Gaze five-dimensional hyperspectral polarimetric depth imaging system

Abstract

This invention discloses a staring five-dimensional hyperspectral polarization depth imaging system, comprising a projector, a first imaging lens, a first polarizer, a second imaging lens, a collimating lens, a beam splitter, a tunable filter, a second polarizer, a focusing lens, a first camera, a third imaging lens, a polarization camera, and a computer. The projector, first imaging lens, and first polarizer are connected sequentially; the second imaging lens, collimating lens, and beam splitter are connected sequentially; the tunable filter, second polarizer, focusing lens, and first camera are connected sequentially; and the computer is connected to the projector, first camera, polarization camera, and tunable filter. This invention organically integrates hyperspectral imaging, three-dimensional imaging, and polarization imaging technologies to form an integrated five-dimensional hyperspectral polarization depth imaging system. It features high depth resolution, fast scanning speed, high data fusion accuracy, and small size for portability, making it valuable for applications in industrial scratch detection, precision agriculture, and other fields.

Description

Technical Field

[0001] This invention belongs to the field of optical technology, specifically relating to a staring five-dimensional hyperspectral polarization depth imaging system. Background Technology

[0002] Currently, imaging spectrometers, based on multi-channel spectral technology, integrate optical imaging and spectral measurement, simultaneously acquiring image information and corresponding spectral information of a target. Imaging spectrometers can analyze, measure, and process the structure and composition of substances, offering advantages such as high analytical accuracy and a wide measurement range. They are widely used in fields such as petroleum, materials science, agronomy, geological exploration, biochemistry, medicine and health, environmental protection, and safety monitoring. However, traditional hyperspectral imaging techniques can only acquire the spectral information of the object under test, failing to obtain its three-dimensional morphological information. For objects with both morphological and chromatic characteristics, they cannot reconstruct their true information. Current 3D reconstruction techniques mainly include time-of-flight methods, binocular stereo vision based on triangulation, and structured light 3D measurement. However, traditional 3D reconstruction techniques cannot acquire the spectral and polarization information of objects. Compared with common visible light, remote sensing, and infrared imaging, polarization imaging can acquire multi-dimensional polarization information of objects, which has a significant and unique advantage in the field of image vision. Using the acquired polarization information, the detailed features of the measured object can be greatly enhanced. For example, some defects are difficult to distinguish with ordinary area array cameras, but can be differentiated using polarization information. Achieving integrated acquisition of the three-dimensional shape, spectral information, and polarization information of the object under test is a challenge in existing technologies. Summary of the Invention

[0003] In order to overcome the shortcomings of the prior art, the purpose of this invention is to provide a staring five-dimensional hyperspectral polarization depth imaging system.

[0004] A staring five-dimensional hyperspectral polarization depth imaging system includes a projector, a first imaging lens, a first polarizer, a second imaging lens, a collimating lens, a beam splitter, a tunable filter, a second polarizer, a focusing lens, a first camera, a third imaging lens, a polarizing camera, and a computer. The projector, first imaging lens, and first polarizer are connected in sequence; the second imaging lens, collimating lens, and beam splitter are connected in sequence; the tunable filter, second polarizer, focusing lens, and first camera are connected in sequence; and the computer is connected to the projector, first camera, polarizing camera, and tunable filter.

[0005] The projector projects structured light grating stripes onto the surface of the sample to be tested, and the depth undulations of the sample surface modulate the structured light pattern.

[0006] The second imaging lens images the object under test onto the focal plane of the collimating lens, and the collimating lens collimates the reflected light image into parallel light at different angles to extend the back-end optical path.

[0007] The beam splitter splits the signal light into two, and maintains a one-to-one correspondence between the image planes of the two signal lights in space.

[0008] The tunable filter achieves spectral scanning by continuously changing the transmission band.

[0009] The aforementioned staring five-dimensional hyperspectral polarization depth imaging system uses a single signal beam that passes through a tunable filter, a second polarizer, and a focusing lens before reaching the photosensitive surface of a first camera to form a grayscale image of the sample under test. By rotating the angle of the second polarizer, specular reflections from the surface of the object under test are filtered out, resulting in a more uniform diffuse reflection image of the object's surface, thereby improving the resolution of the three-dimensional reconstruction.

[0010] In the aforementioned staring five-dimensional hyperspectral polarization depth imaging system, another signal light passes through a third imaging lens and is focused onto a polarization camera to form a polarization image.

[0011] The four-dimensional hyperspectral depth data obtained by the first camera and the polarization image data obtained by the polarization camera are in one-to-one correspondence based on spatial conjugation.

[0012] The beneficial effects of this invention are:

[0013] This invention overcomes the shortcomings of existing equipment, such as inability to achieve high-dimensional imaging, limited data, and fragmented equipment. It organically integrates hyperspectral imaging, three-dimensional imaging, and polarization imaging technologies to form an integrated five-dimensional hyperspectral polarization depth imaging system. The system possesses a series of excellent characteristics, including high depth resolution (30.7 micrometers), fast scanning speed, high data fusion accuracy, and small size and portability, making it of significant application value in fields such as industrial scratch detection and precision agriculture. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of a staring five-dimensional hyperspectral polarization depth imaging system.

[0015] Figure 1 In the diagram, there are: 1. Projector; 2. First imaging lens; 3. First polarizer; 4. Second imaging lens; 5. Collimating lens; 6. Beam splitter; 7. Tunable filter; 8. Second polarizer; 9. Focusing lens; 10. First camera; 11. Third imaging lens; 12. Polarizing camera; and 13. Computer.

[0016] Figure 2 This is a 5D image of the craft cart obtained by the staring five-dimensional hyperspectral polarization depth imaging system.

[0017] Figure 3 This is a 5D image of a leaf obtained by a staring five-dimensional hyperspectral polarization depth imaging system. Detailed Implementation

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

[0019] like Figure 1 As shown, a staring five-dimensional hyperspectral polarization depth imaging system includes a projector 1, a first imaging lens 2, a first polarizer 3, a second imaging lens 4, a collimating lens 5, a beam splitter 6, a tunable filter 7, a second polarizer 8, a focusing lens 9, a first camera 10, a third imaging lens 11, a polarizing camera 12, and a computer 13. The computer 13 is connected to the projector 1, the first camera 10, the polarizing camera 12, and the tunable filter 7.

[0020] The natural light generated by the projector 1 is converted into linearly polarized light after passing through the first imaging lens 2 and the first polarizer 3. After being reflected by the surface of the object to be measured, the physical properties of the surface of the object to be measured, such as the structure, material, and incident angle of the light itself, will change the polarization state and spectrum.

[0021] Therefore, projector 1 projects structured light grating fringes onto the surface of the sample under test, and the depth undulations of the sample surface modulate the structured light pattern. The reflected light passes through the second imaging lens 4 and the collimating lens 5 before reaching the beam splitter 6. The second imaging lens 4 images the object under test at the focal plane of the collimating lens 5, and the collimating lens 5 collimates the reflected light image into parallel light at different angles to extend the optical path at the rear end.

[0022] Beam splitter 6 splits the signal light into two, and maintains a one-to-one correspondence between the image planes of the two signal lights in space.

[0023] One signal beam passes through a tunable filter 7, a second polarizer 8, and a focusing lens 9 before reaching the photosensitive surface of the first camera 10 to form a grayscale image of the sample under test. The computer 13 then performs three-dimensional reconstruction based on the image sequence. The tunable filter 7 achieves spectral scanning by continuously changing the transmission band.

[0024] In this method, the polarization angle of the specular reflected light from the surface of the object under test is consistent with the angle of the first polarizer. The rotation angle of the first polarizer is parallel to the rotation angle of the second polarizer. The specular reflected light from the surface of the object under test is filtered out by the second polarizer, thereby obtaining a more uniform diffuse reflection image of the surface of the object under test, which improves the resolution of the 3D reconstruction.

[0025] The other signal light passes through the third imaging lens 11 and is focused onto the polarization camera 12 to form a polarization image. The four-dimensional hyperspectral depth data and the polarization image data are in one-to-one correspondence based on spatial conjugation.

[0026] Application Examples

[0027] The 5D imaging results of the craft cart by the staring five-dimensional hyperspectral polarization depth imaging system are as follows: Figure 2 As shown, the 5D dataset displays the optical and polarization characteristics of the craft cart from different viewing angles. The three-dimensional morphology and spectral polarization characteristics of scratches and defects on the cart can be observed. This has significant application value for industrial defect detection.

[0028] The results of 5D imaging of leaves by the staring five-dimensional hyperspectral polarization depth imaging system are as follows: Figure 3 As shown, the 5D dataset demonstrates the optical and polarization properties of leaves from different viewing angles. Yellowing and pests / diseases in the plants are clearly distinguishable in the images, indicating the system's significant application value in precision agriculture.

[0029] The embodiments described above can be further combined or replaced, and these embodiments are merely descriptions of preferred embodiments of the present invention, not limitations on the concept and scope of the present invention. Various changes and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the inventive concept are all within the protection scope of the present invention. The protection scope of the present invention is given by the appended claims and any equivalents.

Claims

1. A staring five-dimensional hyperspectral polarization depth imaging system, characterized in that, The system includes a projector (1), a first imaging lens (2), a first polarizer (3), a second imaging lens (4), a collimating lens (5), a beam splitter (6), a tunable filter (7), a second polarizer (8), a focusing lens (9), a first camera (10), a third imaging lens (11), a polarizing camera (12), and a computer (13). Among these components, the projector (1), the first imaging lens (2), and the first polarizer (3) are connected in sequence; the second imaging lens (4), the collimating lens (5), and the beam splitter (6) are connected in sequence; the tunable filter (7), the second polarizer (8), the focusing lens (9), and the first camera (10) are connected in sequence; and the computer (13) is connected to the projector (1), the first camera (10), the polarizing camera (12), and the tunable filter (7) respectively. The projector (1) projects structured light grating stripes onto the surface of the sample to be tested, and the depth undulation of the sample surface modulates the structured light pattern. The second imaging lens (4) images the object to be tested at the focal plane of the collimating lens (5). The collimating lens (5) collimates the reflected light image into parallel light at different angles to extend the rear optical path. The beam splitter (6) splits the signal light into two and keeps the image planes of the two signal lights in a one-to-one correspondence in space. The tunable filter (7) achieves spectral scanning by continuously changing the transmission band; One signal light passes through a tunable filter (7), a second polarizer (8), and a focusing lens (9) to the photosensitive surface of the first camera (10) to form a grayscale image of the sample to be tested. By rotating the angle of the second polarizer (8), the specular reflection light on the surface of the object to be tested is filtered out, thereby obtaining a more uniform diffuse reflection image of the surface of the object to be tested, thereby improving the resolution of the three-dimensional reconstruction. Another signal light passes through the third imaging lens (11) and is focused on the polarization camera (12) to form a polarization image; The four-dimensional hyperspectral depth data obtained by the first camera (10) and the polarization image data obtained by the polarization camera (12) are in one-to-one correspondence according to the spatial conjugate relationship.

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