A scanning galvanometer driving device with large light window angle and large torsion angle

Abstract

The present application relates to the technical fields of electromagnetic scanning galvanometer, and particularly relates to a scanning galvanometer driving device with large light window angle and large torsion angle, which comprises a galvanometer chip structure and two magnet group structures, the magnet group structure comprises a lower magnet and an upper magnet, the magnetization direction of the lower magnet of one magnet group structure is vertically upward, and the magnetization direction of the upper magnet is horizontally right, the magnetization direction of the lower magnet of the other magnet group structure is vertically downward, and the magnetization direction of the upper magnet is horizontally left, the galvanometer chip structure comprises a fixed base, a movable frame, a reflecting mirror surface, an outer torsion shaft and an inner torsion shaft, the movable frame is connected with the fixed base through the outer torsion shaft, and the reflecting mirror surface is connected with the movable frame through the inner torsion shaft, through the setting of the above structure, the problem that for the electromagnetic scanning galvanometer, the magnetic driving structure requires both strong magnetic field intensity and large magnetic field space distribution range to realize large torsion angle and maintain large light window angle is solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electromagnetic scanning galvanometer, and particularly relates to a scanning galvanometer driving device with large light window angle and large torsion angle. BACKGROUND

[0002] The electromagnetic scanning galvanometer is a MEMS mirror using magnetic actuation method. The mirror drives the reciprocating deflection through the torsion beam under the driving of electromagnetic force, so as to change the direction of reflected light to realize scanning. The torsion angle of the galvanometer is related to the size of the electromagnetic driving force. According to the Lorentz principle, the driving force is determined by the coil current and the magnetic induction intensity across the coil. The scanning galvanometer is a core device in the laser radar, and is mainly used for controlling the emission angle of the laser beam. There are two key parameters of the electromagnetic galvanometer applied in the laser radar, one is the torsion angle, and the other is the light window angle, as shown in FIG. 1. In FIG. 1(a), the scanning mirror rotates from the solid line position to the dotted line position, and the rotation angle α between them is the torsion angle, which determines the detectable angle of a group of laser transceiver modules; in FIG. 1(b), the light window angle β is the included angle of the light which can be incident on the scanning mirror surface without being blocked by the shell structure around the scanning mirror and can be reflected without obstacles. When multiple groups of laser transceiver modules share one scanning galvanometer, the light window angle β determines the overall detectable angle of the multiple groups of laser transceiver modules.

[0003] The effective magnetic field generated by the magnet device should be perpendicular to the direction of the current in the coil and the required driving force. FIG. 2 is two common electromagnetic galvanometer driving devices. In FIG. 2(a), the galvanometer is generally placed at the middle height of the magnet, and the magnetic field around the coil is the approximate horizontal effective driving magnetic field. However, in order to enhance the magnetic field strength and increase the spatial distribution range of the magnetic field, it is necessary to increase the width and height of the magnet, so the product is relatively bulky and the light window angle is limited. In FIG. 2(b), the magnet group provides a driving magnetic field for the galvanometer coil in the middle gap by repelling the upper and lower poles, so the effective magnetic field is only distributed in the gap region between the upper and lower magnets, the spatial distribution range is small, and the upper and lower magnets must be very close to ensure a strong magnetic field strength, which not only limits the torsion angle of the galvanometer, but also increases the assembly difficulty.

[0004] Patent CN104570332B discloses a magnetic field system of a MEMS scanning galvanometer, that is, the magnet group shown in FIG. 2(b), which is composed of two groups of upper magnets and lower magnets located on the upper and lower sides of the galvanometer. However, since the upper and lower magnets are vertically magnetized and have the same magnetic properties on the opposite surfaces, although a larger magnetic induction intensity is obtained in the driving plane of the galvanometer, the smaller the gap between the upper and lower magnets, the higher the assembly difficulty, and the galvanometer driving coil can only obtain a larger magnetic induction intensity in the gap between the upper and lower magnets, so the torsion angle is limited; in addition, the light window angle is also limited by the shape and size of the upper magnet.

[0005] Patent CN102763176B discloses a magnetic actuation system by a magnet and a magnetic guide material, the magnet group includes two vertically magnetized magnets with opposite magnetization directions. This structure needs to guide the driving magnetic field to the galvanometer driving plane through the magnetic guide material as a field focusing plate, the assembly structure is relatively complex, and the spatial distribution range of the magnetic field is small, which is difficult to provide a large driving magnetic field required by a large mirror and a large torsion angle. SUMMARY

[0006] The purpose of the present application is to provide a scanning galvanometer driving device with a large light window angle and a large torsion angle, which solves the problem of requiring both strong magnetic field strength and large magnetic field spatial distribution range for the electromagnetic scanning galvanometer to achieve a large torsion angle while maintaining a large light window angle.

[0007] To achieve the above purpose, the present application provides a scanning galvanometer driving device with a large light window angle and a large torsion angle, which includes a galvanometer chip structure and two magnet group structures, the galvanometer chip structure is arranged between the two magnet group structures, the magnet group structure includes a lower magnet and an upper magnet, the magnetization direction of the lower magnet of one magnet group structure is vertically upward, and the magnetization direction of the upper magnet is horizontally right, the magnetization direction of the lower magnet of the other magnet group structure is vertically downward, and the magnetization direction of the upper magnet is horizontally left, the upper and lower gap of the upper magnet and the lower magnet of any magnet group structure is less than 6mm.

[0008] The galvanometer chip structure includes a fixed base, a movable frame, a reflecting mirror, an outer torsion shaft and an inner torsion shaft, the movable frame is connected with the fixed base through the outer torsion shaft, and the reflecting mirror is connected with the movable frame through the inner torsion shaft.

[0009] Among them, the scanning galvanometer driving device with a large light window angle and a large torsion angle further includes a shell structure, the shell structure includes an upper frame, a lower frame, a base and a cross fixing piece, the lower frame is fixedly connected with the base, the upper frame is fixedly connected with the lower frame, the upper frame is located on the side of the lower frame away from the base, and the cross fixing piece is arranged below the galvanometer chip structure.

[0010] Among them, the lower magnet of the two magnet group structures is a pair of first and second stepped L-shaped magnets magnetized upward and downward, and the two upper magnets of the two magnet group structures are a pair of first and second wedge-shaped upper magnets magnetized horizontally, the first and second stepped L-shaped magnets each include an L-shaped magnet magnetized in the height direction and a rectangular magnet, and the rectangular magnet is arranged on the inner side of the L-shaped magnet.

[0011] The upper magnets of the two magnet group structures include a first wedge-shaped upper magnet and a second wedge-shaped upper magnet with opposite wedge-shaped pole faces, and the lower magnets of the two magnet group structures include a first L-shaped magnet and a second L-shaped magnet with opposite upper surface poles.

[0012] The upper magnets of the two magnet group structures include a first wedge-shaped upper magnet, a second wedge-shaped upper magnet, a third wedge-shaped upper magnet and a fourth wedge-shaped upper magnet, and the lower magnets of the two magnet group structures include a first ladder-shaped L-shaped magnet and a second ladder-shaped L-shaped magnet.

[0013] The upper magnets of the two magnet group structures are a pair of horizontally magnetized first wedge-shaped upper magnets and second wedge-shaped upper magnets, and the lower magnets of the two magnet group structures are a pair of vertically magnetized first rectangular magnets and second rectangular magnets.

[0014] The scanning galvanometer driving device with large light window angle and large torsion angle of the application comprises a galvanometer chip structure and two magnet group structures, the magnet group structure comprises a lower magnet and an upper magnet, the magnetization direction of the lower magnet of one magnet group structure is vertically upward, and the magnetization direction of the upper magnet is horizontally right, the magnetization direction of the lower magnet of the other magnet group structure is vertically downward, and the magnetization direction of the upper magnet is horizontally left, the galvanometer chip structure comprises a fixed base, a movable frame, a reflecting mirror surface, an outer torsion shaft and an inner torsion shaft, the movable frame is connected with the fixed base through the outer torsion shaft, the reflecting mirror surface is connected with the movable frame through the inner torsion shaft, through the setting of the above structure, the problem that for the electromagnetic scanning galvanometer, the magnetic driving structure requires both strong magnetic field intensity and large magnetic field space distribution range to realize large torsion angle and maintain large light window angle is solved. BRIEF DESCRIPTION OF DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or prior art description will be briefly introduced below.

[0016] Fig. 1(a) is a schematic diagram of the torsion angle a of the electromagnetic scanning galvanometer applied in the laser radar of the prior art, and Fig. 1(b) is a schematic diagram of the light window angle β of the electromagnetic scanning galvanometer applied in the laser radar of the prior art.

[0017] Fig. 2(a) and Fig. 2(b) are two kinds of electromagnetic scanning galvanometer driving devices in the prior art.

[0018] Figure 3 Fig. 3 is a schematic diagram of the galvanometer chip structure of the scanning galvanometer driving device with large light window angle and large torsion angle of the application.

[0019] Figure 4FIG. 1 is a schematic diagram of a driving magnetic field of an embodiment 1 of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0020] Figure 5 FIG. 2 is a schematic diagram of a scanning galvanometer driving device according to the present application. Figure 4 FIG. 3 is a sectional view along the direction of AA' of FIG. 2.

[0021] Figure 6 FIG. 4 is a schematic diagram of a first stepped L-shaped magnet of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0022] Figure 7 FIG. 5 is a schematic diagram of a first wedge-shaped upper magnet of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0023] FIG. 8(a), FIG. 8(b), and FIG. 8(c) are a housing structure diagram, an exploded view, and a structure diagram of a lower magnet, respectively, of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0024] Figure 9 FIG. 9 is a schematic diagram of an embodiment 2 of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0025] Figure 10 FIG. 10 is a schematic diagram of an embodiment 3 of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0026] Figure 11 FIG. 11 is a schematic diagram of an embodiment 4 of a scanning galvanometer driving device with a large light window angle and a large torsion angle according to the present application.

[0027] Figure 12 FIG. 12 is a schematic diagram of a one-dimensional galvanometer in the embodiment 4 according to the present application.

[0028] 30 - fixed base, 31 - movable frame, 32 - mirror surface, 33 - outer torsion shaft, 34 - inner torsion shaft, 51 - upper frame, 52 - lower frame, 53 - base, 54 - cross fixing member;

[0029] First embodiment: 41 - first wedge-shaped upper magnet, 42 - second wedge-shaped upper magnet, 43 - first stepped L-shaped magnet, 44 - second stepped L-shaped magnet, 431 - L-shaped magnet, 432 - rectangular magnet;

[0030] Second embodiment: 41 - first wedge-shaped upper magnet, 42 - second wedge-shaped upper magnet, 433 - first L-shaped magnet, 443 - second L-shaped magnet;

[0031] Third embodiment: 411-first wedge-shaped upper magnet, 421-second wedge-shaped upper magnet, 412-third wedge-shaped upper magnet, 422-fourth wedge-shaped upper magnet, 43-first ladder-shaped L-shaped magnet, 44-second ladder-shaped L-shaped magnet;

[0032] Fourth embodiment: 41-first wedge-shaped upper magnet, 42-second wedge-shaped upper magnet, 434-first rectangular magnet, 444-second rectangular magnet, 60-fixed base, 61-movable frame, 63-torsion shaft, 62-mirror surface. DETAILED DESCRIPTION

[0033] The embodiments of the present application are described in detail below, examples of which are shown in the accompanying drawings, the embodiments described below by referring to the accompanying drawings are exemplary, and are intended to explain the present application, and cannot be understood as a limitation of the present application.

[0034] The present application provides a large light window angle and large torsion angle scanning galvanometer driving device, comprising a galvanometer chip structure and two magnet group structures, the galvanometer chip structure is arranged between the two magnet group structures, the magnet group structure comprises a lower magnet and an upper magnet, the magnetization direction of the lower magnet of one magnet group structure is vertically upward, and the magnetization direction of the upper magnet is horizontally right, the magnetization direction of the lower magnet of the other magnet group structure is vertically downward, and the magnetization direction of the upper magnet is horizontally left, the upper and lower gap of the upper magnet and the lower magnet of any magnet group structure is less than 6mm; the galvanometer chip structure comprises a fixed base 30, a movable frame 31, a mirror surface 32, an outer torsion shaft 33 and an inner torsion shaft 34, the movable frame 31 is connected with the fixed base 30 through the outer torsion shaft 33, and the mirror surface 32 is connected with the movable frame 31 through the inner torsion shaft 34. The large light window angle and large torsion angle scanning galvanometer driving device further comprises a shell structure, the shell structure comprises an upper frame 51, a lower frame 52, a base 53 and a cross fixing piece 54, the lower frame 52 is fixedly connected with the base 53, the upper frame 51 is fixedly connected with the lower frame 52, the upper frame 51 is located on the side of the lower frame 52 away from the base 53, and the cross fixing piece 54 is arranged below the galvanometer chip structure.

[0035] The movable frame 31 can be a rectangular outer frame structure as shown in FIG. 1, or a square outer frame, a circular outer frame, an oval outer frame or other structures. Figure 3 The outer torsion shaft 33 can be a straight beam structure as shown in FIG. 1, or a ring beam, a folded beam or other beam structures. Figure 3 The mirror surface 32 is formed by evaporating or sputtering a metal reflecting layer on the surface of a silicon material, and its shape can be a square as shown in FIG. 1, a circle, an ellipse or other shapes. Figure 3The elliptical structure shown in the figure can also be circular, square, rectangular, polygonal, or other structures. The reflecting surface 32 is connected to the movable frame 31 through the inner torsion shaft 34, which can be a Figure 3 The straight beam structure shown in the figure can also be a ring beam, a folded beam, or other beam structures. The movable frame 31 is provided with multiple turns of metal wires. The magnetic driving device generates magnetic fields B1 in the AA' direction and B2 in the BB' direction on the movable frame 31, respectively. Figure 3 The metal wires in the driving magnetic field generate Lorentz force after being energized. Under the action of the Lorentz force, the reflecting surface 32 will rotate around the AA' axis through the inner torsion shaft 34, and the movable frame 31 and the reflecting surface 32 will rotate together around the BB' axis through the outer torsion shaft 33, finally realizing the biaxial scanning of the reflecting surface 32.

[0036] Embodiment 1:

[0037] Please refer to Figure 4 to Figure 8, Figure 4 is a schematic diagram of the driving magnetic field of embodiment 1 of the scanning galvanometer driving device with large light window angle and large torsion angle of the application, Figure 5 is a schematic diagram of the first stepped L-shaped magnet of the scanning galvanometer driving device with large light window angle and large torsion angle of the application, Figure 4 is a sectional view along the AA' direction in the figure, Figure 6 is a schematic diagram of the first stepped L-shaped magnet of the scanning galvanometer driving device with large light window angle and large torsion angle of the application, Figure 7 is a schematic diagram of the first stepped L-shaped magnet of the scanning galvanometer driving device with large light window angle and large torsion angle of the application, Figure 4 The driving magnetic field is provided by the magnet group structure as shown in the figure. The magnet group structure is composed of a pair of first and second stepped L-shaped magnets 43 and 44 magnetized upward and downward, and a pair of first and second wedge-shaped upper magnets 41 and 42 magnetized horizontally. The first and second stepped L-shaped magnets 43 and 44 are located below the galvanometer chip structure, and the first and second wedge-shaped upper magnets 41 and 42 are located above the galvanometer chip structure. The gap between the upper and lower magnets is not more than 6mm. This magnet group structure can generate two mutually perpendicular magnetic fields in the AA' and BB' directions as shown in the figure. Figure 4 The galvanometer is a two-dimensional scanning galvanometer, and a larger deflection angle requires a larger movement space for the driving coil. This magnet group structure can provide a stronger magnetic field strength in a larger movement space range, and the effective magnetic field strength in the entire movement space range is not less than 200mT.

[0038] Figure 4 The cross section of the middle magnet group structure along AA' direction is shown in Figure 5 Under the joint action of the upper and lower magnet coupling magnetic field, the movable frame 31 has a larger effective driving magnetic field strength and a larger spatial distribution range at the position.

[0039] The lower magnet structure is shown in the attached Figure 6 The L-shaped magnet 431 with a height of H and the rectangular magnet 432 with a height of h are combined, and the magnetization directions of the two are the same, that is, they are magnetized along the height direction. Generally, H>h. In the magnet group structure, the first and second stepped L-shaped magnets 43 and 44 have the same geometry but opposite magnetization directions, and are placed symmetrically. This magnet combination can effectively increase the magnetic field strength and the spatial distribution range of the magnetic field.

[0040] The upper magnet is a wedge-shaped structure, and its cross section is shown in the attached Figure 7 The wedge-shaped surfaces are located on both sides of the frame edge, and the included angle θ is less than 60°. The polarity of the wedge-shaped surface is the same as that of the upper surface of the magnet below, so the horizontal driving magnetic field can be significantly enhanced. In addition, Figure 4 Since there is no magnet structure above the BB' direction and the upper magnet has a large wedge-shaped surface with a large inclination angle in the AA' direction, the galvanometer can meet the requirement of a large light window angle.

[0041] The shell structure and explosion diagram of the scanning galvanometer are shown in Figs. 8(a) and (b). The upper frame 51 is made of a non-magnetic material, which is used to fix the first and second wedge-shaped upper magnets 41 and 42 while meeting the requirement of a large light window angle. The lower frame 52 is made of a non-magnetic material, and the base 53 is made of a magnetic material, which is conducive to enhancing the magnetic field. The position of the lower magnet is shown in Fig. 8(c). The first and second stepped L-shaped magnets 43 and 44 are fixed and positioned by the cross fixing member 54, which is made of a non-magnetic material. The lower frame 52 fixes the first and second stepped L-shaped magnets 43 and 44 on one hand, and the groove structure on its upper surface can directly fix the galvanometer chip on the other hand. The cross fixing member 54 can prevent the rectangular magnet 432 of the first and second stepped L-shaped magnets 43 and 44 from falling off.

[0042] Example 2

[0043] Please refer to Figure 9 , Figure 9Figure 2 is a schematic diagram of embodiment 2 of the application, which is a scanning galvanometer driving device with a large aperture angle and a large torsion angle. The first L-shaped magnet 433 and the second L-shaped magnet 443 are L-shaped magnets with opposite magnetic poles on their upper surfaces. The first wedge-shaped upper magnet 41 has the same magnetic pole on its wedge-shaped surface as the upper surface of the first L-shaped magnet 433, and the second wedge-shaped upper magnet 42 has the same magnetic pole on its wedge-shaped surface as the upper surface of the second L-shaped magnet 443. The magnet group structure generates a strong driving magnetic field in the movement space of the movable frame 31. Compared with embodiment 1, the lower magnet does not include the rectangular magnet 432 in embodiment 1, but the driving magnet group with the L-shaped lower magnet magnetized in the up-down direction and the wedge-shaped upper magnet magnetized in the horizontal direction is still within the protection scope.

[0044] Embodiment 3

[0045] Figure 3 is a schematic diagram of embodiment 3 of the application, which is a scanning galvanometer driving device with a large aperture angle and a large torsion angle. Figure 10 Figure 3 is a schematic diagram of embodiment 3 of the application, which is a scanning galvanometer driving device with a large aperture angle and a large torsion angle.

[0046] Embodiment 4

[0047] Figure 4 is a schematic diagram of embodiment 4 of the application, which is a scanning galvanometer driving device with a large aperture angle and a large torsion angle. Figure 11 and Figure 12 , Figure 11 Figure 4 is a schematic diagram of embodiment 4 of the application, which is a scanning galvanometer driving device with a large aperture angle and a large torsion angle. Figure 12 Figure 5 is a schematic diagram of a one-dimensional galvanometer in embodiment 4 of the application. The wedge-shaped surfaces of the first wedge-shaped upper magnet 41 and the second wedge-shaped upper magnet 42 have opposite magnetic poles, and this embodiment is a driving magnet group structure for driving a one-dimensional large-angle galvanometer. The first wedge-shaped upper magnet 41 and the second wedge-shaped upper magnet 42 are horizontally magnetized upper magnets, but the first rectangular lower magnet 434 and the second rectangular magnet 444 are rectangular magnets magnetized in the up-down direction.

[0048] Figure 12 is Figure 11 A schematic diagram of a one-dimensional galvanometer in the prior art, including the fixed base 60, the movable frame 61, the torsion shaft 63 and the mirror surface 62. The movable frame 61 is connected to the fixed base 60 through the torsion shaft 63. The torsion shaft 63 can be a straight beam structure as shown in the prior art, or a ring beam, a folded beam or other beam structures. The mirror surface 62 is formed by evaporating or sputtering a metal reflecting layer on the surface of a silicon material, and its shape can be an elliptical structure as shown in the prior art, or a circular, square, rectangular, polygonal or other structure. The mirror surface 62 is directly connected to the movable frame 61. The movable frame 61 is provided with multiple turns of metal wires. The magnetic driving device generates a magnetic field B1 perpendicular to the AA' direction as shown on the frame. The metal wires in the driving magnetic field will generate a Lorentz force after being electrified. Under the action of the Lorentz force, the movable frame 61 and the mirror surface 62 will rotate together around the AA' axis through the torsion shaft 63, and finally realize the single-axis scanning of the mirror surface 62. Figure 12 Figure 12 Figure 12

[0049] The scanning galvanometer driving device of the present application relates to a scanning galvanometer driving device containing two magnet groups, each of which contains a lower magnet and an upper magnet. The magnetization direction of the lower magnet in at least one magnet group is vertically upward, and the magnetization direction of the upper magnet in the magnet group is horizontally right; the magnetization direction of the lower magnet in at least one magnet group is vertically downward, and the magnetization direction of the upper magnet in the magnet group is horizontally left. The gap between the upper and lower magnets is not more than 6 mm, which can provide two mutually perpendicular horizontal direction driving magnetic fields for the scanning galvanometer, and provides a strong magnetic field strength in a larger movement space, which is conducive to driving the scanning galvanometer to realize large-angle deflection.

[0050] The lower magnet is formed by combining an L-shaped magnet with a height of H and a rectangular magnet with a height of h (H>h), both of which are magnetized along the height direction and have the same magnetization direction. The rectangular magnet is parallel to the frame edge, and its magnetic surface is located directly below the coil. This magnet design can effectively increase the magnetic field strength and the spatial distribution range of the magnetic field.

[0051] The upper magnet is wedge-shaped and magnetized in the horizontal direction. Compared with the structure without an upper magnet, it provides a stronger effective horizontal magnetic field for large-angle deflection of the galvanometer; compared with the rectangular upper magnet structure, it can provide a larger light window angle; compared with the vertically magnetized upper magnet structure, it reduces the assembly difficulty.

[0052] ​​​The above disclosure only shows one or more preferred embodiments of the present application, and cannot limit the scope of the present application. Those skilled in the art can understand that the implementation of all or part of the above processes, and the equivalent changes made according to the claims of the present application, still belong to the scope covered by the present application.

Claims

1.A scanning galvanometer driving device with large aperture angle and large torsion angle, comprising a galvanometer chip structure and two magnet group structures, the galvanometer chip structure is arranged between the two magnet group structures, each magnet group structure comprises a lower magnet and an upper magnet, the magnetization direction of the lower magnet of one magnet group structure is vertically upward, and the magnetization direction of the upper magnet is horizontally right, the magnetization direction of the lower magnet of the other magnet group structure is vertically downward, and the magnetization direction of the upper magnet is horizontally left, the gap between the upper magnet and the lower magnet of any magnet group structure is less than 6mm. The galvanometer chip structure comprises a fixed base, a movable frame, a mirror surface, an outer torsion shaft and an inner torsion shaft, the movable frame is connected with the fixed base through the outer torsion shaft, and the mirror surface is connected with the movable frame through the inner torsion shaft. 2.The scanning galvanometer driving device with large aperture angle and large torsion angle according to claim 1, further comprising a housing structure, the housing structure comprises an upper frame, a lower frame, a base and a cross fixing piece, the lower frame is fixedly connected with the base, the upper frame is fixedly connected with the lower frame, the upper frame is located on the side of the lower frame away from the base, and the cross fixing piece is arranged below the galvanometer chip structure. 3.The scanning galvanometer driving device with large aperture angle and large torsion angle according to claim 2, wherein the lower magnet of each magnet group structure is a pair of first and second stepped L-shaped magnets with opposite magnetization directions, and the upper magnet of each magnet group structure is a pair of first and second wedge-shaped upper magnets with opposite magnetization directions, the first and second stepped L-shaped magnets each comprise an L-shaped magnet and a rectangular magnet, and the rectangular magnet is arranged on the inner side of the L-shaped magnet. 4.The scanning galvanometer driving device with large aperture angle and large torsion angle according to claim 2, wherein the upper magnet of each magnet group structure comprises a first wedge-shaped upper magnet and a second wedge-shaped upper magnet with opposite wedge-shaped faces, and the lower magnet of each magnet group structure comprises a first L-shaped magnet and a second L-shaped magnet with opposite upper surfaces. 5.The scanning galvanometer driving device with large aperture angle and large torsion angle according to claim 2, wherein the upper magnet of each magnet group structure comprises a first wedge-shaped upper magnet, a second wedge-shaped upper magnet, a third wedge-shaped upper magnet and a fourth wedge-shaped upper magnet, and the lower magnet of each magnet group structure comprises a first stepped L-shaped magnet and a second stepped L-shaped magnet. 6.The scanning galvanometer driving device with large aperture angle and large torsion angle according to claim 5, wherein ​ ​ ​ ​ ​ The upper magnets of the two magnet group structures are a pair of horizontally magnetized first and second wedge-shaped upper magnets, and the lower magnets of the two magnet group structures are a pair of vertically magnetized first and second rectangular magnets.

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