Large-angle two-dimensional fast mirror angle calibration device, system and method

Abstract

This invention provides a large-angle two-dimensional fast reflector angle calibration device, system, and method based on a coaxial optical path. The device includes an opto-autocollimator, a fast reflector, a comprehensive adjustment base, and a two-degree-of-freedom rotary table. The opto-autocollimator is mounted on the comprehensive adjustment base, which includes a fine-tuning base and a coarse-tuning base. The fine-tuning base is used to adjust the yaw and pitch angles of the opto-autocollimator, and the coarse-tuning base is used to adjust the position of the opto-autocollimator. The two-degree-of-freedom rotary table includes a first rotation mechanism and a second rotation mechanism. The fast reflector is mounted on the second rotation mechanism, and the second rotation mechanism is mounted on the first rotation mechanism. The two deflection axes on the fast reflector are aligned coaxially with the first and second rotation mechanisms. The first rotation mechanism drives the fast reflector to rotate around the X-axis, and the second rotation mechanism drives the fast reflector to rotate around the Y-axis.

Description

Technical Field

[0001] This invention belongs to the field of fast reflector mirror calibration technology, specifically relating to a large-angle two-dimensional fast reflector angle calibration device, system and method based on a coaxial optical path. Background Technology

[0002] Fast Steering Mirrors (FSMs) are precision optoelectronic devices used to adjust and stabilize the line of sight or beam pointing of an optical system. They have advantages such as compact structure, fast response speed, high operating bandwidth and high pointing accuracy, and have been widely used in many fields such as space optical communication, astronomical telescopes, adaptive optics imaging, precision tracking and laser weapons.

[0003] Fast-reflecting mirrors are characterized by a limited deflection angle range but high angle adjustment accuracy. Their angle calibration methods typically employ techniques such as direct measurement with an autocollimator, optical interferometry, or spot position-sensitive detection to obtain the actual value of the mirror angle. This value is then combined with the output from the fast-reflecting mirror system's built-in position sensor, and a calibration curve is obtained through nonlinear fitting or interpolation methods, thus completing the angle calibration. Most commercial fast-reflecting mirror systems use this method to achieve high-precision angle control, with typical measurement accuracy reaching the micro-arc level.

[0004] As optoelectronic systems evolve towards wider range, higher mobility, and higher precision, the demand for large-angle applications of fast reflectors is becoming increasingly prominent. Increasing the deflection angle of a fast reflector can effectively expand the system's pointing coverage and effective field of view, reduce platform-level coarse pointing actions and target switching time, thereby improving target acquisition probability and mission flexibility. However, most existing angle calibration methods are designed for small-angle applications. In large-angle scenarios, they are often limited by factors such as limited measurement range and insufficient optical path coverage, making it difficult to meet the high-precision calibration requirements under large-range deflection conditions. Furthermore, balancing calibration efficiency and overall accuracy consistency over a large travel range is a key aspect that urgently needs optimization in existing technologies. Therefore, developing an angle calibration method and system that combines large-angle adaptability, high calibration accuracy, and high repeatability stability is of great significance for improving the overall performance of large-angle fast reflectors. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this invention is to provide a large-angle two-dimensional fast reflector angle calibration device, system, and method based on a coaxial optical path.

[0006] According to a first aspect of the present invention, a large-angle two-dimensional fast reflector angle calibration device based on a coaxial optical path includes an opto-autocollimator, a fast reflector, a comprehensive adjustment base, and a two-degree-of-freedom rotary table. The opto-autocollimator is mounted on the comprehensive adjustment base, which includes a fine-tuning base and a coarse-tuning base. The fine-tuning base is used to adjust the yaw angle and pitch angle of the opto-autocollimator, and the coarse-tuning base is used to adjust the position and attitude of the opto-autocollimator. The two-degree-of-freedom rotary table includes a first rotation mechanism and a second rotation mechanism. The fast reflector is mounted on the second rotation mechanism, and the second rotation mechanism is mounted on the first rotation mechanism. The two deflection axes on the fast reflector are aligned with the coaxiality of the first rotation mechanism and the second rotation mechanism. The first rotation mechanism is used to drive the fast reflector to rotate around the X-axis, and the second rotation mechanism is used to drive the fast reflector to rotate around the Y-axis. The photoelectric autocollimator is equipped with a first host computer software, which is used to obtain the angular deviation values ​​(x, y) of the reflected light of the photoelectric autocollimator relative to the emitted light axis in the X and Y axes within the field of view. The two-degree-of-freedom rotary table is equipped with a second host computer software, which is used to control the two-degree-of-freedom rotary table to rotate the target angle (X, Y) in the X and Y axis directions. The fast reflector has a built-in dual-axis angle feedback acquisition system, which can acquire the angle feedback signals of the fast reflector in the X and Y axes and output the corresponding feedback AD codes. .

[0007] According to a second aspect of the present invention, a method for calibrating the angle of a large-angle two-dimensional fast reflector based on a coaxial optical path, employing the apparatus of the first aspect, the method comprising: Step S1: Perform zero-position calibration on the fast reflector and the photoelectric autocollimator, ensuring that the optical axis of the photoelectric autocollimator passes perpendicularly through the central region of the fast reflector surface. Based on this, conduct a joint trial run of the photoelectric autocollimator and the two-degree-of-freedom rotary table. By recording the correspondence between the readings of the two systems, complete the determination and differentiation of the positive angle direction between the first and second host computer software. Step S2: Control the first and second rotation mechanisms of the two-degree-of-freedom rotary table to perform fixed-point driving, so that the two-degree-of-freedom rotary table is positioned to the target angle pose (X, Y), wherein the target angle pose (X, Y) should match the compensation deflection capability of the fast reflector; Step S3: Drive the fast steering mirror to perform fixed-point deflection in the direction opposite to the deflection direction of the two-degree-of-freedom rotating stage to achieve angle compensation. When the reflected light of the autocollimator reflected by the fast steering mirror can be received by the photoelectric autocollimator again and a cursor close to the coordinate zero position and with stable reading can be detected in the first upper computer software of the photoelectric autocollimator, record the AD code at this time and the readings (x, y) of the first upper computer software; Step S4: According to the target angle pose (X, Y) and the readings (x, y) of the first upper computer software, calculate the actual rotation angle of the fast steering mirror at this time ; Repeat steps S2 to S4 to obtain a sufficient amount of data pairs covering the entire angle range of the fast steering mirror; Step S5: Perform non-linear fitting or interpolation calculation on the actual rotation angle of the fast steering mirror and the feedback output AD code to complete the two-dimensional angle calibration of the full range of the fast steering mirror.

[0008] Preferably, in step S1, the zero position calibration between the fast steering mirror and the photoelectric autocollimator is completed in the following manner: After the fast steering mirror and the two-degree-of-freedom rotating stage are initially returned to zero, place the laser finder supporting the photoelectric autocollimator at the front end of the autocollimator, and adjust the spatial position and azimuth attitude of the autocollimator through the coarse adjustment base to make the outgoing light spot of the laser finder fall on the central area of the fast steering mirror surface and make the outgoing light and the reflected light reach a roughly coincident state, thereby completing the coarse adjustment of the optical axis of the autocollimator; then remove the laser finder. At this time, a cursor signal can be observed in the upper computer software of the autocollimator, and move the cursor to the coordinate zero position through the fine adjustment base to complete the fine adjustment of the optical axis.

[0009] Preferably, in step S1, the determination and distinction of the positive angle direction between the first upper computer software and the second upper computer software are completed in the following manner: Before the zero position calibration in step S1 is completed and the formal calibration process starts, keep the fast steering mirror not deflected, control the two-degree-of-freedom rotating stage to run to a set of small angle poses (X0, Y0). The specific value range of the small angle is limited to not exceeding the field of view range of the first upper computer software, so that the reflected light of the photoelectric autocollimator can still fall within the field of view acquisition range of the first upper computer software, and record the readings (x0, y0) of the first upper computer software in this pose. Subsequently, complete the determination and distinction of the positive angle direction by comparing the positive and negative sign relationships between x0 and X0, and y0 and Y0.

[0010] Preferably, in step S4, the calculation of the actual rotation angle of the fast steering mirror is as follows: Based on the results of the joint trial run of the photoelectric autocollimator and the two-degree-of-freedom rotary table in step S1, if the positive and negative signs of x0 and X0, and y0 and Y0 are consistent, then the formula for calculating the actual rotation angle of the fast reflector is uniformly defined as follows:

[0011]

[0012] If the signs of any of the terms x0 and X0, or y0 and Y0 are opposite, then the plus sign in the corresponding formula should be changed to a minus sign.

[0013] Preferably, the entire dual-axis angular range is covered by the following path: the rotation angle of the two-degree-of-freedom rotary table is made to range from (+X) max , +Y max The transition proceeds stepwise from (±dx, 0) or (0, ±dy) to (-X). max , -Y max ).

[0014] Preferably, the path is a continuous bending path in the horizontal or vertical direction; wherein, the continuous bending path in the horizontal direction is scanned back and forth with a step amount dx and then progressively advances row by row with a step amount dy; the continuous bending path in the vertical direction is scanned back and forth with a step amount dy and then progressively advances column by column with a step amount dx; the path gradually covers the entire dual-axis angle range.

[0015] According to a third aspect of the present invention, a large-angle two-dimensional fast reflector angle calibration system based on a coaxial optical path, employing the apparatus of the first aspect, wherein the method includes: Module M1: Performs zero-position calibration on the fast reflector and photoelectric autocollimator, ensuring that the optical axis of the photoelectric autocollimator passes perpendicularly through the central region of the fast reflector surface. Based on this, a joint trial run is conducted on the photoelectric autocollimator and the two-degree-of-freedom rotary table. By recording the correspondence between the readings of the two systems, the positive angle determination and differentiation between the first and second host computer software are completed. Module M2: Controls the first and second rotation mechanisms of the two-degree-of-freedom rotary table to perform fixed-point driving, so that the two-degree-of-freedom rotary table is positioned to the target angle pose (X, Y), wherein the target angle pose (X, Y) should match the compensation deflection capability of the fast reflector; Module M3: Drives the fast-reflecting mirror to deflect at a fixed point in the opposite direction to the deflection direction of the two-degree-of-freedom rotary table to achieve rotation angle compensation. When the reflected light from the autocollimator after being reflected by the fast-reflecting mirror can be re-received by the photoelectric autocollimator, and when the cursor that is close to the coordinate zero position and can be stably read is detected in the first upper-level software of the photoelectric autocollimator, the AD code at this time is recorded. And the readings (x, y) from the first host computer software; Module M4: Calculate the actual rotation angle of the fast steering mirror at this time based on the target angular position and orientation (X, Y) and the readings (x, y) of the first host computer software. ; Trigger modules M2 to M4 repeatedly to obtain a sufficient number of data pairs covering the entire angular range of the fast steering mirror. Module M5: Perform non-linear fitting or interpolation calculations on the actual rotation angle of the fast steering mirror and the feedback output AD code to complete the two-dimensional angular calibration of the entire range of the fast steering mirror.

[0016] Preferably, in module M1, the zero position calibration between the fast steering mirror and the photoelectric autocollimator is completed as follows: After the fast steering mirror and the two-degree-of-freedom rotary table return to zero initially, place the laser finder supporting the photoelectric autocollimator at the front end of the autocollimator. Adjust the spatial position and azimuth attitude of the autocollimator through the coarse adjustment base so that the outgoing light spot of the laser finder falls within the central area of the mirror surface of the fast steering mirror, and make the outgoing light and the reflected light reach a roughly coincident state, thereby completing the coarse adjustment of the optical axis of the autocollimator. Subsequently, remove the laser finder. At this time, the cursor signal can be observed in the host computer software of the autocollimator. Move the cursor to the zero position of the coordinate axis through the fine adjustment base to complete the fine adjustment of the optical axis.

[0017] Preferably, in module M1, the determination and distinction of the positive angular direction between the first host computer software and the second host computer software are completed as follows: [[ID=ID=19]] Before the zero position calibration of module M1 is completed and the formal calibration process starts, keep the fast steering mirror not deflected, control the two-degree-of-freedom rotary table to run to a set of small angular positions and orientations (X0, Y0). The specific value range of the small angle is limited to not exceeding the field of view range of the first host computer software, so that the reflected light of the photoelectric autocollimator can still fall within the field of view acquisition range of the first host computer software, and record the readings (x0, y0) of the first host computer software at this position and orientation. Subsequently, complete the determination and distinction of the positive angular direction by comparing the positive and negative sign relationships between x0 and X0, and y0 and Y0.

[0018] Preferably, in module M4, the calculation of the actual rotation angle of the fast steering mirror is as follows: According to the combined test run results of the photoelectric autocollimator and the two-degree-of-freedom rotary table in module M1, if the positive and negative signs of x0 and X0, and y0 and Y0 are all the same, uniformly stipulate that the actual rotation angle calculation formula of the fast steering mirror is:

[0019]

[0020] If the signs of any of the terms x0 and X0, or y0 and Y0 are opposite, then the plus sign in the corresponding formula should be changed to a minus sign.

[0021] The system is characterized in that it covers the entire dual-axis angular range via the following path: the rotation angle of the two-degree-of-freedom rotary table is adjusted from (+X) max , +Y max The transition proceeds stepwise from (±dx, 0) or (0, ±dy) to (-X). max , -Y max ).

[0022] Compared with the prior art, the present invention has the following beneficial effects: The present invention relates to a large-angle two-dimensional fast-reflecting mirror angle calibration device, system, and method based on a coaxial optical path. This device combines a high-precision two-degree-of-freedom rotary stage with a photoelectric autocollimator, supplemented by fine-tuning and coarse-tuning mechanisms. The high-precision two-degree-of-freedom rotary stage converts the mirror angle after a large-angle fixed-point deflection of the fast-reflecting mirror into a small deflection relative to the optical axis of the photoelectric autocollimator. By integrating the rotary stage readings, autocollimator readings, and the AD code feedback output from the fast-reflecting mirror, high-precision angle calibration of the fast-reflecting mirror under large-angle deflection conditions is achieved. This system and method effectively overcome the technical bottleneck of traditional angle calibration schemes, which are limited in range and unable to meet the high-precision calibration requirements of large-angle fast-reflecting mirrors. The system has a simple structure and is easy to assemble; the method is easy to implement and offers high calibration accuracy and good repeatability. Attached Figure Description

[0023] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram of a large-angle two-dimensional fast reflector angle calibration system based on a coaxial optical path in an embodiment of the present invention; Figure 2 This is a schematic diagram of the data acquisition interface of the host computer software for the photoelectric autocollimator in an embodiment of the present invention; Figure 3 This is a schematic diagram of the linkage between various components of the system during a large-angle calibration process provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the pose translation path of a two-degree-of-freedom rotary table provided in an embodiment of the present invention; In the figure, 1 is the first rotating mechanism, 2 is the second rotating mechanism, 3 is the fast reflector, 4 is the photoelectric autocollimator, 5 is the fine-tuning base, and 6 is the coarse-tuning base. Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0025] This embodiment provides a large-angle two-dimensional fast-reflecting mirror angle calibration device based on a coaxial optical path and its application method, such as... Figure 1 As shown, the device includes an opto-autocollimator 4, a fast reflector 3, a comprehensive adjustment base, and a two-degree-of-freedom rotary table. The opto-autocollimator 4 is mounted on the comprehensive adjustment base, which includes a fine-tuning base 5 and a coarse-tuning base 6. The fine-tuning base 5 is used to adjust the yaw and pitch angles of the opto-autocollimator 4. The coarse-tuning base 6 has two translational degrees of freedom X and Y and one rotational degree of freedom about the X-axis, and is used to adjust the position and attitude of the opto-autocollimator 4. The two-degree-of-freedom rotary table includes a first rotation mechanism 1 and a second rotation mechanism 2. The fast-reflecting mirror 3 is mounted on the second rotation mechanism 2, and the second rotation mechanism 2 is mounted on the first rotation mechanism 1. The two deflection axes on the fast-reflecting mirror 3 are aligned coaxially with the first rotation mechanism 1 and the second rotation mechanism 2. The first rotation mechanism 1 drives the fast-reflecting mirror 3 to rotate around the X-axis, and the second rotation mechanism 2 drives the fast-reflecting mirror 3 to rotate around the Y-axis. Figure 2 As shown, the photoelectric autocollimator 4 is equipped with a first host computer software. The first host computer software is used to obtain the angular deviation values ​​(x, y) of the reflected light of the photoelectric autocollimator relative to the emitted light axis in the X and Y axes within the field of view. The software resolution is 0.1″ and the test accuracy is ±0.5″. The two-degree-of-freedom rotary table is equipped with a second host computer software. The drive motors of the first rotation mechanism 1 and the second rotation mechanism 2 both adopt a circular grating closed-loop feedback scheme. The second host computer software is used to control the two-degree-of-freedom rotary table to rotate the target angle (X, Y) in the X and Y axis directions, with a minimum step of 0.001° and a repeatability of 0.002°. The fast reflector 3 employs a voice coil motor drive scheme, enabling dual-axis mechanical deflection of ±10º. The fast reflector 3 incorporates a dual-axis angle feedback acquisition system based on a high-precision photoelectric detector. This system acquires angle feedback signals from the fast reflector 3 along the X and Y axes and outputs corresponding feedback AD codes. .

[0026] Based on the above device, a method for calibrating the angle of a large-angle two-dimensional fast reflector is provided, the method comprising: Step S1: Zero calibration is performed on the fast steering mirror 3 and the photoelectric autocollimator 4 so that the optical axis of the photoelectric autocollimator 4 vertically passes through the center area of the mirror surface of the fast steering mirror 3. On this basis, the photoelectric autocollimator 4 and the two-degree-of-freedom rotating table (the first rotating mechanism 1 and the second rotating mechanism 2) are jointly tested. By recording the corresponding relationship of the readings of the two, the determination and distinction of the positive direction of the angle between the first host computer software and the second host computer software are completed; Step S2: Control the first rotating mechanism 1 and the second rotating mechanism 2 of the two-degree-of-freedom rotating table to perform fixed-point driving so that the two-degree-of-freedom rotating table is positioned at the target angular pose (X, Y), where the target angular pose (X, Y) should match the compensation deflection ability of the fast steering mirror; Step S3: As Figure 3 shown, drive the fast steering mirror 3 to perform fixed-point deflection in the direction opposite to the deflection direction of the two-degree-of-freedom rotating table to achieve angle compensation. When the autocollimator reflected light reflected by the mirror surface of the fast steering mirror 3 can be received by the photoelectric autocollimator 4 again, and a cursor that is close to the coordinate zero position and can be stably read is detected in the first host software of the photoelectric autocollimator 4, record the AD code at this time and the readings (x, y) of the first host computer software; Step S4: According to the target angular pose (X, Y) and the readings (x, y) of the first host computer software, calculate the actual rotation angle of the fast steering mirror 3 at this time ; Repeat steps S2~S4 to obtain a sufficient amount of data pairs covering the entire angular range of the fast steering mirror 3; Step S5: Perform non-linear fitting or interpolation calculation on the actual rotation angle of the fast steering mirror 3 and the feedback output AD code to complete the full-range two-dimensional angle calibration of the fast steering mirror 3.

[0027] In this embodiment, in step S1, the zero calibration between the fast steering mirror 3 and the photoelectric autocollimator 4 is completed by the following method: After the fast steering mirror 3 and the two-degree-of-freedom rotating table (the first rotating mechanism 1 and the second rotating mechanism 2) are initially returned to zero, place the laser finder supporting the photoelectric autocollimator 4 at the front end of the autocollimator. Adjust the spatial position and azimuth attitude of the autocollimator through the coarse adjustment base 6 so that the laser spot emitted by the laser finder falls on the center area of the mirror surface of the fast steering mirror 3, and make the emitted light and the reflected light reach a roughly coincident state, thereby completing the coarse adjustment of the optical axis of the autocollimator; then remove the laser finder. At this time, a cursor signal can be observed in the host computer software of the autocollimator. Move the cursor to the zero position of the coordinate axis through the fine adjustment base 5 to complete the fine adjustment of the optical axis.

[0028] In this embodiment, before the zero-position calibration is completed in step S1 and the formal calibration process begins, the fast reflector 3 is kept unrotated, and the two-degree-of-freedom rotary table is controlled to run to a certain set of small angle poses (X0, Y0). The range of values ​​for this small angle is specifically limited to no more than Figure 2 The field of view range of the first host computer software is set to no more than (±1650″, ±1350″), ensuring that the reflected light from the photoelectric autocollimator 4 still falls within the field of view acquisition range of the first host computer software, and the readings (x0, y0) of the first host computer software in this pose are recorded. The experiment shows that the positive and negative signs of x0 and X0, and y0 and Y0 are consistent.

[0029] In this embodiment, in step S3, the fast reflector 3 is driven by the control board with constant current.

[0030] In this embodiment, the actual rotation angle of the fast-reflecting mirror 3 is calculated in step S4 as follows:

[0031]

[0032] In this embodiment, as Figure 4 As shown, the two-degree-of-freedom rotary table is driven to cover the entire dual-axis angle calibration range of the fast reflector 3 via the following transverse continuous bending path: By (+X) max , +Y max The algorithm iterates through multiple steps in increments of (-dx, 0) until it reaches (-X). max , +Y max ); By (-X) max , +Y max Progress in single steps from (0, -dy) to (-X). max , +Y ymax - dy); By (-X) max , +Y ymax - dy) progresses in multiple steps with a step size of (+dx, 0) until (+X) max , +Y ymax - dy); By (+X) max , +Y ymax -dy) progresses step by step in increments of (0, -dy) until (+X) max , +Y ymax - 2dy); ... By analogy, the entire dual-axis angle range is gradually covered according to the continuous bending path.

[0033] It should be noted that the horizontal continuous bending path is first scanned back and forth along the horizontal direction with a step amount dx and then progressively advanced line by line with a step amount dy.

[0034] In addition, the two-degree-of-freedom rotary table can be driven to cover the entire dual-axis angle calibration range of the fast reflector 3 via the following longitudinal continuous bending path: By (+X) max , +Y max Progress through multiple steps in increments of (0, -dy) until (+X). max , -Y max ); By (+X) max , -Y max Progress in single steps from (-dx, 0) to (+X). max - dx, -Y max ); By (+X) max - dx, -Y max Progress through multiple steps from (0, +dy) to (+X). max - dx, +Y max ); By (+X) max - dx, +Y max Progress in single steps from (-dx, 0) to (+X). max - 2dx, +Y max ); ... By analogy, the entire dual-axis angle range is gradually covered according to the continuous bending path.

[0035] It should be noted that the longitudinal continuous bending path is first scanned back and forth along the longitudinal direction with a step amount dy and then progressively advanced column by column with a step amount dx.

[0036] In this embodiment, the key parameters for the pose calibration path of the two-degree-of-freedom rotary table are set as follows: the limiting rotation angle is X. max = Y max = 10º, the step angle is dx = dy = 0.5º. At each step point of the calibration path of the two-degree-of-freedom rotary table, record the actual rotation angle of the fast reflecting mirror 3. and its angle feedback output AD code This establishes a one-to-one correspondence between the actual rotation angle and the feedback output AD code across the entire angle range, thereby providing a data foundation for subsequent nonlinear fitting or interpolation calculations.

[0037] Compared with existing technologies, this invention organically combines a high-precision two-degree-of-freedom rotary stage, an opto-autocollimator, and coarse and fine adjustment mechanisms to propose a large-angle two-dimensional fast reflector angle calibration device, system, and method based on a coaxial optical path. This solution effectively overcomes the limitation of measurement range in traditional angle calibration schemes, meets the high-precision calibration requirements of large-angle fast reflectors, and has the advantages of simple structure, convenient assembly, easy implementation, high calibration accuracy, and good repeatability. The angle calibration system is implemented by executing the steps of the angle calibration method, which constitutes a preferred embodiment of the angle calibration system. The calibration system of this invention can use host computer software, control circuits, or a combination of both to achieve coordinated control of the two-degree-of-freedom rotary stage, opto-autocollimator, and fast reflector, and process relevant drive signals, feedback signals, and measurement data during the calibration process.

[0038] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A large-angle two-dimensional fast-reflecting mirror angle calibration device, characterized in that, It includes an optoelectronic autocollimator, a fast steering mirror, an integrated adjustment base, and a two-degree-of-freedom rotary stage. The optoelectronic autocollimator is installed on the integrated adjustment base. The integrated adjustment base includes a fine adjustment base and a coarse adjustment base. The fine adjustment base is used to adjust the yaw angle and pitch angle of the optoelectronic autocollimator, and the coarse adjustment base is used to adjust the position and attitude of the optoelectronic autocollimator; The two-degree-of-freedom rotary stage includes a first rotation mechanism and a second rotation mechanism. The fast steering mirror is installed on the second rotation mechanism, and the second rotation mechanism is installed on the first rotation mechanism. The two deflection axes on the fast steering mirror are coaxially aligned with the first rotation mechanism and the second rotation mechanism. The first rotation mechanism is used to drive the fast steering mirror to rotate around the X-axis direction, and the second rotation mechanism is used to drive the fast steering mirror to rotate around the Y-axis direction; The optoelectronic autocollimator is configured with a first host computer software, and the first host computer software is used to obtain the angle deviation values (x, y) of the reflected light of the optoelectronic autocollimator in the field of view relative to the emitted optical axis in the X-axis and Y-axis directions; The two-degree-of-freedom rotary stage is configured with a second host computer software, and the second host computer software is used to control the two-degree-of-freedom rotary stage to rotate a target angle (X, Y) in the X-axis and Y-axis directions; The fast reflector has a built-in dual-axis angle feedback acquisition system, which can acquire the angle feedback signals of the fast reflector in the X and Y axes and output the corresponding feedback AD codes. .

2. A method for calibrating the angle of a large-angle two-dimensional fast reflecting mirror, characterized in that, Using the device described in claim 1, the method includes: Step S1: Perform zero calibration on the fast steering mirror and the optoelectronic autocollimator to make the optical axis of the optoelectronic autocollimator vertically pass through the center area of the fast steering mirror surface; on this basis, conduct a joint trial run of the optoelectronic autocollimator and the two-degree-of-freedom rotary stage, and complete the determination and distinction of the positive angle directions of the first host computer software and the second host computer software by recording the corresponding relationship of the readings of the two; Step S2: Control the first rotation mechanism and the second rotation mechanism of the two-degree-of-freedom rotary stage for fixed-point driving to position the two-degree-of-freedom rotary stage to the target angular position and pose (X, Y), where the target angular position and pose (X, Y) should match the compensation deflection ability of the fast steering mirror; Step S3: Drive the fast-reflecting mirror to perform a fixed-point deflection in the opposite direction to the deflection direction of the two-degree-of-freedom rotary table to achieve rotation angle compensation. When the light reflected by the autocollimator after being reflected by the fast-reflecting mirror can be re-received by the photoelectric autocollimator, and when the cursor that is close to the coordinate zero position and can be stably read is detected in the first upper-level software of the photoelectric autocollimator, record the AD code at this time. And the readings (x, y) from the first host computer software; Step S4: Based on the target angle pose (X, Y) and the readings (x, y) from the first host computer software, calculate the actual rotation angle of the fast-reflecting mirror at this moment. ; Repeat triggering steps S2 to S4 to obtain a sufficient amount of data pairs covering the entire angular range of the fast steering mirror; Step S5: Set the actual rotation angle of the fast-reflecting mirror With feedback output AD code Nonlinear fitting or interpolation calculations are performed to complete the full-range two-dimensional angle calibration of the fast reflector.

3. The method according to claim 2, characterized in that, In step S1, the zero calibration between the fast steering mirror and the optoelectronic autocollimator is completed through the following method: After the fast steering mirror and the two-degree-of-freedom rotary stage are initially returned to zero, place the laser finder supporting the optoelectronic autocollimator at the front end of the autocollimator, and adjust the spatial position and azimuth attitude of the autocollimator through the coarse adjustment base to make the laser spot emitted by the laser finder fall on the center area of the fast steering mirror surface and make the emitted light and the reflected light reach a roughly coincident state, thereby completing the coarse adjustment of the optical axis of the autocollimator; then remove the laser finder. At this time, the cursor signal can be observed in the host computer software of the autocollimator, and the cursor is moved to the zero position of the coordinate axis through the fine adjustment base, thereby completing the fine adjustment of the optical axis.

4. The method according to claim 2, characterized in that, In step S1, the determination and distinction of the positive angle directions of the first host computer software and the second host computer software are completed through the following method: Before the zero-position calibration in step S1 is completed and the formal calibration process starts, keep the fast steering mirror from deflecting, and control the two-degree-of-freedom rotating stage to run to a set of smaller-angle poses (X0, Y0). The value range of the smaller angle is specifically limited to not exceeding the field-of-view range of the first host computer software, so that the reflected light of the photoelectric autocollimator can still fall within the field-of-view acquisition range of the first host computer software, and record the readings (x0, y0) of the first host computer software in this pose; Subsequently, complete the determination and distinction of the positive direction of the angle by comparing the positive and negative sign relationships between x0 and X0, and y0 and Y0.

5. The method according to claim 4, characterized in that, In step S4, the actual rotation angle of the fast steering mirror is calculated as follows: If the positive and negative signs of x0 and X0, and y0 and Y0 are all the same, the unified formula for calculating the actual rotation angle of the fast steering mirror is specified as: If the positive and negative sign of one of x0 and X0, and y0 and Y0 is opposite, just change the plus sign to a minus sign in the corresponding formula.

6. The method according to claim 2, characterized in that, Cover the entire dual-axis angular range by following this path: Make the rotation angle of the two-degree-of-freedom rotary table from (+X) max , +Y max The transition proceeds stepwise from (±dx, 0) or (0, ±dy) to (-X). max , -Y max ).

7. The method according to claim 6, characterized in that, The path is specifically a continuous bending path in the horizontal or vertical direction; among them, the horizontal continuous bending path preferably reciprocates in the horizontal direction with a step size of dx and progresses row by row with a step size of dy; the vertical continuous bending path preferably reciprocates in the vertical direction with a step size of dy and progresses column by column with a step size of dx; the path gradually covers the entire two-axis angle range.

8. A large-angle two-dimensional fast reflector angle calibration system, characterized in that, Using the device described in claim 1, the method includes: Module M1: Perform zero-position calibration on the fast steering mirror and the photoelectric autocollimator, so that the optical axis of the photoelectric autocollimator vertically passes through the center area of the fast steering mirror surface; on this basis, conduct a joint trial run of the photoelectric autocollimator and the two-degree-of-freedom rotating stage, and complete the determination and distinction of the positive direction of the angle between the first host computer software and the second host computer software by recording the corresponding relationship of their readings; Module M2: Control the first rotating mechanism and the second rotating mechanism of the two-degree-of-freedom rotating stage to perform fixed-point driving, so that the two-degree-of-freedom rotating stage is positioned at the target angle pose (X, Y), where the target angle pose (X, Y) should match the compensation deflection ability of the fast steering mirror; Module M3: Drives the fast-reflecting mirror to deflect at a fixed point in the opposite direction to the deflection direction of the two-degree-of-freedom rotary table to achieve rotation angle compensation. When the reflected light from the autocollimator after being reflected by the fast-reflecting mirror can be re-received by the photoelectric autocollimator, and when the cursor that is close to the coordinate zero position and can be stably read is detected in the first upper-level software of the photoelectric autocollimator, the AD code at this time is recorded. And the readings (x, y) from the first host computer software; Module M4: Based on the target angle pose (X, Y) and the readings (x, y) from the first host computer software, calculate the actual rotation angle of the fast-reflecting mirror at this moment. ; Repeat triggering modules M2 to M4 to obtain a sufficient amount of data pairs covering the entire angle range of the fast steering mirror; Module M5: Actual rotation angle of the fast-reflecting mirror With feedback output AD code Nonlinear fitting or interpolation calculations are performed to complete the full-range two-dimensional angle calibration of the fast reflector.

9. The system according to claim 8, characterized in that, In module M1, the zero-position calibration between the fast steering mirror and the photoelectric autocollimator is completed through the following method: After the fast steering mirror and the two-degree-of-freedom rotating stage are initially returned to zero, place the laser finder supporting the photoelectric autocollimator at the front end of the autocollimator, and adjust the spatial position and azimuth attitude of the autocollimator through the coarse adjustment base, so that the laser beam spot emitted by the laser finder falls on the center area of the fast steering mirror surface, and make the emitted light and the reflected light reach a roughly coincident state, thereby completing the coarse adjustment of the optical axis of the autocollimator; then remove the laser finder, and at this time, the cursor signal can be observed in the host computer software of the autocollimator, and the cursor is moved to the zero position of the coordinate axis through the fine adjustment base, thereby completing the fine adjustment of the optical axis.

10. The system according to claim 8, characterized in that, In module M1, the determination and distinction of the positive direction of the angle between the first host computer software and the second host computer software are completed through the following method: Before the zero-position calibration of module M1 is completed and the formal calibration process begins, keep the fast reflector unbiased and control the two-degree-of-freedom rotary table to run to a set of small angle poses (X0, Y0). The range of values ​​for the small angles is specifically limited to not exceeding the field of view range of the first host computer software, so that the reflected light from the photoelectric autocollimator can still fall within the field of view acquisition range of the first host computer software, and record the readings (x0, y0) of the first host computer software in this pose; then, by comparing the positive and negative signs of x0 and X0, and y0 and Y0, the positive direction of the angle is determined and distinguished. In module M4, the actual rotation angle of the fast-reflecting mirror is calculated as follows: If the signs of x0 and X0, and y0 and Y0 are all the same, then the formula for calculating the actual rotation angle of the fast-reflecting mirror is uniformly defined as follows: If the signs of any term in x0 and X0, or y0 and Y0 are opposite, then the plus sign in the corresponding formula should be changed to a minus sign. Cover the entire dual-axis angular range by following this path: Make the rotation angle of the two-degree-of-freedom rotary table from (+X) max , +Y max The transition proceeds stepwise from (±dx, 0) or (0, ±dy) to (-X). max , -Y max ).

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