise sources in the current environment, and also has a strong weakening effect on the acoustic wave energy coupled through space, which can further improve the imaging effect of the atomic force microscope.

[0112] In an optional solution of the present invention, m consecutive lines of real-time scanned data are treated as a data block for denoising, and the output is updated in real time, thus saving the waiting time for real-time output; in addition, each time a new line of data is generated after m lines, it is merged with the m-1 lines of data before the line to form a data block for denoising, and output in real time, thus ensuring the continuity of the real-time output and further saving the waiting time for real-time output.

[0113] In an optional solution of the present invention, the two-dimensional image composed of the Trace image and the Retrace image is expanded into a one-dimensional time series, and the denoising processes of the Trace image and the Retrace image are integrated together, which simplifies the denoising process and saves denoising time.

[0114] In an optional solution of the present invention, in the process of establishing the noise subtraction template, discrete noise frequency points are closed and connected to form a noise frequency band, which further improves the denoising effect and saves denoising time. BRIEF DESCRIPTION OF THE DRAWINGS

[0115] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0116] Figure 1 A flowchart of a method for real-time control of atomic force microscope imaging noise according to an embodiment of the present invention;

[0117] Figure 2 A flowchart of establishing a zero scan noise template according to a preferred embodiment of the present invention;

[0118] Figure 3 A flowchart of real-time imaging noise suppression according to a preferred embodiment of the present invention;

[0119] Figure 4 A schematic diagram of the reorganization of a Trace image and a Retrace image according to a preferred embodiment of the present invention;

[0120] Figure 5 A schematic diagram of a reconstructed image expanded into a one-dimensional time series according to a preferred embodiment of the present invention;

[0121] Figure 6 A schematic diagram of reconstructing a two-dimensional image from a real-time scanning time domain signal according to a preferred embodiment of the present invention;

[0122] Figure 7 It is a schematic diagram of image splitting of a two-dimensional image and left-right mirroring of a Retrace image according to a preferred embodiment of the present invention;

[0123] Figure 8 A schematic diagram of a real-time control system for atomic force microscope imaging noise according to an embodiment of the present invention;

[0124] Fig. 9 A schematic diagram of a zero scan noise template establishing device according to a preferred embodiment of the present invention;

[0125] Fig.10 A schematic diagram of a real-time imaging noise suppression device according to a preferred embodiment of the present invention;

[0126] Fig.11 is a schematic diagram of a zero-scan imaging module according to a preferred embodiment of the present invention;

[0127] Fig.12 is a schematic diagram of a real-time scanning imaging module according to a preferred embodiment of the present invention;

[0128] Fig.13 is a schematic diagram of an electronic device according to an embodiment of the present invention;

[0129] Description of reference numerals:

[0130] 1- Zero scan noise template establishment device,

[0131] 11- Zero scan imaging module,

[0132] 111-zero scan data storage unit,

[0133] 112-zero scan image reconstruction unit,

[0134] 113-reorganization image expansion unit;

[0135] 12-Frequency domain transformation module,

[0136] 13- Noise segmentation threshold determination module,

[0137] 14- Noise subtraction template generation module;

[0138] 2- Real-time imaging noise suppression device,

[0139] 21- Real-time scanning imaging module,

[0140] 211-Real-time scanning data storage unit,

[0141] 212-Real-time scanning image reconstruction unit,

[0142] 213-Real-time reorganization image development unit;

[0143] 22- Real-time scanning frequency domain transformation module,

[0144] 23- Noise Subtraction Module,

[0145] 24- Real-time scanning time domain transformation module;

[0146] 31- Processor,

[0147] 32-internal bus,

[0148] 33-Memory,

[0149] 34-Memory. DETAILED DESCRIPTION

[0150] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0151] In the description of the specification of the present invention, it is necessary to understand that the orientation or position relationship indicated by the terms "upper part", "lower part", "upper end", "lower end", "lower surface", "upper surface", etc. is based on the orientation or position relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0152] In the description of the present specification, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0153] In the description of the present invention, "plurality" means a plurality, such as two, three, four, etc., unless otherwise clearly and specifically defined.

[0154] In the description of the present invention, unless otherwise clearly specified and limited, the term "connection" and other terms should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0155] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0156] In one embodiment, a method for real-time control of atomic force microscope imaging noise is provided. Figure 1 , which includes:

[0157] S1: zero scan noise template establishment, processing the zero scan data formed by the zero scan imaging of the atomic force microscope to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary (i.e., "zero motion" state);

[0158] S2: Real-time scanning imaging noise suppression. During the real-time scanning imaging process of the atomic force microscope, noise subtraction template is used to perform noise subtraction.

[0159] Preferably, all measurement parameters (scanning size, resolution, scanning speed, etc.) used in the zero scanning mode are consistent with the parameters used in the real-time scanning imaging.

[0160] In one embodiment, when real-time scanning imaging noise suppression is performed, continuous m lines of real-time scanning data are processed as a data block; wherein the value of m is [1, M], M is the number of lines of zero scanning imaging, that is, M is the maximum number of lines.

[0161] Specifically, when the number of image data lines generated by real-time scanning imaging is less than m lines, the imaging displayed in real time is image data without noise subtraction;

[0162] When the image data generated by real-time scanning imaging is m rows, noise subtraction is started on the data block consisting of the m rows of image data, and the m rows of image data after noise subtraction are updated to the 1st row to the mth row of image data;

[0163] After that, every time a new line of image data is generated by real-time scanning imaging, it is merged with the m-1 lines of image data before the line to form a data block of m lines for noise subtraction, and the image data after noise subtraction is used to update the previous m lines of image data including the current line; the process is repeated until the real-time scanning reaches the maximum number of lines M.

[0164] By adopting the above-mentioned data block method for denoising, the output can be updated in real time, saving the output waiting time; and each time a new row of data is generated after m rows, it is merged with the m-1 rows of data before the row to form a data block for denoising and real-time output, which ensures the continuity of real-time output and further saves the waiting time for real-time output.

[0165] It should be noted that in the above embodiment, it is a preferred implementation to process m rows as a data block. In different embodiments, it is also possible to scan in real time until the maximum number of rows M is reached and then perform denoising processing uniformly. In addition, in the above embodiment, it is also a preferred implementation to combine each new row of data generated after row m with the m-1 rows of data before the row to form a data block for denoising processing. In different embodiments, it is also possible to perform denoising processing once for every m rows, that is, denoising is performed once for rows 1-m, denoising is performed once for rows m+1-2m, and so on.

[0166] In one embodiment, please refer to Figure 2 , the zero scan noise template establishment specifically includes:

[0167] S11: Zero scan imaging, the atomic force microscope performs zero scan imaging to obtain zero scan data;

[0168] S12: zero scan frequency domain transformation, processing the zero scan data, which may be a fast Fourier transform (FFT), to obtain zero scan frequency domain signal data;

[0169] S13: Determine the noise segmentation threshold, determine the noise segmentation threshold of the zero scan frequency domain signal data;

[0170] S14: generating a noise subtraction template, determining all noise frequency bands in the zero-scan frequency domain signal data according to the noise segmentation threshold, and forming a noise subtraction template.

[0171] In one embodiment, please refer to Figure 3 , real-time scanning imaging noise suppression specifically includes:

[0172] S21: Real-time scanning imaging, the atomic force microscope performs real-time scanning imaging to obtain real-time scanning data;

[0173] S22: Real-time scanning frequency domain transformation, processing the real-time scanning data, which can also be a fast Fourier transform, to obtain real-time scanning frequency domain signal data;

[0174] S23: noise subtraction, using a noise subtraction template to perform noise subtraction on the real-time scanning frequency domain signal data;

[0175] S24: Real-time scanning time domain transformation, processing the denoised real-time scanning frequency domain signal data, converting it into a real-time scanning time domain signal, and performing real-time imaging output.

[0176] In one embodiment, zero scan imaging specifically includes:

[0177] Zero-scan data storage,AFM performs zero-scan imaging, where each frame of zero-scan data is stored as two images: Trace image and Retrace image;

[0178] Zero scan image reorganization, reorganize the Trace image and Retrace image to obtain the reorganized image, please refer to Figure 4 , in the reconstructed image, the Trace image and the Retrace image correspond one to one up and down;

[0179] The reconstructed image is unfolded to be a one-dimensional time series according to the time sequence of data generation.

[0180] In one embodiment, the specific method of zero-scan image reconstruction is:

[0181] For a Trace image and a Retrace image with a size of M rows and N columns, the xth row of the Trace image is used as the 2x-1th row of the reconstructed image, and the xth row of the Retrace image is used as the 2xth row of the reconstructed image, thereby obtaining a reconstructed image with 2M rows and N columns. Please refer to Figure 4 .

[0182] In one embodiment, the specific method of reorganizing the image is as follows:

[0183] Extract and splice the reconstructed image in the order of odd rows from left to right and even rows from right to left. Please refer to Figure 5 .

[0184] In one embodiment, the real-time scanning imaging specifically includes:

[0185] Real-time scanning data storage, the atomic force microscope performs real-time scanning imaging, where each frame of real-time scanning data is stored as two images: Trace real-time image and Retrace real-time image;

[0186] Real-time scanning image reorganization, reorganize the Trace real-time image and the Retrace real-time image to obtain a real-time reorganized image, which is similar to the repetition method in zero-scan imaging. Please refer to Figure 4 , in the real-time reconstructed image, the Trace image and the Retrace image correspond one to one up and down;

[0187] The real-time reconstructed image is unfolded to be a one-dimensional time series according to the time sequence of data generation.

[0188] In one embodiment, the specific method of real-time scanning image reorganization is:

[0189] For a Trace real-time image and a Retrace real-time image with a size of m rows and N columns, the xth row of the Trace real-time image is used as the 2x-1th row of the real-time reconstructed image, and the xth row of the Retrace real-time image is used as the 2xth row of the real-time reconstructed image, thereby obtaining a real-time reconstructed image with 2m rows and N columns;

[0190] The value range of m is [1, M].

[0191] In the above embodiment, m rows are used as a data block for denoising, which is described in the above embodiment. Of course, in different embodiments, if m rows are not used as a data block for processing, but M rows are scanned in real time before processing, the reorganization process is also for the Trace real-time image and Retrace real-time image of M rows and N columns.

[0192] In one embodiment, the specific method of real-time reorganization image expansion is:

[0193] Extract and splice the real-time reconstructed image in the order of odd rows from left to right and even rows from right to left, which is similar to the expansion method of zero-scan reconstructed image. Please refer to Figure 5 .

[0194] It should be noted that, in different embodiments, whether it is zero scanning or real-time scanning, the method of expanding the reconstructed image is not necessarily the above-mentioned odd rows from left to right and even rows from right to left, and other methods can also be used, as long as the zero scanning and real-time scanning expansion processes follow the same rules and the denoising positions correspond.

[0195] In one embodiment, the real-time scanning time domain transformation specifically includes:

[0196] The denoised real-time scanning frequency domain signal data can be processed by inverse fast Fourier transform (IFFT) to convert it into a real-time scanning time domain signal, which is a one-dimensional sequence. If the above m rows are used as a data block, the length of the one-dimensional sequence here is 2×m×N;

[0197] Reconstruct the real-time scanning time domain signal into a two-dimensional image. Specifically, if the above size is taken as an example, it can be: starting from the first data, every N data is used as a row of the two-dimensional image, please refer to Figure 6 ;

[0198] Split the reconstructed 2D image into the denoised Trace real-time image and the Retrace real-time image. Please refer to Figure 7 Specifically, the (x / 2+1)th row of the image can be used as the xth row of the Trace real-time image, and the (x / 2+2th row can be used as the xth row of the Retrace real-time image;

[0199] To mirror the denoised Retrace real-time image to the left and right, please refer to Figure 7Specifically, the nth point of each row of data can be relocated to the position of the (N-n+1)th point; because the data here is expanded in the order of odd rows from left to right and even rows from right to left, the Retrace real-time image needs to be mirrored left and right. If the expansion method followed is different, this step can be omitted, or it needs to be changed according to actual needs.

[0200] In one embodiment, the noise subtraction specifically includes:

[0201] By comparing all the frequency points in each noise frequency band of the noise subtraction template, we can start from the lowest frequency point and process the data of the corresponding frequency point in the real-time scanning frequency domain signal data as follows to obtain the frequency domain denoising data of the frequency point:

[0202] y_amp[k]=|y_real[k]|-f*|y_zero[k]|

[0203] y_theta[k]=arg(y_real[k])

[0204] y_dn[k]=y_amp[k]*exp(y_theta[k]*i)

[0205] Among them, y_real[k] and y_zero[k] are the real-time scan frequency domain value and zero scan complex frequency domain value of frequency point k respectively; |.| represents the modulus of the complex number, arg(.) represents the argument of the complex number; f is a positive real number denoising intensity factor, which is used to adjust the intensity of noise signal subtraction; when performing noise subtraction on complex frequency domain data, only its modulus value is subtracted to obtain the denoised modulus value y_amp[k] of frequency point k, while its argument y_theta[k] remains unchanged from the original real-time scan data; y_dn[k] is the complex value of frequency point k after noise subtraction, where exp(.) represents exponential operation and i is the imaginary unit.

[0206] In one embodiment, determining the noise segmentation threshold specifically includes:

[0207] Performing window mean filtering on the zero scan frequency domain signal data; preferably, the window size may be the number of points n per row of the scanned image;

[0208] By means of a normalization method, the zero-scan frequency domain signal data after window mean filtering is transformed into the interval [0, 1]; preferably, the normalization method may adopt maximum and minimum value normalization;

[0209] Draw a cumulative histogram of a preset classification Y according to the zero-scan frequency domain signal data after the normalization;

[0210] According to the noise segmentation threshold percentile p, the noise segmentation threshold position THD in the cumulative histogram is determined:

[0211] THD=FFT_L*p

[0212] Wherein, FFT_L is the length of the zero-scan frequency domain signal data; preferably, the noise segmentation threshold percentile p can be a noise segmentation threshold percentile with a value between 80% and 90%;

[0213] Starting from the lowest level in the cumulative histogram, find the first level where the cumulative frequency is greater than or equal to THD, which is s, and calculate the noise segmentation threshold SPLIT_AMP:

[0214] SPLIT_AMP=s / Y*FFT_MAX

[0215] Wherein, FFT_MAX is the maximum value of the zero-scan frequency domain signal data.

[0216] Preferably, taking data of size M rows and N columns as an example, the preset level Y can be 10N. Of course, in different embodiments, other levels can also be used, and the level number can be an integer multiple of the number of columns N. The more levels there are, the higher the resolution determined by the noise segmentation threshold. The appropriate level number can be required as needed.

[0217] In one embodiment, generating a noise subtraction template specifically includes:

[0218] Based on the noise segmentation threshold, the zero scan frequency domain signal data is segmented, which can be a binary segmentation. The frequency points with values ​​greater than or equal to the noise segmentation threshold are marked as possible noise frequency points (which can be marked as "1"), and the frequency points with values ​​less than the noise segmentation threshold are marked as non-noise frequency points (which can be marked as "0"), and the segmentation results are obtained;

[0219] Observe one by one from the first frequency point to determine all the noise bands of the zero-scan frequency domain signal data. Specifically, the position where the value changes from "0" to "1" is the starting point Is of the noise band, and the position where the value changes from "1" to "0" is the ending point Ie of the noise band. The starting point and ending point of the noise band must appear in pairs and together constitute a description of a noise band. If a starting point is found during the observation and no ending point is found until the end of the frequency domain signal data, the last frequency point of the frequency domain signal data is used as the ending point of the noise band corresponding to the starting point. There may be one or more noise bands in the zero-scan frequency domain signal data, and the collection of all noise band descriptions constitutes a noise subtraction template.

[0220] In one embodiment, in order to further improve the denoising effect, obtaining the segmentation result and determining all noise frequency bands of the zero-scan frequency domain signal data further includes:

[0221] The discrete noise frequency points in the segmentation result are closed and connected with the preset window size CON_SIZE. The specific method is as follows:

[0222] Observe one by one from the first frequency point. For a frequency point marked as a possible noise frequency point ("1"), if there are CON_SIZE frequency points in the following frequency points that are marked as possible noise frequency points ("1"), then all the frequency points between the two will be re-marked as possible noise frequency points ("1"). CON_SIZE is an adjustable parameter, and the value range can be N to 2N.

[0223] In one embodiment, a real-time control system for atomic force microscope imaging noise is also provided. Figure 8 , which includes:

[0224] A zero scan noise template establishment device 1 is used to process zero scan data formed by zero scan imaging of an atomic force microscope to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary;

[0225] The real-time imaging noise suppression device 2 is used to perform noise subtraction using a noise subtraction template during the real-time scanning imaging process of the atomic force microscope.

[0226] In one embodiment, please refer to Fig. 9 , the zero scan noise template establishing device 1 specifically comprises:

[0227] The zero scan imaging module 11 is used for performing zero scan imaging with an atomic force microscope to obtain zero scan data;

[0228] The frequency domain transformation module 12 is used to process the zero scan data to obtain zero scan frequency domain signal data;

[0229] A noise segmentation threshold determination module 13 is used to determine the noise segmentation threshold of the zero-scan frequency domain signal data;

[0230] The noise subtraction template generating module 14 is used to determine all noise frequency bands in the zero-scan frequency domain signal data according to the noise segmentation threshold value to form a noise subtraction template.

[0231] In one embodiment, please refer to Fig.10 , the real-time imaging noise suppression device 2 specifically comprises:

[0232] The real-time scanning and imaging module 21 is used for performing real-time scanning and imaging with an atomic force microscope to obtain real-time scanning data;

[0233] The real-time scanning frequency domain conversion module 22 is used to process the real-time scanning data to obtain real-time scanning frequency domain signal data;

[0234] A noise subtraction module 23 is used to perform noise subtraction on real-time scanning frequency domain signal data using a noise subtraction template;

[0235] The real-time scanning time domain conversion module 24 is used to process the real-time scanning frequency domain signal data after denoising and convert it into a real-time scanning time domain signal.

[0236] In one embodiment, please refer to Fig.11 , the zero-scan imaging module 11 specifically includes:

[0237] A zero scan data storage unit 111 is used for performing zero scan imaging by an atomic force microscope, wherein each frame of zero scan data is stored as two images: a trace image and a retrace image;

[0238] The zero scan image recombining unit 112 is used to recombine the Trace image and the Retrace image to obtain a recombined image, in which the Trace image and the Retrace image correspond to each other vertically;

[0239] The reconstructed image expansion unit 113 is used to expand the reconstructed image into a one-dimensional time series according to the time sequence of data generation.

[0240] In one embodiment, please refer to Fig.12 The real-time scanning imaging module 21 specifically includes:

[0241] A real-time scanning data storage unit 211 is used for real-time scanning imaging by an atomic force microscope, wherein each frame of real-time scanning data is stored as two images: a Trace real-time image and a Retrace real-time image;

[0242] The real-time scanning image recombining unit 212 is used to recombine the Trace real-time image and the Retrace real-time image to obtain a real-time recombined image, in which the Trace image and the Retrace image correspond to each other vertically;

[0243] The real-time reconstructed image expansion unit 213 is used to expand the real-time reconstructed image into a one-dimensional time series according to the time sequence of data generation.

[0244] In one embodiment, the noise segmentation threshold determination module specifically includes:

[0245] A window mean filtering unit, used for performing window mean filtering on zero scan frequency domain signal data;

[0246] A normalization unit, used for transforming the zero-scan frequency domain signal data after window mean filtering into the interval of [0, 1] by a normalization method;

[0247] The noise segmentation threshold position obtaining unit draws a cumulative histogram of a preset classification Y according to the zero-scan frequency domain signal data after the normalization;

[0248] According to the noise segmentation threshold percentile p, determine the noise segmentation threshold position THD in the cumulative histogram:

[0249] THD=FFT_L*p

[0250] Wherein, FFT_L is the length of the zero scan frequency domain signal data;

[0251] The noise segmentation threshold obtaining unit is used to start from the lowest level in the cumulative histogram, find the classification number s where the cumulative frequency is greater than or equal to THD for the first time, and calculate the noise segmentation threshold SPLIT_AMP:

[0252] SPLIT_AMP=s / Y*FFT_MAX

[0253] Wherein, FFT_MAX is the maximum value of the zero-scan frequency domain signal data.

[0254] In one embodiment, the noise subtraction template generation module specifically includes:

[0255] The segmentation result obtaining unit is used to segment the zero scan frequency domain signal data based on the noise segmentation threshold, mark the frequency points whose values ​​are greater than or equal to the noise segmentation threshold as possible noise frequency points, and mark the frequency points whose values ​​are less than the noise segmentation threshold as non-noise frequency points, so as to obtain the segmentation result;

[0256] The whole noise frequency band acquisition unit is used to observe one by one from the first frequency point to determine the whole noise frequency band of the zero scan frequency domain signal data

[0257] In one embodiment, the noise subtraction template generation module further includes:

[0258] The closed connection unit is used to close the discrete noise frequency points in the segmentation result with a preset window size CON_SIZE, specifically used for:

[0259] Observe one by one from the first frequency point. For a frequency point marked as a possible noise frequency point, if there are CON_SIZE subsequent frequency points marked as possible noise frequency points, all the frequency points between the two will be re-marked as possible noise frequency points.

[0260] In one embodiment, an electronic device is also provided, please refer to Fig.13. At the hardware level, the device includes a processor 31, an internal bus 32, a memory 33 and a storage 34, and of course may also include hardware required for other services. One or more embodiments of the present invention can be implemented based on software, such as the processor 31 reading the corresponding computer program from the storage 34 into the memory 33 and then running it. Of course, in addition to software implementation, one or more embodiments of the present invention do not exclude other implementation methods, such as logic devices or a combination of software and hardware, etc., that is, the execution subject of the following processing flow is not limited to each logic unit, but can also be hardware or logic devices. Among them, the processor implements the steps in the method described in any of the above embodiments by running executable instructions, including:

[0261] A zero scan noise template is established, and the zero scan data formed by the zero scan imaging of the atomic force microscope is processed to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary;

[0262] Real-time scanning imaging noise suppression, during the real-time scanning imaging of the atomic force microscope, a noise subtraction template is used to perform noise subtraction.

[0263] In one embodiment, a storage medium is further provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the method described in any of the above embodiments are implemented, including:

[0264] A zero scan noise template is established, and the zero scan data formed by the zero scan imaging of the atomic force microscope is processed to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary;

[0265] Real-time scanning imaging noise suppression, during the real-time scanning imaging of the atomic force microscope, a noise subtraction template is used to perform noise subtraction.

[0266] Storage media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer-readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic disk storage, quantum memory, graphene-based storage media or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device.

[0267] In the description of this specification, the description with reference to the terms "an implementation", "an example", "a specific implementation process", "an example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0268] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A real-time control method for atomic force microscope imaging noise, characterized in that: include: A zero scan noise template is established, and the zero scan data formed by the zero scan imaging of the atomic force microscope is processed to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary; Real-time scanning imaging noise suppression: During the real-time scanning imaging process of the atomic force microscope, the noise subtraction template is used to perform noise subtraction.

2. The method for real-time control of atomic force microscope imaging noise according to claim 1, characterized in that: When suppressing the real-time scanning imaging noise, m consecutive lines of real-time scanning data are processed as a data block; wherein the value of m is [1, M], and M is the number of lines of zero scanning imaging; Specifically, when the number of image data lines generated by the real-time scanning imaging is less than m lines, the imaging displayed in real time is image data without noise subtraction; When the image data generated by the real-time scanning imaging is m rows, noise reduction is started on the data block consisting of the m rows of image data, and the m rows of image data after noise reduction are updated to the 1st to mth rows of image data; Thereafter, each time a new line of image data is generated by the real-time scanning imaging, it is merged with the m-1 lines of image data before the line to form a data block of m lines for noise subtraction, and the image data after noise subtraction is used to update the previous m lines of image data including the current line; this process is repeated until the real-time scanning reaches the number of lines M.

3. The real-time control method for atomic force microscope imaging noise according to claim 1, characterized in that: The zero scan noise template establishment specifically includes: Zero scan imaging: Atomic force microscope performs zero scan imaging to obtain zero scan data; Zero scan frequency domain transformation, processing the zero scan data to obtain zero scan frequency domain signal data; Determine a noise segmentation threshold value, and determine the noise segmentation threshold value of the zero-scan frequency domain signal data; The noise subtraction template is generated by determining all noise frequency bands in the zero-scan frequency domain signal data according to the noise segmentation threshold to form a noise subtraction template.

4. The method for real-time control of atomic force microscope imaging noise according to claim 3, characterized in that: The real-time scanning imaging noise suppression specifically includes: Real-time scanning and imaging: Atomic force microscope performs real-time scanning and imaging to obtain real-time scanning data; Real-time scanning frequency domain transformation, processing the real-time scanning data to obtain real-time scanning frequency domain signal data; Noise subtraction, using the noise subtraction template to perform noise subtraction on the real-time scanning frequency domain signal data; Real-time scanning time domain transformation processes the denoised real-time scanning frequency domain signal data, converts it into a real-time scanning time domain signal, and performs real-time imaging output.

5. The real-time control method for atomic force microscope imaging noise according to claim 4, characterized in that: The zero scan imaging specifically includes: Zero scan data storage, the atomic force microscope performs zero scan imaging, wherein each frame of zero scan data is stored as two images: a trace image and a retrace image; Zero scan image reorganization, reorganizing the Trace image and the Retrace image to obtain a reorganized image, in which the Trace image and the Retrace image correspond to each other vertically and one by one; The reconstructed image is unfolded to be a one-dimensional time series according to the time sequence of data generation.

6. The method for real-time control of atomic force microscope imaging noise according to claim 5, characterized in that: The specific method of zero scan image reconstruction is: For the Trace image and Retrace image with a size of M rows and N columns, the xth row of the Trace image is used as the 2x-1th row of the reconstructed image, and the xth row of the Retrace image is used as the 2xth row of the reconstructed image, thereby obtaining a reconstructed image with 2M rows and N columns.

7. The real-time control method for atomic force microscope imaging noise according to claim 6, characterized in that: The specific method of unfolding the recombined image is: The recombined image is extracted and spliced ​​in the order of odd-numbered rows from left to right and even-numbered rows from right to left.

8. The method for real-time control of atomic force microscope imaging noise according to claim 7, characterized in that: The real-time scanning imaging specifically includes: Real-time scanning data storage, the atomic force microscope performs real-time scanning imaging, wherein each frame of real-time scanning data is stored as two images: a Trace real-time image and a Retrace real-time image; Real-time scanning image reorganization, reorganizing the Trace real-time image and the Retrace real-time image to obtain a real-time reorganized image, in which the Trace image and the Retrace image correspond to each other one by one; The real-time reconstructed image is unfolded to be a one-dimensional time series according to the time sequence of data generation.

9. The real-time control method for atomic force microscope imaging noise according to claim 8, characterized in that: The specific method of real-time scanning image reorganization is: For the Trace real-time image and the Retrace real-time image with a size of m rows and N columns, the xth row of the Trace real-time image is used as the 2x-1th row of the real-time reconstructed image, and the xth row of the Retrace real-time image is used as the 2xth row of the real-time reconstructed image, thereby obtaining a real-time reconstructed image with 2m rows and N columns; The value range of m is [1, M].

10. The real-time control method for atomic force microscope imaging noise according to claim 9, characterized in that: The specific method of real-time recombinant image expansion is: The real-time reconstructed image is extracted and spliced ​​in the order of odd-numbered lines from left to right and even-numbered lines from right to left.

11. The method for real-time control of atomic force microscope imaging noise according to claim 10, characterized in that: The real-time scanning time domain transformation specifically includes: Processing the denoised real-time scanning frequency domain signal data and converting it into a real-time scanning time domain signal; Reconstructing the real-time scanning time domain signal into a two-dimensional image; Split the reconstructed two-dimensional image into a denoised Trace real-time image and a Retrace real-time image; The denoised Retrace real-time image is mirrored left and right.

12. The method for real-time control of atomic force microscope imaging noise according to claim 4, characterized in that: The noise subtraction specifically includes: According to all the frequency points in each noise frequency band of the noise subtraction template, the data of the corresponding frequency point in the real-time scanning frequency domain signal data is processed as follows to obtain the frequency domain denoised data of the frequency point: y_amp[k]=|y_real[k]|-f*|y_zero[k]| y_theta[k]=arg(y_real[k]) y_dn[k]=y_amp[k]*exp(y_theta[k]*i) Among them, y_real[k] and y_zero[k] are the real-time scan frequency domain value and zero scan complex frequency domain value of frequency point k respectively; |.| represents the modulus of the complex number, arg(.) represents the argument of the complex number; f is a positive real number denoising intensity factor, which is used to adjust the intensity of noise signal subtraction; when performing noise subtraction on complex frequency domain data, only its modulus value is subtracted to obtain the denoised modulus value y_amp[k] of frequency point k, while its argument y_theta[k] remains unchanged from the original real-time scan data; y_dn[k] is the complex value of frequency point k after noise subtraction, where exp(.) represents exponential operation and i is the imaginary unit.

13. The method for real-time control of atomic force microscope imaging noise according to any one of claims 3 to 12, characterized in that: The noise segmentation threshold determination specifically includes: Performing window mean filtering on the zero scan frequency domain signal data; By means of a homogenization method, the zero-scan frequency domain signal data after window mean filtering is transformed into the interval of [0, 1]; Draw a cumulative histogram of a preset classification Y according to the zero-scan frequency domain signal data after the normalization; According to the noise segmentation threshold percentile p, the noise segmentation threshold position THD in the cumulative histogram is determined: THD=FFT_L*p Wherein, FFT_L is the length of the zero scan frequency domain signal data; Starting from the lowest level in the cumulative histogram, find the first level where the cumulative frequency is greater than or equal to THD, which is s, and calculate the noise segmentation threshold SPLIT_AMP: SPLIT_AMP=s / Y*FFT_MAX Wherein, FFT_MAX is the maximum value of the zero-scan frequency domain signal data.

14. The method for real-time control of atomic force microscope imaging noise according to any one of claims 3 to 12, characterized in that: The noise subtraction template generation specifically includes: The zero scan frequency domain signal data is segmented based on the noise segmentation threshold, and the frequency points whose values ​​are greater than or equal to the noise segmentation threshold are marked as possible noise frequency points, and the frequency points whose values ​​are less than the noise segmentation threshold are marked as non-noise frequency points, to obtain a segmentation result; Observe one by one from the first frequency point to determine the entire noise frequency band of the zero-scan frequency domain signal data.

15. The real-time control method for atomic force microscope imaging noise according to claim 14, characterized in that: The step of obtaining the segmentation result and determining all noise frequency bands of the zero-scan frequency domain signal data further includes: The discrete noise frequency points in the segmentation result are closed connected with a preset window size CON_SIZE, and the specific method is as follows: Observe one by one from the first frequency point. For a frequency point marked as a possible noise frequency point, if there are CON_SIZE subsequent frequency points marked as possible noise frequency points, all the frequency points between the two will be re-marked as possible noise frequency points.

16. A real-time control system for atomic force microscope imaging noise, characterized in that: include: A zero scan noise template establishment device is used to process zero scan data formed by zero scan imaging of an atomic force microscope to obtain all noise frequency bands of the zero scan data to form a noise subtraction template; wherein, during the zero scan imaging process, all motion dimensions of the atomic force microscope used for zero scan imaging remain stationary; The real-time imaging noise suppression device is used to perform noise subtraction using the noise subtraction template during the real-time scanning imaging process of the atomic force microscope.

17. The real-time control system for atomic force microscope imaging noise according to claim 16, characterized in that: The zero scan noise template establishing device specifically comprises: Zero scan imaging module, used for atomic force microscope to perform zero scan imaging and obtain zero scan data; A frequency domain transformation module, used for processing the zero scan data to obtain zero scan frequency domain signal data; A noise segmentation threshold determination module, used to determine the noise segmentation threshold of the zero-scan frequency domain signal data; The noise subtraction template generating module is used to determine all noise frequency bands in the zero-scan frequency domain signal data according to the noise segmentation threshold to form a noise subtraction template.

18. The real-time control system for atomic force microscope imaging noise according to claim 17, characterized in that: The real-time imaging noise suppression device specifically comprises: Real-time scanning and imaging module, used for real-time scanning and imaging of atomic force microscope to obtain real-time scanning data; A real-time scanning frequency domain conversion module is used to process the real-time scanning data to obtain real-time scanning frequency domain signal data; A noise subtraction module, used to use the noise subtraction template to perform noise subtraction on the real-time scanning frequency domain signal data; The real-time scanning time domain conversion module is used to process the real-time scanning frequency domain signal data after denoising and convert it into a real-time scanning time domain signal.

19. The real-time control system for atomic force microscope imaging noise according to claim 18, characterized in that: The zero-scan imaging module specifically includes: A zero scan data storage unit, used for the atomic force microscope to perform zero scan imaging, wherein each frame of zero scan data is stored as two images: a trace image and a retrace image; A zero scan image recombining unit, used for recombining the Trace image and the Retrace image to obtain a recombined image, in which the Trace image and the Retrace image correspond to each other vertically and one by one; The recombined image expansion unit is used to expand the recombined image into a one-dimensional time series according to the time sequence of data generation.

20. The real-time control system for atomic force microscope imaging noise according to claim 19, characterized in that: The real-time scanning imaging module specifically includes: A real-time scanning data storage unit, used for the atomic force microscope to perform real-time scanning imaging, wherein each frame of real-time scanning data is stored as two images: a Trace real-time image and a Retrace real-time image; A real-time scanning image recombining unit, used for recombining the Trace real-time image and the Retrace real-time image to obtain a real-time recombined image, in which the Trace image and the Retrace image correspond to each other vertically and one by one; The real-time reconstructed image expansion unit is used to expand the real-time reconstructed image into a one-dimensional time series according to the time sequence of data generation.

21. The real-time control system for atomic force microscope imaging noise according to any one of claims 17 to 20, characterized in that: The noise segmentation threshold determination module specifically includes: A window mean filtering unit, used for performing window mean filtering on the zero scan frequency domain signal data; A normalization unit, used for transforming the zero-scan frequency domain signal data after window mean filtering into the interval of [0, 1] by a normalization method; The noise segmentation threshold position obtaining unit draws a cumulative histogram of a preset classification Y according to the zero-scan frequency domain signal data after the normalization; According to the noise segmentation threshold percentile p, the noise segmentation threshold position THD in the cumulative histogram is determined: THD=FFT_L*p Wherein, FFT_L is the length of the zero scan frequency domain signal data; The noise segmentation threshold obtaining unit is used to start from the lowest level in the cumulative histogram, find the classification number s where the cumulative frequency is greater than or equal to THD for the first time, and calculate the noise segmentation threshold SPLIT_AMP: SPLIT_AMP=s / Y*FFT_MAX Wherein, FFT_MAX is the maximum value of the zero-scan frequency domain signal data.

22. The real-time control system for atomic force microscope imaging noise according to any one of claims 17 to 20, characterized in that: The noise subtraction template generation module specifically includes: a segmentation result obtaining unit, configured to segment the zero scan frequency domain signal data based on the noise segmentation threshold, mark the frequency points whose values ​​are greater than or equal to the noise segmentation threshold as possible noise frequency points, and mark the frequency points whose values ​​are less than the noise segmentation threshold as non-noise frequency points, to obtain a segmentation result; The total noise frequency band obtaining unit is used to observe one by one from the first frequency point to determine the total noise frequency band of the zero scan frequency domain signal data.

23. The real-time control system for atomic force microscope imaging noise according to claim 22, characterized in that: The noise subtraction template generation module also includes: The closed connection unit is used to close the discrete noise frequency points in the segmentation result with a preset window size CON_SIZE, specifically used to: Observe one by one from the first frequency point. For a frequency point marked as a possible noise frequency point, if there are CON_SIZE subsequent frequency points marked as possible noise frequency points, all the frequency points between the two will be re-marked as possible noise frequency points.

24. An electronic device, characterized in that: include: processor; and, a memory for storing processor-executable instructions; The processor implements the steps in the method of any one of claims 1-15 by running the executable instructions.

25. A computer-readable storage medium, characterized in that: A computer program is stored thereon, and when the computer program is executed by a processor, the steps in the method according to any one of claims 1 to 15 are implemented.

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