Method and device for simultaneously measuring pitch angle and deflection angle

Abstract

The invention discloses a method and a device for simultaneously measuring a pitch angle and a deflection angle. The method comprises the following steps: measuring phase change caused by pitching and deflection of an object plane by adopting a point shearing speckle interference method; and determining a pitch angle and a deflection angle of the object plane according to the phase change. According to the technical scheme provided by the invention, the pitch angle and deflection angle motion of the object plane can be measured, and the measurement speed of the pitch angle and the deflection angle is effectively improved, so that the method can meet the requirement of timely feedback of the pitch angle and deflection angle motion in an industrial field.

Description

Technical Field

[0001] The present application relates to the field of optical measurement technology, and in particular to a method and device for simultaneously measuring pitch angle and yaw angle. Background Art

[0002] As core equipment in modern manufacturing, the machining accuracy of precision CNC machine tools directly determines the quality of high-end manufactured products. With the rapid development of the manufacturing industry toward ultra-precision, the requirements for the motion accuracy of CNC machine tools are becoming increasingly stringent. The geometric errors generated by machine tools during high-speed movement, especially multi-degree-of-freedom coupling errors, have become a key factor restricting the improvement of machining accuracy. Taking linear guides as an example, the six-degree-of-freedom errors generated during their movement will directly affect the form and position tolerances of the workpiece. Among them, errors in the pitch and yaw angles will cause relative posture deviations between the tool and the workpiece, resulting in defects such as ripples and tilt on the machined surface. Therefore, achieving high-precision real-time measurement of the pitch and yaw angles is of great engineering significance for error compensation and process optimization.

[0003] However, the simultaneous measurement of pitch and yaw angles faces significant technical challenges. Traditional contact measurement methods require the installation of displacement sensors or co-targets on the machine tool's moving parts, which not only introduces additional mass interference but can also lead to measurement inaccuracies due to mechanical vibration. Non-contact optical measurement technology, while able to avoid the limitations of contact measurement, currently available methods are often designed for a single degree of freedom, making it difficult to achieve simultaneous resolution of pitch and yaw angles. Furthermore, image processing-based visual measurement solutions rely on complex feature extraction and matching algorithms, resulting in insufficient real-time performance and unable to meet the dynamic measurement requirements of high-speed machining scenarios.

[0004] Therefore, there is an urgent need for a non-contact, high-precision, and real-time method for synchronous measurement of pitch and yaw angles to break through the limitations of existing technologies and provide reliable data support for multi-degree-of-freedom error compensation of CNC machine tools. Summary of the Invention

[0005] A brief overview of the present application is provided below to provide a basic understanding of certain aspects of the present application. It should be understood that this overview is not an exhaustive overview of the present application. It is not intended to identify key or important portions of the present application, nor is it intended to limit the scope of the present application. Its purpose is simply to present certain concepts in a simplified form as a prelude to the more detailed description that will be discussed later.

[0006] The embodiments of the present application provide a method and apparatus for simultaneously measuring pitch angle and yaw angle.

[0007] In a first aspect, an embodiment of the present application provides a method for simultaneously measuring pitch angle and yaw angle, comprising:

[0008] Point shear speckle interferometry is used to measure the phase change caused by the pitch and yaw of the object surface;

[0009] The pitch angle and yaw angle of the object plane are determined according to the phase change.

[0010] Optionally, point shearing speckle interferometry is used to measure the phase, including:

[0011] Use expanded beam laser to illuminate the object surface to generate diffuse reflected light;

[0012] The diffusely reflected light enters a shearing module to generate a pair of mutually offset but partially overlapping light beams;

[0013] The pair of mutually offset but partially overlapping light beams interfere with each other on one or more photodetector surfaces after passing through a phase modulation module, forming point shear speckle interferometry;

[0014] The signal of the point shearing speckle interferometry is received by the photoelectric detector, then processed by a signal acquisition and processing module, and finally the phase is extracted by a phase determination module.

[0015] Optionally, the point shearing module includes an x-direction shearing unit and a y-direction shearing unit that are orthogonally arranged.

[0016] Optionally, the measuring of phase changes caused by pitch and yaw of an object plane by using point shearing speckle interferometry includes:

[0017] Measuring first phase information of the object plane at time i by using the point shearing speckle interferometry method;

[0018] Measuring the second phase information of the object plane at time j by using the point shearing speckle interferometry method, wherein j>i;

[0019] The phase change caused by the yaw or pitch of the object plane within a time period ji is determined according to the difference between the first phase information and the second phase information.

[0020] Optionally, the phase change caused by the pitch or yaw of the object plane within a time period of ji is in the range of (-π, π).

[0021] Optionally, the method further includes:

[0022] When the phase change caused by the pitch or yaw exceeds 2π, the ji period is divided into multiple sub-periods, and the phase change caused by the pitch or yaw of the object plane in each sub-period is within the range of (-π, π);

[0023] The phase changes caused by the pitch or yaw in each sub-period are accumulated to obtain a total phase change.

[0024] Optionally, determining the pitch angle of the object plane according to the phase information includes:

[0025] According to the total phase change, the pitch angle of the object plane is determined using the following formula;

[0026]

[0027] The pitch axis of the object plane is the X axis, Rx is the pitch angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δy is the shearing amount of the shearing module.

[0028] Optionally, determining the yaw angle of the object plane according to the phase information includes:

[0029] According to the total phase change, the yaw angle of the object plane is determined using the following formula:

[0030]

[0031] The deflection axis of the object plane is the Y axis, Ry is the deflection angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δx is the shearing amount of the shearing module.

[0032] In a second aspect, an embodiment of the present application further provides a device for simultaneously measuring pitch angle and yaw angle, comprising:

[0033] Point shearing speckle interferometry measurement module, used to measure the total phase change corresponding to the beam expansion laser caused by the pitch and yaw of the object plane using point shearing speckle interferometry;

[0034] The pitch angle and yaw angle determination module is used to determine the pitch angle and yaw angle of the object plane according to the total phase change.

[0035] Optionally, the point shearing speckle interferometry measurement module includes:

[0036] A laser source, a beam expander for expanding the laser beam and irradiating the laser beam onto an object plane, a shearing element for shearing scattered light from the object plane, and a detector for recording the intensity of interference light;

[0037] The pitch angle and yaw angle determination module is specifically used for:

[0038] Acquiring first interference light intensity information before pitching and yaw of the object plane and second interference light intensity information after pitching and yaw of the object plane, recorded by the point shearing speckle interferometry measurement module;

[0039] determining first phase distribution information of the object plane based on the first interference light intensity information;

[0040] determining second phase distribution information of the object plane based on the second interference light intensity information;

[0041] determining a total phase change caused by the pitch and yaw of the object plane based on the first phase distribution information and the second phase distribution information;

[0042] The following formula is used to determine the pitch angle of any point on the object surface:

[0043]

[0044] Wherein, the pitch axis of the object plane is the X axis, Rx is the pitch angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δy is the shearing amount of the shearing module in the y direction;

[0045] The following formula is used to determine the yaw angle of any point on the object surface:

[0046]

[0047] The deflection axis of the object plane is the Y axis, Ry is the deflection angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δx is the shearing amount of the shearing module in the x direction.

[0048] The point shearing speckle interferometry method is used to measure the phase change caused by the pitch and yaw of the object surface, and then the pitch angle and yaw angle of the object surface are determined according to the phase change, thereby realizing non-contact real-time simultaneous measurement of the pitch angle and yaw angle of the object surface.

[0049] These and other advantages of the present application will become more apparent through the following detailed description of the optional embodiments of the present application in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The present application may be better understood by referring to the following description in conjunction with the accompanying drawings, wherein the same or similar reference numerals are used throughout the drawings to represent the same or similar components. The accompanying drawings, together with the following detailed description, are incorporated into and form a part of this specification and are used to further illustrate the optional embodiments of the present application and to explain the principles and advantages of the present application. In the drawings:

[0051] Figure 1 A flow chart of a pitch angle and yaw angle measurement method provided in an embodiment of the present application;

[0052] Figure 2 This is an optional example of a shearing implementation device provided in an embodiment of the present application;

[0053] Figure 3 An optional example of measuring pitch angle and yaw angle based on point shearing speckle interferometry provided in an embodiment of the present application;

[0054] Figure 4 An optional example of measuring pitch angle and yaw angle based on point shearing speckle interferometry provided in an embodiment of the present application;

[0055] Figure 5 A block diagram of a pitch angle and yaw angle measurement device provided in an embodiment of the present application;

[0056] Figure 6 This is a logic block diagram of a measurement system provided in an embodiment of the present application.

[0057] Those skilled in the art will appreciate that the elements in the drawings are shown for simplicity and clarity only and are not necessarily drawn to scale. For example, the dimensions of certain elements in the drawings may be exaggerated relative to other elements to facilitate a better understanding of the embodiments of the present application. DETAILED DESCRIPTION

[0058] Exemplary embodiments of the present application will be described in detail below with reference to the accompanying drawings. For the sake of clarity and conciseness, not all features of actual implementations are described in the specification. However, it should be understood that many implementation-specific decisions must be made in the process of developing any such actual implementation in order to achieve the developer's specific goals, such as meeting those constraints related to the system and business, and these constraints may vary from implementation to implementation. In addition, it should be understood that although the development work may be very complex and time-consuming, it is a routine task for those skilled in the art who benefit from the content of this disclosure.

[0059] It is also necessary to explain here that, in order to avoid obscuring the present application due to unnecessary details, only the device structure and / or processing steps closely related to the scheme according to the present application are described in the drawings and descriptions, while the representation and description of components and processes that are not closely related to the present application and are known to ordinary technicians in this field are omitted.

[0060] It should be noted that the shearing device structures described in all embodiments of this patent are optional examples for explaining the working principle, and the scope of protection of the claims is not limited to the specific structures shown in the illustrations. Any device that can produce a controllable amount of shear between coherent light beams through optical means falls within the technical solution of this patent.

[0061] The following is a further detailed description of the specific implementation methods of the present application in conjunction with the accompanying drawings (same reference numerals in several drawings represent same elements) and examples. The following examples are used to illustrate the present application but are not intended to limit the scope of the present application.

[0062] Point shear speckle interferometry is a non-contact optical measurement technology capable of measuring deformation and strain in engineering materials. It boasts short measurement times, high accuracy, high stability, and non-contact measurement. Because point shear speckle interferometry is deformation-sensitive, it establishes a relationship between phase and deformation. Compared to other non-contact pitch and yaw angle measurement methods, such as digital shear speckle interferometry, which requires processing the full-field phase distribution information on the object surface, point shear speckle interferometry only processes the phase value at a single point on the object surface, significantly improving the pitch and yaw angle measurement speed and meeting the needs of rapid measurement in industry.

[0063] Based on extensive research and experimental demonstration, the applicant has proposed point shearing speckle interferometry (SSI) technology and applied it to the real-time, simultaneous, and rapid measurement of pitch and yaw angles. Based on this discovery, the present application introduces SSI for the first time into the simultaneous measurement of pitch and yaw angles, providing a novel solution for measuring pitch and yaw angles. The following describes in detail the technical solutions of exemplary embodiments of the present application, with reference to the accompanying drawings.

[0064] Figure 1 This is a flow chart of a pitch angle and yaw measurement method provided in an embodiment of the present application. Figure 1 As shown, the pitch angle and yaw angle measurement method provided in the embodiment of the present application includes:

[0065] S101: Use point shear speckle interferometry to measure the phase changes caused by the pitch and yaw of the object surface.

[0066] S102: Determine the pitch angle and yaw angle of the object plane according to the phase change.

[0067] Unlike traditional pitch and yaw angle measurement methods, the present embodiment determines the pitch and yaw angles of an object using point shearing speckle interferometry. Using a photodetector to collect the shearing speckle interferometry signal at a single point on the object surface, this method effectively avoids full-field signal processing and enables non-contact measurement of the pitch and yaw angles, reducing measurement errors. Furthermore, the pitch and yaw angle measurement method based on point shearing speckle interferometry in the present embodiment utilizes fewer components, a simple structure, and intuitive, real-time measurement results.

[0068] Optionally, using point shear speckle interferometry to measure phase changes caused by pitch and yaw of the object plane includes: using the point shear speckle interferometry to measure a total phase change of the object plane corresponding to the beam expansion laser.

[0069] Optionally, determining the pitch angle and yaw angle of the object plane according to the phase change includes: utilizing a geometric relationship between the pitch angle, yaw angle and phase change, substituting the total phase change, and then solving the pitch angle and yaw angle.

[0070] The following further describes the theoretical basis and specific exemplary methods of the pitch angle and yaw angle measurement solution based on point shearing speckle interferometry technology of the present application.

[0071] Figure 2 This is an optional example of a shearing implementation device provided in an embodiment of the present application. Laser light emitted by laser 1 is incident on beam splitter prism 2 and split into a first beam and a second beam. The first beam is reflected by fixed reflector 4 and returns to beam splitter prism 2, while the second beam is reflected by adjustable reflector 3 and returns to beam splitter prism 2. The two beams are combined and incident on detector 5. By adjusting the inclination angle of adjustable reflector 3 around the X-axis or Y-axis, a controllable amount of shear is introduced into the combined beam wavefront, allowing detector 5 to record interference light intensity information.

[0072] Figure 2 The shearing device shown is only an exemplary structure for achieving shearing. Those skilled in the art should understand that any optical device that can introduce a controllable amount of shear is suitable for the present invention, including but not limited to Michelson interference structure, Wollaston prism, Rochon prism, tilted parallel plate, diffraction grating pair and programmable spatial light modulator, etc.

[0073] Figure 3 An optional example of measuring pitch angle and yaw angle based on point shearing speckle interferometry is provided in an embodiment of the present application. Figure 3 The optical path of the point shear interferometry shown is the optical path for off-plane deformation measurement. Figure 3 In the point shearing speckle interferometry measurement optical path shown, the light emitted by the laser 1 passes through the reflector 2 and the beam expander 3 and is incident on the object plane 4. The reflected light reflected by the object plane enters the shearing system. The reflected light is divided into object light and reference light after passing through the beam splitter 5. The object light passes through the reflector 8 and enters the photodetector 6. The reference light passes through the reflector 7 and is irradiated onto the sensor surface of the photodetector 8 to form interference, namely point shearing speckle interference. A piezoelectric ceramic tube 9 is provided on the back of the reflector 7. By controlling the elongation of the piezoelectric ceramic tube, multiple additional optical paths are introduced into the optical path where the reference light is located (the specific value of each additional optical path depends on the time phase shift algorithm adopted, which can be a quarter of the wavelength of light or other values). The X-axis is the pitch axis of the object plane, the Y-axis is the yaw axis of the object plane, and the measurement system is set on the XOZ plane;

[0074] Figure 4 Another optional example of measuring pitch angle and yaw angle based on point shearing speckle interferometry provided in an embodiment of the present application. Figure 4 The optical path for point shear interferometry is also the optical path for out-of-plane deformation measurement. Figure 4In the point shearing speckle interferometry optical path shown, light emitted by laser 1 passes through reflector 2 and beam expander 3 and is incident on object plane 4. The reflected light from the object plane enters the shearing system. The reflected light passes through beam splitter prism 5 and is split into object light and reference light. The object light passes through reflector 8 and enters microlens array 9, then passes through polarizer array 10 and enters photodetector array 6. The reference light passes through reflector 7 and illuminates microlens array 9, then passes through polarizer array 10 and enters the sensor surface of photodetector array 6, forming interference, namely point shearing speckle interferometry. The microlens array 9 splits the light beam, and the polarization angle of the polarizer array 10 depends on the spatial phase shift algorithm used and can be 0°, 90°, 45°, 135°, or other values. The X-axis is the pitch axis of the object plane, and the Y-axis is the yaw axis of the object plane. The measurement system is set in the XOZ plane.

[0075] It should be noted that the point shearing speckle interferometry measurement optical path can adopt the above Figure 3 、 Figure 4 In addition to the optical path form, other optical path deformations and component replacements that can perform point shearing speckle interferometry also fall within the scope of protection of this application. Detailed descriptions are given below.

[0076] In one possible implementation, an expanded beam laser is used to illuminate the object surface to generate diffusely reflected light;

[0077] like Figure 3 or Figure 4 As shown, the light emitted by the laser 1 passes through the reflector 2 and the beam expander 3 and is incident on the object surface to generate diffusely reflected light.

[0078] In a possible implementation, the diffusely reflected light enters a shearing module to generate a pair of mutually offset but partially overlapping light beams;

[0079] like Figure 3 or Figure 4 As shown, the diffusely reflected light enters a shearing module, generating a pair of mutually offset but partially overlapping light beams.

[0080] In a possible implementation, the pair of mutually offset but partially overlapping light beams pass through a phase modulation module and interfere on one or more photodetector surfaces to form point shear speckle interferometry;

[0081] like Figure 3 As shown, the phase shift is introduced by changing the interference phase difference by the deformation of the piezoelectric ceramic 9. After the pair of mutually offset but partially overlapping light beams pass through a phase modulation module based on time phase shift, they interfere on the surface of a photodetector 6, forming point shear speckle interferometry.

[0082] like Figure 4As shown, a spatial phase shift is introduced by using a microlens array 9 and a polarizer array 10. After the pair of mutually offset but partially overlapping light beams pass through a phase modulation module based on spatial phase shift, they interfere on the surface of a photodetector array 6, forming point shear speckle interference.

[0083] In a possible implementation, the point shearing speckle interferometry signal is received by the photodetector, then processed by a signal acquisition and processing module, and finally a phase determination module is used to extract the phase;

[0084] like Figure 3 As shown, the signal of the point shearing speckle interferometry is received by the photodetector 6, then processed by a signal acquisition and processing module, and finally the phase is extracted by a phase determination module based on time phase shift. The following formula is used to determine the wrapping phase:

[0085]

[0086] Wherein, I1, I2, I3, and I4 represent the point shear speckle interference light intensity corresponding to different telescopic steps of the piezoelectric ceramic 9;

[0087] like Figure 4 As shown, the signal from the point shearing speckle interferometry is received by the photodetector array 6, then processed by a signal acquisition and processing module, and finally the phase is extracted by a phase determination module based on spatial phase shift. The spatial phase shift is introduced using a microlens array 9 and a polarizer array 10, and the wrapping phase is determined using the following formula:

[0088]

[0089] Among them, I1, I2, I3, and I4 represent the point shear speckle interference intensity corresponding to the polarization directions of 0°, 45°, 90°, and 135°, respectively.

[0090] In a possible implementation, the shearing module includes an x-direction shearing unit and a y-direction shearing unit that are orthogonally arranged;

[0091] like Figure 3 or Figure 4 As shown, the shearing module includes an x-direction shearing unit and a y-direction shearing unit arranged orthogonally.

[0092] In one possible implementation, measuring the phase change caused by the pitch and yaw of the object plane using the point shearing speckle interferometry method includes: measuring first phase information of the object plane at time i using the point shearing speckle interferometry method; measuring second phase information of the object plane at time j using the point shearing speckle interferometry method, where j is greater than i; and determining, based on the first phase information and the second phase information, the phase change corresponding to the beam expansion laser caused by the pitch and yaw of the object plane in a time period ji;

[0093] like Figure 3 or Figure 4 As shown in the figure, at time i, after the laser is incident and expanded onto the object surface, the first phase information is measured using point shearing speckle interferometry. At time j, after the laser is incident and expanded onto the object surface, the second phase information is measured using point shearing speckle interferometry. Based on the phase information of the expanded laser at times i and j, the phase change of the expanded laser caused by the pitch and yaw of the object surface during time period ji is determined.

[0094] In a possible implementation, the phase change caused by the pitch and yaw of the object plane within a time period ji is within a range of (-π, π);

[0095] like Figure 3 or Figure 4 As shown, the phase change caused by the pitch and yaw of the object plane in the ji period is in the range of (-π, π).

[0096] In one possible implementation, when the phase change caused by the pitch and yaw exceeds 2π, the ji period is divided into multiple sub-periods, and the phase change caused by the pitch and yaw of the object plane in each sub-period is within the range of (-π, π); the phase change caused by the pitch and yaw in each sub-period is accumulated to obtain a total phase change;

[0097] like Figure 3 or Figure 4 As shown, when the phase change caused by the pitch and yaw exceeds 2π, the ji period is divided into multiple sub-periods, and the phase change caused by the pitch and yaw of the object plane in each sub-period is within the range of (-π, π); the phase change caused by the pitch and yaw in each sub-period is accumulated to obtain the total phase change.

[0098] In a possible implementation, the pitch angle of the object plane is determined according to the total phase change using the following formula:

[0099]

[0100] Wherein, the pitch axis of the object plane is the X axis, Rx is the pitch angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δy is the shearing amount of the shearing module;

[0101] like Figure 3 or Figure 4 As shown, according to the total phase change, the pitch angle of the object plane is determined using the following formula:

[0102]

[0103] The pitch axis of the object plane is the X axis, Rx is the pitch angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δy is the shearing amount of the shearing module.

[0104] In a possible implementation, the yaw angle of the object plane is determined according to the total phase change using the following formula:

[0105]

[0106] Wherein, the deflection axis of the object plane is the Y axis, Ry is the deflection angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δx is the shearing amount of the shearing module;

[0107] like Figure 3 or Figure 4 As shown, according to the total phase change, the deflection angle of the object plane is determined using the following formula:

[0108]

[0109] The deflection axis of the object plane is the Y axis, Ry is the deflection angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δx is the shearing amount of the shearing module.

[0110] Those skilled in the art will understand that in any of the above methods of the specific implementation methods of the present application, the serial number of each step does not mean the order of execution. The execution order of each step should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the specific implementation methods of the present application.

[0111] Figure 5 This is a block diagram of a pitch angle and yaw angle measurement device provided in an embodiment of the present application. Figure 5 As shown, an embodiment of the present application provides a pitch angle and yaw angle measurement device including: a point shearing speckle interferometry measurement module 51 and a pitch angle and yaw angle determination module 52 .

[0112] Point shearing speckle interferometry measurement module, used to measure the total phase change corresponding to the beam expansion laser caused by the pitch and yaw of the object plane using point shearing speckle interferometry;

[0113] The pitch angle and yaw angle determination module is used to determine the pitch angle and yaw angle of the object plane according to the total phase change.

[0114] Optionally, the point shearing speckle interferometry measurement module 51 includes:

[0115] A laser source, a beam expander for expanding the laser beam and irradiating the laser beam onto an object plane, a shearing element for shearing scattered light from the object plane, and a detector for recording the intensity of interference light;

[0116] Optionally, the pitch angle and yaw angle determination module 52 is specifically configured to:

[0117] Acquiring first interference light intensity information before pitching and yaw of the object plane and second interference light intensity information after pitching and yaw of the object plane, recorded by the point shearing speckle interferometry measurement module;

[0118] determining first phase distribution information of the object plane based on the first interference light intensity information;

[0119] determining second phase distribution information of the object plane based on the second interference light intensity information;

[0120] A total phase change caused by the pitch and yaw of the object plane is determined according to the first phase distribution information and the second phase distribution information.

[0121] The pitch angle and yaw angle measuring device provided in the embodiment of the present application can be used to implement the above Figure 1 The various steps of the method embodiment of the pitch angle and yaw angle measurement method shown in the figure (for various further preferred embodiments, they are not described in detail in the embodiment of the pitch angle and yaw angle measurement device, and can be found in detail in Figure 1 The pitch angle and yaw angle measurement method shown in the embodiment is used to determine the pitch angle and yaw angle of the object surface, which has a wide range of applications, a simple structure, a fast measurement speed and intuitive measurement results.

[0122] Figure 6 This is a logic block diagram of a measurement system provided in an embodiment of the present application. Figure 6 As shown, the measurement system provided by the embodiment of the present application includes: a pitch angle and yaw angle measuring device 601, a processor 602 and a memory 603; the processor 602 is connected to the pitch angle and yaw angle measuring device 601 and the memory 603 respectively, optionally, the processor 602 can be communicatively connected to the pitch angle and yaw angle measuring device 601 via a bus and a communication interface, and the processor 602 and the memory 603 can be communicatively connected via a bus.

[0123] The processor 602 is configured to execute a program, specifically, to execute the relevant steps in the above-described embodiment of the pitch and yaw angle measurement method. For example, the program may include program code, which includes computer operating instructions. The memory 603 is configured to store at least one instruction, which causes the processor 602 to perform the following operations: control the pitch and yaw angle measurement device 601 to measure phase information caused by the pitch and yaw of the object plane, and determine the pitch and yaw angle of the object plane based on the phase information; or control the pitch and yaw angle measurement device 601 to measure phase information caused by the pitch and yaw of the object plane, and determine the pitch and yaw angle of the object plane based on the phase information.

[0124] The processor 602 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0125] The memory 603 may include a random access memory (RAM), and may also include a non-volatile memory (Non-volatile memory), such as at least one disk memory.

[0126] The specific implementation of each step in the program executed by the processor can be found in the corresponding descriptions of the corresponding steps, modules, submodules, and units in the above embodiments, and will not be repeated here. Those skilled in the art will clearly understand that for the convenience and brevity of description, the specific working processes of the above-described devices and modules can refer to the corresponding process descriptions in the above-mentioned method embodiments, and will not be repeated here.

[0127] In the above-mentioned embodiments of the present application, the serial numbers and / or the order of the embodiments are only for the convenience of description and do not represent the advantages or disadvantages of the embodiments. The description of each embodiment has its own focus. For parts not described in detail in a certain embodiment, please refer to the relevant description of other embodiments. For the relevant description of the implementation principles or processes of the relevant device, equipment or system embodiments, please refer to the description of the corresponding method embodiments, which will not be repeated here.

[0128] Those skilled in the art will appreciate that the units and method steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0129] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes a number of instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0130] In the embodiments of the device, method, system, etc. of the present application, it is obvious that each component (system, subsystem, module, submodule, unit, subunit, etc.) or each step can be decomposed, combined and / or recombined after decomposition. These decompositions and / or recombinations should be regarded as equivalent schemes of the present application. At the same time, in the above description of the specific embodiments of the present application, the features described and / or shown for one embodiment can be used in one or more other embodiments in the same or similar manner, combined with the features in other embodiments, or replace the features in other embodiments.

[0131] It should be emphasized that the term "include / comprises" when used herein refers to the existence of features, elements, steps or components, but does not exclude the existence or addition of one or more other features, elements, steps or components.

[0132] Finally, it should be noted that the above implementation methods are only used to illustrate the present application and are not intended to limit the present application. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present application. Therefore, all equivalent technical solutions also fall within the scope of the present application, and the scope of patent protection of the present application should be defined by the claims.

Claims

1. A method for simultaneously measuring pitch angle and yaw angle, characterized in that: include: Point shear speckle interferometry is used to measure the phase change caused by the pitch and yaw of the object surface; The pitch angle and yaw angle of the object plane are determined according to the phase change.

2. The method according to claim 1, characterized in that Point shearing speckle interferometry measures phase, including: Use expanded beam laser to illuminate the object surface to generate diffuse reflected light; The diffusely reflected light directly enters a shearing module to generate a pair of mutually offset but partially overlapping light beams; The pair of mutually offset but partially overlapping light beams interfere with each other on one or more photodetector surfaces after passing through a phase modulation module, forming point shear speckle interferometry; The signal of the point shearing speckle interferometry is received by the photoelectric detector, then processed by a signal acquisition and processing module, and finally the phase is extracted by a phase determination module.

3. The method according to claim 2, characterized in that The shearing module includes an x-direction shearing unit and a y-direction shearing unit that are orthogonally arranged.

4. The method according to claim 1, wherein The method of measuring the phase change caused by the pitch and yaw of the object plane by using the point shearing speckle interferometry method includes: Measuring first phase information of the object plane at time i by using the point shearing speckle interferometry method; The point shearing speckle interferometry method is used to measure the second phase information of the object plane at time j, wherein j>i; The phase change caused by the yaw and pitch of the object plane within the ji period is determined according to the difference between the first phase information and the second phase information.

5. The method according to claim 4, characterized in that The phase change caused by the pitch and yaw of the object plane within the ji time period is within the range of (-π, π).

6. The method according to claim 4, characterized in that The method also includes: when the phase change caused by the pitch and yaw exceeds 2π, dividing the ji period into multiple sub-periods, and the phase change caused by the pitch and yaw of the object plane in each sub-period is within the range of (-π, π); accumulating the phase change caused by the pitch and yaw in each sub-period to obtain a total phase change.

7. The method according to claim 4, characterized in that Determining the pitch angle and yaw angle of the object plane according to the phase change includes determining the pitch angle of the object plane according to the total phase change using the following formula; The pitch axis of the object plane is the X axis, α is the pitch angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δy is the shearing amount of the shearing module in the y direction.

8. The method according to claim 4, characterized in that Determining the pitch angle and yaw angle of the object plane according to the phase change includes determining the yaw angle of the object plane according to the total phase change using the following formula; The yaw axis of the object plane is the Y axis, R y is the deflection angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δx is the shearing amount of the shearing module in the x direction.

9. A device for simultaneously measuring pitch angle and yaw angle, characterized in that: include: Point shearing speckle interferometry measurement module, used to measure the total phase change corresponding to the beam expansion laser caused by the pitch and yaw of the object plane using point shearing speckle interferometry; The pitch angle and yaw angle determination module is used to determine the pitch angle and yaw angle of the object plane according to the total phase change.

10. The device according to claim 9, characterized in that The point shearing speckle interferometry measurement module includes: A laser source, a beam expander for expanding the laser beam and irradiating the laser beam onto an object plane, a shearing element for shearing scattered light from the object plane, and a detector for recording the intensity of interference light; The pitch angle and yaw angle determination module is specifically used for: Acquiring first interference light intensity information before pitching and yaw of the object plane and second interference light intensity information after pitching and yaw of the object plane, recorded by the point shearing speckle interferometry measurement module; determining first phase distribution information of the object plane based on the first interference light intensity information; determining second phase distribution information of the object plane based on the second interference light intensity information; determining a total phase change caused by the pitch and yaw of the object plane based on the first phase distribution information and the second phase distribution information; The following formula is used to determine the pitch angle of any point on the object surface: The pitch axis of the object plane is the X axis, R x is the pitch angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δy is the shearing amount of the shearing module in the y direction; The following formula is used to determine the yaw angle of any point on the object surface: The yaw axis of the object plane is the Y axis, R y is the deflection angle of the object plane, Δ is the total phase change, λ is the wavelength of the beam expansion laser, and δx is the shearing amount of the shearing module in the x direction.

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