Three-dimensional object encryption and decryption method and system based on vortex light array regulation and control
By using a vortex light array control method, a three-dimensional model is constructed and layered processing is performed. Combined with specific technologies, a reusable encrypted hologram is generated, which solves the problem of difficulty in restoring information of three-dimensional objects in existing technologies and achieves high-fidelity independent reconstruction and improved security.
Patent Information
- Application Number
- CN202511172777.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-08-21
- Publication Date
- 2025-12-12
AI Technical Summary
Existing 3D information encryption technologies based on vortex beams are difficult to simultaneously restore 3D object information with spatial depth structure, and the decryption quality is easily affected by crosstalk and noise during the reuse of multiple images.
The method of vortex light array control is adopted. By constructing a three-dimensional model, depth and intensity information are extracted. Layered processing is carried out using tomography. Multiplexed encrypted holograms are generated by combining random phase modulation, angular spectrum diffraction, off-axis holography and digital blazed grating. The holograms are decrypted by matching the arrangement of Laguerre-Gaussian vortex lights.
It significantly improves the security and information capacity of 3D optical holographic encryption, reduces interlayer crosstalk, and achieves high-fidelity independent reconstruction of 3D object information.
Smart Images
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Abstract
Description
Technical Field
[0001] This application relates to the field of information encryption and decryption technology, specifically to a three-dimensional object encryption and decryption method and system based on vortex light array control. Background Technology
[0002] With the continuous growth of information technology and data security demands, the encryption and transmission of information about three-dimensional objects has become an important research direction in modern optical information processing. Vortex beams, with their helical phase structure, theoretically have an arbitrary helical phase index, exhibiting high orthogonality and scalability, and are therefore widely used as encryption keys.
[0003] However, most systems rely solely on the spiral phase index for encryption, lacking a multi-degree-of-freedom collaborative mechanism. On one hand, current vortex beam-based 3D information encryption typically only achieves selective reconstruction of layer information, making it difficult to simultaneously restore 3D object information with spatial depth structure. On the other hand, during multi-image multiplexing, experiments still suffer from noise introduced by crosstalk and device errors caused by multiplexing, thus affecting decryption quality.
[0004] Currently, research on vortex beam holographic encryption technology still needs to provide more degrees of freedom to improve information encryption security. The encryption and decryption method and system of three-dimensional objects based on vortex light array control provides a new approach for this field. Summary of the Invention
[0005] This invention provides a three-dimensional object encryption and decryption method and system based on vortex optical array control, which effectively reduces interlayer crosstalk in decrypting three-dimensional object information, greatly increases information channels, and improves the information capacity and encryption security of optical holography.
[0006] The first aspect of this application provides a three-dimensional object encryption and decryption method based on vortex light array control, comprising:
[0007] Construct a three-dimensional model and extract its depth and intensity information;
[0008] Using tomography, the intensity information is processed in layers based on the depth information of a three-dimensional object, and then combined with the sampling point matrix to generate the target image.
[0009] The generated target image is modulated using random phases, and then angular spectral diffraction is used to generate a hologram containing depth information. A selected hologram is then constructed by combining specific spiral phase indices and radial indices. Then, off-axis holography and digital blazed grating techniques are introduced to stitch and modulate the selected holograms to generate a multiplexed encrypted hologram.
[0010] When decrypting a multiplexed encrypted hologram, high-fidelity independent reconstruction of the three-dimensional object information can only be achieved by matching the Laguerre-Gaussian vortex light used during encryption, the arrangement of the Laguerre-Gaussian vortex light, and the depth of the corresponding three-dimensional information.
[0011] A second aspect of this application provides a three-dimensional object encryption / decryption system based on vortex light array control, comprising:
[0012] The construction module is used to generate a three-dimensional model and extract its depth and intensity information;
[0013] The processing module is used to perform layered processing on the three-dimensional model, and then combine each layer with the sampling point matrix to generate the target image;
[0014] The encryption module is used to modulate the generated target image with random phases, then use angular spectral diffraction to generate a hologram containing depth information, and then construct a selected hologram by combining specific spiral phase indices and radial indices. Finally, off-axis holography and digital blazed grating techniques are introduced to stitch and modulate the selected holograms to generate a multiplexed encrypted hologram.
[0015] The decryption module is used to decrypt the multiplexed encrypted hologram. Only by matching the Laguerre-Gaussian vortex light used during encryption, the arrangement of the Laguerre-Gaussian vortex light, and the depth of the corresponding three-dimensional information can the high-fidelity independent reconstruction of the three-dimensional object information be achieved.
[0016] As can be seen from the above, according to the 3D object encryption and decryption method and system based on vortex light array control provided in this application, a 3D model is constructed and its depth and intensity information are extracted; using tomography, the intensity information is processed layer by layer through the depth information of the 3D object, and then combined with the sampling point array to generate the target image; the generated target image is modulated with random phase, and then angular spectral diffraction is used to generate a hologram containing depth information. Then, a selected hologram is constructed by combining specific spiral phase index and radial index. Then, off-axis holography and digital blazed grating technology are introduced to stitch and modulate the selected hologram to generate a multiplexed encrypted hologram; the multiplexed encrypted hologram is decrypted. Only by matching the Laguerre-Gaussian vortex light used in encryption, the arrangement of the Laguerre-Gaussian vortex light, and the depth of the corresponding 3D information can the high-fidelity independent reconstruction of the 3D object information be achieved, which significantly improves the security of 3D optical holographic encryption. Attached Figure Description
[0017] Figure 1 A schematic diagram of the basic process of a three-dimensional object encryption and decryption method based on vortex light array control provided in an embodiment of this application;
[0018] Figure 2 is a schematic diagram of the principle of a three-dimensional object encryption process controlled by a vortex light array according to an embodiment of this application;
[0019] Figure 3 A schematic diagram illustrating the principle of a vortex light array-controlled three-dimensional object decryption process provided in an embodiment of this application;
[0020] Figure 4 This is a schematic diagram of a 3D object encryption / decryption system module controlled by a vortex optical array, provided in two embodiments of this application.
[0021] Figure 5 This is a schematic diagram of the decryption module in a vortex light array-controlled three-dimensional object encryption and decryption system provided in the second embodiment of this application;
[0022] In the picture:
[0023] 1. Laser; 2. Half-wave plate; 3. Mirror; 4. Beam expander; 5. Collimating lens; 6. First beam splitter; 7. First spatial light modulator; 8. First lens; 9. Second beam splitter; 10. Second spatial light modulator; 11. Second lens; 12. Filter; 13. Third lens; 14. CCD camera. Detailed Implementation
[0024] The technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments, not all embodiments.
[0025] like Figure 1 The diagram shows a basic flowchart of a 3D object encryption / decryption method based on vortex light array control. This 3D object holographic encryption / decryption method includes the following steps:
[0026] Step 101: Construct a three-dimensional model and extract its depth and intensity information; In this embodiment, a three-dimensional model of a small train is generated, and its depth and intensity information are extracted.
[0027] Step 102: Using tomography, the intensity information is processed into layers based on the depth information of the 3D object, and then combined with the sampling point matrix to generate the target image. In this embodiment, tomography is used to process the 3D information of the toy train into layers, dividing it into N layers based on its depth information, denoted as C1, C2...C1. j , where j represents a separate layer with a sequential index, and each layer is combined with a sampling point matrix to generate the target image;
[0028] Step 103: The generated target image is modulated using random phases, and then a depth-preserving hologram is generated using angular spectral diffraction. A selected hologram is then constructed by combining specific spiral phase indices and radial indices. Then, off-axis holography and digital blazed grating techniques are introduced to stitch and modulate the selected holograms to generate a multiplexed encrypted hologram.
[0029] Specifically, in this embodiment, the expression for the propagation of a Laguerre-Gaussian mode vortex beam with specific helical phase and radial indices along the z-direction is as follows:
[0030]
[0031] Among them, C pl Let ω0 be a constant, ω0 be the radius of the fundamental mode beam waist, l be the helical phase index, and p be the radial index. To associate Laguerre polynomials.
[0032] In this embodiment, when the encrypted Laguerre-Gaussian mode vortex beam illuminates the preserved hologram, each spatial frequency component of the hologram will be superimposed with the Laguerre-Gaussian mode vortex beam, which can be expressed as:
[0033]
[0034] Where (x,y) and (u,v) represent the coordinates in the hologram plane and the image plane, respectively, and R p Let p represent the complex amplitude distribution function of a Laguerre-Gaussian beam with radial exponent p.
[0035] Step 104: Decrypt the multiplexed encrypted hologram. Only by matching the vortex light of the Laguerre-Gaussian mode used during encryption, the arrangement of the vortex light of the Laguerre-Gaussian mode, and the depth of the corresponding three-dimensional information can the three-dimensional object information be reconstructed independently with high fidelity.
[0036] like Figure 4 As shown in the second embodiment of this application, a three-dimensional object encryption and decryption system based on vortex light array control is provided. The system mainly includes:
[0037] Construction module 401 is used to generate a three-dimensional solid model and extract its depth and intensity information;
[0038] Processing module 402 is used to perform layered processing on the three-dimensional model, and then combine it with the sampling point matrix to generate the target image;
[0039] The encryption module 403 is used to modulate the generated target image using random phases, then use angular spectral diffraction to generate a hologram containing depth information, and then construct a selected hologram by combining specific spiral phase index and radial index. Then, off-axis holography and digital blazed grating technology are introduced to stitch and modulate the selected hologram to generate a multiplexed encrypted hologram.
[0040] The decryption module 404 is used to decrypt the multiplexed encrypted hologram. Only by matching the Laguerre-Gaussian vortex light used during encryption, the arrangement of the Laguerre-Gaussian vortex light, and the depth of the corresponding three-dimensional information can the high-fidelity independent reconstruction of the three-dimensional object information be achieved.
[0041] Specifically, Figure 5 This is a schematic diagram of the decryption module in a vortex light array-controlled three-dimensional object encryption and decryption system provided in two embodiments of this application. The structure includes a light source module, a first modulation module, a second modulation module, and an imaging module.
[0042] In this embodiment, the light source module includes a laser 1, a half-wave plate 2, a mirror 3, a beam expander 4, and a collimating lens 5. The laser 1 is used to provide a Gaussian beam; the half-wave plate is mainly used to change the polarization direction of the light and adjust the light intensity, so that the Gaussian beam is converted into a specific polarization state that matches the SLM; the beam expander 4 is used to increase the diameter of the beam and adjust its divergence angle; and the collimating lens 5 is used to convert the diverging beam into a parallel beam.
[0043] In this embodiment, the first modulation module includes a first beam splitter 6, a first spatial light modulator 7, and a first lens 8; the first spatial light modulator 7 is used to load the phase map of the Laguerre-Gaussian mode vortex light array.
[0044] In this embodiment, the second modulation module includes a second beam splitter 9, a second spatial light modulator 10, a second lens 11, a filter 12, a third lens 13, and f between the third lens 13 and the CCD camera; the second spatial light modulator 10 is used to load a multiplexed encrypted hologram after being stitched and modulated from multiple selected holograms.
[0045] Specifically, the four-fold focal length from the first spatial light modulator 7 to the second spatial light modulator 10 is to ensure that the array of Laguerre-Gaussian vortex beams on the first spatial light modulator 7 is accurately projected onto the second spatial light modulator 10.
[0046] In this example, the imaging module includes a CCD camera 14.
[0047] Specifically, the distance f between the second spatial light modulator 10 and the third lens 13 and the CCD camera 14 is set to selectively transmit the frequency components of the target image information contained in the decrypted image and filter out diffraction orders, thereby improving the image reconstruction results.
[0048] Based on the method and system described in this application, a three-dimensional model is constructed and its depth and intensity information are extracted. Using tomography, the intensity information is processed layer by layer based on the depth information of the three-dimensional object, and then combined with a sampling array to generate a target image. The generated target image is modulated using random phase, and then angular spectral diffraction is used to generate a hologram containing depth information. A selected hologram is then constructed by combining specific spiral phase indices and radial indices. Further, off-axis holography and digital blazed grating techniques are introduced to stitch and modulate the selected hologram to generate a multiplexed encrypted hologram. The multiplexed encrypted hologram is decrypted; only by matching the Laguerre-Gaussian vortex beams used in encryption, the arrangement of the Laguerre-Gaussian vortex beams, and the depth of the corresponding three-dimensional information can high-fidelity independent reconstruction of the three-dimensional object information be achieved. Through the implementation of the method and system of this application, the encryption and decryption process of three-dimensional information is achieved by controlling the vortex beam array, significantly improving the security of three-dimensional optical holographic encryption.
[0049] The specific embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present invention shall be considered equivalent substitutions and shall be included within the protection scope of the present invention.
Claims
1. A three-dimensional object encryption and decryption method based on vortex light array regulation, characterized in that, Specifically comprising the following steps: Construct a three-dimensional model, extract its depth information and intensity information; Using tomographic technology, the intensity information is processed by layering the depth information of the three-dimensional object, and then combined with the sampling point array to generate the target image; The generated target image is modulated using random phase, and then the angular spectrum diffraction is used to generate a reserved hologram containing depth information, and then a specific spiral phase index and radial index are combined to construct a selection hologram, and then further introduce off-axis holographic technology and digital blazed grating technology to splice and modulate the selection hologram to generate a multiplexing encryption hologram; The decryption processing of the multiplexing encryption hologram, only the matching of the Laguerre-Gaussian mode vortex light used in encryption, the arrangement of the Laguerre-Gaussian mode vortex light and the depth of the corresponding three-dimensional information can realize the high-fidelity independent reconstruction of the three-dimensional object information.
2. The three-dimensional object encryption and decryption method based on vortex light array regulation according to claim 1, wherein, The specific spiral phase index and radial index are used as the encryption and decryption key to encrypt the three-dimensional information, and the expression of the Laguerre-Gaussian mode vortex beam containing the specific spiral phase index and radial index along the z direction is shown in formula (1): where C is a constant, ω0is the waist radius of the fundamental mode, l is the helical phase index, p represents the radial index, pl is the associated Laguerre polynomial. 3.The three-dimensional object encryption and decryption method based on vortex light array regulation according to claim 1, wherein, In order to suppress the crosstalk noise in the image multiplexing process, the off-axis holographic technology is used to construct a multi-channel multiplexing hologram; in order to ensure the image reconstruction on the optical axis, the digital blazed grating technology is introduced to modulate the multiplexing encryption hologram, which greatly increases the multiplexing channel capacity and realizes the effective separation and reproduction of multiple layers in the axial space.
4. The three-dimensional object encryption and decryption method based on vortex light array regulation according to claim 1, characterized in that, In the decryption process of three-dimensional information, only the matching of the Laguerre-Gaussian mode vortex light used in encryption, the arrangement of the Laguerre-Gaussian mode vortex light and the depth of the corresponding three-dimensional information can realize the high-fidelity independent reconstruction of the three-dimensional object information; when the encrypted Laguerre-Gaussian mode vortex light beam irradiates the reserved hologram, each spatial frequency component of the hologram will be superimposed with the Laguerre-Gaussian mode vortex light, as shown in formula (2): where (x, y) and (u, v) represent the coordinates in the hologram plane and the image plane, respectively, R p denotes the Laguerre-Gaussian beam complex amplitude distribution function with radial index p.
5. A three-dimensional object encryption and decryption system based on vortex light array regulation, characterized in that, It comprises: The construction module is used for generating a three-dimensional model, extracting its depth information and intensity information; The processing module is used for layering the three-dimensional model, and then combining it with the sampling point array to generate the target image; The encryption module is used for modulating the generated target image using random phase, and then using angular spectrum diffraction to generate a reserved hologram containing depth information, and then combining a specific spiral phase index and radial index to construct a selection hologram, and then further introducing off-axis holographic technology and digital blazed grating technology to splice and modulate the selection hologram to generate a multiplexing encryption hologram; The decryption module is used for decrypting the multiplexing encryption hologram, and only the matching of the Laguerre-Gaussian mode vortex light used in encryption, the arrangement of the Laguerre-Gaussian mode vortex light and the depth of the corresponding three-dimensional information can realize the high-fidelity independent reconstruction of the three-dimensional object information.
6. The three-dimensional object encryption and decryption system based on vortex light array regulation according to claim 5, wherein, The decryption module device is divided into a light source module, a first modulation module, a second modulation module and an imaging module; The light source module comprises a laser, a half-wave plate, a mirror, a beam expander and a collimating lens; The first modulation module comprises a first beam splitter, a first spatial light modulator and a first lens; The second modulation module comprises a second beam splitter, a second spatial light modulator, a second lens, a filter, a third lens, and an f between the third lens and a CCD camera; The imaging module only comprises a CCD camera. 7.The three-dimensional object encryption and decryption system based on vortex light array regulation according to claim 5, wherein, The first spatial light modulator is used for loading a phase map of a Laguerre-Gaussian mode vortex light array; and the second spatial light modulator is used for loading a multiplexed encrypted hologram after being modulated by a plurality of selected holograms. The laser is used for providing a Gaussian light beam. The half-wave plate is mainly used for changing a polarization direction of light and adjusting light intensity, so that the Gaussian light beam is converted into a specific polarization state matched with the SLM. 8.The three-dimensional object encryption and decryption system based on vortex light array regulation according to claim 5, wherein, The distance between the first spatial light modulator and the second spatial light modulator is four times of a focal length, and the distance between the second spatial light modulator and the f between the third lens and the CCD camera is also four times of the focal length. The four times of the focal length between the first spatial light modulator and the second spatial light modulator is to ensure that the array of the Laguerre-Gaussian mode vortex light beam on the first spatial light modulator is accurately projected onto the second spatial light modulator. The four times of the focal length between the second spatial light modulator and the f between the third lens and the CCD camera is to selectively transmit frequency components of target image information contained in a decrypted image and filter out diffraction orders, so as to improve an image reconstruction result.