Polarization Hyperspectral Imaging Device Based on Micro-Nano Fabry-Perot Resonator

Abstract

The present invention belongs to the technical field of hyperspectral polarization imaging, and specifically discloses a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator, which includes: a first optical mirror group, an electrically controlled polarization analyzer module, a micro-nano Fabry-Perot resonator array, a second optical mirror group, and a detector, which are sequentially arranged along the incident light direction, and a data acquisition control and processing system; the first optical mirror group is used to collect the light emitted by a two-dimensional space target as incident light; the electrically controlled polarization analyzer module is used to analyze the incompletely polarized light into linearly polarized light in different polarization analysis directions; the micro-nano Fabry-Perot resonator array is used to obtain the spectra of multiple bands of the linearly polarized light in each direction; the second optical mirror group is used to converge the spectra of each band to the detector respectively; the present invention can achieve the high-speed, high-resolution and high-precision acquisition of frame-type polarization hyperspectral image information.

Description

Technical Field

[0001] The present invention belongs to the field of optical remote sensing detection technology, and particularly relates to a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator. Background Art

[0002] The electromagnetic waves radiated by an object contain important remote sensing information such as the space, spectrum, and polarization of the target. It can not only be used to invert the morphological and physical-chemical characteristics of the target, but also remove background noise to provide information such as high-contrast surfaces, topographies, shadows, and roughness. In order to make the three-dimensional information of space, spectrum, and polarization complement each other and enhance the ability to detect targets in complex backgrounds, a new type of cutting-edge remote sensing detection technology that integrates three-dimensional information acquisition skills has emerged: polarization spectral imaging technology.

[0003] Polarization hyperspectral imaging technology is a new type of optoelectronic imaging detection technology that combines spectral measurement, polarization measurement, and imaging technology. It can simultaneously obtain three intrinsic information such as the intensity information, spectral information, and polarization information of the reflected light of the target. This technology can invert the intensity characteristics and polarization characteristics of the target in different spectral bands, greatly improving the ability of light to describe the intrinsic information of the target, and making target detection and recognition more accurate.

[0004] Polarization hyperspectral imaging technology is formed by the fusion of polarization imaging technology and hyperspectral spectroscopy technology. The characteristics of the latter two determine the characteristics of the former. Existing polarization imaging technologies are usually realized by adjusting a polarization analyzer, aperture division polarization imaging, amplitude division polarization imaging, spectroscopic polarization imaging, or pixel division polarization imaging. Existing hyperspectral imaging technologies usually use different spectral processing mechanisms to obtain hyperspectral images of a two-dimensional scene. Common spectral processing mechanisms are, for example, dispersive spectral processing mechanisms, interferometric spectral processing mechanisms, and filter-based spectral processing mechanisms.

[0005] The dispersive spectral processing mechanism is based on a slit and a dispersive element, and uses a push-broom method to obtain the spectral image of a two-dimensional scene. As a whole, there are deficiencies that the spectral resolution and light flux are restricted by the slit, and the acquisition of two-dimensional scene image information requires push-broom.

[0006] The interferometric spectral processing mechanism splits light through an interferometer and obtains spectral information after performing a Fourier transform on the interference result. As a whole, there are deficiencies that most of the internal parts of the interferometer need moving components to generate interference, the seismic resistance is poor, and the acquisition of two-dimensional scene image information also requires push-broom.

[0007] The filter-based spectral processing mechanism realizes spectral separation through a filter. As a whole, there is a deficiency that a single filter can only obtain the two-dimensional scene image information of a single spectral band, and full-spectrum imaging needs to be obtained by switching filters time-division.

[0008] Overall, for the polarization hyperspectral imaging device built using the existing technology, there are mutual constraints among the structure, spectral acquisition speed, polarization imaging accuracy, spectral coverage range, and spectral resolution. It is very difficult to optimize the indicators of structure, polarization imaging accuracy, spectral coverage range, and spectral resolution simultaneously. Summary of the Invention

[0009] The object of the present invention is to provide a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator to solve the deficiencies in the existing technology.

[0010] The technical solution adopted by the present invention is as follows:

[0011] A polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator includes:

[0012] A first optical mirror group, an electro-controlled polarization analyzer module, a micro-nano Fabry-Perot resonator array, a second optical mirror group, and a detector arranged in sequence along the incident light direction, and a data acquisition control and processing system;

[0013] The first optical mirror group is used to collect the light emitted by the two-dimensional space target as the incident light, where the incident light is incompletely polarized light; the electro-controlled polarization analyzer module is used to analyze the incompletely polarized light into linearly polarized lights with different polarization analysis directions; the micro-nano Fabry-Perot resonator array is used to obtain the spectra of multiple bands of the linearly polarized light in each direction; the second optical mirror group is used to converge the spectra of each band to the detector respectively; the data acquisition control and processing system is used to control the electro-controlled polarization analyzer module to obtain different polarization analysis directions, and control the detector to snapshot the to-be-detected spectra to obtain the hyperspectral data cube in each polarization direction, and process the hyperspectral data cube.

[0014] For the polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, preferably, the first optical mirror group includes one of a telescopic objective lens, a microscopic objective lens, and a common objective lens.

[0015] For the polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, preferably, the electro-controlled polarization analyzer module includes a first polarizer and a first motor; the first motor controls the rotation of the first polarizer to obtain polarizers with different polarization analysis directions; the input end of the first motor is connected to the output end of the data acquisition control and processing system.

[0016] For the polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, preferably, the first polarizer is a broadband high extinction ratio polarizer.

[0017] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the first motor is a high-speed and high-precision stepper motor.

[0018] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the electrically controlled polarization analyzer module further includes a depolarizer; the depolarizer is arranged along the direction of the incident light and is disposed between the first polarizer and the micro-nano Fabry-Perot resonator array.

[0019] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the micro-nano Fabry-Perot resonator array includes a plurality of Fabry-Perot resonator units; the distances between two oppositely arranged reflectors of each Fabry-Perot resonator unit are different.

[0020] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the second optical mirror group is a microlens array; the microlens array is arranged in one-to-one correspondence with the micro-nano Fabry-Perot resonator array.

[0021] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the detector is an SCMOS sensor.

[0022] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the different polarization analysis directions include a 0° polarization analysis direction, a 60° polarization analysis direction, and a 120° polarization analysis direction.

[0023] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the polarization hyperspectral imaging device further includes: a first band-pass filter arranged along the direction of the incident light; the first band-pass filter is disposed on a side of the first optical mirror group away from the electrically controlled polarization analyzer module.

[0024] The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator as described above, wherein preferably, the first band-pass filter includes a high-pass filter and a near-infrared filter.

[0025] Compared with the prior art, in the present invention, light emitted by a two-dimensional space target is collected by means of an optical lens group as incident light, and the incident light is polarization-analyzed by an electrically controlled polarization analyzer module into linearly polarized light with different polarization directions. For each direction of linearly polarized light, a spectrum of multiple bands of the linearly polarized light is obtained by means of a micro-nano Fabry-Perot resonator array. Then, the spectra of multiple bands of the linearly polarized light are converged, detected, and processed, so as to obtain a hyperspectral Stokes parameter data cube (English name: Stokes Parameters, including S0, S1, S2) and a hyperspectral degree of linear polarization data cube (English name: Degree of Line Polarization, abbreviated as: DoLP) of the two-dimensional space target, thereby achieving high-speed, high-resolution, and high-precision acquisition of frame-type polarization hyperspectral image information. Description of the Drawings

[0026] Figure 1 is a schematic diagram of the principle of a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator provided by the present application;

[0027] Figure 2 is a physical diagram of a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator provided by the present application;

[0028] Figure 3 is a schematic diagram of the principle of a Fabry-Perot resonator unit;

[0029] Figure 4 is a simplified diagram of collecting polarization information of different bands by pixels when the polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator provided by the present application is in use;

[0030] Figure 5 is a simplified diagram of the single-pixel single-band imaging process when the polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator provided by the present application is in use;

[0031] Figure 6 is a schematic diagram of the process of the data acquisition control and processing system processing hyperspectral data cubes in polarization directions of 0°, 60°, and 120°;

[0032] Figure 7 are the processed Stokes parameter data of each band (taking the S0 parameter as an example);

[0033] Figure 8 are the processed DoLP parameter data of each band. Detailed Embodiments

[0034] The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as a limitation to the present invention.

[0035] An embodiment of the present invention provides a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator, such as Figure 1 shown. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator includes: a first optical mirror group, an electrically controlled polarization analyzer module, a micro-nano Fabry-Perot resonator array, a second optical mirror group, and a detector, which are sequentially arranged along the incident light direction, and a data acquisition control and processing system.

[0036] The first optical mirror group is used to collect the light emitted by the two-dimensional space target as incident light, wherein the incident light is incompletely polarized light; the electrically controlled polarization analyzer module is used to analyze the incompletely polarized light into linearly polarized lights with different polarization analysis directions; the micro-nano Fabry-Perot resonator array is used to obtain the spectra of multiple bands of the linearly polarized light in each direction; the second optical mirror group is used to converge the spectra of each band to the detector; the data acquisition control and processing system is used to control the electrically controlled polarization analyzer module to obtain different polarization analysis directions, and control the detector to snapshot the spectrum to be detected to obtain the hyperspectral data cube in each polarization direction, and process the hyperspectral data cube.

[0037] In this application, the light emitted by the two-dimensional space target is collected as incident light by means of an optical mirror group, and the incident light is analyzed into linearly polarized lights with different polarization analysis directions by an electrically controlled polarization analyzer module. For the linearly polarized light in each direction, the spectra of multiple bands of the linearly polarized light are obtained by means of a micro-nano Fabry-Perot resonator array. Then, the spectra of multiple bands of the linearly polarized light are converged, detected, and processed, so as to obtain the hyperspectral Stokes parameter data cube (English name: Stokes Parameters, including S0, S1, S2) and the hyperspectral degree of linear polarization data cube (English name: Degree of Line Polarization, abbreviated as: DoLP) of the two-dimensional space target, thereby realizing the high-speed, high-resolution, and high-precision acquisition of frame-type polarization hyperspectral image information.

[0038] In specific implementation, the units of the first optical lens group, the electro-control polarization analyzer module, the micro-nano Fabry-Perot resonator array, the second optical lens group, the detector, and the data acquisition control and processing system described above are carefully designed by the applicant around the data acquisition effect of high spatial resolution, high spectral resolution, and high polarization measurement accuracy, as well as the miniaturization of the entire device. This is also the difficulty in the optical system design of a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator such as this application. A well-performing optical system can achieve the preset effect only through the coordinated operation of an organic whole. It is a design workload that involves the whole body when improving a certain component, rather than a simple superposition of the optical components of the system. This is the basis but also the difficult point of the optical system. Therefore Figure 2 Provide a physical diagram of a polarization hyperspectral imaging device based on a micro-nano Fabry-Perot resonator of this application to achieve the preset effect of this application in cooperation with the physical object.

[0039] Please further refer to Figure 2 As shown, in this application, the first optical lens group includes one of a telescopic objective lens, a microscopic objective lens, and a common objective lens. Telescopic objective lenses, microscopic objective lenses, and common objective lenses, as observation tools for two-dimensional space targets, have strong practicability. In this application, considering the application scenario of remote sensing detection, a telescopic objective lens is preferably used in this application. At the same time, considering the integration and small-size requirements of the device, a Nikon-F bayonet lens is used as the objective lens of the telescope.

[0040] Furthermore, if only a telescopic objective lens is used to capture the light (i.e., incident light) emitted by a two-dimensional space target, the incident light obtained at this time is polychromatic incompletely polarized light, which includes various bands in nature. Therefore, in specific implementation, a first band-pass filter (i.e., Figure 2 the band-pass filter) needs to be added to the objective lens of the telescope, so that the incident light captured by the telescope is polychromatic incompletely polarized light in a specified wide band. That is, the polarization hyperspectral imaging device further includes: a first band-pass filter (i.e., Figure 2 the band-pass filter) arranged along the incident light direction; the first band-pass filter is arranged on the side of the first optical lens group away from the electro-control polarization analyzer module. In specific implementation, the first band-pass filter can be realized by a combination of a high-pass filter and a near-infrared filter.

[0041] In addition, the electro-control polarization analyzer module of this application is used to analyze the incompletely polarized light into linearly polarized light in different polarization analysis directions. Therefore, it is set that the electro-control polarization analyzer module includes a first polarizer (i.e., Figure 2 the broadband high extinction ratio polarizer) and a first motor (i.e., Figure 2a high-speed and high-precision stepping motor); the first motor controls the rotation of the first polarizer to obtain polarizers with different polarization analysis directions; the input end of the first motor is connected to the data acquisition control and processing system (corresponding to Figure 2 the control acquisition unit and the data processing system. The input end of the first motor is connected to the output end of the control acquisition unit).

[0042] In specific implementation, the first polarizer is a broadband high-extinction-ratio polarizer. The broadband high-extinction-ratio polarizer performs polarization analysis on the incident light that has passed through the first optical lens group, specifically, after passing through a high-pass filter, a near-infrared filter, and the objective lens of a telescope, and changes the complex-color incompletely polarized light emitted from the objective lens into linearly polarized light. Among them: the direction of the linearly polarized light is related to the bias direction of the first polarizer, that is, the broadband high-extinction-ratio polarizer. In this embodiment, the polarization direction of the broadband high-extinction-ratio polarizer is controlled by the first motor (that is, Figure 2 a high-speed and high-precision stepping motor), and the first motor (that is, Figure 2 a high-speed and high-precision stepping motor) controls the rotation of the first polarizer to obtain different polarization analysis directions of 0°, 60°, and 120°; to achieve the balance between the rotation of the first polarizer and the sampling time, the first motor in this embodiment needs to use a high-speed and high-precision stepping motor.

[0043] In addition, during the construction, testing, and use of this application system, through a large number of experiments, it is found that if the linearly polarized light emitted from the first polarizer is not processed and directly enters the micro-nano Fabry-Perot resonator array, the linearly polarized light will change its polarization state within the micro-nano Fabry-Perot resonator array under the action of each micro-nano Fabry-Perot resonator in the micro-nano Fabry-Perot resonator array, and then there will be a situation where there is a large amount of random noise in the micro-nano Fabry-Perot resonator. To overcome this phenomenon, this application uniquely sets a depolarizer between the first polarizer and the micro-nano Fabry-Perot resonator array, that is, the electro-controlled polarization analysis module further includes a depolarizer; the depolarizer is arranged along the direction of the incident light and is arranged between the first polarizer and the micro-nano Fabry-Perot resonator array. The depolarizer changes the linearly polarized light into pseudo-randomly polarized incompletely polarized light, retains the amplitude information of the incident linearly polarized light, and does not generate random noise in the F-P resonator.

[0044] And the micro-nano Fabry-Perot resonator array of this application for obtaining the spectra of multiple bands of the linearly polarized light in each direction is a filter component array composed of Fabry-Perot resonators (that is, Fabry-Perot resonator units, or F-P resonators) with different transmission spectra. The number of F-P resonators set determines the number of bands. Exemplarily, such as Figure 4As shown, the micro-nano Fabry-Perot resonator array of this embodiment is composed of 5×5 F-P resonators with different transmission spectra. Therefore, spectral information of 25 bands can be collected in the 5×5 pixel area.

[0045] Furthermore, referring to Figure 3 As shown, each F-P resonator is a multi-beam interferometer composed of two parallel reflecting elements (including but not limited to glass plates), and the inner surfaces of the two reflecting elements facing each other have high reflectivity. When the frequency of the incident light satisfies its resonance condition, a very high peak will appear in its transmission spectrum, corresponding to a very high transmittance. As Figure 3 As shown, by adjusting the distance L between the two glass plates, modulation of light with different wavelengths is achieved. Its spectral separation formula is:

[0046] kλ = 2nLcosθ

[0047] In the formula, k is the harmonic order, n is the reflectivity of the inner wall of the resonator, θ is the exit angle, and L is the distance between the two reflecting elements of the resonator.

[0048] When n, θ, and L are fixed, the incident polychromatic light undergoes multiple reflections in the cavity to generate interference, thereby achieving the transmission of a specific wavelength λ. In the micro-nano F-P resonator array, each F-P resonator realizes the transmission of different wavelengths by controlling the internal distance L. During the wavelength selection process, the F-P resonator generates multiple-order harmonics, and the first-order and second-order harmonics have strong energy, and there is a certain interval between the peak wavelengths of the first-order and second-order harmonics. In order to suppress the interference between harmonics within a certain spectral range, a band-pass filter composed of a visible light high-pass filter and a near-infrared low-pass filter is used to suppress harmonic interference before the light enters the F-P resonator. The spectrally selected light is converged to the detector through the second optical mirror group.

[0049] Among them, the second optical mirror group is a micro-lens array, and the micro-lens array is arranged corresponding to the micro-nano Fabry-Perot resonator array one by one. At the same time, the micro-lens array converges the spectral energy to the detector, and the detector is selected on the surface of the SCMOS imaging sensor. Therefore, the spectrally selected light converges the energy to the surface of the SCMOS imaging sensor through the micro-lens array. Compared with an ordinary CMOS imaging sensor, the SCMOS imaging sensor has characteristics such as high quantum efficiency and low readout noise; compared with a CCD imaging sensor, the SCMOS imaging sensor has characteristics such as low power consumption, small size, and simple structure. Therefore, during the acquisition of polarization hyperspectral information, the energy decays more after the light passes through the polarization and spectral separation modules. Using an SCMOS imaging sensor with high quantum efficiency and low readout noise can achieve weak signal detection.

[0050] In specific implementation, for the data acquisition control and processing system, on the one hand, it controls the detector to snapshot the to-be-detected spectrum to obtain the hyperspectral data cube in each polarization direction (i.e., Figure 2 's control acquisition unit), specifically by controlling the spectral snapshot of the SCMOS imaging sensor. On the other hand, it controls the electro-optic polarization modulation module to obtain different polarization modulation directions, specifically by controlling the above-mentioned broadband high-extinction-ratio polarizer to obtain polarizers in different directions (i.e., Figure 2 's control acquisition unit). In this embodiment, after completing the acquisition of the information in one polarization direction, the high-speed and high-precision stepping motor (i.e., the first motor) quickly switches the polarizer (i.e., the broadband high-extinction-ratio polarizer) to the next angle (about 50 ms), and completes the acquisition of the information in three polarization angles (in the case of a single-image integration time of 15 ms, it takes about 200 ms to complete the acquisition of hyperspectral data in three polarization angles, and 5 groups of polarization hyperspectral image data can be acquired per minute); on the other hand, it processes the hyperspectral data cubes in the polarization directions of 0°, 60°, and 120° (i.e., Figure 2 's data processing system). As shown in Figure 6 , the specific processing flow is as follows:

[0051] (1) The hyperspectral data cubes in the polarization directions of 0°, 60°, and 120° first pass through the hyperspectral data cube resolution module to resolve the hyperspectral data cube into single-band image data in the polarization directions of 0°, 60°, and 120°.

[0052] (2) According to the spectral calibration coefficient, assign the correct central wavelength parameter to the single-band image data to achieve spectral calibration.

[0053] (3) According to the radiometric calibration coefficient, convert the image gray values in each band of image data into quantitative radiance images and reflectance images to achieve radiometric calibration.

[0054] (4) According to the polarization calibration coefficient, correct the polarization measurement error of the entire optical system, as well as correct the polarization direction installation and rotation error of the polarizer to achieve polarization calibration.

[0055] (5) Calculate the spectral polarization information through the Stokes formula to obtain the hyperspectral Stokes parameter data cube (including S0, S1, S2 parameters) and the hyperspectral degree of polarization data cube (DoLP). The specific calculation formulas are as follows.

[0056]

[0057]

[0058]

[0059]

[0060] It should be noted that the above control acquisition unit and data sorting system together constitute a data acquisition control and processing system, which can be implemented by a combination of software and hardware, and will not be specifically elaborated here.

[0061] When the polarization hyperspectral imaging device based on the micro-nano Fabry-Perot resonator provided in this application is in use, polarization information in different bands is acquired pixel by pixel. The schematic diagram of the acquisition device is as Figure 4 shown, and the specific steps are as follows:

[0062] (1) The incident light captured from the spatial two-dimensional target is polychromatic incompletely polarized light, which first passes through a band-pass filter to obtain band-selected polychromatic incompletely polarized light.

[0063] (2) This polychromatic incompletely polarized light passes through a high-extinction-ratio polarizer (i.e., the first polarizer) in the polarization analyzer to achieve the polarization analysis process and is converted into polychromatic linearly polarized light. In order to reduce the influence of subsequent optical devices on the properties of linearly polarized light, the polychromatic linearly polarized light passes through a depolarizer in the polarization analyzer to retain the amplitude component in the linearly polarized light and convert the polychromatic linearly polarized light into polychromatic pseudo-random incompletely polarized light.

[0064] (3) This polychromatic pseudo-random incompletely polarized light continues to pass through a 5×5 micro-nano F-P resonator array to obtain monochromatic light. Since the spectral selection bands at different positions in the 5×5 micro-nano F-P resonator array are different, the obtained monochromatic light is of different bands.

[0065] (4) The monochromatic light of different bands after polarization analysis converges to a single pixel of the SCMOS imaging sensor, and the acquisition of single-band polarization information is completed. When the 5×5 array simultaneously completes spectral separation and convergence, the acquisition of 25-band polarization information at a certain point in the two-dimensional scene is completed. The single-pixel single-band imaging process is as Figure 5 shown.

[0066] (5) Based on the data collected by the data acquisition control and processing system, the processing as shown in Figure 6 is performed to obtain the processing results as shown in Figure 7 and Figure 8 .

[0067] In summary, the frame-type polarization hyperspectral imaging device based on the micro-nano F-P resonator array provided in this application has the following advantages:

[0068] (1) This device can achieve high-speed acquisition of frame-type polarization hyperspectral image information.

[0069] (2) Due to the adoption of the micro-nano F-P resonator array, the spectral coverage range includes visible light to near infrared (600 nm - 1000 nm), enabling the acquisition of fast polarization information and real-time spectral information. The acquired polarization hyperspectral data has high spatial resolution, spectral resolution, and high polarization measurement accuracy.

[0070] (3) This device is composed of a combination of a high-speed rotating broadband high extinction ratio polarizer and a depolarizer, which not only realizes the function of fast polarization analysis at 0°, 60°, and 120°, but also solves the problem of the interference of linearly polarized light after polarization analysis by subsequent optical devices.

[0071] (4) This device is composed of a combination of devices such as a band-pass filter, a micro-nano F-P resonator array, and a microlens array, achieving pixel-level spectral gating at the micron scale and having a compact and small structure.

[0072] (5) The imaging module in this device uses an SCMOS imaging sensor, enabling the entire device to maintain a high detection efficiency under the conditions of small volume and low power consumption.

[0073] Overall, in terms of the optical system, the present invention provides a frame-type polarization hyperspectral imaging device with a simple structure, high polarization imaging accuracy, wide spectral coverage range, and high spectral resolution, solving the problems of quickly obtaining polarization hyperspectral image information of two-dimensional space targets and high-speed processing of polarization hyperspectral image information, etc.; on the basis of polarization imaging technology, the present invention integrates the fast pixel-level spectral separation technology of the micro-nano F-P resonator array, greatly simplifying the hyperspectral imaging structure.

[0074] The structure, features, and effects of the present invention have been described in detail based on the embodiments shown in the drawings above. The above are only the preferred embodiments of the present invention, but the present invention is not limited to the scope defined by the drawings. Any changes made according to the concept of the present invention, or equivalent embodiments modified to equivalent changes, still within the spirit covered by the specification and drawings, shall be within the protection scope of the present invention.

Claims

1. A polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity, characterized in that: include: A first optical lens group, an electrically controlled polarization analyzer module including a first polarizer and a depolarizer, a micro-nano Fabry-Perot resonant cavity array, a second optical lens group and a detector, and a data acquisition, control and processing system are sequentially arranged along the direction of the incident light; The first optical lens assembly is used to collect light emitted by a two-dimensional space target as incident light, wherein the incident light is complex incompletely polarized light; The electrically controlled polarization analyzer module, comprising a first polarizer and a depolarizer, is configured to analyze the incompletely polarized light into linearly polarized light with different polarization directions based on the first polarizer; and to convert the linearly polarized light into incompletely polarized light with pseudo-random polarization based on the depolarizer; The micro-nano Fabry-Perot resonant cavity array is used to obtain spectra of multiple wavelength bands of the linearly polarized light in each direction; the micro-nano Fabry-Perot resonant cavity array includes multiple Fabry-Perot resonant cavity units; the distance between the two oppositely arranged reflective elements of each Fabry-Perot resonant cavity unit is different; the second optical lens group is used to converge the spectrum of each wavelength band to the detector; The data acquisition control and processing system is used to control the electrically controlled polarization analysis module to obtain different polarization analysis directions, and to control the detector to snapshot the spectrum to be detected to obtain a hyperspectral data cube for each polarization direction, and to process the hyperspectral data cube.

2. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 1, characterized in that: The first optical lens group includes one of a telephoto objective lens and a microscope objective lens.

3. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 1, characterized in that: The electrically controlled polarization analysis module further includes a first motor; The first motor controls the rotation of the first polarizer to obtain polarizers with different polarization analysis directions; The input end of the first motor is connected to the output end of the data acquisition, control and processing system.

4. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 3, characterized in that: The depolarizer is arranged along the direction of the incident light and between the first polarizer and the micro-nano Fabry-Perot resonant cavity array.

5. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 1, characterized in that: The second optical lens group is a micro lens array; The microlens array and the micro-nano Fabry-Perot resonant cavity array are arranged in a one-to-one correspondence.

6. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 1, characterized in that: The detector is a SCMOS sensor.

7. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 1, characterized in that: The different polarization analysis directions include a 0° polarization analysis direction, a 60° polarization analysis direction, and a 120° polarization analysis direction.

8. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to any one of claims 1 to 7, characterized in that: The polarization hyperspectral imaging device further includes: a first bandpass filter arranged along the direction of incident light; The first bandpass filter is arranged on a side of the first optical lens assembly away from the electrically controlled polarization analyzer module.

9. The polarization hyperspectral imaging device based on a micro-nano Fabry-Perot cavity according to claim 8, characterized in that: The first bandpass filter includes a high-pass filter and a near-infrared filter.

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