Bimodal imaging system, imaging method, device and storage medium

Abstract

The invention relates to the technical field of microscopic imaging, and provides a bimodal imaging system, an imaging method, a device and a storage medium, and the method comprises the steps: generating two laser beams as illumination light and reference light respectively; in the light intensity diffraction tomography mode, lighting light is turned on, the electric diaphragm is turned off to block the reference light, the lighting light passes through an imaging objective lens switched into a low-power objective lens in a first path, and a light intensity diffraction tomography image of the sample is obtained; lighting light is turned on in the optical diffraction tomography mode, an electric diaphragm is turned on to enable the reference light to be propagated along a second path, the lighting light passes through an imaging objective lens switched into a high-power objective lens in a first path, and an optical diffraction tomography image of the sample is obtained; bimodal microscopic imaging is realized based on the light intensity diffraction tomography image and the optical diffraction tomography image; the bimodal imaging system disclosed by the invention is integrated in a set of light path system, and unmarked refractive index imaging of global appearance and local characteristics of a sample can be realized by switching different modes under the control of the subsystem, so that bimodal microscopic imaging is realized.

Description

Technical Field

[0001] This invention relates to the field of microscopic imaging technology, and more particularly to dual-modal imaging systems, imaging methods, devices, and storage media. Background Technology

[0002] Optical diffraction tomography (ODT) is a novel label-free optical imaging technique. This method acquires information about the scattered light field using holographic technology, and then quantitatively obtains the three-dimensional refractive index distribution of the sample using scattering theory. This method is characterized by being label-free, super-resolution, having low phototoxicity, and being free from light drift. It allows for long-term observation of living cells and can observe subcellular organelle structures. Optical diffraction tomography provides a powerful tool for modern biomedical research, especially demonstrating significant advantages in studies requiring the preservation of biological samples in their original state.

[0003] However, optical diffraction tomography, due to its off-axis holographic approach, has low spatial bandwidth utilization. When switching to low-magnification lenses for large-field global imaging, problems such as spectral overlap and a sharp decrease in resolution occur. This issue limits the application scope of optical diffraction tomography.

[0004] Intensity diffraction tomography is also a label-free imaging method. This method does not require holography; it only needs to meet illumination matching conditions, thus acquiring images with a high spatial bandwidth product, making it suitable for label-free imaging with low magnification and a large field of view. However, this method cannot be applied to high numerical aperture, high-magnification objectives, resulting in poor image quality for sample details. Summary of the Invention

[0005] This invention provides a dual-modal imaging system, imaging method, apparatus, and storage medium. Combining intensity diffraction tomography and optical diffraction tomography in dual-modal microscopy, within a single optical path system, by controlling the switching of a low-magnification objective lens and turning off the reference light, intensity diffraction tomography is used for large-field, low-resolution global observation. Then, by switching to a high-magnification objective lens and turning on the reference light, optical diffraction tomography is used for high-resolution three-dimensional refractive index reconstruction of detailed areas. By controlling the switching of the control system, label-free imaging of both the global and detailed aspects of the sample is achieved.

[0006] This invention provides a dual-modal imaging method, comprising: generating two laser beams using a light source system as illumination light and reference light respectively; in the intensity diffraction tomography mode, turning on the illumination light and closing the motorized aperture to block the reference light, the illumination light passing through an imaging objective switched to low magnification via a first path to acquire an intensity diffraction tomography image of the sample; in the optical diffraction tomography mode, turning on the illumination light and opening the motorized aperture to allow the reference light to propagate along a second path, the illumination light passing through an imaging objective switched to high magnification via the first path to acquire an optical diffraction tomography image of the sample; and realizing dual-modal microscopic imaging based on the intensity diffraction tomography image and the optical diffraction tomography image; wherein, the intensity diffraction tomography image is obtained by receiving the scattered light information of the illumination light through the sample via the low magnification objective; the optical diffraction tomography image is obtained by receiving the scattered light information of the reference light and the illumination light through the sample via the high magnification objective.

[0007] According to the present invention, a dual-modal imaging method is provided for acquiring an intensity diffraction tomography image of a sample, comprising: applying illumination light to the sample, receiving the scattered light information of the illumination light through a low-power objective lens in an imaging lens, imaging it onto an industrial camera, and acquiring a first imaging dataset; processing the first imaging dataset using the Kramers-Kronig relation, the Rytov approximation, and a complex deconvolution diffraction tomography 3D reconstruction algorithm to generate an intensity diffraction tomography image.

[0008] According to a dual-modal imaging method provided by the present invention, a first imaging dataset is processed using the Kramers-Kronig relation, the Rytov approximation, and a complex deconvolution diffraction tomography three-dimensional reconstruction algorithm to generate an intensity diffraction tomography image. The method includes: obtaining the complex amplitude at the sample using the Kramers-Kronig relation; obtaining the scattered light field information of the sample using the Rytov approximation; stitching the obtained scattered light field information in the three-dimensional frequency domain; and performing a three-dimensional inverse Fourier transform on the total frequency domain image to obtain the intensity diffraction tomography image.

[0009] According to a dual-modal imaging method provided by the present invention, the complex amplitude at the sample is obtained by utilizing the Kramers-Kronig relation, including: changing the angle of the incident light by adjusting the galvanometer voltage to meet the illumination matching condition, and obtaining the intensity map under different incident angle conditions; using the Kramers-Kronig relation to obtain the phase map of the sample from the intensity map, thereby obtaining the complex amplitude at the sample.

[0010] According to the dual-modal imaging method provided by the present invention, the illumination matching condition is: ;in, Let be the component of the incident wave vector in the x-direction. Let be the component of the incident wave vector in the y-direction. The numerical aperture of the objective lens. Let be the wave vector of the incident light in the air.

[0011] According to the present invention, a dual-modal imaging method is provided for acquiring optical diffraction tomography images of a sample, comprising: acquiring a second dataset of the sample based on illumination light, reference light, and a high-magnification objective lens; extracting a hologram based on the obtained second dataset, recovering the complex amplitude information of the sample from the hologram; and processing the complex amplitude information of the hologram by three-dimensional spectral stitching and inverse Fourier transform using the relationship between the Rytov approximation field and the scattering potential to generate an optical diffraction tomography image.

[0012] According to the present invention, a dual-modal imaging method is provided to achieve dual-modal microscopic imaging based on optical intensity diffraction tomography (OIT) images and optical diffraction tomography (ODT) images. The method includes: performing OIT DDT imaging on a sample in OIT DDT mode to obtain an OIT DDT image; selecting a target region in the OIT DDT image and then switching to ODT mode; performing ODT imaging on the target region in ODT mode to obtain an ODT image of the corresponding target region.

[0013] This invention also provides a dual-modal imaging system using the dual-modal imaging method described above. The dual-modal imaging system includes a light source system, a scanning system, and a detection system. The light source system emits collimated polarized light, which is then split into a first laser and a second laser by a first unpolarized beam splitter. The first laser enters the scanning system as illumination light, and the second laser enters the detection system as reference light. The scanning system includes a dual-axis scanning galvanometer and an electrically driven stage. The dual-axis scanning galvanometer deflects the illumination light to achieve scanning of the sample at different angles. The electrically driven stage is used to place the sample and achieve displacement of the sample in the xy plane. The detection system includes an imaging objective, a second unpolarized beam splitter, an industrial camera, a first reflecting mirror, and an electrically driven aperture. The imaging objective receives scattered light information from the sample. The second unpolarized beam splitter combines the reference light and the object light. The industrial camera receives the light signal used for imaging. The electrically driven aperture controls the opening and closing of the reference light.

[0014] The present invention also provides an electronic device, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the dual-modal imaging method as described above.

[0015] The present invention also provides a non-transitory computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the dual-modal imaging method as described above.

[0016] The present invention provides a dual-modal imaging system, imaging method, device, and storage medium. The dual-modal imaging method includes: generating two laser beams using a light source system as illumination light and a reference light, respectively; in the intensity diffraction tomography mode, turning on the illumination light and closing the motorized aperture to block the reference light, the illumination light passes through an imaging objective switched to low magnification via a first path to acquire an intensity diffraction tomography image of the sample; in the optical diffraction tomography mode, turning on the illumination light and opening the motorized aperture to allow the reference light to propagate along a second path, the illumination light passes through an imaging objective switched to high magnification via the first path to acquire an optical diffraction tomography image of the sample; and realizing dual-modal microscopy imaging based on the intensity diffraction tomography image and the optical diffraction tomography image; wherein the intensity diffraction tomography image is obtained by receiving the scattered light information of the illumination light through the sample via the low magnification objective; and the optical diffraction tomography image is obtained by receiving the scattered light information of the reference light and the illumination light through the sample via the high magnification objective. By employing the above method, this invention combines two label-free microscopic imaging techniques: optical diffraction tomography and intensity diffraction tomography. By controlling the incident wave, intensity diffraction tomography acquires a large-field-of-view, low-resolution, high-throughput cellular refractive index image using large-throughput tomography. Then, optical diffraction tomography acquires a high-resolution, small-field-of-view cellular refractive index image of a local area. This dual-modal imaging system is integrated into a single optical path system. By controlling the switching of different modes through subsystems, label-free refractive index imaging of both the global appearance and local features of the sample can be achieved. This invention achieves dual-modal microscopic imaging by using intensity diffraction tomography to image a large area of ​​the sample and simultaneously using optical diffraction tomography to recover the local refractive index of the sample. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart of the dual-modal imaging method provided in an embodiment of the present invention.

[0019] Figure 2 This is a schematic diagram of the structure of a dual-modal imaging system combining optical diffraction tomography and optical intensity diffraction tomography provided in an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram of the spectrum of light intensity diffraction tomography provided in an embodiment of the present invention when the illumination matching condition is met.

[0021] Figure 4 This is a flowchart of the galvanometer optimization algorithm based on frequency domain analysis provided in an embodiment of the present invention to meet the lighting matching conditions.

[0022] Figure 5 This is a schematic diagram of the spectrum of an image obtained by off-axis holography in optical diffraction tomography provided in an embodiment of the present invention.

[0023] Figure 6 This is a schematic flowchart of a dual-modal imaging system combining optical diffraction tomography and intensity diffraction tomography provided in an embodiment of the present invention.

[0024] Figure 7 This is a schematic diagram of the physical structure of the electronic device provided in an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0026] Please see Figure 1-2 , Figure 1 This is a schematic flowchart of the dual-modal imaging method provided in an embodiment of the present invention. Figure 2 This is a schematic diagram of the structure of a dual-modal imaging system combining optical diffraction tomography and optical intensity diffraction tomography provided in an embodiment of the present invention.

[0027] In this embodiment, the dual-modal imaging system may include a light source system, a scanning system, and a detection system. The dual-modal imaging system may use a dual-modal imaging method. The dual-modal imaging method may include steps S110 to S140, each step of which is as follows: S110: Two laser beams are generated using a light source system, serving as illumination light and reference light respectively.

[0028] S120: In the light intensity diffraction tomography mode, the illumination light is turned on, the motorized aperture is turned off to block the reference light, and the illumination light passes through the imaging objective lens, which is switched to a low-power objective lens, in the first path to acquire the light intensity diffraction tomography image of the sample.

[0029] S130: In optical diffraction tomography mode, the illumination light is turned on, the motorized aperture is opened to allow the reference light to propagate along the second path, and the illumination light passes through the imaging objective lens, which is switched to a high-power objective lens, along the first path to acquire the optical diffraction tomography image of the sample.

[0030] S140: Dual-modal microscopy based on intensity diffraction tomography and optical diffraction tomography.

[0031] Among them, the light intensity diffraction tomography image is obtained by receiving the scattered light information of the illumination light through the sample using a low-magnification objective lens; the optical diffraction tomography image is obtained by receiving the scattered light information of the reference light and the illumination light through the sample using a high-magnification objective lens.

[0032] The dual-modal imaging system of this embodiment is a microscopic imaging system, including an intensity diffraction tomography (IDT) mode and an optical diffraction tomography (ODT) mode. Both are label-free imaging systems capable of long-term, label-free, non-invasive panoramic imaging of live cells.

[0033] Intensity diffraction tomography (IDT) can achieve millimeter-level field of view, while optical diffraction tomography (ODT) can surpass the diffraction limit to achieve super-resolution imaging. This embodiment uses a dual-mode system, which can effectively compensate for the poor resolution of IDT and the small field of view of ODT. Specifically, the IDT mode is used to acquire a large-field-of-view, low-resolution global image, while the ODT mode acquires a small-field-of-view, high-resolution local image. Combining the two allows for convenient observation of the entire sample while also enabling high-resolution imaging of local areas.

[0034] In a dual-modal imaging system, the light source system is used to emit collimated polarized light, which is then split into a first laser and a second laser by a first unpolarized beam splitter. The first laser enters the scanning system along a first path as illumination light, and the second laser enters the detection system along a second path as reference light.

[0035] The scanning system includes a biaxial scanning galvanometer and an electrically driven stage. The biaxial scanning galvanometer is used to deflect the illumination light to achieve scanning of the sample at different angles; the electrically driven stage is used to place the sample to achieve displacement of the sample in the xy plane.

[0036] The detection system includes an imaging objective, a second unpolarized beam splitter, an industrial camera, a first reflecting mirror, and a motorized aperture. The imaging objective is used to receive the scattered light information from the sample; the second unpolarized beam splitter combines the reference light and the object light (i.e., the illumination light after passing through the sample); the industrial camera is used to receive the optical signal used for imaging; and the motorized aperture is used to control the opening and closing of the reference light, i.e., to determine whether the reference light can continue to propagate along the second path.

[0037] Specifically, the dual-axis scanning galvanometer is one of the core components for realizing dual-mode functionality. This device not only provides multi-angle incident illumination required for optical diffraction tomography, enabling synthetic aperture imaging and thus breaking through the diffraction limit of traditional optical systems and improving imaging resolution; but also, by dynamically adjusting its scanning angle and combining it with feedback control algorithms, it can meet the stringent requirements for illumination direction and matching conditions in intensity diffraction tomography, thereby ensuring the accuracy of reconstruction in IDT mode.

[0038] An electrically driven stage is used to achieve efficient switching between two imaging modes. Considering that IDT (Intensity Dispersive Thomography) has a larger field of view, while optical diffraction tomography (ODT) has a smaller field of view and requires more precise sample positioning, if the target cell is located at the edge of the IDT imaging field of view, directly switching to the ODT mode may not result in the complete capture of the sample image within the camera's field of view. Therefore, this embodiment also incorporates an image feedback mechanism to control the precise movement of the electrically driven stage, automatically moving the target sample to the center of the field of view before switching to the ODT mode. This not only effectively reduces optical aberrations but also ensures accurate acquisition of high-resolution images.

[0039] Furthermore, the motorized aperture, as a key component for mode switching, has optical path switching control functionality. In intensity diffraction tomography, no reference light is required; however, in optical diffraction tomography, a reference light is needed to form an interference pattern. The motorized aperture can rapidly switch the reference light path, ensuring seamless transition and automated conversion between the two imaging modes.

[0040] In summary, the dual-modal imaging system provided in this embodiment is highly integrated in terms of structural design and functional implementation, and has the advantages of flexible switching, complementary functions, and high spatial alignment accuracy, which can better meet the imaging needs of complex biological samples.

[0041] In some embodiments, the dual-modal imaging system may further include a control system, which includes a computer and a data acquisition system (DAQ). The computer controls the data acquisition system, and the digital acquisition card of the data acquisition system sends analog signals to the dual-axis scanning galvanometer, the motorized displacement stage, the motorized aperture, and the industrial camera to achieve synchronous control.

[0042] Specifically, the light source system generates two laser beams, designated as a first laser and a second laser. The first laser enters the scanning system for scanning at different angles, while the second laser enters the detection system as a reference beam to form a hologram. The scanning system employs multi-angle laser scanning for optical diffraction tomography and illumination matching and multi-angle laser scanning for intensity diffraction tomography. The detection system is used for intensity map measurement in intensity diffraction tomography and hologram measurement in optical diffraction tomography. The control system controls the laser scanning angle and the sample position.

[0043] Therefore, by turning off the second laser and using the first laser to scan the sample in the detection system to obtain an intensity map, a light intensity diffraction tomography pattern is obtained. Then, by turning on the second laser and using the first laser to scan the sample in the detection system to obtain a hologram, an optical diffraction tomography pattern is obtained. Based on the light intensity diffraction tomography pattern and the optical diffraction tomography pattern, a global low-resolution and a local high-resolution dual-modal fusion image is obtained.

[0044] In this embodiment, two laser beams are used as the illumination beam and the reference beam. When the intensity diffraction tomography mode is activated, only the illumination beam is used. At this time, the reference beam is blocked by closing the motorized aperture, allowing the illumination beam to propagate along the first path. The imaging objective is switched to a low-magnification objective. The use of the low-magnification objective allows for observation of the sample within a relatively large field of view, thereby acquiring an intensity diffraction tomography image of the sample. The intensity diffraction tomography image can reflect the macroscopic intensity distribution and approximate structural information of the sample.

[0045] In optical diffraction tomography mode, the optical path configuration is changed: the illumination light is turned on while the motorized aperture is opened, allowing the reference light to propagate along the second path. Meanwhile, the illumination light continues along the first path. The imaging objective is switched to a high-power objective. The high-power objective allows for more detailed observation of localized areas of the sample, acquiring optical diffraction tomography images. These images reveal detailed information about the sample's microscopic structure, material distribution, and refractive index variations.

[0046] By combining the different levels and types of information contained in both intensity diffraction tomography (IDT) and optical diffraction tomography (ODT), dual-modal microscopy imaging can be achieved. Furthermore, the dual-modal imaging system of this invention is highly integrated, integrating all the optical components and control parts required to achieve dual-modal imaging into a single optical path system. The subsystems precisely control the operating states of each component in different modes, such as controlling the opening and closing of the motorized aperture and switching imaging objectives. This facilitates label-free refractive index imaging of both the global appearance of the sample (using low-magnification objective imaging in IDT mode) and local features (using high-magnification objective imaging in ODT mode), ultimately achieving the effect of dual-modal microscopy imaging.

[0047] The method provided in this embodiment can obtain both light intensity diffraction tomography (LED) images and optical diffraction tomography (ODT) images. The former can display the macroscopic light intensity distribution and overall structure of the sample, while the latter can reveal the microscopic fine structure and details of refractive index changes. The combined dual-modal microscopic imaging results help to analyze the characteristics of samples more accurately, which is especially important for the study of some complex samples at different scales. In addition, the dual-modal imaging system is integrated into a single optical path system. This highly integrated design not only greatly reduces the space occupied by the equipment but also improves the stability and reliability of the system. In actual operation, there is no need to frequently replace or adjust a large number of independent optical components. Different modes can be easily switched through subsystem control, making the equipment more convenient and efficient to use. This facilitates rapid and flexible imaging work in different research scenarios, thereby improving scientific research efficiency.

[0048] Continue reading Figure 2 The light source system may include a laser 1, a first lens 2, and a first unpolarizing beam splitter 3. The scanning system may include a dual-axis scanning galvanometer 4, a second lens 5, a third lens 6, and an electrically driven stage 7. The detection system may include an imaging objective lens 8, a fourth lens 9, a fifth lens 10, a second unpolarizing beam splitter 11, a sixth lens 12, an industrial camera 13, a first reflector 14, an electrically driven aperture 15, a second reflector 16, and a seventh lens 17.

[0049] The biaxial scanning galvanometer 4 is used to deflect the illumination light, enabling scanning of the sample at different angles. The second lens 5 and the third lens 6 form a 4-f system, the purpose of which is to conjugate the surfaces of the biaxial scanning galvanometer 4 onto the object surface. The electrically driven displacement stage 7 is used to place the sample, achieving precise displacement of the sample in the xy plane.

[0050] Imaging objective 8 is used to receive scattered light information from the sample. The fourth lens 9 acts as a tube lens, forming a 4-f imaging system with imaging objective 8. The fifth lens 10 and the sixth lens 12 form a 4-f system, which, together with the aforementioned imaging objective 8 and the fourth lens 9, constitutes an 8-f system, conjugating the sample surface onto the sensor surface of the industrial camera 13 to achieve imaging.

[0051] The second unpolarizing beam splitter 11 combines the reference beam and the object beam to form an off-axis hologram on the industrial camera 13. The motorized aperture 15 is used to control the opening and closing of the reference beam.

[0052] In the embodiments of this application, the laser emitted by the laser 1 is collimated by the first lens 2, and the collimated laser beam is split into a first laser and a second laser by the first unpolarized beam splitter 3.

[0053] On one hand, the first laser (i.e., illumination light) illuminates the sample placed on the electric displacement stage 7 after passing through the dual-axis scanning galvanometer 4, the second lens 5, and the third lens 6 along the first path. The light passing through the sample is collected by the imaging objective lens 8 and then sequentially passes through the fourth lens 9, the fifth lens 10, the second non-polarizing beam splitter 11, and the sixth lens 12 before being imaged onto the industrial camera 13.

[0054] On the other hand, the second laser, following the second path, passes through the first reflecting mirror 14, the motorized aperture 15, the second reflecting mirror 16, the seventh lens 17, the second unpolarized beam splitter 11, and the sixth lens 12, and becomes a reference light that forms an interference hologram with the first laser on the industrial camera 13.

[0055] Furthermore, when using the intensity diffraction tomography mode, the motorized aperture 15 is closed to prevent the second laser from reaching the industrial camera 13, and the imaging objective is switched to a low-magnification objective. The dual-axis scanning galvanometer 4 is controlled to change the laser illumination angle to achieve illumination matching conditions, and the sample intensity map is obtained by scanning the sample in a ring, thereby obtaining the intensity diffraction tomography image.

[0056] When using optical diffraction tomography, the motorized aperture 15 is opened to allow the second laser to reach the industrial camera 13 and form an interference hologram. The imaging objective is then switched to a high-magnification objective. The dual-axis scanning galvanometer 4 is controlled to change the laser illumination angle, and the sample is scanned to acquire a hologram, thereby obtaining an optical diffraction tomography image.

[0057] In the example of this application, the entire imaging system can be modified based on a commercial lens frame. The imaging objective lens 8 is placed on the objective lens tray, so that when switching between different shooting modes, the objective lens of different magnifications can be switched directly without the need for refocusing.

[0058] The detection system connects to the rear opening of the commercial frame to detect the light collected by the imaging objective 8.

[0059] The scanning module can be directly fixed to the dovetail mount above the commercial eyeglass frame by a cage system.

[0060] Laser 1 can be a laser with a wavelength of 532nm.

[0061] The first lens 2 can be a cemented doublet lens with a focal length of 50mm.

[0062] The first unpolarized beam splitter 3 can be a polarization-independent cubic beam splitter with a splitting ratio of 50:50.

[0063] The dual-axis scanning galvanometer 4 can be an 8107 galvanometer.

[0064] The second lens 5 can be a cemented doublet with a focal length of 80mm; the third lens 6 can be a condenser lens with an NA of 0.7.

[0065] The motorized stage 7 can be a motorized stage that is compatible with commercial microscope stands.

[0066] Imaging objective 8 may include two switchable objectives with different magnifications, both working in air and having the same parfocal distance. For example, imaging objective 8 may use a 10x air objective for intensity diffraction tomography and a 60x air objective for optical diffraction tomography.

[0067] The fourth lens 9 can be a cemented doublet with a focal length of 180mm; the fifth lens 10 can be a cemented doublet with a focal length of 100mm.

[0068] The second unpolarized beam splitter 11 can be a polarization-independent cubic beam splitter with a splitting ratio of 50:50.

[0069] The sixth lens 12 can be a cemented doublet with a focal length of 100mm; the seventh lens 17 can be a cemented doublet with a focal length of 50mm.

[0070] The first reflector 14 can be a 2-inch silver-plated reflector; the second reflector 16 can be a 2-inch silver-plated reflector.

[0071] The motorized aperture 15 can quickly open and close the reference light. Furthermore, the control system can switch between objectives of different magnifications, thereby enabling switching between intensity diffraction tomography and optical diffraction tomography. Optionally, the motorized aperture 15 can be a laser shutter, such as the Uniblitz LS6.

[0072] In some embodiments, the step of acquiring an intensity diffraction tomography image of a sample may specifically include: Illumination light is applied to the sample, and the scattered light information from the sample is received by a low-magnification objective lens in the imaging lens and imaged onto an industrial camera to obtain the first imaging dataset. The first imaging dataset is then processed using the Kramers-Kronig relation, the Rytov approximation, and the complex deconvolution diffraction tomography 3D reconstruction algorithm to generate an intensity diffraction tomography image.

[0073] In this embodiment, illumination light is applied to the sample. When the illumination light shines on the sample, it interacts with the substances within the sample, generating scattered light. This scattered light contains important information about the sample's internal structure and optical properties. This scattered light is received by a low-magnification objective lens in the imaging lens and imaged onto an industrial camera, thereby acquiring the first imaging dataset. The low-magnification objective lens provides a large field of view, which is beneficial for obtaining information about the overall light intensity distribution of the sample, providing basic data for subsequent image processing and 3D reconstruction.

[0074] In addition, this embodiment also utilizes data processing algorithms such as the Kramers-Kronig relation, the Rytov approximation, and the complex deconvolution diffraction tomography 3D reconstruction algorithm to perform in-depth mining and precise processing of the original scattered light data, effectively improving the accuracy and resolution of imaging.

[0075] By utilizing the Kramers-Kronig relation, the acquired light intensity data can be processed to indirectly obtain information such as the complex refractive index of the sample. The Rytov approximation approximates the phase and amplitude changes of light waves, and applying the Rytov approximation makes it easier to estimate and process the phase information of scattered light waves.

[0076] The deconvolutional diffraction tomography 3D reconstruction algorithm is a specialized algorithm for diffraction tomography imaging. By performing deconvolutional processing on the acquired multi-angle, multi-view scattered light intensity data, it can effectively remove interference factors such as blur and artifacts in the image, improving image resolution and contrast. Simultaneously, utilizing the principles of diffraction tomography, it reconstructs the internal structure of the sample in three dimensions based on the diffraction characteristics of light, thereby generating a high-precision and high-resolution light intensity diffraction tomography image, clearly revealing the sample's internal three-dimensional structure.

[0077] In some embodiments, the step of processing the first imaging dataset using the Kramers-Kronig relation, Rytov approximation, and complex deconvolution diffraction tomography 3D reconstruction algorithm to generate an intensity diffraction tomography image may specifically include: The complex amplitude at the sample is obtained using the Kramers-Kronig relation; the scattered light field information of the sample is obtained using the Rytov approximation; the obtained scattered light field information is stitched together in the three-dimensional frequency domain, and the overall frequency domain image is subjected to a three-dimensional inverse Fourier transform to obtain the light intensity diffraction tomography image.

[0078] This embodiment details the application of three data processing methods. By combining the Kramers-Kronig relation and the Rytov approximation, not only light intensity information can be obtained, but also phase information and detailed information about the scattered light field. Through stitching and inverse Fourier transform of the scattered light field information in the three-dimensional frequency domain, the three-dimensional reconstruction of the sample's internal structure can be effectively achieved. The generated light intensity diffraction tomography image has high resolution and accuracy, clearly displaying the three-dimensional distribution of minute structures and complex morphologies within the sample. Due to the full utilization of phase and scattered light field information, the light intensity diffraction tomography image of this embodiment often outperforms imaging methods based solely on light intensity in terms of contrast, and can more clearly distinguish the differences between different components or structures within the sample.

[0079] In some embodiments, the step of obtaining the complex amplitude at the sample using the Kramers-Kronig relation may specifically include: By adjusting the voltage of the galvanometer to change the angle of the incident light, the illumination matching conditions are met, and intensity maps under different incident angle conditions are obtained. The phase map of the sample is obtained from the intensity map using the Kramers-Kronig relationship, thereby obtaining the complex amplitude at the sample.

[0080] In this embodiment, a flexible and efficient beam control method is employed: the angle of the incident light is precisely controlled by adjusting the galvanometer voltage. The mirror angle changes with the voltage, thereby altering the direction of the incident light and achieving illumination at different angles. This method allows for rapid dynamic adjustment of the beam to meet illumination matching conditions, facilitating the acquisition of intensity maps under different incident angles. By changing the incident light angle and utilizing the Kramers-Kronig relationship, this embodiment can obtain phase and intensity information of the sample under different illumination conditions, thus yielding more comprehensive complex amplitude information.

[0081] In this application example, intensity diffraction tomography can be used for image reconstruction using the two-dimensional Kramers-Kronig relation. The Kramers-Kronig relation describes a complex function. The mapping relationship between the real and imaginary parts is as follows: ; in The imaginary part of the function. Pi Cauchy principal value, Let be the real part of the function.

[0082] When the illumination matching condition is met, the phase diagram of the light field can be recovered from the intensity diagram. The refractive index can then be recovered using optical scattering theory (Born approximation or Rytov approximation). Initially, the motorized aperture is closed, the imaging objective is switched to a low-power objective (e.g., 10x), and focusing is performed. Although the Kramers-Kronig relation can directly recover the phase of the light field from the intensity diagram, the illumination matching condition is a stringent requirement.

[0083] Please see Figure 3 , Figure 3 This is a schematic diagram of the spectrum of light intensity diffraction tomography provided in the embodiment of the present invention when the illumination matching condition is met. The two circles on the left and right are the sample frequency domain information and its conjugate terms extracted by the objective lens, respectively.

[0084] Figure 3It is received through an industrial camera. The spectrum circle of the incident light field after being truncated by the imaging objective NA is exactly tangent to its conjugate term. At this point, the phase information can be solved from the light field intensity.

[0085] Theoretically, the bias voltage of a dual-axis scanning galvanometer has a linear mapping relationship with the angle of the incident wave vector. However, in actual systems, due to aberrations and the offset between the actual and ideal systems, the bias voltage of the dual-axis scanning galvanometer cannot be directly determined by establishing a linear mapping relationship. To solve this problem, this embodiment uses incident wave vector optimization to determine the voltage value corresponding to the theoretical incident wave vector. Specifically, the bias voltage of the dual-axis scanning galvanometer is changed, the corresponding intensity image is obtained, and a Fourier transform is performed on the intensity image. Then, a Hough circle operation is performed on the frequency domain image of the intensity.

[0086] Hough circle detection is an image detection method based on the Hough transform, used to identify circular contours in images. Its core idea is to map edge points in the image to a parameter space and determine the center and radius of the circle through a voting mechanism.

[0087] Specifically, the mathematical equation of a circle includes the coordinates of its center. and radius Since there are three unknown parameters, a three-dimensional parameter space needs to be constructed. During detection, edge points are first extracted from the image using edge detection (such as the Canny algorithm), and the gradient direction of each edge point is calculated (e.g., using the Sobel operator). Because the center of the circle is usually located along the gradient direction of the edge points, possible center positions can be traversed within a certain radius along this direction, and a vote value is accumulated for each candidate circle parameter in the parameter space. Finally, the position with the highest number of votes in the parameter space (i.e., the accumulator peak) corresponds to the most likely circle in the image.

[0088] This method reduces the computational cost by narrowing the search range through gradient direction, but it is sensitive to noise and requires a preset radius range. In practical applications, it is often combined with multi-scale strategies or probabilistic optimization to improve efficiency.

[0089] The center and radius of the circle are determined, with the center representing the component of the incident wave vector in the xy plane. Then, a linear mapping relationship is established between the bias voltage of the dual-axis scanning mirror 4 and the incident wave vector.

[0090] Please see Figure 4 , Figure 4 This is a flowchart of the galvanometer optimization algorithm based on frequency domain analysis provided in an embodiment of the present invention to meet the lighting matching conditions.

[0091] This embodiment describes the process of obtaining a specific incident wave vector by adjusting the galvanometer voltage. The specific steps are as follows: First, slightly change the galvanometer voltage and obtain the corresponding incident wave vector through the frequency domain plot of the intensity map; then, establish a linear mapping relationship between the voltage value and the incident wave vector; finally, determine the corresponding incident wave vector according to the required number of images. Based on the mapping relationship established above, the solution can be obtained directly. corresponding As the initial solution; finally, solve for the solution. The voltage corresponding to the theoretical value of the wave vector is obtained.

[0092] Specifically, the value of the incident wave vector is determined based on the required number of incident angles N. To satisfy the illumination matching condition, the value of the incident wave vector is: .

[0093] Where NA is the numerical aperture value of the objective lens. This is the theoretical value of the incident wave vector. Let be the wave vector of the incident light in the air. For the first The angle is the angle between the projection of the incident wave vector onto the xy plane and the x-axis.

[0094] Based on the theoretical value of the incident wave vector, the following function is constructed: .

[0095] in, This is the bias voltage of the dual-axis scanning galvanometer. The incident wave is a theoretical value. Based on the bias voltage of the axis scanning galvanometer The measured incident wave vector value. This can be obtained by solving for the minimum value of the above function. get corresponding voltage value .

[0096] Since the above problem is differentiable and has only a unique extremum, the gradient descent algorithm is directly used for optimization. Specifically, the quasi-Newton BFGS algorithm can be used. The initial solution is obtained based on the established linear mapping relationship between the bias voltage of the dual-axis scanning mirror and the incident wave vector.

[0097] Because of each calculation Both involve significant time costs, so before each iteration of optimization, a judgment can be made: if the following conditions are met... They also believe that the conditions are met and no further iteration is needed.

[0098] Repeat the above steps until the theoretical value of each wave vector is determined. corresponding voltage value In this example, as long as the rotating arm of the frame remains unchanged during the process, this value does not need to be updated.

[0099] In the examples of this application, intensity diffraction tomography can perform large-field-of-view global low-resolution imaging, allowing the overall morphology of cells to be seen in the images. Therefore, this method can be used for morphological screening of cells. Furthermore, when observing live cells, the large field of view allows for intuitive selection of cells with good morphology or vigorous vitality for observation. In this dual-modal imaging device, intensity diffraction tomography provides a navigation function.

[0100] For example, the position of the scanning module is first determined, i.e., the dual-axis scanning galvanometer can be conjugate onto the sample surface through the second and third lenses. The computer controls the DAQ to change the voltage of the dual-axis scanning galvanometer, thereby changing the incident angle of the illumination light. The image at this time is captured and subjected to Fourier transform. The magnitude of the incident wave vector is obtained from the Fourier transform. The approximate relationship between the voltage of the dual-axis scanning galvanometer and the incident wave vector is obtained, and then the incident wave vector optimization operation is performed to meet the illumination matching conditions.

[0101] Optionally, the lighting matching conditions are as follows: .

[0102] in, Let be the component of the incident wave vector in the x-direction. Let be the component of the incident wave vector in the y-direction. The numerical aperture of the objective lens. Let be the wave vector of the incident light in the air.

[0103] In some embodiments, the optimization operation of the incident wave vector may include: The frequency domain distribution is obtained by Fourier transforming the sample intensity map, and the center of the diffraction ring is identified using the Hough circle detection algorithm to determine the theoretical value of the incident wave vector. Due to the voltage of the dual-axis scanning galvanometer ) and incident wave vector The relationship is non-linear, and a mapping needs to be established through the following steps: Adjust the galvanometer voltage and acquire the corresponding measured wave vector data; construct an optimization function with the goal of minimizing the wave vector deviation: The voltage parameters were calibrated using an iterative optimization algorithm until the measured wave vector met the illumination matching conditions.

[0104] in, For the first The theoretical values ​​of the x-component of the incident wave vector at various angles. For the first The theoretical values ​​of the y-component of the incident wave vector at various angles. For the first The deflection voltage value of the galvanometer in the x-direction at each angle. For the first The deflection voltage value of the galvanometer in the y-direction at each angle. For the first The actual values ​​of the incident wave vector x component at each angle. For the first The actual values ​​of the incident wave vector y-component at each angle.

[0105] In some embodiments, an iterative optimization algorithm is used to calibrate voltage parameters, specifically including: First, a linear mapping relationship is established between the incident wave vector and the voltage value of the dual-axis scanning galvanometer. The corresponding dual-axis scanning galvanometer voltage is calculated using the required incident wave vector as the initial solution. Then, the mode gradient descent algorithm is used for optimization until the incident wave vector is obtained. equal to theoretical value This satisfies the lighting matching requirements.

[0106] In some embodiments, the step of acquiring an optical diffraction tomography image of a sample may specifically include: A second dataset of the sample is obtained based on illumination light, reference light, and a high-magnification objective lens; a hologram is extracted based on the obtained second dataset, and the complex amplitude information of the sample is recovered from the hologram; the complex amplitude information of the hologram is processed by three-dimensional spectrum stitching and inverse Fourier transform using the relationship between the Rytov approximation field and the scattering potential to generate an optical diffraction tomography image.

[0107] Illumination light is used to illuminate the sample, causing it to scatter light. Reference light then interferes with the scattered light, forming an interference pattern. High-powered objectives provide higher magnification and resolution, enabling the acquisition of finer structural information from the sample. When acquiring a second dataset, high-powered objectives can focus on localized areas of the sample, capturing richer details and minute features.

[0108] By appropriately processing the second dataset, such as through phase extraction and filtering, holograms can be extracted. Recovering the complex amplitude information of the sample from the hologram is one of the key steps in optical diffraction tomography. Complex amplitude information contains both amplitude and phase information of the sample, comprehensively describing its optical properties. Utilizing the interference properties of holograms, the complex amplitude information of the sample can be recovered through mathematical algorithms and optical principles, such as inverse Fourier transform, thus providing data support for subsequent image reconstruction.

[0109] In optical diffraction tomography, the Rytov approximation can be used to approximate complex amplitude information. This processed complex amplitude information is then stitched together in the three-dimensional frequency domain, integrating scattering information from different angles and views to form a complete three-dimensional spectrum. Subsequently, by performing an inverse Fourier transform on the three-dimensional spectrum, the frequency domain information is converted into spatial domain information, ultimately generating an optical diffraction tomography image. This process effectively reconstructs the three-dimensional structure and optical property distribution within the sample, achieving high-resolution, label-free imaging.

[0110] In some embodiments, optical diffraction tomography is used to acquire a second dataset of the sample based on illumination light, reference light, and a high-magnification objective lens. The optical diffraction tomography algorithm includes: Holograms are extracted from the second dataset, and the complex amplitude information of the sample is recovered from the holograms.

[0111] The wave vector of the incident wave is determined based on the phase information in the complex amplitude, and an unwound phase image is generated.

[0112] The calculated amplitude and phase of the sample field and the amplitude and phase of the background field are approximated by Rytov.

[0113] Based on the relationship between the Rytov approximation field and the scattering potential, the refractive index distribution map, i.e., the optical diffraction tomography map, is obtained by splicing three-dimensional spectra and inverse Fourier transform.

[0114] In some embodiments, the step of realizing dual-modal microscopic imaging based on intensity diffraction tomography and optical diffraction tomography may specifically include: In the optical intensity diffraction tomography mode, optical intensity diffraction tomography is performed on the sample to obtain an optical intensity diffraction tomography image; after selecting the target area in the optical intensity diffraction tomography image, the mode is switched to optical diffraction tomography mode; in the optical diffraction tomography mode, optical diffraction tomography is performed on the target area to obtain an optical diffraction tomography image of the corresponding target area.

[0115] In intensity diffraction tomography mode, a low-magnification objective lens is used to image the sample. The low-magnification objective lens provides a large field of view, allowing for rapid acquisition of the overall intensity distribution information of the sample. It also enables the selection of target regions of interest within the intensity diffraction tomography image. This global observation approach is beneficial for identifying local locations within the sample that are of research value or require further analysis.

[0116] After identifying the target area, the system switches to optical diffraction tomography mode. At this point, a high-powered objective lens is used for imaging. This high-powered objective lens offers higher resolution, allowing the system to focus on the target area and capture finer structural details and minute features.

[0117] In this embodiment of the invention, two label-free microscopy techniques—optical diffraction tomography and optical intensity diffraction tomography—are combined. Optical intensity diffraction tomography is used to acquire high-throughput cell refractive index images with a large field of view and low resolution. Then, optical diffraction tomography is used to acquire high-resolution cell refractive index images of local areas with a small field of view. By switching between different modes, label-free refractive index imaging of both the global appearance and local features of the sample can be achieved, realizing dual-modal microscopy imaging.

[0118] For example, firstly, optical intensity diffraction tomography is performed on the sample to observe its morphology with a large field of view and low resolution. If high resolution is required, a specific region is selected in the optical intensity diffraction tomography pattern, and the mode is switched to optical diffraction tomography to perform optical diffraction tomography on that region. The specific switching procedure includes: ① Control the electric displacement stage to move the selected area to the center of the field of view.

[0119] ② Switch the imaging objective from low magnification to high magnification and open the motorized aperture to propagate the reference light.

[0120] ③ Perform optical diffraction tomography. Since this method is three-dimensional imaging, the focal plane shift caused by switching objective lenses can be ignored.

[0121] In the embodiments of this application, when some well-morphologically sound cells are found in the image of optical intensity diffraction tomography (OITD) and further observation is desired, the system can switch to optical diffraction tomography for high-resolution imaging. Cells of interest can be selected in the OITD image, and the computer records the selected position and controls the motorized stage to move it to the corresponding position. Then, the imaging objective is switched to a high-power lens; the motorized aperture is opened, allowing a hologram to be formed on an industrial camera, thus directly obtaining the information of the scattered light field through off-axis holography. Using optical scattering theory, the three-dimensional refractive index map of the sample is reconstructed from the scattered light field information using the Born approximation or the Rytov approximation.

[0122] Please see Figure 5 , Figure 5 This is a schematic diagram of the spectrum of an image obtained using off-axis holography in optical diffraction tomography, as provided in an embodiment of the present invention. The leftmost circle represents the object term, the middle circle represents the zeroth-order term, and the rightmost circle represents the conjugate term.

[0123] As can be seen, to avoid spectral aliasing and achieve off-axis holography, the object term and the zero-order term need to be separated in the frequency domain, resulting in low system spatial bandwidth utilization. Therefore, if the same system switches from a high-power lens to a low-power lens, the size circle of the spectrum captured by the imaging objective (NA) and the maximum frequency that the system can acquire will differ. Figure 5 As shown, therefore, performing off-axis holography under low magnification will result in spectral aliasing.

[0124] Please see Figure 6 , Figure 6 This is a schematic flowchart of a dual-modal imaging system combining optical diffraction tomography and intensity diffraction tomography provided in an embodiment of the present invention.

[0125] First, the appropriate voltage of the galvanometer is determined using the IDT illumination matching procedure to ensure that the illumination light accurately matches the sample requirements, achieving effective illumination matching. Next, the objective lens is switched to low magnification, and the aperture is closed to block the reference light, illuminating the sample only with the illumination light to acquire a large-field-of-view image. Subsequently, the acquired image data is processed using the Kramers-Kronig relation to obtain the IDT image.

[0126] A specific portion is selected from the large field-of-view (IDT) image, and this portion is precisely moved to the center of the field of view by controlling a motorized stage. Finally, the lens is switched to a high-power objective lens, and the aperture is opened to allow the reference light to pass through and interfere with the object light, forming a hologram. By processing the hologram, the scattering field of the sample can be obtained, thus yielding the ODT image.

[0127] Taking cell imaging as an example, in optical intensity diffraction tomography (OITD), the positions of multiple cells are selected and recorded. When the imaging objective is switched to a high-power objective, the computer-controlled motorized stage moves the sample sequentially to the center of the field of view for localized, small-field-of-view, high-resolution OITD imaging. Since both OITD and OITD are label-free, non-invasive imaging methods, they allow for long-term imaging of living cells to observe their life activities. However, not all cells placed in confocal dishes are in optimal health. Direct observation using OITD would be time-consuming, requiring extensive searching for cells. While OITD has lower resolution, it still allows for visualization of cell morphology. Therefore, using OITD for global, large-field imaging as a guide, followed by localized observation using OITD, significantly improves the efficiency of observing living cell life activities.

[0128] On the other hand, embodiments of the present invention also provide an electronic device, please refer to... Figure 7 , Figure 7 This is a schematic diagram of the physical structure of the electronic device provided in the embodiments of the present invention, such as... Figure 7 As shown, the electronic device may include a memory 720, a processor 710, and a computer program stored in the memory 720 and executable on the processor 710. When the processor 710 executes the program, it can implement a dual-modal imaging method, which may include: Two laser beams are generated using a light source system, serving as illumination and reference beams respectively. In the intensity diffraction tomography mode, the illumination beam is turned on, and the motorized aperture is turned off to block the reference beam. The illumination beam passes through the imaging objective (switched to low magnification) via a first path to acquire the intensity diffraction tomography image of the sample. In the optical diffraction tomography mode, the illumination beam is turned on, and the motorized aperture is turned on to allow the reference beam to propagate along a second path. The illumination beam passes through the imaging objective (switched to high magnification) via a first path to acquire the optical diffraction tomography image of the sample. Dual-mode microscopy is achieved based on the intensity diffraction tomography image and the optical diffraction tomography image. The intensity diffraction tomography image is obtained by receiving the scattered light information of the illumination beam through the sample via the low magnification objective; the optical diffraction tomography image is obtained by receiving the scattered light information of the reference beam and the illumination beam through the sample via the high magnification objective.

[0129] Optionally, the electronic device may further include a communication bus 730 and a communication interface 740, wherein the processor 710, the communication interface 740, and the memory 720 communicate with each other through the communication bus 730. The processor 710 can call the computer program in the memory 720 to execute the dual-modal imaging methods provided by the above methods.

[0130] Furthermore, the logical instructions in the aforementioned memory 720 can be implemented as software functional units and, when sold or used as independent products, can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, essentially, or the part that contributes to the prior art, or a part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0131] In another aspect, the present invention also provides a non-transitory computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the dual-modal imaging method provided by the above methods. The steps and principles of the method have been described in detail in the above methods and will not be repeated here.

[0132] Non-transitory computer-readable storage media can be any available medium or data storage device that can be accessed by a processor, including but not limited to magnetic storage (e.g., floppy disks, hard disks, magnetic tapes, magneto-optical disks (MOs), etc.), optical storage (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor storage (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND flash), solid-state drives (SSDs)).

[0133] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0134] Through the above description of the embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus necessary general-purpose hardware platforms, and of course, it can also be implemented by hardware. Based on this understanding, the above technical solutions, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments or some parts of the embodiments.

[0135] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A dual-modal imaging method, characterized in that, include: Two laser beams are generated using a light source system, serving as the illumination beam and the reference beam respectively. In the intensity diffraction tomography mode, the illumination light is turned on, the motorized aperture is turned off to block the reference light, and the illumination light passes through the imaging objective lens, which is switched to a low-power objective lens, in a first path to acquire the intensity diffraction tomography image of the sample. In optical diffraction tomography mode, the illumination light is turned on, the motorized aperture is opened to allow the reference light to propagate along the second path, and the illumination light passes through the imaging objective lens, which is switched to a high-power objective lens, along the first path to acquire the optical diffraction tomography image of the sample. Dual-modal microscopic imaging is achieved based on the intensity diffraction tomography image and the optical diffraction tomography image; The light intensity diffraction tomography image is obtained by receiving the scattered light information of the illumination light through the sample via the low-magnification objective lens; the optical diffraction tomography image is obtained by receiving the scattered light information of the reference light and the illumination light through the sample via the high-magnification objective lens.

2. The dual-modal imaging method according to claim 1, characterized in that, The method for obtaining the optical intensity diffraction tomography image of the sample includes: The illumination light is applied to the sample, and the scattered light information of the illumination light after passing through the sample is received by the low-magnification objective lens in the imaging objective lens and imaged onto an industrial camera to obtain a first imaging dataset; The first imaging dataset is processed using the Kramers-Kronig relation, the Rytov approximation, and the complex deconvolution diffraction tomography 3D reconstruction algorithm to generate the light intensity diffraction tomography image.

3. The dual-modal imaging method according to claim 2, characterized in that, The process of processing the first imaging dataset using the Kramers-Kronig relation, Rytov approximation, and complex deconvolution diffraction tomography 3D reconstruction algorithm to generate the intensity diffraction tomography image includes: The complex amplitude at the sample was obtained using the Kramers-Kronig relation; The scattered light field information of the sample is obtained using the Rytov approximation; The obtained scattered light field information is stitched together in the three-dimensional frequency domain, and the overall frequency domain image is subjected to a three-dimensional inverse Fourier transform to obtain the light intensity diffraction tomography image.

4. The dual-modal imaging method according to claim 3, characterized in that, The method of obtaining the complex amplitude at the sample using the Kramers-Kronig relation includes: By adjusting the voltage of the galvanometer to change the angle of the incident light, the illumination matching conditions can be met, and intensity maps under different incident angle conditions can be obtained. The phase diagram of the sample is obtained from the intensity diagram using the Kramers-Kronig relationship, thereby obtaining the complex amplitude at the sample.

5. The dual-modal imaging method according to claim 4, characterized in that, The lighting matching conditions are met as follows: ; in, Let be the component of the incident wave vector in the x-direction. Let be the component of the incident wave vector in the y-direction. The numerical aperture of the objective lens. Let be the wave vector of the incident light in the air.

6. The dual-modal imaging method according to claim 1, characterized in that, The method for obtaining optical diffraction tomography images of samples includes: A second dataset of the sample is obtained based on the illumination light, the reference light, and the high-magnification objective lens; Holograms are extracted from the obtained second dataset, and the complex amplitude information of the sample is recovered from the holograms. The complex amplitude information of the hologram is processed by three-dimensional spectrum stitching and inverse Fourier transform using the relationship between the Rytov approximation field and the scattering potential to generate the optical diffraction tomography image.

7. The dual-modal imaging method according to claim 1, characterized in that, The dual-modal microscopic imaging based on the intensity diffraction tomography image and the optical diffraction tomography image includes: In the light intensity diffraction tomography mode, light intensity diffraction tomography imaging is performed on the sample to obtain the light intensity diffraction tomography image; After selecting the target region in the optical intensity diffraction tomography image, switch to the optical diffraction tomography mode; In the optical diffraction tomography mode, optical diffraction tomography is performed on the target region to obtain an optical diffraction tomography image corresponding to the target region.

8. A dual-modal imaging system, characterized in that, The dual-modal imaging system using the dual-modal imaging method as described in any one of claims 1 to 7 includes a light source system, a scanning system, and a detection system; The light source system is used to emit collimated polarized light, which is then split into a first laser and a second laser by a first unpolarized beam splitter; the first laser enters the scanning system as illumination light, and the second laser enters the detection system as reference light; The scanning system includes a dual-axis scanning galvanometer and an electrically driven displacement stage; wherein, the dual-axis scanning galvanometer is used to deflect the illumination light to achieve scanning of the sample at different angles; the electrically driven displacement stage is used to place the sample to achieve displacement of the sample in the xy plane; The detection system includes an imaging objective, a second unpolarized beam splitter, an industrial camera, a first reflecting mirror, and a motorized aperture. The imaging objective is used to receive scattered light information from the sample. The second unpolarized beam splitter combines the reference beam and the object beam. The industrial camera is used to receive optical signals for imaging. The motorized aperture is used to control the opening and closing of the reference beam.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and running on the processor, characterized in that, When the processor executes the computer program, it implements the dual-modal imaging method as described in any one of claims 1 to 6.

10. A non-transitory computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the dual-modal imaging method as described in any one of claims 1 to 6.

Images