Camera focusing mechanism based on ultrasonic micro-motor structure and module

Abstract

The invention discloses a camera focusing mechanism and module based on an ultrasonic micro-motor structure, and belongs to the field of camera focusing mechanism design, and the camera focusing mechanism comprises an ultrasonic micro-motor driven by a piezoelectric film, an inclined plane driven structure, a spring structure, and a housing provided with a notch structure and a housing projection structure. When the stator structure of the ultrasonic micro motor is excited and driven by an external signal to generate a standing wave or a traveling wave, the stator bulge structure does elliptic motion, and the elliptic motion pushes the friction layer, the magnetic material layer and the inclined plane driving structure in the rotor structure to do rotary motion; in the rotating process, the limiting column is matched with the notch structure, the degree of freedom in the rotating direction is restrained, the inclined face is driven by the driving structure to do linear motion in the optical axis direction, and the shell protruding structure and the outer edge of the rotor structure are used for achieving the limiting effect in the plane direction. According to the invention, higher adjustment precision and higher response speed can be realized, and the method is more beneficial to being embedded into a camera module structure applied to a mobile phone and other terminals.

Description

Technical Field

[0001] The present invention relates to the field of camera focusing mechanism design, and more specifically, to a camera focusing mechanism and module based on an ultrasonic micromotor structure. Background Art

[0002] The camera modules currently used in mobile phones, tablets, and other terminals are primarily driven by voice coil motors (VCMs). These use electromagnetic force to drive the lens, changing the distance between the lens and the sensor to achieve autofocus (AF). VCMs have a relatively simple structure and mature manufacturing processes, and are currently in large-scale mass production. Another form of technology is shape memory alloy (SMA), a newer lens focusing technology that uses the deformation properties of shape memory alloys under temperature changes to achieve lens movement. By utilizing the optical properties (such as refractive index) and deformability of liquids (or soft polymers), the shape or position of the liquid (polymer) can be changed through external control (such as electric fields, magnetic fields, pressure, or temperature), thereby adjusting the optical path and focal length.

[0003] Solutions using memory alloy wire heating or electromagnetic motor drive have the following problems: the focusing mechanism is complex, bulky, noisy, requires high drive voltage, and has a bulky drive circuit, making it difficult to embed in camera modules for mobile phones and other terminal applications. Furthermore, the adjustment accuracy is low and the response speed is slow. Summary of the Invention

[0004] The purpose of the present invention is to overcome the shortcomings of the existing technology and provide a camera focusing mechanism and module based on an ultrasonic micromotor structure, which can achieve higher adjustment accuracy and faster response speed, and is more conducive to being embedded in the camera module structure of terminal applications such as mobile phones.

[0005] The object of the present invention is achieved through the following solutions:

[0006] A camera focusing mechanism based on an ultrasonic micromotor structure, comprising:

[0007] The piezoelectric film-driven ultrasonic micromotor has a rotor structure with an inclined drive structure, a magnetic material layer, and a friction layer. The inclined drive structure is fixedly connected to the magnetic material layer and the friction layer. The magnetic material layer provides a rotating magnetic field when the rotor structure rotates. The stator structure has a stator protrusion structure. The stator protrusion structure contacts the friction layer and drives the rotor structure to rotate through friction.

[0008] The inclined plane driven structure is integrally fixedly connected to the mirror surface of the movable lens, and a limiting column is provided on the inclined plane driven structure;

[0009] The outermost edge of the spring structure is fixed to the housing of the movable lens, and the innermost edge is fixed to the inclined surface driven structure; the inclined surface driven structure can use the elastic force of the spring structure to perform a downward movement;

[0010] A housing having a notch structure and a housing protrusion structure;

[0011] When the stator structure generates standing waves or traveling waves under the excitation and drive of external signals, the stator protrusion structure makes an elliptical motion, and the elliptical motion drives the friction layer, the magnetic material layer and the inclined plane driving structure in the rotor structure to make a rotational motion; during the rotation process, the rotational direction freedom is constrained by cooperating with the limiting column and the slot structure, and the inclined plane driven structure makes a linear motion along the optical axis, and the outer edge of the shell protrusion structure and the rotor structure play a limiting role in the plane direction.

[0012] Furthermore, according to the requirement of friction self-locking, the inclined plane angle θ of the inclined plane driving structure is not greater than arctan (μ), and the static friction coefficient μ is the maximum static friction coefficient between the inclined plane driven structure and the inclined plane driving structure.

[0013] Furthermore, it also includes a circuit substrate, which is used to lead out the ultrasonic micromotor drive signal line; and a magnetoresistive detection sensor is set on the circuit substrate, which is used to measure the magnetic field change during rotation, and the rotation angle of the rotor structure is obtained by inverse calculation through the sensor's induction structure, and the distance the movable lens moves forward or backward is obtained by inverse calculation through the detected rotation angle.

[0014] Furthermore, when the inclined plane driving structure rotates clockwise, the inclined plane driven structure moves upward, and the lens also moves upward. Conversely, when the inclined plane driving structure rotates counterclockwise, the lens and the inclined plane driven structure move downward due to the downward pressure of the elastic force of the spring structure.

[0015] Furthermore, the shape of the housing protrusion structure includes an arc-shaped protrusion, which is arranged on the periphery of the rotor structure and is in linear contact with the rotor, thereby playing the role of bearing limit.

[0016] Furthermore, a mounting surface is provided on the housing, and the lower surface of the outer edge of the spring structure is mounted in cooperation with the mounting surface of the housing of the movable lens.

[0017] Furthermore, the bevel includes a square thread bevel, a triangular or trapezoidal bevel.

[0018] Furthermore, the inclined plane driving structure includes a spliced array structure, and the number of arrays is adjusted according to actual design.

[0019] Furthermore, the spliced array structure includes any one of a three-segment spliced array structure, a two-segment spliced array structure and a four-segment spliced array structure.

[0020] A camera module comprises a camera focusing mechanism based on an ultrasonic micromotor structure as described in any one of the above items.

[0021] The beneficial effects of the present invention include:

[0022] The present invention can achieve higher adjustment accuracy and faster response speed, making it more suitable for embedding into camera module structures for terminal applications such as mobile phones. Specifically, a new overall structure based on ultrasonic micromotor drive is proposed. The threaded bevel drive structure of the rotor structure drives the lens structure to convert rotational motion into linear motion, which serves as a focusing function. The bevel drive structure has a self-locking capability, that is, when the ultrasonic motor stops driving, the lens structure maintains its displacement. The rotor structure is improved with an integrated design consisting of three parts: a bevel drive structure, a magnetic material layer structure, and a friction layer structure. The bevel structure drives the bevel up and down, and the magnetic material provides a rotating magnetic field for angle detection and stator-rotor preload. The friction layer cooperates with the stator to achieve optimal friction drive efficiency and wear resistance. The design of the driven bevel structure is innovative. The upper part of the bevel has an elastic structure that acts as a spring, providing a restoring force or preload. The side limit posts cooperate with the notches in the housing to limit the degree of freedom of rotation, so that it can only perform rotational motion under the drive of the ultrasonic micromotor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] 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 or the description of the prior art. 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.

[0024] Figure 1 This is a first structural diagram of an embodiment of the present invention;

[0025] Figure 2 This is a second structural diagram of an embodiment of the present invention;

[0026] Figure 3 This is a third structural diagram of an embodiment of the present invention;

[0027] Figure 4 This is a fourth structural diagram of an embodiment of the present invention.

[0028] In the figure, 200-fixed lens part, 20-fixed frame, 21-lens, 30-photosensitive chip unit, 31-photosensitive chip unit substrate; 100-movable lens part, 40-mirror surface, 1-moving part of the movable lens;

[0029] 16-lens base structure, 17-circuit substrate, 171-magnetic resistance detection sensor, 18-stator structure, 181-stator protrusion structure;

[0030] 1345-rotor structure, 13-inclined drive structure, 14-magnetic material layer, 15-friction layer;

[0031] 11-spring structure, 12-inclined driven structure, 120-limiting column;

[0032] 10-shell, 101-notch structure, 102-shell protrusion structure, 103-shell mounting surface. DETAILED DESCRIPTION

[0033] All features disclosed in all embodiments in this specification, or steps in all methods or processes implicitly disclosed, except for mutually exclusive features and / or steps, can be combined and / or expanded or replaced in any manner.

[0034] To address the issues outlined in the background, the applicants of this application, after further creative thinking, concluded that, in addition to the drive mechanism described in the background, they conceived a camera focusing mechanism based on a piezoelectric ultrasonic motor. Further research revealed that a piezoelectric ultrasonic motor (USM) is a novel motor that utilizes ultrasonic vibration energy for drive. Unlike traditional electromagnetic motors, USMs have no magnetic poles or windings and do not rely on electromagnetic interactions to transfer energy. Instead, they use the inverse piezoelectric effect of piezoelectric ceramics (when certain materials are deformed by external forces in a certain direction, polarization occurs inside them, and opposite positive and negative charges appear on their two opposite surfaces. When the external force is removed, they return to an uncharged state. This phenomenon is called the positive piezoelectric effect. When the direction of the force changes, the polarity of the charge also changes. Conversely, when an electric field is applied in the polarization direction of the material, these materials will also deform. When the electric field is removed, the deformation of the material disappears. This phenomenon is called the inverse piezoelectric effect). This converts electrical energy into mechanical energy of ultrasonic vibration (mechanical vibration frequency 20KHz). Then, through the contact and friction between the stator and rotor, the alternating vibration is converted into unidirectional rotation or linear motion of the rotor, realizing the conversion of mechanical vibration energy into rotor kinetic energy.

[0035] The driving principle of ultrasonic motors reveals that they offer high positioning accuracy, high torque at low speeds, no need for a reduction gear mechanism, direct drive capability, self-locking upon power failure, simple structure, wide flexibility in motor shape design, low noise, and no electromagnetic interference. These characteristics, unlike electromagnetic motors, have led to specific applications. In 1987, Canon officially introduced a ring-shaped ultrasonic motor based on bulk PZT in camera autofocus systems. In previous camera autofocus systems, the electromagnetic motor was mounted in the rear body of the camera, driving the lens through a series of transmission mechanisms, including a reduction gear mechanism. Due to factors such as backlash and inertia in the transmission system, response times typically exceeded 100ms, resulting in low positioning accuracy. However, the hollow structure of the ring-shaped ultrasonic motor perfectly matches the optical structure of the lens. Mounted on the periphery of the lens, it directly drives the lens without any intermediate transmission, resulting in faster response times (typically within 10ms) and improved positioning accuracy. This also meets the camera's requirements for excellent controllability and low noise.

[0036] With technological advancements and developments, including piezoelectric film and micromachining, ultrasonic micromotors based on PZT piezoelectric film and microfabrication are now capable of being embedded in camera modules for mobile phones and other terminal applications, while meeting application requirements such as power consumption and size. However, technical challenges remain, such as further reducing drive voltage and power consumption, improving response speed, and enhancing adjustment accuracy.

[0037] In the present invention, a technical solution for a camera focusing mechanism and a corresponding module based on an ultrasonic micromotor structure is specifically provided. In the corresponding focusing mechanism, a piezoelectric ultrasonic micromotor made based on piezoelectric film and micromachining technology is used to achieve drive. The driving voltage of a block-based piezoelectric ultrasonic motor is as high as hundreds of volts, while the micro-ultrasonic motor and driving circuit driven by a piezoelectric film in the present invention are smaller in size and require a lower driving voltage, which is more conducive to being embedded in the camera module structure of terminal applications such as mobile phones. On this basis, a new overall focusing mechanism structure based on ultrasonic micromotor drive is proposed, and the integrated structural form and driving structural form of the rotor structure of the piezoelectric ultrasonic micromotor in the focusing mechanism are improved accordingly.

[0038] In a preferred embodiment 1 of the present invention, a camera focusing mechanism based on an ultrasonic micromotor structure is specifically provided. This improves the overall focusing structure based on ultrasonic micromotor drive. The inclined surface driving structure of the rotor structure drives the lens structure to convert rotational motion into linear motion, thereby achieving a focusing function. Specifically, the mechanism includes:

[0039] The piezoelectric film-driven ultrasonic micromotor has a rotor structure with an inclined drive structure, a magnetic material layer, and a friction layer. The inclined drive structure is fixedly connected to the magnetic material layer and the friction layer. The magnetic material layer provides a rotating magnetic field when the rotor structure rotates. The stator structure has a stator protrusion structure. The stator protrusion structure contacts the friction layer and drives the rotor structure to rotate through friction.

[0040] The inclined plane driven structure is integrally fixedly connected to the mirror surface of the movable lens, and a limiting column is provided on the inclined plane driven structure;

[0041] The outermost edge of the spring structure is fixed to the housing of the movable lens, and the innermost edge is fixed to the inclined surface driven structure; the inclined surface driven structure can use the elastic force of the spring structure to perform a downward movement;

[0042] A housing having a notch structure and a housing protrusion structure;

[0043] When the stator structure generates standing waves or traveling waves under the excitation and drive of external signals, the stator protrusion structure makes an elliptical motion, and the elliptical motion drives the friction layer, the magnetic material layer and the inclined plane driving structure in the rotor structure to make a rotational motion; during the rotation process, the rotational direction freedom is constrained by cooperating with the limiting column and the slot structure, and the inclined plane driven structure makes a linear motion along the optical axis, and the outer edge of the shell protrusion structure and the rotor structure play a limiting role in the plane direction.

[0044] In this embodiment, the integrated design of the rotor structure consists of three main components: an inclined plane driving structure, a magnetic material structure, and a friction layer structure. The inclined plane structure drives the inclined plane up and down. The magnetic material provides a rotating magnetic field that can be used for angle detection. The friction layer cooperates with the stator to achieve optimal friction drive efficiency and wear resistance. The rotor structure is surrounded by a shell protrusion structure that can achieve line contact with the rotor structure and serve as a bearing limiter. The inclined plane driven structure is designed with an elastic structure on its upper portion that acts as a spring, providing a restoring force or preload. The side limit posts cooperate with the notch structure of the shell to limit the degree of freedom of rotation, so that it can only move in the direction of rotation when driven by the ultrasonic micromotor.

[0045] In a further embodiment, based on the above embodiment, the driving mode of the inclined surface structure is provided with self-locking capability. According to the requirement of friction self-locking, the inclined surface angle θ of the inclined surface driving structure is not greater than arctan (μ), and the static friction coefficient μ is the maximum static friction coefficient between the inclined surface driven structure and the inclined surface driving structure.

[0046] In other optional embodiments, based on the above embodiments, a circuit substrate is further included, and an ultrasonic micromotor drive signal line is led out using the circuit substrate; and a magnetoresistive detection sensor is provided on the circuit substrate, and the magnetoresistive detection sensor is used to measure the change of the magnetic field during rotation, and the rotation angle of the rotor structure is obtained by inverse calculation through the induction structure of the sensor, and the distance the movable lens moves forward or backward is obtained by inverse calculation through the detected rotation angle.

[0047] In other optional embodiments, based on the above embodiments, when the inclined plane driving structure rotates clockwise, the inclined plane driven structure moves upward, and the lens also moves upward. Conversely, when the inclined plane driving structure rotates counterclockwise, the lens and the inclined plane driven structure move downward due to the downward pressure of the elastic force of the spring structure.

[0048] In other optional implementations, based on the above embodiments, the shape of the shell protrusion structure can be designed as an arc-shaped protrusion, which is arranged on the periphery of the rotor structure and is in linear contact with the rotor, thereby playing the role of bearing limiter.

[0049] In other optional implementations, based on the above embodiment, a mounting surface is further provided on the housing, and the lower surface of the outer edge of the spring structure is mounted in cooperation with the mounting surface of the housing of the movable lens.

[0050] In other optional implementations, based on the above embodiments, the inclined surface can be designed as any one of a square thread inclined surface, a triangular or a trapezoidal inclined surface.

[0051] In other optional implementations, based on the above embodiments, the inclined plane driving structure may be designed as a spliced array structure, and the number of arrays may be adjusted according to actual design.

[0052] In other optional implementations, based on the above embodiments, the spliced array structure can be designed as any one of a three-segment spliced array structure, a two-segment spliced array structure, and a four-segment spliced array structure.

[0053] In a second preferred embodiment of the present invention, a camera module is specifically provided, which is provided with a camera focusing mechanism based on an ultrasonic micromotor structure as described in any one of the above embodiments, and related electronic equipment using the camera module.

[0054] The following further describes the technical solutions of the embodiments of the present invention in conjunction with the accompanying drawings and more detailed technical details:

[0055] like Figure 1 、 Figure 2 and Figure 3As shown, a camera focusing mechanism based on an ultrasonic micromotor structure is first provided, comprising a fixed lens portion 200 and a movable lens portion 100. The fixed lens portion 200 (composed of a fixed frame 20 and a lens 21) is positioned above a photosensitive chip unit 30 and its substrate (photosensitive chip unit substrate 31). The movable lens portion 100 is fixed to the fixed lens portion 200. Reference numeral 1 denotes the moving portion of the movable lens. The movable lens portion 100 further comprises a mirror 40, a housing 10, a lens base structure 16, a circuit substrate 17, a stator structure 18, a rotor structure 1345, a spring structure 11, and an inclined surface driven structure 12. The inclined surface driven structure 12 is integrally fixed to the movable lens mirror 40. When the ultrasonic micromotor is rotated, the mirror 40 is driven to move up and down along the optical axis, achieving automatic focusing. The outermost extension of the spring structure 11 is fixed to the movable lens housing 10, while the innermost edge is fixed to the inclined surface driven structure 12. The fixing method includes, but is not limited to, bonding or welding.

[0056] The integrated design structure of the rotor structure 1345 includes an inclined drive structure 13, a magnetic material layer 14 and a friction layer 15. The inclined drive structure 13 is fixed to the magnetic material layer 14 and the friction layer 15 provided in the rotor structure 1345 of the ultrasonic micromotor; a stator protrusion structure 181 is provided on the stator structure 18, and the stator protrusion structure 181 of the stator structure 18 contacts the friction layer 15 of the rotor structure 1345 of the ultrasonic micromotor, and the rotor structure is driven to rotate by friction. When the stator structure 18 of the ultrasonic micromotor is subjected to an external sinusoidal wave signal, the stator structure 18 of the ultrasonic micromotor rotates. Driven by the excitation, standing waves or traveling waves are generated, causing the stator protrusion structure 181 to perform elliptical motion. The elliptical motion drives the friction layer 15, magnetic material layer 14, and inclined plane drive structure 13 in the rotor structure 1345 to rotate. When the inclined plane drive structure 13 rotates clockwise, the inclined plane driven structure 12 moves upward, and the lens 40 also moves upward. Conversely, when the inclined plane drive structure 13 rotates counterclockwise, the elastic force of the spring structure 11 presses downward, causing the lens 40 and the inclined plane driven structure 12 to move downward. The inclined plane drive structure drives the inclined plane up and down, and the magnet provides a rotating magnetic field for angle detection. The friction layer cooperates with the stator structure to achieve optimal friction drive efficiency and wear resistance.

[0057] The circuit substrate 17 is an FPC flexible circuit substrate for leading out the ultrasonic micromotor drive signal line. A magnetoresistive detection sensor 171 is provided on the circuit substrate 17. When the ultrasonic micromotor stator structure drives the friction layer 15, the magnetic material layer 14 and the inclined plane drive structure 13 in the rotor structure to rotate, the magnetic material layer 14 can be set to a magnet ring shape. Since the magnet ring is bonded or welded to the inclined plane drive structure 13 and the friction layer 15, when the rotor structure 1345 rotates, the magnetic field generated by the magnet in the magnetic material layer 14 changes. The magnetic field change can be measured by the magnetoresistive sensor 171, and the rotation angle of the rotor can be inversely calculated through the sensor's induction structure. The distance the movable lens moves forward or backward can be inversely calculated through the detected rotation angle.

[0058] The base structure 16 of the movable lens is mounted on the fixed frame 20 , the fixed frame 20 is mounted on the base 31 , and the photosensitive chip unit 30 is mounted at the center of the lens.

[0059] The movable lens portion is the core of this application, and its specific operating principle is further described here: A limiting post 120 is provided on the inclined-plane driven structure 12, and a notch structure 101 and a housing protrusion 102 are provided on the movable-lens housing 10. When the ultrasonic micromotor's stator structure 18 is vibrated, it drives the rotor structure 1345 to rotate, and the inclined surface of the inclined-plane driving structure 13 drives the inclined-plane driven structure 12. At this time, because the limiting post 120 of the inclined-plane driven structure 12 cooperates with the notch structure 101 of the movable-lens housing 10, the rotational freedom is strictly constrained. Therefore, under the rotational drive of the rotor structure 1345, the inclined-plane driven structure 12 can only move linearly along the optical axis. When the rotor structure 1345 rotates, the housing protrusion 102 on the movable-lens housing 10 and the outer edge of the rotor structure 1345 act as in-plane limiters, limiting its rotational freedom. The housing protrusion structure 102 is designed as an arc-shaped protrusion, which is arranged on the periphery of the rotor and can be in linear contact with the rotor, acting as a bearing limiter. The outer lower surface of the spring structure 11 is mounted on the housing mounting surface 103 of the movable lens housing 10.

[0060] The bevel angle of the bevel drive structure 13 is one of the key points. A balance must be found between self-locking and efficiency. In view of the self-locking requirements of this application, the bevel angle cannot be designed to be too large, such as Figure 4In the example shown, the bevel angle is the angle between the thread bevel and the plane perpendicular to the axis, but it should be noted that the bevel can not only be a square thread bevel, but can also be designed as a triangular or trapezoidal bevel according to needs. The angle of the bevel is determined by the stroke of the linear motion, the friction coefficient between the bevel driven structure 12 and the bevel driving structure 13. According to the requirements of friction self-locking, the bevel angle θ is not greater than arctan (μ), and the static friction coefficient μ is the maximum static friction coefficient between the bevel driven structure 12 and the bevel driving structure 13. Figure 4 The inclined surface structure in the embodiment is a three-section spliced array, and the number of the arrays can also be adjusted according to the actual design, such as 2 or 4.

[0061] In summary, compared to focusing mechanisms driven by voice coil motors, the technical solution of the present invention, based on a piezoelectric ultrasonic micromotor, can achieve low-speed, high-torque performance, requires no reduction gearing, can be driven directly, and self-locks when powered off, resulting in lower energy consumption. The motor's structural design facilitates focusing, offers advantages in size, facilitates thinning and miniaturization, and reduces noise levels in the ultrasonic frequency band. Compared to solutions using bulk piezoelectric materials, the ultrasonic micromotor of the present invention, using piezoelectric film, is thinner and has a lower drive voltage. Bulk piezoelectric ultrasonic motors can achieve drive voltages of up to hundreds of volts. The piezoelectric film-driven microultrasonic motor and its drive circuit are smaller, making it more suitable for integration into camera modules for mobile phones and other terminal applications. The technical solution of the present invention utilizes a rotor structure with an inclined drive structure to drive the lens structure, converting rotational motion into linear motion, thus achieving a focusing function. Furthermore, the inclined drive structure has a self-locking capability. Compared to solutions using memory alloy wire heating or electromagnetic motors, which have slow response speeds of tens or hundreds of milliseconds, the piezoelectric response of the present invention is faster, and combined with angle detection, it can achieve higher precision in closed-loop control.

[0062] The above description is merely the technical principles and preferred embodiments used in the present invention. Those skilled in the art will appreciate that the present invention is not limited to the specific embodiments described herein. It is obvious that various changes, adjustments, and substitutions can be made by those skilled in the art without departing from the scope of protection of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the principles and concepts of the present invention, it may also include more other equivalent embodiments, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A camera focusing mechanism based on an ultrasonic micromotor structure, characterized in that: include: The piezoelectric film-driven ultrasonic micromotor has a rotor structure with an inclined drive structure, a magnetic material layer, and a friction layer. The inclined drive structure is fixedly connected to the magnetic material layer and the friction layer. The magnetic material layer provides a rotating magnetic field when the rotor structure rotates. The stator structure has a stator protrusion structure. The stator protrusion structure contacts the friction layer and drives the rotor structure to rotate through friction. The inclined plane driven structure is integrally fixedly connected to the mirror surface of the movable lens, and a limiting column is provided on the inclined plane driven structure; The outermost edge of the spring structure is fixed to the housing of the movable lens, and the innermost edge is fixed to the inclined surface driven structure; the inclined surface driven structure can use the elastic force of the spring structure to perform a downward movement; A housing having a notch structure and a housing protrusion structure; When the stator structure generates standing waves or traveling waves under the excitation of external signals, the stator protrusion structure performs elliptical motion, and the elliptical motion drives the friction layer, magnetic material layer and inclined drive structure in the rotor structure to rotate; During the rotation process, the freedom of the rotation direction is constrained by cooperating with the limiting column and the slot structure, and the inclined surface is driven to move linearly along the optical axis. The shell protrusion structure and the outer edge of the rotor structure play a limiting role in the plane direction.

2. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: According to the requirement of friction self-locking, the inclined plane angle θ of the inclined plane driving structure is not greater than arctan (μ), and the static friction coefficient μ is the maximum static friction coefficient between the inclined plane driven structure and the inclined plane driving structure.

3. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: It also includes a circuit substrate, which is used to lead out the ultrasonic micromotor drive signal line; and a magnetoresistive detection sensor is set on the circuit substrate, which is used to measure the magnetic field change during rotation, and the rotation angle of the rotor structure is obtained by reverse calculation through the sensor's induction structure, and the distance the movable lens moves forward or backward is obtained by reverse calculation through the detected rotation angle.

4. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: When the inclined plane driving structure rotates clockwise, the inclined plane driven structure moves upward, and the lens also moves upward. Conversely, when the inclined plane driving structure rotates counterclockwise, the lens and the inclined plane driven structure move downward due to the downward pressure of the elastic force of the spring structure.

5. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: The shape of the housing protrusion structure includes an arc-shaped protrusion, which is arranged on the periphery of the rotor structure and is in linear contact with the rotor, playing the role of bearing limit.

6. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: The housing is also provided with a mounting surface, and the lower surface of the outer edge of the spring structure is matched with the mounting surface of the housing of the movable lens for mounting.

7. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: The inclined surface includes a square thread inclined surface, a triangular or trapezoidal inclined surface.

8. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 1, characterized in that: The inclined plane driving structure includes a spliced array structure, and the number of arrays is adjusted according to actual design.

9. The camera focusing mechanism based on the ultrasonic micromotor structure according to claim 8, characterized in that: The spliced array structure includes any one of a three-segment spliced array structure, a two-segment spliced array structure and a four-segment spliced array structure.

10. A camera module, characterized in that: The invention comprises a camera focusing mechanism based on an ultrasonic micromotor structure as described in any one of claims 1 to 9.

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