Lens drive devices, cameras, and electronic devices

Abstract

The present invention relates to a lens driving device, a camera and an electronic device. The lens driving device includes a lens holder for fixing a lens, a first holder, a supporting assembly connected between the lens holder and the first holder, a detection assembly for detecting the position of the lens holder, and a driving assembly for driving the first holder according to an output signal of the detection assembly. The detection assembly includes a metal component embedded in the lens holder, the metal component including a metal connecting portion whose plane is substantially perpendicular to the optical axis and a plurality of metal sheets extending substantially perpendicularly from the metal connecting portion. The lens driving device of the present invention has a metal component embedded in the lens holder, and a capacitive detection assembly is formed by a component having a sheet metal layer on the plurality of metal sheets on the metal component and a fixed portion opposite to the lens holder. While achieving position detection, the radial size of the lens driving device does not increase, and miniaturization is easy to achieve and industrialization is possible.

Description

Technical Field

[0001] The present invention relates to a camera lens driving device, a camera and electronic equipment. Background Art

[0002] If a portable electronic device's camera experiences vibration or the subject's movement causes unusual light shifts during shooting, the captured image will be blurred. This is particularly noticeable in high-resolution cameras under low illumination and high-zoom conditions. The conventional approach to alleviating this blurring is to use jitter compensation technology, which detects system shake and compensates for it to improve image clarity.

[0003] Existing methods for jitter compensation include moving the lens and moving the image sensor. For example, the moving lens method utilizes a suspension system to suspend the lens in front of the image sensor, driving the lens to translate relative to the image sensor (typically within ±100 microns, equivalent to a compensating angle of ±1.5 degrees). Two Hall sensors, or a driver IC (integrated circuit) with Hall detection functionality, and corresponding sensing magnets are then used to detect the lens' position perpendicular to the optical axis. This position information, combined with closed-loop control, locks the position of the lens suspension, achieving jitter compensation.

[0004] However, the Hall element and the corresponding magnet are large in size and require a large number of connecting pins, which takes up a lot of space inside the camera and is not conducive to the miniaturization of the camera.

[0005] Currently, there are also solutions that use capacitance detection to replace Hall elements and achieve closed-loop control. For example, the Chinese invention patent "Anti-shake motor, closed-loop control method for anti-shake motor, and camera device" with patent publication number CN112235511B and publication date April 30, 2021, discloses a solution that uses the capacitance of two opposing energized electrode plates to detect the position of the anti-shake motor rotor, saving space on the position detection device. However, this solution is still imperfect and is not conducive to industrialization. Summary of the Invention

[0006] The object of the present invention is to provide an industrializable lens driving device, camera and electronic equipment that can determine the lens position by detecting capacitance values.

[0007] A lens drive device includes: a lens holder for securing a lens; a first holder; a support assembly connected between the lens holder and the first holder and allowing the lens holder to move relative to the first holder along the lens optical axis; a detection assembly for detecting the relative position of the lens holder and the first holder along the lens optical axis; and a drive assembly for driving the first holder to move along the lens optical axis based on an output signal from the detection assembly. The detection assembly includes a metal component embedded in the lens holder, the metal component comprising a metal connecting portion whose plane is substantially perpendicular to the optical axis and a plurality of metal pieces extending substantially perpendicularly from the metal connecting portion.

[0008] As an embodiment, the driving assembly includes a coil fixed on the outer peripheral side of the lens holder and a plurality of magnets fixed on the first holder; in a direction perpendicular to the optical axis, the coil and the magnet are opposed to each other in the air, and each metal sheet is also opposed to one of the plurality of magnets in the air; and in a direction perpendicular to the optical axis, the projections of the plurality of metal sheets and the coil do not overlap; regardless of whether the coil is energized or not, at least a portion of the plurality of metal sheets overlaps with the projection of the magnet in the direction perpendicular to the optical axis.

[0009] As an implementation method, it is defined that the object to be photographed is located in front of the optical axis, and the front end of the lens holder extends toward the front of the optical axis to form multiple bosses for limiting the maximum moving distance of the lens holder; the metal sheet is embedded in the bosses.

[0010] As an embodiment, the metal component further includes a conductive pin extending substantially vertically from the metal connecting portion, and the metal component is made of a non-magnetic and conductive material.

[0011] As an embodiment, a non-magnetic, conductive second metal component is also embedded in the first bracket, and the second metal component includes a first piece located in front of the optical axis direction of the multiple magnets, a second piece located on the outer peripheral side of the multiple magnets, and a third piece connecting adjacent first pieces or second pieces to make the entire second metal component ring-shaped.

[0012] As an embodiment, the support assembly includes a first leaf spring assembly, which includes four leaf springs that are not connected to each other; the inner side of each leaf spring is connected to the lens holder, and the outer side is connected to the first holder; two of the leaf springs serve as power supply paths for the coil, and at least one of the other two leaf springs serves as a power supply path for the metal component.

[0013] As an embodiment, the lens driving device also includes a base, a circuit board fixed on the base, and an upper shell snapped onto the base, and the support assembly is also used to support the first bracket to move relative to the base in a direction perpendicular to the optical axis; a plurality of second metal sheets and a plurality of anti-shake coils that constitute a second driving assembly with the plurality of magnets are formed on the circuit board; wherein each magnet is arranged opposite to at least one anti-shake coil, and the second metal sheet is arranged in front of two of the anti-shake coils in the optical axis direction, and is used to detect the movement of the first bracket in two directions perpendicular to the optical axis direction and perpendicular to each other.

[0014] As an embodiment, two second metal sheets are arranged in front of each of the two anti-shake coils, and in a direction parallel to the optical axis, the gap between the two second metal sheets is opposite to the winding hole of the anti-shake coil.

[0015] As an embodiment, a conductive path is embedded in the base, and the conductive path is electrically connected to the circuit board to realize the function of the conductive pin.

[0016] A camera includes the lens driving device as described above.

[0017] An electronic device comprises the camera described above.

[0018] The lens holder of the lens driving device of the present invention is embedded with an annular metal component, and a capacitive detection component is formed by multiple metal sheets on the metal component and a component with a sheet metal layer on the fixed part opposite to the lens holder. While realizing position detection, the radial size of the lens driving device is not increased, and miniaturization is easy to achieve and industrialization is possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 FIG. 1 is an exploded view of the lens driving device of the first embodiment.

[0020] Figure 2 for Figure 1 An exploded view of the lens mount of the center lens drive mechanism.

[0021] Figure 3 FIG. 1 is an exploded view of the lens driving device of the second embodiment.

[0022] Figure 4 for Figure 3 An exploded view of the lens mount of the center lens drive mechanism.

[0023] Figure 5 for Figure 3 The exploded picture of the first bracket.

[0024] Figure 6 Schematic diagram of the positions of the metal component, magnet and second metal component of the lens driving device in the second embodiment.

[0025] Figure 7 Schematic diagram of the structure of the magnet and the second metal sheet of the lens driving device in the second embodiment.

[0026] Figure 8 Schematic diagram of the structure of the anti-shake coil and the second metal sheet of the lens driving device in the second embodiment. DETAILED DESCRIPTION

[0027] The lens driving device, camera and electronic device of the present invention will be described in further detail below with reference to specific embodiments and accompanying drawings.

[0028] The electronic device of the present invention is an electronic device having a camera, such as, but not limited to, a mobile phone, a tablet computer, a laptop computer, a smartwatch, a fitness tracker, etc. The camera may have both focus and anti-shake functions, or may only have a focus function. The camera includes a lens drive device and an image sensor module. The lens drive device drives the lens to achieve autofocus and / or anti-shake functions, so that the image sensor module can output clear images or videos.

[0029] For ease of description, a spatial rectangular coordinate system (XYZ) is defined. The optical axis of the lens of the lens driving device of the present invention is parallel to the Z axis of the coordinate system. The subject is defined as being located in front of the lens driving device, that is, in front of the Z axis (+Z direction). In the components described below, the end / surface in the +Z direction is referred to as the front end / front surface of the component, and the end / surface in the -Z direction is referred to as the rear end / rear surface of the component.

[0030] Example 1:

[0031] Please refer to Figure 1 and Figure 2 As shown, in the first embodiment, the lens driving device of the present invention is a VCM (Voice Coil Motor) type autofocus motor, which mainly includes a lens holder 10, a first holder 20, a supporting assembly 30, a detection assembly 40 and a driving assembly 50.

[0032] The lens holder 10 serves as the movable portion of the lens drive device, securing the lens (not shown). A through hole is defined in its center for receiving the lens. The first bracket 20 serves as the fixed portion of the lens drive device. In this embodiment, it comprises a housing for the lens drive device, comprising an upper shell 21 and a base 22. The upper shell 21 engages with the base 22 to form a housing that houses the lens holder 10, support assembly 30, drive assembly 40, and detection assembly 50.

[0033] The support assembly 30 connects the lens holder 10 and the first bracket 20, suspending and supporting the lens holder 10 inside the first bracket 20, allowing the lens holder 10 to move relative to the first bracket 20 along the optical axis (Z-axis direction). In this embodiment, the support assembly 30 includes a front leaf spring 31 and rear leaf springs 32, 33, 34, and 35 (the rear leaf springs 32, 33, 34, and 35 are referred to as the first leaf spring assembly). The front leaf spring 31 includes a generally annular inner connecting portion 311 for fixed connection to the front end of the lens holder 10, a generally annular outer connecting portion 312 for fixed connection to the first bracket 20 (in this embodiment, the inner wall of the top plate of the upper housing 21), and a plurality of serpentine arms 313 extending between the inner and outer connecting portions. The serpentine structure of the arms 313 allows for elastic deformation. The rear leaf springs 32, 33, 34, and 35 are four identical leaf springs, unconnected to one another and rotationally symmetrically arranged about the optical axis. Each of these leaf springs 32, 33, 34, and 35 comprises a generally strip-shaped inner connecting portion 321 for fixed connection to the rear end of the lens holder 10, a generally strip-shaped outer connecting portion 322 for fixed connection to the first holder 20 (in this embodiment, the fixing posts 221 at the four corners of the base 22), and a serpentine arm portion 323 extending between the inner and outer connecting portions.

[0034] The drive assembly 50 is used to drive the first bracket 20 to move along the optical axis of the lens. It includes a coil 51 fixed to the outer periphery of the lens bracket 10 and a plurality of magnets 52 fixed to the first bracket 20. The coil 51 is wound around the optical axis on the outer periphery of the lens bracket 10, and the magnets 52 are fixed to the inner wall of the upper shell 21. The upper shell 21 can be made of a metal material with high magnetic permeability and electrical conductivity. In the direction perpendicular to the optical axis, the coil 51 and the magnet 52 are opposite to each other in the air. The magnet 52 is preferably made of neodymium iron boron permanent magnet (NdFeB) material, and its side facing the coil 51 is coated with a conductive metal layer 521. The conductive metal layer 521 can also be used to reduce the sensitivity of the magnet to corrosion and other negative environmental factors that may cause the magnet to degrade. In this embodiment, the surface of the magnet 52 is nickel (Ni), and this nickel plating layer also serves as one of the capacitor plates. In this embodiment, the magnet 52 is a rectangular parallelepiped, and its outer surface is coated with a conductive metal layer.

[0035] The detection assembly 40 is used to detect the relative position of the lens holder 10 and the first holder 20 in the direction of the lens optical axis. The detection assembly 40 includes a metal component 41 made of a conductive material embedded in the lens holder 10. The metal component 41 includes a metal connecting portion 411 whose plane is substantially perpendicular to the optical axis (Z axis) and a plurality of metal sheets 412 extending substantially perpendicularly from the periphery of the metal connecting portion 411. The plurality of metal sheets 412 serve as two of the capacitor plates. Each metal sheet 412 is spaced apart from one of the plurality of magnets 52. Regardless of whether the coil is energized or not, at least a portion of the plurality of metal sheets 412 overlaps with the projection of the magnet 52 in a direction perpendicular to the optical axis. As the lens holder 10 moves (during the autofocus process), the area of overlap changes regularly.

[0036] The metal sheet 412 of the metal component 41 and the conductive metal layer 521 of the magnet 52 form a capacitor. When the drive component 50 drives the lens holder 10 to move along the optical axis with the lens, the overlapping area of the projections of the metal sheet 412 and the magnet 52 in the direction perpendicular to the optical axis changes accordingly, and the corresponding capacitance value changes accordingly. Therefore, the drive component 50 can calculate the corresponding capacitance value based on the output signal of the detection component 40, and drive the first bracket 10 to move a distance along the optical axis of the lens according to the capacitance value, thereby realizing closed-loop control and more precise control. The lens holder 10 is made of a non-conductive material, preferably a plastic material. The metal component 41 can be embedded in the lens holder 10 by injection molding, which is easy to industrialize. Moreover, the metal component 41 only includes a metal connecting portion 411 and a metal sheet 412, which can be made very light and thin. While realizing position detection, the radial size of the lens drive device is not increased, and miniaturization is easy to achieve. The metal connection portion 411 serves as a conductive path for the multiple metal sheets 412 and facilitates the integrated manufacturing of the metal component 41 . There is no need to consider the positioning of the multiple metal sheets 412 during assembly, thus facilitating automated production and assembly.

[0037] In this embodiment, the metal connecting portion 411 is preferably a sheet-shaped ring. Furthermore, preferably, when viewed from the optical axis, the metal component 41 is substantially rotationally symmetrical, comprising four metal sheets 412. This ensures that the presence of the metal component 41 does not affect the balance of the lens holder. In a direction perpendicular to the optical axis, the coil 51 is not positioned between the conductive metal layer 521 and the metal sheet 412. The metal component 41 is preferably made of a conductive, non-magnetic material, such as copper or stainless steel, to prevent the movement of the movable portion from being affected by the attraction of the magnet.

[0038] A conductive pin 413 may also extend substantially vertically from the metal connection portion 411. The distal end of the conductive pin 413 is exposed from the surface of the lens holder 10 for convenient electrical connection.

[0039] In this embodiment, four rear leaf springs 32, 33, 34, and 35 are used as a conductive path between the coil 51 and the metal component 41. Two of the rear leaf springs, such as but not limited to 32 and 34, provide power to the coil 51 in the movable portion, while one of the other two rear leaf springs provides electrical power to the metal component 41 in the movable portion. Thus, the rear leaf springs 32, 33, 34, and 35 are all made of conductive metal, such as copper. The front leaf spring 31 can be made of either metal or elastic plastic. The outer connecting portions 322 of the rear leaf springs 32, 33, 34, and 35 are connected to a power supply circuit located on one side of the base 22, such as the circuit board 222 or conductive pins located on the base 22. The conductive metal layer 521 of the magnet 52 can be directly connected to the power supply circuit on one side of the base 22, such as the circuit board 22 or the conductive pin located on the base 22, and preferably, the metal layers 521 of multiple magnets 52 are connected in series through the upper shell 21, so that the capacitance value on one side of the magnet 52 is the sum of the capacitance values generated by the multiple metal layers 521.

[0040] In other embodiments, the upper shell may be made of a non-conductive material, in which case a conductive magnetic sheet may be added to enhance the internal magnetic field and achieve the conductive function. Alternatively, the conductive metal layer 521 may be energized directly using a wire.

[0041] In the above embodiment, the conductive metal layer 521 of all magnets 52 is used as one of the electrode plates of the capacitive detection component 40, and the multiple metal sheets 412 as a whole serve as the other electrode plate. This makes the capacitance value output by the detection component 40 larger, the detection sensitivity higher, and the lens drive device structure more concise, the circuit layout is simpler, the number of conductive pins is reduced, and it is easier to industrialize. It is understandable that in other embodiments, a conductive metal sheet can be set at a position not covered by the magnet 52 on the inner wall of the upper shell 21, such as at or near the four corners, to serve as an electrode plate of the capacitor, forming a position detection capacitor with the metal component 41, which can also achieve the function of the detection component 40. Alternatively, a metal sheet can be attached to the side of the magnet 52 facing the coil 51 as an electrode plate of the capacitor, such as a square basket-shaped metal sheet that only covers the four sides of the side of the magnet 52 facing the coil 51, thereby achieving precise closed-loop control without affecting the driving force of the lens drive device.

[0042] In the first embodiment, multiple bosses 11 extend from the front end of the lens holder 10, toward the front of the optical axis, to limit the maximum forward movement of the lens holder 10. The metal sheet 412 of the metal component 41 is embedded within the bosses 11. This clever use of the space provided by the position-limiting bosses 11 allows the area of the metal sheet 412 to be increased without increasing the size of the lens holder 10.

[0043] In the first embodiment, the lens driving device is a VCM motor, that is, the driving component is a motor that uses a powered coil and a magnet to generate driving force. It is understood that in variations of the first embodiment, the lens driving device can be a piezoelectric motor or a memory alloy motor.

[0044] In a piezoelectric motor, ultrasonic piezoelectric ceramics are used as the driving component. One end of the piezoelectric ceramic component is connected to the lens holder, which serves as the movable portion, and the other end is connected to the housing, which serves as the first support. A conductive sheet, serving as the other electrode plate of the capacitor, can be disposed on the inner wall of the housing, facing the metal sheet 412 in space. The relative area between the two can be regularly changed during the autofocus process. In this way, the position of the lens holder can be determined based on the change in the capacitance value of the capacitor formed by the two.

[0045] In a memory alloy motor, the deformation characteristics of the memory alloy when the temperature changes after power is applied are used to generate driving force. The lens holder is supported within the housing via a memory alloy suspension. The conductive sheet, serving as the other electrode plate of the capacitor, can be placed on the inner wall of the housing or at another location spaced apart from the metal sheet 412. As long as the relative area between the two changes regularly during the autofocus process, the position of the lens holder can be determined based on the changes in the capacitance value of the capacitor formed by the two.

[0046] In the first embodiment, the lens driving device uses a leaf spring as a supporting component. It is understood that in a variation of the first embodiment, a ball bearing and groove assembly may be used to replace the leaf spring.

[0047] Example 2:

[0048] Please refer to Figure 3 and Figure 8 As shown, in the second embodiment, the lens driving device of the present invention is a VCM (Voice Coil Motor) type OIS (Optical Image Stabilization) motor, which mainly includes an autofocus module and an anti-shake module.

[0049] Among them, the autofocus module includes the same lens holder 10, detection assembly 40 and drive assembly 50 as the lens holder 10, detection assembly 40 and drive assembly 50 in Example 1, so the same reference numerals are used to represent them, and the shapes and structures of these components are not described in detail. The first bracket 20' of the autofocus module of Example 2 is a magnet bracket for fixing the magnet 52. The upper shell 21 and base 22 of the lens drive device no longer serve as the first bracket, but only as the shell of the lens drive device, and are basically the same as the upper shell and base structure in Example 1, but the upper shell here is made of non-magnetic metal material, so the same reference numerals are used and they are not described in detail.

[0050] The support assembly 30', used to suspend and support the lens holder 10 on the inner periphery of the first bracket 20', includes a front spring member 32' and a rear spring member 31'. The rear spring member 31' is a single-piece leaf spring, similar in structure to the front leaf spring 31 in the first embodiment. Both comprise a substantially annular inner connecting portion 311 for fixed connection to the rear end of the lens holder 10, a substantially annular outer connecting portion 312 for fixed connection to the rear end of the first bracket 20, and a plurality of serpentine arms 313 connected between the inner and outer connecting portions. The serpentine structure of the arms 313 allows for elastic deformation. The front spring member 32' includes front leaf springs 32', 33', 34', and 35', similar to the rear leaf springs 32, 33, 34, and 35 in the first embodiment, and a linear spring 36 (the front leaf springs 32', 33', 34', 35' and the linear spring 36 constitute the first leaf spring assembly). The front leaf springs 32', 33', 34', and 35' are identical in structure, unconnected, and rotationally symmetrically arranged about the optical axis. Each of the front leaf springs 32', 33', 34', and 35' comprises a substantially strip-shaped inner connecting portion 321 for fixed connection to the front end of the lens holder 10, a substantially strip-shaped outer connecting portion 322 for fixed connection to the front end of the first bracket 20, and a serpentine arm portion 323 extending between the inner and outer connecting portions. The front leaf springs 32', 33', 34', and 35' and the rear spring member 31' suspend the lens holder 10 on the inner circumference of the first bracket 20' and allow the lens holder 10 to move relative to the first bracket 20' along the optical axis.

[0051] The upper ends of four linear springs 36 are connected to the outer connecting portions 322 of the front leaf springs 32', 33', 34', and 35' via four cantilever arms 37, and their lower ends are connected to the four corners of the base 22. The linear springs 36 suspend the first bracket 20' within the housing and allow it to move relative to the base in a direction perpendicular to the optical axis (Z axis).

[0052] The first bracket 20' is generally in the form of a square basket, and the magnet 52 is fixed to the inner side wall of the first bracket 20'. In a direction perpendicular to the optical axis, the coil 51 and the magnet 52 are spaced apart and opposite each other. The magnet 52 is preferably made of neodymium iron boron permanent magnet (NdFeB) material with a high magnetic energy product, and the side facing the coil 51 is plated with a conductive metal layer 521. The conductive metal layer 521 can also be used to reduce the sensitivity of the magnet to corrosion and other negative environmental factors that may degrade the magnet. In the present embodiment, the magnet 52 is in the form of a rectangular parallelepiped, and its outer surface is plated with a conductive metal layer. In the present embodiment, the surface of the magnet is plated with a nickel (Ni) layer. This nickel-plated layer also serves as one of the capacitor plates.

[0053] The metal component 41 embedded in the lens holder 10 is identical to that in the first embodiment and comprises a metal connection portion 411 whose plane is substantially perpendicular to the optical axis (Z-axis) and a plurality of metal pieces 412 extending substantially perpendicularly from the periphery of the metal connection portion 411. Each metal piece 412 is spaced apart from one of the magnets 52. Regardless of whether the coil is energized or not, at least a portion of the metal pieces 412 overlaps with the projection of the magnet 52 in a direction perpendicular to the optical axis. The area of overlap changes as the lens holder 10 moves.

[0054] The metal sheet 412 of the metal component 41 and the conductive metal layer 521 of the magnet 52 form a capacitor. When the drive component 50 drives the lens holder 10 to move along the optical axis with the lens, the overlapping area of the projections of the metal sheet 412 and the magnet 52 in the direction perpendicular to the optical axis changes accordingly, and the corresponding capacitance value changes accordingly. Therefore, the drive component 50 can calculate the corresponding capacitance value based on the output signal of the detection component 40, and drive the first bracket 10 to move a distance along the optical axis of the lens according to the capacitance value, thereby realizing closed-loop control and more precise control. The lens holder 10 is made of a non-conductive material, preferably a plastic material. The metal component 41 can be embedded in the lens holder 10 by injection molding, which is easy to industrialize. Moreover, the metal component 41 only includes a metal connecting portion 411 and a metal sheet 412, which can be made very light and thin. While realizing position detection, the radial size of the lens drive device is not increased, and miniaturization is easy to achieve. The metal connector 411 serves as a conductive path for the multiple metal sheets 412, facilitating the integrated manufacturing of the metal component 41. There is no need to consider the positioning of the multiple metal sheets 412 during assembly, facilitating automated production and assembly. Furthermore, the conductive metal layer 521 and the metal sheets 412, which serve as the electrode plates of the capacitive detection component 40 and are electroplated nickel (Ni) on the surface of the magnet 52 and also serve as a protective layer, result in a larger capacitance value output by the detection component 40, resulting in higher detection sensitivity. Furthermore, the lens drive device has a simpler structure, a simpler circuit layout, and is more easily industrialized.

[0055] Furthermore, as in the first embodiment, the metal connecting portion 411 is preferably annular and sheet-shaped. Viewed from the optical axis, the metal component 41 is essentially rotationally symmetrical and comprises four metal plates 412. This ensures that the presence of the metal component 41 does not affect the balance of the lens holder. In a direction perpendicular to the optical axis, the coil 51 is not positioned between the conductive metal layer 521 and the metal plates 412. The metal component 41 is preferably made of a conductive, non-magnetic material, such as copper or stainless steel. A conductive pin 413 may also extend substantially perpendicularly from the metal connecting portion 411. The distal end of the conductive pin 413 is exposed from the surface of the lens holder 10 to facilitate electrical connection. Multiple bosses 11 extend from the front end of the lens holder 10, toward the front of the optical axis, to limit the maximum forward travel distance of the lens holder 10. The metal plates 412 of the metal component 41 are embedded within the bosses 11. By cleverly utilizing the space provided by the position-limiting bosses 11, the area of the metal plates 412 can be increased without increasing the size of the lens holder 10.

[0056] Furthermore, a second, magnetically and electrically conductive, metal component 23 is embedded within the first bracket 20'. This component acts as a magnetically conductive iron to increase magnetic force. The second metal component 23 is also electrically conductive and serves to supply power to the metal layer 521 of the magnet 52. The second metal component 23 primarily comprises a first piece 231 positioned in front of the optical axis of the multiple magnets 52, a second piece 232 positioned on the outer periphery of the multiple magnets 52, and a third piece 233 connecting adjacent first pieces 231 or second pieces 232 to form the entire second metal component 23 in a ring-shaped configuration. Furthermore, multiple holes are formed in the second metal component 23 to reduce the weight of the movable portion.

[0057] In this embodiment, four linear springs 36, four cantilevers 37, and four front leaf springs 32', 33', 34', and 35' are used as the conductive path for the coil 51 (2-pin), the metal component 41 (1-pin), and the metal layer 521 (1-pin) of the magnet 52, with a total of 4 pins of power lines. Two of the front leaf springs, such as but not limited to 32' and 34' and the corresponding cantilevers 37 and linear springs 36, supply power to the coil 51, while the other two front leaf springs and the corresponding cantilevers and linear springs supply power to the metal component 41 and the metal layer 521 of the magnet 52, respectively. Thus, the front spring component 32' is made of conductive metal, such as copper. The rear leaf spring 31' can be made of metal or elastic plastic. The four magnets 52 and the metal component 41 form a large-capacity capacitor, which serves as the electrode plate of the capacitive detection component 40, so that the capacitance value output by the detection component 40 is large and the detection sensitivity is high. The end of the linear spring 36 may be connected to a power supply circuit located on one side of the base 22 , such as a circuit board 222 ′ or a conductive pin located on the base 22 .

[0058] It is understood that in other modified embodiments, conductive metal sheets can be placed on the inner wall of the first bracket 20' at locations not covered by the magnet 52, such as at or near the four corners, to serve as capacitor electrode plates, forming a position detection capacitor with the metal component 41, thereby similarly achieving the function of the detection assembly 40. Alternatively, a metal sheet can be attached to the side of the magnet 52 facing the coil 51 to serve as a capacitor electrode plate, such as a square basket-shaped metal sheet that only covers the four sides of the side of the magnet 52 facing the coil 51. This allows precise closed-loop control to be achieved without affecting the driving force of the lens driving device.

[0059] In the second embodiment, a circuit board 222' on the base 22 is formed with multiple second metal sheets 2221 and multiple anti-shake coils 2222, which together with multiple magnets 52 form a second drive assembly. The anti-shake coils 2222 are wound parallel to the Z-axis, and each anti-shake coil 222 is spaced opposite the rear end of a magnet 52 in the Z-axis direction. When the anti-shake coils 2222 are energized, the Lorentz force generated in the magnetic field propels the first bracket 20' and the lens to move in the X-axis and / or Y-axis directions, thereby compensating for vibration in the corresponding directions and achieving the anti-shake function.

[0060] A conductive metal layer 522 is also formed on the rear end surface of the magnet 52. The second metal sheet 2221 (here, two independent capacitor plates) and the conductive metal layer 522 of the magnet 52 form two capacitors. When the first bracket 20' of the second drive component drives the lens bracket 10 and then moves the lens in a direction perpendicular to the optical axis, the overlapping area of the projection of the second metal sheet 2221 and the conductive metal layer 522 at the bottom of the magnet 52 in a direction parallel to the optical axis changes accordingly, and the corresponding capacitance value changes accordingly. The second drive component can thus drive the first bracket 20' to move a distance perpendicular to the optical axis of the lens based on the changing capacitance value, achieving closed-loop control and more precise control. The second metal sheet 2221 can be a conductive metal layer etched on the circuit board 222', or it can be a metal sheet welded to the circuit board 222'. It can be made very light and thin, and while achieving position detection, it basically does not increase the size of the circuit board, making it easy to achieve a light and thin circuit board. In addition, the electroplated metal nickel (Ni) layer on the surface of the magnet 52, which also serves as a protective layer, the conductive metal layer 522 is used as the electrode plate of the capacitive detection component, so that the capacitance value output by the detection component can be differentially compensated, the detection sensitivity is high, and the lens driving device structure is simpler, the circuit layout is simpler, and it is easier to industrialize.

[0061] In this embodiment, the metal layers 521 and 522 of magnet 52 serve as capacitor plates in three axes (optical axis / Z axis, X axis, and Y axis), significantly reducing the number of conductive pins. Metal layers 521 and 522 serve as the capacitor's emitter, while metal sheet 412 and second metal sheet 2221 serve as the capacitor's receiver. The emitters can be connected in series and then share a common ground, reducing the number of pins.

[0062] In this embodiment, only one pair of second metal sheets 2221 is arranged in the X-axis and Y-axis directions. The second metal sheets in each pair 2221 are arranged side by side and respectively face the two long sides (coil bodies) of an anti-shake coil 2222. The gap between the two second metal sheets 2221 faces the winding hole of the anti-shake coil 2222. The advantage of using two sets of capacitors is that they can be used differentially, effectively compensating for changes in dielectric constant or capacitor plate spacing caused by reliability, temperature, and humidity.

[0063] Observed along the Z-axis, at least a portion of one of the second metal sheets 2221 in each pair overlaps with the projection of the magnet 52 in a direction perpendicular to the optical axis. Therefore, no matter how the magnet 52 moves along its length, the area directly facing the second metal sheet 2221 remains unchanged. Therefore, only when the magnet 52 moves along its width does the area directly facing each second metal sheet 2221 change regularly.

[0064] That is, when the first bracket 20' moves in the X-axis (Y-axis) direction, the area of the second metal sheet 2221 located in the X-axis (Y-axis) direction that faces the conductive metal layer 522 of the magnet 52 changes regularly, thereby determining the distance the first bracket 20' has translated relative to the base 22 in the X-axis (Y-axis) direction based on the changing capacitance value. Meanwhile, the area of the second metal sheet 2221 located in the Y-axis (X-axis) direction that faces the corresponding magnet does not change. The specific direction of movement (+X-axis direction or -X-axis direction) can be determined by whether the capacitance between one of the pair of second metal sheets 2221 and the magnet increases or decreases.

[0065] In this embodiment, the circuit board 222' is a multi-layer circuit board, with the second metal sheet 2221 and the anti-shake coil 2222 integrally formed on the circuit board 222'. The second metal sheet 2221 is formed on the topmost layer of the circuit board 222', while the anti-shake coil 2222 occupies a middle layer of the circuit board 222'. For example, a three-, four-, or five-layer coil may be provided depending on the desired thrust. The bottom layer of the circuit board 222' may be an electrical signal circuit layer, allowing control circuits such as the capacitor control circuit, the drive component, and the driver chip of the second drive component to be soldered to the bottom surface of the circuit board 222'.

[0066] Furthermore, conductive paths are embedded within the base 22. These paths electrically connect to the circuit board, functioning as conductive leads for the circuit board. This allows the conductive pins of the entire lens actuator to extend from the back or side of the base 22, further minimizing the space occupied by the electrical connections. This also reduces the number of parts on one side of the base, simplifying assembly, improving assembly efficiency and yield, and facilitating industrialization. In this embodiment, the ends of the linear spring 36 are inserted into holes at the four corners of the base 22, connecting to the conductive paths within the base, ensuring the stability of the bottom of the linear spring 36.

[0067] In the description of the present invention, it should be understood that terms such as "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0068] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of the technical features being referenced. Thus, a feature identified with "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0069] In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connect," "fixed," etc. should be understood broadly. For example, they may refer to fixed connection, detachable connection, or integration; mechanical connection or electrical connection; direct connection or indirect connection through an intermediate medium; internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0070] Although the present invention has been described with reference to the above specific embodiments, it will be apparent to those skilled in the art that many substitutions, modifications, and variations can be made based on the above. Therefore, all such substitutions, modifications, and variations are intended to be encompassed within the spirit and scope of the appended claims.

Claims

1. A lens driving device, wherein a subject is defined to be located in front of an optical axis, the lens driving device comprising: A lens holder for fixing the lens, wherein a plurality of bosses extend from its front end toward the front of the optical axis and are used to limit the maximum movement distance of the lens holder; First bracket; A support assembly connected between the lens holder and the first holder and allowing the lens holder to move relative to the first holder along the lens optical axis; A detection component for detecting the relative positions of the lens holder and the first holder in the direction of the lens optical axis; as well as a driving assembly for driving the first bracket to move along the lens optical axis according to the output signal of the detection assembly, comprising a coil fixed to the outer periphery of the lens bracket and a plurality of magnets fixed to the first bracket; Its characteristics are: The detection assembly includes a metal component embedded in the lens holder, the metal component including a metal connecting portion whose plane is substantially perpendicular to the optical axis and a plurality of metal sheets extending substantially perpendicularly from the metal connecting portion; In a direction perpendicular to the optical axis, the coil and the magnet are opposed to each other in the air, and each metal sheet is also opposed to one of the multiple magnets in the air; and in a direction perpendicular to the optical axis, the projections of the multiple metal sheets and the coil do not overlap; regardless of whether the coil is energized or not, at least a portion of the multiple metal sheets overlaps with the projection of the magnet in the direction perpendicular to the optical axis.

2. The lens driving device according to claim 1, wherein: The metal sheet is embedded in the boss.

3. The lens driving device according to claim 1, wherein: The metal component further includes a conductive pin extending substantially vertically from the metal connecting portion, and the metal component is made of a non-magnetic and conductive material.

4. The lens driving device according to claim 1, wherein: A non-magnetic, conductive second metal component is also embedded in the first bracket. The second metal component includes a first piece located in front of the optical axis direction of the multiple magnets, a second piece located on the outer peripheral side of the multiple magnets, and a third piece that connects adjacent first pieces or second pieces to make the entire second metal component ring-shaped.

5. The lens driving device according to claim 1, wherein: The support assembly includes a first leaf spring assembly, which includes four leaf springs that are not connected to each other; the inner side of each leaf spring is connected to the lens holder, and the outer side is connected to the first holder; two of the leaf springs serve as power supply paths for the coil, and at least one of the other two leaf springs serves as a power supply path for the metal component.

6. The lens driving device according to claim 1, wherein: It also includes a base, a circuit board fixed on the base, and an upper shell snapped on the base, and the support assembly is also used to support the first bracket to move relative to the base in a direction perpendicular to the optical axis; a plurality of second metal sheets and a plurality of anti-shake coils that constitute a second driving assembly with the plurality of magnets are formed on the circuit board; wherein each magnet is arranged opposite to at least one anti-shake coil, and the second metal sheet is arranged in front of two of the anti-shake coils in the optical axis direction, and is used to detect the movement amount of the first bracket in two directions perpendicular to the optical axis and perpendicular to each other.

7. The lens driving device according to claim 6, wherein: Two second metal sheets are arranged in front of each of the two anti-shake coils, and in a direction parallel to the optical axis, the gap between the two second metal sheets is opposite to the winding hole of the anti-shake coil.

8. The lens driving device according to claim 6, wherein: The base is embedded with a conductive path, and the conductive path is electrically connected to the circuit board to realize the function of the conductive pin.

9. A camera, characterized in that: The lens driving device comprises the lens driving device according to any one of claims 1 to 8.

10. An electronic device, characterized in that: Comprising the camera of claim 9.

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