Data storage methods and related equipment based on optical coherence tomography

Abstract

This invention relates to the field of data storage technology, specifically to a data storage method and related equipment based on optical coherence tomography (OCT). The data storage method includes the following steps: converting the raw data stream to be stored into an optical modulation signal with a depth dimension using a three-dimensional encoding module. The three-dimensional encoding module maps binary data into a multi-layer phase-amplitude composite encoding matrix based on a non-uniform sampling algorithm, wherein the spatial resolution of each layer matches the axial scanning accuracy of OCT. This invention constructs a depth-adaptive phase-amplitude composite encoding matrix using a non-uniform sampling algorithm, ensuring that the spatial resolution of each layer of data precisely matches the axial scanning characteristics of OCT, thus avoiding spectral overlap of inter-layer modulation signals from the signal source.

Description

Technical Field

[0001] This invention relates to the field of data storage technology, specifically to a data storage method and related equipment based on optical coherence tomography. Background Technology

[0002] In existing optical coherence tomography (OCT) data storage technologies, 3D data encoding typically relies on a uniform layer mapping mechanism. The spatial resolution of this static encoding matrix is ​​difficult to precisely match the depth dimension with the axial scanning accuracy of the optical system. Especially in multi-layer, high-density storage scenarios, fixed encoding rules can easily lead to nonlinear coupling effects in the optical modulation signals of adjacent data layers during writing, exacerbating interlayer crosstalk. Simultaneously, traditional interferometric signal demodulation employs a preset reference arm optical path compensation strategy, which cannot adapt to dynamic refractive index fluctuations caused by material heterogeneity or environmental disturbances in the storage medium. This results in the accumulation of axial positioning errors during tomographic reconstruction, significantly degrading the demodulated signal-to-noise ratio of scattering intensity and phase information. Furthermore, existing noise suppression methods are mostly limited to single-dimensional filtering, making it difficult to distinguish between internal scattering noise and interlayer aliasing signals. The linear error correction algorithms relied upon in the data recovery stage lack adaptability to the nonlinear error propagation under high-density storage, limiting the capacity limit of the storage device. Summary of the Invention

[0003] This disclosure proposes a data storage method and related equipment based on optical coherence tomography, aiming to overcome at least one of the defects existing in the prior art.

[0004] To achieve the above objectives, the technical solution disclosed in this invention is as follows:

[0005] According to one aspect of this disclosure, a data storage method based on optical coherence tomography is provided, the steps of which include:

[0006] The raw data stream to be stored is converted into an optical modulation signal with depth dimension through a three-dimensional encoding module. The three-dimensional encoding module maps binary data into a multi-layer phase-amplitude composite encoding matrix based on a non-uniform sampling algorithm, wherein the spatial resolution of each layer matches the axial scanning accuracy of optical coherence tomography.

[0007] A broadband, low-coherence beam is generated using a tunable laser source. The optical modulation signal is written into a predetermined depth position of the optical storage medium through a spatial light modulator and a dynamic focusing lens group. The writing process adopts a multi-focus parallel scanning strategy to ensure that the interval between adjacent data layers is less than the depth of field range of the optical system.

[0008] During the data reading stage, the optical storage medium is scanned by an optical coherence tomography system. Interference signals are collected simultaneously and the scattering intensity distribution and phase delay information of each data layer are demodulated. The optical path difference of the reference arm is dynamically compensated according to the refractive index distribution of the storage medium.

[0009] An adaptive noise suppression algorithm is used to reconstruct the interference signal in multiple dimensions, eliminating interlayer crosstalk and internal scattering noise of the medium, and generating a high-fidelity three-dimensional data matrix.

[0010] The three-dimensional data matrix is ​​converted into a recovery data stream by a quantum error correction decoder. The decoder dynamically corrects the bit error rate based on the topological correlation of adjacent data blocks and uses a deep belief network to verify data integrity for reliable recovery.

[0011] Furthermore, the step of mapping binary data into a multi-layer phase-amplitude composite coding matrix based on a non-uniform sampling algorithm includes:

[0012] The original data stream is divided into a sequence of frames of length L, and a discrete wavelet transform is performed on each frame to generate a high-frequency component H and a low-frequency component L.

[0013] The high-frequency component H is nonlinearly compressed and encoded to obtain the high-frequency component H', which is expressed as:

[0014] Where σ is the noise threshold, R is the cutoff frequency radius, γ is the shape adjustment factor, and H(u,v) is the complex value of the original high-frequency component at the frequency domain coordinate (u, v).

[0015] The high-frequency component H' and the low-frequency component L are superimposed with weights α and β to generate a composite coding matrix C:

[0016] Wherein, α and β control the contribution ratios of the low-frequency component L and the high-frequency component H' in the composite coding matrix, respectively, satisfying α 2 +β 2 = 1 to maintain energy conservation;

[0017] The composite coding matrix is ​​assigned to the N axial layers of the optical storage medium using a depth mapping function, which is:

[0018] Where z0 is the reference depth, n represents the layer number, and var(C n ) represents the variance of the nth layer matrix, and Δz represents the baseline interlayer spacing.

[0019] Furthermore, the implementation steps of the multi-focus parallel scanning strategy include:

[0020] Calculate the phase compensation function of the spatial light modulator based on the depth distribution of the target data layer:

[0021] Where λ is the wavelength of the light source, (x, y, z) is the focal position, (x0, y0, z0) is the focal reference position, and ∇ 2 Here, T(x,y,z) is the Laplace operator, T(x,y,z) is the temperature field of the medium, and η is the thermal distortion compensation coefficient.

[0022] Set the scanning path to meet the optimal motion trajectory time condition for multiple focal points:

[0023] , where t k Let μ be the dwell time of the k-th focus, K be the total number of focuses, and μ be the path weight factor. The constraint is that the distance between adjacent focuses is greater than the diffraction-limited distance. k , y k Let be the target position coordinates of the k-th focus in the horizontal plane, k∈[1,K], (x k-1 , y k-1 ): The coordinates of the previous position of the (k-1)th focus in the horizontal plane, used to calculate the Euclidean distance of the focus movement.

[0024] Furthermore, the dynamic correction rule of the quantum error correction decoder is as follows:

[0025] Detect the amplitude A and phase φ of the current data block. If the following conditions are met:

[0026] Then it is determined to be a modulation symbol. Where δ is the initial decision threshold, and BER t This represents the current bit error rate.

[0027] Update the threshold based on the correlation between adjacent data blocks:

[0028] Where ξ is the learning rate, σ is the smoothing factor, and BER target To set a bit error rate limit.

[0029] Furthermore, the optical storage medium comprises alternating deposited high-refractive-index photonic crystal layers and low-refractive-index spacer layers. The periodic structure bandgap wavelength of the photonic crystal layers is matched with the center wavelength of the writing laser to enhance the reflection signal-to-noise ratio of the data layers. The thickness of the spacer layer is set according to the axial resolution of optical coherence tomography to ensure that the minimum spacing between adjacent data layers is less than 1 / 2 of the system depth of field. The surface of the medium is covered with an anti-reflective coating and a hard protective layer. The protective layer is made of diamond-like carbon material with a thickness of 50-100 nanometers to balance optical transmittance and mechanical abrasion resistance.

[0030] Furthermore, the steps of the multi-focus parallel scanning strategy include:

[0031] A reference marker array is generated on the surface of the medium using a low-power probe beam, and the initial coordinates of each marker are recorded.

[0032] During data writing, a probe beam is periodically emitted to detect the position offset of the reference mark. If the offset exceeds the preset tolerance, the phase correction module of the spatial light modulator is triggered to realign the scan path.

[0033] After the data writing is completed, the reference marker is holographically verified. If irreversible deformation is found, the corresponding data area is marked as an unreliable storage area and a redundant backup mechanism is initiated.

[0034] Furthermore, when generating the composite encoding matrix, the three-dimensional encoding module embeds multiple layers of redundant error correction data, including:

[0035] Reed-Solomon error correction codes are added to the edge regions of each layer of the data matrix, with an error correction capacity of 15%-20% of the original data block;

[0036] A holographic verification layer is inserted every K layers along the axial depth direction. The verification layer contains a hash digest and parity check bit of the data from the adjacent K layers.

[0037] During the data recovery phase, the verification layer information is parsed first. If local data corruption is detected, cross-layer data repair is performed according to the redundancy coding rules.

[0038] Furthermore, during the writing process, the local temperature distribution of the optical storage medium is monitored in real time, and the laser power and focal position are dynamically adjusted according to the thermal expansion effect. The steps include:

[0039] Real-time temperature data of each data layer is collected by a distributed temperature sensor array integrated on the surface of the storage medium.

[0040] Based on the temperature dependence of the thermal expansion coefficient and refractive index of the medium, the focal point drift caused by the thermal lensing effect is calculated, and the focal point position is compensated by a dynamic focusing lens group.

[0041] Based on the preset power-temperature response curve, the output power of the tunable laser source is adjusted in a closed-loop control manner to stabilize the writing energy within the thermal saturation threshold of the medium, thereby avoiding material phase change or optical damage.

[0042] According to another aspect of this disclosure, a data storage system based on optical coherence tomography is provided for implementing the data storage method described above, the data storage system comprising:

[0043] A three-dimensional encoding module is used to convert the raw data stream into a multi-layer phase-amplitude composite encoding matrix;

[0044] A tunable laser source and spatial light modulator assembly are configured to generate a multifocal scanning beam and write it into an optical storage medium;

[0045] The tomographic scanning module, including a low-coherence interferometer and a dynamic optical path compensator, is used to acquire tomographic interference signals;

[0046] The signal processing module is used to execute adaptive noise suppression algorithms and 3D data reconstruction;

[0047] A quantum error correction decoder, based on a deep belief network, is used to achieve data recovery and integrity verification.

[0048] The spatial light modulator group includes a liquid crystal phase modulator and a micromirror array, and its response time τ satisfies:

[0049] Where Δz is the interlayer spacing, f is the refractive index of the medium, c is the speed of light, and NA is the numerical aperture of the objective lens.

[0050] According to another aspect of this disclosure, a data storage device is provided, which stores a computer program that, when executed by a processor, implements the data storage method based on optical coherence tomography as described above.

[0051] The beneficial effects of this invention are:

[0052] This invention constructs a depth-adaptive phase-amplitude composite encoding matrix using a non-uniform sampling algorithm, ensuring that the spatial resolution of each layer of data precisely matches the axial scanning characteristics of optical coherence tomography (OCT), thus avoiding spectral overlap of interlayer modulation signals at the signal source. The coordinated control of a dynamic focusing lens group and a multi-focus parallel scanning strategy compresses the interlayer spacing within the system's depth of field, and real-time refractive index feedback compensation based on the optical path difference of the reference arm eliminates phase drift of the interference signal caused by medium inhomogeneity. Furthermore, an adaptive noise suppression algorithm, through joint spatial-frequency-depth three-dimensional feature extraction, analyzes and removes the coupling components of interlayer crosstalk and volume scattering noise. Meanwhile, a quantum error correction decoder models the nonlinear error propagation path based on the topological correlation of data blocks, combining it with the probabilistic inference mechanism of a deep belief network to achieve fault-tolerant reconstruction of high aliasing signals at subwavelength scales. This allows optical modulation, tomographic demodulation, and error correction to form a closed-loop optimization, ultimately maintaining super-resolution data reading and writing and near-lossless recovery even under dynamic perturbations of the medium's refractive index.

[0053] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the following describes the preferred embodiments of the present invention in detail with reference to the accompanying drawings. Attached Figure Description

[0054] Figure 1 This is a flowchart of a data storage method based on optical coherence tomography in one embodiment of the present invention;

[0055] Figure 2 This is a schematic diagram of a non-uniform sampling encoding process in one embodiment of the present invention;

[0056] Figure 3 This is a schematic diagram of a depth mapping function in one embodiment of the present invention;

[0057] Figure 4 This is a schematic diagram of multi-focus phase compensation in one embodiment of the present invention;

[0058] Figure 5 This is a schematic diagram of quantum error correction threshold adjustment in one embodiment of the present invention;

[0059] Figure 6 This is a schematic diagram of a media layering structure in one embodiment of the present invention;

[0060] Figure 7 This is a schematic diagram of scan path optimization in one embodiment of the present invention;

[0061] Figure 8 This is a schematic diagram of temperature compensation in one embodiment of the present invention;

[0062] Figure 9 This is a schematic diagram of inter-layer crosstalk suppression in one embodiment of the present invention;

[0063] Figure 10 This is a schematic diagram of a redundant coding structure in one embodiment of the present invention;

[0064] Figure 11 This is a schematic diagram of three-dimensional data reconstruction in one embodiment of the present invention;

[0065] Figure 12 This is a schematic diagram of complex plane decision-making in quantum error correction decoding according to an embodiment of the present invention;

[0066] Figure 13 This is a schematic diagram of the dielectric layer structure and thermal expansion compensation in one embodiment of the present invention. Detailed Implementation

[0067] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0068] The term "comprising," and any variations thereof, used in the specification and claims of this application, is intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not necessarily limited to those explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or apparatus. Furthermore, the use of "and / or" in the specification and claims indicates at least one of the connected objects, such as A and / or B, indicating the inclusion of A alone, B alone, or both A and B.

[0069] In embodiments of the present invention, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" or "for example" in embodiments of the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Rather, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

[0070] The present invention provides the following preferred embodiments: Example

[0071] To address the challenges of matching spatial resolution with axial scanning accuracy, severe inter-layer crosstalk, and low demodulation signal-to-noise ratio in existing optical coherence tomography (OCT) data storage technologies, this embodiment provides a data storage method based on OCT. It optimizes the 3D encoding module based on a non-uniform sampling algorithm and combines a multi-focus parallel scanning strategy and an adaptive noise suppression algorithm to achieve high-fidelity data storage and recovery. Figure 1 As shown, the data storage method includes the following steps:

[0072] The raw data stream to be stored is converted into an optical modulation signal with depth dimension through a three-dimensional encoding module. The three-dimensional encoding module maps binary data into a multi-layer phase-amplitude composite encoding matrix based on a non-uniform sampling algorithm, where the spatial resolution of each layer matches the axial scanning accuracy of optical coherence tomography.

[0073] A broadband, low-coherence beam is generated using a tunable laser source. The optical modulation signal is written into a predetermined depth position of the optical storage medium through a spatial light modulator and a dynamic focusing lens group. The writing process adopts a multi-focus parallel scanning strategy to ensure that the interval between adjacent data layers is smaller than the depth of field range of the optical system.

[0074] During the data reading stage, the optical storage medium is scanned by an optical coherence tomography system. Interference signals are acquired simultaneously and the scattering intensity distribution and phase delay information of each data layer are demodulated. The optical path difference of the reference arm is dynamically compensated according to the refractive index distribution of the storage medium.

[0075] An adaptive noise suppression algorithm is used to reconstruct the interference signal in multiple dimensions, eliminating interlayer crosstalk and internal scattering noise of the medium, and generating a high-fidelity three-dimensional data matrix.

[0076] The three-dimensional data matrix is ​​converted into a recovery data stream by a quantum error correction decoder. The decoder dynamically corrects the bit error rate based on the topological correlation of adjacent data blocks and uses a deep belief network to verify data integrity for reliable recovery.

[0077] In this embodiment, the raw data stream is first processed by a 3D encoding module. This module employs a non-uniform sampling algorithm to map the binary data into a multi-layer phase-amplitude composite encoding matrix. Specifically, this module converts the raw data stream into an optically modulated signal with a depth dimension. The spatial resolution of each layer matches the axial scanning accuracy of optical coherence tomography, thereby avoiding spectral overlap between layers. It is important to understand that this non-uniform sampling algorithm can dynamically adjust the resolution of each layer according to the characteristics of the data, ensuring clarity and accuracy at different depth levels.

[0078] Furthermore, a broadband, low-coherence laser beam is generated using a tunable laser source, and the optical modulation signal is written to a predetermined depth position in the optical storage medium via a spatial light modulator and a dynamic focusing lens group. The writing process employs a multi-focus parallel scanning strategy to ensure that the interval between adjacent data layers is less than the depth of field range of the optical system. This multi-focus parallel scanning strategy improves the efficiency and accuracy of data writing by having multiple focal points operate simultaneously. It is understood that the multi-focus parallel scanning strategy not only reduces writing time but also effectively reduces inter-layer crosstalk, such as... Figure 9 As shown, this improves the reliability of data storage.

[0079] During the data readout phase, an optical coherence tomography (OCT) system is used to perform tomographic scanning of the optical storage medium, simultaneously acquiring interference signals and demodulating the scattering intensity distribution and phase delay information of each data layer. The optical path difference of the reference arm is dynamically compensated according to the refractive index distribution of the storage medium to eliminate phase drift of the interference signal caused by medium inhomogeneity. It is important to understand that the dynamic compensation mechanism can adjust the optical path difference of the reference arm in real time to ensure the stability of the interference signal, thereby improving the demodulation signal-to-noise ratio.

[0080] Furthermore, an adaptive noise suppression algorithm is employed to reconstruct the interference signal in multiple dimensions, eliminating interlayer crosstalk and internal scattering noise within the medium, and generating a high-fidelity three-dimensional data matrix. The adaptive noise suppression algorithm analyzes and removes the coupling components of interlayer crosstalk and volume scattering noise through joint space-frequency-depth three-dimensional feature extraction. Understandably, this multi-dimensional reconstruction method can significantly improve the accuracy and reliability of data recovery, ensuring that the data is not affected by noise during the reading process.

[0081] Finally, the three-dimensional data matrix is ​​converted into a recovered data stream using a quantum error correction decoder. The quantum error correction decoder dynamically adjusts the bit error rate based on the topological correlation of adjacent data blocks and utilizes a deep belief network to verify data integrity for reliable recovery. It's important to understand that the quantum error correction decoder can dynamically adjust the error correction strategy based on the correlation of adjacent data blocks, improving the accuracy and integrity of data recovery. The deep belief network is used to verify data integrity, ensuring that no data is lost or corrupted during the recovery process.

[0082] In this embodiment, the multi-layer phase-amplitude composite coding matrix constructed based on the non-uniform sampling algorithm ensures that the spatial resolution of each layer matches the axial scanning accuracy of optical coherence tomography, avoiding spectral overlap of inter-layer modulation signals from the signal source. The multi-focus parallel scanning strategy and dynamic optical path compensation further improve data writing efficiency and demodulation signal-to-noise ratio, while the adaptive noise suppression algorithm and quantum error correction decoder enhance the accuracy of data recovery. Example

[0083] To address the balance issue of high-frequency and low-frequency components in the composite encoding matrix of existing optical coherence tomography (OCT) data storage technologies, this embodiment further optimizes the three-dimensional encoding module based on a non-uniform sampling algorithm. This ensures that the spatial resolution and axial scanning accuracy of each layer are matched, and improves the fidelity of data storage. Figure 2 As shown.

[0084] In this embodiment, the original data stream is first segmented into a sequence of frames of length L. A discrete wavelet transform is performed on each frame to generate a high-frequency component H and a low-frequency component L. The high-frequency component H is then nonlinearly compressed and encoded to obtain a high-frequency component H'. The expression for the nonlinear compression encoding is:

[0085] In this equation, σ is the noise threshold, used to control the degree of compression of high-frequency components; R is the cutoff frequency radius, which determines the frequency range of high-frequency components; γ is the shape adjustment factor, affecting the distribution shape of high-frequency components; and H(u,v) is the complex value of the original high-frequency component at the frequency domain coordinates (u,v). It is important to understand that this nonlinear compression coding method can effectively reduce noise in high-frequency components and improve signal clarity.

[0086] Furthermore, the high-frequency component H' and the low-frequency component L are superimposed with weights α and β to generate a composite coding matrix C. The superposition formula is:

[0087] Where α and β control the contribution ratios of the low-frequency component L and the high-frequency component H' in the composite coding matrix, respectively, satisfying α 2 +β 2= 1 to maintain energy conservation. It is understandable that by adjusting the values ​​of α and β, the ratio of high-frequency to low-frequency components can be optimized while ensuring energy conservation, thereby improving the fidelity of data storage.

[0088] Furthermore, the composite coding matrix is ​​assigned to the N axial layers of the optical storage medium using a depth mapping function. The depth mapping function is:

[0089] Where z0 is the reference depth, n represents the layer number, and var(C n Let be the variance of the nth layer matrix, and Δz be the baseline interlayer spacing. For example... Figure 3 As shown, this depth mapping method can dynamically adjust the interlayer spacing according to the variance of each layer matrix, ensuring that the spatial resolution of each layer matches the axial scanning accuracy of optical coherence tomography, thereby avoiding spectral overlap of interlayer signals.

[0090] In this embodiment, the multi-layer phase-amplitude composite coding matrix constructed based on a non-uniform sampling algorithm ensures that the spatial resolution and axial scanning accuracy of each layer are matched, avoiding spectral overlap of inter-layer modulated signals from the signal source. Simultaneously, nonlinear compression coding and weighted superposition improve the fidelity of data storage. The benefit of this embodiment lies in improving the accuracy and reliability of data storage by optimizing the processing of high-frequency and low-frequency components. Example

[0091] To address the implementation challenges of multifocal parallel scanning strategies in existing optical coherence tomography data storage technologies, this embodiment further refines the specific implementation steps of the multifocal parallel scanning strategy, ensuring that the interval between adjacent data layers is less than the depth of field of the optical system, thereby improving data writing efficiency and accuracy.

[0092] In this embodiment, the phase compensation function of the spatial light modulator is calculated based on the depth distribution of the target data layer. The expression for the phase compensation function is:

[0093] Where λ is the wavelength of the light source, (x, y, z) is the focal position, (x0, y0, z0) is the focal reference position, and ∇ 2 Let be the Laplace operator, T(x,y,z) be the temperature field of the medium, and η be the thermal distortion compensation coefficient. For example... Figure 4 and Figure 8 As shown, this phase compensation function can dynamically adjust the phase according to the focal position and the medium temperature field, thereby ensuring accurate focusing of multiple focal points.

[0094] Furthermore, the scanning path is set to satisfy the optimal time condition for the motion trajectory of multiple focal points. The expression for the optimal time condition is:

[0095] , where t k Let μ be the dwell time of the k-th focus, K be the total number of focuses, and μ be the path weight factor. The constraint is that the distance between adjacent focuses is greater than the diffraction-limited distance. k , y k Let be the target position coordinates of the k-th focus in the horizontal plane, k∈[1,K], (x k-1 , y k-1 ): The coordinates of the previous position of the (k-1)th focus in the horizontal plane, used to calculate the Euclidean distance of focus movement. It can be understood that by optimizing the scan path, the movement time between focuses can be reduced, thus improving data writing efficiency.

[0096] This embodiment reduces inter-layer crosstalk by precisely controlling the position and path of the focus, such as... Figures 7 to 9 As shown in the figure. Through this embodiment, the multi-focus parallel scanning strategy ensures that the interval between adjacent data layers is less than the depth of field range of the optical system by dynamically adjusting the phase compensation function and optimizing the scanning path, thereby improving the efficiency and accuracy of data writing. Example

[0097] To address the issue of dynamic correction rules in quantum error correction decoders in existing optical coherence tomography data storage technologies, this embodiment further optimizes the dynamic correction rules of quantum error correction decoders to ensure the accuracy and integrity of data recovery.

[0098] In this embodiment, the amplitude A and phase φ of the current data block are detected. If the following conditions are met:

[0099] Then it is determined to be a modulation symbol. Where i is the imaginary unit, δ is the initial decision threshold, and BER t This represents the current bit error rate. For example... Figure 5 and Figure 12 As shown, this dynamic decision method can adjust the decision threshold according to the current bit error rate, thereby improving the accuracy of data recovery.

[0100] Furthermore, the threshold is updated based on the correlation between adjacent data blocks. The threshold update formula is:

[0101] Where ξ is the learning rate, σ is the smoothing factor, and BER target To set a limit on the bit error rate. It is understandable that by dynamically adjusting the decision threshold, the data recovery process can be gradually optimized based on the correlation between adjacent data blocks, thereby improving data integrity and accuracy.

[0102] In this embodiment, the dynamic correction rules of the quantum error correction decoder ensure the accuracy and integrity of data recovery by dynamically adjusting the decision threshold and optimizing the data recovery process. The benefit of this embodiment is that it improves the accuracy of data recovery through fine-grained control of the decision threshold. Example

[0103] To address the issues of reflection signal-to-noise ratio and mechanical abrasion resistance of optical storage media in existing optical coherence tomography data storage technologies, this embodiment further optimizes the design of the optical storage media to ensure the reflection signal-to-noise ratio and mechanical performance of the data layer.

[0104] like Figure 6 As shown, in this embodiment, the optical storage medium includes alternating layers of high-refractive-index photonic crystal and low-refractive-index spacers. The periodic bandgap wavelength of the photonic crystal layers matches the center wavelength of the writing laser to enhance the signal-to-noise ratio of the data layer. It should be understood that this design effectively increases the reflectivity of the data layer, thereby improving the signal-to-noise ratio for data reading.

[0105] Furthermore, the thickness of the spacer layer is set according to the axial resolution of optical coherence tomography to ensure that the minimum spacing between adjacent data layers is less than half of the system depth of field. It is understood that by optimizing the thickness of the spacer layer, the minimum spacing between adjacent data layers can be ensured, thereby reducing inter-layer crosstalk and improving the reliability of data storage.

[0106] Furthermore, the surface of the medium is covered with an anti-reflective coating and a hard protective layer. The protective layer, made of diamond-like carbon material, is 50-100 nanometers thick to balance optical transmittance and mechanical abrasion resistance. It is important to understand that this protective layer not only improves the optical transmittance of the medium but also enhances its mechanical abrasion resistance, extending its service life.

[0107] The advantage of this embodiment is that the durability of data storage is improved through the design of the media structure. The design of the optical storage media improves the reflection signal-to-noise ratio and mechanical properties of the data layer by optimizing the structure of the photonic crystal layer and the spacer layer, as well as by adding an anti-reflective coating and a hard protective layer. Example

[0108] To address the stability issues of multifocal parallel scanning strategies in existing optical coherence tomography data storage technologies, this embodiment further optimizes the specific implementation steps of the multifocal parallel scanning strategy. This ensures that deviations in the scanning path can be corrected in real time during data writing, and that holographic imaging verification is performed after writing is completed, thereby improving the accuracy of data storage.

[0109] In this embodiment, a reference marker array is first generated on the surface of the medium using a low-power probe beam, and the initial coordinates of each marker are recorded. These reference markers are used to monitor changes in the position of the medium surface during data writing. It is important to understand that the generation and recording of the reference marker array is fundamental to ensuring the accuracy of subsequent calibration.

[0110] Furthermore, during data writing, a probe beam is periodically emitted to detect the positional offset of the reference marker. If the offset exceeds a preset tolerance, the phase correction module of the spatial light modulator is triggered to realign the scan path. This dynamic correction mechanism can adjust the scan path in real time, ensuring the accuracy of data writing. It is understandable that real-time monitoring and correction can effectively reduce scan path deviations caused by medium surface deformation or external interference, thereby improving the reliability of data writing.

[0111] After data writing is complete, holographic imaging verification is performed on the reference marker. If irreversible deformation is detected, the corresponding data area is marked as an unreliable storage area, and a redundant backup mechanism is initiated. Holographic imaging verification can comprehensively check the state of the medium surface, ensuring the integrity of data storage. It is important to understand that holographic imaging verification can promptly detect and address irreversible deformation of the medium surface, thereby preventing data corruption. Example

[0112] To address the reliability issues in data recovery within existing optical coherence tomography (OCT) data storage technologies, this embodiment further optimizes the design of the three-dimensional encoding module, such as... Figure 10 As shown, multi-layered redundant error correction data is embedded to improve the data storage recovery capability.

[0113] In this embodiment, the 3D encoding module embeds multiple layers of redundant error-correcting data when generating the composite encoding matrix. Specifically, Reed-Solomon error-correcting codes are added to the edge regions of each layer of the data matrix, with an error-correcting capacity of 15%-20% of the original data block. It should be understood that Reed-Solomon error-correcting codes can effectively correct errors during data transmission and improve the reliability of data recovery.

[0114] Furthermore, holographic verification layers are inserted every K layers along the axial depth direction. Each verification layer contains a hash digest and parity bits of the data from the adjacent K layers. These holographic verification layers not only provide additional verification information but also enable cross-layer verification of data integrity. Understandably, through these holographic verification layers, localized data corruption can be quickly detected and repaired during the data recovery phase, improving the efficiency and accuracy of data recovery.

[0115] In other words, during the data recovery phase, the verification layer information is parsed first. If local data corruption is detected, cross-layer data repair is performed according to redundancy coding rules. This hierarchical verification and repair mechanism ensures the comprehensiveness and accuracy of data recovery. It's important to understand that multi-layered redundancy error correction design can improve the data storage recovery capability. Example

[0116] To address the focus drift issue caused by thermal expansion in existing optical coherence tomography (OCT) data storage technologies, this embodiment further optimizes the temperature monitoring and dynamic adjustment mechanism during the writing process, ensuring the stability of laser power and focus position. Figure 13 As shown, this improves the accuracy and reliability of data writing.

[0117] In this embodiment, a distributed temperature sensor array integrated on the surface of the storage medium collects real-time temperature data for each data layer. These temperature sensors can monitor the temperature distribution on the medium surface in real time, providing a basis for subsequent dynamic adjustments. It is important to understand that real-time temperature monitoring is fundamental to ensuring the stability of laser power and focus position.

[0118] Furthermore, based on the temperature dependence of the medium's thermal expansion coefficient and refractive index, the focal drift caused by the thermal lensing effect is calculated, and sub-micron-level compensation is performed on the focal position using a dynamic focusing lens group. This dynamic compensation mechanism can adjust the focal position in real time, ensuring the accuracy of data writing. It is understandable that through precise calculation and dynamic adjustment, focal drift caused by thermal expansion can be effectively reduced, improving the reliability of data writing.

[0119] Based on a preset power-temperature response curve, the output power of the tunable laser source is adjusted using a closed-loop control method to stabilize the writing energy within the thermal saturation threshold of the medium, avoiding material phase transitions or optical damage. The closed-loop control mechanism dynamically adjusts the laser power based on real-time temperature data, ensuring the stability of the writing energy. It's important to understand that closed-loop control effectively prevents writing energy instability caused by temperature fluctuations, thereby improving data writing accuracy. Example

[0120] To address the issue of inter-module collaboration in existing optical coherence tomography data storage systems, this embodiment further optimizes the overall system design, ensuring efficient collaboration between modules and improving data storage performance and reliability.

[0121] In this embodiment, the data storage system includes several key modules: a three-dimensional encoding module, a tunable laser source and spatial light modulator group, a tomographic scanning module, a signal processing module, and a quantum error correction decoder. The three-dimensional encoding module is used to convert the raw data stream into a multi-layer phase-amplitude composite encoding matrix, ensuring efficient data encoding. It is important to understand that the three-dimensional encoding module is the first step in data storage, and its performance directly affects subsequent data writing and reading.

[0122] Furthermore, the tunable laser source and spatial light modulator array are configured to generate a multifocal scanning beam and write it into an optical storage medium. The spatial light modulator array includes a liquid crystal phase modulator and a micromirror array, whose response time τ satisfies:

[0123] Where Δz is the interlayer spacing, f is the refractive index of the medium, c is the speed of light, and NA is the numerical aperture of the objective lens. It is important to understand that the limitation of response time ensures the efficient generation and writing of multifocal scanning beams, improving the accuracy and speed of data writing.

[0124] Furthermore, the tomographic scanning module includes a low-coherence interferometer and a dynamic optical path compensator for acquiring tomographic interference signals. The low-coherence interferometer provides high-resolution tomographic images, while the dynamic optical path compensator adjusts the optical path difference of the reference arm in real time, ensuring the stability and accuracy of the interference signal. Understandably, the efficient collaborative operation of the tomographic scanning module is crucial for data acquisition.

[0125] Furthermore, the signal processing module is used to execute adaptive noise suppression algorithms and 3D data reconstruction, eliminating interlayer crosstalk and internal scattering noise within the medium, and generating a high-fidelity 3D data matrix, such as... Figure 11 As shown, the quantum error correction decoder, based on a deep belief network, is used for data recovery and integrity verification. It's important to understand that the collaborative work of the signal processing module and the quantum error correction decoder ensures the integrity of the recovered data. Example

[0126] To address the practical application challenges of existing optical coherence tomography data storage methods, this embodiment further optimizes the computer program design to ensure efficient operation of the data storage method in real-world systems, thereby enhancing the practicality of data storage.

[0127] In this embodiment, the data storage method is implemented through a computer program. When the program is executed by the processor, the data storage method based on optical coherence tomography, as described above, can be implemented. The program design fully considers the collaborative work of each module and the efficiency of data processing. It is important to understand that the design of the computer program is fundamental to ensuring the efficient operation of the data storage method in a real system.

[0128] Furthermore, the program includes key functional modules such as a 3D encoding module, a multi-focus parallel scanning strategy, an adaptive noise suppression algorithm, and a quantum error correction decoder. The 3D encoding module is responsible for converting the raw data stream into a multi-layer phase-amplitude composite encoding matrix; the multi-focus parallel scanning strategy ensures the efficiency and accuracy of data writing; and the adaptive noise suppression algorithm and quantum error correction decoder ensure the high fidelity and integrity of data recovery. It is understandable that through programmatic implementation, the efficient operation of the data storage method in a practical system can be ensured.

[0129] Furthermore, the program design also considers exception handling and fault tolerance mechanisms. For example, during data writing, if irreversible deformation of the media surface or data corruption is detected, the program will automatically activate a redundant backup mechanism to ensure data integrity. It is important to understand that robust exception handling and fault tolerance mechanisms can improve the practicality of data storage. Through this embodiment, the computer program design ensures the efficient operation of the data storage method in a real-world system.

[0130] Although the present invention has been specifically described above with reference to preferred embodiments, it should be understood that the present invention is not limited to the embodiments described above. Various modifications and variations can be made by those skilled in the art without departing from the spirit of the present invention, and such modifications and variations should fall within the scope defined by the appended claims and their equivalents.

Claims

1. A data storage method based on optical coherence tomography, characterized in that, The data storage method includes the following steps: The raw data stream to be stored is converted into an optical modulation signal with depth dimension through a three-dimensional encoding module. The three-dimensional encoding module maps binary data into a multi-layer phase-amplitude composite encoding matrix based on a non-uniform sampling algorithm, wherein the spatial resolution of each layer matches the axial scanning accuracy of optical coherence tomography. A broadband, low-coherence beam is generated using a tunable laser source. The optical modulation signal is written into a predetermined depth position of the optical storage medium through a spatial light modulator and a dynamic focusing lens group. The writing process adopts a multi-focus parallel scanning strategy to ensure that the interval between adjacent data layers is less than the depth of field range of the optical system. During the data reading stage, the optical storage medium is scanned by an optical coherence tomography system. Interference signals are collected simultaneously and the scattering intensity distribution and phase delay information of each data layer are demodulated. The optical path difference of the reference arm is dynamically compensated according to the refractive index distribution of the storage medium. An adaptive noise suppression algorithm is used to reconstruct the interference signal in multiple dimensions, eliminating interlayer crosstalk and internal scattering noise of the medium, and generating a high-fidelity three-dimensional data matrix. The three-dimensional data matrix is ​​converted into a recovery data stream by a quantum error correction decoder. The decoder dynamically corrects the bit error rate based on the topological correlation of adjacent data blocks and uses a deep belief network to verify data integrity for reliable recovery. The step of mapping binary data into a multi-layer phase-amplitude composite coding matrix based on a non-uniform sampling algorithm includes: The original data stream is divided into a sequence of frames of length L, and a discrete wavelet transform is performed on each frame to generate a high-frequency component H and a low-frequency component L. The high-frequency component H is nonlinearly compressed and encoded to obtain the high-frequency component H', which is expressed as: Where σ is the noise threshold, R is the cutoff frequency radius, γ is the shape adjustment factor, and H(u,v) is the complex value of the original high-frequency component at the frequency domain coordinate (u, v). The high-frequency component H' and the low-frequency component L are superimposed with weights α and β to generate a composite coding matrix C: Wherein, α and β control the contribution ratios of the low-frequency component L and the high-frequency component H' in the composite coding matrix, respectively, satisfying α 2 +β 2 = 1 to maintain energy conservation; The composite coding matrix is ​​allocated to the N axial layers of the optical storage medium using a depth mapping function, which is: Where z0 is the reference depth, n represents the layer number, and var(C n ) represents the variance of the nth layer matrix, and Δz represents the baseline interlayer spacing.

2. The data storage method based on optical coherence tomography as described in claim 1, characterized in that, The implementation steps of the multi-focus parallel scanning strategy include: Calculate the phase compensation function of the spatial light modulator based on the depth distribution of the target data layer: Where λ is the wavelength of the light source, (x, y, z) is the focal position, (x0, y0, z0) is the focal reference position, and ∇ 2 Let T(x,y,z) be the Laplace operator, T(x,y,z) be the temperature field of the medium, and η be the thermal distortion compensation coefficient. Set the scanning path to meet the optimal motion trajectory time condition for multiple focal points: , where t k Let μ be the dwell time of the k-th focus, K be the total number of focuses, and μ be the path weight factor. The constraint is that the distance between adjacent focuses is greater than the diffraction-limited distance. k ,y k Let be the target position coordinates of the k-th focus in the horizontal plane, k∈[1,K], (x k-1 , y k-1 ): The coordinates of the previous position of the (k-1)th focus in the horizontal plane, used to calculate the Euclidean distance of the focus movement.

3. The data storage method based on optical coherence tomography as described in claim 1, characterized in that, The dynamic correction rule of the quantum error correction decoder is as follows: Detect the amplitude A and phase φ of the current data block. If the following conditions are met: Then it is determined to be a modulation symbol. Where i is the imaginary unit, δ is the initial decision threshold, and BER t This represents the current bit error rate. Update the threshold based on the correlation between adjacent data blocks: Where ξ is the learning rate, σ is the smoothing factor, and BER target To set a bit error rate limit.

4. The data storage method based on optical coherence tomography as described in claim 1, characterized in that, The optical storage medium comprises alternating high-refractive-index photonic crystal layers and low-refractive-index spacer layers. The periodic structure bandgap wavelength of the photonic crystal layers is matched with the center wavelength of the writing laser to enhance the signal-to-noise ratio of the data layers. The thickness of the spacer layer is set according to the axial resolution of optical coherence tomography to ensure that the minimum spacing between adjacent data layers is less than 1 / 2 of the system depth of field. The surface of the medium is covered with an anti-reflective coating and a hard protective layer, the protective layer being made of diamond-like carbon material with a thickness of 50-100 nanometers, to balance optical transmittance and mechanical abrasion resistance.

5. The data storage method based on optical coherence tomography as described in claim 1, characterized in that, The steps of the multi-focus parallel scanning strategy include: A reference marker array is generated on the surface of the medium using a low-power probe beam, and the initial coordinates of each marker are recorded. During data writing, a probe beam is periodically emitted to detect the position offset of the reference mark. If the offset exceeds the preset tolerance, the phase correction module of the spatial light modulator is triggered to realign the scan path. After the data writing is completed, the reference marker is holographically verified. If irreversible deformation is found, the corresponding data area is marked as an unreliable storage area and a redundant backup mechanism is initiated.

6. The data storage method based on optical coherence tomography as described in claim 1, characterized in that, When generating the composite encoding matrix, the three-dimensional encoding module embeds multiple layers of redundant error correction data, including: Reed-Solomon error correction codes are added to the edge regions of each layer of the data matrix, with an error correction capacity of 15%-20% of the original data block; A holographic verification layer is inserted every K layers along the axial depth direction. The verification layer contains a hash digest and parity check bit of the data from the adjacent K layers. During the data recovery phase, the verification layer information is parsed first. If local data corruption is detected, cross-layer data repair is performed according to the redundancy coding rules.

7. The data storage method based on optical coherence tomography as described in claim 6, characterized in that, During the writing process, the local temperature distribution of the optical storage medium is monitored in real time, and the laser power and focal position are dynamically adjusted according to the thermal expansion effect. The steps include: Real-time temperature data of each data layer is collected by a distributed temperature sensor array integrated on the surface of the storage medium. Based on the temperature dependence of the thermal expansion coefficient and refractive index of the medium, the focal point drift caused by the thermal lensing effect is calculated, and the focal point position is compensated by a dynamic focusing lens group. Based on the preset power-temperature response curve, the output power of the tunable laser source is adjusted in a closed-loop control manner to stabilize the writing energy within the thermal saturation threshold of the medium, thereby avoiding material phase change or optical damage.

8. A data storage system based on optical coherence tomography, used to implement the data storage method as described in any one of claims 1-7, characterized in that, The data storage system includes: A three-dimensional encoding module is used to convert the raw data stream into a multi-layer phase-amplitude composite encoding matrix; A tunable laser source and spatial light modulator assembly are configured to generate a multifocal scanning beam and write it into an optical storage medium. The tomographic scanning module, including a low-coherence interferometer and a dynamic optical path compensator, is used to acquire tomographic interference signals; The signal processing module is used to execute adaptive noise suppression algorithms and 3D data reconstruction; A quantum error correction decoder, based on a deep belief network, is used to achieve data recovery and integrity verification. The spatial light modulator group includes a liquid crystal phase modulator and a micromirror array, and its response time τ satisfies: Where Δz is the interlayer spacing, f is the refractive index of the medium, c is the speed of light, and NA is the numerical aperture of the objective lens.

9. A data storage device storing a computer program, characterized in that, When the program is executed by the processor, it implements the data storage method based on optical coherence tomography as described in any one of claims 1-7.

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