Three-dimensional laminated imaging method and device, terminal and storage medium
By generating parallel optical target spots containing multiple incident angles and controlling sample translation, and reconstructing the three-dimensional image with gradient descent method, the problem of long data acquisition time in three-dimensional stacking imaging is solved, and efficient three-dimensional image reconstruction is achieved.
Patent Information
- Application Number
- CN202411130745.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-16
- Publication Date
- 2024-12-31
AI Technical Summary
In the existing three-dimensional stacked imaging technology, the data acquisition time of three-dimensional scanning coherent diffraction imaging is relatively long, and diffraction patterns at multiple angles need to be collected to achieve accurate three-dimensional image reconstruction.
By acquiring optical component parameters, configuring the target optical component and deploying the light source, target optical component and two-dimensional detector along the optical path, generating parallel optical target spots containing multiple incident angles, controlling sample translation to collect multiple diffraction signals, using gradient descent Three-dimensional images of samples were reconstructed.
It effectively reduces data acquisition time, avoids multi-angle scanning of rotating samples, improves data acquisition efficiency, and reduces sample radiation damage.
Smart Images
Figure CN119228988A_ABST
Abstract
Description
Technical Field
[0001] The present invention relates to the field of three-dimensional reconstruction technology, and in particular to a three-dimensional stacked imaging method, device, terminal and storage medium. Background Art
[0002] As an ultra-high resolution three-dimensional imaging method, three-dimensional stacking imaging is an important method for studying the three-dimensional microscopic morphology of samples. Three-dimensional imaging methods based on stacking imaging mainly include stacking-CT imaging (PXCT) and stacking-tomography (PyXL). Both stacking-CT imaging (PXCT) and stacking-tomography (PyXL) adopt a combination of two-dimensional stacking and three-dimensional imaging, and need to obtain scanning diffraction patterns at dozens of different angles by rotating the sample. The reconstruction process of the three-dimensional imaging method based on stacking imaging is divided into two steps: first, for each specific angle, the two-dimensional projection image of the sample can be reconstructed by the phase recovery algorithm of two-dimensional stacking imaging. Then, the two-dimensional projection images at different angles are processed using the CT reconstruction algorithm to reconstruct the three-dimensional structural information of the sample. In order to accurately reconstruct the three-dimensional image, this method needs to collect diffraction patterns at enough angles, which makes the data acquisition time of three-dimensional scanning coherent diffraction imaging longer.
[0003] Therefore, the prior art has defects and needs to be improved and developed. Summary of the invention
[0004] The technical problem to be solved by the present invention is to provide a three-dimensional stacked imaging method, device, terminal and storage medium in view of the above-mentioned defects of the prior art, aiming to solve the problem of long data acquisition time in three-dimensional scanning coherent diffraction imaging in the prior art.
[0005] The technical solution adopted by the present invention to solve the technical problem is as follows:
[0006] In a first aspect, an embodiment of the present invention provides a three-dimensional stacked imaging method, the method comprising:
[0007] Acquire preset optical element parameters, and configure the target optical element using the optical element parameters;
[0008] A light source, a target optical element, a sample, and a two-dimensional detector are sequentially deployed along the optical path;
[0009] When the light source emits light, it is processed by the target optical element to generate a target light spot and irradiate the sample, and the sample is controlled to translate in a preset manner to obtain multiple diffraction signals of the sample, wherein the target light spot contains parallel light of multiple incident angles;
[0010] The two-dimensional detector is used to collect all the diffraction signals to generate a plurality of two-dimensional diffraction patterns, and the signal is reconstructed based on all the two-dimensional diffraction patterns using a gradient descent method to obtain a three-dimensional reconstructed image of the sample.
[0011] In one embodiment, the method for generating optical element parameters includes:
[0012] Acquire the preset light source wavelength and target resolution of the imaging system, and perform processing based on the light source wavelength and the target resolution to obtain the maximum diffraction angle of the target light spot;
[0013] The preset size of the target light spot is obtained, and preset software is used to perform inversion based on the maximum diffraction angle and the preset size to obtain optical element parameters.
[0014] In one embodiment, the preset size of the target light spot satisfies the Nyquist-Shannon sampling theorem, and the formula of the Nyquist-Shannon sampling theorem is: Where D represents the preset size, λ represents the wavelength of the light source, z represents the distance from the sample to the detector, and Δ d Represents the detector pixel size.
[0015] In one embodiment, the target resolution is any one of a lateral resolution and a depth resolution; the processing based on the light source wavelength and the target resolution to obtain the maximum diffraction angle of the target light spot includes:
[0016] If the target resolution is the lateral resolution, then the formula Obtain the maximum diffraction angle of the target light spot, where d x represents the lateral resolution, λ is the wavelength of the light source;
[0017] If the target resolution is depth resolution, then the formula Obtain the maximum diffraction angle of the target light spot, where d z represents the depth resolution, and λ is the wavelength of the light source.
[0018] In one embodiment, the step of reconstructing a signal based on all of the two-dimensional diffraction patterns using a gradient descent method to obtain three-dimensional image data of the sample includes:
[0019] Uniformly stratifying the sample according to the spatial coordinates of the sample to obtain a plurality of slices;
[0020] Acquire an initial probe function, a sample function of each slice layer, and a relative position vector between the sample and the target spot, and perform calculation based on the initial probe function, the sample function of the first slice layer, and the relative position vector to obtain an output wave function of the first slice layer;
[0021] Iteratively use the output wave function of the previous slice as the probe function of the current slice, and calculate the output wave function according to the sample function and probe function of the current slice, until the output wave function of the last slice is obtained;
[0022] The outgoing wave function of the last slice is propagated to a two-dimensional detector to obtain a simulated diffraction pattern;
[0023] Obtaining a preset initial wavefront function, comparing the simulated diffraction pattern with all the two-dimensional diffraction patterns, adjusting the initial wavefront function by a gradient descent method, and obtaining a second wavefront function;
[0024] Back-propagating the second wavefront function back to the sample plane to update the sample function of each slice layer, repeating the back-propagation and updating steps until a preset round, to obtain the final sample function of each slice layer;
[0025] The three-dimensional inversion processing is performed based on the final sample function of each slice layer to obtain a three-dimensional reconstructed image of the sample.
[0026] In one embodiment, the light source is visible light or X-rays.
[0027] In one embodiment, the target optical element is any one of a spatial light modulator, a refractive lens, a zone plate, a compound refractive index lens, a grating, and a crystal.
[0028] In a second aspect, an embodiment of the present invention further provides a three-dimensional stacked imaging device, comprising:
[0029] An element setting module is used to obtain preset optical element parameters and configure a target optical element using the optical element parameters;
[0030] A device deployment module, used to sequentially deploy a light source, a target optical element, a sample, and a two-dimensional detector along an optical path;
[0031] A signal generating module, which is used to generate a target light spot after the light source emits light, and irradiate the target light spot onto the sample after being processed by the target optical element, and control the sample to translate in a preset manner to obtain multiple diffraction signals of the sample;
[0032] The three-dimensional reconstruction module is used to collect all the diffraction signals using the two-dimensional detector to generate multiple two-dimensional diffraction patterns, and reconstruct the signals based on all the two-dimensional diffraction patterns using the gradient descent method to obtain a three-dimensional reconstructed image of the sample.
[0033] In a third aspect, an embodiment of the present invention further provides a terminal, comprising: a memory, a processor, and a three-dimensional stacked imaging program stored in the memory and executable on the processor, wherein the three-dimensional stacked imaging program implements the steps of the three-dimensional stacked imaging method as described above when executed by the processor.
[0034] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium storing a three-dimensional stacked imaging program, wherein the three-dimensional stacked imaging program can be executed to implement the steps of the three-dimensional stacked imaging method as described above.
[0035] Beneficial effects of the present invention: The present invention obtains optical element parameters and configures the target optical element using the optical element parameters; deploys the light source, target optical element, sample and two-dimensional detector in sequence along the light path; when the light source emits light, a target light spot is generated and irradiated onto the sample, and the sample is controlled to translate in a preset manner to obtain multiple diffraction signals of the sample, wherein the target light spot contains parallel light of multiple incident angles; and a three-dimensional reconstructed image of the sample is generated. The present invention generates a target light spot of parallel light containing multiple incident angles by using a target optical element, and controls the sample to translate in a preset manner, so that samples in different areas are irradiated by the target light spot in sequence, thereby generating multiple diffraction signals containing information of different parts of the sample, which can avoid rotating the sample to collect diffraction patterns at multiple angles, and effectively reduces the data acquisition time. BRIEF DESCRIPTION OF THE DRAWINGS
[0036] Figure 1 It is a flow chart of a preferred embodiment of the three-dimensional stacked imaging method in the present invention.
[0037] Figure 2 It is a schematic diagram of scanning samples of the three-dimensional stacked imaging method of the present invention.
[0038] Figure 3 It is a schematic diagram of a scanning sample of the stacked-CT imaging method of the present invention.
[0039] Figure 4 It is a schematic cross-sectional view of a sample scanned by light in the three-dimensional stacked imaging method of the present invention.
[0040] Figure 5 It is a functional principle block diagram of a preferred embodiment of the three-dimensional stacked imaging device in the present invention.
[0041] Figure 6 It is a terminal principle block diagram of the present invention. DETAILED DESCRIPTION
[0042] In order to make the purpose, technical solution and advantages of the present invention clearer and more specific, the present invention is further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.
[0043] As an ultra-high resolution three-dimensional imaging method, three-dimensional stacking imaging is an important method for studying the three-dimensional microscopic morphology of samples. At present, the three-dimensional imaging methods based on stacking imaging mainly include stacking-CT imaging (PXCT), stacking-tomography (PyXL) and other methods. Both of them use a combination of two-dimensional stacking and mature three-dimensional imaging, and need to rotate the sample to obtain dozens of scanning diffraction patterns at different angles. The reconstruction process of the three-dimensional imaging method based on stacking imaging is divided into two steps: first, for each specific angle, the two-dimensional projection image of the sample can be reconstructed by the phase recovery algorithm of two-dimensional stacking imaging. Then, the two-dimensional projection images at different angles are processed using the CT reconstruction algorithm to reconstruct the three-dimensional structural information of the sample. This method only realizes the two-dimensional reconstruction of the sample in the reconstruction of a single angle, and discards the depth information in the scanning diffraction data. In order to accurately reconstruct the three-dimensional image, this method needs to collect diffraction patterns at enough angles, which makes the data acquisition time of three-dimensional scanning coherent diffraction imaging longer.
[0044] In view of the above-mentioned defects of the prior art, the present invention provides a three-dimensional stacked imaging method, device, terminal and storage medium, the method comprising: obtaining optical element parameters, configuring the target optical element using the optical element parameters; sequentially deploying the light source, the target optical element, the sample and the two-dimensional detector along the optical path; when the light source emits light, a target light spot is generated and irradiated onto the sample, the sample is controlled to translate in a preset manner to obtain multiple diffraction signals of the sample, and the target light spot contains parallel light of multiple incident angles; and a three-dimensional reconstructed image of the sample is generated. The present invention generates a target light spot of parallel light containing multiple incident angles by using the target optical element, and controls the sample to translate in a preset manner, so that samples in different areas are sequentially irradiated by the target light spot, thereby generating multiple diffraction signals containing information of different parts of the sample, which can avoid rotating the sample to collect diffraction patterns at multiple angles, and effectively reduce the data acquisition time.
[0045] See also Figure 1 The three-dimensional stacked imaging method described in the embodiment of the present invention comprises the following steps:
[0046] Step S100: Obtain preset optical element parameters, and configure a target optical element using the optical element parameters.
[0047] Specifically, the target optical element is used to process light to generate a light spot that meets user needs. The optical element parameters are parameters corresponding to the target optical element, which are used to control the shape, size, position and intensity of the light spot. In the present invention, it is necessary to obtain the optical element parameters to configure the target optical element so that the target light spot can be generated after the light passes through the target optical element, and the target light spot is subsequently used to scan the sample to achieve three-dimensional reconstruction.
[0048] In one implementation, the method for generating optical element parameters includes:
[0049] Acquire the preset light source wavelength and target resolution of the imaging system, and perform processing based on the light source wavelength and the target resolution to obtain the maximum diffraction angle of the target light spot;
[0050] The preset size of the target light spot is obtained, and preset software is used to perform inversion based on the maximum diffraction angle and the preset size to obtain optical element parameters.
[0051] Specifically, the wavelength of the light source and the target resolution are both known, and the maximum diffraction angle of the target light spot can be obtained by processing based on the wavelength of the light source and the target resolution.
[0052] In one implementation, the preset size of the target light spot satisfies the Nyquist-Shannon sampling theorem, and the formula of the Nyquist-Shannon sampling theorem is: Where D represents the preset size, λ represents the wavelength of the light source, z represents the distance from the sample to the detector, and Δ d Represents the detector pixel size.
[0053] Specifically, the distance from the sample to the detector can be obtained based on historical data. To ensure accurate three-dimensional reconstruction, the distance from the sample to the detector must meet the far-field diffraction condition, that is, the detector needs to be placed in the Fraunhofer diffraction zone. The detector pixel size and the light source wavelength are also known data, so according to the light source wavelength, the distance from the sample to the detector and the detector pixel size, the size that satisfies the Nyquist-Shannon sampling theorem can be obtained. Selecting the size that satisfies the Nyquist-Shannon sampling theorem as the preset size can make the generated spot meet the needs of three-dimensional reconstruction.
[0054] In one implementation, the target resolution is any one of a lateral resolution and a depth resolution; and the processing based on the light source wavelength and the target resolution to obtain a maximum diffraction angle of the target light spot includes:
[0055] If the target resolution is the lateral resolution, then the formula Obtain the maximum diffraction angle of the target light spot, where d x represents the lateral resolution, λ is the wavelength of the light source;
[0056] If the target resolution is depth resolution, then the formula Obtain the maximum diffraction angle of the target light spot, where d z represents the depth resolution, and λ is the wavelength of the light source.
[0057] Specifically, the lateral resolution is the resolution of the imaging system in the x-axis direction, and the depth resolution is the resolution of the imaging system in the z-axis direction. The present invention can support obtaining the maximum diffraction angle of the target spot based on the lateral resolution or the depth resolution, and then inverting using the preset software.
[0058] In one implementation, the preset software is OptiGrating grating design software.
[0059] Specifically, when the target optical element is a grating, the OptiGrating grating design software is used to invert the period length and line width of the grating. The user inputs the amplitude transmittance and maximum diffraction angle of the grating; the software uses the Fourier transform method to simulate and calculate the diffraction angle and efficiency of the grating. If the simulation results do not meet the design requirements, it is necessary to adjust the period or other parameters of the grating, and adjust the grating design through multiple iterations to achieve the expected maximum diffraction angle and other performance indicators. For example, if the grating amplitude transmittance is a two-dimensional periodic function with a period L, the complex function p s (x,y) means that this function can be expanded into a complex-valued Fourier series:
[0060] The coefficient p(x,y) is a complex value, representing the intensity of the plane wave component of the grating transmission function, which is related to the width of the grating line. Its far-field diffraction function (Fourier space) can be expressed as:
[0061] Among them, P s (f x ,f y ) represents p s Fourier transform of (x,y). According to P s (f x ,f y ), the software can calculate the diffraction efficiency and diffraction angle of the grating. After the software calculates the simulation results, it compares them with the target maximum diffraction angle and diffraction efficiency. If the simulation results do not meet the design requirements (for example, the maximum diffraction angle does not meet the requirements), it is necessary to adjust the period length or other design parameters of the grating. The design parameters are adjusted through multiple iterations to optimize the grating design to achieve the expected diffraction angle and efficiency.
[0062] See also Figure 1 The three-dimensional stacked imaging method described in the embodiment of the present invention comprises the following steps:
[0063] Step S200: deploy a light source, a target optical element, a sample and a two-dimensional detector in sequence along the light path.
[0064] Specifically, Figure 2 As shown in the figure, the light source, target optical element, sample and two-dimensional detector are deployed in sequence along the optical path. When the light source emits light, the light can propagate along the optical path. Since the target optical element is used to modulate the illumination angle, the target light spot contains parallel light of multiple incident angles. The sample can be scanned by simply translating the sample. There is no need to rotate the sample to obtain multi-angle diffraction images, which effectively reduces the time of data acquisition.
[0065] See also Figure 1 The three-dimensional stacked imaging method described in the embodiment of the present invention comprises the following steps:
[0066] Step S300: After the light source emits light, it is processed by the target optical element to generate a target light spot and irradiates the sample, and the sample is controlled to translate in a preset manner to obtain multiple diffraction signals of the sample, wherein the target light spot contains parallel light of multiple incident angles.
[0067] Specifically, in the prior art, the 3D stack imaging algorithm is a simple combination of the stack phase recovery algorithm and the 3D reconstruction algorithm, without deep coupling. The iterative phase recovery and CT reconstruction independently constrain the collected data, and each reconstruction step is separate. This method mainly collects diffraction patterns at multiple angles for reconstruction by rotating the sample. The sample scanning schematic diagram is shown in the figure. Figure 3 As shown. Since only two-dimensional reconstruction of the sample is achieved in the reconstruction of a single angle, the depth information in the scanning diffraction data is discarded, and the three-dimensional information in the scanning coherent diffraction data is not fully exploited, so the data acquisition time is too long. At the same time, the stacked-CT imaging method in the prior art is not suitable for thick samples and strongly scattering samples. Specifically, this method requires stacked diffraction imaging technology (ptychography) to reconstruct the scan at a single angle, and the sample function is assumed to be a two-dimensional transmission function. Therefore, this method still needs to meet the thin sample approximation conditions. The three-dimensional effect of multiple scattering may make the relationship between the outgoing wave and the projection of the sample very weak. This effect will be more obvious in strong phase samples or thick samples, resulting in a reduction in the quality of the three-dimensional reconstruction of the sample or even a failure of reconstruction. In addition, the data needs to be calibrated in CT data processing, so the data processing process is complicated and may cause position registration errors. The present invention uses the target optical element to diffract the illumination to perform angle modulation, which is equivalent to scanning the sample with parallel light at different incident angles, thereby collecting sufficient three-dimensional information of the sample. The cross-sectional schematic diagram of the light scanning sample in the three-dimensional stacked imaging method of the present invention is shown in Figure 4 As shown. This method can effectively shorten the data acquisition time, and only a small amount of angle scanning of the sample is required, or even no rotation scanning is required, to obtain the three-dimensional information of the sample, which can effectively reduce the radiation damage of the sample. At the same time, since this method realizes angle modulation by optical means, there is no mechanical scanning error, and no data calibration is required, which effectively avoids the problems of insufficient depth information mining, large reconstruction errors, and long reconstruction time in the existing two-step reconstruction method.
[0068] See also Figure 1 The three-dimensional stacked imaging method described in the embodiment of the present invention comprises the following steps:
[0069] Step S400: using the two-dimensional detector to collect all the diffraction signals to generate a plurality of two-dimensional diffraction patterns, and reconstructing the signals based on all the two-dimensional diffraction patterns using a gradient descent method to obtain a three-dimensional reconstructed image of the sample.
[0070] Specifically, a two-dimensional detector is a detector that can simultaneously record diffraction signals in multiple directions. It has high spatial resolution and sensitivity and can capture rich diffraction information. The diffraction pattern is the interference pattern formed after the light wave passes through the sample. It contains the structural information of the sample and is an important data source for three-dimensional reconstruction. The gradient descent method is an optimization algorithm used to find the local minimum of a function. In three-dimensional reconstruction, the gradient descent method is used to iteratively update the parameters to minimize the difference between the reconstructed image and the original diffraction pattern, thereby obtaining the final three-dimensional reconstruction result.
[0071] In one implementation, reconstructing a signal based on all of the two-dimensional diffraction patterns using a gradient descent method to obtain three-dimensional image data of the sample includes:
[0072] Uniformly stratifying the sample according to the spatial coordinates of the sample to obtain a plurality of slices;
[0073] Acquire an initial probe function, a sample function of each slice layer, and a relative position vector between the sample and the target spot, and perform calculation based on the initial probe function, the sample function of the first slice layer, and the relative position vector to obtain an output wave function of the first slice layer;
[0074] Iteratively use the output wave function of the previous slice as the probe function of the current slice, and calculate the output wave function according to the sample function and probe function of the current slice, until the output wave function of the last slice is obtained;
[0075] The outgoing wave function of the last slice is propagated to a two-dimensional detector to obtain a simulated diffraction pattern;
[0076] Obtaining a preset initial wavefront function, comparing the simulated diffraction pattern with all the two-dimensional diffraction patterns, adjusting the initial wavefront function by a gradient descent method, and obtaining a second wavefront function;
[0077] Back-propagating the second wavefront function back to the sample plane to update the sample function of each slice layer, repeating the back-propagation and updating steps until a preset round, to obtain the final sample function of each slice layer;
[0078] The three-dimensional inversion processing is performed based on the final sample function of each slice layer to obtain a three-dimensional reconstructed image of the sample.
[0079] Specifically, the basic reconstruction process is as follows: (1) The sample is divided into many layers along the longitudinal direction, and the probe function P(r) is irradiated onto the first layer of the sample O 1 (r), the outgoing wave function on the first layer is obtained as: ψ j,1 (r) = P j,1 (rR j )·O j,1 (r), where r represents the real space (sample space) coordinate vector, j represents the jth scanning position, and R j Represents the relative position vector between the sample and the target spot, and the second subscript of O, P and ψ represents the number of slices. (2) The outgoing wave function of the first layer is used as the probe function of the second layer. The outgoing wave propagates freely to the second slice through the near field and multiplies it with the second sample function. After propagating layer by layer, it finally reaches the last slice. The outgoing wave of the last slice is considered to have penetrated the sample. This process can be expressed by the angular spectrum propagation formula:
[0080] Where Δz n =z n+1 -z n represents the nth slice and the n+1th slice, TΔz n Denote the distance Δz n The angular spectrum propagation operator is expressed as: in, is the Fourier transform operator, is the inverse Fourier transform operator, u represents the inverse space coordinate, ψ represents the wavefront function, and λ is the X-ray wavelength. (3) The outgoing wave of the last slice propagates freely to the detector plane in the far field, and the initial wavefront function of the detector plane is obtained: (4) Based on the diffraction pattern After replacing the wavefront function amplitude on the detector plane, the second wavefront function is obtained: (5) Back-propagate the updated second wavefront function to the sample plane to obtain the new output wave function of the last slice: (6) Update the sample function of the last slice using the following formula: Among them, α and β are update relaxation parameters, which can adjust the update speed, and their value range is usually between 0 and 1. (7) The probe function P of the nth slice j+1,n， (r) is regarded as the result of free propagation of the outgoing wave of the n-1th slice. Therefore, the probe function of the nth slice can be back-propagated to the n-1th layer using the inverse process of the propagation formula in step (2), and the slice of the n-1th layer can be updated using the update formula in step (6). Then, all slices are updated in turn through back propagation layer by layer. Repeat the back propagation and update steps until the preset rounds to obtain the final sample function of each slice layer, and then perform three-dimensional inversion processing based on the final sample function of each slice layer to obtain a three-dimensional reconstructed image of the sample.
[0081] The reconstruction method of the present invention adopts a direct 3D reconstruction method, which avoids the problems of insufficient depth information mining, large reconstruction errors, and long reconstruction time in the existing 3D stack imaging method using a two-step reconstruction method. The traditional method uses a two-step method for reconstruction. When performing two-dimensional reconstruction, the following thin sample approximation conditions need to be met, requiring the sample to have weak scattering performance and a certain thickness limit. The approximate conditions are expressed as: Where T is the sample thickness, R is the effective resolution of the detector, and a is the effective resolution of the illumination. The present invention uses a multi-slice method for reconstruction, which has no restriction on the sample thickness, and only requires that the spacing between adjacent slices in the reconstruction algorithm is less than the thickness requirement in the thin sample approximation.
[0082] In one implementation, the light source is visible light or X-rays.
[0083] In one implementation, the target optical element is any one of a spatial light modulator, a refractive lens, a zone plate, a compound refractive index lens, a grating, and a crystal.
[0084] Specifically, the target optical element of the present invention is a diffractive optical element or a refractive optical element. By modulating the angle of the coherent illumination light through the target optical element, a target light spot (i.e., a local probe) with a high numerical aperture or a high diffraction angle can be obtained. The target light spot is used to perform a two-dimensional plane scan of the three-dimensional sample, and the illumination areas of adjacent scanning positions have a high degree of overlap, and the diffraction signal of the sample is collected in the Fraunhofer diffraction area to achieve efficient encoding of the three-dimensional information of the sample. According to the collected far-field diffraction signal, the three-dimensional reconstruction of the three-dimensional sample and the illumination light spot can be quickly achieved by the gradient descent method. If the light source is visible light, a spatial light modulator or a refractive lens with a high numerical aperture can be used for wavefront modulation. If the light source is X-rays, any one of a composite refractive index lens, a grating, and a crystal can be used for wavefront modulation. The modulated light can be multiple beams of rays separated from each other, or it can be a single beam of rays whose light intensity changes continuously with the angle. There is no essential difference between the two from the perspective of encoding the three-dimensional information of the sample.
[0085] In summary, the present invention obtains optical element parameters and configures the target optical element using the optical element parameters; deploys the light source, target optical element, sample and two-dimensional detector in sequence along the light path; when the light source emits light, a target light spot is generated and irradiated onto the sample, and the sample is controlled to translate in a preset manner to obtain multiple diffraction signals of the sample, wherein the target light spot contains parallel light of multiple incident angles; and generates a three-dimensional reconstructed image of the sample. The present invention generates a target light spot of parallel light containing multiple incident angles by using a target optical element, and controls the sample to translate in a preset manner, so that samples in different areas are sequentially irradiated by the target light spot, thereby generating multiple diffraction signals containing information of different parts of the sample, which can avoid rotating the sample to collect diffraction patterns at multiple angles, and effectively reduces the data acquisition time.
[0086] In one embodiment, if Figure 5 As shown, based on the above three-dimensional stacked imaging method, the present invention also provides a three-dimensional stacked imaging device, including:
[0087] The component setting module 100 is used to obtain preset optical component parameters and configure the target optical component using the optical component parameters;
[0088] The device deployment module 200 is used to sequentially deploy the light source, the target optical element, the sample and the two-dimensional detector along the optical path;
[0089] The signal generating module 300 is used to generate a target light spot after the light source emits light, and then irradiate the target light spot onto the sample after being processed by the target optical element, and control the sample to translate in a preset manner to obtain multiple diffraction signals of the sample;
[0090] The three-dimensional reconstruction module 400 is used to collect all the diffraction signals using the two-dimensional detector to generate multiple two-dimensional diffraction patterns, and reconstruct the signals based on all the two-dimensional diffraction patterns using the gradient descent method to obtain a three-dimensional reconstructed image of the sample.
[0091] It should be noted that the above explanation of the three-dimensional stacked imaging method embodiment is also applicable to the three-dimensional stacked imaging device of this embodiment, and will not be repeated here.
[0092] Based on the above embodiment, the present invention further provides a terminal, whose principle block diagram can be shown as follows: Figure 6 As shown. The terminal includes a processor, a memory, a network interface and a display screen connected via a device bus. The processor of the terminal is used to provide computing and control capabilities. The memory of the terminal includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating device and a three-dimensional stacked imaging program. The internal memory provides an environment for the operation of the operating device and the three-dimensional stacked imaging program in the non-volatile storage medium. The network interface of the terminal is used to communicate with an external terminal via a network connection. When the three-dimensional stacked imaging program is executed by the processor, the steps of any one of the three-dimensional stacked imaging methods described above are implemented. The display screen of the terminal can be a liquid crystal display screen or an electronic ink display screen.
[0093] Those skilled in the art will understand that Figure 6 The principle block diagram shown in the figure is only a block diagram of a partial structure related to the scheme of the present invention, and does not constitute a limitation on the terminal to which the scheme of the present invention is applied. The specific terminal may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.
[0094] In one embodiment, a terminal is provided, comprising a memory, a processor, and a three-dimensional stacked imaging program stored in the memory and executable on the processor, wherein the three-dimensional stacked imaging program, when executed by the processor, implements the steps of any one of the three-dimensional stacked imaging methods provided in an embodiment of the present invention.
[0095] An embodiment of the present invention further provides a computer-readable storage medium, on which a three-dimensional stacked imaging program is stored. When the three-dimensional stacked imaging program is executed by a processor, the steps of any one of the three-dimensional stacked imaging methods provided in the embodiments of the present invention are implemented.
[0096] It should be understood that the serial numbers of the steps in the above embodiments do not imply a sequence of execution, and the execution sequence of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present invention.
[0097] Those skilled in the art can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional units and modules is used as an example for illustration. In practical applications, the above-mentioned function allocation can be completed by different functional units and modules as needed, that is, the internal structure of the above-mentioned device can be divided into different functional units or modules to complete all or part of the functions described above. The functional units and modules in the embodiment can be integrated in a processing unit, or each unit can exist physically separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional units. In addition, the specific names of the functional units and modules are only for the convenience of distinguishing each other, and are not used to limit the scope of protection of the present invention. The specific working process of the units and modules in the above-mentioned device can refer to the corresponding process in the aforementioned method embodiment, which will not be repeated here.
[0098] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.
[0099] Those skilled in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.
[0100] In the embodiments provided by the present invention, it should be understood that the disclosed apparatus / terminal equipment and method can be implemented in other ways. For example, the apparatus / terminal equipment embodiments described above are only illustrative, for example, the division of the above modules or units is only a logical function division, and in actual implementation, other division methods can be used, for example, multiple units or components can be combined or integrated into another apparatus, or some features can be ignored or not executed.
[0101] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it should be understood by those skilled in the art that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features therein may be replaced by equivalents. However, these modifications or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should be included in the protection scope of the present invention.
Claims
1. A three-dimensional stacked imaging method, characterized in that: The method comprises: Acquire preset optical element parameters, and configure the target optical element using the optical element parameters; A light source, a target optical element, a sample, and a two-dimensional detector are sequentially deployed along the optical path; When the light source emits light, the light is processed by the target optical element to generate a target light spot and irradiates the sample, and the sample is controlled to translate in a preset manner to obtain multiple diffraction signals of the sample, wherein the target light spot contains parallel light of multiple incident angles; The two-dimensional detector is used to collect all the diffraction signals to generate a plurality of two-dimensional diffraction patterns, and the signal is reconstructed based on all the two-dimensional diffraction patterns using a gradient descent method to obtain a three-dimensional reconstructed image of the sample.
2. The three-dimensional stacked imaging method according to claim 1, characterized in that: The method for generating the optical element parameters comprises: Acquire the preset light source wavelength and target resolution of the imaging system, and perform processing based on the light source wavelength and the target resolution to obtain the maximum diffraction angle of the target light spot; The preset size of the target light spot is obtained, and preset software is used to perform inversion based on the maximum diffraction angle and the preset size to obtain optical element parameters.
3. The three-dimensional stacked imaging method according to claim 2, characterized in that: The preset size of the target light spot satisfies the Nyquist-Shannon sampling theorem, and the formula of the Nyquist-Shannon sampling theorem is: Where D represents the preset size, λ represents the wavelength of the light source, z represents the distance from the sample to the detector, and Δ d Represents the detector pixel size.
4. The three-dimensional stacked imaging method according to claim 2, characterized in that: The target resolution is any one of a lateral resolution and a depth resolution; the processing based on the light source wavelength and the target resolution to obtain the maximum diffraction angle of the target light spot includes: If the target resolution is the lateral resolution, then the formula Obtain the maximum diffraction angle of the target light spot, where d x represents the lateral resolution, λ is the wavelength of the light source; If the target resolution is depth resolution, then the formula Obtain the maximum diffraction angle of the target light spot, where d z represents the depth resolution, and λ is the wavelength of the light source.
5. The three-dimensional stacked imaging method according to claim 1, characterized in that: The step of reconstructing signals based on all the two-dimensional diffraction patterns using a gradient descent method to obtain three-dimensional image data of the sample includes: Uniformly stratifying the sample according to the spatial coordinates of the sample to obtain a plurality of slices; Acquire an initial probe function, a sample function of each slice layer, and a relative position vector between the sample and the target spot, and perform calculation based on the initial probe function, the sample function of the first slice layer, and the relative position vector to obtain an output wave function of the first slice layer; Iteratively use the output wave function of the previous slice as the probe function of the current slice, and calculate the output wave function according to the sample function and probe function of the current slice, until the output wave function of the last slice is obtained; The outgoing wave function of the last slice is propagated to a two-dimensional detector to obtain a simulated diffraction pattern; Obtaining a preset initial wavefront function, comparing the simulated diffraction pattern with all the two-dimensional diffraction patterns, adjusting the initial wavefront function by a gradient descent method, and obtaining a second wavefront function; Back-propagating the second wavefront function back to the sample plane to update the sample function of each slice layer, repeating the back-propagation and updating steps until a preset round, to obtain the final sample function of each slice layer; The three-dimensional inversion processing is performed based on the final sample function of each slice layer to obtain a three-dimensional reconstructed image of the sample.
6. The three-dimensional stacked imaging method according to claim 1, characterized in that: The light source is visible light or X-rays.
7. The three-dimensional stacked imaging method according to claim 1, characterized in that: The target optical element is any one of a spatial light modulator, a refractive lens, a zone plate, a compound refractive index lens, a grating, and a crystal.
8. A three-dimensional stacked imaging device, characterized in that: include: An element setting module is used to obtain preset optical element parameters and configure a target optical element using the optical element parameters; A device deployment module, used to sequentially deploy a light source, a target optical element, a sample, and a two-dimensional detector along an optical path; A signal generating module, which is used to generate a target light spot after the light source emits light, and irradiate the target light spot onto the sample after being processed by the target optical element, and control the sample to translate in a preset manner to obtain multiple diffraction signals of the sample; The three-dimensional reconstruction module is used to collect all the diffraction signals using the two-dimensional detector to generate multiple two-dimensional diffraction patterns, and reconstruct the signals based on all the two-dimensional diffraction patterns using the gradient descent method to obtain a three-dimensional reconstructed image of the sample.
9. A terminal, characterized in that: The terminal includes a memory, a processor, and a three-dimensional stacked imaging program stored in the memory and executable on the processor. When the three-dimensional stacked imaging program is executed by the processor, the steps of the three-dimensional stacked imaging method according to any one of claims 1 to 7 are implemented.
10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a three-dimensional stacked imaging program, and when the three-dimensional stacked imaging program is executed by a processor, the steps of the three-dimensional stacked imaging method according to any one of claims 1 to 7 are implemented.