Reflector mounting frame of resonant scanning galvanometer and resonant scanning galvanometer

Abstract

The utility model discloses a reflector mounting frame of a resonant scanning galvanometer and the resonant scanning galvanometer, and the reflector mounting frame of the resonant scanning galvanometer comprises a plurality of sub-frames which are sequentially sleeved from inside to outside, and the sub-frames are rotatably connected through a rotating shaft, the innermost sub-frame is provided with a first side face and a second side face which are opposite to each other, the first side face is provided with an inner reflecting mirror used for reflecting light source light from the interior of the scanning galvanometer, and the second side face is provided with an outer reflecting mirror used for reflecting light source light from the exterior of the scanning galvanometer. At least two adjacent sub-frames in the reflector installation frame are made of metal elastic pieces, the rotating shaft between the two adjacent sub-frames made of the metal elastic pieces and the metal elastic pieces are integrally formed, and a magnet is arranged on the first side face. By using the reflector mounting frame provided by the embodiment of the invention, the scanning field of view of the scanning galvanometer can be increased.

Description

Technical Field

[0001] This application relates to scanning galvanometers, and more particularly to a mirror mounting frame for a resonant scanning galvanometer and the resonant scanning galvanometer itself. Background Technology

[0002] Electromagnetic galvanometers, as devices for controlling the direction of beam propagation between a light source and a receiver, are widely used in fields such as space optical communication, lidar, machine vision, and laser processing due to their advantages such as high response bandwidth, high positioning accuracy, and high angular resolution.

[0003] In terms of operation, the most common electromagnetic galvanometers in existing technologies are quasi-static two-dimensional electromagnetic scanning galvanometers. Quasi-static means that both axes of this galvanometer operate at non-resonant frequencies, and the operating bandwidth in both directions is adjustable from DC drive to a certain frequency. The operating frequencies along both axes are typically between 10-30 Hz. Although quasi-static two-dimensional electromagnetic scanning galvanometers can pause at any scanning angle within their scanning range, their scanning angle range is relatively small, and because they can only achieve point-to-point scanning, they cannot be applied to the field of laser scanning imaging. Utility Model Content

[0004] To address the technical problems existing in the prior art, this application proposes a mirror mounting frame for a resonant scanning galvanometer and a resonant scanning galvanometer. By designing the sub-frame in the mirror mounting frame as a metal spring structure, the resonant scanning galvanometer can operate at the resonant frequency, thereby improving the scanning angle range.

[0005] This application provides a mirror mounting frame for a resonant scanning galvanometer, comprising multiple sub-frames nested sequentially from the inside out. The sub-frames are rotatably connected by a pivot. The innermost sub-frame has a first side and a second side facing away from each other. The first side has an inner mirror for reflecting light from a light source inside the scanning galvanometer, and the second side has an outer mirror for reflecting light from a light source outside the scanning galvanometer. At least two adjacent sub-frames in the mirror mounting frame are made of metal springs, and the pivot between two adjacent sub-frames made of metal springs is integrally formed with the metal springs. A magnet is provided on the first side. When the magnet is subjected to a preset magnetic field force, the sub-frame made of metal springs that resonates is the target sub-frame.

[0006] Optionally, the reflector mounting frame includes an inner sub-frame and an outer sub-frame, the innermost sub-frame being the innermost sub-frame, both the inner and outer sub-frames being made of metal springs, the pivot being a first shaft, the first shaft being a cantilever torsion beam, the portion of the first shaft located in the outer sub-frame being a hollow body, and the inner sub-frame being the target sub-frame.

[0007] Optionally, the reflector mounting frame includes an inner sub-frame, a middle sub-frame, and an outer sub-frame sequentially nested from the inside out. The inner sub-frame and the middle sub-frame are made of metal springs. The rotating shaft includes a second shaft located between the middle sub-frame and the inner sub-frame. The portion of the second shaft located in the middle sub-frame is a hollow body. A fixing frame is provided on the outer circumferential direction of the hollow body. The rotating shaft also includes a pin disposed between the fixing frame and the outer sub-frame. The fixing frame drives the middle sub-frame to rotate around the pin. The direction of the pin intersects with that of the second shaft. The inner sub-frame is the target sub-frame.

[0008] Optionally, the reflector mounting frame includes an inner sub-frame, a middle sub-frame, and an outer sub-frame nested sequentially from the inside out. The outer sub-frame, middle sub-frame, and inner sub-frame are all made of metal springs. The pivot includes a third axis disposed between the outer sub-frame and the middle sub-frame, which is a hollow body formed by the outer sub-frame and the middle sub-frame. The pivot also includes a fourth axis disposed between the middle sub-frame and the inner sub-frame, with the portion located in the middle sub-frame being a hollow body. The directions of the third axis and the fourth axis intersect, and the inner sub-frame and / or the middle sub-frame is the target sub-frame.

[0009] Optionally, when both the inner subframe and the intermediate subframe are target subframes, the ratio of their resonant frequencies is an integer.

[0010] Optionally, the inner sub-frame is circular, and the outer sub-frame is square.

[0011] Optionally, both the intermediate sub-frame and the fixed frame are circular ring structures.

[0012] Optionally, a mounting hole is provided in the middle of the innermost sub-frame, and the internal reflector is disposed in the mounting hole.

[0013] This application also proposes a resonant scanning galvanometer, comprising at least a light-emitting component, a coil assembly, and a base. The light-emitting component and the coil assembly are mounted on a PCB board, which is fixed to the base. A mirror rotation assembly is disposed opposite to the PCB board. The light-emitting component includes a light source and a plurality of photocells surrounding the light source. The coil assembly includes a plurality of winding coils surrounding the photocells. The resonant scanning galvanometer further includes the aforementioned mirror mounting frame, which is disposed on the opposite side of the photocells and fixed to the base by connectors. The inner mirror is opposite to the light source in the light-emitting component. A magnet disposed on a subframe of the mirror mounting frame is opposite to the winding coils. The Ampere force generated by the winding coils acts on the magnets to cause the subframes to resonate and form a target subframe.

[0014] Optionally, it also includes a washer and a clamping frame. The washer is disposed between the reflector mounting frame and the PCB board. The clamping frame and the outermost sub-frame of the reflector mounting frame have the same shape. The clamping frame has a circular hole, and a bolt is disposed in the circular hole. The bolt passes through the clamping frame, the reflector mounting frame, the washer, the PCB board, and the base.

[0015] Optionally, the frequency of the current flowing through the winding coil is the same as the natural frequency of the target subframe.

[0016] The resonant scanning galvanometer proposed in this application has a reflector mounting frame with a metal spring capable of resonance, thereby enabling the vibration of the resonant scanning galvanometer in at least one scanning direction to be in a resonant mode, which in turn improves the scanning angle range of the resonant scanning galvanometer. Attached Figure Description

[0017] The preferred embodiments of this application will now be described in further detail with reference to the accompanying drawings, wherein:

[0018] Figure 1 This is a three-dimensional structural view of the mirror mounting frame of a resonant scanning galvanometer according to an embodiment of this application;

[0019] Figure 2 yes Figure 1 A structural view of the rear side of the structure shown;

[0020] Figure 3 This is a three-dimensional structural diagram of another reflector mounting frame according to an embodiment of this application;

[0021] Figure 4 yes Figure 3 A schematic diagram of the back structure of the structure shown;

[0022] Figure 5 This is a three-dimensional structural schematic diagram of another reflector mounting frame according to an embodiment of this application;

[0023] Figure 6 yes Figure 5 A schematic diagram of the back structure of the structure shown;

[0024] Figure 7 This is a three-dimensional structural schematic diagram of a resonant scanning mirror according to an embodiment of this application;

[0025] Figure 8 yes Figure 7 Exploded view of the structure shown;

[0026] Figure 9 This is a scanning pattern of a resonant scanning mirror in an embodiment of this application, where both scanning directions are in a non-resonant state;

[0027] Figure 10 This application describes a first scanning pattern where one scanning direction of a resonant scanning mirror operates in a quasi-static state and the other scanning direction operates in a resonant state.

[0028] Figure 11 This is a second scanning pattern of a resonant scanning mirror according to an embodiment of the present application, where one scanning direction operates in a quasi-static state and the other scanning direction operates in a resonant state;

[0029] Figure 12 This is a scanning pattern of a resonant scanning mirror according to an embodiment of this application, in which both scanning directions are in a resonant state;

[0030] Figure 13 This is a scanning pattern of a resonant scanning mirror according to an embodiment of this application, in which both scanning directions are in a resonant state;

[0031] Figure 14 This is a three-dimensional structural schematic diagram of another resonant scanning mirror according to an embodiment of this application;

[0032] Figure 15 yes Figure 14 Exploded view of the structure shown;

[0033] Figure 16 This is a three-dimensional structural schematic diagram of another resonant scanning mirror according to an embodiment of this application;

[0034] Figure 17 yes Figure 16 Exploded view of the structure shown.

[0035] Explanation of reference numerals in the attached figures:

[0036] 100. Mirror mounting frame; 101. Outer sub-frame; 102. Middle sub-frame; 103. Inner sub-frame; 104. Rotating shaft; 105. Inner mirror; 106. Outer mirror; 120. Mounting hole; 107. Magnet; 1041. First shaft; 1042. Second shaft; 109. Pin; 108. Fixing frame; 1043. Third shaft; 1044. Fourth shaft; 600. Harmony Vibrating scanning galvanometer; 601, base; 612, raised edge; 602, PCB board; 603, light source; 604, photovoltaic cell; 605, winding coil; 607, washer; 608, clamping frame; 609, bolt; 6081, round hole; 6051, first winding coil; 1071, first magnet; 1072, second magnet; 110, third magnet; 111, fourth magnet; 613, light shield. Detailed Implementation

[0037] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0038] In the following detailed description, reference can be made to the accompanying drawings, which form part of this application and illustrate specific embodiments of the present application. In the drawings, similar reference numerals describe substantially similar components in different figures. Specific embodiments of the present application are described in sufficient detail below to enable those skilled in the art to implement the technical solutions of the present application. It should be understood that other embodiments may also be utilized, or structural, logical, or electrical changes may be made to the embodiments of the present application.

[0039] Figure 1 This is a three-dimensional structural view of the mirror mounting frame of a resonant scanning galvanometer according to an embodiment of this application. Figure 2 yes Figure 1 A structural view of the rear of the structure shown. Combined with... Figure 1 and Figure 2As shown, the mirror mounting frame 100 of the resonant scanning galvanometer includes multiple sub-frames nested sequentially from the inside out, such as an outer sub-frame 101, a middle sub-frame 102, and an inner sub-frame 103. The sub-frames are rotatably connected by a pivot 104. The innermost sub-frame (inner sub-frame 103) has a first side and a second side facing away from each other. The first side is provided with an inner mirror 105 for reflecting light from the light source inside the scanning galvanometer, and the second side is provided with an outer mirror 106 for reflecting light from the light source outside the scanning galvanometer. It should be noted that in some embodiments of this application, the outer mirror 106 and the inner mirror 105 can be formed by forming a single mirror body by providing coatings on its two opposite sides. In other embodiments of this application, optionally, the inner mirror and the outer mirror have different mirror bodies and are two different mirrors. The inner reflector 105 can be installed in the mounting hole 120, which is located in the middle of the innermost subframe. The mounting hole 120 can be formed by hollowing out the middle of the innermost subframe.

[0040] See also Figure 1 and Figure 2 As shown, at least two adjacent subframes in the mirror mounting frame 100 are made of metal spring clips, for example, in Figure 1 and Figure 2 In the illustrated embodiment, the outer sub-frame 101, the middle sub-frame 102, and the inner sub-frame 103 are all made of metal springs. A metal spring is a flexible metal element made of a metal material (e.g., stainless steel, spring steel, brass, titanium alloy, beryllium bronze, phosphor bronze, etc.). It typically has a specific shape and size, and is capable of deforming when subjected to external force and quickly returning to its original shape after the force is removed. Furthermore, for the reflector mounting frame 100, the pivot 104 between two adjacent sub-frames made of metal springs is integrally formed with the metal springs. A magnet 107 is provided on the first side. Under the action of the magnetic field force, the sub-frame made of metal springs that resonates is the target sub-frame. The two adjacent metal springs can be a single metal spring formed by hollowing out. In some embodiments of this application, a gap is formed between the two adjacent metal springs by hollowing out. The pivot between the two adjacent metal springs is a cantilever beam structure, which is also formed by hollowing out. Moreover, the cantilever beam structure selects different materials, strengths, and stiffnesses according to different usage scenarios, exhibiting various structural forms to achieve different frequency and angle effects. In some embodiments of this application, optionally, the thickness of the cantilever beam structure is 0.2-0.5mm, the width is 0.2-0.5mm, and the material is titanium alloy. When the target sub-frame is circular with a diameter of 10-40mm, its resonant frequency can reach 100-300Hz.

[0041] Furthermore, the magnet 107 experiences a magnetic force in the magnetic field generated by the energized coil (not shown in the figure). The energized coil can be positioned opposite the magnet 107. The magnitude and direction of the magnetic field generated by the energized coil can be controlled by adjusting the direction and magnitude of the current flowing through it, thereby altering the magnitude and direction of the magnetic force acting on the magnet. In this embodiment, by controlling the magnitude and direction of the magnetic field generated by the energized coil, the subframe made of metal spring sheets can resonate under the influence of the force on the magnet. The resonant subframe made of metal spring sheets is the target subframe.

[0042] Figure 3 This is a three-dimensional structural diagram of another reflector mounting frame according to an embodiment of this application. Figure 4 yes Figure 3 A schematic diagram of the rear structure of the shown configuration. (Combined with...) Figure 3 and Figure 4 As shown, the reflector mounting frame 100 includes an inner sub-frame 103 and an outer sub-frame 101. The innermost sub-frame 103 is located in the innermost sub-frame. Both the inner and outer sub-frames 103 are made of metal springs. The pivot 104 is a first shaft 1041, which is a cantilever torsion beam. The portion of the first shaft 1041 located on the outer sub-frame is hollow. The inner sub-frame 103 is the target sub-frame because it can resonate. The first shaft 1041 is elongated and consists of two opposing parts. The axial connecting line of these two parts passes through the inner sub-frame 103. The portion of the first shaft 1041 located on the outer sub-frame can be formed by removing a portion of the metal spring. A magnet 107 is provided on the first side of the inner subframe 103. In some embodiments of this application, the magnet 107 is optionally subjected to magnetic force, which causes the inner subframe to resonate. Since the amplitude of the metal spring is the largest when it resonates, the reflection angle of the light source light reflected by the outer reflector 106 from the outside of the scanning galvanometer can be increased, thereby increasing the scanning angle.

[0043] Figure 5 This is a three-dimensional structural diagram of another reflector mounting frame according to an embodiment of this application. Figure 6 yes Figure 5 A schematic diagram of the rear structure of the shown configuration. (Combined with...) Figure 5 and Figure 6As shown, the reflector mounting frame 100 includes an inner sub-frame 103, a middle sub-frame 102, and an outer sub-frame 101, which are sequentially nested from the inside out. The inner sub-frame 103 and the middle sub-frame 102 are made of metal springs. The rotating shaft 104 includes a second shaft 1042 and a pin 109. The second shaft is located between the middle sub-frame 102 and the inner sub-frame 103. The portion of the second shaft 1042 located in the middle sub-frame 102 is hollow. A fixing frame 108 is provided on the outer circumference of the hollow body. The pin 109 is located between the fixing frame 108 and the outer sub-frame 101. The fixing frame 108 drives the middle sub-frame 102 to rotate around the pin 109. The direction of the pin 109 intersects with that of the second shaft 1042. The inner sub-frame 103 is the target sub-frame. In this embodiment, both the intermediate sub-frame 102 and the inner sub-frame 103 are made of metal spring sheets. A fixing frame 108 is provided on the edge of the intermediate sub-frame 102, and the fixing frame 108 and the intermediate sub-frame 102 are fixedly connected. The fixing frame 108 and the outer sub-frame 101 are rotatably connected by a pin 109. Under the action of a magnetic force on the first magnet 1071, the intermediate sub-frame 102 and the inner sub-frame 103 rotate together around the pin 109. Under the action of a magnetic force on the second magnet 1072, the inner sub-frame 103 can resonate around the second shaft 1042. In some embodiments of this application, optionally, the axial direction of the second shaft 1042 is perpendicular to the axial direction of the pin 109. The pin 109 is also called a quasi-static shaft, and the operating frequency along this quasi-static shaft is typically tens of hertz; the second shaft 1042 is also called a resonant shaft, and the resonant frequency along this shaft is several hundred hertz.

[0044] As one embodiment of a mirror mounting frame, such as Figure 1 and Figure 2As shown, the reflector mounting frame 100 includes an inner sub-frame 103, a middle sub-frame 102, and an outer sub-frame 101, which are sequentially nested from the inside out. The outer sub-frame 101, middle sub-frame 102, and inner sub-frame 103 are all made of metal springs. The rotating shaft 104 includes a third shaft 1043 disposed between the outer sub-frame 101 and the middle sub-frame 102, which is a hollow body formed by the outer sub-frame 101 and the middle sub-frame 102. The rotating shaft 104 also includes a fourth shaft 1044 disposed between the middle sub-frame 102 and the inner sub-frame 103, with the portion located in the middle sub-frame 102 being a hollow body. The directions of the third shaft 1043 and the fourth shaft 1044 intersect, and the inner sub-frame and / or the middle sub-frame are the target sub-frames. In this embodiment, the frame that resonates can be the inner sub-frame 103, or the middle sub-frame 102, or both the inner sub-frame 103 and the middle sub-frame 102. The third magnet 110 is subjected to a magnetic force, causing the intermediate sub-frame 102 to vibrate around the axis of the third axis 1043. This causes the light reflected by the outer mirror 106 to scan in a direction perpendicular to the axis of the third axis 1043. The fourth magnet 111 is subjected to a magnetic force, causing the inner sub-frame 103 to vibrate along the axis of the fourth axis 1044. This also causes the light reflected by the outer mirror 106 to scan in a direction perpendicular to the axis of the fourth axis 1044. In some embodiments of this application, optionally, the axes of the third axis 1043 and the fourth axis 1044 are perpendicular to each other. In some embodiments of this application, optionally, when both the inner sub-frame 103 and the intermediate sub-frame 102 are target sub-frames, the ratio of their resonant frequencies is an integer. When the ratio of the resonant frequencies of the inner sub-frame 103 and the intermediate sub-frame 102 is an integer ratio, the scanning trajectory of the light reflected by the outer mirror 106 is stable and the scanning line is closed, forming a Lissajous figure.

[0045] In some embodiments of this application, the inner sub-frame 103 may optionally be circular and the outer sub-frame 101 may be square. If an intermediate sub-frame 102 is provided in the embodiment, the shape of the intermediate sub-frame 102 may also be circular, specifically, it may be a circular ring structure, and the fixing frame 108 fixedly connected to the intermediate sub-frame 102 is also a circular ring structure.

[0046] Figure 7 This is a three-dimensional structural schematic diagram of a resonant scanning mirror according to an embodiment of this application. Figure 8 yes Figure 7 An exploded view of the structure shown. Combined with... Figure 7 and Figure 8As shown, the resonant scanning mirror 600 includes at least a light-emitting component, a coil assembly, and a base 601. The light-emitting component and the coil assembly are mounted on a PCB board 602, which is fixed to the base 601. The base has a raised edge 612 for fixing the resonant scanning mirror 600 to an external structure. A mirror rotation assembly is disposed opposite to the PCB board 602. The light-emitting component includes a light source 603 and multiple photocells 604 surrounding the light source 603. The coil assembly includes multiple winding coils 605 surrounding the photocells 604. In some embodiments of this application, optionally, a light shield 613 is provided between the photocells 604 and the winding coils 605 to reduce interference from external light on the photocells 604. In this embodiment, the resonant scanning mirror 600 further includes a reflector mounting frame 100, which is disposed on the opposite side of the photovoltaic cell 604 and fixed to the base 601 by a connector (e.g., bolts). The inner reflector 105 and the light source 603 in the light-emitting assembly are opposite each other. A magnet 107 disposed on the sub-frame of the reflector mounting frame 100 is opposite to the winding coil. The Ampere force generated by the winding coil interacts with the magnet to cause the sub-frame to resonate and form the target sub-frame. Figure 7 and Figure 8 In the resonant scanning galvanometer shown, the mirror mounting frame 100 is... Figure 1 and Figure 2 The mirror mounting frame shown.

[0047] See also Figure 7 and Figure 8 As shown, the resonant scanning galvanometer 600 also includes a washer 607 and a clamping frame 608. The washer 607 is disposed between the mirror mounting frame 100 and the PCB board 602. The clamping frame 608 and the outermost sub-frame of the mirror mounting frame 100 have the same shape. A circular hole 6081 is provided on the clamping frame 608, and a bolt 609 is provided in the circular hole 6081. The bolt 609 passes through the clamping frame 608, the mirror mounting frame 100, the washer 607, the PCB board 602 and the base 601.

[0048] In this embodiment, optionally, to achieve resonance in the target subframe, the frequency of the current flowing through the winding coil corresponding to the target subframe is the same as the natural frequency of the target subframe. For example, in Figure 7 and Figure 8In the illustrated embodiment, for the inner subframe 103 to resonate, the frequency of the current flowing through the first winding coil 6051 needs to be the same as the natural frequency of the inner subframe 103. In some embodiments of this application, optionally, a 200Hz alternating current flows through the first winding coil 6051, and the natural frequency of the metal spring vibrating around the fourth axis 1044 is 200Hz, causing the inner subframe 103 to resonate.

[0049] See also Figure 7 and Figure 8 As shown, the center of the light source 603 coincides with the center of the photovoltaic array and lies in the same plane. Four photovoltaic cells 604, arranged in an array, measure the movement of the light spot reflected by the inner mirror in two orthogonal directions, thereby measuring the mirror deflection angle. The photosensitive surface of the photovoltaic cell 604 receives the light reflected by the inner mirror 105, generating a photoelectric effect inside the cell, responding with a photocurrent proportional to the received light power. When the mirror deflects, the received light power of the photovoltaic cell 604 changes, subsequently changing the photocurrent of the photovoltaic cell 604.

[0050] In this design, light source 603 is approximated as a Lambertian point light source. The photosensitive surfaces of the four photocells 604 are always covered by reflected light spots.

[0051] The working process of the resonant scanning galvanometer is as follows:

[0052] The light source 603 emits light in the 940nm band, which is reflected by the inner reflector 105 and then incident on the photosensitive surface of the four-unit photovoltaic cell 604 (photodetector). When the inner reflector 105 rotates in two dimensions, it can be approximated as rotating around the third and fourth axes, which are perpendicular. The four-unit photovoltaic cell 604 converts the received light energy into four photocurrents. The photocurrents with angle information are collected by the closed-loop servo control system, processed by the normalization and difference ratio algorithm, and then the mechanical drive system is controlled to drive the outer reflector 106 to deflect to the command angle.

[0053] The operating modes of the resonant scanning mirror corresponding to this embodiment include the following three:

[0054] (1) The scanning mode operates in a non-resonant state on both axes. The working bandwidth of the galvanometer in both directions is adjustable from DC drive to a certain frequency, and it does not operate at the resonant frequency (both the internal subframe and the middle subframe vibrate at the non-resonant frequency point, with a frequency of 10-30 Hz). When driven by DC voltage, the light spot reflected by the external mirror can be maintained at a fixed position, thus achieving a point-to-point scanning effect. The scanning pattern in this working mode is as follows: Figure 9 As shown.

[0055] (2) Vibration around the third axis adopts a resonant mode (scan line corresponds to the vertical axis), driven by a sine wave operating at the inherent resonant frequency of the galvanometer, typically several hundred hertz, allowing the reflected beam to scan rapidly in the direction perpendicular to the third axis. Then, vibration around the fourth axis is in a quasi-static mode (scan line corresponds to the horizontal axis), driven by a low-frequency triangular or sawtooth wave, typically tens of hertz. In this operating mode, the middle subframe vibrates at the resonant frequency, while the inner subframe vibrates at the non-resonant frequency. The scanning pattern in this operating mode is as follows: Figure 10 and Figure 11 As shown. Among them, Figure 10 The frequency ratio of the horizontal axis to the vertical axis corresponding to the graph shown is 10:66, and the phase difference is 90°. Figure 11 The horizontal-to-vertical axis frequency ratio shown is 11:155, with a phase difference of 90°.

[0056] (3) Both axes operate in resonant scanning mode. In this mode, both axes operate within their respective narrow frequency ranges and are driven by high-frequency sine waves (both the middle and outer subframes vibrate at the resonant frequency). Because the mirror deformation and scanning angle are significant in resonant mode, the amplitude of the input sine wave is controlled within a certain range to prevent excessive shaft deformation and damage. The scanning effect of the reflected beam in this mode is a Lissajous figure. The Lissajous figure trajectory can be adjusted by changing the ratio and / or phase difference of the operating frequencies (vibration frequencies of the metal springs) of the two axes. The scanning pattern in this operating mode is as follows: Figure 12-13 As shown, where, Figure 12 The frequency ratio of the horizontal axis to the vertical axis of the scan pattern shown is 32:47, with a phase difference of 90°. Figure 13 The frequency ratio of the horizontal axis to the vertical axis of the scan pattern shown is 33:98, and the phase difference is 90°.

[0057] Figure 14 This is a three-dimensional structural schematic diagram of another resonant scanning mirror according to an embodiment of this application. Figure 15 yes Figure 14 Exploded view of the structure shown. Figure 14 and Figure 15 The resonant scanning mirror shown is Figure 7 and Figure 8 The structures of most of the resonant scanning mirrors shown are the same; the differences lie in... Figure 14 and Figure 15 The mirror mounting frame in the illustrated embodiment is Figure 3 and Figure 4 The mirror mounting frame shown, and correspondingly, Figure 14 and Figure 15The number of coils and photocells in the resonant scanning mirror shown can be adaptively reduced. The operating modes of the resonant scanning mirror corresponding to this embodiment include the following two:

[0058] (1) Resonance mode: The internal subframe is driven to vibrate at its inherent resonant frequency point by a sine wave, usually several hundred hertz, so that the reflected beam can scan rapidly along the direction perpendicular to the first axis. The scanning pattern is usually a straight line feature pattern, and the resonant frequency can reach 300 Hz.

[0059] (2) Non-resonant mode: The internal subframe is driven to vibrate at a non-resonant frequency point by a low-frequency triangular wave or sawtooth wave. The frequency is usually tens of hertz, and the scanning pattern is a point feature pattern.

[0060] Figure 16 This is a three-dimensional structural schematic diagram of another resonant scanning mirror according to an embodiment of this application. Figure 17 yes Figure 16 Exploded view of the structure shown. Figure 16 and Figure 17 The resonant scanning mirror shown is Figure 7 and Figure 8 The structures of most of the resonant scanning mirrors shown are the same; the differences lie in... Figure 16 and Figure 17 The mirror mounting frame in the illustrated embodiment is Figure 4 and Figure 5 The mirror mounting frame shown is further illustrated in this embodiment, where the outer sub-frame of the mirror mounting frame also serves as the clamping frame for the resonant scanning galvanometer. The operating modes of the resonant scanning galvanometer corresponding to this embodiment include the following two:

[0061] (1) The vibration frequency of the subframe corresponding to the X-axis (horizontal axis) of the two axes (the light reflected by the external mirror moves along two axes, which are in the same direction as the rotation axis of the mirror mounting frame; if the light moves along the X-axis, the axis around which the mirror vibrates is perpendicular to the X-axis; if the light moves along the Y-axis, the axis around which the mirror vibrates is perpendicular to the Y-axis; where the X-axis and Y-axis are perpendicular, the two axes refer to the X-axis and Y-axis) is 10-30 Hz, operating in quasi-static mode; the Y-axis (vertical axis) operates at a non-resonant frequency, for example, 10-30 Hz. Through the control system, the scanning is a point-to-point vector graphic, for example... Figure 9 The diagram shows that the operating bandwidth in both directions is adjustable from DC drive to a certain frequency, and it does not operate at the resonant frequency. When driven by DC voltage, the light spot reflected by the mirror can be maintained in a fixed position, thus achieving a point-to-point scanning effect.

[0062] (2) The Y-axis (vertical axis) adopts a resonant mode, using a sine wave to drive the internal sub-frame at its inherent resonant frequency, typically several hundred hertz, allowing the beam reflected by the mirror to scan rapidly along the axis perpendicular to the second axis 1042. Then, the X-axis is in quasi-static mode, using a low-frequency triangular wave or sawtooth wave to drive the intermediate sub-frame to vibrate, typically at a frequency of tens of hertz, allowing the beam reflected by the mirror to scan along the axis perpendicular to the pin 109. The scanning pattern is as follows: Figure 10 and Figure 11 As shown.

[0063] In summary, when both axes are in quasi-static scanning mode, the operating bandwidth of the resonant scanning mirror in both directions is adjustable from DC drive to a certain frequency, and it does not operate at the resonant frequency. When driven by DC voltage, the emitted light spot can be maintained at a fixed position, thus achieving a point-to-point scanning effect, and the scanned image can be obtained as shown in the diagram. Figure 9 The graph shown illustrates this. When the X-axis is in resonant mode, driven by a sine wave at the inherent resonant frequency of the resonant scanning mirror, typically several hundred hertz, the reflected beam scans rapidly in the horizontal direction. Then, in the Y-axis, i.e., quasi-static mode, a low-frequency triangular or sawtooth wave is used for scanning, typically at tens of Hz, resulting in a scan as shown. Figure 10 or Figure 11 The graphic shown has a relatively large coverage area. Figure 9 Larger, and combined Figures 10-11 As shown in the scanning patterns, when one axis is in non-resonant (or quasi-static) mode and the other in resonant mode, the higher the frequency of the resonant axis, the denser the lines in the corresponding scanning pattern, and the higher the coverage of the scanning lines. When both the X and Y axes are in resonant scanning mode, both axes operate within their respective narrow frequency ranges and are driven by high-frequency sine waves. Because the deformation and scanning angle of the resonant scanning galvanometer are very significant when operating in resonant mode, careful control of the amplitude of the input sine wave is crucial. Exceeding a certain range may cause the resonant scanning galvanometer to deform due to the shape of the galvanometer support beam (e.g., ...). Figure 1 The third axis (1043) became too large and was damaged. In this mode, the scanning effect of the reflected beam is a Lissajous figure, such as... Figure 12 or Figure 13 As shown, and through comparison Figure 12 and Figure 13 It is known that, with the frequency on the same axis remaining constant, a higher frequency on the other axis results in a denser pattern and greater scan line coverage. Therefore, the Lissajous figure trajectory can be adjusted by the ratio of the operating frequencies of the X and Y axes.

[0064] In other words, when both axes of a resonant scanning galvanometer adopt a resonant scanning mode, the scanning trajectory line in the scanning pattern can cover almost the entire area within the scanning pattern range. Therefore, resonant scanning galvanometers are mainly used in fields such as image-based laser scanning and laser imaging under this working mode, and have higher precision.

[0065] Furthermore, the mirror mounting frame of the resonant scanning galvanometer proposed in this application embodiment has a metal spring capable of resonance, thereby enabling the vibration of the resonant scanning galvanometer in at least one scanning direction to be in a resonant mode, which in turn can improve the scanning angle range of the resonant scanning galvanometer.

[0066] The above embodiments are for illustrative purposes only and are not intended to limit the scope of this application. Those skilled in the art can make various changes and modifications without departing from the scope of this application. Therefore, all equivalent technical solutions should also fall within the scope of this application.

Claims

1. A mirror mounting frame for a resonant scanning galvanometer, comprising a plurality of sub-frames nested sequentially from the inside out, wherein the sub-frames are rotatably connected by a pivot, wherein, The innermost sub-frame has a first side and a second side facing away from each other. The first side is provided with an inner reflector for reflecting light from the inside of the scanning galvanometer, and the second side is provided with an outer reflector for reflecting light from the outside of the scanning galvanometer. The reflector mounting frame is characterized in that at least two adjacent sub-frames are made of metal springs, and the pivot between two adjacent sub-frames made of metal springs is integrally formed with the metal springs. The first side is provided with a magnet, and the sub-frame made of metal springs that resonates under the action of a preset magnetic field force is the target sub-frame.

2. The mirror mounting frame for the scanning galvanometer according to claim 1, characterized in that, The reflector mounting frame includes an inner subframe and an outer subframe. The inner subframe is the innermost subframe. Both the inner and outer subframes are made of metal springs. The pivot is a first shaft, which is a cantilever torsion beam. The portion of the first shaft located in the outer subframe is hollow. The inner subframe is the target subframe.

3. The mirror mounting frame for the scanning galvanometer according to claim 1, characterized in that, The reflector mounting frame includes an inner sub-frame, a middle sub-frame, and an outer sub-frame nested sequentially from the inside out. The inner sub-frame and the middle sub-frame are made of metal springs. The rotating shaft includes a second shaft located between the middle sub-frame and the inner sub-frame. The portion of the second shaft located in the middle sub-frame is hollow. A fixing frame is provided on the outer circumference of the hollow. The rotating shaft also includes a pin disposed between the fixing frame and the outer sub-frame. The fixing frame drives the middle sub-frame to rotate around the pin. The direction of the pin intersects with that of the second shaft. The inner sub-frame is the target sub-frame.

4. The mirror mounting frame for the scanning galvanometer according to claim 1, characterized in that, The mirror mounting frame includes an inner sub-frame, a middle sub-frame, and an outer sub-frame nested sequentially from the inside out. All three sub-frames are made of metal springs. The pivot includes a third axis disposed between the outer and middle sub-frames, which is a hollow structure formed by the outer and middle sub-frames. The pivot also includes a fourth axis disposed between the middle and inner sub-frames, with the portion located in the middle sub-frame being a hollow structure. The third and fourth axes intersect in direction, and the inner and / or middle sub-frames are the target sub-frames.

5. The mirror mounting frame for the scanning galvanometer according to claim 4, characterized in that, When both the inner subframe and the intermediate subframe are target subframes, the ratio of their resonant frequencies is an integer.

6. The mirror mounting frame for the scanning galvanometer according to any one of claims 2-4, characterized in that, The inner sub-frame is circular, and the outer sub-frame is square.

7. The mirror mounting frame for the scanning galvanometer according to claim 3, characterized in that, Both the intermediate sub-frame and the fixed frame are circular ring structures.

8. The mirror mounting frame for the scanning galvanometer according to claim 1, characterized in that, A mounting hole is provided in the middle of the innermost sub-frame, and the inner reflector is disposed in the mounting hole.

9. A resonant scanning mirror, comprising at least a light-emitting component, a coil assembly, and a base, wherein, The light-emitting component and the coil assembly are mounted on a PCB board, which is fixed to a base. The mirror rotation assembly is disposed opposite to the PCB board. The light-emitting component includes a light source and a plurality of photocells surrounding the light source. The coil assembly includes a plurality of winding coils surrounding the photocells. The resonant scanning mirror further includes a mirror mounting frame as described in any one of claims 1-8. The mirror mounting frame is disposed on the opposite side of the photocells and fixed to the base by connectors. The inner mirror is opposite to the light source in the light-emitting component. A magnet disposed on a sub-frame of the mirror mounting frame is opposite to the winding coils. The Ampere force generated by the winding coils acts on the magnets to cause the sub-frames to resonate and form a target sub-frame.

10. The resonant scanning mirror according to claim 9, characterized in that, It also includes a washer and a clamping frame. The washer is disposed between the reflector mounting frame and the PCB board. The clamping frame and the outermost sub-frame of the reflector mounting frame have the same shape. The clamping frame has a circular hole, and a bolt is disposed in the circular hole. The bolt passes through the clamping frame, the reflector mounting frame, the washer, the PCB board and the base.

11. The resonant scanning mirror according to claim 9, characterized in that, The frequency of the current flowing through the winding coil is the same as the natural frequency of the target subframe.

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