Method and device for determining measurement accuracy of digital speckle interferometry system

Abstract

The present disclosure relates to a method and device for determining the measurement accuracy of a digital speckle interferometry system. The method comprises: using a laser dual-frequency interferometer to monitor an object plane to perform multiple deflections around a deflection axis, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle; using a digital speckle interferometry system to measure a first surface deformation corresponding to each deflection of a target observation point in the object plane; and determining the surface deformation measurement accuracy of the digital speckle interferometry system based on the first preset angle and the first surface deformation corresponding to each deflection of the target observation point. The present disclosure can realize the accuracy evaluation of the surface deformation measurement of the digital speckle interferometry system, and further can effectively realize the calibration and correction of the digital speckle interferometry system when measuring the surface deformation.

Description

Technical Field

[0001] The present disclosure relates to the technical field of full-field light measurement, and in particular to a method and device for determining the measurement accuracy of a digital speckle interferometry system. Background Art

[0002] Digital speckle pattern interferometry is a full-field optical testing technology that can measure tiny deformations and strains. It is widely used in aerospace, precision instrument testing and other fields, but its measurement accuracy cannot be calibrated and evaluated at present. Calibrating and calibrating the digital speckle pattern interferometry system will be more conducive to the application of digital speckle pattern interferometry technology. Therefore, a method for calibrating and determining the measurement accuracy of the digital speckle pattern interferometry system is urgently needed. Summary of the invention

[0003] In view of this, the present disclosure proposes a method and device for calibrating and evaluating the measurement accuracy of a digital speckle interferometry system.

[0004] According to one aspect of the present disclosure, a method for determining measurement accuracy of a digital speckle interferometry system is provided, comprising:

[0005] A laser dual-frequency interferometer is used to monitor the object plane to perform multiple deflections around the deflection axis, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle;

[0006] A digital speckle interferometry system is used to measure the first surface shape deformation corresponding to each deflection of a target observation point in the object plane;

[0007] The surface deformation measurement accuracy of the digital speckle interferometry system is determined according to the first preset angle and the first surface deformation corresponding to each deflection of the target observation point.

[0008] In a possible implementation manner, determining the surface deformation measurement accuracy of the digital speckle interferometry system according to the first preset angle and the first surface deformation corresponding to each deflection of the target observation point includes:

[0009] Determining a second surface deformation corresponding to the target observation point according to the first preset angle;

[0010] The surface deformation measurement accuracy of the digital speckle interferometry system is determined according to the difference between the second surface deformation and the first surface deformation corresponding to each deflection of the target observation point.

[0011] In a possible implementation manner, determining the second surface deformation corresponding to the target observation point according to the first preset angle includes:

[0012] The second surface deformation is determined by the following formula:

[0013] Δω=Δθ·Δx;

[0014] Among them, Δω is the second surface deformation, Δθ is the first preset angle, and Δx is the distance from the target observation point to the yaw axis.

[0015] In a possible implementation, the measuring the first surface shape deformation corresponding to each deflection of the target observation point in the object plane by using a digital speckle interferometry system includes:

[0016] For any deflection, the digital speckle interferometry system is used to determine the object plane phase change caused by the deflection;

[0017] According to the object plane phase change, the first surface shape deformation corresponding to the current deflection of the target observation point is determined.

[0018] According to another aspect of the present disclosure, a method for determining measurement accuracy of a digital speckle interferometry system is provided, comprising:

[0019] A laser dual-frequency interferometer is used to monitor the object plane to perform multiple rolls around the roll axis, wherein the angle of each roll of the object plane around the roll axis is a second preset angle;

[0020] Using a digital speckle interferometry system to measure the first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object plane;

[0021] The in-plane deformation measurement accuracy of the digital speckle interferometry system is determined according to the second preset angle and the first in-plane deformation difference corresponding to each rolling of the first target observation point and the second target observation point.

[0022] In a possible implementation manner, determining the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second preset angle and the first in-plane deformation difference corresponding to each rolling of the first target observation point and the second observation point includes:

[0023] Determine, according to the second preset angle, a second in-plane deformation difference corresponding to the first target observation point and the second target observation point;

[0024] The in-plane deformation measurement accuracy of the digital speckle interferometry system is determined according to the second in-plane deformation difference and the difference between the first in-plane deformation differences corresponding to each rolling of the first target observation point and the second target observation point.

[0025] In a possible implementation manner, determining, according to the second preset angle, the second in-plane deformation difference corresponding to the first target observation point and the second target observation point includes:

[0026] Determining a horizontal distance between the first target observation point and the second target observation point;

[0027] The second in-plane deformation difference is determined according to the product of the second preset angle and the horizontal distance.

[0028] In a possible implementation manner, the using a digital speckle interferometry system to measure the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point in the object plane includes:

[0029] For any roll, the digital speckle interferometry system is used to determine the object plane phase change caused by the roll;

[0030] According to the object plane phase change, a first in-plane deformation difference corresponding to the current roll of the first target observation point and the second target observation point is determined.

[0031] According to another aspect of the present disclosure, there is provided a device for determining measurement accuracy of a digital speckle interferometry system, comprising:

[0032] A deflection module, used for monitoring the object plane to perform multiple deflections around a deflection axis using a laser dual-frequency interferometer, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle;

[0033] A surface deformation measurement module, used for measuring a first surface deformation corresponding to each deflection of a target observation point in the object plane by using a digital speckle interferometry system;

[0034] The first determination module is used to determine the surface deformation measurement accuracy of the digital speckle interferometry system according to the first preset angle and the first surface deformation corresponding to each deflection of the target observation point.

[0035] According to another aspect of the present disclosure, there is provided a device for determining measurement accuracy of a digital speckle interferometry system, comprising:

[0036] A rolling module, used for monitoring the object plane to perform multiple rollings around the rolling axis by using a laser dual-frequency interferometer, wherein the angle of each rolling of the object plane around the rolling axis is a second preset angle;

[0037] An in-plane deformation measurement module, used for measuring a first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object plane by using a digital speckle interferometry system;

[0038] The second determination module is used to determine the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second preset angle and the first in-plane deformation difference corresponding to each rolling of the first target observation point and the second target observation point.

[0039] A laser dual-frequency interferometer is used to monitor the object surface to perform multiple deflections around a deflection axis, wherein the angle of each deflection of the object surface around the deflection axis is a first preset angle; a digital speckle pattern interferometry system is used to measure a first surface shape deformation corresponding to each deflection of a target observation point in the object surface; and the surface shape deformation measurement accuracy of the digital speckle pattern interferometry system is determined according to the first preset angle and the first surface shape deformation corresponding to each deflection of the target observation point, thereby realizing the accuracy evaluation of the surface shape deformation measurement of the digital speckle pattern interferometry system, and further realizing the calibration and correction of the digital speckle pattern interferometry system effectively when measuring the surface shape deformation.

[0040] A laser dual-frequency interferometer is used to monitor the object surface to perform multiple rolls around the roll axis, wherein the angle of each roll of the object surface around the roll axis is a second preset angle; a digital speckle pattern interferometry system is used to measure the first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object surface; and the in-plane deformation measurement accuracy of the digital speckle pattern interferometry system is determined according to the second preset angle and the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point, so that the accuracy evaluation of the in-plane deformation measurement of the digital speckle pattern interferometry system can be achieved, and further, the digital speckle pattern interferometry system can be effectively calibrated and calibrated during the in-plane deformation measurement.

[0041] Further features and aspects of the present disclosure will become apparent from the following detailed description of exemplary embodiments with reference to the attached drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate exemplary embodiments, features, and aspects of the disclosure and, together with the description, serve to explain the principles of the disclosure.

[0043] Figure 1 A flow chart showing a method for determining measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure;

[0044] Figure 2 A schematic diagram of an optical path for determining the measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown;

[0045] Figure 3 A flow chart showing a method for determining measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure;

[0046] Figure 4 A schematic diagram of an optical path for determining the measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown;

[0047] Figure 5 A block diagram showing a device for determining measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure;

[0048] Figure 6A block diagram of a device for determining measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown. DETAILED DESCRIPTION

[0049] Various exemplary embodiments, features and aspects of the present disclosure will be described in detail below with reference to the accompanying drawings. The same reference numerals in the accompanying drawings represent elements with the same or similar functions. Although various aspects of the embodiments are shown in the accompanying drawings, the drawings are not necessarily drawn to scale unless otherwise specified.

[0050] The word “exemplary” is used exclusively herein to mean “serving as an example, example, or illustration.” Any embodiment described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments.

[0051] In addition, in order to better illustrate the present disclosure, numerous specific details are given in the following specific embodiments. It should be understood by those skilled in the art that the present disclosure can also be implemented without certain specific details. In some examples, methods, means, components and circuits well known to those skilled in the art are not described in detail in order to highlight the subject matter of the present disclosure.

[0052] Figure 1 A flow chart showing a method for determining the measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown. Figure 1 As shown, the method may include:

[0053] Step S11, using a laser dual-frequency interferometer to monitor the object plane to perform multiple deflections around the deflection axis, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle.

[0054] Step S12, using a digital speckle interferometry system to measure the first surface shape deformation corresponding to each deflection of the target observation point in the object plane.

[0055] Step S13, determining the surface deformation measurement accuracy of the digital speckle interferometry system according to the first preset angle and the first surface deformation corresponding to each deflection of the target observation point.

[0056] Since the deflection angle of the object plane is related to the surface deformation of the object plane, the present invention adopts a laser dual-frequency interferometer and a digital speckle pattern interferometry system for comparative measurement, and determines the surface deformation measurement accuracy of the digital speckle pattern interferometry system according to the measurement results, thereby realizing the accuracy evaluation of the surface deformation measurement of the digital speckle pattern interferometry system.

[0057] Figure 2 A schematic diagram of an optical path for determining the measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown. Figure 2In the optical path shown, the light emitted from the laser 1 is divided into object light and reference light by the first beam splitter prism. The object light passes through the first plane mirror 3, the second plane mirror 4, and the first beam expander 5, and then is incident on the object plane 6 (i.e., the surface of the object to be measured) at an incident angle α. The reflected light reflected by the object plane 6 passes through the second beam splitter prism 11 and is irradiated onto the image sensor 12. The reference light passes through the third plane mirror 7, the fourth plane mirror 8 with piezoelectric ceramics on the back, the second beam expander 9, the frosted glass 10, and the second beam splitter prism 11, and then is irradiated onto the image sensor 12, where it interferes with the object light irradiated onto the image sensor 12, i.e., speckle interference. By controlling the elongation of the piezoelectric ceramics behind the fourth plane mirror 8, 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). Among them, the y-axis is the yaw axis of the object plane.

[0058] It should be noted that the optical path of the digital speckle interferometry system can adopt the above Figure 2 In addition to the optical path form, other optical path deformations and component replacements of the digital speckle interferometer system also fall within the protection scope of the present disclosure.

[0059] A piezoelectric actuator (PZT) 15 is arranged behind the object plane 6 and at a preset distance from the yaw axis. The piezoelectric actuator 15 is turned on and the output of the piezoelectric actuator 15 is gradually changed so that the piezoelectric actuator 15 pushes the object plane 6 to produce a surface deformation. In this process, the object plane yaws around the yaw axis. Figure 2 In the optical path shown, a target mirror 13 is set at any position behind the object plane 6, and a dual-frequency laser interferometer 14 is set to monitor the target mirror 13. The dual-frequency laser interferometer 14 is used to monitor the target mirror 13, so that the piezoelectric actuator 15 can push the object plane 6 to deflect multiple times around the deflection axis, and the angle of each deflection is a first preset angle. Before and after each deflection of the object plane 6, the image sensor 12 collects a speckle interference image to determine the first surface shape deformation corresponding to each deflection of the target observation point in the object plane 6. The number of deflections of the object plane 6 can be determined according to actual conditions, and the present disclosure does not make specific limitations on this.

[0060] In a possible implementation, determining the surface shape deformation measurement accuracy of the digital speckle interferometry system according to a first preset angle and a first surface shape deformation corresponding to each deflection of a target observation point includes: determining a second surface shape deformation corresponding to the target observation point according to the first preset angle; and determining the surface shape deformation measurement accuracy of the digital speckle interferometry system according to a difference between the second surface shape deformation and the first surface shape deformation corresponding to each deflection of the target observation point.

[0061] In one possible implementation, the second surface deformation corresponding to the target observation point is determined according to the first preset angle, including: determining the second surface deformation by the following formula: Δω=Δθ·Δx; wherein Δω is the second surface deformation, Δθ is the first preset angle, and Δx is the distance from the target observation point to the yaw axis.

[0062] In a possible implementation, a digital speckle pattern interferometry system is used to measure a first surface shape deformation corresponding to each deflection of a target observation point in an object plane, including: for any deflection, using the digital speckle pattern interferometry system to determine the object plane phase change caused by this deflection; and determining the first surface shape deformation corresponding to the current deflection of the target observation point according to the object plane phase change.

[0063] For example, a piezoelectric actuator 15 is set at a first position behind the object plane 6, 300 mm away from the yaw axis and at the center point of the y-axis direction, and the piezoelectric actuator 15 is turned on, and the output of the piezoelectric actuator 15 is gradually changed, so that the piezoelectric actuator 15 pushes the object plane 6 to produce a surface deformation. In this process, the object plane 6 yaws around the yaw axis, and the laser dual-frequency interferometer 14 is used to monitor the target mirror 13 to determine the yaw angle of the object plane 6. When the laser dual-frequency interferometer 14 measures that the yaw angle of the object plane 6 changes by a first preset angle, the loading of the piezoelectric actuator 15 is suspended to complete a yaw. The whole process can control the object plane 6 to yaw 10 times. Among them, the first preset angle is 1 microradian (urad), and the target observation point is the second position on the object plane 6 that is 30 mm away from the yaw axis and at the center point of the y-axis direction.

[0064] Since the laser dual-frequency interferometer 14 can measure the real deflection angle (first preset angle) of each deflection, through the relationship between the deflection angle and the surface deformation: Δω=Δθ·Δx, it can be determined that the second surface deformation (real surface deformation) corresponding to each deflection of the target observation point is 30 nanometers (nm).

[0065] Before and after the object plane 6 deflects around the deflection axis by a first preset angle (before and after a primary surface shape change), a speckle interferometry image is collected by the image sensor 12, and then based on the speckle interferometry images collected before and after the deflection of the object plane 6, the object plane phase change caused by this deflection is determined, and based on the object plane phase change, a first surface shape change corresponding to the current deflection of a target observation point in the object plane 6 is determined, wherein the first surface shape change is obtained by measuring the digital speckle interferometry system.

[0066] When the first surface deformation corresponding to any deflection at the target observation point can reach the order of 30 nm, it can be determined that the measurement resolution of the surface deformation of the digital speckle interferometry system can reach 30 nm.

[0067] The surface deformation measurement accuracy of the digital speckle interferometry system is determined according to the difference between the second surface deformation (30nm) and the first surface deformation corresponding to each deflection of the target observation point in 10 deflections measured by the digital speckle interferometry system. For example, when the difference between the second surface deformation and the first surface deformation corresponding to each deflection of the target observation point measured by the digital speckle interferometry system is less than a preset threshold, it can be determined that the surface deformation measurement accuracy of the digital speckle interferometry system is high. The first preset angle and the position of the target observation point are related to the resolution of the digital speckle interferometry system, and the specific values ​​can be determined according to actual conditions, and the present disclosure does not make specific limitations on this.

[0068] A laser dual-frequency interferometer is used to monitor the object surface to perform multiple deflections around a deflection axis, wherein the angle of each deflection of the object surface around the deflection axis is a first preset angle; a digital speckle pattern interferometry system is used to measure a first surface shape deformation corresponding to each deflection of a target observation point in the object surface; and the surface shape deformation measurement accuracy of the digital speckle pattern interferometry system is determined according to the first preset angle and the first surface shape deformation corresponding to each deflection of the target observation point, thereby realizing the accuracy evaluation of the surface shape deformation measurement of the digital speckle pattern interferometry system, and further realizing the calibration and correction of the digital speckle pattern interferometry system effectively when measuring the surface shape deformation.

[0069] Figure 3 A flow chart showing a method for determining the measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown. Figure 3 As shown, the method may include:

[0070] Step S31 , using a laser dual-frequency interferometer to monitor the object plane to perform multiple rolls around the roll axis, wherein the angle of each roll of the object plane around the roll axis is a second preset angle.

[0071] Step S32 , using a digital speckle interferometry system to measure the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point in the object plane.

[0072] Step S33, determining the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second preset angle and the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point.

[0073] Since the rolling angle of the object surface when rolling is related to the in-plane deformation of the object surface, the present invention adopts a laser dual-frequency interferometer and a digital speckle pattern interferometry system for comparative measurement, and determines the in-plane deformation measurement accuracy of the digital speckle pattern interferometry system based on the measurement results, thereby realizing the accuracy evaluation of the in-plane deformation measurement of the digital speckle pattern interferometry system.

[0074] Figure 4 A schematic diagram of an optical path for determining the measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure is shown. Figure 4 In the optical path shown, the digital speckle interferometry system has an optical path structure of dual-beam illumination. The light emitted from the laser 1 is divided into two paths by the first beam splitter prism 2 and the second beam splitter prism 3: the first light path and the second light path. The first light path passes through the first plane mirror 7 with a piezoelectric ceramic 5 on the back and the first beam expander 8 and is incident on the object plane 10 at an incident angle α. The second light path passes through the second plane mirror 6 and the second beam expander 9 and is incident on the object plane 10 at an incident angle β. The first light path and the second light path, which are diffusely reflected by the object plane 10, are irradiated onto the image sensor 11, and interference occurs on the image sensor 11, i.e., speckle interference. By controlling the elongation of the piezoelectric ceramic 5 behind the first plane mirror 7, multiple additional optical paths are introduced into the optical path where the first light path 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). Among them, the z axis is the roll axis of the object plane.

[0075] It should be noted that the optical path of the digital speckle interferometry system can adopt the above Figure 2 In addition to the optical path form, other optical path deformations and component replacements of the digital speckle interferometer system also fall within the protection scope of the present disclosure.

[0076] A piezoelectric actuator (PZT) 14 is set at the center position behind the object plane 10, and the piezoelectric actuator 14 is turned on, and the output of the piezoelectric actuator 14 is gradually changed, so that the piezoelectric actuator 14 pushes the object plane 10 to produce in-plane deformation. In this process, the object plane 10 rolls around the roll axis. Figure 4 In the optical path shown, a target mirror 12 is set at any position behind the object plane 10, and a dual-frequency laser interferometer 13 is set to monitor the target mirror 12. The dual-frequency laser interferometer 13 is used to monitor the target mirror 12, so that the piezoelectric actuator 14 can push the object plane 10 to roll around the roll axis for multiple times, and the angle of each roll is a second preset angle. Before and after each roll of the object plane 10, the image sensor 11 collects a speckle interference image to determine the first surface shape deterioration corresponding to each deflection of the first target observation point and the second target observation point in the object plane 10. The number of rolls of the object plane 10 can be determined according to actual conditions, and the present disclosure does not make specific limitations on this.

[0077] In a possible implementation manner, determining the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second preset angle and the first in-plane deformation difference corresponding to each rolling of the first target observation point and the second target observation point includes: determining the second in-plane deformation difference corresponding to the first target observation point and the second target observation point according to the second preset angle; and determining the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second in-plane deformation difference and the difference between the first in-plane deformation difference corresponding to each rolling of the first target observation point and the second target observation point.

[0078] In one possible implementation, determining the second in-plane deformation difference corresponding to the first target observation point and the second target observation point according to the second preset angle includes: determining the horizontal distance between the first target observation point and the second target observation point; and determining the second in-plane deformation difference according to the product of the second preset angle and the horizontal distance.

[0079] In a possible implementation, a digital speckle interferometry system is used to measure a first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in an object plane, including: for any roll, using the digital speckle interferometry system to determine the object plane phase change caused by this roll; and determining, according to the object plane phase change, the first in-plane deformation difference corresponding to this roll of the first target observation point and the second target observation point.

[0080] For example, a piezoelectric actuator 14 is set at the center position behind the object plane 10 (where the roll axis is located), the piezoelectric actuator 14 is turned on, and the output of the piezoelectric actuator 14 is gradually changed, so that the piezoelectric actuator 14 pushes the object plane 10 to produce in-plane deformation. In this process, the object plane 10 rolls around the roll axis, and the laser dual-frequency interferometer 13 is used to monitor the target mirror 12 to determine the roll angle of the object plane 10. When the laser dual-frequency interferometer 13 measures that the roll angle of the object plane 10 changes by a second preset angle, the loading of the piezoelectric actuator 14 is suspended to complete a roll. The whole process can control the object plane 10 to undergo 10 in-plane deformations. Among them, the second preset angle is 0.2urad, the first target observation point and the second target observation point are symmetrically distributed relative to the roll axis, and the horizontal distance is 250mm.

[0081] Since the laser dual-frequency interferometer 13 can measure the true roll angle (second preset angle) of each roll, the relationship between the roll angle and the in-plane deformation is: Δu=Δσ·Δy, that is, based on the product of the second preset angle 0.2urad and the horizontal distance 250mm between the first target observation point and the second target observation point, it can be determined that the second in-plane deformation difference of 50nm corresponding to the roll of the first target observation point and the second target observation point after each roll.

[0082] Before and after the piezoelectric actuator pushes the object plane 10 to roll around the roll axis by a second preset angle (before and after an in-plane deformation), a speckle interferometer image is collected by the image sensor 11, and then the object plane phase change caused by this deformation is determined based on the speckle interferometer image collected before and after the deformation of the object plane 10, and the first in-plane deformation difference corresponding to the current roll of the first target observation point and the second target observation point in the object plane 10 is determined based on the object plane phase change, wherein the first in-plane deformation difference is measured based on the digital speckle interferometer system.

[0083] When the first in-plane deformation difference can reach the order of 50 nm, it can be determined that the measurement resolution of the in-plane deformation of the digital speckle interferometry system can reach 50 nm.

[0084] The in-plane deformation measurement accuracy of the digital speckle interferometry system is determined according to the difference between the second in-plane deformation difference (50nm) and the first in-plane deformation difference corresponding to each deflection measured by the digital speckle interferometry system. For example, when the difference between the second in-plane deformation difference and the first surface shape difference corresponding to each roll measured by the digital speckle interferometry system is less than a preset threshold, it can be determined that the in-plane deformation measurement accuracy of the digital speckle interferometry system is high. The size of the second preset angle, and the positions of the first target observation point and the second target observation point are related to the in-plane deformation measurement resolution of the digital speckle interferometry system. The specific values ​​can be determined according to actual conditions, and the present disclosure does not make specific limitations on this.

[0085] A laser dual-frequency interferometer is used to monitor the object surface to perform multiple rolls around the roll axis, wherein the angle of each roll of the object surface around the roll axis is a second preset angle; a digital speckle pattern interferometry system is used to measure the first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object surface; and the in-plane deformation measurement accuracy of the digital speckle pattern interferometry system is determined according to the second preset angle and the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point, so that the accuracy evaluation of the in-plane deformation measurement of the digital speckle pattern interferometry system can be achieved, and further, the digital speckle pattern interferometry system can be effectively calibrated and calibrated during the in-plane deformation measurement.

[0086] It can be understood that the above-mentioned various method embodiments mentioned in the present disclosure can be combined with each other to form a combined embodiment without violating the principle logic. Due to space limitations, the present disclosure will not repeat them. It can be understood by those skilled in the art that in the above-mentioned method of the specific implementation method, the specific execution order of each step should be determined according to its function and possible internal logic.

[0087] In addition, the present disclosure also provides a device for determining the measurement accuracy of a digital speckle interferometer system, an electronic device, a computer-readable storage medium, and a program, all of which can be used to implement any method for determining the measurement accuracy of a digital speckle interferometer system provided by the present disclosure. The corresponding technical solutions and descriptions are referred to in the corresponding records of the method part and will not be repeated here.

[0088] Figure 5 FIG. 1 is a block diagram showing a device for determining measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure. Figure 5 As shown, the device 50 includes:

[0089] A deflection module 51, used for monitoring the object plane to perform multiple deflections around the deflection axis using a laser dual-frequency interferometer, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle;

[0090] A surface deformation measurement module 52 is used to measure a first surface deformation corresponding to each deflection of a target observation point in the object plane by using a digital speckle interferometry system;

[0091] The first determination module 53 is used to determine the surface deformation measurement accuracy of the digital speckle interferometry system according to the first preset angle and the first surface deformation corresponding to each deflection of the target observation point.

[0092] In a possible implementation, the first determining module 53 includes:

[0093] A first determination submodule, used to determine a second surface deformation corresponding to a target observation point according to a first preset angle;

[0094] The second determination submodule is used to determine the surface deformation measurement accuracy of the digital speckle interferometry system according to the difference between the second surface deformation and the first surface deformation corresponding to each deflection of the target observation point.

[0095] In a possible implementation manner, the first determining submodule is specifically configured to:

[0096] The second surface deformation is determined by the following formula:

[0097] Δω=Δθ·Δx;

[0098] Wherein, Δω is the second surface deformation, Δθ is the first preset angle, and Δx is the distance from the target observation point to the yaw axis.

[0099] In a possible implementation, the surface deformation measurement module 52 is specifically used for:

[0100] For any deflection, the digital speckle interferometry system is used to determine the object plane phase change caused by the deflection;

[0101] According to the object plane phase change, the first surface shape deformation corresponding to the current deflection of the target observation point is determined.

[0102] Figure 6 FIG. 1 is a block diagram showing a device for determining measurement accuracy of a digital speckle interferometry system according to an embodiment of the present disclosure. Figure 6 As shown, the device 60 includes:

[0103] A rolling module 61, used for monitoring the object surface to perform multiple rollings around the rolling axis using a laser dual-frequency interferometer, wherein the angle of each rolling of the object surface around the rolling axis is a second preset angle;

[0104] An in-plane deformation measurement module 62, configured to measure a first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object plane by using a digital speckle interferometry system;

[0105] The second determination module 63 is used to determine the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second preset angle and the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point.

[0106] In a possible implementation, the second determining module 63 includes:

[0107] A third determination submodule, configured to determine a second in-plane deformation difference corresponding to the first target observation point and the second target observation point according to a second preset angle;

[0108] The fourth determination submodule is used to determine the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second in-plane deformation difference and the difference between the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point.

[0109] In a possible implementation manner, the third determining submodule is specifically configured to:

[0110] Determine the horizontal distance between the first target observation point and the second target observation point;

[0111] The second in-plane deformation difference is determined according to the product of the second preset angle and the horizontal distance.

[0112] In a possible implementation, the in-plane deformation measurement module 62 is specifically used for:

[0113] For any roll, the digital speckle interferometry system is used to determine the phase change of the object surface caused by this roll;

[0114] According to the phase change of the object plane, the first in-plane deformation difference corresponding to the current roll of the first target observation point and the second target observation point is determined.

[0115] The embodiment of the present disclosure also provides a computer-readable storage medium, on which computer program instructions are stored, and when the computer program instructions are executed by a processor, the above method is implemented. The computer-readable storage medium may be a non-volatile computer-readable storage medium.

[0116] An embodiment of the present disclosure further proposes an electronic device, comprising: a processor; and a memory for storing instructions executable by the processor; wherein the processor is configured to call the instructions stored in the memory to execute the above method.

[0117] The embodiments of the present disclosure also provide a computer program product, including computer readable codes. When the computer readable codes are executed on a device, a processor in the device executes instructions for implementing the method for determining the measurement accuracy of a digital speckle interferometry system provided in any of the above embodiments.

[0118] The disclosed embodiment also provides another computer program product for storing computer-readable instructions, which, when executed, enables the computer to perform the operations of the method for determining the measurement accuracy of the digital speckle interferometry system provided in any of the above embodiments.

[0119] Those of ordinary skill 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 to be beyond the scope of this disclosure.

[0120] 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 disclosure, 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, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present disclosure. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM), random access memory (RAM), disk or optical disk, etc., various media that can store program codes.

[0121] In the embodiments of the device, method, system, etc. disclosed in the present invention, 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 invention. At the same time, in the above description of the specific embodiments of the present invention, 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.

[0122] It should be emphasized that the term “include / comprises” when used herein refers to the presence of features, elements, steps or components, but does not exclude the presence or addition of one or more other features, elements, steps or components.

[0123] The embodiments of the present disclosure have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or technical improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.

Claims

1. A method for determining the measurement accuracy of a digital speckle interferometry system, characterized in that: include: A laser dual-frequency interferometer is used to monitor the object plane to perform multiple deflections around the deflection axis, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle; Using a digital speckle interferometry system to measure the first surface shape deformation corresponding to each deflection of a target observation point in the object plane; Determining a second surface deformation corresponding to the target observation point according to the first preset angle; The second surface deformation is determined by the following formula: Δω=Δθ·Δx, Wherein, Δω is the second surface deformation, Δθ is the first preset angle, and Δx is the distance from the target observation point to the yaw axis; The surface deformation measurement accuracy of the digital speckle interferometry system is determined according to the difference between the second surface deformation and the first surface deformation corresponding to each deflection of the target observation point.

2. The method according to claim 1, characterized in that The method of using a digital speckle interferometry system to measure the first surface deformation corresponding to each deflection of a target observation point in the object plane comprises: For any deflection, the digital speckle interferometry system is used to determine the object plane phase change caused by the deflection; According to the object plane phase change, the first surface shape deformation corresponding to the current deflection of the target observation point is determined.

3. A method for determining the measurement accuracy of a digital speckle interferometry system, characterized in that: include: A laser dual-frequency interferometer is used to monitor the object plane to perform multiple rolls around the roll axis, wherein the angle of each roll of the object plane around the roll axis is a second preset angle; Using a digital speckle interferometry system to measure a first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object plane, wherein the first target observation point and the second target observation point are symmetrically distributed relative to the roll axis; Determine, according to the second preset angle, a second in-plane deformation difference corresponding to the first target observation point and the second target observation point; Determining a horizontal distance between the first target observation point and the second target observation point; determining the second in-plane deformation difference according to the product of the second preset angle and the horizontal distance; The in-plane deformation measurement accuracy of the digital speckle interferometry system is determined according to the second in-plane deformation difference and the difference between the first in-plane deformation differences corresponding to each rolling of the first target observation point and the second target observation point.

4. The method according to claim 3, characterized in that The method of using a digital speckle interferometry system to measure the first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object plane comprises: For any roll, the digital speckle interferometry system is used to determine the object plane phase change caused by the roll; According to the object plane phase change, a first in-plane deformation difference corresponding to the current roll of the first target observation point and the second target observation point is determined.

5. A device for determining the measurement accuracy of a digital speckle interferometry system, characterized in that: include: A deflection module, used for monitoring the object plane to perform multiple deflections around a deflection axis using a laser dual-frequency interferometer, wherein the angle of each deflection of the object plane around the deflection axis is a first preset angle; A surface deformation measurement module, used for measuring a first surface deformation corresponding to each deflection of a target observation point in the object plane by using a digital speckle interferometry system; Determining a second surface deformation corresponding to the target observation point according to the first preset angle; The second surface deformation is determined by the following formula: Δω=Δθ·Δx, Wherein, Δω is the second surface deformation, Δθ is the first preset angle, and Δx is the distance from the target observation point to the yaw axis; The first determination module is used to determine the surface deformation measurement accuracy of the digital speckle interferometry system according to the difference between the second surface deformation and the first surface deformation corresponding to each deflection of the target observation point.

6. A device for determining the measurement accuracy of a digital speckle interferometry system, characterized in that: include: A rolling module, used for monitoring the object plane to perform multiple rollings around the rolling axis by using a laser dual-frequency interferometer, wherein the angle of each rolling of the object plane around the rolling axis is a second preset angle; an in-plane deformation measurement module, configured to measure a first in-plane deformation difference corresponding to each roll of a first target observation point and a second target observation point in the object plane using a digital speckle interferometry system, wherein the first target observation point and the second target observation point are symmetrically distributed relative to the roll axis; Determine, according to the second preset angle, a second in-plane deformation difference corresponding to the first target observation point and the second target observation point; Determining a horizontal distance between the first target observation point and the second target observation point; determining the second in-plane deformation difference according to the product of the second preset angle and the horizontal distance; The second determination module is used to determine the in-plane deformation measurement accuracy of the digital speckle interferometry system according to the second in-plane deformation difference and the difference between the first in-plane deformation difference corresponding to each roll of the first target observation point and the second target observation point.

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