Two-dimensional large-rotation-angle high-bandwidth laser galvanometer

Abstract

The utility model discloses a two-dimensional large-rotation-angle high-bandwidth laser galvanometer which comprises a working mirror body, a small reflecting mirror, a flexible vibrating sheet, a fast-axis base, a slow-axis base, a fast-axis voice coil motor and a slow-axis voice coil motor. The working mirror body and the small reflecting mirror are respectively mounted on two sides of the flexible vibrating sheet, two ends of the flexible vibrating sheet are fixedly mounted on the fast axis base, the connecting line of the two mounting positions is an x axis, the fast axis base is connected with rotating ends of two cross spring bearings mounted in the y axis direction, and fixed ends of the two cross spring bearings are fixedly mounted on the slow axis base; the four slow-axis voice coil motors are uniformly distributed between the fast-axis base and the slow-axis base in the circumferential direction, the two fast-axis voice coil motors are arranged between the flexible vibration sheet and the slow-axis base and are symmetric about the x axis, the connecting line of the two fast-axis voice coil motors is on the y axis, and a light source and a photoelectric sensor are further installed on the slow-axis base and are arranged opposite to the small reflecting mirror. According to the utility model, the rotation angle measurement range and the measurement precision of the fast reflecting mirror are effectively improved.

Description

Technical Field

[0001] The utility model relates to the technical field of precision optical galvanometers, in particular to a two-dimensional large-angle high-bandwidth laser galvanometer. Background Art

[0002] Two-dimensional laser galvanometers are key components in optical scanning systems, controlling the direction of the scanning beam. In particular, in LiDAR systems, two-dimensional lasers are used in laser emission scanning systems to control the beam's scanning sequence across the target. With the advancement of science and technology, the requirements for two-dimensional laser galvanometers in the optical field have also increased, requiring them to have a larger angular measurement range and higher measurement accuracy. Utility Model Content

[0003] The purpose of the utility model is to provide a two-dimensional large-angle high-bandwidth laser galvanometer to solve the problems existing in the above-mentioned prior art and effectively improve the angle measurement range and measurement accuracy of the fast reflection mirror.

[0004] To achieve the above purpose, the present invention provides the following solutions:

[0005] The utility model provides a two-dimensional large-angle high-bandwidth laser galvanometer, comprising a working mirror body, a small reflecting mirror, a flexible oscillating piece, a fast-axis base, a slow-axis base, a fast-axis voice coil motor and a slow-axis voice coil motor;

[0006] The working mirror body and the small reflector are respectively mounted on both sides of the flexible vibrating plate, and both ends of the flexible vibrating plate are fixedly mounted on the fast axis base, and the line connecting the two mounting positions is the x-axis. The fast axis base is connected to the rotating ends of two cross spring bearings mounted in the y-axis direction, and the fixed ends of the two cross spring bearings are mounted and fixed on the slow axis base;

[0007] The four slow-axis voice coil motors are evenly distributed between the fast-axis base and the slow-axis base along the circumferential direction, the slow-axis magnetic steel of the slow-axis voice coil motor is mounted on the fast-axis base, and the slow-axis coil of the slow-axis voice coil motor is mounted on the slow-axis base;

[0008] The two fast-axis voice coil motors are arranged between the flexible vibrating piece and the slow-axis base and are symmetrical about the x-axis, and the line connecting the two is on the y-axis. The fast-axis magnets of the fast-axis voice coil motor are mounted on the flexible vibrating piece, and the fast-axis coils of the fast-axis voice coil motor are mounted on the slow-axis base.

[0009] A light source and a photoelectric sensor are also mounted on the slow axis base. The light source and the photoelectric sensor are arranged opposite to the small reflector and form a reflective angle measurement component together with the small reflector.

[0010] Preferably, it further comprises a circuit board, which is mounted on the slow axis base, and the fast axis coil, the slow axis coil, the light source and the photoelectric sensor are all electrically connected to the circuit board.

[0011] Preferably, it further comprises an upper cover, which is fixedly mounted on the slow axis base, and a through hole corresponding to the working mirror body is provided in the middle of the upper cover.

[0012] Preferably, it further comprises a rear cover plate, which is fixedly mounted on a side of the slow axis base facing away from the flexible vibrating piece, and the circuit board is arranged between the slow axis base and the rear cover plate.

[0013] Preferably, a wiring hole is provided on the slow axis base, and the wires connecting the slow axis coil and the fast axis coil to the circuit board pass through the wiring hole.

[0014] Preferably, the angles between the diagonals of the installation positions of the four slow-axis voice coil motors and the x-axis and y-axis are 45°.

[0015] Preferably, the flexible vibrating piece is fixed on the fast axis base by screws.

[0016] Preferably, the rotating end of the cross spring bearing is fixed to the fast axis base by screws, and the fixed end of the cross spring bearing is pressed against the slow axis base by an upper pressure plate, and the upper pressure plate is fixed to the slow axis base by screws.

[0017] Compared with the prior art, the utility model has achieved the following technical effects:

[0018] The utility model provides a two-dimensional large-angle, high-bandwidth laser galvanometer, which adopts a flexible vibrating piece and a cross spring bearing as a supporting structure to constrain the freedom of the moving parts and complete the rotation around the x-axis and y-axis, thereby improving the angular range of the fast reflector; a photoelectric sensor, a small reflector, and a light source are used to form a reflective angle measurement component. The angle measurement component measures the deflection angle of the small reflector and feeds it back to the control system. The control system sends a signal to the voice coil motor (fast-axis voice coil motor and slow-axis voice coil motor) to complete the precise adjustment of the working mirror position. The angle measurement component effectively improves the angular measurement range and accuracy of the fast reflector.

[0019] Furthermore, four slow-axis voice coil motors are evenly distributed between the fast-axis base and the slow-axis base, with the diagonal of their installation position at an angle of 45° to the x-axis and y-axis. This layout makes the overall structure more compact, reduces the mass of the load, and reduces the rotational inertia of the moving parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0021] Figure 1 A top view of a two-dimensional large-angle, high-bandwidth laser galvanometer in an embodiment of the present invention;

[0022] Figure 2 A bottom view of a two-dimensional large-angle, high-bandwidth laser galvanometer in an embodiment of the present utility model;

[0023] Figure 3 A cross-sectional view of a two-dimensional large-angle, high-bandwidth laser galvanometer in an embodiment of the present invention;

[0024] Figure 4 Schematic diagram of the coordinate axes of a two-dimensional large-angle, high-bandwidth laser galvanometer in an embodiment of the present utility model;

[0025] Figure 5 This is a schematic diagram of the installation structure of the circuit board and the slow axis base in the embodiment of the utility model;

[0026] Figure 6 Schematic diagram of the coordinate axes of the axonometric measurement of the two-dimensional large-angle and high-bandwidth laser galvanometer in the embodiment of the present invention;

[0027] Figure 7 Schematic diagram of the structure of the reflective angle measurement component in the embodiment of the present utility model.

[0028] In the figure: 1-upper cover, 2-slow axis base, 3-rear cover, 4-cross spring bearing, 5-working mirror, 6-small reflector, 7-fast axis magnet, 8-fast axis voice coil motor, 9-flexible vibrating piece, 10-fast axis coil, 11-upper pressure plate, 12-circuit board, 13-slow axis voice coil motor, 14-fast axis base, 15-photoelectric sensor, 16-light source, 17-screw. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] The purpose of the utility model is to provide a two-dimensional large-angle high-bandwidth laser galvanometer to solve the problems existing in the prior art and effectively improve the angle measurement range and measurement accuracy of the fast reflection mirror.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific implementation methods.

[0032] like Figure 1-Figure 7 As shown, the utility model provides a two-dimensional large-angle high-bandwidth laser galvanometer, including a working mirror body 5, a small reflector 6, a flexible vibrating piece 9, a fast-axis base 14, a slow-axis base 2, a fast-axis voice coil motor 8 and a slow-axis voice coil motor 13;

[0033] The working mirror body 5 and the small reflector 6 are respectively mounted on both sides of the flexible vibrating plate 9. The two ends of the flexible vibrating plate 9 are fixedly mounted on the fast axis base 14. The line connecting the two mounting positions is the x-axis. The fast axis base 14 is connected to the rotating ends of the two cross spring bearings 4 mounted in the y-axis direction. The fixed ends of the two cross spring bearings 4 are mounted and fixed on the slow axis base 2.

[0034] Four slow-axis voice coil motors 13 are evenly distributed between the fast-axis base 14 and the slow-axis base 2 along the circumferential direction. The slow-axis magnetic steel of the slow-axis voice coil motor 13 is installed on the fast-axis base 14, and the slow-axis coil of the slow-axis voice coil motor 13 is installed on the slow-axis base 2.

[0035] Two fast-axis voice coil motors 8 are arranged between the flexible vibrating piece 9 and the slow-axis base 2 and are symmetrical about the x-axis, and the line connecting the two is on the y-axis. The fast-axis magnet 7 of the fast-axis voice coil motor 8 is installed on the flexible vibrating piece 9, and the fast-axis coil 10 of the fast-axis voice coil motor 8 is installed on the slow-axis base 2.

[0036] A light source 16 and a photoelectric sensor 15 are also mounted on the slow axis base 2 . The light source 16 and the photoelectric sensor 15 are arranged opposite to the small reflector 6 , and together with the small reflector 6 , they form a reflective angle measurement component.

[0037] A flexible diaphragm 9 is mounted orthogonally to two cross-spring bearings 4 on the slow-axis base 2, along the x-axis and y-axis, respectively. Four slow-axis voice coil motors 13 are evenly distributed between the fast-axis base 14 and the slow-axis base 2, centered at the coordinate origin O. The diagonals of the four slow-axis voice coil motors 13 are positioned at 45° angles to the x-axis and y-axis, respectively. This layout makes the mechanical structure more compact and facilitates the miniaturization of the overall laser galvanometer structure. The four slow-axis voice coil motors 13 drive the working mirror 5 to rotate about the cross-spring bearings 4, thereby rotating the working mirror 5 about the y-axis. The two fast-axis voice coil motors 8 drive the flexible diaphragm 9, which in turn drives the working mirror 5 about the x-axis. A small reflector 6 and the working mirror 5 are mounted on either side of the flexible diaphragm 9, respectively. Their deflection angles are identical, meaning the deflection angle of the working mirror 5 can be measured by a reflective angle measurement assembly consisting of a photoelectric sensor 15, the small reflector 6, and a light source 16.

[0038] In this embodiment, the photoelectric sensor 15, light source 16, and small reflector 6 form a reflective angle measurement assembly, providing angle feedback information to the control system. Furthermore, the photoelectric sensor 15 is not susceptible to electromagnetic interference and is less affected by temperature fluctuations. Therefore, this angle measurement assembly effectively improves the angle measurement range and accuracy of the fast reflector.

[0039] This embodiment uses a flexible vibrator 9 and a cross spring bearing 4 as a supporting structure to constrain the freedom of the moving parts and complete the rotation around the x-axis and y-axis, thereby improving the angular range of the fast reflector; a photoelectric sensor 15, a small reflector 6, and a light source 16 are used to form a reflective angle measurement component. The angle measurement component measures the deflection angle of the small reflector 6 and feeds it back to the control system. The control system sends a signal to the voice coil motor (fast-axis voice coil motor 8 and slow-axis voice coil motor 13) to complete the precise adjustment of the position of the working mirror body 5. The angle measurement component effectively improves the angular measurement range and accuracy of the fast reflector.

[0040] The slow axis base 2 described in this embodiment is the foundation of the fixed part of the laser galvanometer and should have sufficient rigidity so that the reaction force of the voice coil motor (fast axis voice coil motor 8 and slow axis voice coil motor 13) does not affect the vibration mode of the slow axis base 2.

[0041] In this embodiment, the elastic deformation of the flexible vibrator 9 and the spring in the cross spring bearing 4 is used to realize the rotation of the moving part of the fast reflector around the x-axis and the y-axis. The rotation angle around the x-axis is ±10°, and the rotation angle around the y-axis is ±6.25°. Under the excitation of the fast-axis voice coil motor 8, the flexible vibrator 9 rotates around the x-axis in the first-order resonant state, thereby driving the working mirror body 5 to rotate. When the cross spring bearing 4 is working, it is achieved by the relative rotation of the fixed end of the cross spring bearing and the rotating end of the cross spring bearing. The rotation process in both directions is frictionless. In addition, the flexible vibrator 9 has the characteristics of large rotation angle and high bandwidth, and the cross spring bearing 4 has the characteristics of strong load-bearing capacity and high rotation accuracy. In addition, when the laser galvanometer is powered off, the working mirror body 5 can automatically return to the middle position under the elastic action of the flexible vibrator 9 and the cross spring bearing 4. These two flexible supports can effectively improve the stability of the laser galvanometer in the power-off state.

[0042] In this embodiment, a circuit board 12 is further included. The circuit board 12 is mounted on the slow axis base 2 . The fast axis coil 10 , the slow axis coil, the light source 16 and the photoelectric sensor 15 are all electrically connected to the circuit board 12 .

[0043] In this embodiment, an upper cover 1 is further included. The upper cover 1 is fixedly mounted on the slow axis base 2 . A through hole corresponding to the working mirror body 5 is provided in the middle of the upper cover 1 .

[0044] In this embodiment, a rear cover plate 3 is further included. The rear cover plate 3 is fixedly mounted on a side of the slow axis base 2 facing away from the flexible vibrating piece 9 . The circuit board 12 is disposed between the slow axis base 2 and the rear cover plate 3 .

[0045] In this embodiment, the slow axis base 2 is provided with wiring holes, through which the wires connecting the slow axis coil and the fast axis coil 10 to the circuit board 12 pass. The wires connecting the coils can be soldered to the circuit board 12 through the wiring holes, which can effectively protect the wires.

[0046] In this embodiment, the flexible vibrator 9 is mounted and fixed to the fast-axis base 14 via screws 17. The rotating end of the cross spring bearing 4 is also mounted and fixed to the fast-axis base 14 via screws 17. The fixed end of the cross spring bearing 4 is pressed against the slow-axis base 2 via an upper pressure plate 11, and the upper pressure plate 11 is also mounted and fixed to the slow-axis base 2 via screws 17. During installation, a certain preload force is required to the screws 17 to adjust the mechanical resonance of the flexible vibrator 9 and the gaps between the cross spring bearing 4, the upper pressure plate 11, and the slow-axis base 2.

[0047] The utility model adopts a flexible vibrating piece as the supporting component of the fast axis, and a cross spring bearing as the supporting component of the slow axis of the galvanometer. The flexible vibrating piece utilizes its own mechanical resonance characteristics to drive the working mirror body to undergo angular deflection; the cross spring bearing is a flexible support structure composed of spring pieces with a simple structure and a relatively regular shape. Its rotation center coincides with the geometric center axis, and it works by utilizing the elastic deformation of the elastic thin sheets uniformly distributed on the circumference and radial direction; under torsional load, it can achieve rotation within a limited angular range around its rotation center. Both the flexible vibrating piece and the cross spring bearing have the same characteristics as the flexible hinge, such as no friction, no gap, and small space size. In addition, the flexible vibrating piece and the cross spring bearing also have the advantages of a large deflection range and high rotation accuracy, making them widely used in precision machinery, precision measuring instruments, medical equipment, etc.

[0048] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only intended to help understand the method and core concept of the present invention. At the same time, those skilled in the art will find that the specific implementation methods and application scopes may vary based on the concept of the present invention. In summary, the contents of this specification should not be construed as limiting the present invention.

Claims

1. A two-dimensional large-angle, high-bandwidth laser galvanometer, characterized by: It includes a working mirror body, a small reflecting mirror, a flexible vibrating piece, a fast-axis base, a slow-axis base, a fast-axis voice coil motor and a slow-axis voice coil motor; The working mirror body and the small reflector are respectively mounted on both sides of the flexible vibrating plate, and both ends of the flexible vibrating plate are fixedly mounted on the fast axis base, and the line connecting the two mounting positions is the x-axis. The fast axis base is connected to the rotating ends of two cross spring bearings mounted in the y-axis direction, and the fixed ends of the two cross spring bearings are mounted and fixed on the slow axis base; The four slow-axis voice coil motors are evenly distributed between the fast-axis base and the slow-axis base along the circumferential direction, the slow-axis magnetic steel of the slow-axis voice coil motor is mounted on the fast-axis base, and the slow-axis coil of the slow-axis voice coil motor is mounted on the slow-axis base; The two fast-axis voice coil motors are arranged between the flexible vibrating piece and the slow-axis base and are symmetrical about the x-axis, and the line connecting the two is on the y-axis. The fast-axis magnets of the fast-axis voice coil motor are mounted on the flexible vibrating piece, and the fast-axis coils of the fast-axis voice coil motor are mounted on the slow-axis base. A light source and a photoelectric sensor are also mounted on the slow axis base. The light source and the photoelectric sensor are arranged opposite to the small reflector and form a reflective angle measurement component together with the small reflector.

2. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 1, characterized in that: It also includes a circuit board, which is mounted on the slow axis base. The fast axis coil, the slow axis coil, the light source and the photoelectric sensor are all electrically connected to the circuit board.

3. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 1, characterized in that: It also includes an upper cover, which is fixedly mounted on the slow axis base, and a through hole corresponding to the working mirror body is provided in the middle of the upper cover.

4. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 2, characterized in that: It also includes a rear cover plate, which is fixedly mounted on a side of the slow axis base facing away from the flexible vibrating piece, and the circuit board is arranged between the slow axis base and the rear cover plate.

5. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 4, characterized in that: The slow axis base is provided with a wiring hole, and the wires connecting the slow axis coil and the fast axis coil with the circuit board pass through the wiring hole.

6. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 1, characterized in that: The included angles between the diagonal lines of the installation positions of the four slow-axis voice coil motors and the x-axis and y-axis are 45°.

7. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 1, characterized in that: The flexible vibration piece is fixed on the fast axis base by screws.

8. The two-dimensional large-angle, high-bandwidth laser galvanometer according to claim 1, characterized in that: The rotating end of the cross spring bearing is fixed on the fast axis base by screws, and the fixed end of the cross spring bearing is pressed on the slow axis base by an upper pressure plate, and the upper pressure plate is fixed on the slow axis base by screws.

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