A large stroke high bandwidth fast mirror device

Abstract

This invention relates to the field of high-precision opto-electro-mechanical servo tracking technology, and discloses a fast-reflecting mirror device with a large stroke and high bandwidth, enabling rapid pointing and scanning of a light beam over a wide range. The device specifically includes a fast-reflecting mirror base, a displacement sensor, a reflector, a flexible amplification mechanism, and electromagnetic actuators. Three evenly distributed sets of electromagnetic actuators drive a mover that moves the flexible amplification mechanism, thereby driving the reflector to produce yaw motion around its axis and along its axis, as well as yaw motion and displacement motion. This invention, through a multi-functional integrated design of the reflector and flexible amplification mechanism, reduces the use of a mirror holder, lowers the rotational inertia of the fast-reflecting mirror's moving parts, and simplifies the assembly process, thereby improving the natural frequency and assembly accuracy of the fast-reflecting mirror device and achieving a balance between the large stroke and high bandwidth performance of the fast-reflecting mirror.

Description

Technical Field

[0001] This invention relates to the field of high-precision opto-electro-mechanical servo tracking technology, specifically to a fast reflector device with a large stroke and high bandwidth. Background Technology

[0002] A fast-steering mirror is a precision opto-mechanical device that accurately controls the direction of a light beam. It is widely used in various scientific applications and can be further divided into pointing and scanning applications. Typical pointing applications include capturing light signals and tracking targets, line-of-sight stabilization in optical systems (such as free-space laser communication), and pointing lasers or light beams. Scanning applications are very broad, ranging from materials processing to confocal microscopy and scanning optical lithography.

[0003] In practical applications, fast reflectors often require both a large stroke and a high bandwidth to meet the demands of rapid tracking at low frequencies and large angles, as well as compensation at high frequencies and small angles. Common fast reflectors are based on piezoelectric actuators (PEA) or voice coil motor actuators. Voice coil motor actuators are primarily used in low-stiffness systems with large strokes but relatively limited bandwidth, while piezoelectric actuators are generally used in high-stiffness systems with high bandwidth but relatively limited stroke. Generally, large stroke and high bandwidth are contradictory and difficult to achieve simultaneously. To balance these two aspects, fast reflector devices based on magnetoresistive actuators are a promising alternative. Compared to voice coil motor actuators, magnetoresistive actuators have a higher force density, and compared to piezoelectric actuators, they can achieve a larger stroke. However, this type of fast-reflecting mirror also faces great challenges in its implementation, such as nonlinear problems of force and current, magnetic resistance and gap, hysteresis and leakage magnetic phenomena of magnetic materials, and negative stiffness problems. These challenges make it difficult to accurately model and control the system, and innovation is urgently needed in terms of configuration design and flexible structure. Summary of the Invention

[0004] (a) Purpose of the invention

[0005] The purpose of this invention is to propose a novel large-stroke, high-bandwidth, fast-reflecting mirror device, which has a large light-transmitting aperture of 50mm radius. It features a mechanical deflection angle and a first-order natural frequency above 500Hz. This meets the requirements for large-aperture beam scanning applications with wide angles and broad frequencies.

[0006] (II) Technical Solution

[0007] To achieve the above objectives, the present invention provides the following technical solution: a fast-reflecting mirror device with a large stroke and high bandwidth, comprising a fast-reflecting mirror base, displacement sensors, a reflector, a flexible amplification mechanism, and an electromagnetic actuator; the electromagnetic actuator consists of a permanent magnet, a resin layer, an electromagnetic actuator mover, an iron core, a coil frame, and a coil; the reflector is securely connected to three sets of flexible amplification mechanisms, and each set of flexible amplification mechanisms is securely connected to the electromagnetic actuator mover at its rear; the three sets of electromagnetic actuators are evenly distributed along the circumference and fixed to the fast-reflecting mirror base; a driving voltage is applied to the three sets of coils respectively, causing a magnetic flux difference between the upper and lower working air gaps of the electromagnetic actuator mover, driving the electromagnetic actuator mover to drive the flexible amplification mechanism to produce rotational deformation motion, thereby driving the reflector to produce yaw motion and displacement motion; the displacement sensor consists of three identical eddy current sensors, evenly distributed along the circumference and fixed to the fast-reflecting mirror base by set screws; the height of the three sets of displacement sensors is along the circumference... The probe is adjustable and positioned at the same distance from the back of the reflector. It is used to detect the linear displacement changes of three points on the back of the reflector, and the results are calculated using coordinate transformation to obtain the reflector's orbital position. shaft and The yaw angle of the axis and along Linear displacement in the direction.

[0008] Preferably, the reflector is integrally machined from metal material, with a mirror structure on the upper surface and a lower surface that is securely connected to the flexible magnification mechanism.

[0009] Preferably, the flexible amplification mechanism is a multifunctional integrated unit. Its front end is connected to the reflector via a positioning pin, its rear end is fastened to the electromagnetic actuator mover via a tenon joint, and its bottom two sides are fixed to the fast reflector base via screws. This design enables motion transmission and stroke amplification, along with... shaft and Flexible deformation of the axis degree of freedom and parasitic circular motion at the end of the compensating flexible amplification mechanism.

[0010] Preferably, the permanent magnets are symmetrically distributed above and below the electromagnetic actuator mover, with their upper or lower ends fastened to the iron core and their sides fastened to the resin layer; the resin layer is used to fix the permanent magnets and guide the magnetic flux path; the coil frame is used to support and fix the coil and also serves as insulation.

[0011] Preferably, the fast reflector base is made of aluminum alloy and has mounting slots for an electromagnetic actuator, a flexible amplification mechanism, a displacement sensor, and mounting holes for fixing the base. The displacement sensor can be replaced with a capacitive sensor or a photoelectric displacement sensor.

[0012] Preferably, the reflector is made of microcrystalline aluminum, titanium, beryllium, or structural steel, and has a positioning hole and a reinforcing rib structure on the back. The positioning hole is used for positioning and installation with the flexible magnification mechanism through the pin hole, and the reinforcing rib structure is used to ensure the rigidity of the mirror surface while achieving lightweight design.

[0013] Preferably, the flexible amplification mechanism is made of a metal material such as aluminum alloy or titanium alloy, which has both low elastic modulus and high yield strength, and includes a flexible structure, an elliptical omnidirectional notch flexible hinge structure, and an arc-shaped unidirectional notch flexible hinge structure; the two ends of the rod of the flexible structure are suspended from the column through a two-cylinder structure, and the column is fixed to the fast reflector base by screws; the elliptical omnidirectional notch flexible hinge structure is located at the end of the flexible amplification mechanism, and in the direction of rotation... shaft and The axis has the same bending stiffness in both degrees of freedom; the arc-shaped unidirectional notch flexible hinge structure is located at the "right angle" at the end of the "L"-shaped rod, and is used to compensate for the parasitic motion at the end of the flexible mechanism.

[0014] Preferably, the electromagnetic actuator is positioned by the iron core and the boss in the mounting groove of the fast reflector base, and is fixedly connected by epoxy resin adhesive.

[0015] Preferably, the three sets of electromagnetic actuators are evenly distributed on a circumference and spaced 120° apart. Their points of action are distributed on a circumference with a radius of 10mm, arranged clockwise. The points of action of the electromagnetic actuators are located at... On the shaft; groups of displacement sensors are evenly distributed on a circle concentric with the electromagnetic actuator, arranged at intervals from the electromagnetic actuator in a clockwise direction, wherein the displacement sensors are located on... On the shaft, the radius of the sensor distribution circle is the same as the radius of the electromagnetic actuator's point of action, both being 10mm.

[0016] Preferably, the large-stroke, high-bandwidth, fast-reflecting mirror device further includes a magnetic shielding assembly. The magnetic shielding assembly is a ring structure made of permalloy material with high magnetic permeability, sleeved on the outside of the electromagnetic actuator, and fixed to the fast-reflecting mirror base by bolts. A 2-3mm gap is reserved between the inner wall of the magnetic shielding assembly and the outer wall of the electromagnetic actuator, and the gap is filled with flexible insulating material. The height of the magnetic shielding assembly is the same as the height of the electromagnetic actuator, which can reduce the leakage magnetic field strength generated by the electromagnetic actuator to below the allowable value of the external environment, and avoid magnetic interference to the precision electronic components around the device.

[0017] In summary, this invention provides a long-stroke, high-bandwidth, fast-reflecting mirror device that can achieve orbital... axis, Axial runout and along The mirror exhibits three degrees of freedom: yaw and tilt. Electromagnetic actuators HRA1, HRA2, and HRA3, along with displacement sensors ECS1, ECS2, and ECS3, are evenly distributed on the concentric circumference of the base. By applying different voltages to the three sets of electromagnetic actuators, the mover is activated, and the force and motion are transmitted to the three points of application on the mirror surface via a flexible amplification mechanism, thereby driving the mirror to yaw and tilt. Simultaneously, the three sets of displacement sensors measure the displacement changes at three measurement points on the back of the mirror, and calculate the actual spatial motion of the mirror based on geometric relationships. Finally, a high-speed data acquisition and control system is integrated to achieve closed-loop control of the fast-reflecting mirror, meeting the requirements of scanning applications.

[0018] The fast reflector device provided by this invention differs significantly from other existing fast reflectors in terms of actuator configuration, reflector structure, and flexible amplification mechanism.

[0019] (1) A permanent magnet bias reluctance actuator combined with a flexible amplification mechanism is used to drive the reflector. The bias flux is provided by the permanent magnet, which reduces the current amplitude and heat generation of the control coil, improves the overall force density and movement speed of the actuator under volume constraints, and ensures the high bandwidth operation of the reflector. With the help of the flexible amplification mechanism, the large-volume reluctance actuator is externally mounted, which not only increases the movement stroke of the reflector, but also reserves space for the design of large-aperture reflectors and the improvement of the beam incident range.

[0020] (2) The reflector is an integrated structure, machined from a single piece using high-performance metal materials. This design integrates the traditional reflector assembly, which consists of a reflector surface, a mirror holder, and a mirror connection structure, into a single reflector part. The integrated design reduces the rotational inertia of the reflector assembly, which helps to increase the natural frequency of the fast reflector system. In addition, the integrated structure simplifies the assembly process and reduces assembly errors, thereby maximizing the consistency between the model and the actual object in terms of accuracy.

[0021] (3) The flexible amplification mechanism is a multifunctional integrated unit. Its first function is to realize motion transmission and stroke amplification; its second function is to provide a path along the end of the flexible amplification mechanism and the back of the reflector. shaft and The system possesses flexible deformation capabilities across its axial degrees of freedom; its third function is to compensate for the parasitic circular motion at the end of the flexible amplification mechanism. This multifunctional integrated structure design reduces the use of redundant parts, achieving weight reduction and consequently lowering the equivalent moment of inertia to increase the system's natural frequency. Furthermore, the integrated design reduces complex assembly processes and assembly-related errors, thereby improving model accuracy and ensuring control performance.

[0022] (III) Beneficial Effects

[0023] Compared with the prior art, the present invention provides a fast reflecting mirror device with a long stroke and high bandwidth, which has the following beneficial effects:

[0024] 1. This long-stroke, high-bandwidth fast reflector device utilizes a permanent magnet biased reluctance actuator in conjunction with a flexible amplification mechanism to effectively improve the force density and movement speed of the actuator under volume constraints, ensuring the high-bandwidth operation of the fast reflector. At the same time, it realizes the external placement of the actuator, which helps to increase the movement stroke of the fast reflector, design a large-aperture reflector, and expand the beam incident range.

[0025] 2. This long-stroke, high-bandwidth fast reflector device utilizes an integrated structure with a mirror made of metal material, which effectively reduces the structural complexity of the mirror assembly and the mass and rotational inertia of the moving components, thus significantly improving the natural frequency of the fast reflector.

[0026] 3. This long-stroke, high-bandwidth fast-reflecting mirror device utilizes a multi-functional, composite, flexible amplification mechanism integrated unit to combine motion transmission and stroke amplification functions along the path... shaft and The design integrates the flexible deformation capability of the axis degree of freedom with the parasitic circular motion at the end of the flexible amplification mechanism, reducing complex assembly processes, minimizing assembly errors, and ensuring the motion accuracy of the flexible amplification mechanism. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the long-stroke, high-bandwidth, fast-reflecting mirror provided by the present invention;

[0028] Figure 2 This is a schematic diagram of the piezoelectric drive and displacement sensor configuration scheme for a large-stroke, high-bandwidth, fast-reflecting mirror provided by the present invention;

[0029] Figure 3 This is a cross-sectional schematic diagram of the long-stroke, high-bandwidth, fast-reflecting mirror provided by the present invention;

[0030] Figure 4 This is a schematic diagram of the flexible hinge used in the long-stroke, high-bandwidth, fast-reflecting mirror provided by the present invention;

[0031] Figure 5 This is a front view structural diagram of the magnetic shielding component of the large-stroke, high-bandwidth, fast-reflecting mirror device provided by the present invention.

[0032] In the figure: 101, fast reflector base; 102, displacement sensor; 103, reflector; 104, flexible amplification mechanism; 105, permanent magnet; 106, resin layer; 107, electromagnetic actuator mover; 108, iron core; 109, coil frame; 110, coil; 111, magnetic shielding assembly. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be clearly understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. This invention can be implemented in various forms and should not be limited to the embodiments set forth herein. The terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also mean including the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more.

[0034] See appendix Figure 1 - Appendix Figure 5 The image shows a long-stroke, high-bandwidth, fast-reflecting mirror device proposed in this invention. Wherein:

[0035] Appendix Figure 1 This is a schematic diagram of the overall appearance of the fast reflector;

[0036] Appendix Figure 2 The provided implementation example includes the arrangement scheme of the electromagnetic actuators (HRA1, HRA2, HRA3) and displacement sensors (ECS1, ECS2, ECS3), as well as the coordinate system definition of the fast reflector. axis, The axis, the origin O, and the perpendicular line passing through point O planar In the diagram, HRA1, HRA2, and HRA3 represent the points of action of the electromagnetic actuator on the back of the reflector via the flexible amplification mechanism. The axis is any diameter along the mirror surface. The axis is with The axis is perpendicular to the axis that passes through the center point of the mirror circle.

[0037] The arrangement of actuators and sensors is as follows: Figure 2 As shown, three sets of electromagnetic actuators are evenly distributed on a circumference and spaced apart from each other. The degree, and its points of action HRA1, HRA2, and HRA3 are distributed in a radius of The actuators are arranged in a clockwise direction on the circumference of a circle, with the point of action of actuator number 1 being... On the axis. Three sets of sensors are also evenly distributed on a circle concentric with the electromagnetic actuator, spaced apart from the actuator, arranged in a clockwise direction. Sensor number 2, ECS2, is located on... On the axis. For ease of calculation, the radius of the sensor distribution circle is taken to be the same as the circumference of the electromagnetic actuator's point of action, i.e. .

[0038] Under the above arrangement, the reflector 103 is surrounded , Yaw angle in the direction of freedom and along The axial displacement can be measured by three eddy current sensors. The transformation matrix is ​​obtained through coordinate transformation. The formula is as follows:

[0039]

[0040] in: Each is a mirror edge axis, Shaft yaw angle (unit: ); For the mirror edge Displacement of the shaft (unit: mm); is the radius of the circle where the sensor is located (unit: mm); k=1000 is the unit conversion factor.

[0041] Appendix Figure 3 The provided implementation example shows a cross-sectional schematic diagram of the fast reflector device, illustrating the composition of the fast reflector and the assembly relationship between the various components.

[0042] The components of the fast reflector system include: fast reflector base 101, displacement sensor 102, reflector 103, flexible amplification mechanism 104, permanent magnet 105, resin layer 106, electromagnetic actuator mover 107, iron core 108, coil frame 109, and coil 110.

[0043] Fast reflector base 101: The fast reflector base is a component that provides stable support and precise reference for other components. It is made of aluminum alloy, but other materials with suitable rigidity can be used instead. The base is designed with mounting slots for electromagnetic actuators, flexible amplification mechanisms, displacement sensors, and mounting holes for fixing the base.

[0044] Displacement sensor 102: In this embodiment, three identical eddy current sensors are selected as the sensing and measurement units of the fast reflector. They are evenly distributed on a circumference at 120° intervals and fixed to the fast reflector base 101 by set screws on the side of the base mounting slot. The measuring head is adjusted to maintain a consistent distance from the back of the reflector. The three sets of eddy current sensors measure the displacement of corresponding measurement points on the back of the reflector, and the displacement of the reflector around the back is calculated using the aforementioned transformation matrix. shaft and The yaw angle of the axis and along Linear displacement in the direction of motion. Other types of displacement sensors, such as capacitive sensors and photoelectric displacement sensors, can be selected according to different needs.

[0045] Reflector 103: The reflector is the core component of the fast reflector device, used to change the propagation direction of the light beam. In this embodiment, the reflector is designed with a light-transmitting aperture of 50mm and is made of microcrystalline aluminum. A positioning hole is designed on the back of the reflector, allowing it to be positioned and installed with the flexible amplification mechanism via pin holes, and then fixed with epoxy adhesive. A reinforcing rib structure is designed on the back of the reflector, which reduces the reflector's rotational inertia to achieve weight reduction while ensuring a certain rigidity of the mirror surface. The material of the reflector can be changed as needed, such as titanium, beryllium, and structural steel.

[0046] Flexible amplification mechanism 104: The flexible amplification mechanism is the core component of the fast reflector device, used to transmit the motion and force of the electromagnetic actuator. In this embodiment, the flexible amplification mechanism is made of low-density, high-yield-strength aluminum alloy. Three identical flexible amplification mechanisms are installed in the mounting slot of the fast reflector base 101, evenly distributed on a circumference and spaced 120° apart from each other.

[0047] The flexible amplification mechanism 104 is a multifunctional integrated unit, which can be divided into three substructures according to its main function: a flexible structure, an elliptical omnidirectional notch flexible hinge structure, and an arc-shaped unidirectional notch flexible hinge structure. The two ends of the flexible structure's rods are suspended from the columns via two cylindrical structures. The columns on both sides are fixed to the fast-reflecting mirror base 101 by screws. This can be simplified to a flexible structure with a torsional stiffness of k in the rotational direction around the fulcrum. The elliptical omnidirectional notch flexible structure is located at the end of the flexible amplification mechanism. shaft and The two degrees of freedom of the axis have the same bending stiffness, and the elliptical notch can reduce stress concentration and increase the fatigue life of the flexible hinge. The flexible amplification mechanism is a three-section integrated structure. The positional relationship of each component structure is as follows: The flexible suspension structure is located at the bottom foundation section of the flexible amplification mechanism 104. The two ends of the rod of this structure are suspended to the outer column through two cylindrical structures. The column is fixed to the corresponding mounting groove of the fast reflector base 101 by screws, providing basic support and rotation fulcrum for the entire flexible amplification mechanism; The elliptical omnidirectional notch flexible hinge structure is integrally formed at the end output section of the flexible amplification mechanism 104. It is located on the force and motion transmission path between the electromagnetic actuator mover 107 and the reflector 103. It is the key connection part of the flexible amplification mechanism and the electromagnetic actuator mover 107, which are fastened together by a square tenon; The arc-shaped unidirectional notch flexible hinge structure is precisely opened at the right angle bend at the end of the L-shaped rod of the flexible amplification mechanism 104. It is located between the flexible suspension structure and the elliptical omnidirectional notch flexible hinge structure. In the middle section of motion transmission, the three structures are arranged sequentially along the force and motion transmission direction of the flexible amplification mechanism, forming a continuous integrated structure from the base support end to the actuator connection end and then to the reflector action end.

[0048] The flexible magnification mechanism 104 is the core component of the fast-reflecting mirror device. It is made of aluminum alloy, which combines low elasticity and high yield strength. Other metals with similar mechanical properties, such as titanium alloys, can also be used. See the appendix for a detailed structure of the flexible magnification mechanism 104. Figure 4 As shown, three identical flexible amplification mechanisms are evenly distributed at 120° intervals on the same radius and installed in the corresponding mounting slots of the base 101. The arc-shaped unidirectional notch flexible hinge structure is located at the "right angle" of the end of the "L"-shaped rod. When subjected to external force, it can rotate around it to compensate for the parasitic motion at the end of the flexible mechanism. The flexible amplification mechanism 104 is divided into three sections. The first section is a flexible structure, a vertical straight plate structure, with connecting columns extending from both sides. Screw mounting holes are provided on the columns for fixing it to the mounting slots of the fast reflector base 101. The top of the base section is connected to the middle section via two cylindrical suspension structures, forming the rotation fulcrum of the entire mechanism; the second... The first segment is an arc-shaped unidirectional notch flexible hinge structure, with an "L"-shaped bend and an L angle of 70°. An arc-shaped unidirectional notch is opened at the bend, and the notch is in the shape of an inwardly concave arc. There are two inwardly concave arcs, and the two are symmetrical. The third segment is an elliptical omnidirectional notch flexible hinge structure, which is a horizontal straight plate structure. Its end is integrally formed with an elliptical omnidirectional notch, which is in the shape of an inwardly concave ellipse and also runs through the thickness direction of the rod. The end of the segment is processed with a square tenon structure. The whole structure is a "Z"-shaped spatial structure.

[0049] lever arm of flexible amplification mechanism , The major axis *a* and minor axis *b* of the elliptical notch, the radius *R* of the arc-shaped notch, the minimum cross-section *s* of the flexible hinge, and the radius *d* and height *h* of the flexible fulcrum cylindrical structure are particularly important. The selection of the lever arm affects the magnification factor of the flexible amplification mechanism and the mass of the fast-reflecting mirror motion assembly, while the selection of the radius *d* and height *h* affects the stiffness of the fast-reflecting mirror motion assembly. Choosing appropriate lever arms, radii *d*, and height *h* balances the relationship between stroke and moment of inertia. Furthermore, by selecting appropriate major axis *a*, minor axis *b*, and minimum cross-section *s*, the rotation of the elliptical omnidirectional notch flexible hinge is optimized. shaft and The stiffness of the shaft and stress concentration are considered. Based on this, an appropriate radius R is selected to optimize the compensation effect for parasitic motion at the end of the flexible mechanism. Finally, because the effects of various parameters are heavily coupled, they need to be adjusted collaboratively according to requirements to optimize the relationship between the stroke and natural frequency of the fast-reflecting mirror device.

[0050] Electromagnetic actuator: The electromagnetic actuator consists of a permanent magnet 105, a resin layer 106, an electromagnetic actuator mover 107, an iron core 108, a coil frame 109, and a coil 110. In this embodiment, the actuator part of the fast reflector device is composed of three sets of identical electromagnetic actuators. The three sets of electromagnetic actuators are installed in the mounting groove of the fast reflector base 101, and are evenly distributed around the same circumference at 120° intervals. The electromagnetic actuators are positioned by the iron core and the boss in the mounting groove of the fast reflector base 101, and are bonded together by epoxy resin adhesive.

[0051] In summary, this invention provides a large-stroke, high-bandwidth, fast-reflecting mirror device, comprising a fast-reflecting mirror base, a displacement sensor, a reflector, a flexible amplification mechanism, and an electromagnetic actuator. The controlled target (i.e., the reflector orbiting...) Axis rotation, The rotation of the axis and the yaw in the z-direction are converted into applied voltages for three sets of electromagnetic actuators through a driving coordinate transformation. These voltages drive the actuator movers to generate rotational motion around a fulcrum in the flexible amplification mechanism. The end of the flexible amplification mechanism is simplified to a displacement along the z-direction under the compensation of a circular arc-shaped unidirectional notch flexible hinge. Finally, through geometric relationships, this displacement is transformed into a reflection around the mirror. axis, The movement along the axis and in the z-direction, with three degrees of freedom, adjusts the spatial orientation of the beam and the position of the reflection point.

[0052] It also includes a magnetic shielding component 111, which is a ring structure made of permalloy material with high magnetic permeability. It is sleeved on the outside of the electromagnetic actuator and fixed to the fast reflector base 101 by bolts. A gap of 2-3 mm is reserved between the inner wall of the magnetic shielding component 111 and the outer wall of the electromagnetic actuator. The gap is filled with flexible insulating material. The flexible insulating material is a polyimide (PI) film. The height of the magnetic shielding component 111 is consistent with the height of the electromagnetic actuator. It can reduce the leakage magnetic field strength generated by the electromagnetic actuator to below the allowable value of the external environment and avoid magnetic interference to the precision electronic components around the device. The magnetic shielding component 111 adopts a ring integrated structure. The overall outline matches the circumferential distribution of the three sets of electromagnetic actuators, ensuring that it can completely wrap the outer area of ​​the electromagnetic actuator and form a fully circumferential magnetically shielded space for the electromagnetic actuator. The material used is permalloy with high magnetic permeability. In a weak magnetic field environment, permeability is much higher than that of ordinary ferromagnetic materials, effectively guiding the leakage magnetic flux generated by the electromagnetic actuator to close along the shielding assembly body, significantly reducing the outward diffusion of magnetic field strength. Compared to traditional pure iron or silicon steel sheet shielding materials, permalloy has the advantages of both low coercivity and high magnetic saturation density, avoiding residual magnetic interference generated by the shielding assembly itself. Furthermore, it is less prone to shielding performance degradation due to hysteresis during long-term use. The magnetic shielding assembly 111 is connected to the fast reflector base 101 by bolt fastening. Threaded holes are pre-drilled at corresponding positions on the base, and the bolts are made of stainless steel to avoid introducing additional magnetic impurities. During installation, the positioning pins engage with the base boss to ensure that the coaxiality error between the component and the electromagnetic actuator does not exceed 0.1mm. This ensures that the shielding area uniformly covers all leakage magnetic sources of the actuator. In practical applications, fast reflector devices often work in conjunction with sensitive components such as laser emitters, photodetectors, and high-precision displacement controllers. The operating accuracy of these components is extremely sensitive to magnetic field interference. The introduction of the magnetic shielding component 111 ensures that these components can still operate stably when close to the electromagnetic actuator without increasing the installation distance of the components, thereby reducing the size of the entire optical system. At the same time, the design of this component does not require structural modifications to the electromagnetic actuator itself, has strong compatibility, and can be adapted to permanent magnet biased magnetoresistive actuators of different specifications, providing convenience for subsequent optimization and upgrades of the device.

Claims

1. A fast-reflecting mirror device with a long stroke and high bandwidth, characterized in that: The system includes a fast reflector base (101), a displacement sensor (102), a reflector (103), a flexible amplification mechanism (104), and an electromagnetic actuator. The electromagnetic actuator consists of a permanent magnet (105), a resin layer (106), an electromagnetic actuator mover (107), an iron core (108), a coil frame (109), and a coil (110). The reflector (103) is securely connected to three sets of flexible amplification mechanisms (104). Each set of flexible amplification mechanisms (104) is securely connected to the electromagnetic actuator mover (107) at its rear. The three sets of electromagnetic actuators are evenly distributed along the circumference. The three sets of coils (110) are fixed to the fast reflector base (101). Driving voltages are applied to the three sets of coils (110) to generate a magnetic flux difference between the upper and lower working air gaps of the electromagnetic actuator mover (107). This drives the electromagnetic actuator mover (107) to rotate and deform the flexible amplification mechanism (104), thereby driving the reflector (103) to produce yaw and displacement motion. The displacement sensors (102) are three identical eddy current sensors, evenly distributed along the circumference and fixed to the fast reflector base (101) by set screws. The height of the three sets of displacement sensors (102) is along the... The probe is adjustable and is equidistant from the back of the reflector (103). It is used to detect the linear displacement changes of three points on the back of the reflector (103). The coordinate transformation is used to calculate the rotation of the reflector (103) around the back. shaft and The yaw angle of the axis and along Linear displacement in the direction.

2. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 1, characterized in that: The reflector (103) is made of metal material in one piece, with a mirror structure on the upper surface and a bottom surface that is fastened to three sets of flexible magnification mechanisms (104).

3. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 2, characterized in that: The flexible amplification mechanism (104) is a multifunctional integrated unit. Its front end is connected to the reflector (103) via a positioning pin, and its rear end is fastened to the electromagnetic actuator mover (107) via a tenon joint. Both sides of its bottom end are fixed to the fast reflector base (101) via screws. This mechanism enables motion transmission and stroke amplification, and allows for motion transmission along the path of the reflector. shaft and Flexible deformation of the axis degree of freedom and the parasitic circular motion at the end of the compensating flexible amplification mechanism.

4. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 1, characterized in that: The permanent magnet (105) is symmetrically distributed above and below the electromagnetic actuator mover (107), with its upper or lower end fastened to the iron core (108) and its side fastened to the resin layer (106). The resin layer (106) is used to fix the permanent magnet (105) and guide the magnetic flux path. The coil frame (109) is used to support and fix the coil (110) and to provide insulation.

5. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 4, characterized in that: The fast reflector base (101) is made of aluminum alloy. The base has mounting slots for an electromagnetic actuator, a flexible amplification mechanism (104), a displacement sensor (102), and mounting holes for fixing the base. The displacement sensor (102) can be replaced by a capacitive sensor or a photoelectric displacement sensor.

6. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 5, characterized in that: The reflector (103) is made of microcrystalline aluminum, titanium, beryllium or structural steel. The back is designed with positioning holes and reinforcing ribs. The positioning holes are used to position and install the flexible magnification mechanism (104) through pin holes. The reinforcing ribs are used to ensure the rigidity of the mirror while reducing weight.

7. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 1, characterized in that: The flexible amplification mechanism (104) is made of a metal material such as aluminum alloy or titanium alloy that has both low elastic modulus and high yield strength. It includes a flexible structure, an elliptical omnidirectional notch flexible hinge structure, and an arc-shaped unidirectional notch flexible hinge structure. The two ends of the rod of the flexible structure are suspended from the column through two cylindrical structures. The column is fixed to the fast reflector base (101) by screws. The elliptical omnidirectional notch flexible hinge structure is located at the end of the flexible amplification mechanism (104). shaft and The axis has the same bending stiffness in both degrees of freedom. The arc-shaped unidirectional notch flexible hinge structure is located at the right angle at the end of the "L"-shaped member and is used to compensate for parasitic motion at the end of the flexible mechanism.

8. The fast-reflecting mirror device with a large stroke and high bandwidth according to claim 7, characterized in that: The electromagnetic actuator is positioned by the boss in the mounting groove of the fast reflector base (101) via the iron core (108) and is bonded together with epoxy resin adhesive.

9. A fast-reflecting mirror device with a large stroke and high bandwidth according to claim 8, characterized in that: Three sets of electromagnetic actuators are evenly distributed on a circle, spaced 120° apart. Their points of action are located on a circle with a radius of 10mm, arranged clockwise. The point of action of electromagnetic actuator number 1 is located at... On the shaft; three sets of displacement sensors (102) are evenly distributed on a circle concentric with the electromagnetic actuator, arranged at intervals from the electromagnetic actuator, in a clockwise direction, with displacement sensor No. 2 (102) on... On the shaft, the radius of the sensor distribution circle is the same as the radius of the electromagnetic actuator's point of action, both being 10mm.

10. A fast-reflecting mirror device with a large stroke and high bandwidth according to claim 9, characterized in that: It also includes a magnetic shielding assembly (111), which is a ring structure made of permalloy material with high magnetic permeability. It is sleeved on the outside of the electromagnetic actuator and fixed to the fast reflector base (101) by bolts. A gap of 2-3 mm is reserved between the inner wall of the magnetic shielding assembly (111) and the outer wall of the electromagnetic actuator. The gap is filled with flexible insulating material. The height of the magnetic shielding assembly (111) is the same as the height of the electromagnetic actuator. It can reduce the leakage magnetic field strength generated by the electromagnetic actuator to below the allowable value of the external environment and avoid magnetic interference to the precision electronic components around the device.

Images