Push-pull type piezoelectric ultra-high bandwidth fast reflecting mirror device

Abstract

The invention relates to a push-pull type piezoelectric ultra-high bandwidth fast reflecting mirror device, and belongs to the technical field of light beam scanning and precise optical electromechanical control. Comprising a platform of a base, a low-side piezoelectric actuator, a flexible supporting ring and a high-side piezoelectric actuator which are sequentially connected from bottom to top; a light source and a photoelectric sensor are arranged on a platform of the base; the light source and the photoelectric sensor are arranged on two sides of the metal plane mirror; the low-side piezoelectric actuators and the high-side piezoelectric actuators are coaxially arranged to form actuator sets, and the actuator sets are arranged in a circumferential array mode. The flexible supporting ring is connected with the side face of the side wall of the base through a plurality of supporting hinges, and the upper end of the high-side piezoelectric actuator is connected with the top face of the side wall of the base through a steel beam. The structure complexity is simplified, the mechanical resonant frequency of the structure is improved, the system has the advantages of high linearity and stability, and the system bandwidth and the deflection angle measurement precision are improved.

Description

Technical Field

[0001] This invention relates to a reflector device, belonging to the field of beam scanning and precision opto-mechanical control technology. Background Technology

[0002] Fast Steering Mirrors (FSMs) are key components of photoelectric precision tracking and beam stabilization systems, widely used in laser communication, beam scanning, adaptive optics, and high-resolution imaging. FSMs are primarily used to precisely adjust the propagation direction of a beam. Their core function is to drive an actuator to move according to a control signal, and through appropriate mechanical or structural constraints, cause the mirror to deflect in the corresponding direction. Based on their actuation principle, fast steering mirrors can be classified into electromagnetically driven, piezoelectrically driven, and electrostatically driven fast steering mirrors. Due to the high stiffness and large output force of piezoelectric ceramic actuators, piezoelectrically driven fast steering mirrors are widely used in high-bandwidth, high-precision control applications.

[0003] Piezoelectric ceramics, based on the inverse piezoelectric effect, exhibit minute displacements along their polarization direction under an applied electric field. Limited by the polarization principle, piezoelectric ceramics typically only expand under forward voltage. To prevent the piezoelectric actuator from detaching or even fracturing due to tensile stress during operation, preload or pre-deformation is required to provide compressive stress redundancy, enabling the mirror to contract and recover. Therefore, appropriate preload structures, such as rigid beams or rings, are usually employed to antagonize the unilateral piezoelectricity and jointly drive the mirror deflection. The natural frequency of the mirror's driving mode determines the final controllable bandwidth of the system. The mirror's mass inertia, overall structural stiffness, rotational damping, and the material's elastic modulus are the main influencing factors on the structure's natural frequency. Since excessive preload mechanism stiffness affects the system's stroke, the preload mechanism stiffness cannot be too large to ensure the expected stroke. However, low stiffness limits the mirror control bandwidth. As laser processing technology, laser communication and other applications place increasingly higher demands on the control bandwidth of beam pointing systems, the traditional single-sided piezoelectric and elastic preload drive structure limits the further improvement of the system's natural frequency, making it increasingly difficult to meet the requirements of high dynamic performance. Therefore, further improving the natural frequency and control bandwidth of the piezoelectric-driven fast reflector system has become a key problem that urgently needs to be solved in order to meet the needs of high dynamic and high-precision beam scanning applications.

[0004] Therefore, there is an urgent need to propose a push-pull piezoelectric ultra-high bandwidth fast reflector device to solve the above-mentioned technical problems. Summary of the Invention

[0005] To address the aforementioned problems, a push-pull piezoelectric ultra-high bandwidth fast reflector device is provided. A brief overview of the invention is given below to provide a basic understanding of certain aspects of the invention. It should be understood that this overview is not an exhaustive summary of the invention. It is not intended to identify key or essential parts of the invention, nor is it intended to limit the scope of the invention.

[0006] The technical solution of the present invention: A push-pull piezoelectric ultra-high bandwidth fast reflector device includes: a base platform, a low-side piezoelectric actuator, a flexible support ring, and a high-side piezoelectric actuator connected sequentially from bottom to top; a light source and a photoelectric sensor are provided on the base platform; The light source and photoelectric sensor are arranged on both sides of the metal plane mirror; Low-side piezoelectric actuators and high-side piezoelectric actuators are coaxially arranged to form actuator groups, and several actuator groups are arranged in a circumferential array; The flexible support ring is connected to the side wall of the base through several support hinges, and the upper end of the high-side piezoelectric actuator is connected to the top surface of the side wall of the base through a steel beam.

[0007] Preferably, the light source is a laser source, and the photoelectric sensor is a four-quadrant photoelectric sensor.

[0008] Preferably, the base includes: a lower base having a circular platform, on which three high sidewalls are arranged circumferentially at equal intervals, a low sidewall is provided in the middle of adjacent high sidewalls, the low sidewalls are connected to the upper base, both ends of the steel beam are respectively connected to the adjacent upper base, the middle of the steel beam is connected to the high-side piezoelectric actuator, and both ends of the support hinge are respectively connected to the flexible support ring and the side of the high sidewall.

[0009] Preferably, the flexible support ring has an inner ring mirror support ring and an outer ring drive ring structure, and the inner ring mirror support ring is connected to the outer ring drive ring through three evenly distributed flexible beams.

[0010] Preferably, the metal plane mirror is a single-stage stepped axis, with the large-diameter section of the metal plane mirror located on the upper side of the inner ring mirror support ring, and the small-diameter axis section of the metal plane mirror inserted into the inner diameter of the inner ring mirror support ring, and the inner ring mirror support ring bonded to the metal plane mirror.

[0011] Preferably, the outer drive ring is an equilateral triangular ring structure, with the three corners of the outer drive ring connected to the upper base. The middle of the three sides of the outer drive ring is located between the corresponding low-side piezoelectric actuator and the high-side piezoelectric actuator. The outer side of the middle of the three sides of the outer drive ring is connected to the inner side wall of the high side wall through a support hinge. The height of the high side wall is greater than the installation height of the outer drive ring.

[0012] Preferably, piezoelectric pads are provided at both the upper and lower ends of both the low-side piezoelectric actuator and the high-side piezoelectric actuator.

[0013] Preferably, the piezoelectric pads on the drive side of the high-side piezoelectric actuator and the low-side piezoelectric actuator are connected to the upper and lower surfaces of the flexible support ring, respectively; the piezoelectric pad on the non-drive side of the high-side piezoelectric actuator is connected to the middle of the steel beam; and the piezoelectric pad on the non-drive side of the low-side piezoelectric actuator is connected to the lower base.

[0014] Preferably, the lower base platform is provided with three circumferentially distributed slides, and the lower side of the slides is provided with threaded through holes. The non-driving side piezoelectric pad of the low-side piezoelectric actuator is slidably disposed in the slides, and the preload screw passes through the threaded through holes and contacts the lower end face of the non-driving side piezoelectric pad of the low-side piezoelectric actuator.

[0015] The present invention has the following beneficial effects: 1. This invention proposes a complementary dual piezoelectric drive method, which simplifies the structural complexity and improves the degree of structural integration compared with the traditional single-sided drive and rigid preload mechanism. It uses the piezoelectric stiffness itself as the main stiffness of the system, which increases the mechanical resonant frequency of the structure. At the same time, the system stroke is decoupled from the stiffness of the preload mechanism, so that the system stroke remains basically unchanged while increasing the bandwidth. In addition to increasing the natural frequency, this drive method also has the advantages of high linearity and stability.

[0016] 2. This invention adopts an integrated photoelectric sensing scheme, which integrates the sensing signal processing circuit into the fast-reflecting mirror device, significantly improving the system bandwidth and deflection angle measurement accuracy.

[0017] 3. This invention achieves closed-loop servo control at the kilohertz or kilohertz level through closed-loop feedback compensation control, thereby improving the dynamic response capability of the fast-reflecting mirror device while maintaining the basic stroke.

[0018] 4. This invention utilizes the parameter consistency of dual piezoelectric devices and improves the linearity of the drive link through a complementary differential drive structure. It can suppress common-mode parameter drift, achieve automatic compensation for thermally induced changes, and reduce nonlinear effects such as creep and hysteresis, thereby improving system stability and repeatability. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a push-pull piezoelectric ultra-high bandwidth fast reflector provided by the present invention; Figure 2 This is a cross-sectional schematic diagram of a push-pull piezoelectric ultra-high bandwidth fast reflector provided by the present invention; Figure 3 This is a schematic diagram of a push-pull piezoelectric fast-reflecting mirror driving method provided by the present invention; Figure 4 This is a mathematical model diagram of a push-pull piezoelectric actuator provided by the present invention; Figure 5This is a top view of a push-pull piezoelectric ultra-high bandwidth fast reflector provided by the present invention; Figure 6 This is a perspective view of a push-pull piezoelectric ultra-high bandwidth fast reflector provided by the present invention. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention is described below with reference to specific embodiments shown in the accompanying drawings. However, it should be understood that these descriptions are merely exemplary and not intended to limit the scope of the invention. Furthermore, descriptions of well-known structures and technologies are omitted in the following description to avoid unnecessarily obscuring the concept of the invention.

[0021] Specific implementation method one: Combining Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device, comprising: a high-side piezoelectric actuator 2, a support hinge 3, a low-side piezoelectric actuator 4, a light source 7, a photoelectric sensor 8, a flexible support ring 10, a metal plane mirror 11, a steel beam 13, and a base, wherein the steel beam 13 is a pre-tensioned steel beam. The base platform, the low-side piezoelectric actuator 4, the flexible support ring 10, and the high-side piezoelectric actuator 2 are connected sequentially from bottom to top; a light source 7 and a photoelectric sensor 8 are installed on the base platform; The light source 7 and the photoelectric sensor 8 are arranged on both sides below the metal plane mirror 11; The low-side piezoelectric actuator 4 and the high-side piezoelectric actuator 2 are coaxially arranged to form an actuator group, and several actuator groups are arranged in a circumferential array. Due to the good symmetry of the drive layout, the natural frequency of the mirror deflection around the two-dimensional rotation axis is almost the same. The flexible support ring 10 is connected to the side wall of the base through several support hinges 3, and the upper end of the high-side piezoelectric actuator 2 is connected to the top surface of the side wall of the base through a steel beam 13. The planar reflector is connected to a flexible ring fixed to the base via three flexible support planes. A piezoelectric actuator is arranged above and below each support plane, forming a complementary push-pull drive structure. Both piezoelectric actuators provide elongation deformation, and through complementary push-pull, they provide differential driving force to cause the support planes to translate vertically, thereby achieving rapid and highly linear angular deflection of the mirror. Compared with traditional single-sided piezoelectric drive structures, the complementary dual-piezoelectric push-pull structure proposed in this invention effectively simplifies the design of the preload mechanism, transfers the main resonant stiffness of the system to the piezoelectric actuators themselves, significantly improves the system's inherent resonant frequency and control bandwidth, and enables ultra-high bandwidth applications of fast reflectors in the kilohertz to megahertz range. In addition to improved stiffness and resonant frequency, the push-pull differential drive, compared to single-sided drive, also has better linearity and thermal stability. When characteristics change due to environmental factors or the piezoelectric actuators' own heating, the symmetrical structure drive can cancel out common-mode interference. By suppressing common-mode nonlinearities such as thermal drift and creep, the linearity and stability of the device are improved.

[0022] Specific Implementation Method Two: Combining Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device. The light source 7 is a precision laser source, and the photoelectric sensor 8 is a four-quadrant photoelectric sensor. The light source 7 generates a precision laser to illuminate the back mirror (bottom surface of the metal plane mirror 11) of the metal reflector 11 to measure the mirror deflection. The photoelectric sensor 8 is used to measure the beam position. By measuring the position of the light spot reflected by the metal reflector 11, the mirror deflection angle is measured, achieving sensing measurement under high bandwidth applications. The mirror deflection causes the inherent laser beam on the reflector to illuminate the four-quadrant photoelectric sensor, resulting in different photocurrents at the four pins. Through operational amplifiers and digital signal acquisition circuits, these weak signals are analyzed and calculated to measure the actual mirror deflection angle. A closed-loop compensator is designed using a zero-pole cancellation method, and closed-loop servo control is completed with the mirror deflection angle converted from the photocurrent.

[0023] Specific implementation method three: Combining Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device. The base includes a lower base 5 and an upper base 12. The lower base 5 has a circular platform with three circumferentially equidistant high sidewalls. Each adjacent high sidewall has a low sidewall at its center, and the low sidewalls are equidistant, forming a sidewall. Screws 9 pass through through holes in the low sidewalls and connect to threaded holes on the lower side of the corresponding upper base 12. The two ends of a steel beam 13 are connected to adjacent upper bases 12 via bolts 14. The middle of the steel beam 13 is connected to the upper end of a high-side piezoelectric actuator 2. The two ends of a support hinge 3 are connected to the edge of a flexible support ring 10 and the side of the corresponding high sidewall, respectively. The upper base 12 and lower base 5 provide a piezoelectric base support structure, connected by three sets of screws, which clamp and fix the flexible support ring 10.

[0024] Specific implementation method four: Combination Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device. The flexible support ring 10 has an inner ring mirror support ring and an outer ring drive ring structure. The inner ring mirror support ring (circular structure) is connected to the outer ring drive ring (midpoint of the side of a triangular ring structure) via three evenly distributed flexible beams (linear structure). The flexible support ring 10 can be integrally machined using 0.5-3mm thick flexible 304 stainless steel. The flexible support ring 10 is manufactured using stainless steel sheet wire cutting technology, and consists of the inner ring mirror support ring and the outer ring drive ring connected by a flexible... The structure is composed of beams, with the inner ring glued to the metal plane mirror 11 and the outer ring fixed to the base 12 and the lower base 5 through a fit. The supporting plane of the metal plane mirror 11 is positioned in the center of the outer ring and can be flexibly displaced up and down. Due to its high lateral stiffness, this structure restricts the lateral displacement of the mirror surface. The flexible support ring 10 and the lateral flexible hinge are designed to provide lateral support stiffness, not as constraints of this scheme. This scheme mainly provides a new configuration of a fast-reflecting mirror with a push-pull dual piezoelectric differential drive. Other structural designs that provide lateral support stiffness do not change the essence of the modified structure and are still protected by this patent.

[0025] Specific Implementation Method Five: Combining Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device. The metal plane mirror 11 is a single-stage stepped shaft. The large-diameter section of the metal plane mirror 11 is located on the upper side of the inner ring mirror support ring, while the small-diameter shaft section of the metal plane mirror 11 is inserted into the inner diameter of the inner ring mirror support ring. The inner ring mirror support ring is glued to the metal plane mirror 11. The metal plane mirror 11 can generate two-dimensional fixed-axis rotation for precise beam deflection. Its bottom surface is also mirror-finished for measuring its own deflection angle. It is fixed to the flexible support ring 10 via resin structural adhesive. Three integrated flexible support planes are drawn out from the metal mirror surface and glued to the driving point of the flexible support ring 10.

[0026] Specific Implementation Method Six: Combination Figure 1-6This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device. The outer drive ring is a structure resembling an equilateral triangle. The three corners of the outer drive ring are connected to the upper base 12. The upper base 12 and the low sidewall clamp the corresponding corners of the triangular ring structure. The middle of the three sides of the outer drive ring is located between the corresponding low-side piezoelectric actuator 4 and high-side piezoelectric actuator 2. The outer sides of the middle of the three sides of the outer drive ring are connected to the inner sidewall of the high sidewall via a support hinge 3. The height of the high sidewall is greater than that of the outer ring. The installation height of the drive ring; three sets of high and low side piezoelectric actuators are arranged equidistantly around the mirror surface. Force is transmitted through the flexible support surface of the mirror surface, and the translation of each set of piezoelectric actuators along the normal direction of the mirror surface is converted into the deflection motion of the mirror surface. Different voltages are applied to each set of piezoelectric actuators through a linear power amplifier, which can make the mirror surface produce the final deflection motion; the three flexible support surfaces of the mirror surface are fixed to the mirror surface to improve the force transmission efficiency. Flexible hinges are used between the support surfaces and the mirror surface to minimize the surface shape change caused by concentrated stress on the mirror surface during the driving process.

[0027] Specific implementation method seven: Combination Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device, which also includes piezoelectric pads 1. Piezoelectric pads 1 are fixedly connected to both ends of the low-side piezoelectric actuator 4 and both ends of the high-side piezoelectric actuator 2, which ensures precise driving positioning and reduces piezoelectric stress concentration.

[0028] Specific implementation method eight: Combination Figure 1-6 This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device. The drive-side piezoelectric pad 1 of the high-side piezoelectric actuator 2 and the drive-side piezoelectric pad 1 of the low-side piezoelectric actuator 4 are both connected to the upper and lower surfaces of the center of the outer ring drive ring structure of the flexible support ring 10, respectively. The non-drive-side piezoelectric pad 1 of the high-side piezoelectric actuator 2 is connected to the middle of the steel beam 13, and the non-drive-side piezoelectric pad 1 of the low-side piezoelectric actuator 4 is connected to the lower base 5. Piezoelectricity can only provide positive voltage and thrust. The high-side piezoelectric output direction is downward, supporting the flexible ring, while the low-side piezoelectric output direction is... Upward, supporting the flexible ring below, first apply a voltage bias of 30V, for example, both have a thrust of 500N. Then, the high-side piezoelectric is superimposed with -15V, and the low-side is superimposed with +15V, so the high-side becomes a thrust of 250N and the low-side is 750N, pushing the drive point upward. Conversely, the high-side is superimposed with 15V and the low-side with -15V, driving downward. The pre-tightening steel beam 13 is used to eliminate the pre-deformation caused by the common-mode voltage bias voltage of the piezoelectric actuator, preventing excessive compressive stress from being unable to be released due to excessive stiffness, which would damage the piezoelectric. In addition, the steel beam can also eliminate the long-period common-mode deformation caused by the nonlinear hysteresis of the piezoelectric.

[0029] Specific Implementation Method Nine: Combining Figure 1-6This embodiment describes a push-pull piezoelectric ultra-high bandwidth fast reflector device, which further includes a preload screw 6. Three circumferentially distributed slides are provided on the lower base 5 platform. Threaded through holes are provided on the lower side of the slides. The non-driving side piezoelectric pad 1 of the low-side piezoelectric actuator 4 is slidably disposed within the slides. The preload screw 6 passes through the threaded through holes and contacts the lower end face of the non-driving side piezoelectric pad 1 of the low-side piezoelectric actuator 4. By rotating the preload screw 6, which is threadedly connected to the threaded hole, the extension length of the preload screw 6 is adjusted, thereby adjusting the position of the non-driving side piezoelectric pad 1 of the low-side piezoelectric actuator 4 and providing appropriate preload. Under common-mode pre-voltage bias, the high-side piezoelectric and low-side piezoelectric actuators of each group provide opposite driving voltages. When the high-side piezoelectric relatively contracts, the low-side piezoelectric relatively expands, pushing the middle support plane to generate a mirror-normal displacement.

[0030] In summary, this invention provides a push-pull piezoelectric ultra-high bandwidth fast reflector device, which can realize the reflection of metal plane mirrors around... axis, The system incorporates three degrees of freedom: axis yaw and translation along the z-axis. This increases the system's natural mechanical frequency and enables high-bandwidth closed-loop control.

[0031] Example 1: In the field of high-precision opto-electro-mechanical servo tracking, this invention is mainly used for large-stroke, high-dynamic beam pointing adjustment and tracking scanning control in precision instruments and equipment in scenarios such as precision laser processing, laser communication, and biomedical microscopic imaging.

[0032] like Figure 1 As shown, this invention provides a push-pull piezoelectric ultra-high bandwidth fast reflector device. The lower base 5 serves as the overall structural mounting base and can be installed on an air-bearing vibration isolation platform or lateral tooling. Three sets of upper bases 12 are fixed to the lower base 5 by screw sets and positioning pins, serving as the overall force transmission unit for piezoelectric stress. The three edges of the outer ring of the flexible support ring 10 are clamped and fixed by the upper and lower bases. The flexible beams extending from its three fixed edges serve as circumferential fixation for the complementary double piezoelectric mid-ends, while also exhibiting high flexibility in the mirror surface normal direction, allowing the double piezoelectric mid-ends to slide along the normal direction. The inner and outer rings of the flexible support ring 10 are connected by a beam structure. The inner ring is used to bond the metal plane reflector 11, allowing the mirror surface to deflect in two degrees of freedom.

[0033] Due to the complex low-order mode coupling in high-frequency applications, modes such as the piezoelectric actuator's own lateral elastic wave may become the lowest-order modes of the system and couple with the driving method, affecting the control bandwidth. Therefore, strong rigid constraints are required. The lateral support hinge 3, based on the flexible support ring restricting the radial movement of the piezoelectric ceramic, further improves the system's radial stiffness. By providing additional constraints, it limits the piezoelectric lateral vibration modes and increases the system's mechanical frequency.

[0034] Three sets of low-side piezoelectric ceramics 4 are installed below the flexible support ring, arranged equidistantly around the mirror surface. They contact the lower base via pads 1 and are adjusted vertically using set screws 6. Pads 1 can slide within a certain range in the grooves of the lower base. Three sets of high-side piezoelectric ceramics 2 are installed above the mirror support surface, vertically aligned with the low-side piezoelectric ceramics. A pre-tensioning steel beam 13 provides downward clamping force and is fixed to the upper base 12 with screws. Pads are used as installation aids between the high-side piezoelectric ceramics and the mirror support surface and the steel beam. The grooves in the steel beam restrict the position of the pads, completing the piezoelectric constraint. Pads are also used as installation aids between the low-side piezoelectric ceramics and the flexible support ring and the lower base.

[0035] The radial constraint of the mirror is achieved by a flexible support ring. Since the outer edge of the support ring is fixed to the base, and the inner and outer rings bonded to the mirror have high rigidity, the translational movement of the mirror in the horizontal direction is restricted. The axial rigidity of the inner and outer rings is also very large, which restricts the rotational mode of the mirror in the normal direction. When the mirror deflects in the diameter direction, the rigidity of the flexible support ring is small, and the mirror can rotate freely.

[0036] like Figure 2 A sectional view of the structure along the vertical plane of the center-piezoelectric drive side is given. Figure 3 A schematic diagram of the driving mechanism is provided. The mirror is fixed to a flexible support ring, and the outer side of the flexible support ring is fixed to the base. The flexible support plane of the mirror is aligned with the center of the outer ring of the support ring through holes. Three alignment holes allow displacement along the normal direction of the mirror. In the push-pull piezoelectric assembly, the high-side piezoelectric electrode is in close contact with the flexible support plane of the mirror, providing downward pressure; the high-side piezoelectric electrode is in close contact with the bottom surface of the flexible support ring, providing upward pressure. The two piezoelectric electrodes restrict the position of the support plane under the condition of applying a common-mode piezoelectric bias. If a negative voltage is applied to the high-side piezoelectric electrode and a positive voltage is applied to the low-side piezoelectric electrode on the basis of the bias, the upward pressure provided by the high-side decreases and the downward pressure provided by the low-side increases. The flexible support plane of the mirror generates an upward acceleration, eventually producing the expected displacement, and the mirror is guided to deflect through the flexible structure between the flexible support surface and the mirror.

[0037] To prevent the mirror's rotation axis from shifting vertically, the magnitudes of the driving displacements of the three sets of drive mechanisms must meet certain geometric constraints. For example, if we want to move along... If the axis is deflected, piezoelectric unit A should not produce displacement, while the displacements produced by piezoelectric units B and C should be equal in magnitude and opposite in direction. If the mirror surface along... If deflection occurs, the displacements produced by piezoelectric group B and piezoelectric group C should be equal, while the displacement produced by piezoelectric group A should be twice theirs, and in opposite directions. Deflections in other directions can be obtained by combining these two orthogonal deflections, which will not be elaborated here.

[0038] Figure 4A push-pull dual piezoelectric drive model is presented. Since the resonant frequency of piezoelectric elements is typically very high, at the drive frequency, it can be simplified to a linear mass-spring-damping-inverse piezoelectric model, with an equivalent mass of 1 / 3 of its own mass. The rotational inertia of the mirrors can be converted to each drive shaft through generalized coordinate transformation. This drive method does not use traditional rigid preload to provide restoring force, but instead utilizes the rigidity of the opposing piezoelectric elements themselves, significantly improving the stiffness of the drive shafts and extending the resonant frequency of the fast-reflecting mirror to the Mbps level. Because piezoelectric ceramics exhibit nonlinear factors such as hysteresis, which affect the linearity of the drive, a hysteresis inverse model is required for pre-feedforward control of the piezoelectric elements.

[0039] Sensor Configuration: To achieve closed-loop servo control by measuring the plane deflection angle, a high-bandwidth measurement scheme is required. Traditional eddy current and capacitive sensing schemes are insufficient for high dynamic requirements. Therefore, a four-quadrant photodiode is used. By measuring the reflection angle from the back of the mirror, the deflection angle of the mirror is obtained. Based on the photoelectric effect, the four-quadrant photodiode generates four quadrant photocurrents on a fixed light spot. The specific location of the light spot can be obtained through a fixed mathematical formula, and the mirror deflection angle can be calculated in reverse.

[0040] In summary, this invention provides a push-pull piezoelectric ultra-high bandwidth fast reflector device, comprising a flexible ring, a metal planar reflector, a piezoelectric actuator, a preloaded steel beam, upper and lower bases, a precision laser source, a four-quadrant sensor, and related accessories. Through a complementary driving method, the mirror surface is actuated to produce a two-degree-of-freedom deflection motion under a small vertical displacement at its end face, thereby increasing the mechanical resonant frequency of the fast reflector structure and achieving ultra-high bandwidth servo control of the fast reflector.

[0041] It should be noted that in the above embodiments, as long as the technical solutions are not contradictory, they can be permuted and combined. Those skilled in the art can exhaust all possibilities based on the mathematical knowledge of permutation and combination. Therefore, the present invention will not describe the technical solutions after permutation and combination one by one, but it should be understood that the technical solutions after permutation and combination have been disclosed by the present invention.

[0042] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A push-pull piezoelectric ultra-high bandwidth fast steering mirror device, characterized by: The base includes: The platform of the base, the low-edge piezoelectric actuator (4), the flexible support ring (10), and the high-edge piezoelectric actuator (2) are sequentially connected from bottom to top; the platform of the base is provided with a light source (7) and a photoelectric sensor (8); The light source (7) and the photoelectric sensor (8) are arranged on both sides of the metal plane mirror (11); The low-edge piezoelectric actuator (4) and the high-edge piezoelectric actuator (2) are coaxially arranged to form an actuator group, and a plurality of actuator groups are arranged in a circumferential array; The flexible support ring (10) is connected to the side wall of the base through a plurality of support hinges (3), and the upper end of the high-edge piezoelectric actuator (2) is connected to the top surface of the side wall of the base through a steel beam (13).

2. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 1, wherein: The light source (7) is a laser source, and the photoelectric sensor (8) is a four-quadrant photoelectric sensor.

3. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 1 or 2, wherein: The base includes: The lower base (5) has a circular platform, and three high side walls are arranged on the platform in a circumferential and equidistant manner; a low side wall is arranged in the middle of adjacent high side walls, the low side wall is connected to the upper base (12), the two ends of the steel beam (13) are respectively connected to adjacent upper bases (12), the middle part of the steel beam (13) is connected to the high-edge piezoelectric actuator (2), and the two ends of the support hinge (3) are respectively connected to the flexible support ring (10) and the side surface of the high side wall.

4. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 3, wherein: The flexible support ring (10) has an inner ring mirror surface support ring and an outer ring driving ring structure, and the inner ring mirror surface support ring is connected to the outer ring driving ring through three evenly distributed flexible beams.

5. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 4, wherein: The metal plane mirror (11) is a single-stage stepped shaft, the large-diameter section of the metal plane mirror (11) is located on the upper side of the inner ring mirror surface support ring, the small-diameter shaft section of the metal plane mirror (11) is inserted into the inner diameter of the inner ring mirror surface support ring, and the inner ring mirror surface support ring is glued to the metal plane mirror (11).

6. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 5, wherein: The outer ring driving ring is an equilateral triangle ring structure, the three corners of the outer ring driving ring correspond to the upper base (12), the middle part of the three edges of the outer ring driving ring is arranged between the low-edge piezoelectric actuator (4) and the high-edge piezoelectric actuator (2), the outer side of the middle part of the three edges of the outer ring driving ring is connected to the inner side of the high side wall through the support hinge (3), and the height of the high side wall is greater than the installation height of the outer ring driving ring.

7. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 6, wherein: The upper and lower ends of the low-edge piezoelectric actuator (4) and the high-edge piezoelectric actuator (2) are provided with piezoelectric pads (1).

8. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 7, wherein: The driving side piezoelectric pads (1) of the high-edge piezoelectric actuator (2) and the low-edge piezoelectric actuator (4) are respectively connected to the upper and lower surfaces of the flexible support ring (10), the non-driving side piezoelectric pad (1) of the high-edge piezoelectric actuator (2) is connected to the middle part of the steel beam (13), and the non-driving side piezoelectric pad (1) of the low-edge piezoelectric actuator (4) is connected to the lower base (5).

9. The push-pull piezoelectric ultra-high bandwidth fast steering mirror device of claim 8, wherein: The platform of the lower base (5) is provided with three circumferentially distributed slides, the lower side of the slide is provided with a threaded hole, the non-driving side piezoelectric pad (1) of the low-edge piezoelectric actuator (4) is slidingly arranged in the slide, and the pre-tightening force jack (6) is in contact with the lower end surface of the non-driving side piezoelectric pad (1) of the low-edge piezoelectric actuator (4) through the threaded hole.

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