Optical element six-degree-of-freedom adjusting and clamping device and assembling method

Abstract

The invention provides an optical element six-degree-of-freedom adjusting and clamping device and an assembling method, and relates to the technical field of optical instruments. The device comprises a supporting base, a ball head adjusting screw, a cantilever spring mechanism and an elastic opposite ejection mechanism. The bottom of the support base is provided with a triangular layout through hole group. The center of gravity of the optical element is in the triangle. The cantilever spring mechanism and the ball head adjusting screw are combined to control Z-axis displacement and rotation around the X / Y axis, and the elastic opposite ejection mechanism and the ball head adjusting screw are combined to control X / Y-axis translation and rotation around the Z axis. All contact interfaces adopt a spherical surface-plane point contact design, and tungsten steel or phosphor bronze is selected as a material. According to the invention, six-degree-of-freedom independent precision adjustment of the optical element can be realized, the error of a clamping surface is as low as 0.068 mu rad, the structure is compact, and the adaptability is high.

Description

Technical Field

[0001] The present invention belongs to the technical field of precision optical instruments, and particularly relates to an optical element clamping device and an assembly method for ultra-high vacuum environments such as synchrotron radiation beamlines and spectrometers, and is particularly suitable for optical element fixing scenarios that require high-precision adjustment and low surface error. Background Art

[0002] With the rapid development of optical technology, high-precision optical components are increasingly widely used in fields such as synchrotron radiation light sources, spectrometers, and laser processing equipment. The clamping and adjustment accuracy of these optical components (such as mirrors, gratings, lenses, etc.) directly determines the overall performance of the optical system. Especially in synchrotron radiation beamlines, optical components need to achieve nanometer-level surface accuracy and micro-radian-level pointing stability in an ultra-high vacuum environment, which poses extremely high requirements for the design of clamping devices. On the one hand, the clamping error of optical components mainly stems from the non-ideality of the contact interface. Traditional clamping devices mostly adopt face-to-face contact methods (such as flat pressing plates or V-grooves), and this design has extremely high requirements for the flatness of machining. However, the inevitable flatness error in actual machining will cause the position drift of the clamping points, thereby introducing additional surface distortion. Literature reports (Daniele Cocco, Giovanni Sostero, Marco Zangrando, “Study of clamping-induceddeformations on SR optics by means of LTP,” Proc. SPIE 4145, Advances in X-Ray Optics, 5 January 2001) indicate that the surface error of ordinary clamping devices is generally above 1 μrad, seriously affecting the wavefront accuracy of optical components. In addition, the problem of local stress concentration at the contact surface has not been effectively solved. Especially in high-load or long-term use scenarios, stress concentration may trigger micro-cracks or surface creep of optical components. On the other hand, traditional clamping devices usually adopt rigid fixation or single-dimensional adjustment designs. For example, they directly compress through bolts or use linear guides to achieve translational adjustment. Although such devices can meet the basic fixation requirements, it is difficult to achieve independent precise adjustment of the six degrees of freedom (translation along the X / Y / Z axes and rotation around the three axes) of optical components. For example, Patent CN119017292A discloses a clamping device for special-shaped optical components and its use method, which can only achieve fine adjustment of rotation around a single axis and cannot meet the requirements of multi-dimensional joint adjustment in synchrotron radiation beamlines. At the same time, the common "three-point support" structure in the existing technology can provide certain stability, but its adjustment mechanism has strong coupling. When adjusting one dimension, it is easy to cause the deviation of other degrees of freedom, resulting in time-consuming repeated calibration and difficult accuracy guarantee. In summary, the existing clamping technologies have obvious shortcomings in structural design, material selection, and error control mechanisms, and cannot meet the increasingly stringent requirements of high-precision optical systems. In this context, the present invention aims to break through the limitations of traditional technologies through innovative designs such as a composite support structure and a spherical-plane point contact interface, and provide a new solution for the precise clamping of optical components. Summary of the Invention

[0003] The present invention aims to solve the problems of large clamping errors and limited adjustment dimensions in traditional optical element clamping devices. To achieve this purpose, in a first aspect, the present invention provides a six-degree-of-freedom adjustment clamping device for optical elements, comprising:

[0004] A support base, the bottom plane of which is provided with a first through-hole group arranged in a triangular layout;

[0005] An optical element, the center of gravity of which is located inside the triangular layout;

[0006] Ball head adjusting screws, installed in the first through-hole group and the second through-hole group on the side of the support base;

[0007] A cantilever spring mechanism, installed in the cylindrical countersunk hole on the end face of the support base, comprising a first shoulder screw, a spring and a cantilever structure, the front end of the cantilever structure being a curved surface, forming an opposing structure with the ball head adjusting screw;

[0008] An elastic opposing mechanism, installed in the threaded hole on the side of the support base and forming an opposing structure with the ball head adjusting screw, comprising a ball head, a connecting component, a pre-compressed spring and a second shoulder screw.

[0009] In one embodiment, the first through-hole group is composed of a first through-hole, a second through-hole and a third through-hole;

[0010] Wherein, the distance between the first through-hole and the second through-hole is 0.5 - 0.8 times the length of the optical element in the same direction.

[0011] In one embodiment, in the cantilever spring mechanism, the pre-compression amount and stiffness coefficient of the spring are set according to the mass of the optical element, and the total clamping force is 2 - 3 times the gravity of the optical element.

[0012] In one embodiment, the pitch of the ball head adjusting screw is 0.25 mm, the contact end with the optical element is a spherical surface structure, and the material is selected from tungsten steel or phosphor bronze.

[0013] In one embodiment, the bottom of the support base is provided with a cross-notch and a straight notch for the preliminary positioning of the optical element.

[0014] In one embodiment, in the elastic opposing mechanism, the length of the second shoulder screw is set according to the stiffness coefficient, pre-compression amount of the pre-compressed spring and the mass of the optical element.

[0015] In one embodiment, the side of the support base is provided with a trapezoidal groove for positioning the cantilever spring mechanism.

[0016] In a second aspect, the present invention provides an optical element assembly method, applicable to the above six-degree-of-freedom adjustment clamping device for optical elements, comprising the following steps:

[0017] S1. Initially position the optical element within the rectangular area formed by the cross-notch or straight-notch of the support base.

[0018] S2. Control the Z-axis displacement and rotation about the X / Y axes of the optical element by adjusting the ball-head adjusting screws in the first through-hole group.

[0019] S3. Control the X / Y-axis translation and rotation about the Z-axis of the optical element by adjusting the ball-head adjusting screws and the elastic counter-pressing mechanism in the second through-hole group.

[0020] In one embodiment, in steps S2 and S3, a laser interferometer and / or a coaxial displacement gauge is used as a feedback device, and multiple measuring heads are arranged on the surface of the optical element for real-time adjustment.

[0021] In one embodiment, the dimensions of the first through-hole group, the second through-hole group, the threaded holes, and the cross-notch of the support base are dynamically adjusted according to the length and width of the optical element.

[0022] Compared with traditional optical element clamping devices, the present invention has the following advantages:

[0023] 1. The present invention innovatively adopts a composite support structure that couples elastic deformation and rigid fine-tuning. Through the combination of the cantilever spring mechanism - ball-head adjusting screws and the elastic counter-pressing mechanism - ball-head adjusting screws, independent and precise control of the six-degree-of-freedom pose of the optical element is achieved. High-precision control can be carried out in each direction, such as Z-axis displacement, rotation about the X / Y axes, X / Y-axis translation, and rotation about the Z-axis, effectively meeting the requirements of modern optical systems for multi-dimensional precise adjustment of optical elements, especially suitable for precision optical systems such as synchrotron beamlines and spectrometers with extremely high requirements for adjustment accuracy.

[0024] 2. The present invention adopts a point-contact design. The contact interfaces between the ball-head adjusting screws, the elastic counter-pressing mechanism, and the cantilever spring mechanism and the optical element are all spherical-plane point-contact structures, fundamentally eliminating the problem of the position drift of the clamping points caused by the machining flatness error, and effectively avoiding the local stress concentration caused by non-ideal contact surfaces. Compared with the traditional face-to-face contact method, it can better maintain the surface shape accuracy of the optical element. The contact spherical surface is made of high-hardness and high-stability tungsten steel or phosphor bronze materials. Compared with some existing solutions using non-metallic materials, the problems of poor clamping accuracy and stability caused by elastic deformation and long-term creep can be effectively avoided. After actual measurement, the clamping surface shape error brought by this device is only 0.068 μrad, far superior to the clamping result of about 1 μrad of ordinary clamping devices.

[0025] 3. The present invention has good versatility and interchangeability. The ball head adjusting screw is selected as a commercially available fine pitch standard part (pitch 0.25 mm), which is convenient to obtain and has good interchangeability. At the same time, through precise calculation of the pre-compression amount and stiffness coefficient of the elastic elements, the elastic opposing mechanism and the cantilever spring mechanism ensure that the total clamping force of the system reaches 2-3 times the gravity of the optical element, effectively resisting the influence of the impact acceleration condition on the optical element and ensuring the reliability of clamping.

[0026] 4. The structural layout of the present invention is reasonable and flexible. The positions and sizes of various through holes, threaded holes, notches, etc. on the support base can be dynamically adjusted according to the size of the optical element to achieve the best support and adjustment effects and adapt to optical elements of different sizes and configurations. The cross-notch and straight notch at the bottom of the support base can provide a preliminary positioning function for the optical element, facilitating quick installation and adjustment. The elastic opposing mechanism adopts a modular design, and the parameters of its various components can be optimized according to actual needs, further improving the applicability and flexibility of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic structural diagram of the clamping device of the present invention for mounting an optical element in the correct orientation;

[0028] Figure 2 is an exploded view of the clamping device of the present invention from the perspective of the correct orientation;

[0029] Figure 3 is a schematic structural diagram of the support base of the present invention;

[0030] Figure 4 is a schematic structural diagram of the optical element of the present invention;

[0031] Figure 5 is a schematic structural diagram of the cantilever spring mechanism of the present invention;

[0032] Figure 6 is a schematic structural diagram of the end surface structure of the cantilever structure of the present invention;

[0033] Figure 7 is a schematic overall structural diagram of the elastic opposing mechanism of the present invention;

[0034] In the figure, 1 is the support base; 2 is the optical element; 2-1 is the clamping groove; 3, 5, and 7 are all ball head adjusting screws; 4 is the cantilever spring mechanism; 4-1 is the first shoulder screw; 4-2 is the spring; 4-3 is the cantilever structure; 6 and 8 are both elastic opposing mechanisms; 6-1 is the ball head; 6-2 is the connecting component; 6-3 is the pre-compressed spring; 6-4 is the second shoulder screw; 1-1-1, 1-1-2, and 1-1-3 are the first through holes; 1-3-1, 1-3-2, and 1-5 are all through holes in the second through hole group; 1-4-1, 1-4-2, and 1-6 are all threaded holes; 1-7-1, 1-7-2, 1-7-3, and 1-7-4 are all cross slots; 1-8-1 and 1-8-2 are both straight slots; 1-9-1, 1-9-2, and 1-9-3 are all trapezoidal slots. Detailed implementation mode

[0035] The following further describes the present invention in detail in conjunction with specific embodiments and the accompanying drawings of the specification, but the protection scope of the present invention is not limited to the following embodiments.

[0036] In this embodiment, a conventional optical element 2 in the synchrotron radiation field is taken as an example, and its dimensions are 200 mm in length, 40 mm in width, and 30 mm in height. The following will describe in detail the structural composition, working principle, and assembly process of the six-degree-of-freedom adjustment clamping device based on the dimensions of the optical element 2.

[0037] I. Structural composition of the six-degree-of-freedom adjustment clamping device for the optical element

[0038] 1. Support base 1:

[0039] As Figure 3 shown, the support base 1 is the basic component of the entire clamping device, and its dimensions are 238 mm in length, 76 mm in width, and 42 mm in height. It can be made of high-strength aluminum alloy or stainless steel materials to ensure the stability and rigidity of the clamping structure. The bottom plane of the support base 1 is designed with a first through hole group composed of the first through hole 1-1-1, the second through hole 1-1-2, and the third through hole 1-1-3, and these three through holes are arranged in a triangular layout. The triangular support layout designed at the bottom of the optical element 2 can provide a stable support foundation for the optical element 2 and at the same time facilitate the deflection of the optical element 2 in the X / Y axes.

[0040] Among the three through-holes in the first through-hole groups 1-1-1, 1-1-2, and 1-1-3, the aperture diameters of all of them are precisely machined to φ9.5mm to adapt to the installation of the ball head adjusting screw 3. At the same time, the distance between the first through-hole 1-1-1 and the second through-hole 1-1-2 is designed to be 0.5-0.8 times the length of the coaxial optical element. Calculated based on the length of the optical element 2 being 200mm, the value range of this distance is 100-160mm. In this embodiment, it is preferred that the distance between the first through-hole 1-1-1 and the second through-hole 1-1-2 is 130mm. Such a distance has been verified through experiments, which can ensure the balance and stability of the optical element 2 during the adjustment process while guaranteeing the adjustment flexibility, and effectively reduce the risk of the optical element 2 tilting or shaking caused by improper distance between the support points.

[0041] On the bottom plane of the support base 1, there are also four cross-notch grooves 1-7-1, 1-7-2, 1-7-3, 1-7-4 and two straight-notch grooves 1-8-1, 1-8-2. The connecting lines of the cross-notch grooves 1-7-1, 1-7-2, 1-7-3, 1-7-4 and the straight-notch grooves 1-8-1, 1-8-2 form a rectangle, and the size of this rectangle is precisely matched with the length and width of the optical element 2. Specifically, the length of this rectangle is 200mm and the width is 40mm, which is exactly the same as the bottom surface projection size of the optical element 2. Such a design enables the optical element 2 to be quickly and accurately pre-positioned. During installation, simply place the optical element 2 gently on the support base 1, and its bottom surface will fit into the rectangular area formed by the cross-notch grooves 1-7-1, 1-7-2, 1-7-3, 1-7-4 and the straight-notch grooves 1-8-1, 1-8-2, without the need for additional complex alignment operations, greatly improving the assembly efficiency. Moreover, this notch groove design also allows a certain margin for position adjustment, facilitating subsequent fine adjustment processes.

[0042] On the side of the support base 1, there are cylindrical countersunk holes 1-2-1, 1-2-2, 1-2-3, and their aperture diameters and depths are designed according to the size of the cantilever spring mechanism 4. The aperture diameters of the three cylindrical countersunk holes 1-2-1, 1-2-2, 1-2-3 are all φ10mm, and the depth is 25mm. Such dimensions can ensure that the cantilever spring mechanism 4 is stably and firmly installed on the support base 1, while ensuring that the front curved surface of the cantilever structure 4-3 and the ball head adjusting screw 3 form a precise opposing structure, providing a reliable force transmission path for the Z-axis displacement and rotation adjustment around the X / Y axis of the optical element 2.

[0043] As Figure 3As shown in the figure, on the side of the support base 1, there are also second through-hole groups 1-3-1, 1-3-2, 1-5 and threaded holes 1-4-1, 1-4-2, 1-6. The apertures of the three through-holes in the second through-hole groups 1-3-1, 1-3-2, 1-5 are all φ9.5mm, which are used to install the ball head adjustment screws 5 and 7. The three threaded holes 1-4-1, 1-4-2, 1-6 are used to install the elastic opposing mechanism 6 and 8. The layout of these hole positions has been calculated and optimized to ensure that when adjusting the optical element 2 for translation in the X / Y axes and rotation around the Z axis, the acting forces can be evenly distributed, avoiding local stress concentration, thereby improving the adjustment accuracy and the installation stability of the optical element 2.

[0044] In addition, trapezoidal grooves 1-9-1, 1-9-2, 1-9-3 are provided on the side of the support base 1, and their dimensions are adapted to the outer shape of the cantilever spring mechanism 4. The design of the trapezoidal grooves 1-9-1, 1-9-2, 1-9-3 aims to provide a precise positioning function for the cantilever spring mechanism 4, ensuring that it can be quickly and accurately positioned during the installation process, while enhancing the integrity and stability of the structure. The bottom lengths of the three trapezoidal grooves 1-9-1, 1-9-2, 1-9-3 are all 15mm, the top lengths are 10mm, and the depths are 8mm, which perfectly match the dimensions of the cantilever structure 4-3 of the cantilever spring mechanism 3.

[0045] 2. Optical element 2:

[0046] As Figure 4 shown in the figure, the optical element 2 is the core component to be clamped and adjusted by this clamping device. In this embodiment, the dimensions of the optical element 2 are 200mm in length, 40mm in width, and 30mm in height. Ensure that its center of gravity is located inside the triangular layout formed by the first through-hole group 1-1-1, 1-1-2, 1-1-3 on the bottom plane of the support base 1. Such a center of gravity layout design can ensure that the optical element 2 is evenly stressed during the adjustment process, avoiding adjustment difficulties or element shaking caused by the center of gravity offset, thereby ensuring the smoothness and accuracy of the optical element 2 during the six-degree-of-freedom adjustment process. The surface of the optical element 2 has been processed with high precision, with a surface roughness reaching Ra0.3nm and a surface shape accuracy better than λ / 10 (λ = 7nm) to meet the requirements of a high-precision optical system.

[0047] In addition, clamping grooves 2-1 are opened on the left and right sides of the optical element 2, and the clamping grooves 2-1 provide a force application platform for the curved surface structure at the front end of the cantilever structure 4-3.

[0048] 3. Ball head adjustment screws 3, 5, 7:

[0049] There are three groups of ball head adjusting screws 3, 5, and 7, all of which are commercially available fine thread standard parts with a pitch of 0.25 mm. This fine thread design has high transmission accuracy and self-locking performance, enabling precise adjustment of micro displacements and providing strong guarantee for the six-degree-of-freedom adjustment of the optical element 2. The contact end with the optical element 2 is processed into a spherical structure, and the material can be tungsten steel or phosphor bronze with high hardness and high stability. Tungsten steel has extremely high hardness and wear resistance, while phosphor bronze has good corrosion resistance and mechanical stability. It can maintain stable performance during long-term use, effectively avoiding problems such as a decrease in clamping accuracy caused by elastic deformation or long-term creep of the material.

[0050] Specifically, the ball head adjusting screws 3, 5, and 7 can be adapted to the first through-hole groups 1-1-1, 1-1-2, 1-1-3 and the second through-hole groups 1-3-1, 1-3-2, 1-5 on the support base 1, and ensure sufficient adjustment stroke.

[0051] 4. Cantilever spring mechanism 4:

[0052] As Figure 5 shown, the cantilever spring mechanism 4 is installed in the cylindrical countersunk holes 1-2-1, 1-2-2, 1-2-3 on the end face of the support base 1. Its structure includes a first shoulder screw 4-1, a spring 4-2, and a cantilever structure 4-3.

[0053] Among them, the first shoulder screw 4-1 is used to fix the spring 4-2 and the cantilever structure 4-3 on the support base 1. The spring 4-2 can be made of piano wire, which has excellent elasticity and stability. Its free length is 20 mm, the outer diameter is φ8 mm, and the wire diameter is φ1.2 mm.

[0054] The pre-compression amount of the spring 4-2 is set according to the mass of the optical element 2. Specifically, the total clamping force is controlled to be 2-3 times the gravity of the optical element 2. Calculated based on the weight of the optical element 2 being 0.56 kg (volume 200×40×30 mm 3 , the synchrotron radiation optical element 2 is made of silicon material, and the density is about 2.34 g / cm 3 ), its gravity is about 5.5 N, so the total clamping force provided by the spring 4-2 ranges from 11.0-16.5 N. Such a clamping force can not only ensure that the optical element 2 is firmly clamped during adjustment and is not affected by external vibration or impact, but also avoid surface damage or deformation of the optical element 2 caused by excessive clamping force.

[0055] The cantilever structure 4-3 can be made of alloy steel and is finely processed. Its front-end curved surface and the ball head adjusting screw 3 form a precise opposing structure. As Figure 6The radius of curvature of the shown curved surface is 4.5 mm. During the clamping process, the curved surface forms a point contact with the clamping groove 2-1 on the optical element 2, and cooperates with the ball head adjusting screw 3 below the optical element 2 to realize the fastening and adjustment of the optical element 2 in the Z-axis direction.

[0056] A through hole is provided at the rear end of the cantilever structure 4-3 for the perforated installation of the first shoulder screw 4-1. The spring 4-2 is sleeved on the outer surface of the first shoulder screw 4-1, and its two ends are respectively fixedly connected to the first shoulder screw 4-1 and the cantilever structure 4-3. Through the pre-compressive deformation of the spring 4-2, a flexible and stable clamping force is provided for the optical element 2, enabling high-precision pose control during the Z-axis displacement and rotation adjustment around the X / Y axes.

[0057] 5. Elastic opposing mechanisms 6, 8:

[0058] As Figure 2 shown, two groups of elastic opposing mechanisms 6, 8 are respectively installed in the threaded holes 1-4-1, 1-4-2, 1-6 on the side of the support base 1. The elastic opposing mechanisms 6, 8 adopt a modular design and are composed of a ball head 6-1, a connection component 6-2, a pre-compressed spring 6-3, and a second shoulder screw 6-4. The ball head 6-1 can also be made of tungsten steel or phosphor bronze, and its spherical diameter is φ5 mm, forming a point contact with the side surface of the optical element 2.

[0059] As Figure 7 shown, specifically, the connection component 6-2 can be a sleeve structure with a hollow interior and external threads. The threaded end of the second shoulder screw 6-4 penetrates through the connection component 6-2 along the axis direction of the connection component 6-2 and is threadedly engaged and fixed with the threaded hole opened at the rear end of the ball head 6-1. The pre-compressed spring 6-3 is located inside the connection component 6-2 and sleeved on the outer surface of the second shoulder screw 6-4, and its two ends are respectively fixedly connected to the bottom wall of the connection component 6-2 and the end of the second shoulder screw 6-4. Thus, a complete elastic opposing mechanism 6, 8 is assembled.

[0060] The elastic opposing mechanisms 6, 8 are installed in the threaded holes 1-4-1, 1-4-2, 1-6 of the support base 1 through the threads provided on the outer surface of the connection component 6-2.

[0061] The pre-compression spring 6-3 can be made of the same piano wire as the cantilever spring mechanism 4, with a free length of 15 mm, an outer diameter of φ6 mm, and a wire diameter of φ1.0 mm. The specifications and length of the No. 2 shoulder screw 6-4 are precisely and optimally designed according to the stiffness coefficient of the pre-compression spring 6-3, the pre-compression amount, and the mass of the optical element 2. Similarly, with the optical element weighing 0.56 kg, the total clamping force of the elastic opposed mechanism is also controlled within the range of 11.0 - 16.5 N. Such a design ensures that the elastic opposed mechanisms 6 and 8 can, while providing a stable clamping force, cooperate with the ball head adjustment screws 5 and 7 to precisely control the X-axis translation of the optical element and the rotation around the Z-axis (Yaw), and the Y-axis translation positioning, achieving high-precision adjustment of the optical element in the horizontal plane.

[0062] The positions and sizes of various through holes, threaded holes, notches, etc. on the above-mentioned support base 1 can be dynamically adjusted according to the size of the optical element 2. Taking the size of the optical element 2 in this embodiment as an example, the distance between the first through hole 1-1-1 and the second through hole 1-1-2 on the bottom plane of the support base 1 is designed to be 130 mm, and the rectangular size formed by the cross notches 1-7-1, 1-7-2, 1-7-3, 1-7-4 and the straight notches 1-8-1, 1-8-2 is 200 mm × 40 mm, which precisely matches the bottom surface size of the optical element 2. If the optical element 2 with different dimensions is replaced, for example, an optical element with a length of 150 mm, a width of 30 mm, and a height of 25 mm, only the through hole spacing and notch size on the support base 2 need to be recalculated and processed, and no large-scale modification is required for the rest of the components. This flexible structural layout design enables the present invention to quickly adapt to optical elements 2 with different sizes and configurations, meeting the diverse requirements of optical system configurations.

[0063] II. Working Principle

[0064] The working principle of the six-degree-of-freedom adjustment and clamping device for the optical element of the present invention is based on a composite support structure that couples elastic deformation and rigid fine adjustment. By reasonably arranging the clamping points and skillfully combining the functions of the cantilever spring mechanism 4, the elastic opposed mechanisms 6 and 8, and the ball head adjustment screws 3, 5, and 7, precise control of the six-degree-of-freedom pose of the optical element is achieved. Specifically:

[0065] In the vertical direction (Z-axis), the cantilever spring mechanism 4 and the ball head adjusting screw 3 act together. The cantilever spring mechanism 4 provides a downward pressure on the optical element 2 through the pre-compression deformation of the spring 4-2, while the ball head adjusting screw 3 fine-tunes the position of the optical element 2 in the Z-axis direction by screwing in or out. When the ball head adjusting screw 3 is screwed in clockwise, its spherical end pushes the bottom surface of the optical element 2, causing the optical element 2 to move in the positive Z-axis direction; conversely, when the ball head adjusting screw 3 is screwed out counterclockwise, the optical element 2 moves in the negative Z-axis direction. At the same time, since the front curved surface of the cantilever spring mechanism 4 and the ball head adjusting screw 3 form an opposing structure, when the optical element moves in the Z-axis direction, the spring 4-2 on the cantilever spring mechanism 4 will undergo corresponding elastic deformation to allow the cantilever structure 4-3 to undergo corresponding displacement to adapt to the position change of the optical element 2, thereby ensuring the smoothness and stability of the adjustment process. In addition, the elastic support function of the cantilever spring mechanism 4 can also effectively resist the influence of external impact acceleration on the Z-axis pose of the optical element, improving the stability of the system.

[0066] In terms of the adjustment of rotation (Pitch / Roll) around the X-axis and Y-axis, it is also achieved through the coordinated action of the ball head adjusting screw 3 and the cantilever spring mechanism 4. Since the center of gravity of the optical element 2 is located inside the triangular through-hole layout formed by the first through-hole groups 1-1-1, 1-1-2, and 1-1-3 at the bottom of the support base 1, when adjusting the ball head adjusting screws 3 at different positions, the optical element 2 will produce a small rotation around the corresponding axis. For example, screwing in the ball head adjusting screw 3 at the position of the third through-hole 1-1-3 will cause the optical element 2 to produce a Roll rotation around the Y-axis; when screwing in the ball head adjusting screw 3 at the position of the first through-hole 1-1-1 or the second through-hole 1-1-2 alone, the optical element 2 will produce a Pitch rotation around the X-axis. The cantilever spring mechanism 4 not only provides a clamping force in this process, but also allows the cantilever structure 4-3 to move along the axial direction of the first shoulder screw 4-1 through the elastic deformation of its spring 4-2 to adapt to the rotation of the optical element 2, ensuring the flexibility and accuracy of the rotation adjustment.

[0067] For the displacement (X-axis translation, Y-axis translation) of the optical element 2 in the horizontal plane and the adjustment of rotation (Yaw) around the Z-axis, it mainly relies on the mutual cooperation of the ball head adjusting screws 5, 7 and the elastic opposing mechanisms 6, 8. Taking the X-axis translation and Yaw adjustment as an example, the ball head adjusting screw 5 and the elastic opposing mechanism 6 form an opposing adjustment assembly. When the ball head adjusting screw 5 is screwed in clockwise, its spherical end pushes the side surface of the optical element 2, causing the optical element 2 to move in the negative X-axis direction. Conversely, when the ball head adjusting screw 5 is screwed out counterclockwise, the optical element 2 moves in the positive X-axis direction; as Figure 2As shown, there are two ball head adjusting screws 5 in total. When adjusting a single ball head adjusting screw 5, the optical element 2 can be made to rotate positively or negatively about the Z axis in Yaw. For example, when only screwing in Figure 2 the left ball head adjusting screw 5, it will push the left end of the optical element 2 to deflect clockwise. Conversely, the elastic opposing mechanism 6 will make the left end of the optical element 2 rotate counterclockwise. The elastic opposing mechanism 6 still plays a key role in balancing and clamping during this process. Due to the presence of the pre-compressed springs 6-3 inside the elastic opposing mechanisms 6 and 8, when the optical element 2 is displaced under the action of the ball head adjusting screw 5, the elastic opposing mechanisms 6 and 8 will correspondingly undergo elastic deformation, providing a balancing force in the opposite direction to the displacement direction, thus ensuring the stability and accuracy of the optical element 2 during the X-axis translation and Yaw rotation adjustment processes. Similarly, the ball head adjusting screw 7 and the elastic opposing mechanism 8 form a Y-direction opposing adjustment assembly for realizing the Y-axis translation positioning of the optical element. When screwing in or out the ball head adjusting screw 7, the optical element 2 moves correspondingly along the Y axis, and the elastic opposing mechanism 8 provides a balancing force through the elastic deformation of the pre-compressed spring 6-3 to ensure the smoothness and accuracy of the movement.

[0068] Through the collaborative action of the above components, the entire clamping device realizes the precise pose adjustment of the optical element 2 in the six-degree-of-freedom space. Each adjustment direction is independent of each other, and through a reasonable structural layout and elastic-rigid coupling design, mutual interference during the adjustment process is avoided, ensuring the adjustment accuracy and stability.

[0069] III. Assembly Process

[0070] 1. Preliminary Positioning

[0071] Gently place the optical element 2 in the rectangular area formed by the cross-shaped notches 1-7-1, 1-7-2, 1-7-3, 1-7-4 and the straight notches 1-8-1, 1-8-2 of the support base 1. Since the rectangular size formed by the cross-shaped notches 1-7-1, 1-7-2, 1-7-3, 1-7-4 and the straight notches 1-8-1, 1-8-2 precisely matches the bottom surface size of the optical element 2, the optical element 2 can be quickly and accurately placed in the predetermined position without additional complex alignment operations. At this time, the center of gravity of the optical element 2 is located inside the first through-hole group 1-1-1, 1-1-2, 1-1-3 of the triangular layout at the bottom of the support base 1, laying a good balance foundation for subsequent fine adjustment.

[0072] 2. Z-axis Displacement and Rotation Adjustment about the X / Y Axes

[0073] Using a laser interferometer and a coaxial displacement meter as feedback devices, a plurality of measuring heads are arranged on the surface of the optical element 2. The distance from the measuring head to the optical surface is determined according to the optimal working distance of the measuring head, generally 100 - 200 mm. The measuring system is used to monitor in real time the position of the optical element 2 in the Z-axis direction and the rotation angles about the X-axis and Y-axis. Slowly screw in or out the ball head adjusting screws 3 in the first through-hole groups 1-1-1, 1-1-2, and 1-1-3, and observe the data changes of the measuring system. For example, when it is necessary to increase the position of the optical element in the Z-axis direction, screw in the ball head adjusting screw 3 clockwise. The spherical end of the screw pushes the bottom surface of the optical element 2, causing the optical element to move in the positive Z-axis direction. At the same time, the front curved surface of the cantilever spring mechanism 4 and the ball head adjusting screw 3 form an opposing structure. During the movement of the optical element 2, the cantilever spring mechanism 4 undergoes elastic deformation to provide a stable clamping force for the optical element 2. According to the feedback data of the measuring system, precisely adjust the screwing-in amount of the ball head adjusting screw 3 until the optical element 2 reaches the ideal Z-axis displacement and rotation angles about the X / Y axes. During the adjustment process, due to the elastic action of the cantilever spring mechanism 4, the movement of the optical element 2 is smooth without jamming, and the adjustment accuracy can reach the micron level.

[0074] 3. Adjustment of translation in the X / Y axes and rotation about the Z axis

[0075] Similarly, using measuring devices such as a laser interferometer or a coaxial displacement meter, 2 - 3 measuring heads are arranged on the side of the optical element 2 where the clamping groove 2-1 is located, and 1 - 2 measuring heads are arranged on the front and rear end faces of the optical element 2. The measuring system is used to monitor in real time the position of the optical element 2 in the X-axis and Y-axis directions and the rotation angle about the Z axis. For the translation in the X-axis and Yaw adjustment, slowly screw in or out the ball head adjusting screws 5 in the through-holes 1-3-1 and 1-3-2 of the second through-hole group, and at the same time observe the data changes of the measuring system. For example, when it is necessary to move the optical element 2 in the negative X-axis direction, screw in the ball head adjusting screw 5 clockwise. The spherical end of the ball head adjusting screw 5 pushes the side surface of the optical element 2, causing the optical element 2 to translate in the X-axis. During this process, the elastic opposing mechanism 6 provides a balancing force in the opposite direction to the displacement direction through the elastic deformation of the internal pre-compressed spring 6-3 to ensure the smoothness and accuracy of the movement of the optical element 2. According to the feedback data of the measuring system, precisely adjust the screwing-in amount of the ball head adjusting screw 5 until the optical element 2 reaches the ideal X-axis position or Yaw angle.

[0076] For the Y-axis translation adjustment, slowly screw in or out the ball head adjustment screw 7 in the through holes 1-5 of the second through hole group, and at the same time observe the data change of the measurement system. For example, when it is necessary to move the optical element 2 in the negative Y-axis direction, screw in the ball head adjustment screw 7 clockwise. The spherical end of the ball head adjustment screw 7 pushes the front end face of the optical element 2, causing the optical element 2 to move in the negative Y-axis direction. The elastic opposing mechanism 8 provides a balancing force through the elastic deformation of the internal pre-compressed spring 6-3 to ensure the smoothness and accuracy of the movement of the optical element 2. According to the feedback data of the measurement system, precisely adjust the screwing-in amount of the ball head adjustment screw 7 until the optical element 2 reaches the ideal Y-axis position. During the entire adjustment process, the adjustment sequence and screwing-in amount of each ball head adjustment screw 3, 5, 7 need to be coordinated and adjusted according to the feedback data of the measurement system. Usually, the strategy of "coarse adjustment first and then fine adjustment" is adopted. First, quickly approach the target position through a larger screwing-in amount, and then perform fine adjustment through a small screwing-in amount until the six-degree-of-freedom pose of the optical element 2 meets the design requirements. Generally, after 3-5 iterative adjustments, the high-precision clamping and positioning of the optical element 2 can be achieved.

[0077] In summary, the six-degree-of-freedom adjustment and clamping device and assembly method for an optical element of the present invention achieve high-precision adjustment of the optical element 2 in a six-degree-of-freedom space through a carefully designed structural layout and component selection, significantly reducing the clamping surface shape error, and having good versatility, interchangeability, stability and reliability, providing an ideal solution for the design and construction of a precision optical system.

[0078] In practical applications, users can appropriately adjust and optimize the clamping device of the present invention according to the specific size and usage requirements of the optical element 2. For example, for an optical element 2 with a larger size or higher precision requirements, the size of the support base 1 can be increased, the layout of the through hole group and the notch can be adjusted accordingly, and ball head adjustment screws and elastic elements with higher precision can be selected. At the same time, an automated control and measurement system can also be equipped to realize the intelligent operation of the clamping and adjustment of the optical element 2, further improving the work efficiency and precision.

[0079] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and do not limit the protection scope of the present invention. In practical applications, those skilled in the art can appropriately adjust and optimize the structure and parameters of the present invention according to specific needs, but these adjustments and optimizations should all fall within the protection scope of the present invention.

Claims

1. A six-degree-of-freedom adjustment clamping device for optical elements, characterized in that: include: A support base (1), wherein a first through hole group (1-1-1, 1-1-2, 1-1-3) is arranged on a bottom plane thereof to form a triangular layout; An optical element (2), the center of gravity of which is located inside the triangular layout; Ball head adjustment screws (3, 5, 7) are installed in the first through hole group (1-1-1, 1-1-2, 1-1-3) and the second through hole group (1-3-1, 1-3-2, 1-5) on the side of the support base (1); A cantilever spring mechanism (4) is installed in the cylindrical countersunk holes (1-2-1, 1-2-2, 1-2-3) on the end surface of the support base (1), and comprises a No. 1 shoulder screw (4-1), a spring (4-2) and a cantilever structure (4-3); the front end of the cantilever structure (4-3) is a curved surface, and forms a top-to-top structure with the ball head adjustment screw (3); The elastic top-to-bottom mechanism (6, 8) is installed in the threaded holes (1-4-1, 1-4-2, 1-6) on the side of the support base (1) and forms a top-to-bottom structure with the ball head adjustment screws (5, 7), including a ball head (6-1), a connecting assembly (6-2), a pre-compression spring (6-3) and a No. 2 shoulder screw (6-4).

2. The six-degree-of-freedom adjustment clamping device for optical elements according to claim 1, characterized in that: The first through hole group (1-1-1, 1-1-2, 1-1-3) consists of a first through hole (1-1-1), a second through hole (1-1-2) and a third through hole (1-1-3); Wherein, the spacing between the first through hole (1-1-1) and the second through hole (1-1-2) is 0.5-0.8 times the length of the optical element (2) in the same direction.

3. The six-degree-of-freedom adjustment clamping device for optical elements according to claim 1, characterized in that: In the cantilever spring mechanism (4), the pre-compression amount and stiffness coefficient of the spring (4-2) are set according to the mass of the optical element (2), and the total clamping force is 2-3 times the gravity of the optical element (2).

4. The six-degree-of-freedom adjustment clamping device for optical elements according to claim 1, characterized in that: The pitch of the ball head adjustment screw (3, 5, 7) is 0.25 mm, the contact end with the optical element (2) is a spherical structure, and the material is selected from tungsten steel or phosphor bronze.

5. The six-degree-of-freedom adjustment clamping device for optical elements according to claim 1, characterized in that: The bottom of the support base (1) is provided with cross slots (1-7-1, 1-7-2, 1-7-3, 1-7-4) and straight slots (1-8-1, 1-8-2) for achieving preliminary positioning of the optical element (2).

6. The six-degree-of-freedom adjustment clamping device for optical elements according to claim 1, characterized in that: In the elastic top-to-top mechanism (6, 8), the length of the No. 2 shoulder screw (6-4) is set according to the stiffness coefficient of the pre-compression spring (6-3), the pre-compression amount and the mass of the optical element (2).

7. The six-degree-of-freedom adjustment clamping device for optical elements according to claim 1, characterized in that: The side of the support base (1) is provided with a trapezoidal groove (1-9-1, 1-9-2, 1-9-3) for positioning the cantilever spring mechanism (4).

8. An optical element assembly method, based on the optical element six-degree-of-freedom adjustment clamping device according to any one of claims 1 to 7, characterized in that: The following steps are involved: S1, preliminarily positioning the optical element (2) in a rectangular area formed by the cross notches (1-7-1, 1-7-2, 1-7-3, 1-7-4) and the straight notches (1-8-1, 1-8-2) of the support base (1); S2, controlling the Z-axis displacement and the rotation around the X / Y axis of the optical element (2) by adjusting the ball head adjustment screw (3) in the first through hole group (1-1-1, 1-1-2, 1-1-3); S3, by adjusting the ball head adjustment screws (5, 7) and the elastic top-to-top mechanism (6, 8) in the second through hole group (1-3-1, 1-3-2, 1-5), the X / Y axis translation and the rotation around the Z axis of the optical element (2) are controlled.

9. The optical element assembly method according to claim 8, characterized in that: In steps S2 and S3, a laser interferometer and / or a coaxial displacement meter is used as a feedback device, and a plurality of measuring heads are arranged on the surface of the optical element (2) to perform real-time adjustment.

10. The device according to claim 1, characterized in that: The sizes of the first through hole group (1-1-1, 1-1-2, 1-1-3), the second through hole group (1-3-1, 1-3-2, 1-5), the threaded holes (1-4-1, 1-4-2, 1-6) and the cross slots (1-7-1, 1-7-2, 1-7-3, 1-7-4) of the support base (1) are dynamically adjusted according to the length and width of the optical element (2).

Images