Far-field light spot measuring system and measuring method thereof

Abstract

The invention relates to the technical field of field light spot measurement, in particular to a far-field light spot measurement system and method, and the system comprises a transmitting end adjustment device and a receiving end adjustment device. The transmitting end adjusting device and the receiving end adjusting device are respectively arranged on two sides of a to-be-measured target; the first adjusting device is used for adjusting the position of the collimating lens cone and the height of the collimating lens cone so as to ensure that a laser beam emitted by the laser is aligned with a to-be-measured target after being collimated by the collimating lens cone; the receiving end adjusting device is used for receiving a laser beam at a far field; the telephoto lens is connected with the second adjusting device, and the second adjusting device is used for adjusting the position and the height of the telephoto lens to ensure that the telephoto lens receives and focuses the laser beam. The device has the advantages that four-dimensional adjustment is achieved through the displacement rotary table and the adjusting ground feet, changes of laser spots are monitored and analyzed in real time, the state of the laser device is adjusted in real time, and it is ensured that the high-speed camera collects the optimal spot image.

Description

Technical Field

[0001] The present invention relates to the technical field of far-field light spot measurement, and in particular to a far-field light spot measurement system and a measurement method thereof. Background Art

[0002] The far-field spot measurement system is a technology used to accurately measure the temporal and spatial distribution of the intensity of the laser spot under far-field conditions, which is crucial for analyzing the atmospheric transmission effect of strong lasers and evaluating the performance of laser systems. With the widespread application of laser technology in laser communications, laser radar, laser ranging and other fields, higher requirements are placed on the measurement of laser performance parameters. The far-field spot measurement system usually includes a diffuse reflection target plate, an optical lens, a CCD camera, a computer, image acquisition software and spot analysis software.

[0003] Although the existing far-field spot measurement system plays an important role in the application of laser technology, it also has some shortcomings and limitations. The first is that the system error is relatively large. Since the main optical axis of the CCD camera lens may not coincide with the normal of the diffuse reflection target plate, there is an angle, which will cause system errors. This error can be reduced by using a correction coefficient, but it still requires additional processing steps. In addition, the non-uniformity of the laser response of a single pixel of the CCD detector will affect the measurement accuracy of the spot centroid. In addition, during the spot image acquisition and processing, the system may be affected by noise, especially when there is uneven illumination or burst noise in the spot image. The traditional segmentation algorithm may not be able to accurately segment the spot. Summary of the invention

[0004] In view of this, the present invention aims to provide a far-field spot measurement system and a measurement method thereof, which ensures that the main optical axis coincides with the normal of the diffuse reflection by utilizing a first adjustment device and a second adjustment device, and is equipped with a high-performance high-speed camera for correction.

[0005] To achieve the above-mentioned purpose, the technical solution created by the present invention is implemented as follows: a far-field spot measurement system, comprising: a transmitting end adjustment device, a receiving end adjustment device and a computer; the transmitting end adjustment device and the receiving end adjustment device are respectively arranged on both sides of the target to be measured; the transmitting end adjustment device comprises a laser, a collimating lens barrel and a first adjustment device; the laser and the collimating lens barrel are arranged on the first adjustment device; the laser is connected to the collimating lens barrel through an optical fiber; the first adjustment device is configured to adjust the position of the collimating lens barrel in four degrees of freedom to ensure that the laser beam emitted by the laser is irradiated onto the target to be measured after being adjusted and expanded in diameter by the collimating lens barrel; the receiving end adjustment device comprises a telephoto lens, a second adjustment device and a high-speed camera; the telephoto lens and the high-speed camera are arranged on the second adjustment device; the telephoto lens is located at a preset position in front of the high-speed camera, and is used to receive the laser beam in the far field; the second adjustment device is configured to adjust the position of the telephoto lens in four degrees of freedom to ensure that the telephoto lens receives and focuses the laser beam to form a spot image, and the high-speed camera collects the spot image; the computer is used to calculate and analyze the spot image collected by the high-speed camera to obtain spot data.

[0006] Furthermore, the first adjustment device includes a first displacement turntable, a first connecting plate, a first connecting seat, a second connecting seat and a laser fixing seat, the first connecting plate is arranged on the first displacement turntable, the first connecting seat, the second connecting seat and the laser fixing seat are arranged on the first connecting plate, and the laser is arranged on the laser fixing seat; the first connecting seat is used to fix the front end of the collimating lens barrel, and the second connecting seat is used to fix the rear end of the collimating lens barrel; the first displacement turntable adjusts the position of the first connecting plate, thereby adjusting the position of the collimating lens barrel.

[0007] Furthermore, the first adjustment device also includes a first adjustment base plate and a first adjustment foot. The first displacement turntable and the first adjustment foot are both arranged on the first adjustment base plate. The first adjustment foot is used to adjust the height of the first adjustment base plate, thereby adjusting the height of the collimating lens barrel.

[0008] Furthermore, the first connecting seat includes a first supporting seat and a first pressure ring; the first supporting seat includes a first arc surface and a first connecting portion, the first pressure ring includes a second arc surface and a second connecting portion, when the first connecting portion is connected to the second connecting portion, the first arc surface and the second arc surface form a first accommodating cavity, and the front end of the collimating lens barrel is located in the first accommodating cavity.

[0009] Furthermore, the first connecting seat also includes a first spring and a first gasket, the first spring is located between the first connecting portion and the second connecting portion; the first gasket is arranged on the second arc surface.

[0010] Furthermore, the second adjustment device includes a second displacement turntable, a second connecting plate, a third connecting seat and a fourth connecting seat; the second connecting plate is arranged on the second displacement turntable, and the third connecting seat and the fourth connecting seat are arranged on the second connecting plate; the third connecting seat is used to fix the tail end of the telephoto lens, and the fourth connecting seat is used to fix the front end of the telephoto lens; the second displacement turntable adjusts the position of the second connecting plate, thereby adjusting the position of the telephoto lens.

[0011] Furthermore, the second adjustment device also includes a second adjustment base plate and a second adjustment foot. The second displacement turntable and the second adjustment foot are both arranged on the second adjustment base plate. The second adjustment foot is used to adjust the height of the second adjustment base plate, thereby adjusting the height of the telephoto lens.

[0012] Furthermore, the third connecting seat includes a third supporting seat and a third pressure ring; the third supporting seat includes a third arc surface and a third connecting portion, and the third pressure ring includes a fourth arc surface and a fourth connecting portion; when the third connecting portion is connected to the fourth connecting portion, the third arc surface and the fourth arc surface form a third accommodating cavity, and the tail end of the telephoto lens is located in the third accommodating cavity.

[0013] Furthermore, the first connecting seat also includes a second spring and two second gaskets, the second spring is located between the third connecting portion and the fourth connecting portion; the two second gaskets are respectively arranged on the third arc surface and the fourth arc surface.

[0014] A far-field spot measurement method is implemented using the far-field spot measurement system, comprising the following steps: S1: First, connect the laser and the collimating lens barrel to the first adjustment device respectively, and then connect the laser to the collimating lens barrel through an optical fiber to form a transmitting end adjustment device; at the same time, connect the telephoto lens and the high-speed camera to the second adjustment device respectively, and the telephoto lens is located at a preset position in front of the high-speed camera to form a receiving end adjustment device.

[0015] S2: The transmitter adjustment device and the receiver adjustment device are respectively arranged on both sides of the target to be measured.

[0016] S3: Start the laser to emit a laser beam, which is transmitted to the collimating lens barrel through the optical fiber. The collimating lens barrel adjusts the laser beam and expands its diameter before irradiating it onto the target to be measured.

[0017] S4: Adjust the pupil and optical axis of the collimator and telephoto lens respectively to ensure that the laser beam to be measured is completely received by the telephoto lens and that the far-field light spot is located at the center of the high-speed camera target surface.

[0018] S5: The computer performs calculation and analysis on the light spot image collected by the high-speed camera to obtain light spot data.

[0019] Compared with the prior art, the invention can achieve the following beneficial effects: 1) Four-dimensional adjustment is achieved by displacing the turntable and adjusting the feet, real-time monitoring and analysis of laser spot changes, and instant adjustment of the laser's working state to ensure that the high-speed camera captures the best spot image.

[0020] 2) By providing the first gasket and the first gasket made of polytetrafluoroethylene, as well as the first spring and the second spring, the collimating lens barrel and the telephoto lens can be pressed tightly without damaging the outer surfaces of the collimating lens barrel and the telephoto lens.

[0021] 3) The far-field spot measurement system has sufficient rigidity and strength to ensure that changes in the visual axis and mirror surface are within the allowable range.

[0022] 4) The present invention also has wide applicability and is compatible with various types of lasers, covering a wide range from single pulse to several hundred Hz and below medium and high energy, and has good versatility and flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The drawings constituting part of the present invention are used to provide a further understanding of the present invention. The exemplary embodiments and descriptions of the present invention are used to explain the present invention and do not constitute an improper limitation on the present invention. In the drawings: Figure 1 is a schematic structural diagram of a far-field spot measurement system provided according to an embodiment of the present invention; Figure 2 is a schematic diagram of the structure of a transmitter adjustment device provided in an embodiment of the present invention; Figure 3 is a schematic structural diagram of a first connecting socket provided according to an embodiment of the present invention; Figure 4 is a schematic diagram of the structure of a receiving end adjustment device provided according to an embodiment of the present invention; Figure 5 is a schematic structural diagram of a third connecting socket provided according to an embodiment of the present invention.

[0024] The reference numerals include: 1, transmitting end adjustment device; 11, laser; 12, collimating lens barrel; 13, first adjustment device; 131, first adjustment base plate; 132, first adjustment foot; 133, first displacement turntable; 134, first connecting plate; 135, first connecting seat; 1351, first supporting seat; 1352, first pressure ring; 1353, first spring; 1354, first gasket; 1355, first arc surface; 1356, first connecting part; 1357, second arc surface; 1358, second connecting part; 136, second connecting seat; 137, laser Device fixing seat; 2. Receiving end adjustment device; 21. Telephoto lens; 22. High-speed camera; 23. Second adjustment device; 231. Second adjustment base plate; 232. Second adjustment foot; 233. Second displacement turntable; 234. Second connecting plate; 235. Third connecting seat; 2351. Third supporting seat; 2352. Third pressure ring; 2353. Second spring; 2354. Second gasket; 2355. Third arc surface; 2356. Third connecting part; 2357. Fourth arc surface; 2358. Fourth connecting part; 236. Fourth connecting seat; 3. Target to be measured. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical solution and advantages of the invention more clear, the invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described here are only used to explain the invention and do not constitute a limitation of the invention.

[0026] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0027] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0028] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the invention can be understood according to specific circumstances.

[0029] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0030] like Figure 1 As shown, a far-field spot measurement system provided by an embodiment of the present invention includes: a transmitter adjustment device 1, a receiver adjustment device 2 and a computer; the transmitter adjustment device 1 and the receiver adjustment device 2 are respectively arranged on both sides of the target 3 to be measured. In the present invention, the plane where the first connecting plate 134 is located is defined as a first XY plane. The plane where the second connecting plate 234 is located is defined as a second XY plane.

[0031] like Figure 2 As shown, the transmitter adjustment device 1 includes a laser 11, a collimating lens barrel 12 and a first adjustment device 13; the laser 11 is connected to the collimating lens barrel 12 through an optical fiber; the collimating lens barrel 12 is connected to the first adjustment device 13; the first adjustment device 13 is used to adjust the position of the collimating lens barrel 12 on the first XY plane and the height of the collimating lens barrel 12 on the first Z axis, so as to ensure that the laser beam emitted by the laser 11 is irradiated onto the target 3 to be measured after being adjusted and expanded in diameter by the collimating lens barrel 12. The first Z axis is perpendicular to the XY plane. The laser 11, the collimating lens barrel 12 and the first adjustment device 13 together constitute the transmitter.

[0032] In this embodiment, the laser 11 is a 532 nm (±0.1 nm) solid-state laser produced by Changchun New Industries Optoelectronics Technology Co., Ltd.

[0033] The collimating lens barrel 12 receives the laser beam emitted by the laser 11, and expands the diameter of the laser beam to the required caliber according to the actual use situation. The collimating lens barrel 12 is an afocal system. The collimating lens barrel 12 is composed of two lenses, the first lens is a negative focal lens, and the second lens is a positive focal lens. The collimating lens barrel 12 composed of two lenses is smaller in size and lighter in weight. The rear surface of the first lens of the collimating lens barrel 12 is an aspherical surface, which efficiently shapes the Gaussian light into a flat top light, so that the laser beam after beam expansion presents a form of uniform intensity distribution, which not only improves the uniformity of the light spot, but also greatly shortens the length of the collimating lens barrel. In the present embodiment, the working band of the collimating lens barrel 12 is 532nm.

[0034] The first adjusting device 13 includes a first adjusting base plate 131 , a first adjusting foot 132 , a first displacement turntable 133 , a first connecting plate 134 , a first connecting seat 135 , a second connecting seat 136 and a laser fixing seat 137 .

[0035] The first adjustment base plate 131 is a rectangular plate made of aluminum alloy. The back of the first adjustment base plate 131 is lightweight. A first boss is provided on the upper surface of the first adjustment base plate 131 for mounting the first displacement turntable 133. The position of the first displacement turntable 133 is set according to the center of gravity of the transmitter adjustment device 1, and the center of gravity of the first displacement turntable 133 coincides with the center of gravity of the transmitter adjustment device 1.

[0036] The end of the first adjustment base plate 131 close to the object to be measured is defined as the front end, and the end away from the object to be measured is defined as the rear end.

[0037] A first adjustment foot 132 is installed near each of the two corners of the front end of the first adjustment base plate 131, and a first adjustment foot 132 is installed in the middle position of the rear end of the first adjustment base plate 131. The first adjustment foot 132 is used to adjust the height of the first adjustment base plate 131, and then adjust the height of the collimating lens barrel 12 in the first Z-axis direction.

[0038] The end of the collimating lens barrel 12 close to the target 3 to be measured is defined as the front end, and the end connected to the laser 11 is defined as the rear end.

[0039] The first connecting plate 134 is disposed on the first displacement turntable 133, and the first connecting seat 135, the second connecting seat 136 and the laser fixing seat 137 are disposed on the first connecting plate 134. The first connecting seat 135 is used to fix the front end of the collimating lens barrel 12, and the second connecting seat 136 is used to fix the rear end of the collimating lens barrel 12. The laser fixing seat 137 is located between the first connecting seat 135 and the second connecting seat 136, and the laser 11 is disposed on the laser fixing seat 137.

[0040] The first displacement turntable 133 is configured to realize movement in three-dimensional space with three translational degrees of freedom along the X, Y, and Z axes and one rotational degree of freedom along the Z axis.

[0041] The direction in which the first displacement turntable 133 propagates along the laser beam (i.e., the direction extending along the length of the first connection seat 135) is defined as the first X-axis. The direction in which the first displacement turntable 133 moves perpendicular to the direction in which the laser beam propagates but in the plane of the first connection seat 135 (i.e., the direction of the width of the first connection seat 135) is defined as the first Y-axis. The direction perpendicular to the plane defined by the first X-axis and the first Y-axis (i.e., the direction perpendicular to the plane where the first connection seat 135 is located) is defined as the first Z-axis.

[0042] The first displacement turntable 133 adjusts the position of the collimating lens barrel 12 in the first XY plane by adjusting the position of the first connecting plate 134 along the first X-axis and the first Y-axis and the rotation angle around the first Z-axis.

[0043] In this embodiment, the first displacement turntable 133 and the second displacement turntable 233 described below are purchased from Beijing Zhuoli Hanguang Instrument Co., Ltd., and the specific models are LSP125 or LD90, which will not be introduced in detail here.

[0044] like Figure 3 As shown, the first connection seat 135 includes a first support seat 1351, a first pressure ring 1352, a first spring 1353 and a first gasket 1354. The first support seat 1351 includes a first arc surface 1355 and a first connecting portion 1356, and the first pressure ring 1352 includes a second arc surface 1357 and a second connecting portion 1358. When the first connecting portion 1356 is connected to the second connecting portion 1358, the first arc surface 1355 and the second arc surface 1357 form a first circular accommodating cavity, and the first circular accommodating cavity is adapted to the front end of the collimating lens barrel 12, and the front end of the collimating lens barrel 12 is located in the first circular accommodating cavity.

[0045] The first gasket 1354 is arranged on the second arc surface 1357, the first spring 1353 is located between the first connection part 1356 and the second connection part 1358, and the first connection part 1356 and the second connection part 1358 are connected by bolts. The first gasket 1354 is made of polytetrafluoroethylene. By arranging the first gasket 1354 on the second arc surface 1357 and arranging the first spring 1353 between the first connection part 1356 and the second connection part 1358, the collimating lens barrel 12 can be pressed tightly without damaging the outer surface of the collimating lens barrel 12, and quick disassembly and assembly can be achieved.

[0046] The second connecting seat 136 has a similar structure to the first connecting seat 135, and includes a second supporting seat and a second pressing ring. When the second supporting seat and the second pressing ring are connected, a second circular accommodating cavity is formed. The second circular accommodating cavity is adapted to the rear end of the collimating lens barrel 12, and the rear end of the collimating lens barrel 12 is located in the second circular accommodating cavity.

[0047] In this embodiment, the first adjustment device 13 further includes a dust cover, which is disposed on the first connecting plate 134. The dust cover is provided with a circular hole on one side close to the front end of the collimating lens barrel 12 for the laser beam to pass through.

[0048] The direction of the second displacement turntable 233 along the propagation direction of the laser beam (i.e., the direction extending along the length of the third connection seat 235) is defined as the second X-axis. The direction of the second displacement turntable 233 moving in the plane of the third connection seat 235 perpendicular to the propagation direction of the laser beam (i.e., the direction of the width of the third connection seat 235) is defined as the second Y-axis. The direction perpendicular to the plane determined by the second X-axis and the second Y-axis (i.e., the direction perpendicular to the plane where the third connection seat 235 is located) is defined as the second Z-axis.

[0049] like Figure 4 As shown, the receiving end adjustment device 2 includes a telephoto lens 21, a high-speed camera 22 and a second adjustment device 23; the telephoto lens 21 is located at a preset position directly in front of the high-speed camera 22, and is used to receive the laser beam in the far field; the telephoto lens 21 is connected to the second adjustment device 23, and the second adjustment device 23 is used to adjust the position of the telephoto lens 21 in the second XY plane and the height of the telephoto lens 21 in the second Z-axis direction to ensure that the telephoto lens 21 receives and focuses the laser beam; the high-speed camera 22 collects the spot image formed by the laser beam irradiated on the target 3 to be measured. The telephoto lens 21, the high-speed camera 22 and the second adjustment device 23 together constitute the receiving end.

[0050] The working band of the telephoto lens 21 is 532nm, and it includes a lens group consisting of two lenses, a reflector, a secondary mirror, and a primary mirror.

[0051] The high-speed camera 22 is connected to the second connecting plate 234 through an adjustment base, and the adjustment base can achieve displacement in three directions. The present invention does not introduce the structure of the adjustment base in detail, as long as the displacement adjustment of the high-speed camera 22 in three directions can be achieved. The high-speed camera is an outsourced part, model MEMRECAM ACS-1 M40.

[0052] The second adjusting device 23 includes a second adjusting base plate 231 , a second adjusting foot 232 , a second displacement turntable 233 , a second connecting plate 234 , a third connecting seat 235 and a fourth connecting seat 236 .

[0053] The second adjustment base plate 231 is a rectangular plate made of aluminum alloy. The back of the second adjustment base plate 231 adopts a lightweight design. A second boss is provided on the upper surface of the second adjustment base plate 231 for mounting the second displacement turntable 233. The position of the second displacement turntable 233 is set according to the center of gravity of the transmitter adjustment device 1, and the center of gravity of the second displacement turntable 233 coincides with the center of gravity of the receiver adjustment device 2. A second adjustment foot 232 is installed near each of the two corners of the second adjustment base plate 231 on the side close to the target 3 to be measured, and a second adjustment foot 232 is installed in the middle position of the second adjustment base plate 231 away from the target 3 to be measured. The second adjustment foot 232 is used to adjust the height of the second adjustment base plate 231, and then adjust the height of the telephoto lens 21 in the second Z-axis direction.

[0054] In this embodiment, the end of the telephoto lens 21 close to the high-speed camera 22 is defined as the rear end, and the end of the telephoto lens 21 away from the high-speed camera 22 is defined as the front end.

[0055] The second connecting plate 234 is disposed on the second displacement turntable 233, and the third connecting seat 235 and the fourth connecting seat 236 are disposed on the second connecting plate 234. The third connecting seat 235 is used to fix the rear end of the telephoto lens 21, and the fourth connecting seat 236 is used to fix the front end of the telephoto lens 21. The second displacement turntable 233 adjusts the position of the second connecting plate 234 along the second X-axis direction and the second Y-axis direction and the rotation angle around the second Z-axis, thereby adjusting the position of the telephoto lens 21 in the second XY plane.

[0056] like Figure 5 As shown, the third connecting seat 235 includes a third supporting seat 2351 , a third pressing ring 2352 , a second spring 2353 and two second gaskets 2354 .

[0057] The third support seat 2351 includes a third arc surface 2355 and a third connecting portion 2356, and the third pressing ring 2352 includes a fourth arc surface 2357 and a fourth connecting portion 2358. When the third connecting portion 2356 is connected to the fourth connecting portion 2358, the third arc surface 2355 and the fourth arc surface 2357 form a third circular accommodating cavity, and the third circular accommodating cavity is adapted to the rear end of the telephoto lens 21, and the rear end of the telephoto lens 21 is located in the third circular accommodating cavity.

[0058] The two second gaskets 2354 are respectively arranged on the third arc surface 2355 and the fourth arc surface 2357, the second spring 2353 is located between the third connection part 2356 and the fourth connection part 2358, and the third connection part 2356 and the fourth connection part 2358 are connected by bolts. The two second gaskets 2354 are made of polytetrafluoroethylene. By arranging the second gaskets 2354 on the third arc surface 2355 and the fourth arc surface 2357, and arranging the second spring 2353 between the third connection part 2356 and the fourth connection part 2358, the telephoto lens 21 can be pressed tightly without damaging the outer surface of the telephoto lens 21, and quick disassembly and assembly can be achieved.

[0059] The fourth connecting seat 236 has a similar structure to the third connecting seat 235, and includes a fourth supporting seat and a fourth pressing ring. When the fourth supporting seat and the fourth pressing ring are connected, a fourth circular accommodating cavity is formed. The fourth circular accommodating cavity is adapted to the front end of the telephoto lens 21, and the front end of the telephoto lens 21 is located in the fourth circular accommodating cavity.

[0060] At the transmitting end, the laser 11 emits a laser beam, which is transmitted to the collimating lens barrel 12 through an optical fiber. The collimating lens barrel 12 adjusts the laser beam and expands the diameter before irradiating it onto the target 3 to be measured. At the receiving end, the telephoto lens 21 receives the laser beam from the target 3 to be measured, and focuses it on the target surface of the high-speed camera 22 to form a light spot. The high-speed camera 22 collects and records the light spot image information. The computer calculates and analyzes the light spot image collected by the high-speed camera 22 to obtain the light spot data.

[0061] To ensure that the far-field spot measurement system has sufficient rigidity and strength; at the same time, it has good dimensional stability under harsh temperature conditions to ensure that the changes in the visual axis and mirror surface are within the allowable range. To this end, a comprehensive engineering analysis of its optical and mechanical structure was carried out to analyze the rigidity feasibility of the far-field spot measurement system, including mechanical properties such as static rigidity and dynamic rigidity, as well as the ability to resist mechanical vibration interference under emission and space working conditions. The engineering analysis was modeled using NX and solved using NX / Nastran. The analysis results showed that the far-field spot measurement system structure is stable and reliable.

[0062] A far-field spot measurement method is implemented using the far-field spot measurement system, comprising the following steps: S1: First, connect the laser 11 and the collimating lens barrel 12 to the first adjusting device 13 respectively, and then connect the laser 11 to the collimating lens barrel 12 through an optical fiber to form a transmitting end adjusting device 1; at the same time, connect the telephoto lens 21 and the high-speed camera 22 to the second adjusting device 23 respectively, and the telephoto lens 21 is located at a preset position directly in front of the high-speed camera 22 to form a receiving end adjusting device 2.

[0063] S2: The transmitter adjustment device 1 and the receiver adjustment device 2 are respectively arranged on both sides of the target 3 to be measured.

[0064] S3: Start the laser 11, the laser 11 emits a laser beam, and the laser beam is transmitted to the collimating lens barrel 12 through the optical fiber. The collimating lens barrel 12 adjusts the laser beam and expands the diameter, and then irradiates the laser beam onto the target 3 to be measured.

[0065] S4: respectively adjusting the pupil and the optical axis of the collimating lens barrel 12 and the telephoto lens 21 to ensure that the laser beam to be measured is completely received by the telephoto lens 21 and that the far-field light spot is located at the center of the target surface of the high-speed camera 22 .

[0066] The pupil and the optical axis of the collimating lens 12 and the telephoto lens 21 are adjusted respectively by the first displacement turntable 133 and the second displacement turntable 233 .

[0067] S5: The computer performs calculation and analysis on the light spot image collected by the high-speed camera 22 to obtain light spot data.

[0068] The above specific implementations do not constitute a limitation on the protection scope of the present invention. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A far-field spot measurement system, characterized in that: include: A transmitter adjustment device, a receiver adjustment device and a computer; the transmitter adjustment device and the receiver adjustment device are respectively arranged on both sides of the target to be measured; The transmitting end adjustment device comprises a laser, a collimating lens barrel and a first adjustment device; the laser and the collimating lens barrel are arranged on the first adjustment device; the laser is connected to the collimating lens barrel through an optical fiber; the first adjustment device is configured to adjust the position of the collimating lens barrel in four degrees of freedom to ensure that the laser beam emitted by the laser is irradiated onto the target to be measured after being adjusted and expanded in diameter by the collimating lens barrel; The receiving end adjustment device includes a telephoto lens, a second adjustment device and a high-speed camera; the telephoto lens and the high-speed camera are arranged on the second adjustment device; The telephoto lens is located at a preset position in front of the high-speed camera and is used to receive the laser beam in the far field; The second adjustment device is configured to adjust the position of the telephoto lens in four degrees of freedom to ensure that the telephoto lens receives and focuses the laser beam to form a light spot image, and the high-speed camera collects the light spot image; A computer is used to perform calculation and analysis on the light spot image collected by the high-speed camera to obtain light spot data.

2. The far-field spot measurement system according to claim 1, characterized in that: The first adjustment device includes a first displacement turntable, a first connecting plate, a first connecting seat, a second connecting seat and a laser fixing seat, the first connecting plate is arranged on the first displacement turntable, the first connecting seat, the second connecting seat and the laser fixing seat are arranged on the first connecting plate, and the laser is arranged on the laser fixing seat; the first connecting seat is used to fix the front end of the collimating lens barrel, and the second connecting seat is used to fix the rear end of the collimating lens barrel; the first displacement turntable adjusts the position of the first connecting plate, thereby adjusting the position of the collimating lens barrel.

3. The far-field spot measurement system according to claim 2, characterized in that: The first adjustment device also includes a first adjustment base plate and a first adjustment foot. The first displacement turntable and the first adjustment foot are both arranged on the first adjustment base plate. The first adjustment foot is used to adjust the height of the first adjustment base plate, thereby adjusting the height of the collimating lens barrel.

4. The far-field spot measurement system according to claim 2, characterized in that: The first connecting seat includes a first supporting seat and a first pressing ring; the first supporting seat includes a first arc surface and a first connecting portion, the first pressing ring includes a second arc surface and a second connecting portion, when the first connecting portion is connected to the second connecting portion, the first arc surface and the second arc surface form a first accommodating cavity, and the front end of the collimating lens barrel is located in the first accommodating cavity.

5. The far-field spot measurement system according to claim 4, characterized in that: The first connecting seat also includes a first spring and a first gasket, wherein the first spring is located between the first connecting portion and the second connecting portion; and the first gasket is arranged on the second arc surface.

6. The far-field spot measurement system according to claim 1, characterized in that: The second adjustment device includes a second displacement turntable, a second connecting plate, a third connecting seat and a fourth connecting seat; the second connecting plate is arranged on the second displacement turntable, and the third connecting seat and the fourth connecting seat are arranged on the second connecting plate; the third connecting seat is used to fix the rear end of the telephoto lens, and the fourth connecting seat is used to fix the front end of the telephoto lens; the second displacement turntable adjusts the position of the second connecting plate, thereby adjusting the position of the telephoto lens.

7. The far-field spot measurement system according to claim 6, characterized in that: The second adjustment device also includes a second adjustment base plate and a second adjustment foot. The second displacement turntable and the second adjustment foot are both arranged on the second adjustment base plate. The second adjustment foot is used to adjust the height of the second adjustment base plate, thereby adjusting the height of the telephoto lens.

8. The far-field spot measurement system according to claim 6, characterized in that: The third connecting seat includes a third supporting seat and a third pressing ring; the third supporting seat includes a third arc surface and a third connecting portion, and the third pressing ring includes a fourth arc surface and a fourth connecting portion; when the third connecting portion is connected to the fourth connecting portion, the third arc surface and the fourth arc surface form a third accommodating cavity, and the tail end of the telephoto lens is located in the third accommodating cavity.

9. The far-field spot measurement system according to claim 8, characterized in that: The first connecting seat also includes a second spring and two second washers, wherein the second spring is located between the third connecting portion and the fourth connecting portion; and the two second washers are respectively arranged on the third arc surface and the fourth arc surface.

10. A far-field spot measurement method, implemented by using the far-field spot measurement system according to any one of claims 1 to 9, characterized in that: The steps include: S1: First, the laser and the collimating lens barrel are connected to the first adjustment device respectively, and then the laser is connected to the collimating lens barrel through an optical fiber to form the transmitting end adjustment device; at the same time, the telephoto lens and the high-speed camera are connected to the second adjustment device respectively, and the telephoto lens is located at a preset position in front of the high-speed camera to form the receiving end adjustment device; S2: placing the transmitter adjustment device and the receiver adjustment device on both sides of the target to be measured respectively; S3: starting the laser, the laser emits a laser beam, the laser beam is transmitted to the collimating lens barrel through the optical fiber, the collimating lens barrel adjusts the laser beam and expands the diameter, and then irradiates the laser beam onto the target to be measured; S4: adjusting the pupil and the optical axis of the collimating lens barrel and the telephoto lens respectively to ensure that the laser beam to be measured is completely received by the telephoto lens, so that the far-field light spot is located at the center of the target surface of the high-speed camera; S5: The computer performs calculation and analysis on the light spot image collected by the high-speed camera to obtain light spot data.

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