Application of a spectral encoding device in spectral and polarization reconstruction and preparation method thereof

Abstract

The application relates to an application of a spectrum coding device in spectrum and polarization reconstruction and a preparation method, the spectrum coding device comprises an image sensor and a plurality of composite curved surface films, the inner wall surface of the composite curved surface film is arranged towards the image sensor, the composite curved surface film comprises a first curved surface film and a second curved surface film, the inner wall surface of the second curved surface film is attached to the outer wall surface of the first curved surface film, and the refractive indexes of the first curved surface film and the second curved surface film are different; incident light is incident from the outer wall surface of the second curved surface film to form a characteristic pattern at the image sensor, and the characteristic pattern is reconstructed to obtain at least polarization information corresponding to the incident light.

Description

Technical Field

[0001] This invention relates to the field of spectral and polarization reconstruction, and in particular to the application and preparation method of a spectral encoding device in spectral and polarization reconstruction. Background Technology

[0002] Optical sensors have wide applications in daily life, scientific research, and industry. In recent years, with the continuous development of micro-nano fabrication technology and micro-nano optical devices, many highly integrated miniature optical sensors have been extensively researched and developed, such as miniature spectrometers and on-chip polarization detectors.

[0003] Based on different principles, miniature spectrometers can be divided into dispersive, narrowband filtering, Fourier transform, and computational reconstruction types. Among them, computational reconstruction spectrometers replace the physical spectroscopic elements and optical paths in conventional spectrometers by modulating and encoding spectral information and using algorithms to decode it. This can greatly reduce the size and weight of the device and has enormous potential for the miniaturization of spectrometers.

[0004] As the requirements for sensing tasks become increasingly demanding, the realization of multidimensional optical field information sensing has become particularly important. While spectral detection is currently achievable, simultaneous polarization detection has not been fully explored. Existing research on simultaneous spectral and polarization detection largely relies on metasurface design to modulate both spectra and polarization. However, the fabrication of metasurfaces is relatively complex. Therefore, there is significant potential for developing compact spectral and polarization simultaneous detection systems with simple structures and straightforward fabrication processes. Summary of the Invention

[0005] Therefore, it is necessary to address the issue of high cost in synchronous detection of spectral and polarization by providing an application and fabrication method for a spectral encoding device in spectral and polarization reconstruction.

[0006] An application of a spectral coding device in spectral reconstruction, the spectral coding device including an image sensor and a plurality of composite curved films, the inner wall surface of the composite curved films being disposed facing the image sensor, the composite curved films including a first curved film and a second curved film, the inner wall surface of the second curved film being attached to the outer wall surface of the first curved film, the first curved film and the second curved film having different refractive indices;

[0007] Incident light enters from the outer wall of the second curved film to form a feature pattern at the image sensor, and the feature pattern is reconstructed to obtain at least the polarization information corresponding to the incident light.

[0008] The spectral encoding device of the present invention further includes a third curved film, which is located on the outer wall surface of the composite curved film, and the refractive index of the second curved film is between that of the third curved film and the first curved film.

[0009] The first curved surface film of this invention is made of zinc oxide, and the second curved surface film is made of silicon dioxide.

[0010] The composite curved surface membrane described in this invention is a non-spherical surface membrane.

[0011] Both the first curved surface film and the second curved surface film of the present invention are spherical films.

[0012] The present invention uses at least two monochromatic lights of different wavelengths in a reference polarization state as incident light to irradiate the outer wall surface of the second curved film to obtain feature patterns corresponding to at least two monochromatic lights;

[0013] A first correspondence is established, wherein the feature pattern corresponding to the monochromatic light is associated with the polarization information of the monochromatic light through the first correspondence;

[0014] The outer wall surface of the second curved film is irradiated with composite light as the incident light to obtain the feature pattern corresponding to the composite light.

[0015] Based on the feature pattern corresponding to the monochromatic light, the first correspondence, and the feature pattern corresponding to the composite light, the polarization information corresponding to the composite light is reconstructed.

[0016] The present invention constructs a second correspondence, wherein the feature pattern corresponding to the monochromatic light is associated with the spectral information of the monochromatic light through the second correspondence;

[0017] Based on the feature pattern corresponding to the monochromatic light, the second correspondence, and the feature pattern corresponding to the composite light, the spectrum corresponding to the composite light is reconstructed.

[0018] A method for preparing a spectral encoding device includes:

[0019] The image sensor is placed on one side of the transparent substrate;

[0020] Press the bottom surface of the transparent curved substrate against the other side of the transparent substrate;

[0021] A first curved film is prepared on the curved surface of the transparent curved substrate, and a second curved film is prepared on the side of the first curved film opposite to the transparent curved substrate, so as to obtain a composite curved film on the transparent curved substrate.

[0022] In this invention, a matching medium is covered on the side of the composite curved film facing away from the transparent curved substrate, and the refractive index of the matching medium is matched with that of the transparent curved substrate.

[0023] The matching medium described in this invention has a planar outer wall surface that faces away from the composite curved film.

[0024] The beneficial effects of this invention are as follows:

[0025] When composite light is incident on a composite curved film, it is modulated by the first and second curved films, forming a characteristic pattern consisting of multiple alternating bright and dark ring patterns. This pattern can be considered as the superposition of the characteristic patterns corresponding to each monochromatic light contained within the composite light. For any monochromatic light, the size, number, and spacing of the ring patterns vary with the wavelength of the monochromatic light, the rotation direction of the ring patterns varies with the polarization state of the monochromatic light, and the overall intensity information of the characteristic pattern varies with the intensity of the monochromatic light. Therefore, the characteristic pattern of composite light can serve as a visual information carrier of composite light. Through the characteristic pattern of composite light, the polarization and spectral information of the composite light can be obtained by reconstructing it using appropriate algorithms.

[0026] The combined effect of the first and second curved films can create different coding modulation effects for each monochromatic light component in the composite light. This allows the feature patterns corresponding to each monochromatic light to be fully separated from the feature patterns of the composite light during algorithm reconstruction. This avoids the aliasing of spectral or polarization information of some wavelength monochromatic light caused by the high correlation between the coding of different wavelength monochromatic lights and the overly similar corresponding feature patterns. This ensures the accuracy of spectral and polarization reconstruction information of the feature patterns. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the main structure of the spectral encoding device in Embodiment 1 of the present invention;

[0028] Figure 2 This is a schematic cross-sectional view of the composite curved surface membrane in Embodiment 1 of the present invention;

[0029] Figure 3 This is the characteristic pattern formed by monochromatic light at the image sensor in Embodiment 4 of the present invention;

[0030] Figure 4 This is a schematic cross-sectional view of the composite curved surface membrane in Embodiment 2 of the present invention;

[0031] Figure 5 This is a schematic diagram of the main structure of the spectral encoding device in Embodiment 3 of the present invention;

[0032] Figure 6 This is a schematic diagram of the calibration device in Embodiment 4 of the present invention;

[0033] Figure 7 The actual transmittance curve and theoretical transmittance curve of the composite curved film in Embodiment 3 of the present invention are shown.

[0034] Figure 8 This is a reconstructed image of the spectrum and feature pattern of the composite light in Embodiment 4 of the present invention;

[0035] Figure 9 The Stokes parameter S1 of the composite light and the Stokes parameter S1 obtained by reconstructing the feature pattern in Embodiment 4 of the present invention;

[0036] Figure 10 The Stokes parameter S2 of the composite light and the Stokes parameter S2 obtained by reconstructing the feature pattern in Embodiment 4 of the present invention;

[0037] Figure 11 The Stokes parameter S3 of the composite light and the Stokes parameter S3 obtained by reconstructing the feature pattern in Embodiment 4 of the present invention;

[0038] Figure 12 This is a top view of the composite curved surface membrane in Embodiment 1 of the present invention.

[0039] Figure label:

[0040] 1. Image sensor; 2. Composite curved film; 21. First curved film; 22. Second curved film; 23. Third curved film; 3. Transparent substrate; 31. Side plate; 4. Transparent curved substrate; 5. Matching medium; 6. Cover plate; 7. Computer; 8. Monochromator; 9. Depolarizing beam splitter; 10. Power meter. Detailed Implementation

[0041] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0042] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0046] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0047] Example 1:

[0048] See Figure 1 This embodiment provides a spectral encoding device, including an image sensor 1, a transparent substrate 3, a transparent curved substrate 4, and several composite curved films 2.

[0049] In this embodiment, the transparent substrate 3 is a quartz glass sheet with smooth and parallel planes on both sides. The image sensor 1 is an area array image sensor located below the lower surface of the transparent substrate 3, used to detect the feature patterns formed on the lower surface of the transparent substrate 3.

[0050] The transparent curved substrate 4 is disposed in the middle of the upper surface of the transparent substrate 3. The transparent curved substrate 4 is made of a wide-band high transparency material, such as optical glass such as K9 glass, BK7 glass, and fused silica glass, or organic polymers such as polydimethylsiloxane (PDMS) and polymethyl methacrylate (PMMA).

[0051] Specifically, the outer wall surface of the transparent curved substrate 4 includes a bottom surface and a curved surface. The bottom surface of the transparent curved substrate 4 is a plane, so the bottom surface of the transparent curved substrate 4 can be pressed tightly against the upper surface of the transparent substrate 3, so that there is no gap between the transparent curved substrate 4 and the transparent substrate 3. In this embodiment, the bottom surface of the transparent curved substrate 4 is circular, and its diameter ranges from 1 to 2 mm.

[0052] The shape of the transparent curved substrate 4 is not limited; it can be part of a sphere, an ellipsoid, a parabola, or other curved surfaces. The edge of the curved surface of the transparent curved substrate 4 coincides with the edge of the bottom surface, so that the edge of the curved surface can contact the upper surface of the transparent substrate 3. Thus, as long as the incident light is above the transparent substrate 3, it can enter the transparent curved substrate 4 at a certain angle, and then generate a feature pattern on the lower surface of the transparent substrate 3, which is captured by the image sensor 1. The height of the curved surface of the transparent curved substrate 4 on the bottom surface is less than 1 mm.

[0053] In this embodiment, the composite curved film 2 is approximately a spherical lens, with its inner wall facing the image sensor 1. The shape of the inner wall of the composite curved film 2 matches the shape of the transparent curved substrate 4, so that the inner wall of the composite curved film 2 can completely fit the surface of the transparent curved substrate 4, thereby avoiding gaps between the composite curved film 2 and the transparent curved substrate 4.

[0054] Typically, the incident light in a spectral encoding device is composite light, which contains multiple monochromatic lights. The intensity and polarization state of the monochromatic lights at different wavelengths in the composite light often differ. By reconstructing the feature pattern generated by the composite light using algorithms, the wavelength range, intensity, and / or polarization state information of the composite light can be obtained in a single exposure.

[0055] The composite light beam has a large cross-sectional area, and its illumination point is located on the outer wall surface of the composite curved film 2. (See also...) Figure 2 The composite curved surface mask 2 includes a first curved surface mask 21 and a second curved surface mask 22. In this embodiment, both the first curved surface mask 21 and the second curved surface mask 22 are spherical masks. For a single composite curved surface mask 2, the inner diameter of the second curved surface mask 22 is equal to the outer diameter of the first curved surface mask 21, so that the inner wall surface of the second curved surface mask 22 can fit against the outer wall surface of the first curved surface mask 21, avoiding gaps between the first curved surface mask 21 and the second curved surface mask 22.

[0056] The incident angle of the composite light varies at different positions on the outer wall of the second curved surface 22, resulting in different optical path lengths within the composite curved surface 2 and consequently, different phase changes. The closer to the edge of the second curved surface 22, the larger the incident angle of the composite light and the smaller the phase change. (See also...) Figure 12 The incident angle of the composite light at certain locations on the composite curved film 2 is not zero, resulting in different spectral functions for the s-wave and p-wave in the composite light. By constructing polar coordinates in the top view of the composite curved film 2, the polarization state of the composite light observed on the incident planes (planes OP1 and OP2) corresponding to different polar angles differs. Consequently, the spectral response functions of two points (P1 and P2) with the same center distance but different polar angles also differ. Based on these characteristics, the composite curved film 2 achieves synchronous modulation of the spectrum and polarization of the composite light.

[0057] Similarly, since both the first curved film 21 and the second curved film 22 are spherical films in this embodiment, the composite curved film 2 formed by the two is also a spherical film in this embodiment. Furthermore, since the radial thickness of both the first curved film 21 and the second curved film 22 is a constant, the radial thickness of the composite curved film 2 is also a constant value.

[0058] The first curved film 21 and the second curved film 22 have different refractive indices. For example, in this embodiment, the first curved film 21 is made of zinc oxide, and the second curved film 22 is made of silicon dioxide. The composite light is modulated and encoded when passing through the second curved film 22 and the first curved film 21, and finally forms a feature pattern corresponding to the composite light at the image sensor 1.

[0059] In this embodiment, by combining the first curved film 21 and the second curved film 22, the limitations on the geometric shape of the composite curved film 2, the limitation on the irradiation position of the composite light on the outer wall of the composite curved film 2, and / or the limitation on the irradiation angle of the composite light on the outer wall of the composite curved film 2 are reduced. This is beneficial for reconstructing the characteristic pattern generated by the composite light, thereby obtaining the spectral and polarization information of the composite light.

[0060] Example 2:

[0061] The difference between this embodiment and Embodiment 1 is that the composite curved surface film has at least two parts, see [link to embodiment]. Figure 4 In this embodiment, there are three composite curved films, each including a first curved film 21 made of zinc oxide and a second curved film 22 made of silicon dioxide. If the composite curved film is an aspherical film, the three composite curved films are stacked sequentially along the radius of curvature. If the composite curved film is a spherical film, the three composite curved films are stacked sequentially along the radial direction.

[0062] For two radially adjacent composite curved films, the outer wall surface of the inner composite curved film is bonded to the inner wall surface of the outer composite curved film, that is, the outer wall surface of the second curved film 22 is bonded to the inner wall surface of the first curved film 21, thereby avoiding gaps between adjacent composite curved films. Additionally, in this embodiment, a third curved film 23 is separately provided on the outer wall surface of the outermost second curved film 22. The third curved film 23 and the first curved film 21 are made of the same material, and therefore have the same refractive index.

[0063] This results in a seven-layer transmission structure consisting of four curved films made of zinc oxide and three curved films made of silicon dioxide, stacked radially in an alternating pattern. From the inside out, the thicknesses of the seven curved films are 65.2 nm, 62.1 nm, 161 nm, 56.3 nm, 161 nm, 62.1 nm, and 65.2 nm, respectively. The thickness and refractive index distribution of the seven-layer structure are obtained through algorithm optimization, which can significantly reduce the correlation with the encoding effect of different monochromatic lights, thereby enabling better reconfigurability of the feature patterns formed by composite light.

[0064] Example 3:

[0065] Based on Example 1, this embodiment provides a method for preparing a spectral encoding device, thereby resulting in several changes to the structure of the spectral encoding device between this embodiment and Example 1.

[0066] The preparation method of the spectral encoding device in this embodiment specifically includes the following steps:

[0067] Step S1: Press the bottom surface of the transparent curved substrate 4 onto the middle position of the upper surface of the transparent substrate 3;

[0068] Step S2: The first and second curved films are sequentially deposited alternately on the curved surface of the transparent curved substrate 4 to form the stacked structure of the composite curved film 2 in Example 2. Finally, the third curved film is deposited to form a seven-layer transmission structure. The deposition methods include, but are not limited to, physical vapor deposition methods such as magnetron sputtering, resistance thermal evaporation, electron beam evaporation, ion plating, and molecular beam epitaxy, as well as chemical vapor deposition methods such as low-pressure chemical vapor deposition, plasma-enhanced chemical vapor deposition, and photon chemical vapor deposition.

[0069] Step S3: A side plate 31 is attached to the edge of the upper surface of the transparent substrate 3. The side plate 31 is also made of quartz glass. The side plate 31 and the transparent substrate 3 enclose each other to form a receiving cavity. The transparent curved substrate 4 and the composite curved film 2 are located in the middle of the receiving cavity.

[0070] Step S4: Fill the cavity with matching medium 5 so that the matching medium 5 covers the outermost first curved film. The refractive index of the matching medium 5 should match the refractive index of the transparent substrate 3 and the transparent curved substrate 4, i.e., be equal or consistent. The matching medium 5 can be microscope immersion oil, fiber optic refractive index matching liquid, polydimethylsiloxane (PDMS) or polymethyl methacrylate (PMMA).

[0071] Step S5: Attach the cover plate 6 above the receiving cavity to seal the receiving cavity. The cover plate 6 is also made of quartz glass.

[0072] Step S6: Place the image sensor 1 on the lower surface of the transparent substrate 3. The image sensor 1 can be a high-performance charge-coupled device image sensor (CCD) or complementary metal-oxide-semiconductor sensor (CMOS).

[0073] The structure of the final obtained spectral encoding device is as follows Figure 5 As shown.

[0074] To ensure that the modulation of the first and second curved films plays a major role, the upper surface of the cover plate 6 needs to be a plane so that the composite light energy is emitted in a direction perpendicular to the cover plate 6. This avoids severe distortion of the pattern acquired at the image sensor 1 and ensures the readability, information integrity, and subsequent reconfigurability of the final obtained pattern.

[0075] In this embodiment, when the composite light is directed toward the composite curved film 2 in a direction perpendicular to the transparent substrate 3, the thickness of the first curved film and the second curved film is minimized, so that the composite light is emitted onto the transparent substrate 3 in a direction perpendicular to the transparent substrate 3 and forms a pattern.

[0076] In some other embodiments, if the cover plate 6 is not provided, the matching medium 5 needs to be flat, with the outer surface of the composite curved film 2 facing away from it.

[0077] In this embodiment, the film quality of the seven-layer curved film was verified using composite light in the 400-800nm ​​wavelength band. Specifically, the transmittance curve of the seven-layer curved film was calculated, and the transmittance curve of the seven-layer curved film was also directly detected using a Cary 5000 spectrometer. (See [link to Cary 5000 spectrometer]). Figure 7 It can be seen that the theoretical and actual values ​​of the transmittance curves of the seven-layer curved film in this embodiment are in good agreement. The transparent curved substrate is a 1.5mm H-K9L hemispherical lens; the composite curved film is prepared by magnetron sputtering, and the material of the composite curved film is zinc oxide (ZnO) and silicon dioxide (SiO2); the matching medium is microscope immersion oil; the quartz glass, image sensor 1, and all other materials used are commercially available and commonly available.

[0078] Example 4:

[0079] Based on the spectral encoding device prepared in Example 3, see [link / reference] Figure 6 This embodiment provides a calibration device, which specifically includes a computer 7, a monochromator 8, a multimode fiber, a collimating lens, a polarizer, a depolarizing beam splitter 9, a power meter 10, and the aforementioned spectral encoding device.

[0080] Based on this, this embodiment provides a method for reconstructing the feature pattern formed by composite light, including the following steps:

[0081] Step A1: Computer 7 controls monochromator 8 to output monochromatic light with a specific wavelength and polarization state. After beam expansion and modulation of polarization state using a polarizer, the beam is split by depolarizing beam splitter 9. One path is incident on composite curved film 2 to modulate and encode the monochromatic light, forming a feature pattern corresponding to the monochromatic light on the surface of image sensor 1 and being recorded. The other path uses power meter 10 to read the light intensity corresponding to the monochromatic light.

[0082] Since the wavelength and polarization state of the monochromatic light are pre-set by the monochromator 8 and the polarizer, they are known conditions, while the light intensity is obtained from the power meter 10. The polarization state of the monochromatic light at this time is taken as the reference polarization state.

[0083] Therefore, the wavelength, intensity, and reference polarization state of monochromatic light can all be mapped to the corresponding feature patterns of monochromatic light, specifically including the construction of a first correspondence and a second correspondence. The wavelength and intensity data of monochromatic light constitute the spectral information of monochromatic light, and this spectral information can be correlated with the corresponding feature patterns through the second correspondence.

[0084] The first correspondence is constructed based on the reference polarization state of monochromatic light and its characteristic pattern in that state. When the polarization state of monochromatic light changes, its corresponding characteristic pattern also changes. By using the characteristic pattern of the monochromatic light at that moment and the first correspondence, the polarization information of the monochromatic light at that moment can be obtained.

[0085] from Figure 3 As can be seen, the characteristic pattern corresponding to monochromatic light is characterized by multiple alternating bright and dark ring patterns from the inside out.

[0086] Step A2: Repeat step A1, changing the wavelength and intensity of the monochromatic light each time, while keeping the incident position of the monochromatic light at the composite curved film 2 unchanged, so that the image sensor 1 obtains the feature patterns formed by the modulation of monochromatic light of different wavelengths by the composite curved film 2.

[0087] Therefore, a first correspondence and a second correspondence can be constructed for monochromatic light of different wavelengths.

[0088] Step A3: Remove the monochromator 8, and use a composite light containing multiple monochromatic lights to be incident on the composite curved film 2 at the same angle as in step A1. The composite light is modulated and encoded by the composite curved film 2 to form a feature pattern corresponding to the composite light at the image sensor 1.

[0089] Step A4: The feature pattern corresponding to the composite light is composed of feature patterns corresponding to multiple monochromatic lights of different wavelengths. The feature pattern corresponding to the composite light is compared and calibrated with the feature patterns corresponding to monochromatic lights of different wavelengths obtained in Step A2 to determine the wavelengths of each monochromatic light contained in the composite light. Based on this, the polarization information of each monochromatic light in the composite light is reconstructed based on the first correspondence relationship of each monochromatic light. Based on the second correspondence relationship of each monochromatic light, the spectrum of each monochromatic light in the composite light is reconstructed.

[0090] Step A5: Superimpose the spectra corresponding to each monochromatic light obtained in Step A4 to obtain the spectrum corresponding to the composite light. Superimpose the polarization information corresponding to each monochromatic light obtained in Step A4 to obtain the polarization information corresponding to the composite light.

[0091] In this embodiment, linearly polarized light with a center wavelength of 550 nm and a bandwidth of 30 nm is used as the composite light to irradiate the composite curved film 2, thereby obtaining a feature pattern corresponding to the composite light. This feature pattern is then processed using the method described above for reconstructing feature patterns formed by the composite light, thereby obtaining the reconstructed spectrum of the composite light. (See also...) Figure 8 As can be seen, the spectrum obtained by reconstructing the composite light has a very good match with the actual spectrum. See also Figure 9-11 In this embodiment, the actual Stokes parameters S1, S2, and S3 of the composite light are also detected. At the same time, the Stokes parameters S1, S2, and S3 corresponding to the composite light are obtained through feature pattern reconstruction. It can be seen that there is a good matching degree between the actual Stokes parameters of the composite light and the Stokes parameters obtained by feature pattern reconstruction.

[0092] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0093] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. An application of a spectral encoding device in spectral and polarization reconstruction, characterized in that, The spectral encoding device includes an image sensor and several composite curved films. The inner wall surface of the composite curved films is disposed facing the image sensor. The composite curved films include a first curved film and a second curved film. The inner wall surface of the second curved film is attached to the outer wall surface of the first curved film. The refractive indices of the first curved film and the second curved film are different. Incident light enters from the outer wall surface of the second curved film to form a feature pattern at the image sensor, and the feature pattern is reconstructed to obtain at least the polarization information corresponding to the incident light; At least two monochromatic lights of different wavelengths in a reference polarization state are used as incident light to irradiate the outer wall surface of the second curved film to obtain feature patterns corresponding to at least two monochromatic lights; A first correspondence is established, wherein the feature pattern corresponding to the monochromatic light is associated with the polarization information of the monochromatic light through the first correspondence; The outer wall surface of the second curved film is irradiated with composite light as the incident light to obtain the feature pattern corresponding to the composite light. Based on the feature pattern corresponding to the monochromatic light, the first correspondence, and the feature pattern corresponding to the composite light, the polarization information corresponding to the composite light is reconstructed. A second correspondence is established, in which the feature pattern corresponding to the monochromatic light is associated with the spectral information of the monochromatic light through the second correspondence; Based on the feature pattern corresponding to the monochromatic light, the second correspondence, and the feature pattern corresponding to the composite light, the spectrum corresponding to the composite light is reconstructed.

2. The application of the spectral encoding device according to claim 1 in spectral and polarization reconstruction, characterized in that, The spectral encoding device further includes a third curved film located on the outer wall of the composite curved film, and the refractive index of the second curved film is between that of the third curved film and the first curved film.

3. The application of the spectral encoding device according to claim 1 in spectral and polarization reconstruction, characterized in that, The first curved mask is made of zinc oxide, and the second curved mask is made of silicon dioxide.

4. The application of the spectral encoding device according to claim 1 in spectral and polarization reconstruction, characterized in that, The composite curved surface membrane is a non-spherical membrane.

5. The application of the spectral encoding device according to claim 1 in spectral and polarization reconstruction, characterized in that, Both the first curved surface film and the second curved surface film are spherical films.

6. A method for preparing a spectral encoding device, characterized in that, include: The image sensor is placed on one side of the transparent substrate; Press the bottom surface of the transparent curved substrate against the other side of the transparent substrate; A first curved film is prepared on the curved surface of the transparent curved substrate, and a second curved film is prepared on the side of the first curved film opposite to the transparent curved substrate, so as to obtain a composite curved film on the transparent curved substrate. Among them, the incident angle of the composite light is different at different positions on the outer wall of the second curved film. The closer to the edge of the second curved film, the larger the incident angle of the composite light and the smaller the phase change. In addition, the incident angle of the composite light is not 0 at some positions on the composite curved film. The composite curved film has different spectral functions for the s-wave and p-wave in the composite light.

7. The method for preparing the spectral encoding device according to claim 6, characterized in that, A matching medium is applied to the side of the composite curved film facing away from the transparent curved substrate, and the refractive index of the matching medium is matched with that of the transparent curved substrate.

8. The method for preparing the spectral encoding device according to claim 7, characterized in that, The matching medium is a plane on the outer wall surface of the composite curved film, away from the outer wall surface.

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