A snapshot visible light field-infrared spectrum high-resolution imager

Abstract

The present invention relates to the field of optical imaging technology, and specifically provides a snapshot-type visible light field-infrared spectrum high-resolution imager. A target is collimated by a pre-mounted Cassegrain system, then reflected and transmitted through a beam splitter to a visible light field imaging system and an infrared spectrum imaging system, respectively. By organically integrating infrared interference imaging spectroscopy with visible light field imaging technology, a multidimensional data cube of the target can be simultaneously acquired, enabling real-time infrared detection of rapidly changing targets. This avoids the decoupling process of light field and spectrum information, reducing complexity.

Description

Technical Field

[0001] The present invention relates to the technical field of optical imaging, and in particular provides a snapshot type visible light field-infrared spectrum high-resolution imager. Background Art

[0002] Light field spectral imaging technology organically integrates light field imaging technology and spectral imaging technology to achieve full optical information of the target (seven-dimensional light field data ( x , y , z , θ , φ , λ , t ) has broad application in biomedicine, target recognition, particle image velocimetry and environmental monitoring.

[0003] Currently, light field spectral imaging technologies primarily involve multi-angle scanning of the target, using detector arrays to achieve full optical information detection, or incorporating light field imaging structures into imaging spectrometers. These technologies primarily apply to the visible light band. For example, in 2016, Ben-Gurion University in Israel developed a liquid crystal compression hyperspectral imaging system that scans the horizontal plane perpendicular to the system's optical axis, collecting hyperspectral images at equally spaced locations to reconstruct a four-dimensional stereoscopic spectrum of the target. This multi-angle scanning approach results in long scanning times and poor stability, making it incapable of real-time detection of rapidly changing targets. Technologies that achieve full optical information detection using multiple detectors and detector arrays, such as the multispectral light field imaging technology based on a multi-camera array proposed by Nanjing University in 2017, utilize multiple cameras with different bandwidth filters to capture multispectral light field information. However, this approach, based on a detector array, suffers from complex structure, data redundancy, high cost, and difficulty in achieving lightweight design. In 2017, the University of Science and Technology of China proposed a snapshot hyperspectral light field imager that uses two cameras to separately capture portions of the light field. This system consists of a light field camera and a coded aperture snapshot spectral imager (CASSI). These two branches are co-located via a beam splitter and calibrated in spatial, angular, and spectral dimensions. The RGB light field acquired by the light field camera contains the scene's angular information, while the compressed measurements obtained by the CASSI encode the scene's hyperspectral information. The two complement each other to produce a 5D hyperspectral light field with high angular and spectral resolution. While this system achieves snapshot detection of light field spectral imaging information, it lacks the advantages of infrared detection. Technologies that incorporate light field imaging structures into imaging spectrometers, such as the 2018 Harbin Institute of Technology study that incorporated a focused light field imaging structure into a snapshot hyperspectral imaging Fourier transform spectrometer, use a single detector to acquire seven-dimensional optical information of the target. While this technology avoids the problems of the aforementioned two technologies, technical limitations hinder detection in the infrared band. Furthermore, this technology collects multiple dimensions of information on a single detector, making back-end decoupling difficult due to systemic errors.

[0004] Existing solutions use multi-angle scanning of the target to detect its light field information. However, since the detection process requires scanning, its real-time detection is low and its stability cannot be well guaranteed. Technologies that use detector arrays to detect light field information are expensive due to the large number of detectors, and lightweight designs are difficult to achieve. Such systems are sensitive to environmental changes and collect large amounts of data, requiring enormous computational effort during post-processing. The method of introducing light field imaging technology into snapshot spectral imaging technology is limited in its technical principles, primarily operating in the visible light band, and subsequent data processing is relatively complex. Summary of the Invention

[0005] To solve the above problems, the present invention provides a snapshot visible light field-infrared spectrum high-resolution imager. By organically integrating infrared interference imaging spectroscopy technology with visible light field imaging technology, it can simultaneously obtain multi-dimensional data cubes of the target to achieve real-time infrared detection of rapidly changing targets, avoiding the decoupling process of light field information and spectral information, and reducing complexity.

[0006] The present invention provides a snapshot type visible light field-infrared spectrum high-resolution imager, comprising a coaxial reflection collimation system, a beam splitter, a visible light field imaging system and an infrared spectrum imaging system, wherein:

[0007] The coaxial reflective collimation system includes an entrance pupil 1 and a front Cassegrain collimation system;

[0008] The visible light field imaging system includes a light field camera imaging lens, a microlens array and a visible light detector;

[0009] The infrared spectrum imaging system includes an aperture array, a lens array, a lightweight beam splitter and a compensation plate, a high-step multi-level micro-reflector, a low-step multi-level micro-reflector, a relay imaging system, and an infrared detector;

[0010] The target enters the pre-Cassegrain collimation system from the entrance pupil 1, the pre-Cassegrain collimation system performs beam reduction and collimation on the object plane of the target, the beam splitter reflects the visible light of the target to the visible light field imaging system, and transmits the infrared light of the target to the infrared spectrum imaging system, the light field camera imaging lens focuses the visible light reflected by the beam splitter onto the microlens array, and images the light field information of the target onto the visible light detector;

[0011] The aperture array and the lens array converge the transmitted infrared light imaging channels, and image them on the reflective surfaces of the high-step multi-level micro-reflector and the low-step multi-level micro-reflector through the lightweight beam splitter and the compensation plate, and phase modulate the infrared imaging of the target to obtain an infrared interference image array carrying spectral information. The infrared interference image array is coupled to the back focal plane of the infrared detector by the relay imaging system, and the spectral information of the target is reconstructed through the infrared interference image array.

[0012] As a preferred solution, the light field camera imaging lens includes a primary imaging objective lens, a primary image plane, and a light field camera imaging objective lens. The primary imaging objective lens images the target once, and the primary image plane is located within the working distance of the visible light field imaging system. The light field camera imaging objective lens, the microlens array, and the visible light field detector constitute a non-focused visible light field imaging system, which performs light field imaging on the target and images the light field information of the target onto the visible light detector.

[0013] As a preferred solution, the front Cassegrain collimation system adopts a telecentric design, the primary imaging objective lens adopts a telecentric design, the target is imaged at the working distance of the visible light field imaging system, the light field camera imaging objective lens adopts a double telecentric design, the microlens array is placed at the focal plane of the light field camera imaging objective lens, and the detection depth range of the light field imaging part is for:

[0014] (1)

[0015] In the formula is the depth range, is the microlens diameter, is the focal length of the microlens, that is, the distance from the microlens to the primary relay image plane, It is the minimum resolvable size of a single relay image plane.

[0016] As a preferred solution, when the number of pixels of the visible light detector is Q×Q, the number of the microlens array is No × No When the spatial resolution of the light field imaging is Q / No ×Q / No .

[0017] As a preferred solution, the aperture array is placed at the front focal plane of the lens array, and the number of the aperture array is N × N , the lens array is an image-side telecentric system, and the number of the lens array is N × N , the single relay image plane is imaged with multiple aperture channels in a static interferometer system.

[0018] As a preferred solution, the lens array is arranged in a two-dimensional square, each lens unit is square, the duty cycle is 100%, and the size is d l × d l ,like d l = k × d m , then the light field imaging resolution is k × k .

[0019] As a preferred solution, the height of the low-step micro-mirror is , the height of the high-step micro-mirror is The high-step micro-reflector and the low-step micro-reflector are symmetrically placed about the beam splitter, and the high-step micro-reflector and the low-step micro-reflector form Phase modulation unit, each light field imaging unit is phase modulated by the corresponding light field interference image array, which contains the complete three-dimensional spatial distribution information and spectral information of the target, where the spectral sampling point is N 2 The multi-dimensional data cube of the snapshot visible light field-infrared spectrum high-resolution imager is Q / No ×Q / No ×P / No ×P / No × N 2 .

[0020] As a preferred solution, define is the step order of the high-step micro-mirror, is the step order of the low-step micro-mirror, For the High-step micro-mirrors and The phase modulation unit formed by the low-step micro-mirrors, the modulated optical path difference generated by the phase modulation unit .

[0021] As a preferred solution, the relay imaging system couples the infrared interference image array to the rear focal plane of the infrared detector, the relay imaging system adopts an object-space telecentric optical path design, and the relay imaging system adopts an achromatic and athermal design.

[0022] As a preferred solution, all-optical information Detection, depth information z The incident angle of the light Refactoring;

[0023] Establishing a four-dimensional light field of the microlens array and the visible light detector The mathematical matrix transfer model of is the focal plane coordinate of the detector, is the target principal surface coordinate, For the coordinates of the sub-microlenses on the microlens array, the on-axis spatial translation and rotation transformation matrices and the off-axis spatial translation transformation matrix are derived, a microlens light field sampling model is established, the microlens mapping detection area is divided, the geometric correspondence between the target point and the pixel point is determined, and a light field radiation model is established to obtain the image point light intensity of each matrix coordinate.

[0024] The present invention provides a snapshot-type visible light field-infrared spectrum high-resolution imager. The target main surface is collimated by a front Cassegrain system and then reflected and transmitted to a visible light field imaging system and an infrared spectrum imaging system respectively through a beam splitter. The visible light field imaging system includes a light field camera imaging lens and a microlens array. The light field camera imaging objective lens focuses the light reflected from the beam splitter onto the microlens array and images the light field information onto a visible light detector. The infrared spectral imaging system includes an aperture array, a lens array, a lightweight beam splitter, a low-step micro-mirror, and a high-step micro-mirror. The infrared light transmitted by the beam splitter enters the infrared spectral imaging system, passes through the aperture array and the lens array, and is reflected and transmitted by the lightweight beam splitter and the compensation plate respectively, and is imaged on the reflective surfaces of the high-step micro-mirror and the low-step micro-mirror in the form of an image array. Then, it is transmitted and reflected by the lightweight beam splitter respectively, and is imaged onto the infrared detector through the relay imaging system. By organically integrating infrared interferometric imaging spectroscopy technology with visible light field imaging technology, multi-dimensional data cubes of the target can be obtained simultaneously to realize real-time infrared detection of rapidly changing targets, avoiding the decoupling process of light field information and spectral information, and reducing complexity. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 2 is a schematic structural diagram of a snapshot visible light field-infrared spectrum high-resolution imager provided according to an embodiment of the present invention;

[0026] Figure 2 2. It is a schematic diagram of the non-focused light field imaging principle of a snapshot-type visible light field-infrared spectrum high-resolution imager provided according to an embodiment of the present invention;

[0027] Figure 3 1 is a schematic diagram of the optical path of the multiple interference imaging portion of the snapshot visible light field-infrared spectrum high-resolution imager provided by an embodiment of the present invention;

[0028] Figure 4 The present invention is a schematic diagram of a snapshot visible light field-infrared spectrum high-resolution imager provided by an embodiment of the present invention, which reconstructs depth information using a scale-depth space transformation algorithm based on a four-dimensional light field data cube.

[0029] Reference numerals include:

[0030] Entrance pupil 1, front Cassegrain collimation system 2, beam splitter 3, primary imaging objective 4, primary image plane 5, light field camera imaging objective 6, microlens array 7, visible light detector 8, aperture array 9, lens array 10, lightweight beam splitter and compensation plate 11, high-step multi-level micromirror 12, low-step multi-level micromirror 13, relay imaging system 14, infrared detector 15. DETAILED DESCRIPTION

[0031] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In the following description, identical modules are denoted by identical reference numerals. In the case of identical reference numerals, their names and functions are also identical. Therefore, their detailed description will not be repeated.

[0032] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation of the present invention.

[0033] Combine Figure 1 As shown, an embodiment of the present invention provides a snapshot visible light field-infrared spectrum high-resolution imager, including a coaxial reflection collimation system, a beam splitter 3, a visible light field imaging system and an infrared spectrum imaging system, wherein:

[0034] The beam splitter 3 reflects and refracts the visible light band and infrared band of the detection target to the visible light field imaging part and the multiple interference imaging part respectively;

[0035] The coaxial reflective collimation system includes an entrance pupil 1 and a front Cassegrain collimation system 2;

[0036] The visible light field imaging system includes a light field camera imaging lens, a microlens array 7 and a visible light detector 8;

[0037] The infrared spectrum imaging system includes an aperture array 9, a lens array 10, a lightweight beam splitter and compensation plate 11, a high-step multi-level micro-reflector 12, a low-step multi-level micro-reflector 13, a relay imaging system 14, and an infrared detector 15;

[0038] The target enters the pre-Cassegrain collimation system 2 from the entrance pupil 1, and the pre-Cassegrain collimation system 2 performs beam reduction and collimation on the object plane of the target. The beam splitter 3 reflects the visible light of the target to the visible light field imaging system, and transmits the infrared light of the target to the infrared spectrum imaging system. The light field camera imaging lens focuses the visible light reflected by the beam splitter 3 onto the microlens array 7, and images the light field information of the target onto the visible light detector 8.

[0039] The aperture array 9 and the lens array 10 converge the transmitted infrared light imaging channels, and image them on the reflective surfaces of the high-step multi-level micro-reflector 12 and the low-step multi-level micro-reflector 13 through the lightweight beam splitter and the compensation plate 11, and phase modulate the infrared imaging of the target to obtain an infrared interference image array carrying spectral information. The infrared interference image array is coupled to the back focal plane of the infrared detector 15 by the relay imaging system 14, and the spectral information of the target is reconstructed through the infrared interference image array.

[0040] The present invention provides a snapshot-type visible light field-infrared spectrum high-resolution imager. The target main surface is collimated by a front Cassegrain system and then reflected and transmitted to a visible light field imaging system and an infrared spectrum imaging system respectively through a beam splitter 3. The visible light field imaging system includes a light field camera imaging lens and a microlens array 7. The light field camera imaging objective lens 6 focuses the light reflected from the beam splitter onto the microlens array 7 and images the light field information onto a visible light detector 8. The infrared spectral imaging system includes an aperture array 9, a lens array 10, a lightweight beam splitter, a low-step micro-mirror, and a high-step micro-mirror. The infrared light transmitted by the beam splitter enters the infrared spectral imaging system, passes through the aperture array 9 and the lens array 10, and is reflected and transmitted respectively by the lightweight beam splitter and the compensation plate 11, and is imaged on the reflective surfaces of the high-step micro-mirror and the low-step micro-mirror in the form of an image array. Then, it is transmitted and reflected respectively by the lightweight beam splitter, and is imaged onto the infrared detector 15 through the relay imaging system 14. By organically integrating infrared interferometric imaging spectroscopy technology with visible light field imaging technology, multi-dimensional data cubes of the target can be obtained simultaneously to realize real-time infrared detection of rapidly changing targets, avoiding the decoupling process of light field information and spectral information, and reducing complexity.

[0041] In some embodiments, the light field camera imaging lens includes a primary imaging objective lens 4, a primary image plane 5, and a light field camera imaging objective lens 6. The primary imaging objective lens 4 images the target once. The primary image plane 5 is located within the working distance of the visible light field imaging system. The light field camera imaging objective lens 6, the microlens array 7, and the visible light field detector constitute a non-focused visible light field imaging system, which performs light field imaging on the target and images the light field information of the target onto the visible light detector 8.

[0042] In some embodiments, the front Cassegrain collimation system 2 adopts a telecentric design, which ensures the joint detection of the visible light band and the infrared light band through a reflective collimation method. The one-shot imaging objective 4 adopts a telecentric design to image the target at the working distance of the visible light field imaging system. The detection requirements of different distances can be matched by replacing the one-shot imaging objective 44. The light field camera imaging objective 6 adopts a double telecentric design, and the microlens array 7 is placed at the focal plane of the light field camera imaging objective 6. The detection depth range of the light field imaging part is for:

[0043] (1)

[0044] In the formula is the depth range, is the microlens diameter, is the focal length of the microlens, that is, the distance from the microlens to the primary relay image plane, It is the minimum resolvable size of a single relay image plane.

[0045] In some embodiments, when the number of pixels of the visible light detector 8 is Q×Q, the number of the microlens array 7 is No × Not when , the spatial resolution of the light field imaging is Q / No ×Q / No .

[0046] In some embodiments, the aperture array 9 is placed at the front focal plane of the lens array 10, and the number of the aperture array 9 is N × N , the lens array 10 is an image-side telecentric system, and the number of the lens array 10 is N × N , the single relay image plane is imaged with multiple aperture channels in a static interferometer system.

[0047] In some embodiments, the lens array 10 is arranged in a two-dimensional square, each lens unit is square, the duty cycle is 100%, and the size is d l × d l ,like d l = k × d m , then the light field imaging resolution is k × k .

[0048] In some embodiments, the low-step micro-mirror height is , the height of the high-step micro-mirror is The high-step micro-reflector and the low-step micro-reflector are symmetrically placed about the beam splitter, and the high-step micro-reflector and the low-step micro-reflector form Phase modulation unit, each light field imaging unit is phase modulated by the corresponding light field interference image array, which contains the complete three-dimensional spatial distribution information and spectral information of the target, where the spectral sampling point is N 2 The multi-dimensional data cube of the snapshot visible light field-infrared spectrum high-resolution imager is Q / No ×Q / No ×P / No ×P / No × N 2 .

[0049] In some embodiments, defining is the step order of the high-step micro-mirror, is the step order of the low-step micro-mirror, For the High-step micro-mirrors and The phase modulation unit formed by the low-step micro-reflector, the modulated optical path difference generated by the phase modulation unit .

[0050] In some embodiments, the relay imaging system 14 couples the infrared interference image array to the rear focal plane of the infrared detector 15 , the relay imaging system 14 adopts an object-space telecentric optical path design, and the relay imaging system 14 adopts an achromatic and athermal design.

[0051] In some embodiments, the plenoptic information Detection, depth information z The incident angle of the light Refactoring;

[0052] Establishing a four-dimensional light field between the microlens array 7 and the visible light detector 8 The mathematical matrix transfer model of is the focal plane coordinate of the detector, is the target principal surface coordinate, For the coordinates of the sub-microlenses on the microlens array 7, the on-axis spatial translation and rotation transformation matrices and the off-axis spatial translation transformation matrix are derived, a microlens light field sampling model is established, the microlens mapping detection area is divided, the geometric correspondence between the target point and the pixel point is determined, and a light field radiation model is established to obtain the image point light intensity of each matrix coordinate.

[0053] In some embodiments, the light beam splitter and compensation plate 11 split the incident light field into two paths for phase modulation. If the number of detector pixels is P×P, the angular resolution of the light field imaging is P / No ×P / No .

[0054] In some embodiments, The high-step micro-reflectors are placed orthogonally, and the height of the low-step micro-reflectors is , in order to satisfy the principle of complementary optical path difference, the height of the high-step micro-mirror is , the two-step micro-mirrors are placed symmetrically about the beam splitter, and the two-step micro-mirrors form Phase modulation unit, each light field imaging unit is phase modulated by the corresponding light field interference image array, which contains the complete three-dimensional spatial distribution information and spectral information of the target, where the spectral sampling point is N 2 The multi-dimensional data cube of the snapshot visible light field-infrared spectrum high-resolution imager is Q / No ×Q / No ×P / No ×P / No × N 2 .definition is the step order of the high-step micro-mirror, is the step order of the low-step micro-mirror, For the High-step micro-mirrors and The phase modulation unit formed by the low-step micro-mirrors, the modulated optical path difference generated by the phase modulation unit .

[0055] In some embodiments, the relay imaging system 14 couples the interference image array to the rear focal plane of the infrared detector 15 . The relay imaging system 14 adopts an object-space telecentric optical path design, and the relay imaging system 14 adopts an achromatic and athermal design.

[0056] In some embodiments, the plenoptic information Detection, depth information z The incident angle of the light Refactoring.

[0057] Combine Figure 2 As shown, in order to achieve accurate positioning of each pixel and detection of light field intensity, a four-dimensional light field is established between the microlens array 7 and the visible light detector 8. The mathematical matrix transfer model of is the focal plane coordinate of the detector, is the target principal surface coordinate, is the coordinate of the sub-microlens on the microlens array 7. The coaxial space translation, rotation transformation matrix and off-axis space translation transformation matrix are derived, and the microlens light field sampling model is established. The microlens mapping detection area is divided, and the geometric correspondence between the target point and the pixel point can be determined. The light field radiation model is established to obtain the image point light intensity of each matrix coordinate. In order to reconstruct the depth information of the target point, the scale-depth transformation algorithm is used to cube the four-dimensional light field data of the interference channel image unit. Perform deep reconstruction.

[0058] Combine Figure 3 As described above, the figure shows the principle of multiple interference imaging. The problem of optical information crosstalk between spectral channels is solved by the aperture array 9. The target is collimated by the pre-Cassegrain collimator system 2 and the color is separated by the beam splitter 3. After that, it passes through the aperture array 9 and the lens array 10 in sequence to obtain multiple aperture images. The image telecentric design of each interference channel is performed to achieve equal optical path difference modulation of the main light of each field of view. When all optical information is ignored, the target is collimated by the pre-Cassegrain collimator system 2 and the color is separated by the beam splitter 3. After that, it passes through the aperture array 9 and the lens array 10 in sequence to obtain multiple aperture images. When the time resolution of the detector is higher than the change and light blocking and loss are ignored, the full light function is , the light intensity distribution of the light field interference image array is derived as follows:

[0059] (2)

[0060] Where, P is the plenoptic function, is the light propagation angle, is the wavelength, for The sampling optical path difference of the interferometric channel of the coordinate, .

[0061] In some embodiments, the light field interference image intensity distribution can be further expressed as:

[0062] (3)

[0063] In the formula is the target four-dimensional light field data cube, Calculation derivation, The image spectral data cube of the target.

[0064] Combine Figure 4 As shown, the scale-depth space transformation algorithm is used to reconstruct the depth information based on the four-dimensional light field data cube. Intercept or The slice is an extreme plane image EPI. The parallax relationship between the tilt angle of the linear structure in EPI and the sub-image is:

[0065] (4)

[0066] Where, D is the disparity between the uppermost and lowermost sub-images in the sub-image array where the polar plane image is located, Q for y The number of sub-images in the axis direction, p is the pixel size, β is the inclination angle of the linear structure.

[0067] Furthermore, in order to reconstruct the parallax, a scale-depth space with scale-invariant and rotation-invariant properties is constructed by using the ray-Gaussian convolution kernel, and extreme points are found in the space. The ray-Gaussian convolution kernel is

[0068] (5)

[0069] in is the scale parameter of the convolution kernel, is the angle parameter of the convolution kernel.

[0070] In some embodiments, to achieve a denser depth map of the target scene, a light field scale-depth space (Lisad-2) is constructed by the normalized second-order derivative of the ray-Gaussian convolution kernel to achieve parallax reconstruction of non-edge feature rays (Lisad-1 achieves parallax reconstruction of edge feature rays). To achieve spectral reconstruction, the interference sequence composed of the same-name image points of each image unit is extracted as follows:

[0071] (6)

[0072] Where, X For the sub-image array along u The number of sub-images in the axis direction, Q For the sub-image array along v The number of sub-images in the axial direction is 1. The spectrum curve can be reconstructed by Fourier transforming the interference intensity sequence.

[0073] In some embodiments, the visible light field image-infrared spectral image fusion process fuses the visible light field image and the infrared spectral image using the NSCT algorithm. The two images are registered, the infrared spectral image is smoothed and filtered, and the visible light field image and the infrared spectral image are decomposed into high-frequency information and low-frequency information, and then fused using appropriate fusion rules.

[0074] The present invention can achieve the following technical effects:

[0075] 1. The present invention organically integrates visible light field imaging technology with infrared multiple interference spectral imaging technology, overcoming the common problems of existing light field spectral imaging technology based on multi-angle scanning or multiple detectors and detector arrays, such as long scanning time, complex structure, difficult assembly and adjustment, difficulty in lightweighting, and high cost. A snapshot visible light field-infrared spectral imager is proposed, which realizes snapshot detection and information reconstruction of multi-dimensional optical information. It ensures high resolution through the visible light field imaging part while taking into account the advantages of infrared detection.

[0076] 2. The snapshot visible light field-infrared spectrum imager proposed in the present invention adopts a static interference system to improve the stability of interference spectrum information sampling and reduce the volume and weight of the system.

[0077] 3. The snapshot visible light field-infrared spectrum imager proposed in the present invention has a spectral detection band that covers the entire infrared band, reflects the thermal radiation characteristics of the target, is less affected by the environment, is easy to detect and identify hidden targets, and the characteristic peaks of the infrared band are densely distributed, and has a wide range of applications.

[0078] 4. The snapshot visible light field-infrared spectrum imager proposed in the present invention can obtain a light field interference image array. Through deep reconstruction and atlas data processing combined with visible light field and infrared spectrum image fusion technology, three-dimensional stereo atlas data information of the target can be obtained.

[0079] 5. The snapshot visible light field-infrared spectrum imager proposed in the present invention is connected through a beam splitter and can be designed independently. In addition, the design difficulty, processing difficulty and assembly difficulty are greatly reduced when the processing accuracy is required.

[0080] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0081] The above specific embodiments of the present invention do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made based on the technical concept of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A snapshot visible light field-infrared spectrum high-resolution imager, characterized in that: It includes a coaxial reflection collimation system, a beam splitter, a visible light field imaging system and an infrared spectrum imaging system, among which: The coaxial reflective collimation system includes an entrance pupil and a front Cassegrain collimation system; The visible light field imaging system includes a light field camera imaging lens, a microlens array and a visible light detector; The infrared spectrum imaging system includes an aperture array, a lens array, a lightweight beam splitter and a compensation plate, a high-step multi-level micro-reflector, a low-step multi-level micro-reflector, a relay imaging system, and an infrared detector; The target enters the pre-Cassegrain collimation system from the entrance pupil, the pre-Cassegrain collimation system performs beam reduction and collimation on the object plane of the target, the beam splitter reflects the visible light of the target to the visible light field imaging system, and transmits the infrared light of the target to the infrared spectrum imaging system, the light field camera imaging lens focuses the visible light reflected by the beam splitter onto the microlens array, and images the light field information of the target onto the visible light detector; The aperture array and the lens array converge the transmitted infrared light imaging channels, and image them on the reflective surfaces of the high-step multi-level micro-reflector and the low-step multi-level micro-reflector through the lightweight beam splitter and the compensation plate, and phase modulate the infrared imaging of the target to obtain an infrared interference image array carrying spectral information. The infrared interference image array is coupled to the back focal plane of the infrared detector by the relay imaging system, and the spectral information of the target is reconstructed through the infrared interference image array.

2. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1, characterized in that: The light field camera imaging lens includes a primary imaging objective lens, a primary image plane, and a light field camera imaging objective lens. The primary imaging objective lens performs a primary image on the target. The primary image plane is located within the working distance of the visible light field imaging system. The light field camera imaging objective lens, the microlens array, and the visible light field detector constitute a non-focused visible light field imaging system, which performs light field imaging on the target and images the light field information of the target onto the visible light detector.

3. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 2, characterized in that: The front Cassegrain collimation system adopts a telecentric design, the primary imaging objective lens adopts a telecentric design, and the target is imaged at the working distance of the visible light field imaging system. The light field camera imaging objective lens adopts a double telecentric design, and the microlens array is placed at the focal plane of the light field camera imaging objective lens. The detection depth range of the light field imaging part is for: (1) In the formula is the depth range, is the microlens diameter, is the focal length of the microlens, that is, the distance from the microlens to the primary relay image plane, It is the minimum resolvable size of a single relay image plane.

4. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 3, characterized in that: When the number of pixels of the visible light detector is Q×Q, the number of the microlens array is Ne × Ne , the spatial resolution of the light field imaging is Q / Ne ×Q / Ne .

5. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1, characterized in that: The aperture array is placed at the front focal plane of the lens array, and the number of the aperture array is N × N , the lens array is an image-side telecentric system, and the number of the lens array is N × N , the single relay image plane is imaged with multiple aperture channels in a static interferometer system.

6. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1 or 5, characterized in that: The lens array is arranged in a two-dimensional square, each lens unit is square, the duty cycle is 100%, and the size is d l × d l ,like d l = k × d m , then the light field imaging resolution is k × k .

7. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1 or 5, characterized in that: The height of the low-step micro-mirror is , the height of the high-step micro-mirror is The high-step micro-reflector and the low-step micro-reflector are symmetrically placed about the beam splitter, and the high-step micro-reflector and the low-step micro-reflector form Phase modulation unit, each light field imaging unit is phase modulated by the corresponding light field interference image array, which contains the complete three-dimensional spatial distribution information and spectral information of the target, where the spectral sampling point is N 2 The multi-dimensional data cube of the snapshot visible light field-infrared spectrum high-resolution imager is Q / Ne ×Q / Ne ×P / Ne ×P / Ne × N 2 .

8. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1 or 5, characterized in that: definition is the step order of the high-step micro-mirror, is the step order of the low-step micro-mirror, For the High-step micro-mirrors and The phase modulation unit formed by the low-step micro-reflector, the modulated optical path difference generated by the phase modulation unit .

9. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1 or 5, characterized in that: The relay imaging system couples the infrared interference image array to the rear focal plane of the infrared detector. The relay imaging system adopts an object-space telecentric optical path design and an achromatic and athermal design.

10. The snapshot visible light field-infrared spectrum high-resolution imager according to claim 1, characterized in that: All-optical information Detection, depth information z By the angle of incidence of light Refactoring; Establishing a four-dimensional light field of the microlens array and the visible light detector The mathematical matrix transfer model of is the focal plane coordinate of the detector, is the target principal surface coordinate, For the coordinates of the sub-microlenses on the microlens array, the on-axis spatial translation and rotation transformation matrices and the off-axis spatial translation transformation matrix are derived, a microlens light field sampling model is established, the microlens mapping detection area is divided, the geometric correspondence between the target point and the pixel point is determined, and a light field radiation model is established to obtain the image point light intensity of each matrix coordinate.

Images