Vector distortion adaptive correction method and device based on polarization decomposition

Abstract

The invention discloses a vector distortion adaptive correction method and device based on polarization decomposition, and belongs to the technical field of optical measurement. An incident light field is divided into two orthogonal polarization components, a traditional wavefront sensor and a wavefront corrector are partitioned, and phase distortion of the two polarization components is measured and corrected by introducing polarization decomposition. According to the method, only the phase distortion of two polarization components is measured and corrected by using the relationship between the phase distortion and the polarization distortion, and when the phase distortion of the two polarization components is effectively compensated, the corresponding polarization distortion can be naturally compensated, so that the synchronous correction of the phase distortion and the polarization distortion is synchronously realized; a brand new idea is provided for developing a vector adaptive optical technology.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical measurement, and more specifically, relates to a vector distortion adaptive correction method and device based on polarization decomposition. Background Art

[0002] Adaptive Optics (AO) is a key technology for compensating wavefront distortion caused by medium perturbation during the propagation of light waves, and is widely used in fields such as high-resolution imaging, precision laser focusing, and long-distance optical detection. Its core goal is to improve the spatial resolution and light energy concentration of the system by dynamically adjusting the wavefront morphology, thereby improving image quality and signal stability. Especially in complex propagation environments with strong scattering or refractive index fluctuations, adaptive optics technology can effectively suppress the influence of wavefront distortion on system performance, showing prominent application advantages. However, traditional adaptive optics technology is mostly based on a scalar light field model, mainly for sensing and compensating phase distortion, without considering the changes in the polarization dimension of light waves. With the continuous improvement of optical systems in terms of resolution, precision, and functionality, the requirements for light field control in the system have expanded from single-phase regulation to comprehensive regulation of vector characteristics such as polarization state. In applications such as high numerical aperture microscopy imaging, nonlinear optical processes, polarization multiplexing communication, and complex light-matter interaction regulation, polarization distortion often coexists with phase distortion and is mutually coupled. If polarization distortion is not effectively compensated, it will significantly affect the focus quality, imaging contrast, and system stability, becoming a key factor restricting the further development of traditional adaptive optics technology.

[0003] To solve the above problems, a new type of adaptive optics technology, namely Vectorial Adaptive Optics (V-AO), has been developed in recent years. Based on the traditional adaptive optics that only senses and compensates for phase distortion, this technology further introduces the dynamic sensing and regulation of the spatial distribution of polarization states to achieve the joint compensation of vectorial distortions (i.e., phase distortion and polarization distortion). By synchronously restoring the phase structure and polarization state consistency of light waves, vectorial adaptive optics significantly enhances the control ability of vectorial light fields and improves the sensing and correction effects in complex optical applications such as high-resolution imaging, vector beam shaping, and polarization contrast enhancement. However, existing vectorial adaptive optics systems mostly adopt the separate sensing and correction ideas for phase and polarization. For example, methods such as Stokes parameter reconstruction are used to first obtain the polarization state distribution of the light field and compensate for polarization distortion, and then the traditional wavefront sensors and correctors are used to complete the compensation of phase distortion. Although such schemes can achieve the joint compensation of phase and polarization, due to the independent polarization and phase sensing links, usually two sets of sensing and correction modules are required, resulting in a complex system structure and low integration, which are difficult to meet the requirements of high integration and miniaturization applications. In addition, compared with phase distortion sensing technology, the real-time sensing method for polarization distortion is still immature, especially lacking a scheme that can achieve single-frame polarization sensing to reduce the error accumulation and time-consuming problems caused by multi-frame polarization distortion measurement using the traditional Stokes parameter method.

[0004] In summary, compared with traditional adaptive optics systems, vectorial adaptive optics systems can correct both the phase and polarization distortions of light fields simultaneously and have broad application prospects. However, the vectorial adaptive optics technology currently mostly stays in the simple superposition of phase distortion correction and polarization distortion correction systems, lacking a mature integrated vectorial distortion sensing and correction method, and having many problems such as complex system structure and high cost. Therefore, it is urgent to develop a new type of vectorial adaptive optics architecture and method with a compact structure and develop an integrated vectorial distortion sensing and correction technology to promote the practical application process of vectorial adaptive optics technology. Summary of the Invention

[0005] Aiming at the defects of the prior art, the purpose of the present invention is to provide a vectorial distortion adaptive correction method and device based on polarization decomposition, aiming to solve the problems of complex optical path configuration, multi-step measurement, and the mutual coupling interference between polarization distortion and phase distortion in existing vectorial adaptive optics.

[0006] To achieve the above purpose, on the one hand, the present invention provides a vectorial distortion adaptive correction method based on polarization decomposition, including the following steps:

[0007] Decompose the incident light beam into a first polarization component and a second polarization component with orthogonal polarization directions;

[0008] Obtain the phase distortions of the first polarization component and the second polarization component; respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component.

[0009] Obtain again the phase distortions of the first polarization component and the second polarization component after loading the conjugates of the phase distortions, and respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component, forming a cyclic adaptive closed-loop correction process until a set correction threshold is reached, thereby realizing the compensation for the phase distortions of the first polarization component and the second polarization component.

[0010] When the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, realizing the synchronous correction of the polarization distortion and the phase distortion.

[0011] Combine the corrected first polarization component and the second polarization component to output the target beam.

[0012] On the other hand, the present invention provides a vector distortion adaptive correction method based on polarization decomposition, in which the compensation process does not adopt a continuous closed-loop feedback mode, but is updated according to an external trigger signal or by judging whether the change in the phase distortion reaches a threshold based on the result of the previous phase distortion measurement. This method is an open-loop mode and includes the following steps:

[0013] Decompose the incident beam into a first polarization component and a second polarization component with orthogonal polarization directions.

[0014] Respectively obtain the phase distortions of the first polarization component and the second polarization component; respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component to realize the compensation for the phase distortions of the first polarization component and the second polarization component.

[0015] When the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, realizing the synchronous correction of the polarization distortion and the phase distortion.

[0016] Combine the corrected first polarization component and the second polarization component to output the target beam.

[0017] On yet another aspect, the present invention provides a vector distortion adaptive correction device based on polarization decomposition, including a polarization decomposer, a phase corrector, a phase sensor, a controller, and a polarization combiner.

[0018] The polarization decomposer is used to decompose the incident beam into a first polarization component and a second polarization component with orthogonal polarization directions.

[0019] The phase sensor is used to obtain the phase distortions of the first polarization component and the second polarization component.

[0020] The controller is used to control the phase corrector to respectively load the conjugates of the respective phase distortions of the first polarization component and the second polarization component, so as to compensate for the phase distortions of the first polarization component and the second polarization component, and to compensate for the phase distortions of the first polarization component and the second polarization component; when the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, synchronous correction of the polarization distortion and the phase distortion is achieved;

[0021] The corrected first polarization component and second polarization component are combined by the polarization beam combiner and then output as a target beam.

[0022] Further preferably, a non-polarizing beam splitter is further included. The incident beam is decomposed by the polarization decomposer into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are transmitted to the non-polarizing beam splitter and divided into two paths. One path is directly output, and the other path is incident on the phase sensor for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller is used to control the phase corrector to respectively load the conjugates of the respective phase distortions of the first polarization component and the second polarization component. After the first polarization component and the second polarization component are corrected by the phase corrector, they are transmitted to the non-polarizing beam splitter again and divided into two paths. One path is used to obtain the phase distortions of the first polarization component and the second polarization component again, and to respectively load the conjugates of the respective phase distortions of the first polarization component and the second polarization component, forming an adaptive closed-loop correction process that repeats until the correction requirement threshold is reached. The directly output path is combined by the polarization beam combiner and output as a target beam.

[0023] Further preferably, a non-polarizing beam splitter is further included. The incident light is decomposed by the polarization decomposer into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are divided into two paths by the non-polarizing beam splitter. One path is incident on the phase corrector, and the other path is incident on the phase sensor for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller is used to control the phase corrector to respectively load the conjugates of the respective phase distortions of the first polarization component and the second polarization component. The conjugate information of the phase distortion loaded by the corrector can be updated when triggered by an external signal or when it is determined whether the polarization state change reaches the threshold according to the polarization state of the previous measurement result. An open-loop mode correction process is formed. The corrected first polarization component and second polarization component are combined by the polarization beam combiner and output as a target beam.

[0024] Further preferably, it further includes a non-polarizing beam splitter and a second polarizer. The incident beam is decomposed by a polarization decomposer into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are transmitted to a polarization combiner to obtain a combined beam. The combined beam is split into two paths by the non-polarizing beam splitter. One path is directly output, and the other path is incident on the second polarizer and decomposed again into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are incident on a phase sensor for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller is used to control the phase corrector to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component. The first polarization component and the second polarization component decomposed by the polarization decomposer are corrected by the phase corrector and then transmitted to the polarization combiner again for combining to obtain a combined beam. The combined beam is split into two paths by the non-polarizing beam splitter. One path is used to obtain the phase distortions of the first polarization component and the second polarization component again, and to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component, forming a cyclic adaptive closed-loop correction process until the correction requirement threshold is reached; the directly output path outputs the target beam.

[0025] Further preferably, it further includes a non-polarizing beam splitter, a first half-wave plate, and a second half-wave plate. The phase corrector is a polarization-dependent phase corrector; the incident beam is decomposed by a polarization decomposer into a first polarization component and a second polarization component with orthogonal polarization directions. The polarization direction of the first polarization component is adjusted by the first half-wave plate so that the first polarization component and the second polarization component have the same polarization direction, and both polarization directions are consistent with the working polarization direction of the polarization-dependent phase corrector. Then, it is reflected by the plane reflection surface of the phase corrector together with the second polarization component. The polarization direction of the first polarization component is changed by the second half-wave plate to make it orthogonal to the polarization direction of the second polarization component. Then, it is split into two paths by the non-polarizing beam splitter together with the second polarization component. One path is directly output, and the other path is incident on a phase sensor for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller is used to control the phase corrector to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component. After the first polarization component and the second polarization component with the same polarization direction are corrected by the phase corrector, the polarization direction of the first polarization component is changed by the second half-wave plate to make it orthogonal to the polarization direction of the second polarization component. Then, it is split into two paths again by the non-polarizing beam splitter together with the second polarization component. The directly output path is combined by a polarization combiner to output the target beam.

[0026] Furthermore, the difference in the phase distortion between the first polarization component and the second polarization component is polarization distortion. By calculating the difference in the phase distortion of the two polarization components, polarization distortion information can be obtained, realizing the synchronous sensing of phase distortion and polarization distortion. When the phase distortions of the two polarization components reach the compensation effect, the two polarization components have an approximately planar phase distribution, and the phase difference between the two polarization components also approximately has a planar phase distribution, which means there is a uniform polarization state, thus realizing the synchronous correction of phase distortion and polarization distortion.

[0027] More preferably, the polarization decomposer is a beam displacer or other optical devices capable of realizing polarization decomposition.

[0028] In addition, the present invention also provides a vector distortion sensing device based on polarization decomposition, which can be used independently as an independent device, including a polarization decomposer and a phase sensor. This device is not a limitation on the methods and devices provided above. The polarization decomposer can specifically be a beam displacer, which divides the incident light beam into two polarization components that propagate parallel in space and are orthogonally polarized. However, the beam displacer is not a limitation on the polarization decomposer. It is only that the orthogonally polarized light emerging from the beam displacer propagates parallel in space, which is convenient for the implementation of the methods and devices of this patent. The two polarization components are incident on different spatial regions of the phase sensor, and the phase distortion information of the two polarization components can be measured respectively. According to the phase distortion information of the two polarization components, polarization distortion information can also be obtained, that is, the synchronous sensing of phase distortion and polarization distortion can be realized based on single-frame data.

[0029] Through the above technical solutions conceived by the present invention, compared with the prior art, the following

[0030] beneficial effects can be achieved:

[0031] (1) The present invention provides a vector distortion adaptive correction method based on polarization decomposition, which divides the incident light field into two orthogonally polarized components, partitions the traditional wavefront sensor and the wavefront corrector respectively, and measures and corrects the phase distortion of the two polarization components respectively by introducing polarization decomposition. Utilizing the relationship between phase distortion and polarization distortion, only the phase distortion of the two polarization components is measured and corrected. When the phase distortions of the two polarization components are effectively compensated, the corresponding polarization distortion can naturally be compensated, thereby synchronously realizing the synchronous correction of phase distortion and polarization distortion, which provides a brand-new idea for the development of vector adaptive optics technology.

[0032] (2) Different from the polarization and phase discrete sensing and correction methods commonly used in existing vector adaptive optical systems, the method of the present invention does not require a separate polarization sensing and correction module. Based only on the phase distortion information of two orthogonal polarization components, it can achieve synchronous sensing and compensation of vector distortion. Compared with the traditional scheme, the present invention has the following significant advantages:

[0033] ① It avoids the use of additional polarization sensing devices, simplifies the optical path configuration, and makes the overall system more compact and efficient;

[0034] ② Adopting a single-frame measurement method, it can simultaneously obtain the phase and polarization distortion information of two polarization components within a single exposure, avoiding error accumulation and system instability caused by multiple measurements;

[0035] ③ Through polarization decomposition, the decoupling of polarization distortion and phase distortion is achieved, and the correction in two dimensions is simplified to one-dimensional correction of the phase distortion of two polarization components.

[0036] ④ The overall system has a higher integration level and better stability, and is more suitable for the application requirements of miniaturized and practical vector adaptive optics.

[0037] (3) The vector adaptive optical technology of the present invention can be widely applied to many important technical fields such as polarization imaging, laser communication, and precision microscopic imaging, and has great practical value and market potential.

[0038] (4) The implementation idea of the present invention can also contribute to the research and development of vector wavefront detectors and correctors that can be used independently. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic flow chart of a vector distortion adaptive correction method based on polarization decomposition provided by the present invention.

[0040] Figure 2 It is a schematic flow chart of a vector distortion correction method based on polarization decomposition provided by the present invention.

[0041] Figure 3 It is a schematic diagram of the closed-loop mode structure of a vector distortion adaptive correction device based on polarization decomposition provided by the present invention.

[0042] Figure 4 It is a schematic diagram of the open-loop mode structure of a vector distortion adaptive correction device based on polarization decomposition provided by the present invention.

[0043] Figure 5 It is another schematic diagram of the closed-loop mode structure of a vector distortion adaptive correction device based on polarization decomposition provided by the present invention.

[0044] Figure 6 For Figure 3Schematic structural diagram of the structure using a polarization - related phase corrector.

[0045] Figure 7 This is the schematic structural diagram of the dual - polarization distortion measurement device (which can be used independently as a vector distortion sensor) provided by the present invention.

[0046] Figure 8 Based on Figure 6 The schematic structural diagram of the device in the embodiment. A laser, a focusing lens, and a camera are added on this basis.

[0047] Figure 9 For the phase distortion measurement results, polarization distribution of the polarization - combined beam, and lens focusing situation in two cases before and after correction in the presence of polarization distortion and phase distortion in the embodiment; before correction, (a) and (b) are the phase distortions of the two measured polarization components; (c) is the polarization ellipse calculated based on the measured phase distortion; (d) is the lens focusing situation under polarization distortion and phase distortion; after correction, (e) and (f) are the phase distortions of the two measured polarization components; (g) is the polarization ellipse calculated based on the measured phase distortion; (h) is the lens focusing situation after correction. Detailed implementation manners

[0048] In order to make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] The present invention provides a vector distortion adaptive correction method based on polarization decomposition, as Figure 1 shown, which includes the following steps:

[0050] Decompose the incident light beam into a first polarization component and a second polarization component with orthogonal polarization directions;

[0051] Obtain the phase distortions of the first polarization component and the second polarization component; respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component;

[0052] Obtain the phase distortions of the first polarization component and the second polarization component after loading the conjugates of the phase distortions again, and respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component, forming an adaptive process of continuous correction until the correction requirement threshold is reached, so as to realize the compensation of the phase distortions of the first polarization component and the second polarization component;

[0053] When the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, synchronous correction of the polarization distortion and the phase distortion is achieved;

[0054] Combine the corrected first polarization component and the second polarization component to output a target beam.

[0055] The present invention also provides a vector distortion correction method based on polarization decomposition, as Figure 2 shown, including the following steps:

[0056] Decompose the incident beam into a first polarization component and a second polarization component with orthogonal polarization directions;

[0057] Obtain the phase distortions of the first polarization component and the second polarization component; respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component to achieve compensation for the phase distortions of the first polarization component and the second polarization component; when the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, synchronous correction of the polarization distortion and the phase distortion is achieved;

[0058] Combine the corrected first polarization component and the second polarization component to output a target beam.

[0059] The present invention also provides a vector distortion adaptive correction device based on polarization decomposition, including a polarization decomposer 1, a phase corrector 2, a phase sensor 4, a controller 5, and a polarization combiner 6;

[0060] The polarization decomposer 1 is used to decompose the incident beam into a first polarization component and a second polarization component with orthogonal polarization directions;

[0061] The phase sensor 4 is used to obtain the phase distortions of the first polarization component and the second polarization component;

[0062] The controller 5 is used to control the phase corrector 2 to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component to achieve compensation for the phase distortions and polarization distortions of the first polarization component and the second polarization component; when the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, synchronous correction of the polarization distortion and the phase distortion is achieved;

[0063] The corrected first polarization component and the second polarization component are combined after passing through the polarization combiner 6 to output a target beam.

[0064] Among them, the relative relationship between the phase sensor 4 and other components can be adjusted by a beam splitter. Specific embodiments of several different positional relationships are given below.

[0065] Embodiment 1

[0066] As shown in Figure 3 Figure , the present invention provides an open-loop mode structure of a vector adaptive optical device based on polarization decomposition, further including an unpolarized beam splitter 3, which is located after the phase corrector 2. The specific implementation manner is as follows:

[0067] The device includes a polarization decomposer 1, a phase corrector 2, an unpolarized beam splitter 3, a phase sensor 4, a controller 5, and a polarization combiner 6. The incident beam first undergoes polarization decomposition by the polarization decomposer 1, dividing the beam into a first polarization component and a second polarization component. The phase corrector 2 is divided into two spatial regions to independently control the phases of these two polarized components. The two beams after regulation are combined and output through the polarization combiner 6. The unpolarized beam splitter 3 is arranged in the optical path to extract part of the optical power from the regulated optical path and send it to the subsequent phase sensor 4 for aberration measurement and correction information update. The phase sensor 4 is divided into two spatial regions to measure the phase aberration information of two orthogonal polarization components respectively, and feedback it to the phase corrector 2 by the controller 5 for correction, forming a real-time feedback loop and a closed-loop mode to achieve dynamic compensation. Further, the polarization aberration can be calculated based on the difference between the two phase aberrations, realizing the synchronous perception of phase aberration and polarization aberration. Specifically, the phase sensor 4 and the phase corrector 2 are connected to the controller 5 by signal lines. According to the dual-polarization aberration information measured by the phase sensor 4, two conjugate compensation phases can be generated and loaded onto the corresponding spatial positions of the phase corrector 2 to compensate for the phase aberration of the dual polarization. When the phase aberrations of the two polarization components are compensated, the polarization aberration is naturally compensated. The phase corrector 2, the phase sensor 4, the unpolarized beam splitter 3, and the controller 5 form a feedback loop to form a closed-loop mode, which can dynamically correct the vector aberration in real time. In this device, the beam after polarization decomposition and correction is transmitted to the phase sensor 4 before polarization combination output, and no additional decomposition step is required before the phase sensor 4.

[0068] Embodiment 2

[0069] As an improvement to the above technical solution of the device, the unpolarized beam splitter 3 can be located before the phase corrector 2. As shown in Figure 4 Figure , in this device, the beam after correction is directly combined and output, and will not enter the phase sensor 4 again for aberration measurement. At this time, the device operates in an open-loop mode. In the open-loop mode, the conjugate information of the phase aberration loaded on the corrector can be updated when triggered by an external signal or when it is determined whether the change in the phase aberration reaches a threshold according to the previous phase aberration measurement result.

[0070] Embodiment 3

[0071] As an improvement to the above technical solution of the device, the non-polarizing beam splitter 3 can be located after the output of the polarization beam combining 6. As Figure 5 shown, in this device, after the corrected light beam is directly combined and output, it enters the phase sensor 4 for aberration measurement. At this time, a polarization decomposer 7 needs to be added before the phase sensor 4 to perform the step of re-polarization decomposition. The above-mentioned device also belongs to a type of closed-loop mode.

[0072] In summary, the closed-loop mode extracts the measurement light after the phase corrector 2 through the non-polarizing beam splitter 3 to achieve dynamic feedback adjustment; while the open-loop mode extracts the measurement light before the phase corrector 2 and does not perform feedback after correction, which is suitable for application scenarios where the aberration state changes infrequently.

[0073] Embodiment 4

[0074] As an improvement to the above technical solution of the device, when the phase corrector 2 is a polarization-dependent phase corrector, a first half-wave plate 9 should be added to the transmission path of one of the polarized light beams after polarization decomposition to adjust the direction of this polarized light to be consistent with the working direction of the phase corrector 2. Further, a second half-wave plate 10 is added to one of the branches output from the phase corrector 2, and the angle of the second half-wave plate 10 is rotated so that the two light beams re-satisfy the orthogonal condition for polarization beam combining output. The polarization components of the functions of these two half-wave plates can be the same or different. In addition, when the phase corrector 2 is a reflective polarization-dependent phase corrector, a single half-wave plate can also be configured in the optical path. The configuration methods of this single half-wave plate include: at the intersection of the optical paths of different polarization components before and after the reflection of the phase corrector 2; or at the optical path covering the same polarization component before and after the reflection of the phase corrector 2. Both of these configurations can use a single half-wave plate to achieve polarization adjustment before and after reflection, reducing the number of devices used.

[0075] As Figure 6As shown in the figure, when the phase corrector adopts the polarization-dependent phase corrector 8, a half-wave plate needs to be configured for polarization state adjustment to match the working polarization direction of the polarization-dependent phase corrector 8. A first half-wave plate 9 is configured in front of the corrector to adjust the polarization direction of a certain polarization component of the incident light beam to make it consistent with the working polarization direction of the polarization-dependent phase corrector 8; a second half-wave plate 10 is configured behind the corrector to adjust the polarization direction of the outgoing polarization component to make it orthogonal to the other polarization component, so as to realize polarization beam combination. The polarization components affected by these two half-wave plates can be the same or different. Further, when the polarization-dependent phase corrector 8 is a reflective polarization-dependent phase corrector, only one half-wave plate can also be configured in the optical path to meet the polarization direction adjustment requirements and simplify the system. The configuration methods of this single half-wave plate include: at the intersection of the optical paths of different polarization components before and after the reflection of the corrector; or at the optical path covering the same polarization component before and after the reflection of the corrector. Both of these configurations can use one half-wave plate to realize the polarization adjustment before and after reflection, reducing the number of devices used.

[0076] As Figure 7 shown in the figure, the present invention also provides a dual-polarization distortion measurement device. When the phase corrector is not connected, this device can also be used as an independent vector distortion sensor unit to realize the vector distortion measurement of an external light beam. This device includes a polarization decomposer 7 and a phase sensor 4. It should be noted that the implementation method of the independent vector distortion sensor is not a limitation on the protection scope of the method and device of the present invention. The polarization decomposer 7 can specifically select a beam displacer. The beam displacer decomposes the incident light beam into two beams of orthogonally polarized light. These two beams of light propagate along spatially parallel paths and are respectively guided to different measurement regions of the phase sensor 4 for independent measurement. By calculating the phase difference from the measured phase distortion information of the two polarization components, the polarization distortion information is further deduced to realize the synchronous perception of phase distortion and polarization distortion.

[0077] The following introduces the specific embodiments of the vector adaptive optics based on polarization decomposition provided by the present invention to verify whether effective correction of polarization distortion and phase distortion can be achieved. The specific structure is as follows:

[0078] As Figure 8As shown, the experimental setup includes a polarization decomposer 1, a first half-wave plate 9, a polarization-dependent phase corrector 8, a second half-wave plate 10, an unpolarized beam splitter 3, a phase sensor 4, a controller 5, a polarization beam combiner 6, a laser 11, a focusing lens 12, and a camera 13. The laser 11 provides a stable laser source. A focusing lens 12 with a known focal length is added to the output optical path to observe the focusing conditions of the beam before and after correction at its focal plane. The camera 13 is used to record the focused spot at the rear focal plane of the lens 12. During the experiment, different distortion phase maps with a preset peak-to-valley ratio of 1.5λ are respectively loaded onto different regions corresponding to two polarization orthogonal components on the polarization-dependent phase corrector 8 to simulate vector distortion. The phase sensor 4 measures the phase distortion information of these two orthogonally polarized components and feeds it back to the polarization-dependent phase corrector 8 through the controller 5 for correction.

[0079] Figure 9 Shows the measurement results in two cases before and after correction in the experiment in the presence of polarization distortion and phase distortion. Before correction, (a) and (b) are the measured phase distortions of the two polarization components. The RMS (root mean square) of the X polarization = 0.185λ, PV (peak-to-valley ratio) = 1.484λ, the RMS of the Y polarization = 0.196λ, PV = 1.609λ; (c) is the polarization ellipse calculated based on the measured phase distortion, and the polarization distribution is chaotic; (d) is the focusing condition in the presence of distortion, and the spot is diffused. After correction, (e) and (f) are the phase distortions of the two polarization components. The RMS of the X polarization = 0.032λ, PV = 0.215λ, the RMS of the Y polarization = 0.027λ, PV = 0.159λ; (g) is the polarization ellipse after correction, and the polarization distribution is uniform; (h) is the focusing condition, and the energy is concentrated. After correction, the phases of the two polarization components tend to be flat, and the phase difference between them is also close to flat, indicating that both polarization distortion and phase distortion are effectively compensated. The focusing intensity is increased by about 113%, the spot profile is close to the Gaussian distribution, and the polarization consistency is improved synchronously.

[0080] It is easy for those skilled in the art to understand that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A vector distortion adaptive correction method based on polarization decomposition, characterized in that Including the following steps: Decompose the incident light beam into a first polarization component and a second polarization component with orthogonal polarization directions; Obtain the phase distortions of the first polarization component and the second polarization component; respectively load the conjugates of their respective phase distortions onto the first polarization component and the second polarization component; Obtain again the phase distortions of the first polarization component and the second polarization component after loading the conjugates of the phase distortions, and respectively load the conjugates of their respective phase distortions onto the first polarization component and the second polarization component, forming a cyclic adaptive closed-loop correction process until a set correction threshold is reached, so as to realize the compensation for the phase distortions of the first polarization component and the second polarization component; when the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, realizing the synchronous correction of the polarization distortion and the phase distortion; Combine the corrected first polarization component and the second polarization component, and output the target light beam.

2. A vector distortion adaptive correction method based on polarization decomposition, characterized in that Including the following steps: Decompose the incident light beam into a first polarization component and a second polarization component with orthogonal polarization directions; Obtain the phase distortions of the first polarization component and the second polarization component; respectively load the conjugates of their respective phase distortions onto the first polarization component and the second polarization component, realizing the compensation for the phase distortions of the first polarization component and the second polarization component; when the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, realizing the synchronous correction of the polarization distortion and the phase distortion; Combine the corrected first polarization component and the second polarization component, and output the target light beam.

3. A vector distortion adaptive correction device based on polarization decomposition, characterized in that, Including a polarization decomposer (1), a phase corrector (2), a phase sensor (4), a controller (5) and a polarization combiner (6); The polarization decomposer (1) is used to decompose the incident light beam into a first polarization component and a second polarization component with orthogonal polarization directions; The phase sensor (4) is used to obtain the phase distortions of the first polarization component and the second polarization component; The controller (5) is used to control the phase corrector (2) to respectively load the conjugates of their respective phase distortions onto the first polarization component and the second polarization component, realizing the compensation for the phase distortions of the first polarization component and the second polarization component; when the phase distortions of the first polarization component and the second polarization component are compensated, it is equivalent to compensating for the polarization distortion, that is, realizing the synchronous correction of the polarization distortion and the phase distortion; The corrected first polarization component and the second polarization component are combined after passing through the polarization combiner (6), and the target light beam is output.

4. The device according to claim 3, characterized in that It further includes a non-polarizing beam splitter (3). The incident beam is decomposed by a polarization decomposer (1) into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are transmitted to the non-polarizing beam splitter (3) and divided into two paths. One path is directly output, and the other path is incident on a phase sensor (4) for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller (5) is used to control the phase corrector (2) to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component. After being corrected by the phase corrector (2), the first polarization component and the second polarization component are transmitted to the non-polarizing beam splitter (3) again and divided into two paths. One path is used to obtain the phase distortions of the first polarization component and the second polarization component after loading the conjugates of the phase distortions again, and the conjugates of their respective phase distortions are respectively loaded on the first polarization component and the second polarization component, forming a cyclic adaptive closed-loop correction process until a set correction threshold is reached; the directly output path is combined by a polarization combiner (6) to output a target beam.

5. The device according to claim 3, characterized in that, It further includes a non-polarizing beam splitter (3). The incident light is decomposed by a polarization decomposer (1) into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are divided into two paths by the non-polarizing beam splitter (3). One path is incident on a phase corrector (2), and the other path is incident on a phase sensor (4) for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller (5) is used to control the phase corrector (2) to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component. After being corrected, the first polarization component and the second polarization component are combined by a polarization combiner (6) to output a target beam.

6. The device according to claim 3, characterized in that, It further includes an unpolarized beam splitter (3) and a second polarizer (7). The incident beam is decomposed by a polarization decomposer (1) into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are transmitted to a polarization combiner (6) to obtain a combined beam. The combined beam is split into two paths by the unpolarized beam splitter (3). One path is directly output, and the other path is incident on the second polarizer (7) and decomposed again into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component and the second polarization component are incident on a phase sensor (4) for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller (5) is used to control the phase corrector (2) to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component. The first polarization component and the second polarization component decomposed by the polarization decomposer (1) are corrected by the phase corrector (2) and then transmitted to the polarization combiner (6) again for combination to obtain a combined beam. The combined beam is split into two paths by the unpolarized beam splitter (3). One path is used to obtain the phase distortions of the first polarization component and the second polarization component after loading the conjugates of the phase distortions respectively, and the conjugates of their respective phase distortions are respectively loaded on the first polarization component and the second polarization component, forming a cyclic adaptive closed-loop correction process until the correction requirement threshold is reached; the directly output path outputs the target beam.

7. The device according to claim 3, characterized in that, It further includes an unpolarized beam splitter (3), a first half-wave plate (9), and a second half-wave plate (10). The phase corrector (2) is a polarization-dependent phase corrector. The incident beam is decomposed by a polarization decomposer (1) into a first polarization component and a second polarization component with orthogonal polarization directions. The first polarization component changes its polarization direction through the first half-wave plate (9) to make its polarization direction the same as that of the second polarization component, and then is reflected by the phase corrector (2) together with the second polarization component. The first polarization component then changes its polarization direction through the second half-wave plate (10) to make its polarization direction orthogonal to that of the second polarization component, and then is split into two paths by the unpolarized beam splitter (3) together with the second polarization component. One path is directly output, and the other path is incident on a phase sensor (4) for phase distortion measurement to obtain the phase distortions of the first polarization component and the second polarization component. The controller (5) is used to control the phase corrector (2) to respectively load the conjugates of their respective phase distortions on the first polarization component and the second polarization component. After the first polarization component and the second polarization component with the same polarization direction are corrected by the phase corrector (2), the first polarization component then changes its polarization direction through the second half-wave plate (10) to make its polarization direction orthogonal to that of the second polarization component, and then is split into two paths again by the unpolarized beam splitter (3) together with the second polarization component. The directly output path is combined by the polarization combiner (6) to output the target beam.

8. The device according to any one of claims 4-7, characterized in that The difference between the phase distortions of the first polarization component and the second polarization component is polarization distortion. The correction of polarization distortion is completed while the phase distortion correction is completed.

9. The device according to claim 3, characterized in that, The polarization decomposer (1) is a beam displacer.

10. A vector distortion sensing device based on polarization decomposition, characterized in that, It includes: A polarization decomposer for decomposing an incident light beam into a first polarization component and a second polarization component with orthogonal polarization directions; A phase sensor for respectively obtaining the phase distortion information of the first polarization component and the second polarization component; and obtaining polarization distortion information by taking the difference according to the phase distortion information, so as to realize the synchronous perception of phase distortion and polarization distortion.

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