Optical super-resolution imaging method and apparatus

Abstract

This application provides an optical super-resolution imaging method and apparatus. This method organically integrates light field manipulation and nonlinear effects, possessing both super-diffraction-limited light field focusing capabilities and selective excitation of the resonant modes of the sample to be imaged, thereby achieving deep manipulation of the scattered signal and effective improvement of super-resolution imaging.

Description

Technical Field

[0001] This invention relates to the field of optical imaging technology, and in particular to an optical super-resolution imaging method and apparatus. Background Technology

[0002] In modern scientific research and industrial testing, optical microscopy has become a core tool for micro- and nanoscale observation due to its advantages of being non-destructive and enabling in-situ detection. However, traditional optical imaging is constrained by the diffraction limit, making it difficult to meet the needs of fine observation at even smaller scales and thus hindering the development of related fields.

[0003] Therefore, three main approaches have been developed in existing technologies: electron microscopy, fluorescent labeling, and label-free super-resolution, but all of them have significant limitations:

[0004] 1) Although electron microscopy can achieve nanometer-level resolution, the electron beam is prone to damaging the sample, non-conductive samples require pretreatment, and the operation is complicated and the detection efficiency is low, which cannot be adapted to large-scale rapid in-situ detection.

[0005] 2) Fluorescent labeling super-resolution relies on fluorescent probe labeling. The labeling process may interfere with the intrinsic properties of the sample, and fluorescent molecules are prone to photobleaching, resulting in insufficient imaging stability and limited application scenarios.

[0006] 3) Label-free super-resolution is divided into light field manipulation type and nonlinear effect type. The former relies only on the super-diffraction focusing of the light field itself without combining the sample characteristics, while the latter uses traditional beam excitation and has limited focusing accuracy. The two are used independently without forming a synergy, which makes it difficult to balance imaging resolution and excitation efficiency.

[0007] Therefore, there is an urgent need to develop an innovative technical solution that combines high resolution, non-destructive testing, and wide applicability to break through existing technical bottlenecks. Summary of the Invention

[0008] The purpose of this invention is to overcome the shortcomings of the prior art and provide an optical super-resolution imaging method and apparatus that can take into account high resolution, non-destructive testing and wide applicability.

[0009] The first aspect of this application provides an optical super-resolution imaging method, comprising:

[0010] Generate the initial beam;

[0011] A structured controllable light field is constructed, and the initial beam is processed using the controllable light field to focus the initial beam into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged.

[0012] The excitation beam is incident on the sample to be imaged, and energy is efficiently injected by matching the excitation beam with the target resonance mode of the sample to be imaged.

[0013] The sample to be imaged is excited by the excitation beam to generate resonance, and after absorbing energy, it triggers a local nonlinear effect in the sample to be imaged, causing the sample to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced.

[0014] The superlinear optical signal is acquired and processed by electrical signal to achieve super-resolution imaging that exceeds the diffraction limit.

[0015] Further, as a preferred embodiment, the construction of a structured controllable light field, using the controllable light field to modulate the initial beam so that the initial beam is focused into an excitation beam with super-diffraction-scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged, includes:

[0016] Based on vector diffraction theory or optical superoscillation principle, a structured controllable light field with preset polarization-phase topological characteristics is constructed, wherein the preset polarization-phase topological characteristics match the target resonance mode of the sample to be imaged;

[0017] By loading a phase grayscale image corresponding to the controlled optical field, the wavefront, polarization, and phase of the initial beam are precisely modulated, so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the polarization state and phase structure of the excitation beam are adapted to the target resonance mode of the sample to be imaged, thereby selectively exciting the target resonance mode of the sample to be imaged.

[0018] Further, as a preferred embodiment, the step of incidenting the excitation beam onto the sample to be imaged, and achieving efficient energy injection by adapting the excitation beam to the target resonance mode of the sample to be imaged, includes:

[0019] The propagation direction of the excitation beam is controlled, and the excitation beam is focused and incident on the surface of the sample to be imaged;

[0020] The position of the excitation beam is dynamically adjusted so that the super-diffraction focusing point of the excitation beam is located in different regions of the sample to be imaged, thereby completing a rapid scanning coverage of the sample to be imaged.

[0021] By matching the polarization and phase topology of the excitation beam with the target resonance mode of the sample to be imaged, the energy of the excitation beam is efficiently coupled and absorbed by the sample to be imaged, thus achieving efficient energy injection.

[0022] Further, as a preferred embodiment, the sample to be imaged resonates after being excited by the excitation beam, and after absorbing energy, it induces a local nonlinear effect in the sample, causing it to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced, including:

[0023] The sample to be imaged resonates when excited by the excitation beam.

[0024] The sample to be imaged absorbs the excitation beam through resonance enhancement, which induces a local photothermal nonlinear temperature rise. The complex refractive index of the sample to be imaged changes, causing a continuous shift in the response spectrum, thereby generating a superlinear radiation light signal.

[0025] The sample to be imaged forms an effective response in the high-intensity region at the center of the focal spot where the excitation beam is focused, while the peripheral region of the focal spot remains in the linear response region or the response suppression region, thereby reducing the effective imaging area.

[0026] Further, as a preferred embodiment, the step of acquiring the superlinear optical signal and performing electrical signal processing to complete super-resolution imaging beyond the diffraction limit includes:

[0027] Collect the superlinear optical signal;

[0028] The superlinear optical signal is converted into an electrical signal, and the super-resolution image is reconstructed based on the electrical signal.

[0029] A second aspect of this application provides an optical super-resolution imaging device, comprising:

[0030] Beam generation module, used to generate an initial beam;

[0031] The light field manipulation module is used to construct a structured manipulation light field, and to process the initial beam using the manipulation light field so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged.

[0032] The beam scanning module is used to incident the excitation beam onto the sample to be imaged, and to complete the efficient energy injection by matching the excitation beam with the target resonance mode of the sample to be imaged;

[0033] The signal generation module is used to generate resonance in the sample to be imaged by the excitation beam. After absorbing energy, it induces a local nonlinear effect in the sample to be imaged, causing the sample to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced.

[0034] The signal acquisition module is used to acquire the superlinear optical signal and perform electrical signal processing to complete super-resolution imaging beyond the diffraction limit.

[0035] Furthermore, as a preferred embodiment, the light field modulation module includes:

[0036] The light field construction unit is used to construct a structured and modulated light field with preset polarization-phase topological characteristics based on vector diffraction theory or optical super-oscillation principle. The preset polarization-phase topological characteristics match the target resonance mode of the sample to be imaged.

[0037] The modulation execution unit is used to load a phase grayscale image corresponding to the controlled light field through a spatial light modulator, and to precisely modulate the wavefront, polarization and phase of the initial beam, so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the polarization state and phase structure of the excitation beam are adapted to the target resonance mode of the sample to be imaged, thereby selectively exciting the target resonance mode of the sample to be imaged.

[0038] Further, as a preferred embodiment, the beam scanning module includes:

[0039] A focusing unit is used to control the propagation direction of the excitation beam and focus the excitation beam onto the surface of the sample to be imaged.

[0040] The scanning unit is used to dynamically adjust the position of the excitation beam so that the super-diffraction focusing point of the excitation beam is in different regions of the sample to be imaged, thereby completing a rapid scanning coverage of the sample to be imaged.

[0041] The coupling unit is used to match the polarization and phase topology of the excitation beam with the target resonance mode of the sample to be imaged, so that the energy of the excitation beam is efficiently coupled and absorbed by the sample to be imaged, thus completing the efficient energy injection.

[0042] Further, as a preferred embodiment, the signal generation module includes:

[0043] A resonance unit is used to generate resonance in the sample to be imaged by the excitation beam.

[0044] The radiation unit is used to induce a local photothermal nonlinear temperature rise in the sample to be imaged by resonantly enhancing the absorption of the excitation beam, thereby changing the complex refractive index of the sample to be imaged, causing a continuous shift in the response spectrum, and thus generating a superlinear radiation light signal.

[0045] The response unit is used to enable the sample to form an effective response in the high-intensity region at the center of the focal spot where the excitation beam is focused, while the peripheral region of the focal spot remains in the linear response region or the response suppression region, thereby reducing the effective imaging area.

[0046] Further, as a preferred embodiment, the signal acquisition and processing module includes:

[0047] An optical signal collection unit is used to collect the superlinear optical signal;

[0048] The photoelectric conversion and imaging unit is used to convert the superlinear optical signal into an electrical signal and to perform super-resolution image reconstruction based on the electrical signal.

[0049] The technical solution of this application includes: generating an initial beam; constructing a structured controllable light field, using the controllable light field to process the initial beam so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged; incident the excitation beam onto the sample to be imaged, and complete the efficient energy injection by matching the excitation beam with the target resonance mode of the sample to be imaged; the sample to be imaged is excited by the excitation beam to generate resonance, and after absorbing energy, it induces a local nonlinear effect of the sample to be imaged, causing the sample to radiate a superlinear light signal, and reducing the effective imaging area through the spatial selective enhancement of the superlinear light signal; acquiring the superlinear light signal and performing electrical signal processing to complete super-resolution imaging with super-diffraction limit.

[0050] The technical solution of this application organically integrates optical field manipulation and nonlinear effects, possessing both super-diffraction-limited optical field focusing capabilities and selective excitation of the resonant modes of the sample to be imaged. This achieves deep manipulation of the scattered signal and effective improvement of super-resolution imaging. Furthermore, this application eliminates the need for fluorescent labels and complex pulsed light sources, enabling full-field, non-destructive, in-situ imaging. The system structure is simplified, cost-effective, and fast, exhibiting strong stability and versatility. While ensuring imaging safety and integrity, it significantly improves optical imaging resolution, effectively solving problems such as insufficient resolution, label damage, and system complexity in existing technologies. It possesses extremely high practical value and application prospects. Attached Figure Description

[0051] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0052] Figure 1This is a schematic flowchart illustrating the steps of an optical super-resolution imaging method according to an embodiment of this application;

[0053] Figure 2 This is a schematic diagram of a module of an optical super-resolution imaging device according to an embodiment of this application;

[0054] Figure 3 This is a schematic diagram of the structure of an optical super-resolution imaging device according to an embodiment of this application;

[0055] Figure 4 This is an analytical solution for Mie resonance-enhanced photothermal nonlinear scattering of 85nm silicon nanoparticles in this application and a schematic diagram of the corresponding point spread function reconstruction in the scattering image.

[0056] Figure 5 These are tight-focusing results of an angularly polarized vortex beam with topological charge 1, a radially polarized Laguerre-Gaussian beam with radial quantum number 3 and angular quantum number 1, and a conventional scalar circularly polarized beam constructed based on vector diffraction theory in this application.

[0057] Figure 6 This is a decomposition diagram of the scattering spectra of 85nm silicon nanoparticles under different polarization and topological charge combination light field excitations;

[0058] Figure 7 This is a comparison of the linear point spread function and photothermal nonlinear scattering imaging of the 85nm silicon nanoparticles in this application under different structured light fields;

[0059] Figure 8 This is a schematic diagram of the absorption and scattering spectra of the photothermal properties of the 56nm silicon nanoparticles of this application, as well as the multipolar decomposition of the scattering spectrum.

[0060] Figure 9 This is a comparison of the linear point spread function and photothermal nonlinear scattering imaging of 56nm silicon nanoparticles under different structural light fields according to this application. Detailed Implementation

[0061] To facilitate understanding of the present invention, a more complete description of the invention is provided below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0062] It should be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0063] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0064] Among related technologies, optical microscopy has become a core tool for micro- and nano-scale observation due to its advantages of non-destructive and in-situ detection. However, traditional optical imaging is constrained by the diffraction limit, making it difficult to meet the needs of fine observation at even smaller scales, thus hindering the development of related fields. Electron microscopy super-resolution, fluorescently labeled super-resolution, and label-free super-resolution all have their own limitations. Therefore, there is an urgent need to develop an innovative technical solution that combines high resolution, non-destructive testing, and wide applicability to overcome existing technological bottlenecks.

[0065] Therefore, in order to solve the above-mentioned technical problems, this application provides an optical super-resolution imaging method and corresponding embodiments, which can take into account high resolution, non-destructive testing and wide applicability.

[0066] The technical solution of this application will be described in detail below with reference to the accompanying drawings.

[0067] Figure 1 The diagram shown is a flowchart illustrating the steps of an optical super-resolution imaging method according to an embodiment of this application.

[0068] Please see Figure 1 An optical super-resolution imaging method includes the following steps:

[0069] Step S110: Generate the initial beam.

[0070] It should be noted that in this embodiment, a linearly polarized initial beam is output from a single-wavelength continuous laser, which is then expanded and collimated to form a stable incident beam. This step provides a clean, stable, and power-controllable base light source, providing a reliable input for subsequent precise modulation of the optical field and nonlinear excitation, avoiding the system complexity and excessive cost associated with multi-wavelength or pulsed light sources.

[0071] Step S120: Construct a structured controllable light field and use the controllable light field to process the initial beam so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged.

[0072] It should be noted that in this embodiment, based on the Richards-Wolf vector diffraction theory or the principle of optical super-oscillation, a modulated optical field with a specific polarization-phase topology is designed. The preset polarization-phase topological characteristics are matched with the target resonance mode of the sample to be imaged. By loading the corresponding phase grayscale image, the wavefront, polarization, and phase of the initial beam are precisely modulated, so that the initial beam forms a focal spot smaller than the diffraction limit after focusing, and the polarization and phase of the optical field are matched with the Mie resonance mode of the sample to be imaged. This step can achieve the compression of the first key diffusion function, and at the same time establish the precise matching condition between the optical field and the resonance mode, laying the physical foundation for subsequent efficient energy injection and selective excitation, and breaking through the diffraction limit of traditional Gaussian light from the source end.

[0073] Step S130: The excitation beam is incident on the sample to be imaged, and energy is efficiently injected by matching the excitation beam with the target resonance mode of the sample to be imaged.

[0074] It should be noted that in this embodiment, the position of the excitation beam is dynamically adjusted by controlling the propagation direction of the excitation beam and focusing it onto the surface of the sample to be imaged. This allows the super-diffraction focusing point of the excitation beam to be located in different regions of the sample, achieving rapid scanning coverage of the sample. Utilizing the strong coupling characteristics between the polarization and phase of the excitation beam and the target resonance mode of the sample, the excitation energy is efficiently absorbed by the sample, achieving efficient energy injection. This step ensures rapid scanning imaging while maximizing the coupling of light energy into the target resonance mode, significantly improving the photothermal conversion efficiency and providing sufficient energy for subsequent strong local nonlinear effects.

[0075] Step S140: The sample to be imaged is excited by the excitation beam to generate resonance. After absorbing energy, it induces a local nonlinear effect in the sample to be imaged, causing the sample to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced.

[0076] It should be noted that in this embodiment, the sample to be imaged resonates under resonant excitation. The sample rapidly absorbs the excitation beam non-radiatively and generates a localized, extremely rapid temperature rise. This changes the complex refractive index through the thermo-optic effect, causing a continuous shift in the response spectrum. This shift in the scattering spectrum excites an anti-saturated superlinear optical signal. This signal is significantly enhanced in the high-intensity region at the center of the focal spot where the excitation beam is focused, while the periphery of the focal spot maintains a low response or suppression state. This step enables nonlinear compression of the second key diffusion function, retaining only the effective signal in a very narrow region at the center of the focal spot, significantly reducing the effective imaging area, and breaking the diffraction limit from a physical mechanism perspective.

[0077] Step S150: Acquire superlinear optical signals and perform electrical signal processing to complete super-resolution imaging beyond the diffraction limit.

[0078] It should be noted that in this embodiment, superlinear optical signals are collected, converted into electrical signals, and super-resolution image reconstruction is performed based on the electrical signals. This step can output far-field, label-free, and lossless deep sub-diffraction-limited super-resolution images.

[0079] The following are the core innovative points of the technical solution in this application:

[0080] 1) Optical field manipulation: The core idea of ​​this approach is to generate a super-diffraction-limited focused optical field by modulating the polarization, phase, and amplitude of the initial beam to overcome resolution constraints. Specifically, this can include two techniques: vector optical field manipulation and optical super-oscillation. Vector optical field manipulation relies on the Richards-Wolf vector diffraction theory, which can form extremely small-scale focal spots by controlling the beam's polarization state and phase structure. Optical super-oscillation utilizes the coherent constructive and destructive phases of beams with different spatial frequencies to generate a locally rapidly oscillating ultra-narrow focal spot. Currently, this type of technology focuses on the illumination source itself, relying on the super-diffraction focusing characteristics of the illumination field to achieve resolution improvement. It does not depend on the characteristics of the sample being imaged and is a linear imaging process.

[0081] 2) Super-resolution imaging technology based on optical nonlinear effects. This approach compresses the equivalent point spread function (PSF) through the nonlinear interaction between light and matter, encompassing various mechanisms such as second harmonic generation (SHG), third harmonic generation (THG), stimulated Raman scattering (SRS), four-wave mixing (FWM), and photothermal nonlinear effects. Compared to other nonlinear effects, photothermal nonlinear effects, based on the thermal interaction between light and materials, do not rely on the specific energy level structure or fluorescence properties of the sample, thus having wider applicability. Existing imaging technologies based on photothermal nonlinear effects work by irradiating the sample with an excitation beam. After absorbing the energy of the excitation beam, the sample locally heats up, changing its refractive index through a thermo-optical effect, thereby triggering a shift in the response spectrum and generating a nonlinear scattering signal. Finally, the scattering signal is collected and converted into an electrical signal to complete two-dimensional imaging. However, the current limitation of this type of technology lies in the use of traditional Gaussian light as the excitation source and the focusing spot being a diffraction-limited Airy disk, which limits the focusing accuracy of the excitation light field.

[0082] The technical solution of this application realizes the organic integration of light field manipulation and nonlinear effects, and has both the light field focusing capability beyond the diffraction limit and the selective excitation of the resonance mode of the sample to be imaged, thereby realizing the deep manipulation of the scattering signal and the effective improvement of the super-resolution imaging.

[0083] The technical solution of this application overcomes the limitations of existing label-free super-resolution imaging techniques that rely on the independent application of light field manipulation and nonlinear effects. This technique, through precise design and manipulation of the light field, constructs a stronger local nonlinear response at the sub-diffraction scale. First, by utilizing light field manipulation techniques (such as constructing vector vortex beams and optical super-oscillating beams), a local light field with a lateral size smaller than that of a traditional Gaussian spot can be generated under tight focusing, providing a basis for compressing the initial excitation volume on a physical scale. Second, the unique spatial polarization distribution of the vector light field allows it to selectively and strongly couple with specific Mie resonance modes in the sample to be imaged (such as silicon nanospheres). This selective excitation of modes leads to the efficient injection of incident light energy, resulting in localized light absorption and temperature rise within the nanoscale focal spot. Combined with the superlinear radiation response of the sample to be imaged, this further compresses the point spread function (PSF) of the imaging system, significantly improving imaging resolution while maintaining the advantages of far-field imaging, label-free operation, non-destructive testing, high stability, and reversibility. This method can also be extended to superlinear luminescence response scenarios such as upconversion luminescence in fluorescent systems. This technology utilizes a spatial light modulator (SLM) as an effective means of optical field manipulation, including vector light field manipulation and optical super-oscillation optimization, to generate an extremely small-scale focused light spot, which serves as the excitation light. The technical solution presented in this application significantly improves optical imaging resolution while ensuring imaging security and integrity, effectively solving problems such as insufficient resolution, marker damage, and system complexity in existing technologies. It possesses extremely high practical value and application prospects.

[0084] Furthermore, it should be noted that the technical solution of this application is not limited to nonlinear photoradiation mechanisms without fluorescent labeling. For fluorescent radiation systems, such as the widely used upconversion fluorescence super-resolution imaging mechanism, the super-diffraction focusing light field generated by light field modulation technology can also be used as an excitation source to induce upconversion superlinear fluorescence radiation, further improving the resolution. Upconversion fluorescence refers to the phenomenon that nanoparticles can absorb excitation light with a longer wavelength (lower energy) and, through a specific energy transfer or excited-state transition mechanism, emit light with a shorter wavelength (higher energy).

[0085] Corresponding to the aforementioned embodiments, this application provides an optical super-resolution imaging device and corresponding embodiments.

[0086] Figure 2 The diagram shown is a schematic diagram of an optical super-resolution imaging device according to an embodiment of this application.

[0087] Please see Figure 2 An optical super-resolution imaging device 200 includes: a beam generation module 210, a light field modulation module 220, a beam scanning module 230, a signal generation module 240, and a signal acquisition module 250. Wherein:

[0088] The beam generation module 210 is used to generate an initial beam.

[0089] It should be noted that in this embodiment, the beam generation module 210 includes a single-wavelength continuous laser. The laser can output a linearly polarized initial beam, which, after beam expansion and collimation, forms a stable incident light. This step can provide a pure, stable, and power-controllable basic light source, providing a reliable input for subsequent precise modulation of the optical field and nonlinear excitation, avoiding the system complexity and excessive cost problems caused by multi-wavelength or pulsed light sources.

[0090] The light field manipulation module 220 is used to construct a structured manipulation light field, and to process the initial beam using the manipulation light field so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged.

[0091] Please see Figure 2 Furthermore, in this embodiment, the light field modulation module 220 includes a light field construction unit 221 and a modulation execution unit 222. Wherein:

[0092] The light field construction unit 221 is used to construct a structured controllable light field with preset polarization-phase topological characteristics based on vector diffraction theory or optical super-oscillation principle. The preset polarization-phase topological characteristics match the target resonance mode of the sample to be imaged.

[0093] The modulation execution unit 222 is used to load and control the phase grayscale image corresponding to the light field through the spatial light modulator, and to precisely modulate the wavefront, polarization and phase of the initial beam, so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the polarization state and phase structure of the excitation beam are adapted to the target resonance mode of the sample to be imaged, thereby selectively exciting the target resonance mode of the sample to be imaged.

[0094] It should be noted that, in this embodiment, the modulation execution unit 222 includes a phase-type spatial light modulator (SLM) and a beam splitter (BS). By loading a specific phase grayscale image onto the phase-type spatial light modulator, precise modulation of the initial beam phase is achieved, generating a modulated light field. The modulated beam is incident on the beam splitter, and after transmission through the beam splitter, it enters the beam scanning module 230, where the modulated light field is either a vector light field or an optical super-oscillating light field.

[0095] The beam scanning module 230 is used to incident the excitation beam onto the sample to be imaged, and to complete the efficient energy injection by matching the excitation beam with the target resonance mode of the sample to be imaged.

[0096] Please see Figure 2 Furthermore, in this embodiment, the beam scanning module 230 includes: a focusing unit 231, a scanning unit 232, and a coupling unit 233. Wherein:

[0097] The focusing unit 231 is used to control the propagation direction of the excitation beam and focus the excitation beam onto the surface of the sample to be imaged.

[0098] The scanning unit 232 is used to dynamically adjust the position of the excitation beam so that the super-diffraction focusing point of the excitation beam is in different regions of the sample to be imaged, thereby completing a rapid scanning coverage of the sample to be imaged.

[0099] The coupling unit 233 is used to match the polarization and phase topology of the excitation beam with the target resonance mode of the sample to be imaged, so that the energy of the excitation beam is efficiently coupled and absorbed by the sample to be imaged, thus completing the efficient energy injection.

[0100] It should be noted that in this embodiment, the beam scanning module 230 includes a galvanometer scanning system and an objective lens (Obj). This system can dynamically control the propagation direction of the excitation beam and then guide the excitation beam to the objective lens. The objective lens focuses the excitation beam onto the surface of the sample to be tested. Thus, after phase modulation by the SLM and focusing by the high numerical aperture objective lens, the excitation beam forms a small-scale focused spot in the focal plane that exceeds the diffraction limit. Through the dynamic adjustment of the galvanometer scanning system, the super-diffraction focusing point of the excitation beam can be accurately focused and rapidly scanned to cover different areas of the sample to be imaged.

[0101] The signal generation module 240 excites the sample to be imaged by the excitation beam to generate resonance. After absorbing energy, it induces a local nonlinear effect in the sample to be imaged, causing the sample to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced.

[0102] Please see Figure 2 Furthermore, the signal generation module 240 includes: a resonant unit 241, a radiation unit 242, and a response unit 243. Wherein:

[0103] The resonance unit 241 is used to generate resonance in the sample to be imaged by the excitation beam.

[0104] The radiation unit 242 is used to induce a local photothermal nonlinear temperature rise in the sample to be imaged by resonantly enhancing the absorption of the excitation beam. This changes the complex refractive index of the sample to be imaged, causing a continuous shift in the response spectrum, and thus generating a superlinear radiation light signal.

[0105] The response unit 243 is used to form an effective response in the high-intensity region at the center of the focal spot where the excitation beam is focused, while the peripheral region of the focal spot remains in the linear response region or the response suppression region, thereby reducing the effective imaging area.

[0106] It should be noted that the excitation beam, after being modulated by the optical field, interacts with the sample to be imaged, precisely driving the sample (such as single-crystal silicon nanoparticles in a non-fluorescent system) to a specific Mie resonance mode by means of a matched polarization topological state. Resonant excitation leads to efficient nonradiative absorption and generates localized, extremely rapid nonlinear heating, which changes the material's complex refractive index through thermo-optic effects, causing a continuous shift in the response spectrum. This physical process triggers a strong "anti-saturated superlinear scattering response" in the high-intensity region at the very center of the focused spot, while suppressing the response at the periphery of the spot, thus extremely sharpening (compressing) the effective volume of light-matter interaction in terms of physical dimensions.

[0107] The signal acquisition module 250 is used to acquire superlinear optical signals and perform electrical signal processing to complete super-resolution imaging beyond the diffraction limit.

[0108] Please see Figure 2 Furthermore, the signal acquisition module 250 includes: a light signal collection unit 251 and a photoelectric conversion and imaging unit 252. Wherein:

[0109] The optical signal collection unit 251 is used to collect superlinear optical signals.

[0110] The photoelectric conversion and imaging unit 252 is used to convert superlinear optical signals into electrical signals and to reconstruct super-resolution images based on the electrical signals.

[0111] It should be noted that the signal acquisition module 250 includes a pinhole, a photomultiplier tube (PMT), and a terminal. The superlinear optical signal is collected by the objective lens and transmitted to the galvanometer scanning system. The galvanometer scanning system then guides the signal to the beam splitter, which reflects the response light back to the acquisition optical path. The response light is focused by a lens and passes through the pinhole. Finally, the photomultiplier tube converts the filtered optical signal into an electrical signal, which is then transmitted to the terminal to complete the construction of a two-dimensional super-resolution image of the sample under test.

[0112] It should be noted that the optical super-resolution imaging method implemented by the optical super-resolution imaging device disclosed in this embodiment is the same as that described in the above embodiments, and therefore will not be described in detail here. Optionally, each module and the other operations or functions described above are respectively for implementing the methods in the foregoing embodiments.

[0113] To better understand the technical solution of this application, the principles of the technical solution of this application are explained below with reference to two specific embodiments. When understanding the following two embodiments, please refer to... Figures 3-9 To understand, the following is about Figures 4-9 Detailed supplementary explanations will be provided.

[0114] Figure 4This is an analytical solution for Mie resonance-enhanced photothermal nonlinear scattering of 85nm silicon nanoparticles and a schematic diagram of the corresponding point spread function reconstruction in the scattering image. (ab) shows the distribution of the absorption and scattering cross-sections as a function of particle radius and wavelength obtained from Mie theory, with the 532nm excitation wavelength (dashed lines in a and b) indicating the magnetic dipole (MD), electric dipole (ED), and higher-order modes. (c) shows the steady-state temperature evolution curves of silicon nanospheres with radii of 60, 70, 85, and 112nm under 532nm laser excitation as a function of light intensity. (d-f) show the nonlinear scattering response curves of three typical particle sizes (85nm, 60nm, and 70nm), illustrating the transition from linear response to scattering suppression and then to anti-saturation. (g) shows the evolution of the effective point spread function in different nonlinear regions: ① linear region, ② scattering suppression region (quasi-annular point spread function), ③ anti-saturation region (compressed central peak), ④ sublinear saturation region.

[0115] Figure 5 These are tight-focusing results of an angularly polarized vortex beam with topological charge 1, a radially polarized Laguerre-Gaussian beam with radial quantum number 3 and angular quantum number 1, and a conventional scalar circularly polarized beam constructed based on vector diffraction theory in this application.

[0116] Figure 6 This is a decomposition of the scattering spectra of 85 nm silicon nanoparticles under different polarization and topological charge combinations of optical field excitation (ALL: total scattering, ED: electric dipole, MD: magnetic dipole); (a) circular polarization excitation; (b) pure angular polarization (AP) excitation, dominated by the MD mode; (c) radial polarization (RP) excitation; (d~e) APV excitation (AP loaded with topological charges of l=+1 and l=-1 respectively); (f) RPLG 3,1 excitation;

[0117] Figure 7 This is a comparison of the linear point spread function and photothermal nonlinear scattering imaging under different structured light fields. (a, d, g, j) Normalized point spread function distribution of the linear scattering region under low excitation light intensity; (b, e, h, k) High light intensity (1.9 × 10⁻⁶) 5 W / cm 2 Nonlinear scattering imaging in the anti-saturation region; (c, f, i, l) circularly polarized light, angularly polarized vortex light, RPLG 3,1 Comparison of lateral light intensity profiles under Linear (solid lines) and Nonlinear (dashed lines);

[0118] Figure 8The photothermal properties of 56 nm radius silicon nanoparticles are calculated based on Mie scattering theory. (a) is the absorption and scattering spectrum of this silicon nanoparticle at room temperature. (b) is the superlinear radiation response curve of this silicon nanoparticle at an excitation wavelength of 532 nm. (c) is the multipolar decomposition of the scattering spectrum of 56 nm radius silicon nanoparticles.

[0119] Figure 9 This is a comparison of the linear point spread function and photothermal nonlinear scattering imaging under different structured light fields. (a, d) Normalized point spread function distribution of the linear scattering region under low excitation light intensity; (b, e) High light intensity (2.2 × 10⁻⁶) 5 W / cm 2 (c, f) Nonlinear scattering imaging in the anti-saturation region; (c, f) Comparison of transverse light intensity profiles of circularly polarized light and angularly polarized vortex light under Linear (solid line) and Nonlinear (dashed line) conditions.

[0120] It should be noted that the samples to be imaged in both embodiments are silicon nanoparticles.

[0121] Example 1:

[0122] An analytical model based on Mie theory and combined with the heat conduction equation was established to accurately and quantitatively analyze the photothermal nonlinear scattering effect of spherical silicon nanoparticles, avoiding the computational cost of full-wave numerical simulation. For spherical particles of a given size, the following can be calculated using the Mie scattering theory formula:

[0123] Scattering cross section:

[0124]

[0125] Absorption cross section:

[0126]

[0127] in, , It is the Mie scattering coefficient.

[0128] Furthermore, these cross sections can be decomposed into a superposition of contributions from electric dipoles (ED), magnetic dipoles (MD), and higher-order multipole resonances. According to Mie theory, the optical cross section is determined by the particle size and the complex permittivity of the material. In the visible light band, the complex refractive index of silicon exhibits a significant temperature dependence. Therefore, for particles of a fixed size, their absorption and scattering cross sections become temperature-dependent quantities mediated by the thermal response of the material's permittivity. Under continuous-wave laser excitation, the steady-state temperature rise of a single spherical particle in a homogeneous medium can be expressed as:

[0129]

[0130] in This represents the total power absorbed by the sphere. Indicates the absorption cross section (depending on the excitation wavelength and temperature). Indicates wavelength as The intensity of monochromatic light, Indicates the ambient thermal conductivity. Let represent the radius of the sphere. The calculation is performed using a self-consistent iterative method: [from...] Determine steady-state temperature rise Then by Update material properties until convergence. This method can analytically derive the nonlinear temperature evolution of nanospheres of arbitrary size under arbitrary excitation wavelengths and power densities.

[0131] Based on the above model, the distribution of the absorption and scattering cross-sections of silicon nanoparticles as a function of particle radius and wavelength was plotted through analytical calculations, as follows: Figure 4 As shown in (a) and 4(b), at 532 nm of the excitation beam, different particle sizes determine the degree of spectral overlap between the excitation beam wavelength and the multipole Mie mode supported by the nanospheres. This size-dependent photothermal nonlinear heating effect, in Figure 4 (c) The temperature evolution curve clearly shows that nanoparticles that match the Mie resonance (such as those with radii of 60 nm, 85 nm, and 112 nm) exhibit a rapid nonlinear increase in temperature with increasing excitation light intensity due to enhanced absorption, while particles that deviate from the resonance (such as those with 70 nm) show an almost linear thermal response.

[0132] In sync with the nonlinear temperature rise caused by the increase in incident light intensity, the scattering cross section of the nanoparticles is significantly modulated, resulting in a nonlinear response in the scattered light intensity. Figure 4 (d)~(f) show three typical nonlinear scattering behaviors. In this example, 85nm particles were selected as the sample to be imaged. Their scattering characteristics exhibited a pattern of first decreasing and then increasing, showing an overall superlinear trend, which is suitable for our imaging scheme. Figure 4 (d): Under low light intensity, the scattering response is linear; as light absorption causes the temperature to rise, the thermo-optical effect causes the refractive index change to cause the particles to deviate from the Mie resonance and enter the "suppression region" (state ②) where the scattering efficiency decreases; when the light intensity is further increased (which can only be achieved in the central region of the focal spot), the scattering cross section recovers and enters the "anti-saturation" or superlinear region (state ③).

[0133] Figure 4(g) Visually demonstrates the spatial modulation effect of this nonlinear effect on the effective point spread function: in the scattering suppression region, the point spread function forms a ring-like depletion region; however, when the anti-saturation light intensity threshold is reached (state ③), the point spread function produces a sharp and isolated central maximum, with its width significantly reduced, providing a basis for achieving positioning accuracy far exceeding the optical diffraction limit. Conversely, particles exhibiting only a saturation effect (such as 60 nm, Figure 4 (e) will cause the point spread function to broaden (state ④), which is not conducive to improving resolution.

[0134] Photothermal nonlinearity provides a physical mechanism for the reshaping and compression of the point spread function, while the spatial profile and polarization state of the initial focal spot are equally crucial for improving resolution. Unlike the traditional Gaussian beam commonly used in confocal photothermal imaging, a modulated vector light field is used as a customized excitation source and focused through a high numerical aperture objective lens. In practice, MATLAB software is used in advance on the computer to simulate and calculate the focusing distribution and various polarization components of different structured light fields based on Richards-Wolf vector diffraction theory. After obtaining the theoretical phase distribution of the target light field, it is converted into a specific 8-bit grayscale image (grayscale values ​​0-255 are mapped to a phase delay of 0-2π) for subsequent loading into the SLM. The Richards-Wolf theory considers the vector characteristics of the amplitude, phase, and polarization of light waves under high numerical aperture, and can accurately predict the electromagnetic field distribution on the focal plane. Figure 5 This embodiment demonstrates the application of Richards-Wolf vector diffraction theory to the polarization of conventional scalar circularly polarized beams (CP), angularly polarized vortex beams (APV) with topological charges, and higher-order radially polarized beams (RPLG). 3,1 The calculation results of the tight-focusing characteristics. For example... Figure 5 As shown in (a), RPLG 3,1 The beam produces the smallest full width at half maximum (FWHM) focal spot, followed by the angularly polarized vortex beam with first-order topological charge, both of which are significantly better than standard circularly polarized light.

[0135] However, the interaction between the vector field and the nanosphere is not determined solely by the focal spot size, but also largely depends on mode matching. Figure 6(a) to (f) detail the multipolar decomposition results of the scattering spectra of 85 nm silicon nanospheres under different excitation conditions, showing that the excitation of Mie resonance is strictly controlled by local polarization matching. For a standard angularly polarized (AP) beam, its focal field is essentially the interference superposition of left-handed and right-handed circularly polarized components; along the optical axis, the longitudinal electric field components of these two spin states have equal amplitudes and opposite phases, resulting in complete destructive interference. This characteristic of zero light intensity at the optical axis center makes the excitation of electric multipolar modes negligible, while its angular distribution can effectively induce a strong longitudinal magnetic field (Hz), thereby achieving strong magnetic mode excitation. By superimposing orbital angular momentum (OAM), specifically by introducing topological charges (l=±1) to form an angularly polarized vortex beam, the symmetry of the topological charge distribution of the left-handed and right-handed circularly polarized components is broken. This symmetry breaking prevents the complete cancellation of the central field (e.g., Figure 6 As shown in (d~e), the beam can simultaneously support both electric and magnetic resonance. Therefore, the multipole composition under angularly polarized vortex excitation is highly similar to that of standard circularly polarized light. The recovery of the electric dipole response under 532 nm excitation is crucial for matching the target photothermal nonlinear process.

[0136] Similarly, radially polarized (RP) light and RPLG 3,1 The beam intrinsically generates a strong longitudinal electric field at the focal spot. Figure 5 This makes it naturally suitable for exciting electric dipole modes and suppressing magnetic dipole modes. This analysis confirms that by controlling the polarization and phase topology of the incident beam, selective excitation of specific multipole modes can be achieved without altering the particle geometry. Based on this, this example will subsequently select CP, APV, and RPLG. 3,1 These three beams serve as excitation light for 85nm particles.

[0137] This example uses, for example Figure 3The optical super-resolution imaging device shown is a 532nm continuous laser used as the excitation source, and a high numerical aperture (NA=0.9) focusing objective lens. The linearly polarized beam output from the laser, after beam expansion and collimation, illuminates the liquid crystal panel of the spatial light modulator (SLM) at a very small incident angle (less than 5°). When the linearly polarized light is incident on the SLM, the birefringence effect of the liquid crystal molecules introduces a corresponding phase delay to the beam wavefront according to the gray values ​​of each pixel in the pre-loaded phase grayscale image in the SLM. In this way, well-controlled advanced structured light can be flexibly generated. Subsequently, the modulated beam passes through a beam splitter and enters a galvanometer scanning system. The galvanometer system controls the beam propagation direction for dynamic two-dimensional scanning, and finally, it is focused by a microscope objective onto the surface of an 85nm silicon nanoparticle sample. The silicon nanoparticles are located on the substrate surface and are in the air. At this point, the energy of the laser beam is absorbed by the silicon nanoparticles. When the excitation light intensity reaches 1.9 × 10⁵ W / cm², a compressed superlinear scattering response signal is obtained. Subsequently, the scattering signal of the sample is collected by the same objective lens, reflected by a dichroic mirror / beam splitter, and then received by a detector (such as a photomultiplier tube or avalanche photodiode) and converted into an electrical signal, which is finally transmitted to a computer for image reconstruction. The final imaging effect is as follows. Figure 7 As shown, the RPLG with the smallest intrinsic focal spot can be observed. 3,1 The nonlinearity of the beam and photothermal properties compresses the full width at half maximum (FWHM) of the imaging from 228 nm in the linear region to approximately 42 nm. This corresponds to a spatial resolution of approximately λ / 12, representing a significant breakthrough in label-free imaging resolution.

[0138] Example 2

[0139] In this example, a 56 nm particle was selected as the sample. Based on Mie theory and combined with an analytical model of the heat conduction equation, the distribution of its scattering and absorption cross-sections with wavelength can be obtained as follows: Figure 8 As shown in (a), although the resonance peak does not exactly match the wavelength of 532 nm, as the temperature increases, the spectrum gradually redshifts, eventually causing it to match the resonance peak. Therefore, as shown in (a), the resonance peak will appear as follows. Figure 8 (b) shows a continuously increasing superlinear response. Predictably, this response will also have a certain compressive effect on the PSF of the focused spot. Figure 8 (c) shows the multi-level decomposition of the scattering spectrum of a 56 nm radius silicon nanoparticle. It can be seen that, unlike the 85 nm radius silicon nanospheres, this particle matches to the MD mode near the excitation wavelength of 532 nm. Therefore, for RPLGs that cannot be excited to the MD mode... 3,1 The light beam is no longer suitable for exciting this particle. Therefore, in this example, CP and APV beams will be selected as the excitation light for the 56nm particle.

[0140] This example also uses the following... Figure 3The super-resolution localization imaging device shown is a 532nm continuous laser used as the excitation source, and a high numerical aperture (NA=0.9) focusing objective lens. The linearly polarized beam output from the laser, after beam expansion and collimation, illuminates the liquid crystal panel of the spatial light modulator (SLM) at a very small incident angle (less than 5°). When the linearly polarized light is incident on the SLM, the birefringence effect of the liquid crystal molecules introduces a corresponding phase delay to the beam wavefront according to the gray values ​​of each pixel in the pre-loaded phase grayscale image in the SLM. In this way, well-controlled advanced structured light can be flexibly generated. Subsequently, the modulated beam passes through a beam splitter and enters a galvanometer scanning system. The galvanometer system controls the beam propagation direction for dynamic two-dimensional scanning, and finally, it is focused by a microscope objective onto the surface of a 56nm silicon nanoparticle sample. The silicon nanoparticles are located on the substrate surface and are in the air. At this point, the energy of the laser beam is absorbed by the silicon nanoparticles. When the excitation light intensity reaches 2.2 × 10⁵ W / cm², a compressed superlinear scattering response signal is obtained. Subsequently, the scattering signal of the sample is collected by the same objective lens, reflected by a dichroic mirror / beam splitter, and then received by a detector (such as a photomultiplier tube or avalanche photodiode) and converted into an electrical signal, which is finally transmitted to a computer for image reconstruction. The final imaging effect is as follows. Figure 9 As shown, the photothermal nonlinearity compresses the full width at half maximum (FWHM) of the imaging PSF of the APV beam from 282 nm in the linear region to approximately 155 nm, which is much smaller than the corresponding diffraction limit of 296 nm.

[0141] The two specific embodiments listed above demonstrate that this application has the following technical effects:

[0142] 1. Achieved high spatial resolution at the deep sub-diffraction limit: This invention breaks through the bottleneck of traditional nonlinear imaging resolution being limited by the initial excitation spot size. It organically combines the physical compression of the focal spot size brought about by the advanced structured light field with the compression of the imaging PSF brought about by the superlinear scattering response, achieving a significant improvement in the system resolution of the far-field markerless optical imaging system. Calculations show that this invention can compress the full width at half maximum (FWHM) limit of imaging to approximately 42 nm (approximately lambda / 12), achieving a step-wise improvement in resolution under far-field conditions.

[0143] 2. Precise selective excitation of multipole resonant modes: This invention achieves selective excitation of multipole resonant modes through precise design of the polarization state and phase topology of the incident light field. This pioneering mechanism ensures the applicability of the photothermal nonlinear response trajectory based on analytical theory in complex structured light fields.

[0144] 3. High system compatibility and technological versatility: This invention utilizes a spatial light modulator (SLM) to generate and control the beam, exhibiting fast dynamic response. It seamlessly integrates with and switches between various advanced light fields (such as APV, RPLG, and optical super-oscillation) simply by modifying the phase grayscale image via software. Furthermore, this mechanism, based on the synergy of mode matching and superlinear response, is not only applicable to semiconductor nanoparticles such as silicon in non-fluorescent systems but can also be extended to superlinear luminescence response scenarios such as upconversion luminescence in fluorescent systems, making its applicability extremely broad.

[0145] 4. This invention enables rapid, label-free, and non-destructive in-situ detection in the far field, greatly simplifying the system and reducing costs: It employs a single-wavelength continuous-wave (CW) laser confocal microscopy combined with a GalvanoScanning system for rapid two-dimensional coverage scanning, resulting in a flexible and efficient system architecture. It eliminates the need for complex dual-beam or pulsed laser systems (such as STED microscopes), significantly simplifying hardware complexity and reducing experimental costs. Furthermore, in non-fluorescent systems, no fluorescent probe labeling is required, avoiding the "photobleaching" problem of fluorescent molecules and preventing irreversible damage to the sample (such as gold sputtering or electron beam bombardment in electron microscopy), thus offering extremely high safety, reliability, and imaging reversibility.

[0146] The various embodiments of this application have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is chosen to best explain the principles, practical application, or improvement of the technology in the market, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. An optical super-resolution imaging method, characterized in that, include: Generate the initial beam; A structured controllable light field is constructed, and the initial beam is processed using the controllable light field to focus the initial beam into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged. The excitation beam is incident on the sample to be imaged, and energy is efficiently injected by matching the excitation beam with the target resonance mode of the sample to be imaged. The sample to be imaged is excited by the excitation beam to generate resonance, and after absorbing energy, it triggers a local nonlinear effect in the sample to be imaged, causing the sample to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced. The superlinear optical signal is acquired and processed by electrical signal to achieve super-resolution imaging that exceeds the diffraction limit.

2. The optical super-resolution imaging method according to claim 1, characterized in that, The construction of a structured, modulated optical field, which modulates the initial beam to focus it into an excitation beam with super-diffraction-scale focusing characteristics, and the excitation beam selectively excites the target resonance mode of the sample to be imaged, includes: Based on vector diffraction theory or optical superoscillation principle, a structured controllable light field with preset polarization-phase topological characteristics is constructed, wherein the preset polarization-phase topological characteristics match the target resonance mode of the sample to be imaged; By loading a phase grayscale image corresponding to the controlled optical field, the wavefront, polarization, and phase of the initial beam are precisely modulated, so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the polarization state and phase structure of the excitation beam are adapted to the target resonance mode of the sample to be imaged, thereby selectively exciting the target resonance mode of the sample to be imaged.

3. The optical super-resolution imaging method according to claim 1, characterized in that, The step of incidenting the excitation beam onto the sample to be imaged, and achieving efficient energy injection by matching the excitation beam with the target resonance mode of the sample to be imaged, includes: The propagation direction of the excitation beam is controlled, and the excitation beam is focused and incident on the surface of the sample to be imaged; The position of the excitation beam is dynamically adjusted so that the super-diffraction focusing point of the excitation beam is located in different regions of the sample to be imaged, thereby completing a rapid scanning coverage of the sample to be imaged. By matching the polarization and phase topology of the excitation beam with the target resonance mode of the sample to be imaged, the energy of the excitation beam is efficiently coupled and absorbed by the sample to be imaged, thus achieving efficient energy injection.

4. The optical super-resolution imaging method according to claim 1, characterized in that, The sample to be imaged resonates upon excitation by the excitation beam, absorbing energy and triggering a local nonlinear effect, causing it to radiate a superlinear optical signal. Through the spatial selective enhancement of this superlinear optical signal, the effective imaging area is reduced, including: The sample to be imaged resonates when excited by the excitation beam. The sample to be imaged absorbs the excitation beam through resonance enhancement, which induces a local photothermal nonlinear temperature rise. The complex refractive index of the sample to be imaged changes, causing a continuous shift in the response spectrum, thereby generating a superlinear radiation light signal. The sample to be imaged forms an effective response in the high-intensity region at the center of the focal spot where the excitation beam is focused, while the peripheral region of the focal spot remains in the linear response region or the response suppression region, thereby reducing the effective imaging area.

5. The optical super-resolution imaging method according to claim 1, characterized in that, The acquisition of the superlinear optical signal and the processing of the electrical signal to achieve super-resolution imaging beyond the diffraction limit include: Collect the superlinear optical signal; The superlinear optical signal is converted into an electrical signal, and the super-resolution image is reconstructed based on the electrical signal.

6. An optical super-resolution imaging device, characterized in that, include: Beam generation module, used to generate an initial beam; The light field manipulation module is used to construct a structured manipulation light field, and to process the initial beam using the manipulation light field so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the excitation beam can selectively excite the target resonance mode of the sample to be imaged. The beam scanning module is used to incident the excitation beam onto the sample to be imaged, and to complete the efficient energy injection by matching the excitation beam with the target resonance mode of the sample to be imaged; The signal generation module is used to generate resonance in the sample to be imaged by the excitation beam. After absorbing energy, it induces a local nonlinear effect in the sample to be imaged, causing the sample to radiate a superlinear optical signal. Through the spatial selective enhancement of the superlinear optical signal, the effective imaging area is reduced. The signal acquisition module is used to acquire the superlinear optical signal and perform electrical signal processing to complete super-resolution imaging beyond the diffraction limit.

7. The optical super-resolution imaging device according to claim 6, characterized in that, The light field modulation module includes: The light field construction unit is used to construct a structured and modulated light field with preset polarization-phase topological characteristics based on vector diffraction theory or optical super-oscillation principle. The preset polarization-phase topological characteristics match the target resonance mode of the sample to be imaged. The modulation execution unit is used to load a phase grayscale image corresponding to the controlled light field through a spatial light modulator, and to precisely modulate the wavefront, polarization and phase of the initial beam, so that the initial beam is focused into an excitation beam with super-diffraction scale focusing characteristics, and the polarization state and phase structure of the excitation beam are adapted to the target resonance mode of the sample to be imaged, thereby selectively exciting the target resonance mode of the sample to be imaged.

8. The optical super-resolution imaging device according to claim 7, characterized in that, The beam scanning module includes: A focusing unit is used to control the propagation direction of the excitation beam and focus the excitation beam onto the surface of the sample to be imaged. The scanning unit is used to dynamically adjust the position of the excitation beam so that the super-diffraction focusing point of the excitation beam is in different regions of the sample to be imaged, thereby completing a rapid scanning coverage of the sample to be imaged. The coupling unit is used to match the polarization and phase topology of the excitation beam with the target resonance mode of the sample to be imaged, so that the energy of the excitation beam is efficiently coupled and absorbed by the sample to be imaged, thus completing the efficient energy injection.

9. The optical super-resolution imaging device according to claim 6, characterized in that, The signal generation module includes: A resonance unit is used to generate resonance in the sample to be imaged by the excitation beam. The radiation unit is used to induce a local photothermal nonlinear temperature rise in the sample to be imaged by resonantly enhancing the absorption of the excitation beam, thereby changing the complex refractive index of the sample to be imaged, causing a continuous shift in the response spectrum, and thus generating a superlinear radiation light signal. The response unit is used to enable the sample to form an effective response in the high-intensity region at the center of the focal spot where the excitation beam is focused, while the peripheral region of the focal spot remains in the linear response region or the response suppression region, thereby reducing the effective imaging area.

10. The optical super-resolution imaging device according to claim 7, characterized in that, The signal acquisition and processing module includes: An optical signal collection unit is used to collect the superlinear optical signal; The photoelectric conversion and imaging unit is used to convert the superlinear optical signal into an electrical signal and to perform super-resolution image reconstruction based on the electrical signal.

Images