Variable aperture structure based on ultrasonic micro motor, camera module and method for stepless adjustment of aperture

Abstract

The invention belongs to the technical field of aperture structures, and particularly relates to a variable aperture structure based on an ultrasonic micro motor, a camera module and a method for stepless adjustment of an aperture. According to the technical scheme, the variable aperture structure based on the ultrasonic micromotor comprises a fixing frame, a fixing disc is fixedly connected to the top of the fixing frame, an ultrasonic micromotor base is installed in the fixing frame, an ultrasonic micromotor stator is connected to the ultrasonic micromotor base, and a rotor structure is arranged on the upper side of the ultrasonic micromotor stator; a plurality of blades are rotationally connected to the fixing disc in the circumferential direction, the area defined by the blades is an aperture, and a driving structure used for driving the blades to tilt is arranged on the rotor structure. The invention provides a variable aperture structure based on an ultrasonic micro motor, a camera module and a method for stepless adjustment of an aperture, and aims to realize continuous stepless adjustment of the size of the aperture and improve the response speed.

Description

Technical Field

[0001] The present invention belongs to the technical field of aperture structures, and particularly relates to a variable aperture structure based on an ultrasonic micromotor, a camera module, and a method for steplessly adjusting an aperture. Background Art

[0002] With the popularization of mobile terminal devices such as smart phones and tablet computers, users have higher and higher requirements for shooting quality. To meet this demand, the camera modules of terminal devices are continuously upgraded, and the adjustable aperture technology has become one of the focuses of attention in recent years. An adjustable aperture can optimize the imaging effect by adjusting the amount of incident light, especially in complex lighting conditions, which can significantly improve the shooting quality.

[0003] The aperture is a key component in a lens that controls the amount of incident light. In traditional cameras, the aperture size is adjusted through a mechanical structure to achieve different depths of field and exposure effects. However, in thin and light devices such as mobile phones and tablets, due to space limitations, traditional mechanical apertures are difficult to directly apply. Therefore, developing miniaturized and high-precision adjustable aperture technologies suitable for mobile terminals has become an important research direction in the industry.

[0004] The main advantages of mechanical adjustable apertures include:

[0005] Dynamic adjustment of the amount of incident light: In strong light or weak light environments, the exposure effect is optimized by adjusting the aperture size.

[0006] Control of the depth of field: By adjusting the aperture size, the background blurring effect is achieved, improving the shooting quality of portraits.

[0007] Improvement of imaging quality: Reducing overexposure or underexposure phenomena, improving the dynamic range and detail performance.

[0008] Electromagnetic drive technology is one of the currently widely used adjustable aperture implementation schemes. Its basic principle is to drive the opening and closing of aperture blades through electromagnetic force, thereby adjusting the aperture size. The patent with the publication number CN115480433B discloses a variable aperture, a camera module, and an electronic device. This invention patent uses electromagnetic drive, and through the cooperation of a magnet coil, the magnetic force drive is realized. The magnetic force drives the blade to swing, thereby realizing the adjustment of the aperture hole. The patent with the publication number CN218350671U discloses a variable aperture drive motor, a camera device, and an electronic device. This invention patent uses a paired combination of multiple sets of magnets and coils. By energizing the coil, an electromagnetic force is generated to drive the blade group to open and close, thereby realizing the adjustment of the aperture diameter. Electromagnetic drive can achieve precise control of aperture blades. The electromagnetic drive mechanism can be designed to be relatively small and suitable for the space limitations of mobile terminal devices. Electromagnetic drive technology is mature, has high reliability, long service life, and is suitable for large-scale production.

[0009] Shape memory alloy is a material with shape memory function, which can restore the preset shape when the temperature changes. Utilizing this property, shape memory alloy can be used to drive the movement of aperture blades. The patent with the publication number CN115268173B discloses a variable aperture, camera module and electronic device. This invention patent uses shape memory alloy drive. By energizing and heating the shape memory alloy wire, the turntable is driven to rotate, and the turntable fluctuates the blades to swing, thereby adjusting the aperture hole. The shape memory alloy drive mechanism does not require a complex mechanical structure and can further reduce the volume of the module. The drive of the shape memory alloy depends on temperature change, so the deformation of the shape memory alloy requires a certain amount of time and its response speed is relatively slow.

[0010] Whether it is electromagnetic drive or shape memory alloy drive, the existing aperture drive has fewer gears and cannot change the aperture size in multiple gears. For the scheme of heating the shape memory alloy wire or driving by an electromagnetic motor, the response speed is slow in the order of ten or one hundred milliseconds. Summary of the Invention

[0011] In order to solve the above problems existing in the prior art, the purpose of the present invention is to provide a variable aperture structure based on an ultrasonic micromotor, a camera module and a method for steplessly adjusting the aperture, so as to realize continuous stepless adjustment of the aperture size and improve the response speed.

[0012] The technical solution adopted by the present invention is as follows:

[0013] A variable aperture structure based on an ultrasonic micromotor includes a fixed frame. A fixed disk is fixedly connected to the top of the fixed frame. An ultrasonic micromotor base is installed in the fixed frame. An ultrasonic micromotor stator is connected to the ultrasonic micromotor base. A rotor structure is arranged on the upper side of the ultrasonic micromotor stator. A plurality of blades are rotatably connected to the fixed disk along the circumferential direction. The area enclosed by the plurality of blades is the aperture. A driving structure for driving the plurality of blades to tilt is arranged on the rotor structure.

[0014] When the driving signal of the ultrasonic micromotor starts to drive, the working mode of the ultrasonic micromotor stator is excited, and the rotor structure is driven to rotate by friction. While the rotor structure rotates, it drives the blades to rotate around the shaft structure between the blades and the fixed disk.

[0015] Whether it is electromagnetic drive or shape memory alloy drive, the existing aperture drive has fewer gears and cannot change the aperture size in multiple gears. The present invention adopts a variable aperture structure based on an ultrasonic micromotor. After receiving the driving signal, the ultrasonic micromotor stator fluctuates along the circumferential direction, and the rotor structure is driven to rotate by the frictional force during the fluctuation. The rotor structure drives the blades to rotate to realize the adjustment of the aperture size. Since the ultrasonic micromotor stator can drive the rotor structure to rotate a determined angle, the present invention can continuously and steplessly adjust the aperture size. The resolution depends on the accuracy of rotation control. Due to the high resolution of piezoelectric friction drive, the aperture adjustment gears are much more than the current aperture adjustment methods.

[0016] The variable aperture structure of the present invention is a monolithic structure driven by an ultrasonic micromotor. Due to the extremely small thickness of the ultrasonic motor based on PZT piezoelectric film, it can be directly embedded in the aperture module. The rotor structure integrates the unit that drives the blades. Rotation of the rotor structure drives the blades, thus opening and closing the fan blades. The integration of the drive motor and the aperture mechanism enables the variable aperture structure of the present invention to be embedded in thin lenses.

[0017] Solutions using memory alloy wire heating or electromagnetic motor drive have slow response speeds of tens or hundreds of milliseconds. The present invention uses a piezoelectric film-based ultrasonic micromotor, which has a fast response speed and can maintain the aperture position after power failure, without consuming energy during the maintenance process, thus reducing energy consumption.

[0018] As a preferred embodiment of the present invention, the rotor structure comprises a friction layer ring, a magnet ring, and a rotating dial, which are fixed in sequence. The friction layer ring contacts the ultrasonic micromotor stator, and the drive structure is mounted on the rotor structure. Upon receiving a drive signal, the ultrasonic micromotor stator oscillates circumferentially, and the frictional force of this oscillation drives the friction layer ring to rotate. The magnet ring and rotating dial then rotate with the friction layer ring, and the drive structure on the rotating dial drives the blades. The friction layer ring, magnet ring, and rotating dial are integrated into a single unit, reducing the thickness of the device.

[0019] As a preferred embodiment of the present invention, the ultrasonic micromotor stator is equipped with a plurality of protrusions on the side closest to the friction layer ring. Upon receiving a drive signal, the ultrasonic micromotor stator oscillates circumferentially. The protrusions produce elliptical motion in response to the vibrations of the ultrasonic micromotor stator, driving the friction layer ring to rotate. When the protrusions contact the friction layer ring, the radial component of force exerted by the protrusions propels the friction layer ring to rotate.

[0020] As a preferred embodiment of the present invention, the driving structure of the rotary dial comprises a plurality of notches, with columnar structures fixed to the blades and nested within the notches. When the rotary dial is rotated, the notches on the rotary dial move the columnar structures on the blades, thereby driving the blades to rotate about an axis structure fixed to the fixed plate. The axis structure is secured to the fixed plate. The angle of rotation of the rotary dial corresponds to the aperture formed by the blades, allowing the aperture to be precisely adjusted by controlling the rotation angle of the rotor structure.

[0021] As a preferred solution of the present invention, the distance from one end of the notch structure to the center of the rotating dial gradually increases from one end to the other end.

[0022] As a preferred embodiment of the present invention, a plurality of smooth limiting posts are rotatably mounted on the inner wall of the fixed frame, and the friction layer ring cooperates with the smooth limiting posts. To ensure stable rotation of the rotor structure within the fixed frame, the friction layer ring of the rotor structure and the smooth limiting posts of the fixed frame form a slight clearance fit, functioning as a bearing.

[0023] As a preferred embodiment of the present invention, a first FPC substrate is mounted on the ultrasonic micromotor base, the solder pads of the first FPC substrate are electrically connected to the lower surface of the ultrasonic micromotor stator, and the driving signal of the ultrasonic micromotor stator is introduced through the flexible first FPC substrate.

[0024] As a preferred embodiment of the present invention, the PZT piezoelectric film layer of the ultrasonic micromotor stator is located on the bottom surface, and the excitation mode electrode layer is located on the surface of the PZT piezoelectric film. The excitation mode electrode layer closely mates with the solder pads of the first FPC substrate. The solder pads of the first FPC substrate closely mate with and are electrically connected to the bottom surface of the ultrasonic micromotor stator.

[0025] As a preferred embodiment of the present invention, a second FPC substrate is mounted on the ultrasonic micromotor base. The first and second FPC substrates are electrically connected, and the second FPC substrate is electrically connected to a magnetoresistive sensor for detecting the rotation angle of the rotor structure. The magnetoresistive sensor is soldered to the second FPC substrate to detect the rotation angle of the rotor structure. By detecting the angle of the rotor structure, the aperture opening and closing can be directly determined, facilitating precise adjustment of the aperture size.

[0026] As a preferred embodiment of the present invention, the ultrasonic micromotor base is provided with an annular protrusion, to which the ultrasonic micromotor stator is fixed. To improve the resonant Q value of the ultrasonic micromotor, a central fixing method is adopted to minimize anchor point losses. Specifically, the annular protrusion in the middle of the ultrasonic micromotor base is fixed to the lower surface of the ultrasonic micromotor stator.

[0027] A camera module includes a variable aperture structure based on an ultrasonic micromotor and a substrate. A photosensitive chip is mounted on the substrate. A lens is located on one side of the photosensitive chip and is positioned on the side of a fixed frame away from a fixed plate. The variable aperture structure is located directly above the lens, and the photosensitive chip is located directly below and in the middle of the lens. The photosensitive chip is mounted on the substrate.

[0028] As a preferred solution of the present invention, it further comprises a housing, and the lens is arranged in the housing.

[0029] A method for steplessly adjusting an aperture comprises the following steps:

[0030] S1: Send a driving signal to the stator of the ultrasonic micromotor. After receiving the driving signal, the stator of the ultrasonic micromotor fluctuates in the circumferential direction. The convex points on the stator perform elliptical motion along with the vibration of the stator and drive the rotation of the rotor structure.

[0031] S2: While the rotor structure rotates, it drives the columnar structure on the blade through the notch structure to drive the blade to rotate around the shaft structure between the fixed disks.

[0032] As a preferred solution of the present invention, a number of smooth limiting columns are rotatably arranged on the inner wall of the fixed frame; in step S1, when the rotor structure rotates, the friction layer ring rolls and rubs against the smooth limiting columns.

[0033] The beneficial effects of the present invention are as follows:

[0034] 1. The present invention adopts a variable aperture structure based on an ultrasonic micromotor. After the stator of the ultrasonic micromotor receives the driving signal, it fluctuates in the circumferential direction. The rotor structure is driven to rotate by the frictional force during the fluctuation, and the rotor structure drives the blade to rotate to realize the adjustment of the aperture size. Since the stator of the ultrasonic micromotor can drive the rotor structure to rotate a determined angle, the present invention can continuously and steplessly adjust the aperture size. The resolution depends on the accuracy of rotation control. Due to the high resolution of piezoelectric friction drive, the aperture adjustment gears are much more than the current aperture adjustment methods.

[0035] 2. The variable aperture structure of the present invention is an overall structural form based on ultrasonic micromotor drive. Since the ultrasonic motor based on PZT piezoelectric film has an extremely small thickness, it can be directly embedded in the aperture module. The rotor structure integrates the unit for driving the blade to rotate. The rotation of the rotor structure drives the blade to rotate, performing the function of opening and closing the fan blade. The integration of the driving motor and the aperture mechanism of the present invention enables the variable aperture structure of the present invention to be embedded in a thin lens.

[0036] 3. The present invention adopts an ultrasonic micromotor based on piezoelectric film, which has a fast response speed, and can maintain the aperture position after power-off. No energy is consumed during the maintaining process, which can reduce energy consumption. Description of the Drawings

[0037] Figure 1 is the structural schematic diagram of the present invention;

[0038] Figure 2 is the assembly drawing of the present invention;

[0039] Figure 3 is the partial structural drawing of the variable aperture structure;

[0040] Figure 4 is the assembly drawing of the blade and the rotating dial.

[0041] In the figure: 010 - variable aperture structure; 20 - lens; 30 - substrate; 31 - photosensitive chip; 1234 - rotor structure; 200 - housing;

[0042] 10 - fixed disk; 101 - shaft structure; 11 - blade; 110 - columnar structure; 12 - rotating dial; 120 - notch structure; 13 - magnet ring; 131 - first half magnet ring; 132 - second half magnet ring; 14 - friction layer ring; 15 - ultrasonic micromotor stator; 16 - first FPC substrate; 17 - first FPC substrate; 171 - magnetoresistive sensor; 18 - ultrasonic micromotor base; 19 - fixed frame; 191 - smooth limit post. Detailed implementation manners

[0043] To make the objectives, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. Usually, the components of the embodiments of the present invention described and illustrated herein can be arranged and designed in various different configurations.

[0044] Therefore, the following detailed description of the embodiments of the present invention provided in the drawings is not intended to limit the scope of the claimed present invention, but merely represents selected embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts fall within the scope of protection of the present invention. It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0045] As Figures 1 to 4 shown, the variable aperture structure based on an ultrasonic micromotor in this embodiment includes a fixed frame 19. A fixed disk 10 is fixedly connected to the top of the fixed frame 19. An ultrasonic micromotor base 18 is installed in the fixed frame 19. An ultrasonic micromotor stator 15 is connected to the ultrasonic micromotor base 18. A rotor structure 1234 is arranged on the upper side of the ultrasonic micromotor stator 15. A plurality of blades 11 are rotatably connected to the fixed disk 10 along the circumferential direction. The area enclosed by the plurality of blades 11 is the aperture. A driving structure for driving the plurality of blades 11 to tilt is arranged on the rotor structure 1234.

[0046] When the driving signal of the ultrasonic micromotor starts to drive, the working mode of the ultrasonic micromotor stator 15 is excited, and the rotor structure 1234 is rotated by frictional drive. While the rotor structure 1234 rotates, it drives the blades 11 to rotate around the shaft structure 101 between the blades 11 and the fixed disk 10. Among them, mode: the inherent vibration characteristics of any structure. When the structure resonates, the mode refers to the characteristic values of the resonance frequency and vibration mode of the structure.

[0047] Whether it is electromagnetic drive or shape memory alloy drive, the existing aperture drive has fewer gears and cannot change the aperture size in multiple gears. The variable aperture structure 010 of the present invention adopts an ultrasonic micromotor-based structure. After receiving a driving signal, the ultrasonic micromotor stator 15 fluctuates in the circumferential direction and drives the rotor structure 1234 to rotate through the frictional force during the fluctuation. The rotor structure 1234 drives the blade 11 to rotate, realizing the adjustment of the aperture size. Since the ultrasonic micromotor stator 15 can drive the rotor structure 1234 to rotate a certain angle, the present invention can continuously and steplessly adjust the aperture size, and the resolution depends on the accuracy of rotation control. Due to the high resolution of piezoelectric friction drive and the cooperation with high-precision angle detection, the opening and closing angle of the aperture can be adjusted in a closed loop, and the number of aperture adjustment gears is much larger than the current aperture adjustment method.

[0048] The variable aperture structure 010 of the present invention is an overall structure form based on ultrasonic micromotor drive. Since the ultrasonic motor based on PZT piezoelectric film has an extremely small thickness, it can be directly embedded in the aperture module. The rotor structure 1234 integrates the unit for driving the blade 11 to rotate. When the rotor structure 1234 rotates, it drives the blade 11 to rotate, performing the function of opening and closing the fan blade. The driving motor of the present invention is integrated with the aperture mechanism, enabling the variable aperture structure 010 of the present invention to be embedded in a thin form with the lens 20.

[0049] The solutions using shape memory alloy wire heating or electromagnetic motor drive have a slow response speed in the order of ten or one hundred milliseconds. The present invention adopts an ultrasonic micromotor based on piezoelectric film, which has a fast response speed, can maintain the aperture position after power-off, does not consume energy during the holding process, and can reduce energy consumption.

[0050] Piezoelectric effect: When some materials are deformed under the action of an external force in a certain direction, polarization phenomena will occur inside them, and at the same time, positive and negative charges with opposite polarities will appear on its two opposite surfaces. When the external force is removed, it will return to the uncharged state again. This phenomenon is called the direct piezoelectric effect. When the direction of the acting force changes, the polarity of the charge also changes accordingly. On the contrary, when an electric field is applied in the polarization direction of the material, these materials will also deform, and when the electric field is removed, the deformation of the material will disappear. This phenomenon is called the inverse piezoelectric effect.

[0051] Specifically, as Figure 1As shown, the rotor structure 1234 comprises a friction layer ring 14, a magnet ring 13, and a rotating dial 12, which are fixed in sequence. The friction layer ring 14 contacts the ultrasonic micromotor stator 15, and the drive structure is mounted on the rotor structure 1234. Upon receiving a drive signal, the ultrasonic micromotor stator 15 oscillates circumferentially. The friction force of this oscillation drives the friction layer ring 14 to rotate, which in turn causes the magnet ring 13 and rotating dial 12 to rotate along with the friction layer ring 14. The drive structure on the rotating dial 12 drives the blades 11 to rotate. The friction layer ring 14, magnet ring 13, and rotating dial 12 are integrated into a single unit, reducing the thickness of the device.

[0052] The ultrasonic micromotor stator 15 is equipped with several protrusions on one side near the friction layer ring 14. Upon receiving a drive signal, the ultrasonic micromotor stator 15 oscillates circumferentially. The protrusions follow the oscillation of the ultrasonic micromotor stator 15 in an elliptical motion, driving the friction layer ring 14 to rotate. When the protrusions contact the friction layer ring 14, the radial force component of the protrusions propels the friction layer ring 14 to rotate.

[0053] like Figure 4 As shown, the driving structure on the rotating dial 12 comprises a plurality of notched structures 120. A columnar structure 110 is fixed to the blade 11 and is sleeved within the notched structures 120. When the rotating dial 12 rotates, the notched structures 120 on the rotating dial 12 move the columnar structure 110 on the blade 11, thereby driving the blade 11 to rotate about an axis structure 101 between the rotating dial 12 and the fixed plate 10. The axis structure 101 is fixed to the fixed plate 10. The rotation angle of the rotating dial 12 corresponds to the aperture formed by the plurality of blades 11. Therefore, the aperture size can be precisely adjusted by controlling the rotation angle of the rotor structure 1234.

[0054] It should be noted that the distance from one end of the notch structure 120 to the other end thereof gradually increases from the center of the rotary dial 12 .

[0055] In order to ensure that the rotor structure 1234 rotates stably in the fixed frame 19, the friction layer ring 14 of the rotor structure 1234 and the smooth limiting column 191 of the fixed frame 19 form a clearance fit, which functions as a bearing.

[0056] In order to realize the introduction of the driving signal, a first FPC substrate 16 is installed on the ultrasonic micromotor base 18. The solder pads of the first FPC substrate 16 are electrically connected to the lower surface of the ultrasonic micromotor stator 15. The driving signal of the ultrasonic micromotor stator 15 is introduced through the flexible first FPC substrate 16.

[0057] Specifically, the PZT piezoelectric thin film layer of the ultrasonic micromotor stator 15 is located on the lower surface, and the electrode layer in the excitation mode is located on the surface of the PZT piezoelectric thin film. The electrode layer in the excitation mode is in close fit with the pad of the first FPC substrate 16. The pad of the first FPC substrate 16 is in close fit with and electrically connected to the lower surface of the ultrasonic micromotor stator 15.

[0058] In order to detect the rotation angle of the rotor structure 1234, a second FPC substrate 17 is further installed on the ultrasonic micromotor base 18. The first FPC substrate 16 is electrically connected to the second FPC substrate 17, and a magnetoresistive sensor 171 for detecting the rotation angle of the rotor structure 1234 is electrically connected to the second FPC substrate 17. The magnetoresistive sensor 171 is used to detect the rotation angle of the rotor structure 1234 and is welded on the second FPC substrate 17. By detecting the angle of the rotor structure 1234, the opening and closing size of the aperture can be directly judged to facilitate the precise adjustment of the aperture size.

[0059] A ring-shaped protrusion is provided on the ultrasonic micromotor base 18, and the ultrasonic micromotor stator 15 is fixed on the ring-shaped protrusion of the ultrasonic micromotor base 18. In order to improve the resonant Q value of the ultrasonic micromotor, an intermediate fixing form is adopted to minimize the anchor loss as much as possible, that is, the ring-shaped protrusion in the middle of the ultrasonic micromotor base 18 is fixed to the lower surface of the ultrasonic micromotor stator 15.

[0060] Working principle of the adjustable aperture structure:

[0061] The ultrasonic micromotor's drive signal is introduced through the first FPC substrate 16. The solder pads on the first FPC substrate 16 closely mate with and are electrically connected to the bottom surface of the ultrasonic micromotor stator 15. The PZT piezoelectric film layer of the ultrasonic micromotor stator 15 is located on its bottom surface, while the electrode layer for the motor section that excites the mode is located on the surface of the PZT piezoelectric film. Therefore, the solder pads on its surface are electrically connected to the solder pads on the top surface of the first FPC substrate 16. The ultrasonic micromotor stator 15 is fixed to the annular protrusion on the metal base. When the ultrasonic micromotor drive signal initiates operation, the operating mode of the ultrasonic micromotor stator 15 is excited, driving the rotor structure 1234 to rotate through friction. As the rotor structure 1234 rotates, the notch structure 120 shifts the columnar structure 110 on the blade 11, causing the blade 11 to rotate about the shaft structure 101, which is fixed to the fixed plate 10. The bottom surface of the fixed plate 10 is fixed to the top surface of the fixed frame 19. In order to ensure that the rotor structure 1234 rotates stably in the fixed frame 19, the friction layer ring 14 of the rotor structure 1234 forms a clearance fit with the smooth limit column 191 of the fixed frame 19, acting as a bearing. The rotor structure 1234 is composed of three parts, namely the rotating dial 12, the magnet ring 13 composed of the first half magnet ring 131 and the second half magnet ring 132, and the friction layer ring 14. The magnet ring 13 can be made of nedium iron boron or samarium cobalt material, and the polarization direction of the magnet ring 13 is along the thickness direction. The outer diameter of the friction layer ring 14 is the most protruding, forming a clearance fit with the fixed frame 19. The magnetoresistive sensor 171 is used to detect the rotation angle of the rotor structure 1234, which is welded on the second FPC substrate 17.

[0062] like Figure 2 As shown, the camera module of this embodiment includes a variable aperture structure based on an ultrasonic micromotor and a substrate 30. A photosensitive chip 31 is mounted on the substrate 30. A lens 20 is disposed on one side of the photosensitive chip 31. The lens 20 is located on the side of the fixed frame 19 away from the fixed plate 10. The variable aperture structure 010 is located directly above the lens 20. The photosensitive chip 31 is located directly below and in the middle of the lens 20. The photosensitive chip 31 is mounted on the substrate 30.

[0063] The camera module further includes a housing 200 , in which the lens 20 is disposed.

[0064] The method for steplessly adjusting the aperture of this embodiment includes the following steps:

[0065] S1: Send a driving signal to the ultrasonic micromotor stator 15. After receiving the driving signal, the ultrasonic micromotor stator 15 oscillates in the circumferential direction. The protrusions on the stator perform elliptical motion as the stator vibrates, and drive the rotor structure 1234 to rotate. When the rotor structure 1234 rotates, the friction layer ring 14 and the smooth limit column 191 roll and rub against each other.

[0066] S2: while the rotor structure 1234 rotates, the columnar structure 110 on the blade 11 is moved by the slot structure 120 to drive the blade 11 to rotate around the shaft structure 101 between the blade 11 and the fixed disk 10 .

[0067] The present invention is not limited to the above-mentioned optional implementation modes. Anyone can derive other forms of products under the inspiration of the present invention. However, no matter what changes are made in the shape or structure, any technical solution that falls within the scope defined by the claims of the present invention falls within the scope of protection of the present invention.

Claims

1. A variable aperture structure based on an ultrasonic micromotor, characterized in that: It includes a fixed frame (19), a fixed disk (10) is fixedly connected to the top of the fixed frame (19), an ultrasonic micromotor base (18) is installed in the fixed frame (19), an ultrasonic micromotor stator (15) is connected to the ultrasonic micromotor base (18), a rotor structure (1234) is arranged on the upper side of the ultrasonic micromotor stator (15), a plurality of blades (11) are rotatably connected to the fixed disk (10) along the circumferential direction, the enclosed area of the plurality of blades (11) is an aperture, and a driving structure for driving the plurality of blades (11) to tilt is arranged on the rotor structure (1234).

2. The variable aperture structure based on an ultrasonic micromotor according to claim 1, wherein: The rotor structure (1234) includes a friction layer ring (14), a magnet ring (13) and a rotating dial (12) fixed in sequence. The friction layer ring (14) contacts the ultrasonic micromotor stator (15), and the driving structure is arranged on the rotor structure (1234).

3. The variable aperture structure based on the ultrasonic micromotor according to claim 2, characterized in that: A plurality of bumps are arranged on the side of the ultrasonic micromotor stator (15) close to the friction layer ring (14). After the ultrasonic micromotor stator (15) receives a driving signal, it fluctuates along the circumferential direction, and the bumps push the friction layer ring (14) to rotate along with the fluctuation of the ultrasonic micromotor stator (15).

4. The variable aperture structure based on an ultrasonic micromotor according to claim 2, wherein: The driving structure on the rotating dial (12) is a plurality of notch structures (120), a columnar structure (110) is fixed on the blade (11), and the columnar structure (110) is sleeved in the notch structure (120).

5. The variable aperture structure based on the ultrasonic micromotor according to claim 4, wherein: In the direction from one end to the other end of the notch structure (120), the distance from the center of the rotating dial (12) gradually increases.

6. The variable aperture structure based on an ultrasonic micromotor according to claim 2, wherein: A plurality of smooth limiting columns (191) are rotatably arranged on the inner wall of the fixed frame (19), and the friction layer ring (14) cooperates with the smooth limiting columns (191).

7. The variable aperture structure based on an ultrasonic micromotor according to claim 1, characterized in that: A first FPC substrate (16) is installed on the ultrasonic micromotor base (18). The pads of the first FPC substrate (16) are electrically connected to the lower surface of the ultrasonic micromotor stator (15), and the driving signal of the ultrasonic micromotor stator (15) is introduced through the first FPC substrate (16).

8. The variable aperture structure based on an ultrasonic micromotor according to claim 7, wherein: The PZT piezoelectric thin film layer of the ultrasonic micromotor stator (15) is located on the lower surface, and the electrode layer of the excitation mode is located on the surface of the PZT piezoelectric thin film. The electrode layer of the excitation mode is in close cooperation with the pads of the first FPC substrate (16).

9. The variable aperture structure based on an ultrasonic micromotor according to claim 7, wherein: A second FPC substrate (17) is also installed on the ultrasonic micromotor base (18). The first FPC substrate (16) is electrically connected to the second FPC substrate (17), and a magnetoresistive sensor (171) for detecting the rotation angle of the rotor structure (1234) is electrically connected to the second FPC substrate (17).

10. The variable aperture structure based on an ultrasonic micromotor according to claim 1, characterized in that: A ring-shaped protrusion is arranged on the ultrasonic micromotor base (18), and the ultrasonic micromotor stator (15) is fixed on the ring-shaped protrusion of the ultrasonic micromotor base (18).

11. A camera module, comprising the variable aperture structure based on an ultrasonic micromotor according to any one of claims 1 to 10, characterized in that: It further includes a substrate (30), a photosensitive chip (31) is installed on the substrate (30), a lens (20) is arranged on one side of the photosensitive chip (31), and the lens (20) is located on the side of the fixed frame (19) away from the fixed disk (10).

12. The camera module according to claim 11, wherein: It further includes a housing (200), and the lens (20) is arranged in the housing (200).

13. A method for steplessly adjusting an aperture, based on the variable aperture structure of an ultrasonic micromotor according to claim 5, characterized in that: It includes the following steps: S1: sending a driving signal to the ultrasonic micromotor stator (15), which then oscillates in a circumferential direction after receiving the driving signal, and drives the rotor structure (1234) to rotate; S2: While the rotor structure (1234) rotates, the columnar structure (110) on the blade (11) is moved by the slot structure (120) to drive the blade (11) to rotate around the shaft structure (101) between the blade and the fixed disk (10).

14. The method for steplessly adjusting an aperture according to claim 13, wherein: A plurality of smooth limiting posts (191) are rotatably provided on the inner wall of the fixed frame (19); in step S1, when the rotor structure (1234) rotates, the friction layer ring (14) and the smooth limiting posts (191) are subjected to rolling friction.

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