Wide-field-of-view and wide-band inclined microscopic imaging defocus correction device and method

Abstract

The invention discloses a wide-field-of-view and wide-band inclined microscopic imaging defocus correction device and method. The device comprises a light incidence module, a defocus correction module, a light emergence module and an image analysis and processing module, the defocus correction module comprises one or two off-axis parabolic mirrors; at least one of the light incident module and the light emergent module is of an inclined imaging structure, namely, the optical axis of an imaging light path is not perpendicular to an imaging object plane. The imaging defocus problem caused by inclined imaging is corrected through the defocus correction module; image distortion introduced by the defocus correction module is corrected through the image analysis processing module; finally, a wide-field-of-view, wide-band, full-field-of-view and full-band clear distortionless imaging effect is realized.

Description

Technical Field

[0001] The present invention relates to the field of optical imaging technology, and particularly to a wide-field, wide-bandwidth tilt microscopic imaging defocus correction device and method. Background Art

[0002] Optical imaging has become an indispensable technical means and tool in modern industry, life, technology, etc. In conventional optical imaging, the imaging object plane is generally perpendicular to the optical axis of the imaging system. However, in some practical applications, such as surface plasmon resonance imaging, total internal reflection imaging, ellipsometry imaging, polarization-dependent imaging, etc., the optical axis of the imaging system forms an inclined angle with the imaging object plane. At this time, due to the limited depth of field of the imaging lens, when performing wide-field imaging, it will cause the object plane to be defocused, resulting in blurred imaging, and different magnification ratios at different depths of field, resulting in image distortion. This problem is particularly significant in wide-field microscopic imaging. Since the larger the magnification of the objective lens, the smaller the depth of field, it is difficult to achieve high-magnification microscopic imaging in an inclined imaging system.

[0003] Currently, only an ordinary imaging lens cannot obtain good imaging effects in an inclined imaging system. Some existing solutions generally design imaging lenses based on Scheimpflug's law to achieve inclined imaging, as described in, for example, the publications with publication numbers CN201477280U, CN112269242A, CN115097605A, and JP201900741. However, this type of method has a complex lens structure design and requires a combination of multiple lenses to achieve a relatively good imaging effect. The processing cost is extremely high, making it difficult to promote and use. Moreover, most designs are not applicable to microscopic imaging, and the wider the imaging band, the greater the design difficulty.

[0004] The problem of defocus of the object field of view in inclined imaging can be corrected on the basis of an existing ordinary imaging lens through diffraction devices such as gratings. However, due to the wavelength dependence of the characteristics of diffraction devices, this solution is only applicable to defocus correction of monochromatic light inclined imaging and is limited in application in wide-bandwidth imaging. In addition, diffraction devices also have the problem of low diffraction efficiency, resulting in a decrease in light utilization rate. Summary of the Invention

[0005] The present invention provides a wide-field, wide-bandwidth tilt microscopic imaging defocus correction device and method, which can achieve clear and distortion-free imaging effects for the entire field of view and the entire band in wide-field and wide-bandwidth.

[0006] A wide-field, wide-bandwidth tilt microscopic imaging defocus correction device includes a light incident module, a defocus correction module, a light output module, and an image analysis and processing module; Among them, the light incident module adopts a general illumination module or an imaging illumination module; when the general illumination module is adopted, the incident imaging optical path is not defocus corrected; when the imaging illumination module is adopted, the included angle between the incident imaging optical path and the normal line of the imaging object is When or it is frontal imaging and no defocus correction is performed; when and it is tilted imaging, and a first off-axis parabolic mirror is arranged between the light incident module and the imaging object; The light exit module includes a beam shaping and imaging module and a detector, and the included angle between the exiting imaging optical path and the normal line of the imaging object is , and it is tilted imaging, and a second off-axis parabolic mirror is arranged between the imaging object and the light exit module; The off-axis angle of the first off-axis parabolic mirror is and and its placement direction satisfies that its meridian plane coincides with the light incident plane on the imaging object; the off-axis angle of the second off-axis parabolic mirror is and and its placement direction satisfies that its meridian plane coincides with the light exit plane on the imaging object; The described image analysis and processing module is connected to the detector and is used to correct the image distortion introduced by the exit defocus correction module.

[0007] In the present invention, the application scope of the defocus correction module and the image analysis and processing module includes but is not limited to microscopic imaging systems, telescopic imaging systems, etc.

[0008] When the light incident module adopts a general illumination module, it includes a light source and a beam shaping module. Among them, the beam shaping module is used to adjust the spot size and shape of the light source irradiating the imaging object, or the energy distribution and wavelength range of the spot in the spatial domain, time domain, and frequency domain.

[0009] The light source includes but is not limited to the self-luminescence of the imaging object, ambient illumination light, active and passive illumination, coherent or incoherent light. For example, the autofluorescence of the object, LED light illumination, or laser illumination, etc.

[0010] When the light incident module adopts an imaging illumination module, a beam imaging module is added on the basis of the general illumination module. Among them, the beam imaging module is used to perform amplitude or phase patterning modulation on the illumination light after passing through the beam shaping module and image it onto the imaging object.

[0011] In the light emitting module, the beam shaping and imaging module is used to collect the emitted light from the imaging object, image the imaging object, magnify or reduce the image during imaging, or modulate the amplitude or phase of the light in the spatial, temporal, or frequency domain of the imaging plane or imaging optical path.

[0012] In the light emitting module, the detector is a photoelectric conversion detector, which is used to receive and collect the emitted light from the imaging object collected by the beam shaping and imaging module.

[0013] The image analysis and processing module includes a distortion correction algorithm, and the formula is as follows: ; In the formula, represents the image data of the imaging object directly obtained by the detector or obtained after data processing. This image data is a two-dimensional matrix, which includes the image distortion introduced by the defocus correction module; is the total distortion correction matrix, and the formula is: ; In the formula, is the tilt projection distortion correction matrix, is the tangential stretching distortion correction matrix, and the formula is as follows: ; ; In the formula, is the angle by which the defocus correction module deflects the optical axis of the light incident module or the light emitting module. Ideally, it is equal to the off-axis angles of the first and second off-axis parabolic mirrors in the light incident and emitting directions respectively. The specific values deviated from the ideal situation due to system errors are obtained through system calibration; represents the dihedral angle formed due to the system error that the meridional plane of the off-axis parabolic mirror does not completely coincide with the light incident plane or the light emitting plane of the imaging object. Its specific value is obtained through system calibration.

[0014] When the defocus correction module is adjusted to the ideal state, , at this time . After the actual imaging system is built and debugged, there are still errors, which can be calibrated through a standard pattern to obtain the actual values of and .

[0015] When the imaging illumination module is adopted, in the light incident module, the incident optical path forms a relay imaging plane conjugate to the imaging object plane , and the distance between its parabolic center intercepted by the first off-axis parabolic mirror is the image distance , and satisfy the object-image relationship: ; wherein, is the focal length of the first off-axis parabolic mirror; represents the object distance, which is the distance between the field center on the imaging object and the center of the parabola intercepted by the first off-axis parabolic mirror; the imaging magnification introduced by the first off-axis parabolic mirror is .

[0016] In the light output module, the output light path forms a relay imaging surface conjugate to the imaging object surface , and the distance between its center and the center of the parabola intercepted by the second off-axis parabolic mirror is the image distance , and satisfy the object-image relationship: ; wherein, is the focal length of the second off-axis parabolic mirror; represents the object distance, which is the distance between the field center on the imaging object and the center of the parabola intercepted by the second off-axis parabolic mirror; the imaging magnification introduced by the second off-axis parabolic mirror is .

[0017] A defocus correction method for wide-field and wide-band tilted microscopic imaging, based on the above wide-field and wide-band tilted microscopic imaging defocus correction device, includes: In the light incident module and the light output module, at least the light output module is in a tilted imaging configuration, that is, the optical axis of the imaging light path is not perpendicular to the imaging object surface; The imaging defocus problem caused by tilted imaging is corrected by the defocus correction module; the image distortion introduced by the defocus correction module is corrected by the image analysis and processing module; finally, a clear and distortion-free imaging effect of the entire field of view and the entire band in wide field of view and wide band is achieved.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. For any tilted imaging angle, the present invention can correct the tilted defocus by designing the off-axis angle of the corresponding off-axis parabolic mirror, and the method is simple and very flexible.

[0019] 2. The defocus correction module of the present invention adopts a reflective imaging design, and there is no need to consider the imaging chromatic aberration problem in the structural design, which is very friendly to wide-band imaging.

[0020] 3. Through the improvement of adding a defocus correction module in the hardware structure, the present invention realizes clear imaging in a wide field of view, and then combines the image analysis and processing module in the algorithm to realize image de-distortion. The synergistic effect of hardware improvement and data processing method significantly reduces the difficulty and cost of the solution to the defocus problem of wide-field and wide-band tilted imaging. Moreover, this solution is compatible with the existing imaging module. Description of the Drawings

[0021] Figure 1 It is a schematic diagram of an existing conventional tilt imaging optical path.

[0022] Figure 2 It is a schematic diagram of the imaging effect of an existing conventional tilt imaging optical path.

[0023] Figure 3 It is a schematic diagram of the overall structure of a wide-field, wide-band tilt microscopic imaging defocus correction device according to an embodiment of the present invention.

[0024] Figure 4 It is a schematic diagram of an optical path in which defocus correction modules are provided for both the incident and outgoing imaging optical paths according to an embodiment of the present invention.

[0025] Figure 5 It is a schematic diagram of the meanings of the main parameters of an off-axis paraboloid mirror according to an embodiment of the present invention.

[0026] Figure 6 It is a flow chart of a distortion correction algorithm of an image analysis and processing module according to an embodiment of the present invention.

[0027] Figure 7 It is a schematic diagram of an optical path in which a defocus correction module is provided only for the outgoing imaging optical path according to an embodiment of the present invention.

[0028] Figure 8 It is the output image collected by a detector according to an embodiment of the present invention.

[0029] Figure 9 It is a schematic diagram of the effect of distortion correction of the output image through an image analysis and processing module according to an embodiment of the present invention. Detailed implementation manners

[0030] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be noted that the following embodiments are intended to facilitate the understanding of the present invention and do not limit it in any way.

[0031] As Figure 1 shown, it is an existing conventional tilt imaging optical path. The light incident module 100 is an ordinary illumination module without imaging defocus problems, and the incident angle is 25°. It includes a light source 101 and a beam shaping module composed of a lens 102, a lens 103, and a lens 104. Among them, the light source 101 is a white light LED lamp; the lenses 102 and 103 are both achromatic lenses for expanding and collimating the output light of the light source 101; the lens 103 is also an achromatic lens for focusing the collimated beam onto the imaging object.

[0032] The light emitting module 200 has an inclined imaging optical path, resulting in an imaging defocus problem, with an exit angle of 25°. It includes a beam shaping and imaging module composed of a microscope objective lens 201 and a tube lens 202, and a detector 203. Among them, both the microscope objective lens 201 and the tube lens 202 have an achromatic function, which is used to collect the emitted light from the imaging object and image the imaging object, with an imaging magnification of 10 times; the detector 203 is a grayscale area array CMOS (Complementary Metal Oxide Semiconductor) detector, which is used to collect images.

[0033] The imaging effect of using the above-mentioned existing conventional inclined imaging optical path is as Figure 2 shown. When the imaging tilt angle is 25°, within a wide field of view, only the middle area of the image can be clearly imaged, while in the left and right areas of the image, the image is blurred due to the defocus problem of the inclined imaging, and the spatial resolution becomes poor.

[0034] As Figure 3 shown, in the embodiment of the present invention, a wide field of view, wide band inclined microscopic imaging defocus correction device mainly includes a light incident module 100, a light emitting module 200, a defocus correction module 300, and an image analysis and processing module 400. Among them, the defocus correction module 300 is provided with two or one off-axis parabolic mirror according to actual needs, specifically as Figure 4 and Figure 7 shown.

[0035] As Figure 4 shown, the defocus correction module 300 is provided with two off-axis parabolic mirrors. The light incident module 100 adopts an imaging illumination module, which includes a light source 101 and a beam shaping and imaging module composed of a beam shaping module and a beam imaging module. The incident imaging optical path forms an angle of , and with the normal line of the imaging object, which is inclined imaging. A first off-axis parabolic mirror 301 and a reflector 303 are arranged between the light incident module 100 and the imaging object.

[0036] The light source 101 in the light incident module 100 includes but is not limited to the self-luminescence of the imaging object, ambient illumination light, active and passive illumination, coherent or incoherent light. For example, the autofluorescence of the object, or LED light illumination, or laser illumination, etc.

[0037] The beam shaping and imaging module composed of a beam shaping module and a beam imaging module includes, but is not limited to, lenses, lens groups, mirrors, optical modulation devices, filters, polarizers, beam splitters, etc. Its functions include, but are not limited to, adjusting the spot size or shape of the light source irradiating the imaging object, or adjusting the energy distribution and wavelength range of the spot in the spatial, temporal, and frequency domains, or performing amplitude or phase patterning modulation on the illumination light and imaging it onto the imaging object, etc. For example, a lens group is included for beam expansion or contraction of the light source spot, a digital micromirror device (DMD) included in the optical modulation device is used for light amplitude modulation in the spatial domain, and an imaging lens is used to image the modulated spatial domain image onto the imaging object; a spatial light modulator (SLM) included in the optical modulation device is used for light phase modulation in the spatial domain, and an imaging lens is used to image the modulated spatial domain image onto the imaging object, etc.

[0038] The light output module 200 includes a beam shaping and imaging module and a detector 203. The included imaging optical path makes an angle with the normal of the imaging object of , and , for tilted imaging. A second off-axis parabolic mirror 302 and a mirror 304 are provided before the imaging object and the light output module.

[0039] The beam shaping and imaging module in the light output module 200 includes, but is not limited to, lenses, lens groups, mirrors, optical modulation devices, filters, polarizers, beam splitters, etc. Its main functions are to collect the outgoing light from the imaging object, image the imaging object, and perform, during the imaging process, including but not limited to imaging magnification or reduction, light amplitude or phase modulation in the spatial, temporal, and frequency domains on the imaging surface or in the imaging optical path, etc. For example, a 50x microscope objective lens and a tube lens are included to perform 50x magnified imaging of the imaging object, a digital micromirror device (DMD) included in the optical modulation device is used for spatial domain light amplitude modulation on the image plane, and an imaging lens is used to image the modulated spatial domain image onto the detector, etc.

[0040] The detector 203 is a photoelectric conversion detector, including but not limited to single-point, linear array, and area array cameras, and is used to receive and collect the outgoing light from the imaging object collected by the beam shaping and imaging module. For example, the detector is an area array black and white complementary metal oxide semiconductor (CMOS), or an area array color CMOS, or an area array black and white charge-coupled device (CCD), a single-point photomultiplier tube (PMT), etc.

[0041] As Figure 4 and Figure 5 shown, a first off-axis parabolic mirror 301 is used for defocus correction of the incident tilted imaging optical path, and its focal length is ; the off-axis angle of the first off-axis parabolic mirror 301 is , and , the placement direction is such that its meridional plane coincides with the light incident plane on the imaging object. The distance between the center of the field of view on the imaging object and the center of the parabolic surface intercepted by the first off-axis parabolic mirror 301 is the object distance .

[0042] The second off-axis parabolic mirror 302 is used for correcting the defocus of the inclined imaging optical path, and its focal length is ; the off-axis angle of the second off-axis parabolic mirror 302 is , and , the placement direction is such that its meridional plane coincides with the light exit plane on the imaging object. The distance between the center of the field of view on the imaging object and the center of the parabolic surface intercepted by the second off-axis parabolic mirror 302 is the object distance .

[0043] In the light incident module, the incident optical path forms a relay imaging plane conjugate to the imaging object plane , and the distance between it and the center of the parabolic surface intercepted by the first off-axis parabolic mirror 301 is the image distance , and satisfy the object-image relationship: ; in the light incident direction, the imaging magnification introduced by the first off-axis parabolic mirror is .

[0044] In the light exit module, the exit optical path forms a relay imaging plane conjugate to the imaging object plane , and the distance between it and the center of the parabolic surface intercepted by the second off-axis parabolic mirror 302 is the image distance , and satisfy the object-image relationship: ; in the light exit direction, the imaging magnification introduced by the second off-axis parabolic mirror .

[0045] As Figure 6 shown, the distortion correction algorithm flow of the image analysis and processing module is as follows: The input of the image analysis and processing module is the image data of the imaging object collected by the detector, which is a two-dimensional matrix, denoted as , which contains the image distortion introduced by the defocus correction module. Optionally, is the direct output result of the detector, or the two-dimensional image data obtained after processing the output of the detector. The output of the image analysis and processing module is , which is a two-dimensional image of the imaging object without distortion. The method for distortion removal is: .

[0046] Among them, the total distortion correction matrix . Among them, The defocus correction module is used to correct the angular deflection of the optical axis of the incident optical path imaging module or the outgoing optical path imaging module caused by the image tilt projection distortion; The defocus correction module is used to correct the tangential stretching distortion caused by the non-coplanarity of the meridian plane of the off-axis parabolic mirror of the defocus correction module and the light incident surface or the light outgoing surface of the imaging object. Define the dihedral angle between the meridian plane of the off-axis parabolic mirror and the light incident surface or the light outgoing surface of the imaging object as , then the tilt projection distortion correction matrix and the tangential stretching distortion correction matrix are respectively: ; ; When the defocus correction module is adjusted to the ideal state, , at this time . After the actual imaging system is built and debugged, there are still errors, which can be calibrated through a standard pattern to obtain and actual values.

[0047] As Figure 7 shown, in another embodiment of the present invention, the defocus correction module 300 is provided with only one off-axis parabolic mirror, that is, only the second off-axis parabolic mirror 302 and the mirror 304 are provided between the imaging object and the light output module. The light incident module 100 is an ordinary illumination module without imaging defocus problems, and the incident angle is 45°. It includes a light source 101 and a beam shaping module composed of a lens 102, a lens 103, a mirror 105, a mirror 106 and a lens 107.

[0048] Among them, the light source 101 is a white light LED lamp; both the lens 102 and the lens 103 are achromatic lenses, which are used to expand and collimate the output light of the light source 101; the mirrors 105 and 106 are plane mirrors, which are used to change the propagation direction of the light beam; the lens 107 is an achromatic lens, which is used to focus the collimated light beam onto the imaging object.

[0049] The outgoing optical path is an inclined imaging optical path with imaging defocus problems, and the outgoing angle is 45°.

[0050] The light output module 200 includes a beam shaping and imaging module composed of a microscopic objective lens 201 and a tube lens 202, and a detector 203. Among them, both the microscopic objective lens 201 and the tube lens 202 have achromatic functions, which are used to collect the outgoing light on the imaging object and image the relay image plane , and the imaging magnification is 10 times; the detector 203 is a grayscale area array CMOS (Complementary Metal Oxide Semiconductor) detector, which is used to collect images.

[0051] In the outgoing light path, a second off-axis parabolic mirror 302 and a reflecting mirror 304 are added in front of the light-emitting module 200, which are used to deflect the optical axis of the outgoing light path on the imaging object by 45°, so that the optical axis of the incident light of the light-emitting module 200 is perpendicular to the imaging object plane A, and correct the defocus problem caused by tilted imaging.

[0052] The off-axis angle of the second off-axis parabolic mirror 302 is 45°, which is used to deflect the optical axis of the outgoing light path on the imaging object by 45° and image the imaging object onto the relay image plane ; the imaging magnification is 1 times; the reflecting mirror 304 is a plane reflecting mirror, which is used to change the propagation direction of the light beam.

[0053] The detector 203 collects and outputs an image as Figure 8 shown. When the imaging tilt angle is 45°, after adopting the defocus correction module 300, within the wide field of view, all image areas are clear, indicating that the defocus problem of the field of view caused by tilted imaging is corrected; however, the second off-axis parabolic mirror 302 in the defocus correction module 300 introduces image distortion.

[0054] The imaging effect after the collected and output image is subjected to distortion correction by the image analysis and processing module is as Figure 9 shown. The distorted square pattern is restored after being processed by the distortion correction matrix .

[0055] Finally, a clear and distortion-free imaging effect of the entire field of view and the entire wavelength band with a wide field of view and a wide wavelength band is achieved.

[0056] The above-described embodiments have detailed the technical solutions and beneficial effects of the present invention. It should be understood that the above are only specific embodiments of the present invention and are not used to limit the present invention. Any modification, supplement, and equivalent replacement made within the scope of the principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A wide-field, wide-bandwidth tilt microscopic imaging defocus correction device, characterized in that, It includes a light incident module, a defocus correction module, a light output module, and an image analysis and processing module; the defocus correction module includes one or two off-axis parabolic mirrors. Among them, the light incident module adopts a general lighting module or an imaging lighting module; when the general lighting module is adopted, defocus correction is not performed on the incident imaging optical path; when the imaging lighting module is adopted, the included angle between the incident imaging optical path and the normal line of the imaging object is When or When, it is a frontal imaging, and defocus correction is not performed; when and When, it is an inclined imaging, and a first off-axis parabolic mirror is set between the light incident module and the imaging object; The light emitting module includes a beam shaping and imaging module and a detector, and the included angle between the outgoing imaging optical path and the normal line of the imaging object is , and , for inclined imaging, a second off-axis parabolic mirror is arranged between the imaging object and the light emitting module; The off-axis angle of the first off-axis parabolic mirror is , and , and its placement direction satisfies that its meridian plane coincides with the light incident plane on the imaging object; the off-axis angle of the second off-axis parabolic mirror is , and , and its placement direction satisfies that its meridian plane coincides with the light exit plane on the imaging object; The image analysis and processing module is connected to a detector and is used to correct the image distortion introduced by the defocus correction module.

2. The wide-field, wide-bandwidth tilt microscopic imaging defocus correction device according to claim 1, characterized in that, When the light incident module adopts a general illumination module, it includes a light source and a beam shaping module. Among them, the beam shaping module is used to adjust the spot size and shape of the light source irradiating the imaging object, or the energy distribution and wavelength range of the spot in the spatial domain, time domain, and frequency domain.

3. The wide-field, wide-bandwidth tilt microscopic imaging defocus correction device according to claim 2, characterized in that, When the light incident module adopts an imaging illumination module, a beam imaging module is added on the basis of the general illumination module. Among them, the beam imaging module is used to perform amplitude or phase patterning modulation on the illumination light after passing through the beam shaping module and image it onto the imaging object.

4. The wide-field, wide-bandwidth tilted microscopic imaging defocus correction device according to claim 1, characterized in that, In the light output module, the beam shaping and imaging module is used to collect the outgoing light from the imaging object, image the imaging object, perform imaging magnification or reduction during imaging, or perform amplitude or phase modulation on the light in the spatial domain, time domain, and frequency domain on the imaging surface or in the imaging optical path.

5. The wide-field, wide-bandwidth tilt microscopic imaging defocus correction device according to claim 1, wherein, In the light output module, the detector is a photoelectric conversion detector and is used to receive and collect the outgoing light from the imaging object collected by the beam shaping and imaging module.

6. The off-focus correction device for wide-field and wide-band tilted microscopic imaging according to claim 1, wherein The image analysis and processing module includes a distortion correction algorithm, and the formula is as follows: ； In the formula, represents the image data of the imaging object directly obtained by the detector or obtained after data processing. The image data is a two-dimensional matrix, which includes the image distortion introduced by the defocus correction module; is the total distortion correction matrix, and the formula is: ； Wherein, is the tilt projection distortion correction matrix, is the tangential stretching distortion correction matrix, and the formula is as follows: ； ； In the formula, is the angle by which the defocus correction module deflects the optical axis of the light incident module or the light output module; represents the dihedral angle formed due to the fact that the meridian plane of the off-axis parabolic mirror does not completely coincide with the light incident surface or the light output surface of the imaging object due to systematic errors.

7. The wide-field, wide-bandwidth tilt microscopic imaging defocus correction device according to claim 1, wherein When an imaging illumination module is adopted, in the light incident module, an incident light path forms a relay imaging surface conjugate to the imaging object surface and a relay imaging surface conjugate to the imaging object surface . The distance from the center of the parabolic surface intercepted by the first off-axis parabolic mirror to this relay imaging surface is the image distance , and satisfy the object-image relationship: ; where is the focal length of the first off-axis parabolic mirror; represents the object distance, which is the distance from the field center on the imaging object to the center of the parabolic surface intercepted by the first off-axis parabolic mirror; the imaging magnification introduced by the first off-axis parabolic mirror is .

8. The wide-field, wide-bandwidth tilted microscopic imaging defocus correction device according to claim 1, wherein In the light emitting module, the outgoing light path forms a relay imaging surface conjugate to the imaging object surface , and the distance from the center of the parabolic surface intercepted by the second off-axis parabolic mirror to it is the image distance , and satisfy the object-image relationship: ; where is the focal length of the second off-axis parabolic mirror; represents the object distance, which is the distance from the field center on the imaging object to the center of the parabolic surface intercepted by the second off-axis parabolic mirror; the imaging magnification introduced by the second off-axis parabolic mirror is .

9. A defocus correction method for wide-field and wide-band tilted microscopic imaging, characterized in that, The wide-field, wide-band tilted microscopic imaging defocus correction device according to any one of claims 1-8 includes: In the light incident module and the light output module, at least the light output module is in a tilted imaging configuration, that is, the optical axis of the imaging optical path is not perpendicular to the imaging object surface. The imaging defocus problem caused by tilted imaging is corrected by the defocus correction module; the image distortion introduced by the defocus correction module is corrected by the image analysis and processing module; finally, a clear and distortion-free imaging effect for the entire field of view and the entire wavelength band of wide field of view and wide wavelength band is achieved.

Images