Far-field super-resolution imaging method and device based on light field scattering and autocorrelation

Abstract

The invention provides a far-field super-resolution imaging method and device based on light field scattering and autocorrelation. The imaging device comprises a laser, a phase modulator, a scattering sheet, an imaging lens, a charge coupled device (CCD) and a computer. Light beams emitted by the laser uniformly irradiate the phase modulator, a time-varying speckle field is generated and irradiates an object to be measured, information of a light field penetrating through the object to be measured is freely transmitted to the scattering sheet, the scattered light field is imaged on the CCD through the lens, and the CCD records spatial intensity distribution information of the scattered light field and stores the spatial intensity distribution information in the computer. The laser, the phase modulator and the CCD are synchronously triggered and controlled by a synchronous signal generator to work, and the scattering sheet plane, the lens plane and the CCD plane meet the imaging relation. Fourier transform atlas information of an object to be measured is obtained by carrying out correlation operation on space intensity distribution information recorded by a CCD, and then phase recovery reconstruction is carried out on the atlas information to obtain real space image information of the object to be measured.

Description

Technical Field

[0001] The present invention relates to a far-field super-resolution imaging method and device based on light field scattering and autocorrelation, belonging to the technical field of optical imaging. Background Art

[0002] For applications such as remote sensing satellite imaging, biological microscopy, and medical tissue imaging, obtaining high-resolution images of target scenes can improve target recognition accuracy, tissue structure analysis, and disease diagnosis accuracy, thus possessing significant application value. However, in actual applications, due to limitations imposed by the optical diffraction limit of the system, the imaging resolution often fails to meet practical application requirements. Therefore, it is necessary to develop new technologies and methods for far-field super-resolution imaging that break through the optical diffraction limit of the system.

[0003] Currently, there are two main types of far-field super-resolution imaging technologies. One is to improve the resolution of the imaging system through reconstruction algorithms, such as traditional deconvolution techniques, compressed sensing algorithms based on sparse priors, and deep learning algorithms. However, such methods often require long iterations and have high detection signal-to-noise ratio requirements, resulting in slow imaging speeds and limited super-resolution capabilities. The other is to achieve super-resolution imaging by physically acquiring weaker high-frequency information corresponding to the target scene through innovations in structured lighting and detection methods, such as synthetic aperture imaging, Fourier stack imaging, coherent diffraction imaging, and scattering imaging. However, such methods also have corresponding drawbacks. For example, synthetic aperture imaging technology is highly dependent on phase stability and is susceptible to environmental disturbances. Fourier stacking technology requires the acquisition of a large number of low-resolution images at different illumination angles, which is data-intensive and time-consuming, and the illumination angle range and step accuracy directly affect the resolution improvement capability. Scattering imaging technology requires precise measurement and calibration of the transmission matrix, which is often time-consuming and requires high system stability. Recalibration is required after the scattering medium is replaced. Although the combination of coherent diffraction imaging and scattering media can achieve super-resolution imaging, its super-resolution imaging is achieved at the expense of the imaging field of view. It requires the use of additional Fourier stacking technology to scan the object to achieve a large field of view, and the scattering plate needs to be placed in the far field of the object, which is obviously difficult to achieve for larger detection targets (see the literature: Super-resolution imaging with large field of view for distant objects through scattering media [J]. Optics and Lasers in Engineering, 2023, 164: 107502). In general, this type of method has the problems of relatively complex systems and strong dependence on the environment. Therefore, it is necessary to provide a new super-resolution imaging method with a simple structure and the ability to significantly improve imaging resolution. Summary of the Invention

[0004] The purpose of the present invention is to address the shortcomings of existing far-field super-resolution imaging technology and provide a far-field super-resolution imaging method and device with a simple system, a simple reconstruction algorithm and strong super-resolution capability by combining the scattered light field and the high-order correlation characteristics of the light field.

[0005] The technical solution for achieving the purpose of the present invention is to provide a far-field super-resolution imaging device based on light field scattering and autocorrelation, which includes a laser, a phase modulator, a scattering plate, a lens, a charge-coupled device (CCD), and a computer. The laser, phase modulator, and charge-coupled device (CCD) are synchronously triggered and controlled by a synchronization signal generator to operate. The light beam emitted by the laser irradiates the phase modulator, which generates a time-varying speckle field that irradiates the object to be measured. The light intensity information transmitted by the object to be measured is freely transmitted to the scattering plate. The light field information scattered by the scattering plate is imaged on the charge-coupled device (CCD) through the lens. The spatial intensity distribution information of the scattered light field is recorded by the CCD and stored in the computer. A high-resolution real-space image of the object to be measured is obtained through correlation operation and image reconstruction processing.

[0006] The present invention discloses a far-field super-resolution imaging device based on light field scattering and autocorrelation, wherein the scattering plate plane, the lens and the charge-coupled device (CCD) plane constitute a single-lens imaging system with a magnification of 1 / M, where M>1; the spatial resolution of the imaging system at the scattering plate is less than 1 / 2 of the spectral resolution of the object to be measured at the scattering plate plane.

[0007] The correlation length l of the scattering plate c Smaller than the spectral resolution of the object to be measured in the scattering plane.

[0008] The light-clearing aperture of the scattering plate meets the constraint conditions: the light-clearing aperture is larger than the light-clearing aperture of the lens, the maximum light-clearing aperture is less than M times the CCD detection aperture, M is the inverse of the magnification of the imaging system, and the minimum light-clearing aperture is larger than the CCD detection aperture, so as to achieve far-field super-resolution imaging, and the magnification of super-resolution imaging is proportional to the light-clearing aperture of the scattering plate.

[0009] The technical solution of the present invention also includes a far-field super-resolution imaging method based on light field scattering and autocorrelation, which comprises the following steps: (1) Acquisition of detection signals of the object to be measured The laser, phase modulator, and charge-coupled device (CCD) are triggered and controlled by a synchronous signal generator. The laser beam irradiates the phase modulator, which generates a time-varying speckle field that irradiates the object to be measured. After the light intensity information transmitted by the object to be measured freely propagates to the scattering plate, the scattered light field information scattered by the scattering plate is imaged on the charge-coupled device (CCD) through a lens. The spatial intensity distribution information of the scattered light field recorded by the CCD is stored in a computer. (2) Extraction of Fourier transform spectrum image of the object to be tested The charge coupled device CCD collects and records a total of S instantaneous light intensity spatial distribution images, and the corresponding kth instantaneous light intensity spatial distribution image is recorded as I k(m,n),k=1,2,......,S; where m and n represent the horizontal and vertical pixel positions of the recorded image respectively; perform correlation operation on the spatial intensity distribution information recorded by the charge coupled device (CCD) according to the following formula to obtain the Fourier transform spectrum image of the object to be measured information: Where: M and N are the total number of horizontal and vertical pixels of the image recorded by the charge coupled device CCD; (3) High-resolution image reconstruction of the object to be measured The Fourier transform spectrum image of the object to be measured is obtained by using the phase recovery algorithm Reconstruction is performed to obtain a high-resolution real-space image of the object to be measured.

[0010] Compared with the prior art, the present invention has the following technical effects:

[0011] 1. The present invention adopts the light field scattering effect of static scattering medium and the autocorrelation imaging scheme, so the system structure is simple and the cost is low. Its spatial resolution is related to the aperture of the scattering sheet, and there is no need to process a large-aperture lens system.

[0012] 2. Since the present invention adopts the light field scattering effect of the static scattering medium and the autocorrelation imaging scheme, there is no need to measure the transmission matrix of the scattering plate and it can be replaced at will.

[0013] 3. The present invention adopts the light field scattering effect of the static scattering medium and the autocorrelation imaging scheme, so the Fourier transform spectrum of the target can be obtained in the near field and far field areas of the object to be measured. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 Schematic diagram of the structure of a far-field super-resolution imaging device based on light field scattering and autocorrelation provided by an embodiment of the present invention.

[0015] Figure 2 It is a Fourier transform spectrum of the object to be measured extracted according to the technical solution provided by the embodiment of the present invention.

[0016] Figure 3 A high-resolution real-space image of the object to be measured reconstructed according to the technical solution provided by the embodiment of the present invention.

[0017] Among them: 1. Laser; 2. Phase modulator; 3. Object to be measured; 4. Scattering plate; 5. Lens; 6. Charge-coupled device CCD (charge-coupled device); 7. Computer. DETAILED DESCRIPTION

[0018] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0019] See attached Figure 1 , which is a schematic diagram of the structure of the far-field super-resolution imaging device based on light field scattering and autocorrelation provided by this embodiment. Figure 1 It can be seen that the far-field super-resolution imaging device based on light field scattering and autocorrelation provided in this embodiment includes a laser 1, a phase modulator 2, an object to be measured 3, a scattering plate 4, a lens 5, a charge-coupled device CCD 6, and a computer 7.

[0020] The light beam emitted by laser 1 is uniformly irradiated on phase modulator 2, which generates a time-varying speckle field that irradiates the object under test 3. The light field information transmitted through the object under test 3 propagates freely for a distance before reaching the scattering plate 4. The scattered light field is imaged by lens 5 onto a charge-coupled device (CCD) 6. The spatial intensity distribution of the scattered light field is recorded by CCD 6 and stored in computer 7. The laser, phase modulator, and CCD are synchronously triggered and controlled by a synchronization signal generator. The planes of the scattering plate, lens, and CCD satisfy an imaging relationship. By correlating the spatial intensity distribution information recorded by the CCD, the Fourier transform spectrum of the object under test is obtained. Phase recovery and reconstruction of this spectrum can then be performed to obtain the real-space image information of the object under test.

[0021] Using the device provided in this embodiment, the imaging method steps are as follows:

[0022] The first step is to obtain the detection signal of the object to be tested

[0023] The laser, phase modulator and CCD are controlled by a synchronous triggering signal generator to work.

[0024] The light beam emitted by the laser 1 is uniformly irradiated on the phase modulator 2, which generates a time-varying speckle field that irradiates the object to be measured 3. The light field information transmitted through the object to be measured 3 propagates freely for a distance and then reaches the scattering plate 4. The scattered light field is imaged by the lens 5 onto the charge-coupled device CCD6. The spatial intensity distribution information of the scattered light field is recorded by the CCD6 and stored in the computer 7.

[0025] In this embodiment, a set of specific experimental parameters is provided: the laser 1 is a semiconductor laser with a wavelength λ of 532 nm, the phase modulator 2 is a rotating frosted glass disk controlled by a computer 7, the laser spot diameter irradiated on the phase modulator 2 is D1 = 2 mm, the object 3 is a three-slit with a slit width of 22.1 μm, a slit height of 111 μm, and a center spacing of 44.2 μm, and the scattering plate 4 is a light-transmitting aperture D P=8mm, single-sided frosted diffuser with 600 grit, lens 5 has a focal length of f = 100mm and a clear aperture of D L =2mm double convex lens, CCD6 is a planar array detector with a target surface size of D4 =2mm; the distance between the phase modulator 2 and the object to be measured 3 is z1 =100mm, the distance between the object to be measured 3 and the scattering plate 4 and the distance between the scattering plate 4 and the lens 5 are both z2 =500mm, the focal length f of the lens 5 is 100mm, the distance between the lens 5 and CCD6 is z3 =125mm, and z2, z3, and f satisfy the Gaussian imaging relationship 1 / z2+1 / z3=1 / f.

[0026] The second step is to extract the Fourier transform spectrum image of the object to be tested

[0027] Assume that CCD6 collects and records a total of S light intensity spatial distribution images, and the corresponding k-th instantaneous light intensity spatial distribution image is recorded as I k (m,n),k=1,2,......,S;where: m and n represent the horizontal and vertical pixel positions of the recorded image respectively. By performing correlation operation on the spatial intensity distribution information recorded by CCD6, the Fourier transform spectrum information of the object to be measured is obtained, that is: Where: M and N represent the total number of horizontal and vertical pixels of the image recorded by CCD6, It represents the Fourier transform spectrum image of the object to be measured.

[0028] In this embodiment, CCD6 collected and recorded S = 2000 instantaneous light intensity images. The total number of horizontal and vertical pixels recorded by CCD5 is M = 289, N = 289, and the pixel size is 6.9 μm. The Fourier transform spectrum of the object to be measured is shown in the attached figure. Figure 2 .

[0029] The third step is to reconstruct the high-resolution image of the object to be measured.

[0030] The Fourier transform spectrum information of the object to be measured is reconstructed through a phase recovery algorithm to obtain its high-resolution real-space image.

[0031] Usually, GS or HIO phase recovery algorithm can be used for image reconstruction. Taking HIO algorithm as an example, first, the amplitude and phase initial estimation of the object to be measured is given. Where f0(m,n) is the initial amplitude distribution, and φ0(m,n) is the initial phase distribution. The amplitude and phase information are updated through iteration. The k-th iteration process is as follows (where k = 1, 2, 3...): (1) Perform Fourier transform on the real-space image reconstructed at the k-1th iteration to obtain its frequency domain image (2) Keep the original phase information unchanged and use the Fourier transform spectrum image of the object to be measured obtained in the second step above replace Right now: (3) Perform inverse Fourier transform on the replaced frequency domain image to obtain the real space image and calculate it according to the set spatial domain constraints to obtain the spatial domain image of the next iteration: Wherein: γ is an adjustable parameter, which is set according to the actual situation. Through multiple iterative operations, a high-resolution real-space image of the object to be measured can be reconstructed.

[0032] See attached Figure 3 , is the high-resolution real-space image of the object to be measured reconstructed in this embodiment. According to the lens diffraction limit calculation formula (1.22λz2 / D L ) The resulting resolution limit is 162.26 μm, and it can only resolve objects with three slits with a slit spacing of 162.26 μm. Using the experimental device provided in this embodiment and the method provided by the present invention, it is possible to fully resolve objects with three slits with a center spacing of 44.1 μm, achieving a super-resolution imaging magnification greater than 3.5 times.

[0033] In the device provided in this embodiment, the diffuser used has a larger aperture than the imaging lens. The diffuser plane, lens, and CCD plane satisfy an imaging relationship, with the image being reduced at the CCD plane. Furthermore, regardless of whether the diffuser is in the near or far field of the object being measured, the Fourier transform spectrum of the target can be obtained through correlation.

[0034] The physical mechanism of the far-field super-resolution imaging of the present invention is described as follows based on the coherence theory of the light field and the physical principle of second-order correlation imaging: According to the coherence theory of the light field, taking the one-dimensional case as an example, the second-order correlation function ΔG (2,2) (η1,η2) is expressed as shown in formula (1): Among them: G (1,1) (ξ1,ξ2) is the first-order cross-correlation function of the light beam emitted by laser 1 after being modulated by phase modulator 2, ξ1 and ξ2 are the coordinates on the plane of phase modulator 2, h1(ξ1,η1) is the impulse response function from the plane of phase modulator 2 to the plane of CCD6, represents the conjugate of the above impulse response function, and η1 and η2 are the coordinates of the CCD6 plane.

[0035] Assuming that the light field generated by the laser beam 1 after random modulation by the phase modulator 2 is uniform and completely incoherent, the first-order cross-correlation function G(1,1) (ξ1,ξ2) is shown in formula (2): G (1,1) (ξ1,ξ2)∝I0δ(ξ1-ξ2) (2) Where I0 is the average distribution of light intensity on the phase plate surface, which is a constant, and δ(x) is the Dirac function.

[0036] Under the condition of satisfying the paraxial approximation, the impulse response number from the phase modulator 2 plane to the CCD 6 plane is shown in formula (3): where x0,x p ,x L are the coordinates of the object surface to be measured, the scattering sheet surface, and the lens surface, respectively. λ is the wavelength of the light wave, and D L is the aperture of the lens; sinc(x)=sin(πx) / πx; P(x p ) is the distribution of the spatial plane where the scattering plate is located; t(x0) is the transmittance function of the object to be measured; z1 is the distance between the phase modulator 2 and the object to be measured 3, the distance between the object to be measured 3 and the scattering plate 4 and the distance between the scattering plate 4 and the lens 5 are both z2, the focal length of the lens 5 is denoted as f, z3 is the distance between the lens 5 and the CCD 6, and z2, z3, and f satisfy the Gaussian imaging relationship 1 / z2+1 / z3=1 / f.

[0037] Substituting equations (2) and (3) into equation (1) and integrating ξ1 and ξ2, we can obtain equation (4):

[0038] If the spot diameter D1 of the light beam emitted by the laser 1 irradiating the phase modulator 2 is large enough, then equation (4) can be simplified to equation (5):

[0039] Convert the above formula (5) into the Fourier transform form as shown in formula (6):

[0040] Represents the Fourier transform. From Equation (6), we can obtain that the Fourier transform spectrum of the object will shift with different values ​​of η2 (i.e., different positions). This means that by changing the value of η2, information of different spatial frequencies of the object's Fourier transform spectrum can be obtained through autocorrelation operation. Taking the one-dimensional case as an example, when η2 takes the value of the center point of the CCD detection surface, the autocorrelation operation can obtain a Fourier transform spectrum of the object with zero frequency at the center of the CCD detection surface and all spatial frequencies symmetrical about the center; when η2 takes the value of the edge point of the CCD detection surface, the autocorrelation operation can obtain a Fourier transform spectrum of the object with zero frequency shifted to the edge of the CCD detection surface, and the higher spatial frequency part of the object's Fourier transform spectrum will appear. Considering that the Fourier transform spectrum of the pure amplitude object to which this device is applicable is symmetrical about the center, when η2 takes the value of the edge of the CCD detection surface, the bandwidth of the object Fourier transform spectrum reconstructed through autocorrelation operation is twice that when η2 takes the value of the center of the CCD detection surface. Based on the above-mentioned Fourier transform map translation principle, by introducing multiple η2 values ​​for autocorrelation calculation instead of the traditional single-point autocorrelation calculation (η2 = 0), we can obtain at most 2k+1 Fourier transform maps of objects with different spatial frequency distributions (k = (D4 / Δη2-1) / 2, D4 is the lateral size of the CCD detection surface, Δη2 is the pixel size of the CCD detection surface, and the size of a single Fourier transform map is 1×(2k+1) pixels). Then, the obtained 2k+1 Fourier transform maps of the object are translated and superimposed according to the corresponding spatial frequency distribution. The size of the superimposed object Fourier transform map is expanded from the original 1×(2k+1) pixels to 1×(4k+1) pixels. At the same time, the Fourier transform map bandwidth of the object is expanded to twice the original size, which will be beneficial to super-resolution imaging. The above process can be simplified to the following equation (7):

[0041] Below, based on the attached Figure 1 The optical system structure will be theoretically deduced and analyzed to verify the effectiveness of the present invention by analyzing the influence of the presence or absence of a scattering plate on the super-resolution imaging performance.

[0042] (1) Imaging performance without scattering sheet

[0043] When no scattering sheet is placed, there is only one clear aperture D at the plane at distance z2 from the object to be measured. p Limit, then P(x p ) can be expressed as: Formula (7) can be simplified as shown in formula (8): in: The result of formula (8) shows that the Fourier transform spectrum of the object is firstly pThe lens is then imaged onto a CCD by a coherent imaging system, and the Fourier transform maps of the object corresponding to different positions nΔη are aligned and superimposed according to the position of zero frequency. L When it is large enough, the quadratic phase factor can be expressed as At this time, the aperture D p The Fourier transform of the object after filtering can be perfectly detected. However, when the lens aperture D L Relatively small, due to The existence of the factor, the Fourier transform spectrum information of the object with higher spatial frequencies is lost due to the vignetting effect, which shows that as the lens aperture D L As the spatial resolution of the system decreases, the spatial resolution of the system will degrade.

[0044] (2) Imaging performance with scattering sheet

[0045] Place a light source with a clear aperture of D on a plane at a distance z2 from the object to be measured. p When the random scattering sheet is: P(x p )=A(x p )×exp{jφ(x p )}, Compared with the case without diffuser, P(x p ) has an extra φ(x p ), which is caused by the optical path difference caused by the random height fluctuation of the scattering plate. In this case, Equation (7) can be simplified to Equation (9): Here, <·> represents the concept of ensemble average. Combined with the statistical characteristics of the scattering sheet, we can obtain formula (10):

[0046] In the above formula, σ 2 is φ(x p ) is related to the variance of the height fluctuation of the scattering plate surface. related Represents the roughness of the scattering sheet surface; l c is the phase φ(x p ) is related to the autocorrelation function of the optical parameter, which is called the "coherence length". At this time, substitute equation (10) into equation (9), and in l c When you're small enough, We can get formula (11):

[0047] Comparing the results of equations (8) and (11), it can be clearly seen that when there is a scattering plate, the quadratic phase factor and This is due to the statistical characteristics of the scattering film. Therefore, the vignetting effect caused by the above-mentioned quadratic phase factor will also be removed, and the higher spatial frequency information of the object's Fourier transform spectrum can still be obtained, even at the lens aperture D L Under the condition that the minimum resolution detail of the target is only slightly larger than that of the target. Further, for the more general case: when the CCD is usually located at the position of the scattering plate, the spatial resolution of the system depends on the lateral size of the CCD detection surface and the distance between the object and the CCD. However, according to formula (11), under this imaging device, the spatial resolution of the system depends on the light aperture D of the scattering plate. P , and in practice it is easy and inexpensive to manufacture large-diameter diffusers. In addition, whether the diffuser is located in the far field or the Fresnel region of the object, Equation (11) is valid. Finally, according to Equation (6), it should be emphasized that when the diffuser is placed in the system, by calculating ΔG (2,2) Each Fourier transform spectrum of an object reconstructed by (η1, η2 = nΔη) has a speckle effect. However, this speckle effect can be calculated by ΔG in formula (11): (2,2) (η1) is removed, and the bandwidth of the Fourier transform spectrum of the object will be expanded to twice the original one, which means that the spatial resolution of the system will be doubled compared with the spatial resolution calculated by formula (6). Figure 1 In the device shown, when a scattering plate is used to further modulate the transmission information of the target, the proposed method can break through the limitation of the lateral size of the CCD detection surface on the resolution of autocorrelation imaging, even when the scattering plate is imaged onto the detector through a traditional imaging system with a small transmission aperture.

[0048] In order to ensure that the correct Fourier transform spectrum information of the object to be measured can be obtained, the correlation length l of the scattering plate is required to be c is smaller than the spectral resolution of the object to be measured on the plane where the scattering plate is located, and the spatial resolution of the imaging system corresponding to the rear lens 5 at the scattering plate (λz2 / D L ) must also be less than 1 / 2 of the spectrum resolution of the object to be measured in the plane where the scattering plate is located.

[0049] In summary, it can be seen that the spatial resolution of the system imaging can be controlled by adjusting the aperture of the scattering plate. The spatial resolution of the entire system is no longer limited by the aperture of the receiving system lens. This proves that the proposed imaging device and method based on light field scattering and autocorrelation have the ability of far-field super-resolution imaging.

Claims

1. A far-field super-resolution imaging device based on light field scattering and autocorrelation, characterized by: The invention comprises a laser (1), a phase modulator (2), a scattering plate (4), a lens (5), a charge coupled device (CCD) (6) and a computer (7). The laser (1), the phase modulator (2) and the charge coupled device (CCD) (6) are synchronously triggered and controlled by a synchronous signal generator to operate. The light beam emitted by the laser (1) irradiates the phase modulator (2), and the phase modulator (2) generates a time-varying speckle field that irradiates the object to be measured (3). The light intensity information transmitted by the object to be measured (3) is freely transmitted to the scattering plate (4). The light field information scattered by the scattering plate (4) is imaged on the charge coupled device (CCD) (6) through the lens (5). The spatial intensity distribution information of the scattered light field is recorded by the CCD (6) and stored in the computer (7). A high-resolution real-space image of the object to be measured is obtained through correlation operation and image reconstruction processing.

2. The far-field super-resolution imaging device based on light field scattering and autocorrelation according to claim 1, characterized in that: The scattering plate (4) plane, the lens (5) and the charge coupled device (CCD) plane form a single-lens imaging system, the magnification of which is 1 / M, where M>1; the spatial resolution of the imaging system at the scattering plate is less than 1 / 2 of the spectrum resolution of the object to be measured at the scattering plate plane.

3. The far-field super-resolution imaging device based on light field scattering and autocorrelation according to claim 1, characterized in that: The correlation length l of the scattering plate c Smaller than the spectral resolution of the object to be measured in the scattering plane.

4. The far-field super-resolution imaging device based on light field scattering and autocorrelation according to claim 1, characterized in that: The light-clearing aperture of the scattering plate meets the constraint conditions: the light-clearing aperture is larger than the light-clearing aperture of the lens, the maximum light-clearing aperture is less than M times the CCD detection aperture, M is the inverse of the magnification of the imaging system, and the minimum light-clearing aperture is larger than the CCD detection aperture, so as to achieve far-field super-resolution imaging, and the magnification of super-resolution imaging is proportional to the light-clearing aperture of the scattering plate.

5. A far-field super-resolution imaging method based on light field scattering and autocorrelation, characterized in that The following steps are involved: (1) Acquisition of detection signals of the object to be measured The laser, phase modulator, and charge-coupled device (CCD) are triggered and controlled by a synchronous signal generator. The laser beam irradiates the phase modulator, which generates a time-varying speckle field that irradiates the object to be measured. After the light intensity information transmitted by the object to be measured freely propagates to the scattering plate, the light field information scattered by the scattering plate is imaged on the charge-coupled device (CCD) through a lens. The spatial intensity distribution information of the scattered light field recorded by the CCD is stored in a computer. (2) Extraction of Fourier transform spectrum image of the object to be tested The charge coupled device CCD collects and records a total of S instantaneous light intensity spatial distribution images, and the corresponding kth instantaneous light intensity spatial distribution image is recorded as I k (m,n),k=1,2,......,S; where: m and n represent the horizontal and vertical pixel positions of the recorded image respectively; according to formula (1), the spatial intensity distribution information recorded by the charge coupled device CCD is correlated to obtain the Fourier transform spectrum image of the object to be measured information: Where: M and N are the total number of horizontal and vertical pixels of the image recorded by the charge coupled device CCD; (3) High-resolution image reconstruction of the object to be measured The Fourier transform spectrum image of the object to be measured is obtained by using the phase recovery algorithm Reconstruction is performed to obtain a high-resolution real-space image of the object to be measured.

Images