Equivalent confocal pinhole imaging method, system and medium

Abstract

The invention provides an equivalent confocal pinhole imaging method, which comprises the following steps of: arranging a light splitting module in a confocal imaging system, splitting detection light emitted by an object point through the light splitting module, dividing the detection light into at least two beams, and dividing the at least two beams of detection light into at least two different imaging channels to be imaged on an image surface; the detection light emitted by the object point generates a single independent image point on an image plane through a single imaging channel, at least two image points are overlapped on the image plane, and after interference occurs at the overlapped image point positions, the detection light is received by a detector; the at least two detection light beams interfere with each other to cause change of the intensity of an image point to form an interference influence effect, a distribution function of the interference influence effect is w (x, y), and the distribution function of the interference influence effect is kept fixed relative to a pinhole transmittance distribution function h (x, y) in a confocal scanning process; and the distribution of the probe light after penetrating through the pinhole is modulated through an equivalent confocal pinhole transmittance distribution function w (x, y) * h (x, y).

Description

Technical Field

[0001] The present invention belongs to the technical field of microscopic imaging, and particularly relates to an equivalent confocal pinhole imaging method, system, device and readable storage medium. Background Art

[0002] In the prior art, confocal imaging systems can generally be divided into the following two categories:

[0003] The first type of confocal imaging system uses a single-pixel detector with a single pixel such as a PMT to receive, or even if a multi-pixel detector is used for reception, the individual pixels of the multi-pixel detector are combined into an equivalent single pixel for use. The detector receives the detected signal light after passing through the pinhole. This detected signal light changes with time during the confocal scanning process. By reconstructing this signal that changes with time, confocal image information can be obtained. Generally, a laser scanning confocal microscope (LSCM) belongs to this category.

[0004] As Figure 2 shown, the illumination light emitted by the optical system illuminates the object surface, causing the object points on the object surface to emit detected light. The detected light passes through the optical system and is imaged on the image surface, and is received by a single-pixel photodetector (such as a PMT, APD, etc.) after passing through the pinhole provided on the image surface. Without loss of generality, the part including the optical system, illumination light, and pinhole performs a scanning motion relative to the object surface. The detector can move relative to the object surface or remain stationary relative to the object surface, as long as it can receive the light signal passing through the pinhole. Usually, the confocal scanning using a galvanometer can actually be equivalent to the above scanning motion. During the scanning process, the intensity of the detected light signal received by the detector changes with time. By reconstructing this signal that changes with time, confocal image information can be obtained.

[0005] Let the illumination point spread function be PSF ex (x, y, z). The illumination point spread function refers to the point spread function caused by the illumination light, not only the distribution function of the illumination light itself, but also the distribution function of the scattered light generated by the illumination of the illumination light, or the distribution function of the fluorescence excited by the illumination light, or the distribution function of the second or multiple harmonics caused by the illumination light, or the distribution of superoscillatory light spots caused by the illumination light, etc. Also, the illumination point spread function PSF ex (x, y, z) can be any distribution form of a function obtained by physically modulating the illumination light distribution, not only the distribution form of an Airy spot or a Gaussian spot, but also the distribution form of an array of spots, or the distribution form of a Bessel spot, or the distribution form of a superoscillatory light spot, etc. Let the point spread function of the detected light be PSF em(x, y, z), and similarly, it can be any distribution form of a function obtained by physically modulating the detection light distribution, not only referring to the distribution forms of Airy spots or Gaussian spots, but also the distribution form of an array of spots, or even the distribution form of Bessel spots, etc. Let the pinhole function be h(x, y), and similarly, h(x, y) not only refers to the distribution function of a single pinhole, but also the distribution function of an array of pinholes, and even more broadly, it can be any physically realizable transmittance distribution function.

[0006] The point spread function PSF of the entire confocal system above sys (x, y, z) can be expressed as the following formula (1):

[0007] PSF sys (x, y, z) = PSF ex (x, y, z) × [PSF em (x, y, z) * h(x, y)] Formula (1)

[0008] Where, * represents convolution, and × represents multiplication. When h(x, y) is not in the form of an infinitesimal Dirichlet function, due to the convolution broadening effect of h(x, y) on PSF em (x, y, z), it will broaden PSF em (x, y, z), resulting in the broadening of the final PSF sys (x, y, z), and reducing the imaging resolution of the system. When the pinhole is a single pinhole and the pinhole diameter approaches infinity, h(x, y) approaches the Dirichlet function, and at this time

[0009] PSF sys (x, y, z) = PSF ex (x, y, z) × PSF em (x, y, z)

[0010] If PSF ex (x, y, z) and PSF em (x, y, z) are both in the form of diffraction-limited Airy spots and are equal, then PSF sys (x, y, z) = [PSF em (x, y, z)] 2 . At this time, the resolution of the confocal system is times. However, at this time, the pinhole tends to be infinitesimal, and no light can pass through the optical system, so it cannot be actually realized. The method of improving the imaging resolution of the confocal system by reducing the pinhole size will lead to a sharp decrease in the effectively utilized light flux, which is an inherent defect of the existing technology. Usually, the pinhole diameter is taken as 1 AU, that is, the diameter of an Airy disk of 1 diffraction limit. At this time, most of the light emitted by the object point can pass through the pinhole. However, due to the convolution broadening effect of the pinhole h(x,y) on the detection point spread function PSF em (x,y,z), the resolution of the confocal system will be reduced to a level close to that of wide-field imaging, and the effect of improving the imaging resolution is lost.

[0011] The second type of confocal imaging system uses a multi-pixel detector with multiple pixels such as a camera to receive. The detector receives the detected signal light passing through the pinhole. This signal light has different distributions in space. During the confocal scanning process, the pixels at different spatial positions on the multi-pixel detector collect the signal light, thereby obtaining image information. For example, the spinning disk confocal imaging system using a camera to receive belongs to this type.

[0012] As Figure 3 shown, the illumination light emitted by the optical system illuminates the object surface, causing the object points on the object surface to emit detection light. The detection light passes through the optical system and is imaged on the image surface, and is received by a multi-pixel photodetector (such as a camera, an array PMT, etc.) after passing through the pinhole set on the image surface. Without loss of generality, the part including the optical system, the illumination light, and the pinhole performs a scanning motion relative to the object surface. The detector can move relative to the object surface or remain stationary relative to the object surface, as long as it can receive the light signal passing through the pinhole. Usually, the confocal scanning using a galvanometer can be essentially equivalent to the above scanning motion. The pixels at multiple different spatial positions on the detector receive the signal light at different spatial positions, and process the received signals to obtain confocal image information.

[0013] Let the illumination point spread function be PSF ex (x,y,z). The illumination point spread function refers to the point spread function caused by the illumination light, not only the distribution function of the illumination light itself, but also the distribution function of the scattered light generated by the illumination of the illumination light, or the distribution function of the fluorescence excited by the illumination light, or the distribution function of the second or multiple harmonics caused by the illumination light, or the superoscillatory spot distribution caused by the illumination light, etc. Also, the illumination point spread function PSF ex (x,y,z) can be any distribution form of a function obtained by physically modulating the illumination light distribution, not only the distribution form of an Airy spot or a Gaussian spot, but also the distribution form of an array of spots, or the distribution form of a Bessel spot, or the superoscillatory spot distribution form, etc. Let the point spread function of the detection light be PSF em(x, y, z), similarly, it can be any distribution form of a function obtained by physically modulating the detection light distribution, not only referring to the distribution forms of Airy spots or Gaussian spots, but also the distribution form of array spots, or even the distribution form of Bessel spots, etc. Let the pinhole function be h(x, y), and similarly, h(x, y) not only refers to the distribution function of a single pinhole, but also the distribution function of an array of pinholes, or even more generally, any physically realizable transmittance distribution function.

[0014] The point spread function PSF of the entire confocal system above sys (x, y, z) can be expressed as the following formula (2):

[0015] PSF sys (x, y, z) = [PSF ex (x, y, z) * h(x, y)] × PSF em (x, y, z) Formula (2)

[0016] Among them, * represents convolution, and × represents multiplication. When h(x, y) is not in the form of an infinitesimal Dirichlet function, due to the convolution broadening effect of h(x, y) on PSF ex (x, y, z), it will broaden PSF ex (x, y, z), resulting in the broadening of the final PSF sys (x, y, z), and reducing the imaging resolution of the system. When the pinhole is a single pinhole and the pinhole diameter tends to be infinitesimal, h(x, y) tends to the Dirichlet function, and at this time

[0017] PSF sys (x, y, z) = PSF ex (x, y, z) × PSF em (x, y, z)

[0018] If PSF ex (x, y, z) and PSF em (x, y, z) are both in the form of diffraction-limited Airy spots and are equal, then PSF sys (x, y, z) = [PSF em (x, y, z)] 2 . At this time, the resolution of the confocal system is times. However, at this time, the pinhole tends to be infinitesimal, and no light can pass through the optical system, so it cannot be actually realized. By reducing the pinhole size to improve the imaging resolution of the confocal system, the light flux that can be effectively utilized will decrease sharply, which is an inherent defect of the existing technology. Usually, the pinhole diameter is taken as 1 AU, that is, the diameter of an Airy disk of 1 diffraction limit. At this time, most of the light emitted by the object point can pass through the pinhole. However, due to the convolution broadening effect of the pinhole h(x,y) on the illumination spot spread function PSF ex (x,y,z), the resolution of the confocal system will be reduced to a level close to that of wide-field imaging, and the effect of improving the imaging resolution is lost.

[0019] In the prior art, a technique called pixel reassignment or photon reassignment is used to achieve the purpose of improving the light flux and resolution of the confocal imaging system. The Airyscan technology of Zeiss, the spinning disk confocal super-resolution technology of Olympus, ISM, rescan confocal microscopy imaging technology, MSIM, iSIM, and various other multi-focus confocal super-resolution technologies all belong to this category. A common limitation of such technologies is that they all require the use of multi-pixel detectors and cannot use single-pixel detectors. Moreover, the system structures of these technologies are complex and costly, which is not conducive to popularization and application. ISM and MSIM require complex algorithm reconstruction after multiple frames of images are taken to obtain super-resolution images, and the imaging speed is slow. In such technologies, technologies that use multi-focus simultaneous parallel scanning, such as the spinning disk confocal super-resolution technology of Olympus, rescan confocal microscopy imaging technology, MSIM, iSIM, etc., often require the multiple foci of the illumination light to have sparsity, that is, the distance between the foci is required to be greater than a certain distance, such as 10 AU, to achieve good results. For the case where the foci of the illumination light are very dense, such as using lattice-structured light generated by interference as the illumination light, the distance between the foci of the illumination light can be equal to or even less than 1 AU, and the above methods are difficult to apply and difficult to produce the effect of improving the light utilization efficiency or the imaging resolution.

[0020] In summary, due to the mutual restriction of the pinhole size on the light utilization efficiency and resolution in confocal imaging technology. In traditional systems, reducing the pinhole can improve the resolution, but it causes a large amount of signal light loss; while increasing the pinhole improves the light efficiency at the cost of sacrificing the resolution. Summary of the Invention

[0021] The purpose of the present invention is to solve the problems in the prior art, and a method, system and medium for equivalent confocal pinhole imaging are proposed. By introducing a beam splitting module and an interference effect, the contradiction between the light utilization efficiency and the imaging resolution in the confocal imaging system is solved, the simultaneous improvement of high resolution and high light efficiency is realized, and excellent system compatibility and scalability are also achieved.

[0022] To achieve the above object, the present invention adopts the following technical solutions.

[0023] The equivalent confocal pinhole imaging method includes the following steps:

[0024] A beam splitting module is set in the confocal imaging system, and the detection light emitted by the object point is split by the beam splitting module, and the detection light is split into at least two beams, and at least two beams of detection light are imaged onto the image plane through at least two different imaging channels;

[0025] The detection light emitted by the object point generates a single independent image point on the image plane through a single imaging channel, at least two image points coincide in position on the image plane, interference occurs at the position of the coincident image points, and is received by the detector after passing through the pinhole on the image plane;

[0026] At least two beams of detection light interfere to cause a change in the intensity of the image point to form an interference influence effect, and the distribution function of the interference influence effect is w(x, y), and the interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process;

[0027] The distribution of the detection light passing through the pinhole is modulated by the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y).

[0028] Further, the modulation of the distribution of the detection light passing through the pinhole by the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y) includes:

[0029] Set the interference influence effect distribution function w(x, y) and the pinhole transmittance distribution function h(x, y), so that the part where the value of the interference influence effect distribution function w(x, y) is the largest or close to the largest coincides with the part where the value of the pinhole transmittance distribution function h(x, y) is the largest or close to the largest.

[0030] Further, determine the optical path difference between the imaging channels, the relative intensity distribution of the imaging channels, and the spatial position distribution of the imaging channels according to the setting of the beam splitting module, and determine the interference influence effect distribution function w(x, y) according to the optical path difference between the imaging channels, the relative intensity distribution of the imaging channels, and the spatial position distribution of the imaging channels.

[0031] Further, phase delay is performed on the single imaging channel, and the phase difference between each detection beam is adjusted to adjust the interference influence effect distribution function w(x, y).

[0032] Further, the way for the detector to generate a confocal image includes that the intensity of the detection light signal received by the detector changes with time, and the confocal image information is obtained by reconstructing the signal that changes with time.

[0033] Furthermore, it further includes that pixels at at least two different spatial positions on the detector receive signal lights at different spatial positions, process the received signals, and obtain confocal image information.

[0034] To achieve the above object, the present invention further provides an equivalent confocal pinhole imaging system, which applies an equivalent confocal pinhole imaging method as described above, and includes an optical system, a beam splitting module, and a detector sequentially arranged along the optical path, wherein,

[0035] The illumination light emitted by the optical system illuminates the object surface, and the object points on the object surface emit detection light, and the detection light passes through the optical system;

[0036] The beam splitting module splits the detection light emitted by the object point and passing through the optical system into at least two beams, and the at least two beams of detection light are imaged onto the image surface through at least two different imaging channels. A single imaging channel generates a single independent image point on the image surface, and at least two image points coincide in position on the image surface, interfere at the coincident image point positions, and are received by the detector after passing through the pinhole on the image surface;

[0037] The interference of at least two detection light beams causes the intensity change of the image point to form an interference influence effect. The distribution function of the interference influence effect is w(x, y). The interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process. By setting the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y) to modulate the distribution of the detection light after passing through the pinhole, the part where the value of the interference influence effect distribution function w(x, y) is the largest or close to the largest coincides with the part where the value of the pinhole transmittance distribution function h(x, y) is the largest or close to the largest.

[0038] Furthermore, it further includes a phase delay unit, which is arranged on the optical path between the beam splitting module and the detector and is used to adjust the phase difference between each detection light beam to adjust the interference influence effect distribution function w(x, y).

[0039] To achieve the above object, the present invention further provides an electronic device, including a memory and a processor. The memory stores a program running on the processor, and when the processor runs the program, it executes the steps of the equivalent confocal pinhole imaging method as described above.

[0040] To achieve the above object, the present invention further provides a computer-readable storage medium, on which computer instructions are stored. When the computer instructions run, they execute the steps of the equivalent confocal pinhole imaging method as described above.

[0041] The present invention provides an equivalent confocal pinhole imaging method, system and medium, which have the following beneficial effects:

[0042] 1. Break through the traditional pinhole limitation and achieve double optimization of resolution and optical efficiency: The detection light emitted from the object point is divided into multiple beams (such as two beams or more) by a beam splitting module, and it is ensured that the split beams coincide and interfere at the same position on the image plane. The intensity modulation (such as the w(x,y) function) generated by the interference effect and the pinhole transmittance function (such as the h(x,y) function) act together to form an equivalent pinhole function. This equivalent function has both small size (such as a full width at half maximum of 0.25 AU or smaller) and high transmittance characteristics: its narrow distribution significantly suppresses the convolution broadening of the pinhole on the point spread function (PSF), increasing the resolution by 1.4 times or more; while the coherent superposition of multiple beams makes the optical efficiency close to or even reach the level of a traditional large pinhole (1 AU), breaking the traditional trade-off relationship between optical efficiency and resolution at the physical level.

[0043] 2. The present invention includes multiple beam splitting implementation paths, and the beam splitting module is flexibly designed to adapt to various imaging systems, including but not limited to: beam splitting element solutions (such as beam splitting plates, polarization beam splitting cubes): The beam splitting optical path is adjusted by a mirror to achieve multi-beam interference, which is suitable for the transformation of traditional confocal systems; diffraction element solutions (such as checkerboard gratings, metasurfaces): The split beams are generated by grating diffraction and aperture filtering, supporting a compact optical path design. Multiple solutions can expand the number of split beams (such as multi-stage beam splitting in the X / Y directions) and integrate phase delay plates to accurately control the optical path difference and interference phase, adapting to various system configurations such as single / multi-pixel detectors, single focus / multi-focus illumination, single pinhole / array pinholes, etc., with extremely high flexibility.

[0044] 3. The full-field resolution is significantly improved, supporting high-throughput imaging: In a linear structured light illumination multi-focus system (such as Example 4), by combining periodic illumination foci (such as spaced λ / 2NA) and an array of pinholes, through checkerboard grating beam splitting and multi-channel interference, the high-frequency modulation characteristics of the equivalent pinhole function improve the full-field resolution to 2 times the wide-field level, and support parallel scanning and fast imaging. Similarly, in a nonlinear structured light illumination multi-focus system, the full-field resolution can be improved to more than 2 times the wide-field level, and support parallel scanning and fast imaging. This feature provides an efficient tool for scenarios such as dynamic observation of living samples and high-throughput biological detection.

[0045] 4. Mathematical verification and experimental repeatability: The technical solution is verified through strict formula derivations (such as Formulas 3 and 4) and simulations, clarifying the modulation mechanism of the equivalent pinhole function on the PSF to ensure the predictability of the design. Experimental data show that the improvement of system resolution and the optimization of optical efficiency are highly repeatable, and there is a clear quantitative relationship between parameter adjustments (such as pinhole size, grating period) and performance indicators (such as interference period λ / 2NA), laying a theoretical foundation for engineering applications.

[0046] Other features and advantages of the present invention will be set forth in the following description, and in part will be obvious from the description, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] The drawings are provided to further understand the present invention, and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention, and do not constitute a limitation to the present invention. In the drawings:

[0048] Figure 1 is a flowchart of an equivalent confocal pinhole imaging method of the present invention;

[0049] Figure 2 is a schematic diagram of the principle of a confocal imaging system using a single-pixel detector in the prior art;

[0050] Figure 3 is a schematic diagram of the principle of a confocal imaging system using a multi-pixel detector in the prior art;

[0051] Figure 4 is a schematic diagram of an equivalent confocal pinhole imaging system of the present invention;

[0052] Figure 5 is a schematic diagram of a beam splitting module using a beam splitting optical element of the present invention;

[0053] Figure 6 is a schematic diagram of a beam splitting module using a diffractive optical element of the present invention;

[0054] Figure 7 is a schematic diagram of an embodiment of a confocal imaging system of the present invention;

[0055] Figure 8 is a schematic diagram of another embodiment of a confocal imaging system of the present invention;

[0056] Figure 9 is a schematic diagram of yet another embodiment of a confocal imaging system of the present invention;

[0057] Figure 10 is a schematic diagram of the structure of an electronic device 300 for implementing the embodiments of the present application.

[0058] Wherein:

[0059] 1 - optical system, 2 - beam splitting module, 3 - detector,

[0060] 4 - object plane, 5 - object point, 6 - image plane,

[0061] 7 - image point, 8 - pinhole, 9 - beam splitting plate,

[0062] 10 - Mirror, 11 - Objective lens, 12 - Phase retarder,

[0063] 13 - Tube lens, 14 - First relay mirror, 15 - Second relay mirror,

[0064] 16 - Diaphragm, 17 - Relay image plane, 18 - Pinhole array. Detailed implementation mode

[0065] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not used to limit the present invention.

[0066] All dimensions involved in the embodiments of the present invention are normalized to the object space for discussion.

[0067] Embodiment 1

[0068] Figure 1 For the flowchart of the equivalent confocal pinhole imaging method according to the present invention, reference will be made below to Figure 1 to describe the equivalent confocal pinhole imaging method of the present invention in detail.

[0069] In step 101, a beam splitting module is set in the confocal imaging system, and the detection light emitted from the object point is split by the beam splitting module into at least two beams, and the at least two beams of detection light are imaged onto the image plane through at least two different imaging channels.

[0070] In step 102, the detection light emitted from the object point generates a single independent image point on the image plane through a single imaging channel, at least two image points coincide in position on the image plane, and after interference occurs at the coincident image point position, it is received by the detector.

[0071] In this embodiment, multiple beams of detection light are imaged at the same image point position on the image plane. That is to say, the detection light emitted from any object point on the object plane is split into multiple different imaging channels and imaged onto the image plane through an optical system with a beam splitting module. Each imaging channel generates an independent image point on the image plane, and these multiple image points coincide in position on the image plane.

[0072] In this embodiment, for the part where coherent enhancement occurs, the light is more concentrated. If the corresponding pinhole function has a higher transmittance in this part, the light can effectively pass through. It can achieve the purpose of improving the light transmittance or light utilization efficiency compared with the case where this equivalent pinhole is not used. Or, for the same light utilization efficiency, a smaller pinhole can be used. For a smaller pinhole, the convolution broadening effect is smaller. The purpose is to reduce or eliminate the convolution broadening effect of the pinhole on the point spread function.

[0073] In step 103, at least two detection light beams interfere with each other, resulting in a change in the intensity of the image point to form an interference influence effect. The distribution function of the interference influence effect is w(x, y), and the interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process.

[0074] Optionally, assuming that the coherence length of the detection light is long enough, or the optical path differences of all channels are short enough, the detection lights of these multiple channels, because they are emitted from the same object point, will interfere with each other after overlapping at the image point, resulting in a change in the intensity of the image point. The principle of this interference effect is similar to that of a Mach-Zehnder interferometer. This effect of the change in the intensity of the image point due to the interference effect will change with the different positions of the image point. This is because when the position of the image point is different, the optical path differences between the respective imaging channels will change, resulting in a change in the interference effect. The effect of the intensity of the image point changing with position due to the interference of multiple detection light beams can be called the interference influence effect, and its distribution function can be expressed as w(x, y).

[0075] In step 104, the distribution of the detection light passing through the pinhole is modulated by the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y).

[0076] Optionally, as can be seen from the above steps, the distribution of w(x, y) is determined by the optical path differences between the respective imaging channels and depends on the settings of the beam splitting module in the optical system. During the confocal scanning process, the optical system is fixed relative to the position of the pinhole. Therefore, the interference influence effect distribution function w(x, y) also remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process. Both w(x, y) and h(x, y) modulate the distribution of the detection light passing through the pinhole, and their product w(x, y)×h(x, y) is the total modulation effect of the two. Therefore, w(x, y)×h(x, y) can be regarded as the equivalent confocal pinhole transmittance distribution function.

[0077] Optionally, the way for the detector to generate a confocal image includes that the confocal imaging system scans relative to the object surface, the intensity of the detection light signal received by the detector changes with time, and the confocal image information is obtained by reconstructing the signal that changes with time.

[0078] Optionally, it further includes that the confocal imaging system scans relative to the object surface, pixels at at least two different spatial positions on the detector receive signal lights at different spatial positions, and the received signals are processed to obtain the confocal image information.

[0079] In this embodiment, when the interference influence effect distribution function w(x,y) and the pinhole transmittance distribution function h(x,y) are normalized, they are both functions with numerical ranges between 0 and 1. The interference influence effect distribution function w(x,y) and the pinhole transmittance distribution function h(x,y) are set such that some parts of the interference influence effect distribution function w(x,y) with larger numerical values closer to 1 coincide with some parts of the pinhole transmittance distribution function h(x,y) with larger numerical values closer to 1. In this way, the equivalent confocal pinhole transmittance distribution function w(x,y)×h(x,y) can ensure that some parts of the numerical values are close to 1, and light energy can effectively pass through these parts of the equivalent confocal pinhole function that are close to 1. The light with enhanced coherence can efficiently pass through these parts of the equivalent confocal pinhole that are close to or reach 1. Compared with the case without the interference influence effect, the light will not be concentrated in the coherently enhanced part due to coherent enhancement. That is, even if the pinhole transmittance distribution function h(x,y) with the same distribution is used, the final light transmittance will be inferior to the effect of the equivalent confocal pinhole. The essence of the setting method is to make the coherently enhanced part of the interference influence effect distribution function w(x,y) be located in the part with high transmittance of the pinhole transmittance distribution function h(x,y), and use the coherent effect to cause the redistribution of light, so that the light energy converges to the coherently enhanced part, that is, the part with high pinhole transmittance. Therefore, the light can pass through the pinhole more efficiently.

[0080] Optionally, after the interference influence effect distribution function w(x,y) is normalized, a value greater than 0.5 can be used as an indication that the light has the effect of coherent enhancement.

[0081] In this embodiment, due to the interference effect, the light energy is transferred from the coherently weakened part to the coherently enhanced part, and then passes through the corresponding part of the pinhole, thereby improving the utilization efficiency of the light.

[0082] In this embodiment, after the pinhole transmittance distribution function h(x,y) is set, the corresponding interference influence effect distribution function w(x,y) is set such that the coherently enhanced part of the interference influence effect distribution function w(x,y) is located in the part with high transmittance of the pinhole transmittance distribution function h(x,y), thereby transferring the light energy from the part with low pinhole transmittance to the part with high pinhole transmittance, and realizing the improvement of the total light transmittance.

[0083] Optionally, the beam splitting module in the step of "splitting the detection light emitted by the object point by the beam splitting module, splitting the detection light into at least two beams, and imaging at least two beams of detection light into at least two different imaging channels on the image plane" has multiple implementation manners. Multiple beam splitting modules located in the confocal imaging system can all achieve the splitting and interference of the detection light, redistribute the light energy spatially, transfer it from the part with low pinhole transmittance to the part with high pinhole transmittance, and achieve an increase in the total light transmittance. The preferred embodiments described in the present invention are only used to illustrate and explain the present invention, and are not used to limit the present invention. The beam splitting module described in the present invention includes but is not limited to the beam splitting modules listed in this embodiment.

[0084] Embodiment 2

[0085] Figure 4 FIG. is a schematic diagram of an equivalent confocal pinhole imaging system according to the present invention, as Figure 4 shown, an equivalent confocal pinhole imaging system of the present invention includes an optical system 1, a beam splitting module 2, and a detector 3 arranged in sequence along the optical path. Among them,

[0086] The illumination light emitted by the optical system 1 illuminates the object plane 4, and the object point 5 on the object plane 4 emits detection light, and the detection light passes through the optical system 1;

[0087] The beam splitting module 2 splits the detection light emitted by the object point 5 and passing through the optical system 1, splits the detection light into at least two beams, and at least two beams of detection light are imaged into at least two different imaging channels on the image plane 6. A single imaging channel generates a single independent image point 7 on the image plane 6. At least two image points 7 coincide in position on the image plane 6, interference occurs at the position of the coincident image points 7, and is received by the detector 3 after passing through the pinhole 8 on the image plane 6;

[0088] The intensity change of the image point 7 caused by the interference of at least two detection light beams forms an interference influence effect. The distribution function of the interference influence effect is w(x, y). The interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process. By setting the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y) to modulate the distribution of the detection light passing through the pinhole 8, the part where w(x, y) has enhanced coherence is located at the position with the highest transmittance of h(x, y).

[0089] It further includes a phase delay unit, and the phase delay unit is arranged on the optical path between the beam splitting module 2 and the detector 3, and is used to adjust the phase of the detection light to adjust the interference influence effect distribution function w(x, y).

[0090] As an example, for the first type of confocal imaging system described in the background art, under the action of the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y), the point spread function PSF of the system sys (x, y, z) can be expressed by the following formula (3):

[0091] PSF sys (x, y, z) = PSF ex (x, y, z) × {PSF em (x, y, z) * [w(x, y) × h(x, y)]} (3)

[0092] where, * represents convolution, and × represents multiplication. PSF ex (x, y, z) is the illumination point spread function, and PSF em (x, y, z) is the detection point spread function, and x, y, z are spatial coordinate axes, where x, y are spatial coordinate axes perpendicular to the optical axis, and z is the spatial coordinate axis parallel to the optical axis.

[0093] For the second type of confocal imaging system described in the background art, under the action of the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y), the point spread function PSF sys (x, y, z) can be expressed by the following formula (4):

[0094] PSF sys (x, y, z) = {PSF ex (x, y, z) * [w(x, y) × h(x, y)]} × PSF em (x, y, z) (4)

[0095] where, * represents convolution, and × represents multiplication. PSF ex (x, y, z) is the illumination point spread function, and PSF em (x, y, z) is the detection point spread function, and x, y, z are spatial coordinate axes, where x, y are spatial coordinate axes perpendicular to the optical axis, and z is the spatial coordinate axis parallel to the optical axis.

[0096] It can be seen from formula (3) and formula (4) that w(x, y)×h(x, y) completely replaces h(x, y) for PSF em (x, y, z) or PSF ex(x, y, z) for convolution broadening. If appropriate w(x, y) and h(x, y) can be selected such that w(x, y) × h(x, y) has a high light transmission efficiency while also having a small size, then it is possible to improve the resolution of the confocal imaging system while having a high light utilization efficiency, thereby alleviating or eliminating the above-mentioned limitation of the mutual restriction between the light utilization efficiency and the imaging resolution. For example, by appropriately setting w(x, y) and h(x, y) such that the coherently enhanced part of w(x, y) is located at the position with a high transmittance of h(x, y), the light utilization efficiency can be effectively improved or the size of the equivalent confocal pinhole 8 can be reduced.

[0097] Optionally, the beam splitting optical element splits the light beam in the optical path. The beam splitting optical element can be all optical elements that can split a light beam, such as a beam splitting plate, a beam splitting cube, a polarization beam splitting plate, a polarization beam splitting cube, etc.

[0098] As Figure 5 As shown, without loss of generality, the objective lens 11 is used to collect the detection light emitted from the object point 5. After passing through the objective lens 11, the detection light is split into two beams by the beam splitting plate 9. These two first detection lights and the second detection light are then each reflected by the mirror 10 to the same tube lens 13, and are focused by the tube lens 13 to the position of the same image point 7 on the image plane 6. These two detection lights will interfere at the position of the image point 7, and then pass through the pinhole 8 on the image plane 6 and are received by the detector 3. Optionally, a phase retarder 12 can be set on the optical paths of the two detection lights to adjust their respective phases, thereby adjusting the interference influence effect distribution function w(x, y).

[0099] In this embodiment, the objective lens 11 includes but is not limited to an infinity objective lens, a finite conjugate objective lens, etc.

[0100] As Figure 5 As shown in the example method, by using more beam splitting plates 9 for beam splitting, a beam splitting module 2 with more split beams can be obtained, not limited to splitting into two beams. And each of the split light beams can be arranged not only along the x direction but also along the y direction.

[0101] As an example, the implementation manner of the beam splitting module 2 further includes but is not limited to imaging the object point 5 on the object plane 4 onto the relay image plane 17 through the optical system 1 first, and then placing a diffraction optical element at the relay image plane 17. The detection light emitted from the object point 5 is imaged on the relay image plane 17 and is diffracted by the diffraction optical element to form multi-stage diffracted light with different directions, thereby achieving the purpose of beam splitting. Then, the relay mirror is used to image the image point 7 on the relay image plane 17 to the image point 7 on the image plane 6. The diffraction optical element can be all optical elements that can diffract and split a light beam, such as a diffraction grating, a metasurface element, etc.

[0102] As an example, as Figure 6As shown, it is an example of implementing the beam splitting module 2 using a diffraction grating. In Figure 6 the detection light emitted from the object point 5 passes through the optical system 1 and is imaged on the image point 7 of the relay image plane 17, and is diffracted and split into multiple multi-level diffracted beams with different propagation angles by the diffraction grating placed on the relay image plane 17. These diffracted beams are collimated by the first relay mirror 14 and pass through the aperture 16 provided behind the first relay mirror 14, and the aperture 16 filters out the ±1st order diffracted light. These two diffracted beams are the first detection light and the second detection light in the figure. These two detection lights are incident on the same second relay mirror 15 and are focused by the second relay mirror 15 to the position of the same image point 7 on the image plane 6. These two detection lights will interfere at the position of the image point 7, and then are received by the detector 3 after passing through the pinhole 8 on the image plane 6. Optionally, a phase retarder 12 can be provided on the optical paths of the two detection lights to adjust their respective phases, thereby adjusting the interference influence effect distribution function w(x, y).

[0103] According to Figure 6 the method shown, by making the aperture 16 filter out more diffracted beams, a beam splitting module 2 with more beam splitting can be obtained, not limited to splitting into two beams only. And each of the split beams can be arranged not only along the x direction but also along the y direction.

[0104] This embodiment only considers the x direction parallel to the paper plane and perpendicular to the optical axis, without considering the y direction perpendicular to the paper plane. If the y direction is considered, it can be analogized accordingly. This embodiment only discusses the case of a single-pixel detector, a single pinhole, and single-focus illumination. For the cases of using a multi-pixel detector, an array of pinholes, multi-focus illumination, etc., it can be analogized accordingly. All dimensions in this embodiment are normalized to the object space for discussion.

[0105] As an example, as Figure 7 shown in the confocal imaging system, the objective lens 11 is used to collect the detection light emitted from the object point 5. After passing through the objective lens 11, the detection light is split into two beams with equal intensity by the beam splitter 9. These two first detection light and second detection light are then reflected by the mirror 10 to the same tube lens 13 respectively and are focused by the tube lens 13 to the position of the same image point 7 on the image plane 6. The confocal imaging system makes a scanning motion relative to the object plane 4, and the detector 3 can move or be stationary relative to the object plane 4. As Figure 7 shown, the mirrors 10 are arranged so that the interval between these two detection lights is 0 and they enter the tube lens 13 side by side. These two detection lights will interfere at the position of the image point 7, and then are received by the detector 3 after passing through the pinhole 8 on the image plane 6. The detector 3 is a single-pixel detector, and the pinhole 8 is a single circular pinhole with a transmittance of 1 everywhere within the circumference range and a transmittance of 0 everywhere outside the circumference range. The center position of the pinhole 8 is set at the place where the optical path from the image point 7 to the object point 5 of the first detection light path is equal to the optical path from the image point 7 to the object point 5 of the second detection light path.

[0106] The detection light emitted from the conjugate object point corresponding to the center of the pinhole 8 is split into a first detection light and a second detection light and imaged on the image plane 6. Since the optical paths of the first detection light and the second detection light from the center of the pinhole 8 to the object point 5 are equal, the wavefront phases of the first detection light and the second detection light are equal everywhere, and they can be coherently synthesized everywhere. The aperture of the beam jointly synthesized by them is twice that of the original single beam of light. Therefore, the diameter of the focused spot at the image point 7 is half of the original. At this time, when the diameter of the pinhole 8 is taken as 0.5 AU, the light transmission efficiency of using a pinhole 8 with a diameter of 1 AU when there is only a single beam of light originally can be obtained. 1 AU is the size of one Airy disk diameter. It can be seen that this method improves the light transmission efficiency of the confocal system. At this time, the pinhole transmittance distribution function h(x) can be expressed as the following formula:

[0107]

[0108] The interference influence effect distribution function w(x) at this time can be expressed by the following formula:

[0109]

[0110] where NA is the numerical aperture of the objective lens and λ is the wavelength of the detection light. It can be seen from the above formula that w(x) takes as the period, and this period is less than 0.5 AU.

[0111] The equivalent confocal pinhole function is:

[0112]

[0113] It can be seen from the above formula that the full width at half maximum of the equivalent confocal pinhole function w(x)·h(x) is only about 0.25 AU or so, which is much smaller than 1 AU. Therefore, the convolution broadening effect of the equivalent confocal pinhole function of this system on the detection point spread function PSF em (x,y,z) has been greatly weakened, but the light transmission efficiency still remains very high.

[0114] It can be obtained from formula (3):

[0115] PSF sys (x) = PSF ex (x) × {PSF em (x) * [w(x) × h(x)]} ≈ PSF ex (x) × PSF em (x)

[0116] When PSF ex (x) and PSF em (x) are approximately equal and both are the diffraction-limited Airy disk distribution, PSF sys (x) is approximately Doubled resolution improvement.

[0117] When the PSF ex (x) is in other distribution function forms (such as Bessel function, lattice structured light function, etc.), the system still has the effect of improving resolution or light utilization efficiency.

[0118] Optionally, in the case of multiple detection beams, for example, when the detection beam is divided into n beams, the intensities of the n beams are equal, tightly arranged in the x-axis direction, and the interval between adjacent two beams is zero. And assuming that the origin of the x-axis coordinate is located at the center of the pinhole 8, for all n imaging channels corresponding to the n beams, the optical paths from the center of the pinhole 8 to their corresponding conjugate object points are all equal.

[0119] Set the object-image conjugate points where the optical paths of all n imaging channels are equal, and set the image point 7 where the optical paths between the object-image conjugate points of all n imaging channels are equal as the coordinate origin. The position of the coordinate origin is the position where the main interference peak is located. According to the above setting where each beam is tightly arranged side by side, the main interference peak will repeat at as the period, and the full width at half maximum of the main interference peak is inversely proportional to the number of beams n. According to the distribution function w(x, y) of the interference influence effect and it can be known that when n beams are tightly arranged side by side in the x direction and have equal intensities:

[0120]

[0121] When n = 2,

[0122]

[0123] That is, it conforms to the above formula, requiring a pair of object-image conjugate points for all n imaging channels, and for all these n imaging channels, the optical paths of this pair of object-image conjugate points are equal.

[0124] The formula for two-beam interference in the embodiments of the present invention is a special case of the formula for n-beam interference above. The conclusions in the embodiments of the present invention can all be deduced from the formula. The period of the interference function can be obtained, and the conclusion that the full width at half maximum of the main interference peak is inversely proportional to the number of beams can be obtained.

[0125] Embodiment 3

[0126] In this embodiment, only the x direction parallel to the paper surface and perpendicular to the optical axis is considered, without considering the y direction perpendicular to the paper surface. If the y direction is considered, it can be deduced by analogy. This embodiment only discusses the case of a single-pixel detector, a single pinhole, and single-focus illumination. For the cases of using a multi-pixel detector, an array of pinholes, multi-focus illumination, etc., it can be deduced by analogy. All dimensions in this embodiment are normalized to the object space for discussion.

[0127] Such as Figure 8As shown in the confocal imaging system, the detection light emitted from the object point 5 forms an image at the image point 7 on the relay image plane 17 after passing through the optical system 1, and is diffracted and split into multiple multi-level diffracted beams with different propagation angles by the diffraction grating placed on the relay image plane 17. These diffracted beams are collimated by the first relay mirror 14 and pass through the aperture 16 provided behind the first relay mirror 14. The aperture 16 filters out the ±1st order diffracted light. These two diffracted beams are the first detection light and the second detection light in the figure. These two detection lights are incident on the same second relay mirror 15 and are focused by the second relay mirror 15 to the position of the same image point 7 on the image plane 6. These two detection lights will interfere at the position of the image point 7, and then are received by the detector 3 after passing through the pinhole 8 on the image plane 6. The confocal imaging system performs a scanning motion relative to the object plane 4, and the detector 3 can move or be stationary relative to the object plane 4.

[0128] The detector 3 is a single-pixel detector, and the pinhole 8 is a single circular pinhole with a transmittance of 1 everywhere within the circumference range and 0 everywhere outside the circumference range. The diffraction grating is a checkerboard grating (CG), and its size of each grid is set to The checkerboard grating theoretically has no zero-order diffracted light. Therefore, the ±1st order light can be filtered out through the hollow aperture 16. The center of the pinhole 8 and the center of a certain grid on the checkerboard grating are set to be conjugate imaging relationships. In this way, when the detection light emitted from the object point conjugate to the center of the pinhole 8 forms an image on the relay image plane 17, its image point 7 will fall on the center of this grid of the checkerboard grating.

[0129] It is easy to know that under this size parameter, the ±1st order diffracted lights obtained after the detection light emitted from the object point conjugate to the center of the pinhole 8 is diffracted and split by the checkerboard grating, that is, the first detection light and the second detection light, have a spacing of 0 between them. And after leaving the checkerboard grating, the phases of their wavefronts at each place are equal. Therefore, they can be coherently synthesized everywhere. The aperture of the beam synthesized by them together is 2 times that of the original single beam of light. Therefore, the diameter of the focused spot at the image point 7 is half of the original. At this time, when the diameter of the pinhole 8 is taken as 0.5 AU, the light transmittance efficiency of using a pinhole 8 with a diameter of 1 AU when there is only a single beam of light can be obtained. 1 AU is the size of 1 times the Airy disk diameter. It can be seen that this method improves the light transmittance efficiency of the confocal system. At this time, the pinhole transmittance distribution function h(x) can be expressed as the following formula:

[0130]

[0131] It is easy to know that the interference influence effect distribution function w(x) at this time can be expressed by the following formula:

[0132]

[0133] where NA is the numerical aperture of the optical system and λ is the wavelength of the detection light. It can be seen from the above formula that w(x) has a period of which is less than 0.5 AU.

[0134] The equivalent confocal pinhole function is:

[0135]

[0136] It can be seen from the above formula that the full width at half maximum of the equivalent confocal pinhole function w(x)·h(x) is only about 0.25 AU, which is much less than 1 AU. Therefore, the convolution broadening effect of the equivalent confocal pinhole function of this system on the detection point spread function PSF em (x, y, z) has been greatly weakened, but the light transmission efficiency remains very high.

[0137] From formula (3), we can get:

[0138] PSF sys (x) = PSF ex (x) × {PSF em (x) * [w(x) × h(x)]} ≈ PSF ex (x) × PSF em (x)

[0139] When PSF ex (x) is approximately equal to PSF em (x), and both are the diffraction-limited Airy disk distribution, PSF sys (x) has approximately times the resolution improvement.

[0140] Of course, when PSF ex (x) is in the form of other distribution functions (such as Bessel functions, lattice structured light functions, etc.), this system still has the effect of improving the resolution or light utilization rate.

[0141] Example 4

[0142] Chinese Patent CN112230412B discloses a fast structured light illumination super-resolution imaging system. This system is essentially a multi-focus confocal imaging system using a multi-pixel detector such as a camera. Dense periodic illumination foci are generated through structured light illumination, and the interval between the foci can be only An array of pinholes is arranged on the image plane, and the pinhole pitch can also be set to There is a one-to-one conjugate object-image relationship between a single focus and a single pinhole.

[0143] According to the above discussion, this system also has the limitation of mutual restriction among the pinhole size, light utilization efficiency, and imaging resolution. The smaller the pinhole size, the lower the light utilization efficiency, and the higher the imaging resolution, and vice versa.

[0144] This embodiment is a specific implementation method adopted to solve the above limitations. This embodiment only considers the x - direction parallel to the paper surface and perpendicular to the optical axis, without considering the y - direction perpendicular to the paper surface. If the y - direction is considered, the same principle can be extended accordingly. All dimensions in this embodiment are normalized to the object space for discussion.

[0145] As Figure 9 shown in the confocal imaging system, the detection light emitted from the object point 5 passes through the optical system 1 and is imaged on the image point 7 of the relay image plane 17, and is diffracted and split into multiple multi - level diffracted beams with different propagation angles by the diffraction grating placed on the relay image plane 17. These diffracted beams are collimated by the first relay mirror 14 and pass through the aperture 16 set behind the first relay mirror 14. The aperture 16 filters out the ±1 - order diffracted light. These two diffracted beams are the first detection light and the second detection light in the figure. These two detection lights are incident on the same second relay mirror 15 and are focused by the second relay mirror 15 to the position of the same image point 7 on the image plane 6. These two detection lights will interfere at the position of the image point 7, and then are received by the detector 3 after passing through the pinhole 8 on the image plane 6. The confocal imaging system makes a scanning motion relative to the object plane 4, and the detector 3 is stationary relative to the object plane 4.

[0146] The detector 3 is a multi - pixel detector, and the illumination light is a linear structured light, generating multiple periodically arranged illumination foci, and the distance between the foci is The illumination point spread function PSF ex (x) can be expressed as:

[0147]

[0148] The pinhole 8 is a periodic array composed of multiple circular pinholes, and the interval between each pinhole 8 is There is a one - to - one conjugate object - image relationship between the center of each pinhole 8 and the center of each illumination light focus. For a single circular pinhole in the array, the transmittance is 1 everywhere within the circumference range and 0 everywhere outside the circumference range.

[0149] The diffraction grating is a checkerboard grating (CG), and it is set that the size of each grid is Theoretically, there is no zero-order diffracted light in the checkerboard grating. Therefore, the ±1-order light can be filtered out through the hollow aperture 16. It is set that the centers of the respective pinholes 8 and the centers of the respective cells on the checkerboard grating are also conjugate object-image relationships one by one. In this way, a one-to-one conjugate object-image relationship is established among the illumination foci centers of the illumination light, the centers of the respective checkerboard grating cells, and the centers of the respective pinholes 8. It is set that the center of a certain pinhole 8 is located at the origin of coordinates.

[0150] When the detection light emitted from the object point conjugate to the center of a certain pinhole 8 is imaged onto the relay image plane 17, its image point 7 will fall on the center of a corresponding cell on the checkerboard grating.

[0151] It is easy to know that under this size parameter, the ±1-order diffracted lights obtained after the detection light emitted from the conjugate object point corresponding to the center of a certain pinhole 8 is diffracted and split by the checkerboard grating, that is, the first detection light and the second detection light, have a spacing of 0 between them. And after leaving the checkerboard grating, the phases of their wavefronts at each place are equal. Therefore, they can be coherently synthesized everywhere. The aperture of the beam synthesized by them together is twice the aperture of the original single beam of light. Therefore, the diameter of the focused spot at the image point 7 is half of the original. At this time, when the diameter of the pinhole 8 is taken as 0.5 AU, the light transmission efficiency of using a pinhole 8 with a diameter of 1 AU when there is only a single beam of light originally can be obtained. 1 AU is the size of 1 times the Airy disk diameter. It can be seen that this method improves the light transmission efficiency of the confocal system. At this time, the transmittance distribution function h s (x) of a single pinhole with its center located at the origin of coordinates can be expressed as the following formula:

[0152]

[0153] It is easy to know that the interference influence effect distribution function w(x) at this time can be expressed by the following formula:

[0154]

[0155] Among them, NA is the numerical aperture of the optical system, and λ is the wavelength of the detection light. It can be seen from the above formula that w(x) has as the period, and this period is less than 0.5 AU.

[0156] The single equivalent confocal pinhole function with its center located at the origin of coordinates is:

[0157]

[0158] It can be seen from the above formula that the full width at half maximum of the single equivalent confocal pinhole function w(x)·h s (x) of the pinhole with its center located at the origin of coordinates is only about 0.25 AU or so, which is much smaller than 1 AU. Therefore, the single equivalent confocal pinhole function of this system for the detection point spread function PSF ex(x,y,z) The convolution broadening effect has been greatly weakened, but the light transmission efficiency still remains very high.

[0159] From Equation (4), considering symmetry, the convolution of the equivalent pinhole array 18 with the corresponding focal point array, after normalization, is equal to the convolution of a single equivalent confocal pinhole function with its pinhole center at the origin of coordinates with this focal point array. Therefore, the following equation can be obtained:

[0160]

[0161] From the above equation, it can be known that Part retains more high-frequency components, and the PSF sys (x) has a two-fold resolution improvement compared to wide-field imaging. The period interval of the above-mentioned pinhole array 18 is less than 0.5 AU. In fact, the light-transmitting apertures between adjacent pinholes have partially overlapped, that is, it can be considered that the pinholes actually do not exist.

[0162] Next, calculate the PSF sys (x) of the system from the perspective of directly removing the pinhole array 18. It can be noted that if the pinhole array 18 is removed, it is equivalent to setting the transmittance of the pinhole array 18 to 1 everywhere.

[0163]

[0164] From the above equation, it can be known that Part also retains more high-frequency components. Therefore, removing the pinhole array 18, the PSF sys (x) also has a two-fold resolution improvement compared to wide-field imaging.

[0165] Example 5

[0166] Next, refer to Figure 10 , which shows a structural diagram of an electronic device 300 suitable for implementing the embodiments of the present application. The electronic device is intended to represent various forms of digital computers, such as, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, personal digital processors, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only examples and are not intended to limit the implementation of the present application described herein and / or required.

[0167] As Figure 10As shown, the electronic device 300 may include a processing device 310, which may perform various appropriate actions and processes according to programs stored in a read-only memory (ROM) 320 or programs loaded from a storage device 380 into a random access memory (RAM) 330. The processing device 310 may be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the processing device 310 include, but are not limited to, a central processing unit (CPU), a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any appropriate processor, controller, microcontroller, etc. The processing device 310 executes the various methods and processes described above.

[0168] In the RAM 330, various programs and data required for the operation of the electronic device 300 are also stored. The processing device 310, the ROM 320, and the RAM 330 are connected to each other through a bus 340. An input / output (I / O) interface 350 is also connected to the bus 340.

[0169] Generally, the following devices may be connected to the I / O interface 350: an input device 360 including, for example, a touch screen, a touchpad, a keyboard, a mouse, a camera, a microphone, an accelerometer, a gyroscope, etc.; an output device 370 including, for example, a liquid crystal display (LCD), a speaker, a vibrator, etc.; a storage device 380 including, for example, a magnetic tape, a hard disk, etc.; and a communication device 390. The communication device 390 may allow the electronic device 300 to communicate with other devices wirelessly or wireline to exchange data. Although Figure 10 an electronic device 300 with various devices is shown, it should be understood that it is not required to implement or have all the shown devices. More or fewer devices may be implemented or had alternatively.

[0170] In particular, according to an embodiment of the present application, the process described above with reference to the flowchart can be implemented as a computer software program. For example, an embodiment of the present application includes a computer program product, which includes a computer program carried on a non-transitory computer-readable medium, and the computer program includes program codes for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from a network through a communication device 390, or installed from a storage device 380, or installed from a ROM 320. When the computer program is executed by a processing device 310, the above functions defined in the method of the embodiment of the present application are executed. Alternatively, in other embodiments, the processing device 310 can be configured to execute the method in any other suitable manner (for example, by means of firmware): a beam splitting module is set in a confocal imaging system, and the detection light emitted by an object point is split by the beam splitting module, and the detection light is split into at least two beams, and at least two beams of detection light are imaged onto an image plane through at least two different imaging channels; a single imaging channel generates a single independent image point on the image plane, at least two image points coincide in position on the image plane, interference occurs at the position of the coincident image points, and after passing through a pinhole on the image plane, it is received by a detector; at least two beams of detection light interfere with each other to cause a change in the intensity of the image point to form an interference effect, and the distribution function of the interference effect is w(x, y), and the interference effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process; the distribution of the detection light passing through the pinhole is modulated by the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y).

[0171] Embodiment 6

[0172] The computer-readable medium described above in this application can be a computer-readable signal medium, a computer-readable storage medium, or any combination of the two. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any combination of the above. More specific examples of a computer-readable storage medium can include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this application, a computer-readable storage medium can be any tangible medium that contains or stores a program, which can be used by or in conjunction with an instruction execution system, apparatus, or device. And in this application, a computer-readable signal medium can include a data signal propagated in a baseband or as part of a carrier wave, which carries computer-readable program code. Such a propagated data signal can take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium can also be any computer-readable medium other than a computer-readable storage medium, which can send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on a computer-readable medium can be transmitted using any appropriate medium, including but not limited to: wires, optical cables, RF (radio frequency), etc., or any suitable combination of the above.

[0173] In some embodiments, the client and the server can communicate using any currently known or future-developed network protocol such as HTTP (HyperText Transfer Protocol), and can be interconnected with digital data communication in any form or medium (e.g., a communication network). Examples of communication networks include local area networks ("LANs"), wide area networks ("WANs"), the Internet (e.g., the Internet), and end-to-end networks (e.g., ad hoc end-to-end networks), as well as any currently known or future-developed networks.

[0174] The above computer-readable medium can be included in the above electronic device; or it can exist separately without being assembled into the electronic device.

[0175] The above computer-readable medium carries one or more programs, which, when executed by the electronic device, cause the electronic device to: set a beam splitting module in a confocal imaging system, split the detection light emitted by an object point through the beam splitting module, divide the detection light into at least two beams, and image at least two beams of detection light into at least two different imaging channels onto an image plane; a single imaging channel generates a single independent image point on the image plane, at least two image points coincide in position on the image plane, interference occurs at the position of the coincident image points, and after passing through a pinhole on the image plane, they are received by a detector; at least two beams of detection light interfere to cause a change in the intensity of the image point to form an interference influence effect, the distribution function of the interference influence effect is w(x, y), and the interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process; modulate the distribution of the detection light after passing through the pinhole through the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y).

[0176] Computer program code for performing the operations of the present application may be written in one or more programming languages or combinations thereof. The programming languages include, but are not limited to, object-oriented programming languages such as Java, Smalltalk, C++, and also include conventional procedural programming languages such as the "C" language or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, executed as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., via an Internet service provider through the Internet).

[0177] The flowcharts and block diagrams in the accompanying drawings illustrate the possible architectures, functions, and operations of systems, methods, and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagram may represent a module, a segment of a program, or a portion of code that contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions noted in the blocks may occur in a different order than noted in the accompanying drawings. For example, two consecutive blocks shown may actually be executed substantially in parallel, and they may sometimes be executed in the reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented by a dedicated hardware-based system that performs the specified functions or operations, or by a combination of dedicated hardware and computer instructions.

[0178] The modules described in the embodiments of the present application can be implemented in software or in hardware. Among them, the name of the module does not constitute a limitation to the module itself in some cases.

[0179] The functions described above in this document can be performed, at least in part, by one or more hardware logic components. For example, without limitation, exemplary types of hardware logic components that can be used include: digital electronic circuitry, integrated circuit systems, field programmable gate arrays (FPGA), application specific integrated circuits (ASIC), application specific standard products (ASSP), systems on a chip (SOC), complex programmable logic devices (CPLD), computer hardware, firmware, software, and / or combinations thereof, and so on.

[0180] The program code for implementing the methods of the present application can be written in any combination of one or more programming languages. These program codes can be provided to the processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the program codes are executed by the processor or controller, the functions / operations specified in the flowchart and / or block diagram are implemented. The program code can be executed entirely on the machine, partially on the machine, as a stand-alone software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0181] In the context of this application, a machine-readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium can include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. More specific examples of the machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0182] In order to provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or a trackball) by which the user can provide input to the computer. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, speech input, or tactile input).

[0183] The systems and techniques described herein can be implemented in a computing system that includes backend components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes frontend components (e.g., a user computer having a graphical user interface or a web browser through which the user can interact with an implementation of the systems and techniques described herein), or a computing system that includes any combination of such backend components, middleware components, or frontend components. The components of the system can be interconnected to each other by any form or medium of digital data communication (e.g., a communication network). Examples of communication networks include: local area network (LAN), wide area network (WAN) blockchain network, and the Internet.

[0184] A computer system may include a client and a server. The client and the server are generally far from each other and usually interact via a communication network. The client-server relationship is created by computer programs running on respective computers and having a client-server relationship with each other. The server can be a cloud server, also known as a cloud computing server or a cloud host, which is a host product in the cloud computing service system, addressing the defects of difficult management and weak business scalability existing in traditional physical hosts and VPS services. The server can also be a server of a distributed system or a server combined with blockchain.

[0185] Artificial intelligence is a discipline that studies how to make computers simulate certain human thinking processes and intelligent behaviors (such as learning, reasoning, thinking, planning, etc.), with both hardware-level and software-level technologies. Artificial intelligence hardware technologies generally include technologies such as sensors, dedicated artificial intelligence chips, cloud computing, distributed storage, and big data processing; artificial intelligence software technologies mainly include several major directions such as computer vision technology, speech recognition technology, natural language processing technology, machine learning / deep learning technology, big data processing technology, and knowledge graph technology.

[0186] Cloud computing refers to a technical system that enables elastic and scalable shared physical or virtual resource pools to be accessed via a network. The resources can include servers, operating systems, networks, software, applications, and storage devices, etc., and the resources can be deployed and managed in a demand-based and self-service manner. Through cloud computing technology, it is possible to provide efficient and powerful data processing capabilities for the application and model training of technologies such as artificial intelligence and blockchain.

[0187] The embodiments described above are some, but not all, of the embodiments of the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts fall within the scope of protection of the embodiments of the present application.

[0188] In the description of the embodiments of the present application, it should be noted that the orientation or positional relationship indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of this application is usually placed during use. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the electric vehicle or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention. In addition, terms such as "first", "second", "third", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0189] In the description of the embodiments of the present application, it should also be noted that, unless otherwise clearly specified and limited, the terms "set", "installed", "connected", and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0190] Finally, it should be noted that the above embodiments are only specific embodiments of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: any person skilled in the art within the technical scope disclosed by the present application can still modify the technical solutions recorded in the foregoing embodiments, or can easily conceive of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. An equivalent confocal pinhole imaging method, characterized in that, It includes the following steps: Set a beam splitting module in a confocal imaging system. Split the detection light emitted by an object point through the beam splitting module, divide the detection light into at least two beams, and image at least two beams of detection light into at least two different imaging channels onto an image plane; The detection light emitted by the object point generates a single independent image point on the image plane through a single imaging channel. At least two image points coincide in position on the image plane, interference occurs at the position of the coincident image points, and after passing through the pinhole on the image plane, it is received by a detector; Interference between at least two detection light beams causes a change in the intensity of the image point to form an interference influence effect. The distribution function of the interference influence effect is w(x, y), and the interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process; Modulate the distribution of the detection light passing through the pinhole through the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y).

2. The equivalent confocal pinhole imaging method according to claim 1, characterized in that, The modulation of the distribution of the detection light passing through the pinhole through the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y) includes: Set the interference influence effect distribution function w(x, y) and the pinhole transmittance distribution function h(x, y) so that the part where the value of the interference influence effect distribution function w(x, y) is the largest or close to the largest coincides with the part where the value of the pinhole transmittance distribution function h(x, y) is the largest or close to the largest.

3. The equivalent confocal pinhole imaging method according to claim 1, characterized in that Determine the optical path difference between the imaging channels, the relative intensity distribution of the imaging channels, and the spatial position distribution of the imaging channels according to the settings of the beam splitting module. Determine the interference influence effect distribution function w(x, y) according to the optical path difference between the imaging channels, the relative intensity distribution of the imaging channels, and the spatial position distribution of the imaging channels.

4. The equivalent confocal pinhole imaging method according to claim 1, wherein, Perform phase delay on the single imaging channel and adjust the phase difference between each detection light beam to adjust the interference influence effect distribution function w(x, y).

5. An equivalent confocal pinhole imaging method according to claim 1, characterized in that, The way the detector generates a confocal image includes that the intensity of the detection light signal received by the detector changes with time, and confocal image information is obtained by reconstructing the signal that changes with time.

6. The equivalent confocal pinhole imaging method according to claim 5, characterized in that, It also includes that pixels at at least two different spatial positions on the detector receive signal light at different spatial positions, and the received signals are processed to obtain confocal image information.

7. An equivalent confocal pinhole imaging system, which applies an equivalent confocal pinhole imaging method as described in claims 1-6, is characterized in that, It includes an optical system, a beam splitting module, and a detector arranged in sequence along the optical path. Among them, The illumination light emitted by the optical system illuminates the object plane, and the object point on the object plane emits detection light, and the detection light passes through the optical system; The beam splitting module splits the detection light emitted by the object point and passing through the optical system, divides the detection light into at least two beams, and images at least two beams of detection light into at least two different imaging channels onto the image plane. A single imaging channel generates a single independent image point on the image plane. At least two image points coincide in position on the image plane, interference occurs at the position of the coincident image points, and after passing through the pinhole on the image plane, it is received by the detector; At least two detection light beams interfere with each other, resulting in a change in the intensity of the image point to form an interference influence effect. The distribution function of the interference influence effect is w(x, y). The interference influence effect distribution function w(x, y) remains fixed relative to the pinhole transmittance distribution function h(x, y) during the confocal scanning process. By setting the equivalent confocal pinhole transmittance distribution function w(x, y)×h(x, y), the distribution of the detection light after passing through the pinhole is modulated, so that the part where the value of the interference influence effect distribution function w(x, y) is the largest or close to the largest coincides with the part where the value of the pinhole transmittance distribution function h(x, y) is the largest or close to the largest.

8. An equivalent confocal pinhole imaging system according to claim 1, characterized in that, It further includes a phase delay unit, which is arranged on the optical path between the beam splitting module and the detector, and is used to adjust the phase difference between each detection light beam to adjust the interference influence effect distribution function w(x, y).

9. An electronic device, characterized in that, It includes a memory and a processor. The memory stores a program that runs on the processor. When the processor runs the program, it executes an equivalent confocal pinhole imaging method according to claims 1-6.

10. A computer-readable storage medium having computer instructions stored thereon, characterized in that, When the computer instructions run, they execute an equivalent confocal pinhole imaging method according to claims 1-6.

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