An optical system polarization aberration compensation method, computer equipment and storage medium

Abstract

The present application relates to the technical field of optical design, and particularly provides an optical system polarization aberration compensation method, a computer device and a storage medium, at least one plane mirror is added in the optical system to be compensated, the plane mirror is arranged before an image plane of the optical system, and a spatial pose of each plane mirror is taken as a free variable, the spatial pose of each plane mirror is adjusted in a selectable range of the spatial pose of the plane mirror, the spatial pose of the plane mirror is iteratively optimized, polarization aberration of the compensated optical system meets preset requirements, and the polarization aberration of the optical system is greatly reduced under the premise that the wave aberration of the optical system is not changed and no design freedom is occupied.

Description

Technical Field

[0001] The present invention belongs to the technical field of optical design, and in particular relates to a polarization aberration compensation method for an optical system, a computer device, and a storage medium. Background Art

[0002] Like wavefront aberration and optical efficiency, polarization aberration is a fundamental property of optical systems. Polarization aberration in optical systems alters the polarization state of incident light, thereby affecting image quality and detection accuracy. For high-end optical instruments such as astronomical telescopes and photolithography objectives, polarization aberration is a crucial factor in determining system performance. Therefore, suppressing polarization aberration in optical systems is a key to achieving high-performance modern optical systems.

[0003] Optical structure optimization design is an important method for suppressing polarization aberration in optical systems. By optimizing the structural parameters of the optical system, an optical system with both high imaging quality and low polarization aberration can be obtained. However, this design method imposes additional constraints on the system's polarization aberration, occupying the design freedom that could be used to optimize the optical system's shape constraints, image telecentricity, and other factors. This results in a certain gap between the design results and practical engineering applications.

[0004] Because plane mirrors have no optical power and can be machined to extremely high surface precision, their impact on the system's wavefront aberration is negligible. Plane mirrors can change the incident angle of light and thus manipulate the system's polarization aberration. Therefore, plane mirrors can separate the optimization tasks of wavefront aberration and polarization aberration in optical systems, which has significant engineering application value for suppressing polarization aberration. Therefore, the use of plane mirrors to compensate for polarization aberration in optical systems is of great significance.

[0005] However, current methods for suppressing polarization aberration using plane mirrors are generally limited to mutual compensation between plane mirrors, or between a plane mirror and a single optical element. Using plane mirrors to reduce polarization aberration in an entire optical system has not been thoroughly studied. Therefore, a method for compensating for polarization aberration in an entire optical system using plane mirrors is urgently needed. Summary of the Invention

[0006] In view of this, the present invention aims to provide a method for compensating polarization aberration of an optical system, a computer device and a storage medium, which can significantly reduce the polarization aberration of an optical system without changing the wavefront aberration of the optical system and without occupying the design freedom.

[0007] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0008] The present invention provides a method for compensating polarization aberration of an optical system, comprising: adding at least one plane reflector in the optical system, taking the spatial posture of each plane reflector as a free variable, and adjusting the spatial posture of each plane reflector so that the polarization aberration of the optical system meets a preset value.

[0009] Preferably, the polarization aberration of the optical system before compensation is decomposed into directional Zernike polynomials to calculate the spatial frequency of the polarization aberration distribution, and the number of additional plane mirrors is determined based on whether the polarization aberration of the optical system meets a preset value.

[0010] Preferably, the spatial posture of the plane mirror is expressed by its normal vector express.

[0011] Preferably, the normal vector The parameters are expressed as ,in, is the incident angle of the plane mirror in the spherical coordinate system, is the azimuth angle of the plane mirror in the spherical coordinate system.

[0012] Preferably, the adjusting the spatial posture of each plane reflector by taking the spatial posture of each plane reflector as a free variable comprises:

[0013] Based on the ray tracing data of the optical system, the central field of view main ray propagation vector and the edge ray propagation vector , and obtain the incident angle The value range of is:

[0014] ;

[0015] Azimuth The value range is ;

[0016] At the incident angle and azimuth In the range of values, the incident angle and azimuth Assigning values, generating a plane reflector after the assignment in the optical system, calculating the polarization aberration of the optical system after the plane reflector is added, and judging whether the polarization aberration of the optical system after the plane reflector is added meets a preset value.

[0017] Preferably, generating a plane reflector after the assignment in the optical system includes: and azimuth , calculate the normal vector of the plane mirror Direction cosines in global coordinates , and the direction cosines in the global coordinate system Converted to the plane mirror coordinate system of the initial state and expressed as , the z-axis of the plane mirror coordinate system in the initial state is parallel to the z-axis of the global coordinate system;

[0018] According to the direction cosines in the initial state coordinate system of the plane mirror , calculating the rotation angle of the plane reflector around the plane reflector coordinate system after the assigned value compared to the initial state, where the positive direction of the z-axis of the plane reflector coordinate system is the same as the direction of the normal vector of the plane reflector;

[0019] The rotation angle of the plane reflector around the plane reflector coordinate system is input into the optical design software to generate the assigned plane reflector.

[0020] Preferably, the polarization aberration of the optical system after the plane mirror is added is calculated by three-dimensional polarization ray tracing.

[0021] Preferably, the rotation angle of the plane reflector around the plane reflector coordinate system includes: a rotation angle of the plane reflector around the x-axis of the plane reflector coordinate system and a rotation angle of the plane reflector around the y-axis of the plane reflector coordinate system.

[0022] The present invention provides a computer device, comprising:

[0023] at least one processor; and

[0024] a memory communicatively connected to the at least one processor; wherein,

[0025] The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform a method for compensating for polarization aberration of an optical system.

[0026] The present invention provides a storage medium storing computer instructions, wherein the computer instructions are used to enable the computer to execute a method for compensating polarization aberration of an optical system.

[0027] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0028] The present invention proposes for the first time the use of a plane mirror to compensate for the polarization aberration of the entire optical system, overcoming the limitation of traditional compensation only between plane mirrors or between a plane mirror and a single optical element. By introducing a plane mirror in front of the image plane of the optical system, adjusting the spatial orientation angle of the mirror through an optimization algorithm, and taking the polarization aberration of the optical system as the optimization target, the optimization algorithm is used to regulate the distribution of light on the incident surface of each optical surface, thereby significantly reducing the polarization aberration of the system without changing the wavefront aberration of the optical system, thereby achieving compensation for the polarization aberration of the optical system.

[0029] During the polarization aberration compensation process of the optical system, the method of the present invention only uses a plane mirror, does not significantly increase the structural complexity of the optical system, and does not change the focal length, aperture, wavefront aberration and imaging quality of the original optical system at all. The polarization aberration optimization task is "stripped" from the main system design, avoiding the disadvantage of traditional methods that sacrifice design freedom such as shape and telecentricity in order to suppress polarization. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0031] Figure 1 is a flow chart of a method for compensating polarization aberration of an optical system provided by an embodiment of the present invention;

[0032] Figure 2 1 is a schematic diagram of a normal vector limitation range of a plane reflector provided in an embodiment of the present invention;

[0033] Figure 3 is a schematic diagram of an optical system without polarization aberration compensation according to an embodiment of the present invention;

[0034] Figure 4 is a schematic diagram of an optical system after polarization aberration compensation according to an embodiment of the present invention;

[0035] Figure 5 is a convergence curve diagram of an evaluation function during iterative optimization of a plane reflecting mirror provided by an embodiment of the present invention;

[0036] Figure 6 is a comparison diagram of the two-way attenuation between a reference system provided by an embodiment of the present invention and an optical system after polarization aberration compensation;

[0037] Figure 7 3 is a comparison diagram of phase delay between a reference system provided according to an embodiment of the present invention and an optical system after polarization aberration compensation.

[0038] Reference numerals include:

[0039] Primary mirror 1, secondary mirror 2, tertiary mirror 3, first plane reflector 4, second plane reflector 5, image plane 6. DETAILED DESCRIPTION

[0040] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention. Similar elements in different embodiments use associated similar element numbers. In the following embodiments, many detailed descriptions are intended to enable the present invention to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present invention are not shown or described in the specification. This is to avoid the core part of the present invention being overwhelmed by too much description. For those skilled in the art, it is not necessary to describe these related operations in detail. They can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0041] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other to form various implementation methods. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various orders in the description and the drawings are only for the purpose of clearly describing a certain embodiment and are not intended to be a required order, unless otherwise specified that a certain order must be followed.

[0042] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0043] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0044] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0045] See also Figure 1 In one embodiment of the present invention, a method for compensating polarization aberration of an optical system is provided. The method comprises adding at least one plane mirror in the optical path before the image plane of the optical system to be compensated. The spatial posture of each plane mirror is used as a free variable, and the spatial posture of each plane mirror is adjusted so that the polarization aberration of the compensated optical system meets a preset value. Specifically, the method comprises the following steps:

[0046] S1: First, according to the structure and requirements of the optical system, the distribution of the polarization aberration of the original system is analyzed by three-dimensional polarization ray tracing, and the polarization aberration of the optical system before compensation is decomposed into directional Zernike polynomials to calculate the spatial frequency of the polarization aberration distribution. According to the spatial frequency of the polarization aberration distribution and the polarization aberration of the compensated optical system meeting the preset value, the number of plane reflectors to be introduced is determined. .

[0047] Specifically, the number of additional plane mirrors is determined based on the optical parameters of the optical system to be compensated and the preset values ​​of the polarization aberration. Due to differences in optical parameters such as system type, distribution and number of optical elements, and optical path form of different optical systems, the number of plane mirrors that need to be introduced may be different. For example, for a simple coaxial refraction system, a single plane mirror can usually be used for regulation and compensation, while for an off-axis reflection system, it is necessary to balance optical path asymmetry and occlusion issues, and generally at least two plane mirrors are required to achieve compensation. In addition, since there may be different requirements for the polarization aberration of the optical system during application, that is, the preset values ​​of the designed polarization aberration are different, this will also affect the number of plane mirrors introduced into the optical system. Under the premise of meeting the optical parameters and design requirements of the optical system, a smaller number n is preferably selected to reduce the complexity of the system and reduce the impact of the introduced plane mirrors on the original optical system.

[0048] S2: For each plane reflector introduced, select an appropriate expression method to represent each plane reflector.

[0049] Specifically, the normal vector of each plane reflector is used Indicates its corresponding spatial posture. In the embodiment of the present invention, the incident angle of the plane reflector in the spherical coordinate system is selected. and the azimuth of the plane mirror in the spherical coordinate system Determine the normal vector for each plane mirror , that is, the normal vector of each plane mirror is composed of a set of The only certainty. Figure 2 As shown, the incident angle of the plane mirror is is the angle between the normal vector of the plane reflector and the main ray of the central field of view of the system, which reflects the tilt of the plane reflector relative to the main ray. It is the angle between the projection of the normal vector of the plane reflector in the tangent plane of the principal ray and any reference axis in the plane, which reflects the rotation orientation of the plane reflector around the principal ray. is a free variable, representing the different spatial postures of the plane mirror. In terms of the representation, any parameter form that can effectively represent the normal vector of the plane mirror or completely describe its spatial posture can be selected as a free variable to be optimized.

[0050] If n plane mirrors are introduced into the optical system, each plane mirror involves two angle variables , so the number of free variables that need to be optimized is 2n.

[0051] S3: Based on the ray tracing data of the optical system, the central field of view main ray propagation vector is used and the edge ray propagation vector Determine the angle variable The value range of .

[0052] Specifically, due to the introduction of the plane reflector, when it is set to a certain angle, the plane reflector may be tilted at an improper angle, resulting in light being blocked and affecting the light transmission of the system. Therefore, it is necessary to adjust the two angle free variables. Make reasonable constraints. In the process of optimizing free variables, the following two situations should be avoided:

[0053] First, the incident angle of the plane mirror It should be larger than the angle between the marginal ray and the chief ray of the central field of view;

[0054] Second, the incident angle of the plane mirror It should be smaller than the angle between the normal corresponding to the edge ray and the main ray of the central field of view.

[0055] The maximum value range allowed for the normal vector of the plane reflector is limited to Figure 2 Consider using data communication between numerical calculation software (such as Matlab) and optical design software (such as CodeV) to extract the required marginal ray and main ray tracing data, and use the following formula to calculate the angle optimization free variable The value range of is:

[0056] ;

[0057] in, Indicates the angle of incidence The minimum value possible, Indicates the angle of incidence The maximum value possible.

[0058] Due to the azimuth It is determined by the projection of the normal vector on the tangent plane of the principal ray of the central field of view. Its value is not affected by the above angle constraints and ranges from 0 to 2π (unit: radians). In addition, when the actual optical system usually contains multiple fields of view, The value range of needs to be further limited according to the specific situation, and is located at ( , ), among which and The safety distance is limited by angle and can be flexibly set according to actual conditions.

[0059] S4: Angle of incidence and azimuth Perform random assignment.

[0060] Specifically, at the incident angle and azimuth Within the value range of , use random number generator or data calculation software such as Matlab to calculate the value of each group of free variables to be optimized. , generate the corresponding random number for assignment, that is, each plane mirror generates the corresponding angle optimization parameter.

[0061] S5: According to the assignment result, the tilt angle of the plane reflector is calculated, that is, the spatial posture of each plane reflector is determined.

[0062] Specifically, according to the incident angle assigned by the plane reflector and azimuth , calculate the normal vector of the plane mirror Representation in the global coordinate system, that is, calculating the normal vector Direction cosines in global coordinates , and then transform the direction cosines in the global coordinate system through the coordinate transformation matrix In the plane mirror coordinate system when converted to the initial state, the positive direction of the z-axis of the plane mirror coordinate system is the same as the direction of the normal vector of the plane mirror, and the xy plane coincides with the mirror surface of the plane mirror. The initial state refers to the state in which the normal vector of the plane mirror is parallel to the z-axis of the global coordinate system. The z-axis of the plane mirror coordinate system in the initial state is parallel to the z-axis of the global coordinate system. Therefore, the direction cosines in the global coordinate system are In the plane mirror coordinate system when converted to the initial state, it can be expressed as:

[0063] ;

[0064] in, The normal vector of the plane mirror in the plane mirror coordinate system represents the initial state, Represents the coordinate transformation matrix used for coordinate system transformation.

[0065] Further considering the rotation process of the plane reflector around the plane reflector coordinate system, the rotation angle of the plane reflector around the axis can be obtained, that is, the rotation angle of the plane reflector around the x-axis of the plane reflector coordinate system is and the rotation angle of the plane mirror around the y-axis of the plane mirror coordinate system :

[0066] ;

[0067] in, Represents the component of the normal vector in the x-axis direction, that is, the cosine of the angle with the x-axis, Represents the component of the normal vector in the y-axis direction, that is, the cosine of the angle with the y-axis, Represents the component of the normal vector in the z-axis direction, that is, the cosine of the angle with the z-axis.

[0068] By rotation angle and The tilt angle of the plane reflector can be determined, and the spatial position of the plane reflector can be directly controlled in the optical design software to optimize the spatial position of the plane reflector.

[0069] In the embodiment of the present invention, the global coordinate system is specified xyz The basis vectors are , , The normal vector of the plane mirror in its initial state is parallel to .like Figure 2 As shown, the center of the plane reflector is the intersection point A of the principal light and the plane reflector surface, and the normal vector of the plane reflector can be calculated using the Rodrigues rotation formula. Representation in the global coordinate system The specific calculation process is as follows:

[0070] Generate the initial state of the plane mirror in the optical design software and obtain the coordinates of point A A coordinate and the unit propagation vector of the principal ray K 0 and the unit propagation vector of the edge ray K 1. According to the geometric relationship, the coordinates of point B can be obtained :

[0071] .

[0072] Due to the azimuth It is relative to the reference axis and its value range is , so any straight line on the principal ray tangent plane can be selected as the reference axis. In the embodiment of the present invention, the reference axis Select as:

[0073] .

[0074] The reference axis Counterclockwise rotation around the chief ray Get the unit vector parallel to BC :

[0075] ;

[0076] Further combining the global coordinates of point A and point B, we can get the representation of the plane mirror normal vector in the global coordinate system after assignment, that is, the direction cosine :

[0077] ;

[0078] After obtaining the normal vector of the plane mirror after the assignment in the global coordinate system, the rotation angle of the plane mirror after the assignment compared to the initial state can be obtained, so as to realize the control of the spatial posture of the plane mirror in the optical design software.

[0079] Compared with the initial state, the rotation angle of the plane mirror around the plane mirror coordinate system can be calculated as follows:

[0080] The first method is to Convert to the plane mirror coordinate system in the initial state to describe the plane mirror orientation. Use optical design software to obtain the Euler angle of the plane mirror in the initial state relative to the global coordinate system , and combined with the rotation matrix around the global coordinate system , , , find the basis vectors of the plane mirror coordinate system , , :

[0081] ;

[0082] Basis vectors based on plane mirror coordinate system , , , construct the coordinate transformation matrix from the global coordinate system to the plane mirror coordinate system :

[0083] ;

[0084] Through the coordinate transformation matrix The normal vector Convert to the plane mirror coordinate system corresponding to the initial state, and combine Its representation in the plane mirror coordinate system can be obtained .

[0085] The second method is to calculate the rotation angle of the plane mirror around the x-axis and y-axis of its plane mirror coordinate system. and , the rotation matrix corresponding to this process is for:

[0086] ;

[0087] According to the above rotation relationship, the normal vector of the plane mirror in the initial state can be expressed as follows after transformation:

[0088] .

[0089] Since the normal vector of the plane mirror remains unchanged after rotation, only the description method changes, so the simultaneous expression Japanese style , we can get:

[0090] ;

[0091] Thus, the rotation angle of the plane mirror after assignment is calculated compared to the initial state and .

[0092] S6: Input the rotation angle of the plane reflector around the plane reflector coordinate system into the optical design software to generate an assigned plane reflector.

[0093] Specifically, data communication is established between the numerical calculation software and the optical design software. The numerical calculation software converts the rotation angle corresponding to the random assignment data into the value corresponding to the rotation angle according to the method described in step S5. and Input the input into the optical design software, and generate the assigned plane reflector in the optical system model in the optical design software, so that the spatial posture of the plane reflector is adjusted to the rotation angle calculated in step S5 and , a plane reflector having a specific orientation corresponding to the value assigned in step S4 is obtained. In the embodiment of the present invention, Matlab can be used as numerical calculation software, and CodeV can be used as optical design software.

[0094] S7: Calculate the polarization aberration of the optical system after adding the plane mirror, and construct a corresponding evaluation function.

[0095] Specifically, data communication between numerical calculation software and optical design software was used to calculate the system's polarization aberration, which includes bidirectional attenuation and phase delay, using a three-dimensional polarization ray tracing method. The polarization aberration of the optical system after adding a plane mirror was combined with the calculated polarization aberration, and a corresponding evaluation function was constructed based on the preset polarization aberration values ​​required by the optical system design.

[0096] S8: Using an optimization algorithm, iteratively calculate the spatial posture of each plane reflector until the polarization aberration of the optical system with the additional plane reflector meets a preset value.

[0097] Specifically, the evaluation function is used as an indicator and the incident angle is used as an indicator. and azimuth As a free variable, the incidence surface distribution of each optical surface can be regulated by a global optimization algorithm such as a genetic algorithm or a particle swarm optimization algorithm, and the optimization iteration of the plane mirror's spatial posture can be achieved. In each iteration, the polarization aberration of the optical system after the assignment is judged according to its evaluation function. If the polarization aberration of the optical system after the assignment meets the preset value, the optimization of the plane mirror's spatial posture is completed, and the polarization aberration of the optical system has been compensated to meet the design requirements; otherwise, the optimization of the plane mirror's spatial posture continues, and steps S3 to S8 are re-executed.

[0098] To verify the effectiveness of the method of the present invention, the compensation design of an off-axis three-mirror optical system is used as an example to illustrate the method.

[0099] First, if Figure 3As shown in Figure 1, an off-axis three-mirror optical system is designed as a reference system. The reference system includes a primary mirror 1, a secondary mirror 2, and a third mirror 3. The reference system is an off-axis three-mirror optical system with an F / 11 aperture of 100 mm and an effective field of view of 1°×1°. The structural parameters of the system are shown in Table 1. The RMS average value of the wavefront aberration of the effective field of view of the reference system is 0.021λ, and the polarization aberration calculation results are shown in Table 1. Figure 6 and Figure 7 As shown in the curve.

[0100] Table 1 Structural parameters of the reference system

[0101]

[0102] Based on the optical system polarization aberration compensation method proposed in the embodiment of the present invention, two plane mirrors are selected to compensate the polarization aberration of the reference system. Specifically, Figure 4 As shown, a first plane reflector 4 and a second plane reflector 5 are added to the optical path before the image plane 6 of the reference system, so that the spatial posture of the first plane reflector 4 and the second plane reflector 5 is As the free variables to be optimized, an evaluation function with two-way attenuation and phase delay as the target is constructed, and an iterative optimization algorithm is used to optimize the After 50 iterations of angle parameter search, the evaluation function is fully converged, and the compensation of the system polarization aberration is completed. The convergence curve of the evaluation function during the optimization iteration is as follows: Figure 5 shown.

[0103] Because the method of the present invention utilizes only plane mirrors and does not introduce other optical components, nor does it change the focal length, aperture, wavefront aberration, or imaging quality of the original system, the polarization aberration compensation process does not affect the original system's design parameters. Measurements show that the first-order parameters of the compensated optical system are identical to those of the reference system: F / 11, a clear aperture of 100 mm, and an effective field of view of 1° × 1°. The structural parameters of the compensated optical system are shown in Table 2.

[0104] Table 2 Structural parameters of the optical system after compensation

[0105]

[0106] By tracing three-dimensional polarization rays, the polarization aberration at different aperture positions of the optical system after compensation by the first plane reflector 4 and the second plane reflector 5 is calculated, as shown in FIG. Figure 6 and Figure 7As shown by the curve in the figure, a comparison of the curves in the figure shows that after the reference system is compensated using the method of the present invention, the system polarization aberration is significantly reduced, only about 1 / 6 of the reference system. This shows that the polarization aberration compensation method provided by the present invention can significantly reduce the polarization aberration of the entire optical system without changing the wavefront aberration.

[0107] Accordingly, according to an embodiment of the present invention, the present invention also provides a computer device and a storage medium.

[0108] Specifically, computer devices are represented in the form of general-purpose computing devices. Computer devices are intended to represent various forms of digital computers, such as laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. Electronic devices may also represent various forms of mobile devices, such as personal digital assistants, cellular phones, smartphones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are provided for example only and are not intended to limit the implementation of the inventions described and / or claimed herein.

[0109] Components of a computer device may include, but are not limited to, one or more processors or processing units, system memory, and buses that connect various system components.

[0110] The term "bus" refers to one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor, or a local bus using any of a variety of bus architectures. Examples of these architectures include, but are not limited to, the Industry Standard Architecture (ISA) bus, the Micro Channel Architecture (MAC) bus, the Enhanced ISA bus, the Video Electronics Standards Association (VESA) local bus, and the Peripheral Component Interconnect (PCI) bus.

[0111] Computer devices typically include a variety of computer system readable media. These media can be any available media that can be accessed by the computer device, including volatile and non-volatile media, removable and non-removable media.

[0112] The system memory may include computer system readable media in the form of volatile memory, such as random access memory (RAM) and / or cache memory. The computer device may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system may be used to read and write non-removable, non-volatile magnetic media (not shown in Figure N, commonly referred to as "hard disk drives"). In these cases, each drive may be connected to the bus via one or more data medium interfaces. The memory may include at least one program product having a set (e.g., at least one) of program modules that are configured to perform the functions of various embodiments of the present invention.

[0113] A program / utility having a set (at least one) of program modules, which may be stored, for example, in a memory, includes, but is not limited to, an operating system, one or more application programs, other program modules, and program data, each of which, or some combination thereof, may include an implementation of a network environment. The program modules generally implement the functions and / or methods of the embodiments described herein.

[0114] The computer device may also communicate with one or more external devices (e.g., a keyboard, a pointing device, a display, etc.), one or more devices that enable a user to interact with the computer device, and / or any device that enables the computer device to communicate with one or more other computing devices (e.g., a network card, a modem, etc.). Such communication may be performed via an input / output (I / O) interface. Furthermore, the computer device may communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter. The computer device may utilize other hardware and / or software modules, including but not limited to microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0115] The processing unit executes various functional applications and data processing by running the programs stored in the system memory, such as implementing the polarization aberration compensation method for the optical system provided by the embodiment of the present invention.

[0116] An embodiment of the present invention further provides a non-transitory computer-readable storage medium storing computer instructions, on which a computer program is stored. When the program is executed by a processor, the method for compensating for polarization aberration of an optical system provided by an embodiment of the present invention is implemented.

[0117] The storage medium provided in the embodiment of the present invention may adopt any combination of one or more computer-readable media. The computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. More specific examples (non-exhaustive list) of computer-readable storage media include: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, an apparatus or a device.

[0118] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0119] The program code that comprises on the computer-readable medium can be transmitted with any appropriate medium, includes but not limited to wireless, electric wire, optical cable, RF etc., or above-mentioned any suitable combination.Can write the computer program code that is used to carry out the operation of the present invention with one or more programming languages ​​or its combination, described programming language comprises object-oriented programming language such as Java, Smalltalk, C++, also comprises conventional procedural programming language--such as " C " language or similar programming language.Program code can be carried out on user's computer completely, partly on user's computer, carry out as an independent software package, partly on user's computer partly on remote computer, or carry out completely on remote computer or server.In the situation that relates to remote computer, remote computer can comprise local area network (LAN) or wide area network (WAN) to be connected to user's computer by the network of any kind, perhaps, can be connected to external computer (for example, utilize Internet service provider to come to connect by Internet).

[0120] In short, the above description is only a preferred embodiment of this specification and is not intended to limit the scope of protection of this specification. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this specification should be included in the scope of protection of this specification.

[0121] The systems, devices, modules, or units described in one or more of the above embodiments may be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0122] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0123] The various embodiments in this specification are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences between the other embodiments. In particular, the system embodiments are generally similar to the method embodiments, so the description is relatively simple. For relevant parts, refer to the description of the method embodiments.

Claims

1. A method for compensating polarization aberration of an optical system, characterized in that: include: At least one plane reflector is added to the optical path before the image plane of the optical system, and the spatial posture of each plane reflector is adjusted with the spatial posture of each plane reflector as a free variable so that the polarization aberration of the optical system meets a preset value; The spatial posture of a plane mirror is expressed by its normal vector Indicates that the normal vector The parameters are expressed as ,in, is the incident angle of the plane mirror in the spherical coordinate system, is the azimuth angle of the plane mirror in the spherical coordinate system; The method of adjusting the spatial posture of each plane reflector by taking the spatial posture of each plane reflector as a free variable includes: Based on the ray tracing data of the optical system, the central field of view main ray propagation vector and the edge ray propagation vector , and obtain the incident angle The value range of is: ； Azimuth The value range is ; At the incident angle and azimuth In the range of values, the incident angle and azimuth Assigning values, generating a plane reflector after the assignment in the optical system, calculating the polarization aberration of the optical system after the plane reflector is added, and judging whether the polarization aberration of the optical system after the plane reflector is added meets a preset value.

2. The method for compensating polarization aberration of an optical system according to claim 1, wherein: The polarization aberration of the optical system before compensation is decomposed into directional Zernike polynomials, the spatial frequency of the polarization aberration distribution is calculated, and the number of additional plane reflectors is determined in combination with a preset value that the polarization aberration of the optical system needs to meet.

3. The method for compensating polarization aberration of an optical system according to claim 1, wherein: Generating a plane reflector after assigning a value in the optical system includes: and azimuth , calculate the normal vector of the plane mirror Direction cosines in global coordinates , and the direction cosines in the global coordinate system Converted to the plane mirror coordinate system of the initial state and expressed as , the z-axis of the plane mirror coordinate system in the initial state is parallel to the z-axis of the global coordinate system; According to the direction cosines in the initial state coordinate system of the plane mirror , calculating the rotation angle of the plane reflector around the plane reflector coordinate system after the assigned value compared to the initial state, where the positive direction of the z-axis of the plane reflector coordinate system is the same as the direction of the normal vector of the plane reflector; The rotation angle of the plane reflector around the plane reflector coordinate system is input into the optical design software to generate the assigned plane reflector.

4. The method for compensating polarization aberration of an optical system according to claim 1, wherein: The polarization aberration of the optical system after adding a plane mirror is calculated by three-dimensional polarization ray tracing.

5. The method for compensating polarization aberration of an optical system according to claim 3, wherein: The rotation angle of the plane reflector around the plane reflector coordinate system includes: the rotation angle of the plane reflector around the x-axis of the plane reflector coordinate system and the rotation angle of the plane reflector around the y-axis of the plane reflector coordinate system.

6. A computer device, characterized in that: include: at least one processor; as well as a memory communicatively connected to the at least one processor; wherein, The memory stores instructions that can be executed by the at least one processor, and the instructions are executed by the at least one processor to enable the at least one processor to perform the optical system polarization aberration compensation method according to any one of claims 1 to 5.

7. A storage medium, characterized in that: Computer instructions are stored, and the computer instructions are used to enable the computer to execute the optical system polarization aberration compensation method according to any one of claims 1 to 5.

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