A polarization imaging method and system based on galvanometer micro-scan super-resolution

Abstract

This invention provides a polarization imaging method and system based on galvanometer microscanning super-resolution, belonging to the field of polarization imaging technology. It includes: constructing a polarization imaging system based on galvanometer microscanning super-resolution, comprising a polarization imaging unit, a galvanometer scanning unit, a timing-driven unit, and an image acquisition and processing unit; constructing an optical path in the following order: target object → panchromatic lens → galvanometer → polarization sensor target surface; the galvanometer is installed at a 45° angle along the camera's optical axis, so that the incident light is reflected and perpendicularly incident on the sensor image surface; using the polarization imaging system based on galvanometer microscanning super-resolution, the galvanometer microscan is controlled in a timing sequence to sequentially acquire four frames of polarization images at 90°, 45°, 0°, and 135°; image registration and super-resolution reconstruction are performed using the four frames of polarization images, outputting a four-channel high-resolution polarization image along with the degree of polarization and polarization angle.

Description

Technical Field

[0001] This invention relates to the field of polarization imaging technology, and in particular to a polarization imaging method and system based on galvanometer microscanning super-resolution. Background Technology

[0002] Polarization, as the "fourth dimension" of light information besides intensity, spectrum, and phase, can accurately reflect unconventional information such as material composition and surface microstructure, and is therefore widely used in military camouflage identification, underwater imaging, and medical detection. Focal plane amplitude division polarization (DoFP) sensors are widely used due to their compact structure and good real-time performance; however, each pixel corresponds to only one polarization direction, and the resolution of four-way polarized images is only 1 / 4 of the original resolution, resulting in a significant resolution degradation and mosaic-like artifacts. Traditional solutions use interpolation reconstruction, but this leads to defects such as lost details, loss of high-frequency information, mosaic artifacts, and stepped jagged edges, affecting the accuracy of subsequent polarization image restoration, segmentation, and feature extraction. Existing prism scanning and piezoelectric ceramic driven scanning solutions suffer from complex structures, high control difficulty, high cost, and poor compatibility, making large-scale application difficult. Summary of the Invention

[0003] In view of this, the present invention provides a polarization imaging method and system based on galvanometer microscanning super-resolution. By constructing a time resampling technique to acquire missing information in situ, it can achieve 2x super-resolution, artifact-free, and low-noise polarization image acquisition, solving the defects of existing DoFP polarization imaging such as low resolution, interpolation artifacts, and high complexity of traditional super-resolution schemes.

[0004] The technical solution adopted by the embodiments of the present invention to solve its technical problem is as follows:

[0005] The first aspect of this invention provides a polarization imaging method based on galvanometer microscanning super-resolution, comprising:

[0006] A polarization imaging system based on galvanometer microscanning super-resolution was constructed, including a polarization imaging unit, a galvanometer scanning unit, a timing drive unit, and an image acquisition and processing unit:

[0007] The polarization imaging unit uses a focal plane amplitude-divided polarization sensor, and is equipped with a four-way polarization filter array of 0°, 45°, 90°, and 135° and a panchromatic lens for four-way polarization light intensity acquisition.

[0008] The galvanometer scanning unit uses a galvanometer to achieve sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, thereby causing sub-pixel displacement of the image plane.

[0009] The timing drive unit, including a signal generator and a drive board, is used to output periodic drive signals, synchronized with the camera's exposure frame rate, to achieve timing control of exposure-swing-stabilization-re-exposure;

[0010] The image acquisition and processing unit is used to complete image acquisition, buffering, subpixel registration, spatial reconstruction and super-resolution reconstruction;

[0011] The optical path is set up in the following order: target object → panchromatic lens → galvanometer → polarization sensor target surface; the galvanometer is installed at a 45° angle along the camera's optical axis so that the incident light is reflected and then incident perpendicularly onto the sensor image surface;

[0012] Using a polarization imaging system based on galvanometer microscanning super-resolution, the galvanometer microscanning is controlled in sequence to acquire four frames of polarization images at 90°, 45°, 0°, and 135°. The four frames of polarization images are used for image registration and super-resolution reconstruction, and output four-channel high-resolution polarization images as well as polarization degree and polarization angle.

[0013] Preferably, using a polarization imaging system based on galvanometer microscanning super-resolution, the galvanometer microscanning is controlled sequentially, and the image registration and super-resolution reconstruction process using four frames of polarization images includes:

[0014] The system is powered on and preheated for 5 minutes to stabilize temperature drift;

[0015] The timing drive unit determines the target swing angle θ based on the pixel size d and the lens focal length f, so that the image plane is displaced by d, the signal generator outputs a square wave, and the galvanometer returns to its position (0,0);

[0016] Camera exposure, at the initial position of the galvanometer The captured 90° polarized image is used as the first frame and stored in the buffer. The first frame corresponds to virtual pixels. ;

[0017] The galvanometer swings at an angle θ along the X direction, and after stabilizing for a duration of Δt, it is exposed. The 45° polarized image is acquired as the second frame and stored in the buffer. The second frame corresponds to the virtual pixel (x+d,y).

[0018] The galvanometer continues to swing along the Y direction by an angle θ. After stabilizing for a duration of Δt, it is exposed and a 0° polarized image is acquired as the 3rd frame and stored in the buffer. The 3rd frame corresponds to the virtual pixel (x+d, y+d).

[0019] The galvanometer continues to swing along the X direction by an angle of -θ. After stabilizing for a duration of △t, it is exposed and a 135° polarized image is acquired as the 4th frame and stored in the buffer. The 4th frame corresponds to the virtual pixel (x, y+d).

[0020] After acquiring 4 frames, proceed to image reconstruction. The four low-resolution images are rearranged into a 2×2 grid: Frame 1 → ; Frame 2 → (x+d,y); Frame 3 → (x+d,y+d); Frame 4 → (x,y+d), after recombination, a four-channel high-resolution polarization image is obtained;

[0021] The four-angle micro-scan and super-resolution reconstruction processes are executed cyclically to produce continuous super-resolution output.

[0022] Preferably, determining the target swing angle θ includes:

[0023] Using the reticle as a target, a reference image is acquired; the galvanometer driving voltage is gradually fine-tuned to change the swing angle; the sub-pixel offset of adjacent frame images is detected in real time; the driving parameter θ, whose displacement is exactly equal to d pixels, is locked to complete the calibration; the swing angle θ of the galvanometer and the image plane displacement d satisfy the mathematical model: d=2f·tan(θ)≈2f·θ, that is, θ=d / 2f, where f is the lens focal length.

[0024] Ideally, the degree of polarization is calculated. With polarization angle include:

[0025] ,

[0026] ,

[0027] In the formula, I 0° I 45° I 90° I 135° S1 represents the light intensity at 0°, 45°, 90°, and 135°; S0 represents the total light intensity; S1 represents the light intensity difference between polarization angles of 0° and 90°; and S2 represents the light intensity difference between polarization angles of 45° and 135°.

[0028] Preferably, the coaxiality deviation between the galvanometer lens and the sensor optical axis is ≤5μm; the angle between the galvanometer mirror normal and the optical axis is 45°.

[0029] Preferably, the galvanometer is a piezoelectric ceramic driven reflective galvanometer, which performs sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, with displacement repeatability ≤1 / 10 pixel and linear error ≤0.5%; the galvanometer surface size is ≥10mm, the operating voltage is 14.9V, the response time is ≤1ms, the scanning angle range is ±0.01°, and it is driven by a periodic square wave signal.

[0030] A second aspect of the present invention provides a polarization imaging system based on galvanometer microscanning super-resolution for performing the aforementioned method. The system includes a polarization imaging unit, a galvanometer scanning unit, a timing drive unit, and an image acquisition and processing unit.

[0031] The polarization imaging unit uses a focal plane amplitude-divided polarization sensor, and is equipped with a four-way polarization filter array of 0°, 45°, 90°, and 135° and a panchromatic lens for four-way polarization light intensity acquisition.

[0032] The galvanometer scanning unit uses a galvanometer to achieve sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, thereby causing sub-pixel displacement of the image plane.

[0033] The timing drive unit, including a signal generator and a drive board, is used to output periodic drive signals, synchronized with the camera's exposure frame rate, to achieve timing control of exposure-swing-stabilization-re-exposure;

[0034] The image acquisition and processing unit is used to complete image acquisition, buffering, subpixel registration, spatial reconstruction and super-resolution reconstruction, and output four-channel high-resolution polarization images as well as polarization degree and polarization angle.

[0035] As can be seen from the above technical solution, the polarization imaging method and system based on galvanometer micro-scanning super-resolution provided in this invention first constructs a polarization imaging system based on galvanometer micro-scanning super-resolution, including a polarization imaging unit, a galvanometer scanning unit, a timing drive unit, and an image acquisition and processing unit: the polarization imaging unit uses a focal plane amplitude-divided polarization sensor, configured with a 0°, 45°, 90°, 135° four-directional polarization filter array and a panchromatic lens for four-directional polarization intensity acquisition; the galvanometer scanning unit uses a galvanometer to achieve sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, causing sub-pixel displacement of the image plane; the timing drive unit is used to output periodic drive signals, which are synchronized with the camera exposure frame. Rate synchronization enables sequential control of exposure-oscillation-stabilization-re-exposure. The image acquisition and processing unit performs image acquisition, buffering, sub-pixel registration, spatial reconstruction, and super-resolution reconstruction. The optical path is constructed in the following order: target object → panchromatic lens → galvanometer → polarization sensor target surface. The galvanometer is installed at a 45° angle along the camera's optical axis, ensuring that the incident light is reflected and then incident perpendicularly onto the sensor's image plane. Using a polarization imaging system based on galvanometer micro-scanning super-resolution, the galvanometer micro-scanning is controlled sequentially to acquire four frames of polarization images at 90°, 45°, 0°, and 135°. Image registration and super-resolution reconstruction are performed using these four frames of polarization images, outputting four-channel high-resolution polarization images along with polarization degree and polarization angle. This invention employs piezoelectric ceramic-driven reflective galvanometers for periodic micro-scanning, utilizes temporal resampling technology to acquire missing information in situ, sequentially obtains image information from four different observation angles, and then achieves 2x super-resolution polarization image reconstruction at four polarization angles through 2×2 spatial reconstruction. Attached Figure Description

[0036] Figure 1 This is a diagram showing the projection relationship of the super-resolution imaging of the galvanometer displacement in this invention.

[0037] Figure 2 This is a schematic diagram illustrating the principle of polarization multi-frame image reconstruction according to the present invention.

[0038] Figure 3 This is a diagram of the super-resolution experimental setup for galvanometer microscanning of the present invention.

[0039] Figure 4 This is a comparison chart of MTF before and after super-resolution.

[0040] Figure 5 This is a comparison image of interpolation method and micro-scan super-resolution image. Detailed Implementation

[0041] The technical solution and effects of the present invention will be further described in detail below with reference to the accompanying drawings.

[0042] This invention provides a polarization imaging method and system based on galvanometer microscanning super-resolution. By constructing a time resampling technique, missing information is acquired in situ, achieving high-definition, 2x resolution acquisition of polarization images with minimal sacrifice of the polarization camera's temporal resolution.

[0043] refer to Figures 1-3 The polarization imaging system based on galvanometer microscanning super-resolution of the present invention includes a polarization imaging unit, a galvanometer scanning unit, a timing drive unit, and an image acquisition and processing unit:

[0044] The polarization imaging unit uses a focal plane amplitude-divided polarization sensor, and is equipped with a four-way polarization filter array of 0°, 45°, 90°, and 135° and a panchromatic lens for four-way polarization light intensity acquisition.

[0045] The galvanometer scanning unit uses a galvanometer to achieve sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, thereby causing sub-pixel displacement of the image plane.

[0046] The timing drive unit, including a signal generator and a drive board, is used to output periodic drive signals, synchronized with the camera's exposure frame rate, to achieve timing control of exposure-swing-stabilization-re-exposure;

[0047] The image acquisition and processing unit is used to complete image acquisition, buffering, subpixel registration, spatial reconstruction, and super-resolution reconstruction.

[0048] The specific implementation of the polarization imaging method based on galvanometer microscanning super-resolution of the present invention includes:

[0049] A polarization imaging system based on galvanometer microscanning super-resolution was constructed;

[0050] Building an optical path, such as Figure 3 As shown, the sequence is: target object → panchromatic lens → galvanometer → polarization sensor target surface; the galvanometer is installed at a 45° angle along the camera's optical axis so that the incident light is reflected and then incident perpendicularly onto the sensor image surface;

[0051] Using a polarization imaging system based on galvanometer microscanning super-resolution, the galvanometer microscanning is controlled in sequence to acquire four frames of polarization images at 90°, 45°, 0°, and 135°. The four frames of polarization images are used for image registration and super-resolution reconstruction, and output four-channel high-resolution polarization images as well as polarization degree and polarization angle.

[0052] Using a polarization imaging system based on galvanometer microscanning for super-resolution, the process of image registration and super-resolution reconstruction using four frames of polarization images, controlled sequentially by galvanometer microscanning, includes:

[0053] The system is powered on and preheated for 5 minutes to stabilize temperature drift;

[0054] The timing drive unit determines the target swing angle θ based on the pixel size d and the lens focal length f, so that the image plane is displaced by d, the signal generator outputs a square wave, and the galvanometer returns to its position (0,0);

[0055] Camera exposure, at the initial position of the galvanometer The captured 90° polarized image is used as the first frame and stored in the buffer. The first frame corresponds to virtual pixels. ;

[0056] The galvanometer swings at an angle θ along the X direction, and after stabilizing for a duration of Δt, it is exposed. The 45° polarized image is acquired as the second frame and stored in the buffer. The second frame corresponds to the virtual pixel (x+d,y).

[0057] The galvanometer continues to swing along the Y direction by an angle θ. After stabilizing for a duration of Δt, it is exposed and a 0° polarized image is acquired as the 3rd frame and stored in the buffer. The 3rd frame corresponds to the virtual pixel (x+d, y+d).

[0058] The galvanometer continues to swing along the X direction by an angle of -θ. After stabilizing for a duration of △t, it is exposed and a 135° polarized image is acquired as the 4th frame and stored in the buffer. The 4th frame corresponds to the virtual pixel (x, y+d).

[0059] After acquiring 4 frames, proceed to image reconstruction. The four low-resolution images are rearranged into a 2×2 grid: Frame 1 → ; Frame 2 → (x+d,y); Frame 3 → (x+d,y+d); Frame 4 → (x,y+d), after recombination, a four-channel high-resolution polarization image is obtained;

[0060] The four-angle micro-scan and super-resolution reconstruction processes are executed cyclically to produce continuous super-resolution output.

[0061] Determining the target swing angle θ includes:

[0062] Using the reticle as a target, a reference image is acquired; the galvanometer driving voltage is gradually fine-tuned to change the swing angle; the sub-pixel offset of adjacent frame images is detected in real time; the driving parameter θ, which is exactly equal to d pixels, is locked to complete the calibration; the swing angle θ of the galvanometer and the image plane displacement d satisfy the mathematical model: d=2f·tan(θ)≈2f·θ, that is, θ=d / 2f, where f is the lens focal length.

[0063] Ideally, the degree of polarization is calculated. With polarization angle include:

[0064] ,

[0065] ,

[0066] In the formula, I 0° I 45° I 90° I 135° S1 represents the light intensity at 0°, 45°, 90°, and 135°; S0 represents the total light intensity; S1 represents the light intensity difference between polarization angles of 0° and 90°; and S2 represents the light intensity difference between polarization angles of 45° and 135°.

[0067] The following is a specific embodiment, combined with Figure 3 The examples provided illustrate the solution of this invention in detail.

[0068] Polarization imaging unit: Employs an IMX250MYR focal plane amplitude-division polarization sensor, with a target area size of 2 / 3 inch, CMOS resolution of 2448×2048, and pixel size... The single-polarization direction resolution is 1224×1024. The lens uses a focal length of... It features a panchromatic fixed-focus lens with an aperture of F4.0. The sensor incorporates a four-directional polarizing filter array with 0°, 45°, 90°, and 135° polarization, arranged in a Bayer-type mosaic pattern.

[0069] Galvanometer scanning unit: Employs a piezoelectric ceramic-driven reflective galvanometer, enabling sub-pixel-level micro-amplitude oscillation in the X / Y two-dimensional directions. Displacement repeatability is ≤1 / 10 pixel, and linearity error is ≤0.5%. The galvanometer mirror surface size is ≥10mm, operating voltage is 14.9V, response time is ≤1ms, and scanning angle range is ±0.01°. Displacement accuracy reaches the sub-pixel level, power supply voltage is 14.9V, and it is driven by a periodic square wave signal.

[0070] Timing drive unit: Composed of a signal generator and a driver board, it outputs a periodic square wave signal, which is synchronized with the camera's exposure frame rate to achieve strict timing control of exposure-swing-stabilization-re-exposure.

[0071] Image acquisition and processing unit: Composed of an industrial control computer, image acquisition card, and processing software, it performs image acquisition, buffering, subpixel registration, spatial reconstruction, and super-resolution reconstruction, and outputs a four-channel high-resolution polarization image and DoLP and AoLP feature maps. It also performs spatial reconstruction of four low-resolution images, outputting a 2x super-resolution polarization image.

[0072] Light path setup: As shown in Figure 3, the light source uses uniform diffused white light illumination, and the target objects are high-frequency detailed objects such as reticles, checkerboard targets, and leaves.

[0073] Optical path sequence: target object → panchromatic lens → galvanometer → polarization sensor target surface.

[0074] The galvanometer is installed at a 45° angle along the optical axis of the camera, so that the incident light is reflected and then incident perpendicularly onto the sensor image plane, thus avoiding off-axis aberration and distortion.

[0075] Mechanical calibration requirements: the coaxiality deviation between the lens and the sensor optical axis is ≤5μm; the angle between the normal of the galvanometer surface and the optical axis is 45°; the system as a whole is rigidly fixed to avoid vibration and displacement.

[0076] Galvanometer displacement model and angle calibration:

[0077] according to Figure 1 The established coordinate relationship yields a mathematical model of the galvanometer's swing angle and the image plane displacement: To achieve single-pixel-level displacement, let ,but:

[0078] Substitute the parameters into this embodiment: , The calculation yields: .

[0079] Calibration steps:

[0080] 1) Acquire a baseline image using the reticle as the target;

[0081] 2) Gradually fine-tune the galvanometer driving voltage to change the swing angle;

[0082] 3) Real-time detection of sub-pixel offset between adjacent frames;

[0083] 4) Lock the driving parameter with the displacement exactly equal to 1 physical pixel to complete the calibration.

[0084] Timing control and four-frame acquisition:

[0085] Each set of super-resolution images is synthesized from four consecutive micro-scanned images, with the following sampling rules:

[0086] Frame 1: Initial position of the galvanometer Acquire 90° polarization, corresponding to virtual pixels ;

[0087] Frame 2: X-direction +1 pixel displacement, 45° polarization acquisition, corresponding to virtual pixels. ;

[0088] Frame 3: X+1, Y+1 pixel displacement, 0° polarization captured, corresponding to virtual pixels. ;

[0089] Frame 4: Y-direction displacement +1 pixel, 135° polarization captured, corresponding to virtual pixels. .

[0090] Timing flow:

[0091] 1) Power on the system and preheat for 5 minutes to stabilize temperature drift;

[0092] 2) The signal generator outputs a square wave, and the galvanometer returns to its original position (0,0);

[0093] 3) The camera exposes, captures the first frame, and stores it in the buffer;

[0094] 4) Move the galvanometer 1 pixel along the X direction, stabilize for 1ms, and then expose to capture the second frame;

[0095] 5) Move the galvanometer 1 pixel along both the X and Y axes, stabilize for 1ms, and then expose to capture the 3rd frame;

[0096] 6) Return the galvanometer to the X=0, Y+1 position, stabilize for 1ms, and then expose to capture the 4th frame;

[0097] 7) After 4 frames are acquired, proceed to image reconstruction;

[0098] 8) Execute in a loop to achieve continuous super-resolution output.

[0099] The camera frame rate was set to 60fps, and the micro-scan cycle was strictly synchronized with the exposure to avoid motion blur.

[0100] Image registration and super-resolution reconstruction:

[0101] Sub-pixel registration: Feature point matching and grayscale correlation registration are used to correct the offset caused by mechanical vibration and temperature drift, and the registration accuracy is better than 1 / 10 pixel.

[0102] Spatial reorganization: such as Figure 2 As shown, four 1224×1024 low-resolution images are rearranged into a 2×2 grid: Frame 1 → ; Frame 2 → ; Frame 3 → ; Frame 4 → After reconstruction, a 2448×2048 full-resolution polarization image was obtained, achieving a 2x super-resolution. The four polarization channels at 0°, 45°, 90°, and 135° were reconstructed to obtain four-channel high-resolution data.

[0103] Noise suppression: A four-frame multi-frame averaging algorithm is used to suppress shot noise and readout noise, thereby improving the image signal-to-noise ratio.

[0104] Polarization feature calculation: Calculate the degree of polarization based on the super-resolution image. With polarization angle After exceeding the score , The image texture is more continuous, the edges are sharper, and the noise is lower.

[0105] Image quality verification:

[0106] Table 1 Evaluation of the quality of interpolated reconstruction and microscan super-resolution images

[0107] As shown in Table 1, based on the two no-reference metrics BRISQUE and NIQE for evaluating image naturalness and quality, the galvanometer-based microscanning method proposed in this invention improves the image quality by 25.1% and 1.41 respectively, demonstrating the significant effect of the proposed method on image quality improvement.

[0108] from Figure 5 The results show that, compared to interpolation, the method proposed in this paper restores clearer text with significantly reduced internal noise. This is because the polarization angle alignment error is further amplified by the division during the DoLP solution process. Furthermore, the figures demonstrate that the method used in this patent produces sharp reticle edges without jagged edges or mosaic artifacts; the high-frequency details of the checkerboard and leaves are intact. / The noise in the feature map is significantly reduced.

[0109] MTF analysis such as Figure 4 As shown, the MTF (Mean Transformation Factor) of the high-frequency band of the image is significantly improved after super-resolution, while it decreases slightly in the mid-to-low frequency band, which can be compensated for by high-precision angle calibration. High frequencies are where image details are concentrated; higher high-frequency components mean more accurate restoration of image texture details and content.

[0110] This invention addresses the traditional To address issues such as reduced resolution of polarization sensors, loss of detail in interpolation methods, and mosaic artifacts, this invention employs a piezoelectric ceramic-driven reflective galvanometer for periodic micro-scanning, sequentially acquiring image information from four different observation angles. Then, a 2×2 spatial reconstruction method is used to achieve double-resolution polarization image reconstruction at the four polarization angles. The system consists of a polarization camera, galvanometer, temporal drive, and image reconstruction unit, achieving single-pixel-level displacement through precise control of the swing angle. Experiments show that compared to traditional interpolation methods, this invention can improve resolution by two times, eliminate artifacts and jagged edges, and improve the BRISQUE (Best Image Quality) index by 25.1%. and Image details are significantly improved. This invention is highly compatible, low-cost, and produces high-quality images, suitable for static or precisely controlled dynamic scenes, and can provide a high-quality data foundation for blind restoration and segmentation of polarization images.

[0111] The above-disclosed embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of the invention. Those skilled in the art will understand that implementing all or part of the above-described embodiments and making equivalent changes in accordance with the claims of the present invention are still within the scope of the invention.

Claims

1. A polarization imaging method based on galvanometer microscanning super-resolution, characterized in that, include: A polarization imaging system based on galvanometer microscanning super-resolution was constructed, including a polarization imaging unit, a galvanometer scanning unit, a timing drive unit, and an image acquisition and processing unit: The polarization imaging unit uses a focal plane amplitude-divided polarization sensor, and is equipped with a four-way polarization filter array of 0°, 45°, 90°, and 135° and a panchromatic lens for four-way polarization light intensity acquisition. The galvanometer scanning unit uses a galvanometer to achieve sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, thereby causing sub-pixel displacement of the image plane. The timing drive unit, including a signal generator and a drive board, is used to output periodic drive signals, synchronized with the camera's exposure frame rate, to achieve timing control of exposure-swing-stabilization-re-exposure; The image acquisition and processing unit is used to complete image acquisition, buffering, subpixel registration, spatial reconstruction and super-resolution reconstruction; The optical path is set up in the following order: target object → panchromatic lens → galvanometer → polarization sensor target surface; the galvanometer is installed at a 45° angle along the camera's optical axis so that the incident light is reflected and then incident perpendicularly onto the sensor image surface; Using a polarization imaging system based on galvanometer microscanning super-resolution, the galvanometer microscanning is controlled in sequence to acquire four frames of polarization images at 90°, 45°, 0°, and 135°. The four frames of polarization images are used for image registration and super-resolution reconstruction, and output four-channel high-resolution polarization images as well as polarization degree and polarization angle.

2. The polarization imaging method based on galvanometer microscanning super-resolution as described in claim 1, characterized in that, Using a polarization imaging system based on galvanometer microscanning for super-resolution, the process of image registration and super-resolution reconstruction using four frames of polarization images, controlled sequentially by galvanometer microscanning, includes: The system is powered on and preheated for 5 minutes to stabilize temperature drift; The timing drive unit determines the target swing angle θ based on the pixel size d and the lens focal length f, so that the image plane is displaced by d, the signal generator outputs a square wave, and the galvanometer returns to its position (0,0); Camera exposure, at the initial position of the galvanometer The captured 90° polarized image is used as the first frame and stored in the buffer. The first frame corresponds to virtual pixels. ; The galvanometer swings at an angle θ along the X direction, and after stabilizing for a duration of Δt, it is exposed. The 45° polarized image is acquired as the second frame and stored in the buffer. The second frame corresponds to the virtual pixel (x+d,y). The galvanometer continues to swing along the Y direction by an angle θ. After stabilizing for a duration of Δt, it is exposed and a 0° polarized image is acquired as the 3rd frame and stored in the buffer. The 3rd frame corresponds to the virtual pixel (x+d, y+d). The galvanometer continues to swing along the X direction by an angle of -θ. After stabilizing for a duration of △t, it is exposed and a 135° polarized image is acquired as the 4th frame and stored in the buffer. The 4th frame corresponds to the virtual pixel (x, y+d). After acquiring 4 frames, proceed to image reconstruction. The four low-resolution images are rearranged into a 2×2 grid: Frame 1 → ; Frame 2 → (x+d,y); Frame 3 → (x+d,y+d); Frame 4 → (x,y+d), after recombination, a four-channel high-resolution polarization image is obtained; The four-angle micro-scan and super-resolution reconstruction processes are executed cyclically to produce continuous super-resolution output.

3. The polarization imaging method based on galvanometer microscanning super-resolution as described in claim 2, characterized in that, Determining the target swing angle θ includes: Using the reticle as a target, a reference image is acquired; the galvanometer driving voltage is gradually fine-tuned to change the swing angle; the sub-pixel offset of adjacent frame images is detected in real time; the driving parameter θ, whose displacement is exactly equal to d pixels, is locked to complete the calibration; the swing angle θ of the galvanometer and the image plane displacement d satisfy the mathematical model: d=2f·tan(θ)≈2f·θ, that is, θ=d / 2f, where f is the lens focal length.

4. The polarization imaging method based on galvanometer microscanning super-resolution as described in claim 3, characterized in that, Calculate the degree of polarization With polarization angle include: , , In the formula, I 0° I 45° I 90° I 135° S1 represents the light intensity at 0°, 45°, 90°, and 135°; S0 represents the total light intensity; S1 represents the light intensity difference between polarization angles of 0° and 90°; and S2 represents the light intensity difference between polarization angles of 45° and 135°.

5. The polarization imaging method based on galvanometer microscanning super-resolution as described in claim 1, characterized in that, The coaxiality deviation between the galvanometer lens and the sensor optical axis is ≤5μm; the angle between the galvanometer mirror normal and the optical axis is 45°.

6. The polarization imaging method based on galvanometer microscanning super-resolution as described in claim 1, characterized in that, The galvanometer is a piezoelectric ceramic driven reflective galvanometer, which performs sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, with displacement repeatability ≤1 / 10 pixel and linear error ≤0.5%; the galvanometer surface size is ≥10mm, the working voltage is 14.9V, the response time is ≤1ms, the scanning angle range is ±0.01°, and it is driven by a periodic square wave signal.

7. A polarization imaging system based on galvanometer microscanning super-resolution, characterized in that, For performing the method according to any one of claims 1-6, the system includes a polarization imaging unit, a galvanometer scanning unit, a timing drive unit, and an image acquisition and processing unit: The polarization imaging unit uses a focal plane amplitude-divided polarization sensor, and is equipped with a four-way polarization filter array of 0°, 45°, 90°, and 135° and a panchromatic lens for four-way polarization light intensity acquisition. The galvanometer scanning unit uses a galvanometer to achieve sub-pixel-level micro-oscillation in the X / Y two-dimensional direction, thereby causing sub-pixel displacement of the image plane. The timing drive unit, including a signal generator and a drive board, is used to output periodic drive signals, synchronized with the camera's exposure frame rate, to achieve timing control of exposure-swing-stabilization-re-exposure; The image acquisition and processing unit is used to complete image acquisition, buffering, subpixel registration, spatial reconstruction and super-resolution reconstruction, and output four-channel high-resolution polarization images as well as polarization degree and polarization angle.

Images