CN117369076A - Lens driving device, camera equipment and intelligent terminal - Google Patents

Abstract

The application provides a lens driving device, which comprises a stator assembly and a rotor assembly, wherein the stator assembly and the rotor assembly are connected in a relatively movable manner; one of the stator assembly and the sub-assembly comprises a laser ranging device, the other one comprises a reflecting structure corresponding to the laser ranging device, the laser ranging device is used for sending laser signals to the reflecting structure, the reflecting structure is used for reflecting the laser signals back to the laser ranging device, so that the distance between the stator assembly and the sub-assembly is detected in a laser ranging mode, and the displacement of the sub-assembly relative to the stator assembly is determined according to the distance. The application also provides image pickup equipment and an intelligent terminal with the lens driving device.

Description

Lens driving device, camera equipment and intelligent terminal

Technical Field

The application belongs to the technical field of image pickup, and particularly relates to a lens driving device for image pickup equipment, and image pickup equipment and an intelligent terminal with the lens driving device.

Background

In order to improve the quality of photographed pictures, existing image pickup apparatuses widely optically compensate for shake of the image pickup apparatus during photographing by a lens driving device. The lens driving apparatus generally includes a stator assembly fixed in the image pickup device and a sub-assembly movable with respect to the stator assembly, in which the lens assembly of the image pickup device may be mounted. When the image pickup device works, the lens driving device can detect the offset of the lens assembly caused by the shake of the image pickup device, and control the sub-assembly to drive the lens assembly or the image sensor to correspondingly move so as to compensate the offset of the lens assembly, thereby eliminating imaging blurring caused by the shake of the image pickup device.

In the above anti-shake scheme, a hall element is generally used to detect the position information of the lens assembly in real time, so as to be used as a reference basis for controlling the movement of the sub-assembly. The specific technical means is that a Hall element is arranged in one of a stator component and a rotor component, and a magnet is arranged in the other stator component and rotor component (the magnet can be used for enabling a coil to generate electromagnetic thrust for controlling the rotor component to move in a magnetic field); when the camera shooting equipment shakes, the rotor component can move relative to the stator component, so that the Hall element moves relative to the magnet, the Hall element senses the change of the magnetic field at the moment, and then the corresponding induced electromotive force is changed, and the direction and the amplitude of the displacement of the lens component relative to the stator component under the shaking condition can be determined according to the magnitude and the change mode of the induced electromotive force.

However, the above-described solution using hall elements also has some drawbacks, such as: (1) The Hall element needs to generate induced electromotive force based on magnetic field change as a detection signal reflecting the position of the lens assembly, and the precision of the detection mode is often not ideal enough and is easily interfered by an external electromagnetic field; (2) Providing a hall element in an image pickup apparatus increases manufacturing costs; (3) The Hall element can generate certain electromagnetic interference to other electronic devices of the camera equipment; (4) The hall element occupies more assembly space in the camera device, and at the same time, enough movement space must be reserved for the sub-assembly in the camera device; both aspects need to design more internal reserved spaces in the image pickup equipment, which is not only unfavorable for miniaturization of products, but also leads to difficult arrangement of a dustproof structure in the image pickup equipment and easy pollution of impurities such as dust entering from the outside.

Therefore, there is a need to provide a lens driving device with a more novel structure, and an image capturing apparatus and an intelligent terminal having the lens driving device, so as to solve the above-mentioned drawbacks of the existing lens driving device.

Disclosure of Invention

Based on the above-mentioned problems in the prior art, an object of the present application is to provide a lens driving device with more novel structure and working principle, and an image capturing apparatus and an intelligent terminal having the lens driving device, so as to solve the above-mentioned problems caused by using hall elements in the existing lens driving device.

In order to solve the above problems, an embodiment of an aspect of the present application provides a lens driving device, including a stator assembly and a mover assembly, where the stator assembly and the mover assembly are relatively movably connected; one of the stator assembly and the sub-assembly comprises a laser ranging device, the other one comprises a reflecting structure corresponding to the laser ranging device, the laser ranging device is used for sending laser signals to the reflecting structure, the reflecting structure is used for reflecting the laser signals back to the laser ranging device, so that the distance between the stator assembly and the sub-assembly is detected in a laser ranging mode, and the displacement of the sub-assembly relative to the stator assembly is determined according to the distance.

In some embodiments, the laser ranging device comprises a first laser ranging device, a second laser ranging device, and a third laser ranging device, the reflective structure comprises a first reflective structure, a second reflective structure, and a third reflective structure; the first laser ranging device and the first reflecting structure are used for detecting displacement of the sub-assembly relative to the stator assembly in a first direction, the second laser ranging device and the second reflecting structure are used for detecting displacement of the sub-assembly relative to the stator assembly in a second direction, the third laser ranging device and the third reflecting structure are used for detecting displacement of the sub-assembly relative to the stator assembly in a third direction, and the first direction, the second direction and the third direction are mutually perpendicular.

In some embodiments, the number of third laser ranging devices and third reflecting structures is a plurality, the plurality of third laser ranging devices and third reflecting structures being configured to simultaneously detect displacement of the plurality of positions of the sub-assembly in the third direction relative to the stator assembly to detect angular deflection of the sub-assembly in the third direction relative to the stator assembly.

In some embodiments, the stator assembly further comprises a coil carrier and a focusing coil, the first laser ranging device, the second laser ranging device, and the focusing coil being mounted on the coil carrier; the sub-assembly further comprises a lens carrier and a magnet arranged on the lens carrier, and the first reflecting structure and the second reflecting structure are formed on the lens carrier; the focusing coil and the magnet are used for generating first electromagnetic thrust to drive the sub-assembly to focus.

In some embodiments, the lens carrier is sleeved inside the coil carrier, the first laser ranging device, the second laser ranging device and the focusing coil are all mounted on the inner surface of the coil carrier, and the first reflecting structure and the second reflecting structure are all formed on the outer surface of the lens carrier and aligned with the first laser ranging device and the second laser ranging device respectively.

In some embodiments, the lens driving device further includes a spring assembly having elasticity and connecting the lens carrier and the coil carrier to be movable relatively.

In some embodiments, the stator assembly further comprises a circuit board, the third laser ranging device is disposed on the circuit board, and the third reflective structure is formed on the lens carrier and aligned with the third laser ranging device; the circuit board comprises an anti-shake coil, and the anti-shake coil and the magnet are used for generating second electromagnetic thrust to drive the rotor assembly to perform optical anti-shake.

In some embodiments, the third laser ranging device and the anti-shake coil are disposed on two opposite surfaces of the circuit board, respectively.

An embodiment of another aspect of the present application further provides an image capturing apparatus, including a lens assembly, an image sensor assembly, and a lens driving device as described above, where the lens assembly is installed in the sub-assembly of the lens driving device, and the image sensor assembly is configured to acquire an optical signal captured by the lens assembly to perform imaging.

An embodiment of another aspect of the present application further provides an intelligent terminal, including the aforementioned image capturing apparatus.

Compared with the prior art, the lens driving device, the imaging equipment with the lens driving device and the intelligent terminal provided by the preferred embodiment replace the traditional Hall element by the technical means of laser ranging to detect the displacement of the sub-component of the lens driving device and the lens component arranged in the sub-component relative to the stator component, so that the lens driving device, the imaging equipment with the lens driving device and the intelligent terminal are used as reference bases for controlling the sub-component to perform position compensation in AF operation and OIS operation. Because the Hall element is not used in the technical scheme, the rotor component and the lens component are not subjected to external electromagnetic interference when being subjected to position detection, and electromagnetic interference is not generated at the same time; and the laser ranging technical means that this application's technical scheme used compares with hall element, and response that distance detected is faster, the precision is higher, and manufacturing cost is lower, also saves assembly space more.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and that other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is an exploded view of a lens driving device according to a preferred embodiment of the present application.

Fig. 2 is a schematic diagram of an assembled lens driving apparatus shown in fig. 1.

Fig. 3 is a schematic sectional view of the lens driving apparatus shown in fig. 2 along the A-A direction shown in fig. 2.

Fig. 4 is a schematic sectional view of the lens driving apparatus shown in fig. 2 along the B-B direction shown in fig. 2.

Fig. 5 is a schematic sectional view of the lens driving apparatus shown in fig. 2 along the direction C-C shown in fig. 2.

Fig. 6 is a schematic sectional view of the lens driving apparatus shown in fig. 2 along the D-D direction shown in fig. 2.

Fig. 7 is a schematic view of the structure of the bottom surface of the lens carrier in the lens driving apparatus shown in fig. 1 and 2.

Fig. 8 is a schematic diagram of the top surface of the circuit board in the lens driving apparatus shown in fig. 1 and 2.

Fig. 9 is a schematic diagram of the bottom surface of the circuit board in the lens driving apparatus shown in fig. 1 and 2.

Fig. 10 is a schematic diagram of an optical principle in the case of ranging using a laser in the lens device shown in fig. 2.

Fig. 11 is a schematic view of a laser light path when ranging is performed using a laser light in the lens device shown in fig. 2.

Detailed Description

Specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by those of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

The present invention provides a lens driving device with more novel structure and working principle, an image pickup apparatus and an intelligent terminal with the lens driving device, so as to solve various problems caused by detecting the position of a lens assembly by using a hall element in the existing lens driving device, such as unsatisfactory precision, easy electromagnetic interference, high cost, large occupied space, and unfavorable design of a dust-proof structure.

Referring first to fig. 1, 2, 3 and 4, a preferred embodiment of the present application provides a lens driving device that may be used in an image capturing apparatus to provide Auto Focus (AF) and optical anti-shake (Optical Image Stablization, OIS) functions for an existing lens assembly (not shown). The lens driving device may include a housing 1, a spring assembly 2, a lens carrier 3, a magnet 4, a coil carrier 5, a coil 6, a first laser ranging device 7, a second laser ranging device 8, a circuit board 9, and a base 10.

The shape of the housing 1 is preferably a rectangular box body, comprising a housing top plate 1a with a basically rectangular flat plate shape and four housing side plates 1b with a basically rectangular flat plate shape, wherein a lens hole 1c for extending a lens component is formed in the middle of the housing top plate 1a, the four housing side plates 1b are all connected with the housing top plate 1a perpendicularly at the edge of the same surface of the housing top plate 1a, and the four housing side plates 1b are connected end to enclose a rectangular frame body. The housing 1 is used to house other components of the lens driving apparatus therein to protect the internal components of the lens driving apparatus and to form an integrated overall structure.

The spring assembly 2 in this embodiment includes two upper springs 21 and two lower springs 22, and the upper springs 21 and the lower springs 22 are both substantially semi-annular in shape. Two upper spring plates 21 may be fixed to the top of the lens carrier 3 (described in detail below) and enclose a ring-shaped structure around the top surface of the lens carrier 3, and two lower spring plates 22 may be fixed to the bottom of the lens carrier 3 and enclose a ring-shaped structure around the bottom surface of the lens carrier 3. The middle of each upper dome 21 is formed with an upper dome extension 23 extending outward, and the upper dome extension 23 is used for being connected to the top of a coil carrier 5 (described in detail below) to connect the lens carrier 3 and the coil carrier 5 to each other; a lower dome extension 24 extending outward is formed at a middle portion of each lower dome 22, and the lower dome extension 24 is used to be connected to a bottom portion of the coil carrier 5 to interconnect the lens carrier 3 and the coil carrier 5. The upper spring plate 21 and the lower spring plate 22 may be made of elastic materials, such as metal, rubber, plastic, etc., so that after the lens carrier 3 is connected with the coil carrier 5 through the upper spring plate 21 and the lower spring plate 22, if the lens carrier 3 is shifted relative to the coil carrier 5 under the influence of an external force, after the external force is eliminated, the upper spring plate 21 and the lower spring plate 22 can utilize their own elasticity to generate a restoring force to eliminate the shift of the position of the lens carrier 3. In the present embodiment, the upper spring plate 21 and the lower spring plate 22 are preferably made of conductive elastic materials, such as metal materials, so that the spring plate assembly 2 can be used to provide an elastic restoring force for the lens carrier 3, and at the same time, can be used to provide an electrical connection path between the lens carrier 3 and the coil carrier 5. It will be appreciated that in other embodiments, the specific number of the upper spring plate 21 and the lower spring plate 22 is not limited to two, and the shape is not limited to a semi-annular shape, as long as the above-mentioned connection function can be achieved; the spring assembly 2 may also include only the upper spring 21 or only the lower spring 22.

The lens carrier 3 may be substantially cylindrical or hollow prismatic in shape, for example, the lens carrier 3 in this embodiment has a hollow quadrangular prism shape with four corners cut off, and a mounting hole 30 for mounting a lens assembly is formed in the middle thereof. The lens carrier 3 has an outer dimension smaller than an inner dimension of the housing 1, can be sleeved inside the housing 1, and is movably connected with the housing 1 through an upper spring plate assembly 2 and a lower spring plate assembly 7 (described in detail below). When the lens carrier 3 is fitted inside the housing 1, the mounting hole 30 thereof may be aligned with the lens hole 1c formed in the housing top plate 1a of the housing 1, so that the lens assembly mounted in the mounting hole 30 may be protruded from the housing 1 through the lens hole 1c to take an image. The structural features of the lens assembly for mounting in the mounting hole 30 of the lens carrier 3 may all be referred to in the prior art, and need not be described here in detail. The exterior of the lens carrier 3 is also provided with a magnet accommodating groove 32 for accommodating the magnet 4, and the magnet accommodating groove 32 is preferably an annular groove formed by partially recessing the outer surface of the lens carrier 3.

Referring to fig. 5, a first reflecting structure 31 and a second reflecting structure 33 are further formed on the outer surface of the lens carrier 3. In the present embodiment, the first reflecting structure 31 and the second reflecting structure 33 are each a groove recessed from the outer surface of the lens carrier 3, and the first reflecting structure 31 and the second reflecting structure 33 are symmetrically disposed at two opposite corner positions of the lens carrier 3. The depth directions of the first and second reflection structures 31 and 33 are arranged to correspond to two mutually perpendicular directions (generally referred to in the art as an X-axis direction and a Y-axis direction) in a plane perpendicular to the optical axis direction of the lens assembly, respectively. The bottom of the first reflecting structure 31 is formed with two first reflecting surfaces 310, the first reflecting surfaces 310 are smooth planes, and the two first reflecting surfaces 310 are perpendicular to each other, and preferably form an included angle of 45 degrees with the X-axis direction. The bottom of the first reflecting structure 33 is formed with two second reflecting surfaces 330, the second reflecting surfaces 330 are smooth planes, and the two second reflecting surfaces 330 are perpendicular to each other, and preferably form an included angle of 45 degrees with the Y-axis direction.

Referring to fig. 7, a third reflecting structure 35 is further formed on the outer surface of the lens carrier 3. In this embodiment, the third reflecting structure 35 is a recess formed at the bottom of the lens carrier 3, and four recesses are formed at the bottom of the lens carrier 3 in the areas adjacent to the four corners. The overall profile of each third reflecting structure 35 is a rectangular groove, two third reflecting surfaces 350 are formed at the bottom, the third reflecting surfaces 350 are smooth planes, and the two third reflecting surfaces 350 are perpendicular to each other, and preferably form an included angle of 45 degrees with the Z-axis direction. In other embodiments, each third reflecting structure 35 may be formed as a concave conical surface, and the conical angle of the conical surface is preferably set to 90 degrees, and the center line is set to be parallel to the Z-axis direction.

The magnets 4 are preferably bar magnets, the number of which is preferably four, and are fixedly mounted on four sides of the lens carrier 3 and are embedded in the magnet accommodating grooves 32, and are preferably also integrally formed with the lens carrier 3 by manufacturing means such as injection molding. The magnet 4 is used to provide the required permanent magnetic field for the AF function and OIS function of the lens driving apparatus.

The shape of the coil carrier 5 may be a substantially cylindrical shape or a hollow prismatic shape, and in this embodiment, a hollow quadrangular prism shape with four corners recessed inward is preferable, and the size thereof is between the housing 1 and the lens carrier 3, so that the coil carrier 5 can be sleeved inside the housing 1, and the lens carrier 3 can be sleeved inside the coil carrier 5.

The focusing coil 6 is preferably a track-shaped coil, the number of the focusing coils is preferably four, the focusing coils are respectively and fixedly arranged on the inner sides of the four side walls of the coil carrier 5, when the focusing coil 6 is electrified, first electromagnetic thrust is received in the magnetic field of the magnet 4, and the reaction force of the first electromagnetic thrust acts on the magnet 4, so that the magnet 4 can be driven to drive the lens carrier 3 and a lens assembly arranged in the lens carrier 3 to move along the optical axis direction of the lens assembly, namely the Z-axis direction, so as to realize an AF function. The focusing coil 4 can be electrically connected with an external power supply through the lens carrier 3 and/or the elastic piece assembly 2 to obtain working voltage. In other embodiments, the focusing coil 6 may be a coil of other shapes such as a loop coil, a rod coil, or the like, the number of which is not limited to four.

The first laser distance measuring device 7 and the second laser distance measuring device 8 may be laser detection plates, both attached to the inner side of the coil carrier 5. The positions of the first laser distance measuring device 7 and the second laser distance measuring device 8 are preferably arranged in two opposite corners inside the coil carrier 5, respectively, such that when the lens carrier 3 is nested inside the coil carrier 5, the position of the first laser distance measuring device 7 may be aligned with the first reflective structure 31 and the position of the second laser distance measuring device 8 may be aligned with the second reflective structure 32. Specifically, the first laser ranging device 7 is provided with a first laser transmitter 71 and a first photoelectric sensor 72, and the first laser transmitter 71 and the first photoelectric sensor 72 are arranged in parallel and can be respectively aligned with the two first reflecting surfaces 310 of the first reflecting structure 31; the second laser ranging device 8 is provided with a second laser transmitter 81 and a second photoelectric sensor 82, and the second laser transmitter 81 and the second photoelectric sensor 82 are arranged in parallel and can be respectively aligned with the two first reflecting surfaces 330 of the second reflecting structure 33.

Referring to fig. 6, 8 and 9, the circuit board 9 is formed in a substantially rectangular flat plate shape with a hollow center, and its outer dimension corresponds to the magnet carrier 5, and can be fitted inside the housing 1. A third laser emitter 91 and a third photoelectric sensor 92 are disposed on a side surface of the circuit board 9, the number of the third laser emitters 91 and the third photoelectric sensors 92 corresponds to the number of the third reflecting structures 35, the third laser emitters 91 and the third photoelectric sensors 92 are disposed in a one-to-one correspondence manner, third laser ranging devices (not numbered in the figure) corresponding to the number of the third reflecting structures 35 are formed on the circuit board 9, and each third laser ranging device comprises one third laser emitter 91 and one third photoelectric sensor 92 disposed in parallel. The positions of the third laser ranging devices are disposed corresponding to the third reflective structures 35 such that the third laser emitters 91 and the third photosensors 92 in each third laser ranging device can be aligned with two third detection surfaces 350 in the corresponding third reflective structure 35, respectively. For example, in this embodiment, the number of the third laser emitters 91 and the third photosensors 92 is four as well as the number of the third reflective structures 35, so as to form four third laser ranging devices, and the third laser emitters 91 and the third photosensors 92 in each third laser ranging device can be aligned with two third detection surfaces 350 in a corresponding one of the third reflective structures 35.

The other side surface of the circuit board 9 is provided with an anti-shake coil 93, and the anti-shake coil 93 may be formed on the side surface of the circuit board 9 by etching so as to reduce the volume and save the space. In the present embodiment, the number of the anti-shake coils 93 is preferably four, and the positions thereof correspond to the four magnets 4, respectively. When the anti-shake coil 93 is energized, the energized anti-shake coil 93 receives a second electromagnetic thrust in the magnetic field of the magnet 4, and the reaction force of the second electromagnetic thrust acts on the magnet 4, so that the magnet 4 can be driven to drive the lens carrier 3 and the lens assembly arranged in the lens carrier 3 to move along the X-axis direction and/or the Y-axis direction, so as to realize the OIS function.

The circuit board 9 may further have a power supply circuit (not shown) for connecting the third laser transmitter 91, the third photosensor 92, and the anti-shake coil 93 to an external power source, and the power supply circuit may be formed inside the circuit board 9 by, for example, burying a wire, a via hole, or the like, or may be formed on the surface of the circuit board 9 by, for example, etching, or the like, so as to save space. The specific structural features and manufacturing method of the power supply circuit can refer to the prior art, and need not be described herein.

The base 10 is formed in a substantially rectangular flat plate shape with a hollow center, and has an outer dimension corresponding to an inner dimension of the housing 1, and is capable of sealing an inner space of the housing 1 from a bottom of the housing 1, so that the base 10 can be mutually matched with the housing 1, and the spring plate assembly 2, the lens carrier 3, the magnet 4, the coil carrier 5, the focusing coil 6, the first laser distance measuring device 7, the second laser distance measuring device 8, and the circuit board 9 are accommodated in a space between the housing 1 and the base 10. The base 10 may also be provided with a plurality of power supply terminals 101 for establishing electrical connection with an external power supply for respective components accommodated in the space between the housing 1 and the base 10.

When the lens driving device is assembled, the magnet 4 may be inserted into the magnet accommodating groove 32 formed on the outside of the lens carrier 3 and fixed, and the focusing coil 6, the first laser distance measuring device 7 and the second laser distance measuring device 8 may be fixed to the inner side of the side wall of the coil carrier 5 in the above arrangement. The lens carrier 3 with the magnet 4 fixed thereto is then nested into the coil carrier 5 with the focusing coil 6 fixed thereto such that the focusing coil 6 is aligned with the magnet 4 with a gap therebetween, the position of the first laser ranging device 7 is aligned with the first reflecting structure 31 on the lens carrier 3, the position of the second laser ranging device 8 is aligned with the second reflecting structure 32 on the lens carrier 3, wherein the first laser transmitter 71 and the first photosensor 72 are aligned with the two first reflecting surfaces 310 of the first reflecting structure 31, respectively, and the second laser transmitter 81 and the second photosensor 82 are aligned with the two first reflecting surfaces 330 of the second reflecting structure 33, respectively.

Connecting two upper spring plates 21 of the spring plate assembly 2 to the top of the lens carrier 3 and enclosing an annular structure surrounding the top surface of the lens carrier 3, and connecting an upper spring plate extension 23 of each upper spring plate 21 to the top of the coil carrier 5; the two lower clips 22 of the clip assembly 2 are connected to the top of the lens carrier 3 and enclose an annular structure around the bottom surface of the lens carrier 3, and the lower clip extension 24 of each lower clip 22 is connected to the bottom of the coil carrier 5. This allows the lens carrier 3 and the coil carrier 5 to be connected together by the spring assembly 2, while the spring assembly 2 can also be used to provide an electrical connection between the lens carrier 3 and the coil carrier 5. Due to the elasticity of the spring assembly 2, the lens carrier 3 and the magnet 4 fixed thereon can perform a recoverable motion relative to the coil carrier 5 under the action of external force.

The circuit board 10 is fixedly mounted to the base 10 with the side surface of the circuit board 9 provided with the anti-shake coil 93 facing the base 10. Then, the spring plate assembly 2, the lens carrier 3, the magnet 4, the coil carrier 5 and the coil 6 assembled together in the foregoing manner are placed on the surface of one side of the circuit board 9 where the third laser emitter 91 and the third photoelectric sensor 92 are provided, so that each third laser ranging device on the circuit board 9, which is composed of the third laser emitter 91 and the third photoelectric sensor 92 that are arranged in parallel, is aligned with a corresponding one of the third detection structures 35 on the lens carrier 3, where the third laser emitter 91 and the third photoelectric sensor 92 are aligned with two third detection surfaces 350 in the corresponding third detection structure 35, respectively. After alignment, the coil carrier 5 and the circuit board 9 and the base 10 are fixed to each other. Finally, the shell 1 is covered on the base 10, and the shell fragment assembly 2, the lens carrier 3, the magnet 4, the coil carrier 5, the focusing coil 6, the first laser ranging device 7, the second laser ranging device 8 and the circuit board 9 are packaged between the shell 1 and the base 10, so that the lens driving device is assembled. The specific technical means for establishing electrical connection between each component and the outside may refer to the prior art, and will not be described herein.

In use of the lens driving device, for example, an existing lens assembly can be fixed in the mounting hole 30 of the lens carrier 3 in a conventional assembly mode, the front end of the lens assembly extends out of the housing 1 through the lens hole 1c to shoot images, the rear end of the lens assembly is exposed through the lower spring plate 7, the circuit board 9 and the hollowed-out middle area of the base 10, thus, for example, an existing image sensor assembly can be arranged outside the base 10, the image sensor assembly is aligned with the rear end of the lens assembly, and the optical signals shot by the lens assembly can be acquired by using the image sensor assembly for imaging. The structural features and working principles of the lens assembly and the image sensor assembly can be fully referred to the prior art, and those skilled in the art will readily understand the same, so that no detailed description is required herein, and no drawing is necessary.

In use, the lens driving apparatus may be used to provide an AF function and OIS function for a lens assembly mounted therein. The specific working principle is described in detail below.

According to the above-described assembly method, the housing 1, the coil carrier 5, the focusing coil 6, the first laser distance measuring device 7, the second laser distance measuring device 8, the circuit board 9 and the base 10 in the lens driving device together form a stator assembly of the lens driving device, while the lens carrier 3 and the magnet 4 fixed thereon are connected with the stator assembly through the spring plate assembly 2, and a recoverable motion can be generated with respect to the stator assembly based on the elasticity of the spring plate assembly 2, so that the lens carrier 3 and the magnet 4 together form a sub-assembly of the lens driving device, and the lens assembly is mounted in the sub-assembly.

Based on the structural arrangement of the stator assembly and the rotor assembly, when the lens assembly needs to perform AF operation, the focusing coil 6 can be powered by the existing technical means, for example, and the focusing coil 6 receives first electromagnetic thrust in the magnetic field of the magnet 4 after being powered; since the focusing coil 4 is fixed, the reaction force of the first electromagnetic thrust acts on the magnet 4 at this time, and the driving sub-assembly and the lens assembly mounted therein move along the optical axis direction of the lens assembly, i.e., the above-mentioned Z-axis direction, thereby adjusting the distance between the lens assembly and the image sensor assembly disposed outside the base 10, and thus the AF function is realized. The direction and the magnitude of the current passing through the focusing coil 6 can be adjusted by adjusting the direction and the magnitude of the voltage applied to the focusing coil 6, so that the first electromagnetic thrust acted by the focusing coil 6 and the direction and the magnitude of the corresponding reaction force applied to the magnet 4 are adjusted, and the purpose of accurate focusing is achieved; the specific regulation methods of the relevant voltages and currents can be fully referred to the prior art, and need not be described here in detail. During the AF operation, the upper and lower elastic pieces 21 and 22 are elastically deformable based on their own elasticity, allowing the lens carrier 3 to move relative to the coil carrier 5; when the operation is finished, the upper spring piece 21 and the lower spring piece 22 recover from the elastic deformation state, and the lens carrier 3 is driven to reset.

When OIS operation is required, the circuit board 9 may be powered by, for example, existing technical means, and the anti-shake coil 93 on the anti-shake circuit board 9 receives a second electromagnetic thrust in the magnetic field of the magnet 4 after being electrified; since the circuit board 9 is fixed, the reaction force of the second electromagnetic thrust acts on the magnet 4, and the driving sub-assembly and the lens assembly mounted therein move in directions perpendicular to the optical axis direction of the lens assembly, i.e., the X-axis direction and the Y-axis direction, to compensate for the offset of the lens assembly relative to the image sensor assembly due to the shake in the X-axis direction and/or the Y-axis direction, so that the lens assembly and the image sensor assembly are kept aligned. By adjusting the direction and magnitude of the voltage applied to the anti-shake coil 93, the direction and magnitude of the current passing through the anti-shake coil 93 can be adjusted, and the second electromagnetic thrust applied to the anti-shake coil 93 and the direction and magnitude applied to the magnet 4 correspondingly can be adjusted, so that the purpose of accurately performing OIS can be achieved; the specific regulation methods of the relevant voltages and currents can be fully referred to the prior art, and need not be described here in detail. During OIS operation, the upper and lower spring plates 21, 22 are capable of undergoing elastic deformation based on their own elasticity, allowing the lens carrier 3 to move relative to the coil carrier 5; when the operation is finished, the upper spring piece 21 and the lower spring piece 22 recover from the elastic deformation state, and the lens carrier 3 is driven to reset.

In particular, in the use process of the lens driving device provided in the present embodiment, the hall element is not used to detect the real-time position of the lens assembly relative to the stator assembly, but the real-time position of the sub-assembly and the lens assembly mounted therein relative to the stator assembly is detected by the technical means of laser ranging, so as to be used as a reference for controlling the sub-assembly to perform position compensation during AF operation and OIS operation.

Referring to fig. 10, the basic principle of the laser ranging method adopted in the present embodiment is to indirectly measure the laser flight time by measuring the phase offset between the transmitted laser signal and the received laser signal, that is, measuring the phase difference between the transmitted sine wave or square wave laser signal and the received sine wave or square wave laser signal, so as to calculate the distance according to the laser flight time. As shown in fig. 10, for example, the distances can be calculated using the transmission/reception phase differences generated by the laser signals with four phase delays of 0 °, 90 °, 180 °, 270 °, respectively; wherein the phase difference is shown in the figureThe calculation formula of (2) is as follows:

calculating the phase differenceThereafter, the laser signal can be further processed according to the sine wave or square wave frequency f (number of parameters The value is a preset constant) and the speed of light c (the value of the parameter is common knowledge) calculate the optical path S that the laser signal travels from transmitting to being received:

referring to fig. 11, a schematic diagram of a laser path when determining a position of a sub-assembly by using a laser ranging method based on the laser ranging principle shown in fig. 10 is shown in this embodiment. Specifically, fig. 11 is a schematic view of the laser light path when the first laser distance measuring device 7 and the first reflecting structure 31 of the lens carrier 3 are used to perform laser distance measurement. As shown in the figure, in use, the first laser transmitter 71 and the first photosensor 72 of the first laser ranging device 7 are aligned with the two first reflecting surfaces 310 of the first reflecting structure 31, respectively, and the first laser transmitter 71 emits a sinusoidal wave or square wave laser signal with a transmission direction parallel to the X-axis. Since the two first reflecting surfaces 310 are both 45 degrees with respect to the X-axis and the two first reflecting surfaces 310 are perpendicular to each other, the transmission direction of the laser signal is turned 90 degrees when the laser signal is transmitted to the first reflecting surface 310 aligned with the first laser transmitter 71, is transmitted to the other first reflecting surface 310 aligned with the first photosensor 72, is turned 90 degrees again when the laser signal is reflected, and is transmitted to the first photosensor 72. After receiving the returned laser signal by the first photosensor 72, the phase difference between the laser signal emitted from the first laser emitter 71 and the laser signal received by the first photosensor 72 can be determined by an existing signal processing device, such as a main control unit (not shown) in an existing image pickup apparatus The optical path S through which the laser signal is transmitted from the first laser transmitter 71 to the first photosensor 72 is then calculated according to the foregoing formula. Finally, according to the sine wave or square wave frequency f of the laser signal (the value of the parameter is a preset constant), the laserThe distance b between the reflection points of the signals on the two first reflection surfaces 310 (the value of the parameter is a preset constant) and the speed of light c (the value of the parameter is common knowledge), namely, the distance d between the first laser transmitter 71 or the first photosensor 72 and the corresponding first reflection surface 310 can be calculated by the following formula:

said distance d can be used as a real-time reference distance between the first laser distance measuring device 7 and the lens carrier 3. Obviously, as long as the above-mentioned laser ranging operation is continuously performed at a preset detection frequency, the distance between the first laser ranging device 7 and the lens carrier 3 can be determined in real time, the displacement of the sub-assembly and the lens assembly mounted therein relative to the stator assembly in the X-axis direction can be determined in real time according to the change of the distance, and the sub-assembly can be controlled to move in the X-axis direction to perform corresponding position compensation according to the displacement when the OIS operation is performed.

It can be understood that, by using similar laser ranging operation means, the distance between the second laser ranging device 7 and the lens carrier 3 can be determined in real time, and the displacement of the sub-assembly and the lens assembly installed therein relative to the stator assembly in the Y-axis direction can be determined in real time according to the change condition of the distance, and the sub-assembly can be controlled to move in the Y-axis direction according to the displacement condition to perform corresponding position compensation when the OIS operation is performed; the distance between the third laser distance measuring device and the lens carrier 3 can be determined in real time, the displacement of the sub-assembly and the lens assembly arranged in the sub-assembly relative to the stator assembly in the Z-axis direction can be determined in real time according to the change condition of the distance, and the sub-assembly can be controlled to move in the Z-axis direction according to the deviation condition to perform corresponding position compensation when the AF operation is performed. It can be seen that the lens driving device provided in this embodiment can implement the detection of the real-time position of the sub-assembly and the lens assembly mounted therein relative to the stator assembly by using the laser ranging technique instead of the hall element in all three directions (for example, the aforementioned X-axis direction, Y-axis direction and Z-axis direction) perpendicular to each other in the three-dimensional space, so as to be used as a reference basis for controlling the sub-assembly to perform the position compensation in the AF operation and the OIS operation.

Compared with the prior art, the lens driving device provided by the preferred embodiment of the application replaces the hall element by the technical means of laser ranging to detect the real-time position of the sub-assembly of the lens driving device and the lens assembly arranged in the sub-assembly relative to the stator assembly, so as to be used as a reference basis for controlling the sub-assembly to perform position compensation in the AF operation and the OIS operation. Because the Hall element is not used in the technical scheme, the rotor component and the lens component are not subjected to external electromagnetic interference when being subjected to position detection, and electromagnetic interference is not generated at the same time; and the laser ranging technical means that this application's technical scheme used compares with hall element, and response that distance detected is faster, the precision is higher, and manufacturing cost is lower, also saves assembly space more.

In other embodiments, at least one of the first, second and third laser distance measuring devices 7, 8 may also be provided on the sub-assembly, e.g. mounted on the lens carrier 3; accordingly, at least one of the first, second and third reflective structures 31, 33 and 35 may also be provided on the stator assembly, for example, the first and second reflective structures 31, 33 may be formed on an inner surface of the coil carrier 5, and the third reflective structure 35 may be formed on a surface of the circuit board 9 facing the lens carrier 3.

In other embodiments, the number and positions of the first laser ranging device 7, the second laser ranging device 8, and the third laser ranging device may be changed as long as the above-described position detection function for the sub-assembly and the lens assembly can be achieved. It should be noted that the number of third laser ranging devices and the number of corresponding third reflecting structures 35 are preferably plural, because according to the above detection means, the displacements of the plurality of positions of the sub-assembly in the Z-axis direction relative to the stator assembly can be detected simultaneously by the plurality of third laser ranging devices and the corresponding third reflecting structures 35, and whether the sub-assembly and the lens assembly are angularly deflected in the Z-axis direction relative to the stator assembly can be determined by comparing the displacements of the plurality of positions of the sub-assembly in the Z-axis direction relative to the stator assembly with each other (for example, when the displacements of the two positions of the sub-assembly in the Z-axis direction relative to the stator assembly are different, the angular deflection of the sub-assembly and the lens assembly in the Z-axis direction relative to the stator assembly can be determined); further, a specific angle of deflection can be calculated according to specific displacement amounts of a plurality of positions of the sub-assembly relative to the stator assembly in the Z-axis direction, and the specific angle is used as a reference basis for angle compensation of the lens assembly.

In other embodiments, the lens driving device may also include only one or two of the first, second and third laser ranging devices 7, 8 and 35, and one or two of the first, second and third reflective structures 31, 33 and 35, respectively. When in use, the position detection of the sub-assembly and the lens assembly mounted therein is performed by using the laser ranging device and the corresponding reflecting structure thereof in one or two directions of the X-axis direction, the Y-axis direction and the Z-axis direction according to the method, while the position detection of the sub-assembly and the lens assembly mounted therein can be performed by using the prior art means in other directions.

In other embodiments, the specific shapes of the first, second and third laser ranging devices and the corresponding first, second and third reflecting structures are not limited to the above shapes, as long as the corresponding laser reflecting functions can be realized for ranging. For example, the self-extending direction or diagonal direction of the two reflecting surfaces in each reflecting structure may also be arranged to form an acute angle, preferably an acute angle smaller than 45 degrees, with the transmission direction of the laser signal generated by the corresponding laser ranging device; each reflecting structure may also comprise only one reflecting surface, which is smooth and whose normal direction is arranged at a small acute angle to the direction of transmission of the laser signal generated by the respective laser distance measuring device.

An embodiment of another aspect of the present application provides an image pickup apparatus including the lens driving device, and the lens assembly and the image sensor assembly described in the foregoing embodiments. The lens component is fixed in the mounting hole 30 of the lens carrier 3, the front end of the lens component extends out of the shell 1 through the lens hole 1c to shoot images, and the rear end of the lens component is exposed through the lower spring plate 7, the anti-shake circuit board 9 and the hollowed-out middle area of the base 10; the image sensor assembly is disposed outside the base 10 and aligned with the rear end of the lens assembly such that the image sensor assembly can capture the optical signals taken by the lens assembly for imaging. The structural features and working principles of the lens assembly and the image sensor assembly can be fully referred to the prior art, and those skilled in the art will readily understand the same, so that no detailed description is required herein, and no drawing is necessary. Obviously, the image pickup apparatus can perform work with reference to the operation principle of the lens driving device described in the foregoing embodiment, and the above advantageous technical effects of the lens driving device can also be obtained.

Embodiments of another aspect of the present application also provide a smart terminal, which may be, for example, a smart phone, a tablet computer, a personal computer, a wearable device, etc., and which includes the image capturing device as described in the foregoing embodiments.

The foregoing is merely specific embodiments of the present application, but the scope of the present application is not limited thereto, and any changes or substitutions easily conceivable by those skilled in the art within the technical scope of the present application should be covered in the scope of the present application. Accordingly, the scope of protection of the present application shall be subject to the appended claims.

Claims (10)

1. The lens driving device is characterized by comprising a stator assembly and a rotor assembly, wherein the stator assembly and the rotor assembly are connected in a relatively movable manner; one of the stator assembly and the sub-assembly comprises a laser ranging device, the other one comprises a reflecting structure corresponding to the laser ranging device, the laser ranging device is used for sending laser signals to the reflecting structure, the reflecting structure is used for reflecting the laser signals back to the laser ranging device, so that the distance between the stator assembly and the sub-assembly is detected in a laser ranging mode, and the displacement of the sub-assembly relative to the stator assembly is determined according to the distance.

2. The lens driving apparatus of claim 1, wherein the laser ranging apparatus comprises a first laser ranging apparatus, a second laser ranging apparatus, and a third laser ranging apparatus, and the reflecting structure comprises a first reflecting structure, a second reflecting structure, and a third reflecting structure; the first laser ranging device and the first reflecting structure are used for detecting displacement of the sub-assembly relative to the stator assembly in a first direction, the second laser ranging device and the second reflecting structure are used for detecting displacement of the sub-assembly relative to the stator assembly in a second direction, the third laser ranging device and the third reflecting structure are used for detecting displacement of the sub-assembly relative to the stator assembly in a third direction, and the first direction, the second direction and the third direction are mutually perpendicular.

3. The lens driving apparatus of claim 2, wherein the number of the third laser ranging devices and the third reflecting structures is plural, and the plurality of third laser ranging devices and the plurality of third reflecting structures are used to simultaneously detect displacements of the plurality of positions of the sub-assembly with respect to the stator assembly in the third direction to detect angular deflection of the sub-assembly with respect to the stator assembly in the third direction.

4. The lens driving apparatus of claim 2, wherein the stator assembly further comprises a coil carrier and a focusing coil, the first laser ranging apparatus, the second laser ranging apparatus, and the focusing coil being mounted on the coil carrier; the sub-assembly further comprises a lens carrier and a magnet arranged on the lens carrier, and the first reflecting structure and the second reflecting structure are formed on the lens carrier; the focusing coil and the magnet are used for generating first electromagnetic thrust to drive the sub-assembly to focus.

5. The lens driving apparatus of claim 4, wherein the lens carrier is sleeved inside the coil carrier, the first laser ranging device, the second laser ranging device and the focusing coil are all mounted on an inner surface of the coil carrier, and the first reflecting structure and the second reflecting structure are both formed on an outer surface of the lens carrier and aligned with the first laser ranging device and the second laser ranging device, respectively.

6. The lens driving apparatus of claim 4, further comprising a spring assembly having elasticity and connecting the lens carrier and the coil carrier to be movable relatively.

7. The lens driving apparatus of claim 4, wherein the stator assembly further comprises a circuit board, the third laser ranging device being disposed on the circuit board, the third reflective structure being formed on the lens carrier and aligned with the third laser ranging device; the circuit board comprises an anti-shake coil, and the anti-shake coil and the magnet are used for generating second electromagnetic thrust to drive the rotor assembly to perform optical anti-shake.

8. The lens driving apparatus of claim 7, wherein the third laser ranging device and the anti-shake coil are disposed on two opposite surfaces of the circuit board, respectively.

9. An image pickup apparatus comprising a lens assembly, an image sensor assembly, and the lens driving device according to any one of claims 1 to 8, the lens assembly being mounted in the sub-assembly of the lens driving device, the image sensor assembly being configured to acquire an optical signal taken by the lens assembly for imaging.

10. An intelligent terminal comprising the image pickup apparatus according to claim 9.