CN115550630A

CN115550630A - Lens position detection system, lens position detection method, voice coil motor and voice coil motor equipment

Info

Publication number: CN115550630A
Application number: CN202210074232.6A
Authority: CN
Inventors: 原帅; 吴鹏
Original assignee: Honor Device Co Ltd
Current assignee: Honor Device Co Ltd
Priority date: 2022-01-21
Filing date: 2022-01-21
Publication date: 2022-12-30
Anticipated expiration: 2042-01-21
Also published as: CN115550630B

Abstract

The application provides a lens position detection system, a lens position detection method, a voice coil motor and electronic equipment, and relates to the technical field of terminals. The detection system comprises: detection module and controller. The detection module comprises a first magnet, a second magnet, a coil and a magnetic core. The coil is arranged in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and the lens is fixed, the coil surrounds the outer part of the magnetic core, and the position of the magnetic core is fixed. The controller controls the driving voltage of the coil to be a first voltage so as to enable the coil and the magnetic core to move relatively, when the coil is determined to reach the first position, the driving voltage of the coil is controlled to be a second voltage, the position of the lens is determined by utilizing the current of the output end of the coil, the first voltage is direct current voltage, the second voltage is alternating current voltage, and effective values of the first voltage and the second voltage are the same. The scheme can reduce hardware cost, does not increase the size of the device in the direction of the optical axis and the direction vertical to the optical axis too much, and reduces occupied space.

Description

Lens position detection system, lens position detection method, voice coil motor and voice coil motor equipment

Technical Field

The present application relates to the field of terminal technologies, and in particular, to a system and a method for detecting a lens position, a voice coil motor, and an electronic device.

Background

The present electronic device generally has a shooting function, and during the shooting process of the electronic device, a Voice Coil Motor (VCM) is usually used to adjust a position of a lens of a camera module, so as to implement functions such as auto focus. The operating principle of VCM is as follows: the electrified coil is stressed to move in a magnetic field to drive the lens to move. Wherein, the relative position of coil and camera lens is fixed.

Because of the influence of the environment where the lens is located when the lens is actually shot, the coil drives the lens to move the displacement actually generated, which may be different from the preset displacement, so that the actual position of the lens needs to be detected.

At present, a Hall sensor (Hall sensor) is generally used to determine an actual position of a lens, specifically, a Hall element of the Hall sensor is placed in a magnetic field of a VCM, a current orthogonal to a direction of the magnetic field is applied to the Hall element, a displacement of a coil is determined according to a magnitude of a potential difference between two ends of the Hall element, and then a relative position of the coil and the lens is fixed to obtain a position of the lens. However, the cost of the hall sensor is high, so that the hardware cost is increased, and the camera module is required to be increased in size in order to avoid the position of the hall sensor.

Therefore, the current method of acquiring the lens position significantly increases the hardware cost and the occupied space.

Disclosure of Invention

In order to solve the above problems, the present application provides a lens position detection system, a lens position detection method, a voice coil motor, and an electronic device, which reduce hardware cost and occupied space.

In a first aspect, the present application provides a system for detecting a position of a lens, which is applied to determine a position of a lens in a camera module. The detection device includes: detection module and controller. The detection module comprises a first magnet, a second magnet, a coil and a magnetic core. The detection module is also the VCM, the relative position of the coil and the lens is fixed, and the coil is positioned in a magnetic field formed by the first magnet and the second magnet, so that the coil can generate displacement in the magnetic field after being electrified, and the lens is driven to move. The coil is wound outside the magnetic core, and the position of the magnetic core is fixed, namely the coil and the magnetic core move relatively after being electrified. The controller controls the driving voltage of the coil to be a first voltage, and the first voltage is direct current voltage. When the two ends of the coil are connected with a first voltage, the coil and the magnetic core move relatively, the inductance of the coil changes, when the controller determines that the coil reaches a first position, the driving voltage of the coil is controlled to be a second voltage, the second voltage is an alternating voltage, and the effective values of the first voltage and the second voltage are the same. The controller now determines the position of the lens using the current at the output of the coil.

The first position represents that the coil stops moving at the moment, the effective value of the second voltage is the same as that of the first voltage, namely when the driving voltage of the control coil is the second voltage, the coil does not continue to move.

Utilize the scheme that this application provided, a magnetic core is nested in VCM's in electronic equipment's coil, realize to the detection of camera lens position, it is less to set up the influence of magnetic core to VCM's size, and in some embodiments, VCM's size can remain unchanged, has still avoided adopting hall sensor, can reduce hardware cost to do not have too much increase device size in optical axis direction and the direction of perpendicular to optical axis, reduce the space that occupies.

In one possible implementation, the controller is specifically configured to superimpose the first voltage with a preset alternating voltage to obtain the second voltage.

The first voltage is direct current voltage, and the second voltage is alternating voltage, and the superposition of first voltage and preset alternating voltage can realize that the effective values of first voltage and second voltage are the same to make the coil can not continue to take place to remove after reaching first position.

In one possible implementation, the controller is specifically configured to determine the displacement of the coil using the current at the output of the coil, and to determine the position of the lens based on the relative positions of the coil and the lens.

Since the relative positions of the coil and the lens are not changed, the coil drives the lens to move when moving. Thus, by determining the actual displacement of the coil, and from the relative positions of the coil and the lens, the position of the lens can be determined.

In a possible implementation manner, the controller is specifically configured to determine the inductance of the coil according to the current at the output end of the coil and a preset alternating voltage, and determine the displacement of the coil according to a pre-calibrated correspondence between the inductance and the displacement of the coil.

Because relative motion exists between the magnetic core and the coil, the inductance of the coil can be changed, and therefore the displacement of the coil, namely the displacement of the relative motion between the magnetic core and the coil, can be determined through the inductance of the coil.

In a possible implementation manner, the controller is specifically configured to determine the displacement of the coil according to a pre-calibrated correspondence between the current and the displacement of the coil and the current at the output end of the coil.

The above method directly utilizes the current at the output end of the coil, and can simplify the processing process.

In a possible implementation manner, the controller is specifically configured to determine the inductance of the coil by using the current at the output end of the coil and a preset alternating voltage, and determine the position of the lens according to a pre-calibrated correspondence between the inductance and the position of the lens.

According to the corresponding relation between the inductor and the lens position calibrated in advance, the lens position can be directly obtained according to the inductor, and the processing process can be simplified.

In a possible implementation manner, the controller is specifically configured to determine the position of the lens by using a pre-calibrated correspondence between the current and the lens position and the current at the output end of the coil.

The current of the coil output end is directly utilized in the mode, the position of the lens can be directly obtained according to the current, and the processing process can be simplified.

In one possible implementation, the controller is specifically configured to determine that the coil reaches the first position after controlling the driving voltage of the coil to be the first voltage for a preset time period.

The coil is determined to reach the first position according to the preset time period, the determination process is simple, and the coil can be determined to reach the first position simply, conveniently and efficiently.

In one possible implementation, the controller is specifically configured to determine that the coil reaches the first position when the current at the output of the coil is constant.

When the voltage across the coil is a constant dc voltage, the current of the coil is generally constant; cutting the magnetically sensitive wire when the energized coil moves in the magnetic field produces an electromotive force in a direction opposite to the voltage across the coil, and therefore the current in the coil is not constant during the movement of the coil.

When the coil stops moving, the electromotive force generated by the coil cutting the magnetic induction wire disappears, so that the current of the coil is kept unchanged. Therefore, when the current at the output end of the coil is constant, it can be determined that the coil stops moving, that is, that the coil reaches the first position.

Due to the fact that unexpected movement can be generated due to the fact that the coil is influenced by other factors in the moving process, the mode that the coil is determined to stop moving can be used for reducing the occurrence of error results caused by accidental situations, and therefore the accuracy of lens position detection is improved.

In a possible implementation manner, the magnetic core in the lens position detection system has a hollow structure, so that the lens can be nested in the hollow structure of the magnetic core, and the size of the whole camera module is reduced.

In a second aspect, the present application provides a system for detecting a position of a lens, which includes a detection module and a controller.

The detection module comprises a magnetic component, a coil and a magnetic core. The detection module is also called VCM, the coil surrounds the magnetic core, the position of the coil is fixed, and the relative position of the magnetic component and the magnetic core is fixed, so that after the coil is electrified, the magnetic component and the coil move relatively, and then the magnetic component drives the lens to move.

The controller is used for controlling the driving voltage of the control coil to be a first voltage so as to enable the magnetic component and the coil to move relatively, when the magnetic component is determined to reach the first position, the driving voltage of the control coil is a second voltage, the position of the lens is determined by utilizing the current of the output end of the coil, the first voltage is a direct current voltage, the second voltage is an alternating current voltage, and the effective values of the first voltage and the second voltage are the same. The controller now determines the position of the lens using the current at the output of the coil.

The first position representation indicates that the magnetic component stops moving at the moment, the effective value of the second voltage is the same as that of the first voltage, namely when the driving voltage of the control coil is the second voltage, the magnetic component does not continue to move.

Utilize the scheme that this application provided, a magnetic core is nested in VCM's in electronic equipment's coil, realize the detection to the camera lens position, it is less to the influence of VCM's size to set up the magnetic core, and in some embodiments, VCM's size can remain unchanged, has still avoided adopting hall sensor, can reduce hardware cost to do not have too much increase device size in optical axis direction and the direction of perpendicular to optical axis, reduce the space that occupies.

In one possible implementation, the controller is specifically configured to determine the displacement of the magnetic component using the current at the output of the coil, and to determine the position of the lens based on the relative positions of the magnetic component and the lens.

Because the relative position of the magnetic part and the lens is not changed, the magnetic part can drive the lens to move when moving. Therefore, by determining the actual displacement of the magnetic member and from the relative positions of the magnetic member and the lens, the position of the lens can be determined.

In a possible implementation manner, the controller is specifically configured to determine the inductance of the coil according to the current at the output end of the coil and a preset alternating voltage, and determine the displacement of the magnetic component according to a pre-calibrated correspondence between the inductance and the displacement of the magnetic component.

Because the coil is fixed, the relative position of the magnetic part and the magnetic core is fixed, after the coil is electrified, the magnetic part and the coil move relatively, and then the magnetic part drives the lens to move. The inductance of the coil changes due to the relative motion between the core and the coil, so that the displacement of the magnetic component can be determined by the inductance of the coil.

In a possible implementation manner, the controller is specifically configured to determine the displacement of the magnetic component according to a pre-calibrated correspondence between the current and the displacement of the magnetic component and the current at the output end of the coil.

In a possible implementation manner, the controller is specifically configured to determine the inductance of the coil by using the current at the output end of the coil and a preset alternating voltage, and determine the position of the lens according to a correspondence between the inductance and the lens position that are calibrated in advance.

In one possible implementation, the controller is specifically configured to determine that the magnetic member reaches the first position after controlling the driving voltage of the coil to be the first voltage for a preset time period.

The coil arrival first position is determined according to the preset time period, the determination process is simple, and the coil arrival first position can be determined simply, conveniently and efficiently.

In a possible implementation, the controller is specifically configured to determine that the magnetic component reaches the first position when the current at the output of the coil is constant.

When the voltage across the coil is a constant dc voltage, the current of the coil is generally a constant current; when a magnetic field is generated around the energized coil, the magnetic member moves in the magnetic field. Because the position of the coil is fixed, relative motion is generated between the coil and the magnetic component, so that the energized coil cuts the magnetic induction lines in the magnetic field generated by the magnetic member, and the coil cuts the magnetic induction lines to generate electromotive force. Therefore, during the movement of the magnetic member, the coil cuts the electromotive force generated by the magnetic induction wire, so that the current passing through the coil is varied.

When the magnetic component stops moving, the electromotive force generated by the coil cutting the magnetic induction line disappears, so that the current of the coil does not change. Therefore, when the current at the output end of the coil is constant, it can be determined that the magnetic member stops moving, that is, that the magnetic member reaches the first position.

Since the magnetic component may be influenced by other factors to generate unexpected movement during the movement, the manner of determining the stop of the movement of the magnetic component can reduce the occurrence of error results caused by accidental situations.

In one possible implementation, the coil in the lens position detection system surrounds the outside of the magnetic component to reduce the size of the detection module, i.e., the VCM.

In a third aspect, the present application provides a voice coil motor.

The voice coil motor includes a first magnet, a second magnet, a coil, and a magnetic core. The coil is located in a magnetic field formed by the first magnet and the second magnet, the coil surrounds the magnetic core, and the position of the magnetic core is fixed. The coil is used for generating displacement corresponding to the external driving voltage when the external driving voltage is applied.

By adopting the voice coil motor provided by the application, the lens can be driven to move by the movement of the electrified coil in the magnetic field formed by the first magnet and the second magnet, so that the position of the lens can be adjusted and determined; in addition, a Hall sensor is not utilized when the position of the lens is determined, so that the hardware cost can be reduced, and the occupied space can be reduced.

In a fourth aspect, the present application provides a voice coil motor.

The voice coil motor includes a magnetic member, a coil, and a magnetic core. The coil is wound outside the magnetic core, and the position of the coil is fixed; the relative positions of the magnetic component and the magnetic core are fixed; the magnetic component is used for generating movement corresponding to the external driving voltage when the coil is externally connected with the driving voltage.

By adopting the voice coil motor provided by the application, the magnetic part generates movement corresponding to the external driving voltage when the coil is externally connected with the driving voltage, so that the magnetic part can drive the lens to move, and the adjustment and determination of the position of the lens are realized; in addition, a Hall sensor is not utilized when the position of the lens is determined, so that the hardware cost can be reduced, and the occupied space can be reduced.

In a fifth aspect, the present application provides a method for detecting a lens position, where the method is applied to a side detection module. The detection module comprises a first magnet, a second magnet, a coil and a magnetic core. The detection module is also the VCM.

The coil is positioned in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and the lens is fixed, the coil surrounds the outer part of the magnetic core, and the position of the magnetic core is fixed. The method comprises the following steps: controlling the driving voltage of the coil to be a first voltage so as to enable the coil and the magnetic core to move relatively, wherein the first voltage is a direct-current voltage; when the coil reaches the first position, controlling the driving voltage of the coil to be a second voltage, wherein the second voltage is an alternating voltage, and the effective values of the first voltage and the second voltage are the same; the position of the lens is determined by the current at the output of the coil.

In a possible implementation manner, controlling the driving voltage of the coil to be the second voltage specifically includes:

and superposing the first voltage and a preset alternating voltage to obtain a second voltage.

In a possible implementation manner, the determining the position of the lens by using the current at the output end of the coil specifically includes:

determining the displacement of the coil by using the current at the output end of the coil; and determining the position of the lens according to the relative positions of the coil and the lens.

Because the relative position of the coil and the lens is not changed, the coil can drive the lens to move when moving. Thus, by determining the actual displacement of the coil, and from the relative positions of the coil and the lens, the position of the lens can be determined.

In a possible implementation manner, determining the displacement of the coil by using the current at the output end of the coil specifically includes:

determining the inductance of the coil according to the current of the output end of the coil and the preset alternating voltage; and determining the displacement of the coil according to the corresponding relation between the inductance and the coil displacement which are calibrated in advance.

and determining the displacement of the coil according to the corresponding relation between the pre-calibrated current and the coil displacement and the current of the output end of the coil.

determining the inductance of the coil by using the current at the output end of the coil and the preset alternating voltage; and determining the position of the lens according to the corresponding relation between the pre-calibrated inductance and the position of the lens.

and determining the position of the lens by using the corresponding relation between the pre-calibrated current and the position of the lens and the current of the output end of the coil.

In a sixth aspect, the present application provides a method for detecting a lens position, which is applied to a side detection module, where the side detection module includes a magnetic component, a coil, and a magnetic core; the coil is wound outside the magnetic core, and the position of the coil is fixed; the relative position of the magnetic component and the magnetic core is fixed, and the method comprises the following steps:

controlling the driving voltage of the control coil to be a first voltage so as to enable the magnetic component and the coil to move relatively, wherein the first voltage is a direct-current voltage; when the magnetic component is determined to reach the first position, the driving voltage of the control coil is a second voltage, the second voltage is an alternating current voltage, and the effective values of the first voltage and the second voltage are the same; the position of the lens is determined by the current at the output of the coil.

and superposing the first voltage and a preset alternating current voltage to obtain a second voltage.

determining the displacement of the magnetic component by using the current of the output end of the coil; and determining the position of the lens according to the relative positions of the magnetic component and the lens.

Because the relative position of the magnetic part and the lens is unchanged, the magnetic part drives the lens to move when moving. Therefore, by determining the actual displacement of the magnetic member, and from the relative positions of the magnetic member and the lens, the position of the lens can be determined.

In a possible implementation, the determining the displacement of the magnetic component by using the current at the output of the coil specifically comprises:

determining the inductance of the coil according to the current of the output end of the coil and the preset alternating voltage; and determining the displacement of the magnetic component according to the corresponding relation between the pre-calibrated inductance and the displacement of the magnetic component.

Because the coil is fixed, the relative position of the magnetic part and the magnetic core is fixed, after the coil is electrified, the magnetic part and the coil move relatively, and then the magnetic part drives the lens to move. The inductance of the coil changes due to the relative motion between the core and the coil, so that the magnetic component displacement can be determined by the inductance of the coil.

and determining the displacement of the magnetic component according to the corresponding relation between the pre-calibrated current and the displacement of the magnetic component and the current of the output end of the coil.

determining the inductance of the coil by using the current of the output end of the coil and the preset alternating voltage; and determining the position of the lens according to the corresponding relation between the pre-calibrated inductance and the position of the lens.

In a seventh aspect, the present application provides an electronic device. The electronic device comprises a lens position detection system as described in any of the above. The electronic device also includes a lens. The system for detecting the position of the lens is applied to determining the position of the lens module in the electronic equipment.

Utilize the scheme that this application provided, a magnetic core is nested in VCM's in electronic equipment's coil, realize the detection to the camera lens position, it is less to the influence of VCM's size to set up the magnetic core, in some embodiments, VCM's size can remain unchanged, still avoided adopting hall sensor, can reduce hardware cost, and do not have too much increase device size in optical axis direction and the direction of perpendicular to optical axis, reduce the space that occupies, thereby make the space of the camera lens module in electronic equipment occupy.

Drawings

Fig. 1A is a schematic structural diagram of an electronic device according to an embodiment of the present application;

FIG. 1B is an exploded view of FIG. 1A;

fig. 1C is a schematic structural diagram of a camera module provided in the embodiment of the present application;

FIG. 1D is an exploded view of FIG. 1C;

FIG. 1E is a schematic diagram illustrating the operation of a voice coil motor;

fig. 1F is a schematic structural diagram of an assembly of a voice coil motor and a lens provided in the present application;

fig. 2A is a schematic structural diagram of a lens position detection system according to an embodiment of the present disclosure;

fig. 2B is a schematic structural diagram of another lens position detection system according to an embodiment of the present disclosure;

fig. 2C is a schematic diagram of a driving voltage of a coil and a current at an output end of the coil according to an embodiment of the present application;

fig. 3A is a schematic structural diagram of a lens position detection system according to another embodiment of the present disclosure;

fig. 3B is a schematic cross-sectional view illustrating an assembly of a voice coil motor according to an embodiment of the present application;

FIG. 3C is an exploded view of FIG. 3B;

fig. 3D is a diagram of a corresponding relationship between an inductance and an actual displacement of a coil provided in the embodiment of the present application;

fig. 4 is a schematic structural diagram of a lens position detection system according to another embodiment of the present application;

fig. 5 is a schematic structural diagram of a voice coil motor according to an embodiment of the present disclosure;

fig. 6 is a flowchart of a method for detecting a lens position according to an embodiment of the present disclosure;

fig. 7 is a flowchart of a method for detecting a lens position according to another embodiment of the present application;

fig. 8 is a flowchart of a method for detecting a lens position according to another embodiment of the present application;

fig. 9 is a flowchart of a method for detecting a lens position according to another embodiment of the present application;

fig. 10 is a flowchart of a calibration method for a corresponding relationship between an inductance and an actual coil displacement provided in the embodiment of the present application;

fig. 11 is a flowchart of a method for detecting a lens position according to another embodiment of the present application;

fig. 12 is a flowchart of a calibration method for a correspondence between a current and a lens position according to an embodiment of the present application;

fig. 13 is a schematic structural diagram of a lens position detection system according to another embodiment of the present application;

fig. 14 is a schematic structural diagram of a voice coil motor according to another embodiment of the present application;

FIG. 15 is a flowchart illustrating a method for detecting a lens position according to another embodiment of the present application;

fig. 16 is a flowchart of a lens position detection method according to another embodiment of the present application;

fig. 17 is a flowchart of a method for detecting a lens position according to another embodiment of the present application;

fig. 18 is a flowchart of a lens position detection method according to another embodiment of the present application;

FIG. 19 is a flowchart illustrating a method for detecting lens position according to another embodiment of the present application;

fig. 20 is a schematic structural diagram of an electronic device according to an embodiment of the present application.

Detailed Description

In order to facilitate the technical solutions provided by the present application to be more clearly understood by those skilled in the art, the following first introduces terms in the embodiments of the present application.

The terminology used in the description of the embodiments section of the present application is for the purpose of describing particular embodiments of the present application only and is not intended to be limiting of the present application.

The terms "first", "second", and the like in the description of the present application are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implying any number of technical features indicated.

In the present application, unless expressly stated or limited otherwise, the term "coupled" is to be construed broadly, e.g., "coupled" may be a fixed connection, a removable connection, or an integral part; may be directly connected or indirectly connected through an intermediate.

With the continuous progress of science and technology, the shooting function has become the basic equipment of mobile terminals such as mobile phones, tablet computers, notebook computers, personal Digital Assistants (PDAs), smart wearable devices, and Point of Sales (POS).

Referring to fig. 1A and fig. 1B, fig. 1A is a schematic structural diagram of an electronic device according to an embodiment of the present disclosure; fig. 1B is an exploded view of fig. 1A.

As shown in fig. 1A and 1B, the electronic device will be described by taking a mobile phone as an example. It should be understood that the electronic device of the present embodiment includes, but is not limited to, a mobile phone, and the electronic device may also be a mobile terminal such as the tablet computer, the notebook computer, the PDA, the smart wearable device, or the POS. The embodiment of the present application does not limit the specific type of the electronic device.

As shown in fig. 1A, the electronic apparatus may include a camera module 1, a housing 2, a display panel 3, and a circuit board 4.

The shell 2 encloses the back and the side of establishing at electronic equipment, and display panel 3 installs on shell 2, and display panel 3 and shell 2 enclose into electronic equipment's accommodation space jointly, and module 1 and circuit board 4 of making a video recording all install in this accommodation space.

In addition, a microphone, a loudspeaker, a battery or other devices can be arranged in the accommodating space.

Fig. 1A and 1B show the camera module 1 in the area near the edge of the top of the housing 2. It is to be understood that the position of the camera module 1 is not limited to the position shown in fig. 1A.

As shown in fig. 1B, in some embodiments, the housing 2 may include a rear cover 21 and a middle frame 22, a light hole 211 is formed on the rear cover 21, the camera module 1 may be disposed on the middle frame 22, and the camera module 1 collects external ambient light through the light hole 211 on the rear cover 21.

Wherein, the sensitization face and the light trap 211 of module 1 of making a video recording set up relatively, and external environment light passes the light trap 211 and shines to the sensitization face, and the sensitization face is used for gathering external environment light, and module 1 of making a video recording is used for converting light signal into the signal of telecommunication to realize its shooting function.

Fig. 1B shows that one camera module 1 is provided in the electronic device, and it should be noted that, in practical application, the number of camera modules 1 is not limited to one, and the number of camera modules 1 may also be two or more than two.

When the number of the camera modules 1 is plural, the plurality of camera modules 1 can be arranged arbitrarily in the X-Y plane. For example, the plurality of camera modules 1 are arranged in the X-axis direction, or the plurality of camera modules 1 are arranged in the Y-axis direction.

The camera module 1 includes, but is not limited to, an Auto Focus (AF) module, a wide-angle camera module 1, a telephoto camera module 1, a color camera module 1, or a monochrome camera module 1. The camera module 1 in the electronic device may include any one of the camera modules 1, or include two or more of the camera modules 1.

When the number of the camera modules 1 is two or more, the two or more camera modules 1 may be integrated into one camera module.

As shown in fig. 1B, the camera module 1 may be electrically connected to the circuit board 4. The circuit board 4 is, for example, a main board in the electronic device, and as an embodiment, the camera module 1 may be electrically connected to the main board through an electrical connector.

For example, the camera module 1 is provided with a female socket of the electrical connector, the mainboard is provided with a male socket of the electrical connector, and the female socket is inserted into the male socket so as to realize the electrical connection between the camera module 1 and the mainboard. Wherein, for example, be equipped with the treater on the mainboard, shoot the image through treater control camera module 1. When a user inputs a shooting instruction, the processor receives the shooting instruction and controls the camera module 1 to shoot a shooting object according to the shooting instruction.

Referring to fig. 1C and fig. 1D, fig. 1C is a schematic structural diagram of a camera module provided in the embodiment of the present application; fig. 1D is an exploded view of fig. 1C.

Fig. 1C shows the structure of the camera module 1 in fig. 1B.

As shown in fig. 1C, the camera module 1 of the present embodiment includes a housing 11, a lens 12, and a sensor assembly 15.

The focusing assembly and the driving means are not shown in fig. 1C and 1D.

Specifically, as shown in FIG. 1D, the housing 11 may include an outer frame 111 and a bottom plate 112, the outer frame 111 and the bottom plate 112 together enclose a receiving space of the housing 11. By providing a removable base 112, it is convenient to mount the lens 12, the image sensor assembly 15 and other devices of the camera module 1 within the housing 11.

A side surface of the outer frame 111 facing away from the base plate 112 is provided with a mounting hole 1111, the lens 12 is mounted in the housing 11, and a portion of the lens 12 is exposed to the outside of the housing 11 through the mounting hole 1111. The light incident side of the lens 12 is located outside the housing 11, and the light emergent side of the lens 12 is located inside the housing 11. For example, the light incident side of the lens 12 corresponds to the light-transmitting hole 211 on the rear cover of the electronic device. External ambient light enters the lens 12 from the light-in side of the lens 12 through the light-transmitting hole 211, the lens 12 is composed of, for example, one or more stacked lenses, the optical axis of the lens 12 passes through the center of the lens, the lens condenses the incident light, and the condensed light is emitted from the light-out side of the lens 12.

The image sensor assembly 15 is located on the light-emitting path of the lens 12, for example, the image sensor assembly 15 is located on the light-emitting side of the lens 12, and the optical axis of the lens 12 passes through the center of the image sensor assembly 15. The light emitted from the lens 12 enters the image sensor assembly 15, and the emergent light signal is converted into an electric signal through the photoelectric conversion function of the image sensor assembly 15, so that the imaging function of the camera module 1 is realized.

With continued reference to fig. 1D, the image sensor assembly 15 may be located at the bottom of the housing 11, i.e., the image sensor assembly 15 is disposed proximate the floor 112. For example, the image sensor assembly 15 may be secured to the base plate 112, with the image sensor assembly 15 being supported and positioned by the base plate 112. Specifically, the image sensor assembly 15 may include an image sensor 151 and an electrical connection 152.

The image sensor 151 is located on the light exit side of the lens 12, for example, the optical axis of the lens 12 passes through the center of the image sensor 151. The light emitted from the lens 12 is irradiated to the image sensor 151, and the image sensor 151 photoelectrically converts the light signal into an electrical signal, thereby realizing the imaging function of the camera module 1.

The electrical connection member 152 is used to electrically connect the image sensor 151 to an external circuit, and thus, to control the image sensing operation through the external circuit. Specifically, one end of the electrical connector 152 is connected to the image sensor 151, and the other end of the electrical connector 152 is connected to an external circuit, for example, the other end of the electrical connector 152 is connected to the circuit board 4 in the electronic device. When the user takes a picture, the processor on the circuit board 4 controls the operation of the image sensor 151.

It should be noted that, since the image sensor assembly 15 of the present embodiment can be fixed in the housing 11, taking the example that the image sensor assembly 15 is fixed on the bottom plate 112, the back surface of the image sensor 151 is fixed on the bottom plate 112. Since the image sensor 151 does not need to be moved, the image sensor 151 may be electrically connected to an external Circuit using a flexible electrical connector, or the image sensor 151 and the external Circuit may be connected using an electrical connector 152 having superior strength and rigidity, for example, the Printed Circuit Board 4 (PCB).

The image sensor 151 generates heat during operation, and the heat is collected on the image sensor 151, which may affect the performance of the image sensor 151, and may cause the image sensor 151 to fail to operate normally in a serious case, so that the image sensor 151 needs to be cooled. Therefore, as shown in fig. 1D, a gap may be provided between the heat dissipation surface of the image sensor 151 (the surface of the image sensor 151 facing the base plate 112) and the base plate 112, the gap may be filled with the heat conductive liquid 16, and the heat of the image sensor 151 may be dissipated through the heat conductive liquid 16. Through the heat conduction effect of the heat conduction liquid 16, the heat dissipation efficiency of the image sensor 151 can be improved, the heat dissipation effect of the image sensor 151 is improved, and the working performance of the image sensor 151 is further ensured.

An annular sealing plate 17 may be attached to the bottom plate 112 of the housing 11, and the heat transfer liquid 16 may be located in an area surrounded by the annular sealing plate 17. The heat-conducting liquid 16 is a flowable liquid, and the heat-conducting liquid 16 is confined in an area surrounded by the annular sealing plate 17 by providing the annular sealing plate 17 on the bottom plate 112 of the housing 11. The area surrounded by the annular sealing plate 17 may correspond to a heat radiation surface of the image sensor 151.

A gap can be formed between the annular sealing plate 17 and the heat dissipation surface of the image sensor 151, so that the heat conduction liquid 16 is ensured to be fully contacted with the heat dissipation surface of the image sensor 151, and a certain flowing space is reserved for the heat conduction liquid 16 to expand when heated; further, the surface tension of the heat-conducting liquid 16 in the gap between the surface of the annular seal plate 17 and the heat radiation surface of the image sensor 151 prevents the heat-conducting liquid 16 from overflowing the annular seal plate 17.

With reference to fig. 1D, a plurality of sealing holes 171 may be disposed at intervals on the annular sealing plate 17, and the overflowing heat-conducting liquid 16 is stored in the sealing holes 171 in a sealing manner, so that the heat-conducting liquid 16 is prevented from overflowing out of the annular sealing plate 17. Instead of the seal hole 171, the surface of the annular seal plate 17 may be an uneven corrugated surface, and the extending direction of the corrugations of the corrugated surface may coincide with the extending direction of each side of the annular seal plate 17; alternatively, a plurality of strip-shaped grooves may be provided at intervals on the surface of the annular seal plate 17, and the strip-shaped grooves extend in the contour line direction of the annular seal plate 17.

In some embodiments of the present application, the camera module 1 further includes a focusing assembly 14 (not shown in fig. 1D) disposed within the housing 11 for adjusting the focal length of the lens 12. For example, the focusing assembly may drive the lens 12 to move along the optical axis thereof to achieve the focusing function of the lens 12. A voice coil motor may be used as the focusing assembly 14 in the camera module 1 to adjust the focal length of the lens 12.

When a user holds a portable electronic device (e.g., a mobile phone) for shooting, a shot image is blurred due to hand shake. In contrast, the housing 11 of the image pickup module 1 is provided with a driving device 13, and the driving device 13 drives the lens 12 to move in a plane perpendicular to the optical axis direction thereof. The lens 12 moves in a plane perpendicular to the optical axis thereof, so that the displacement caused by hand shake of a user is compensated, and the quality of the influence of shooting is improved.

In some embodiments of the present application, the camera module 1 further includes a driving assembly 13 (not shown in fig. 1D) disposed in the housing 11 for driving the lens 12 to move in a plane perpendicular to the optical axis direction thereof. A voice coil motor may be used as the driving component 13 in the camera module 1 to drive the lens 12 to move in a plane perpendicular to the optical axis direction.

A Voice Coil Motor (VCM), abbreviated as VCM. A VCM is a device capable of converting electrical energy into mechanical energy.

The VCM can be used as a focusing assembly in the camera module and also can be used as a driving assembly in the camera module.

First, the operation principle of VCM in the related art will be explained.

The basic structure of the VCM includes a coil and permanent magnets, and in some embodiments the VCM may also include structure for fixation.

The VCM has a permanent magnet for providing a magnetic field, and the coil is energized to apply an ampere force to the magnetic field to move the coil. The coil can be controlled to move to a corresponding position by controlling the driving voltage or current of the driving coil, and when the coil and the appointed movable part are relatively fixed, the coil moves to drive the appointed movable part to move to the appointed position.

The VCM is mainly applied to a motion of a small stroke, a high speed, or a high acceleration, and is suitable for a narrow space.

Therefore, the VCM is widely applied to cameras of electronic equipment, and the lens is driven to move through the movement of the coil so as to adjust the position of the lens, realize the automatic focusing of the lens and further enable the electronic equipment to obtain clear images.

Referring to fig. 1E, fig. 1E is a schematic diagram illustrating an operation principle of the voice coil motor.

As shown in fig. 1E, the VCM100 includes a first magnet 101, a second magnet 102, and a coil 103.

The first magnet 101 and the second magnet 102 have opposite unlike magnetic poles, a magnetic field is formed between the first magnet 101 and the first magnet 102, and the coil 103 is located in the magnetic field between the first magnet 101 and the second magnet 102.

When a driving voltage is supplied to the VCM, a current is generated in the coil 103. The driving voltage is typically a dc voltage.

The energized coil 103 receives an ampere force in a magnetic field between the first magnet 101 and the second magnet 102, and the direction of the received force can be determined by the left-hand rule.

As shown in fig. 1E, the direction of the magnetic field between the first magnet 101 and the second magnet 102 is directed from the first magnet 101 to the second magnet 102, and the direction of the current in the coil 103 is shown by the direction of the arrow in fig. 1E. At this time, according to the left-hand rule, it is determined that the coil 103 is subjected to an ampere force to the right, and the coil 103 moves to the right by the ampere force.

By controlling the direct current voltage for driving the coil 103 to move, the coil 103 can be controlled to move to a corresponding position, and the movable part is driven to move to a specified position. That is, different dc voltages can control the coil 103 to move to different positions, and thus drive the moving part to move to different positions.

The electronic device adopts a VCM as a focusing component, and the coil 103 in the VCM is used for driving the lens in the lens 12 to move.

The following describes an assembly structure of the VCM and the lens 12 in the electronic apparatus of fig. 1A.

Referring to fig. 1F, fig. 1F is a schematic structural diagram of an assembly of a voice coil motor and a lens provided in the present application. As shown in fig. 1C and 1F, in one embodiment, the focusing assembly 14 in the lens module 1 is disposed in the housing 11.

As shown in FIG. 1F, in one embodiment, using a VCM as the focusing assembly, the focusing assembly 14 may include a focusing coil 141 and a magnetic member 142. The focusing coil 141 is sleeved on the outer wall of the lens 12, the magnetic member 142 is fixed in the housing 11, and the magnetic member 142 is disposed opposite to the focusing coil 141.

In practical applications, the magnetic member 142 may be fixed on an inner wall of the housing 11, for example, the magnetic member 142 is fixed on an inner side wall of the housing 11 opposite to an outer side wall of the lens 12; alternatively, a fixing structure is provided in the housing 11, the magnetic member 142 is fixed to the fixing structure, and the magnetic member 142 faces the focusing coil 141 on the outer sidewall of the lens 12.

When a user holds the electronic device for shooting, the circuit board 4 controls the focusing coil 141 to work, the focusing coil 141 is electrified to generate an electromagnetic field, a magnetic force is generated between the focusing coil 141 and the magnetic piece 142, the magnetic force drives the focusing coil 141 to move, and the focusing coil 141 drives the lens 12 to move.

For example, the circuit board 4 controls the direction and magnitude of current in the focusing coil 141, adjusts the direction and magnitude of magnetic force generated between the focusing coil 141 and the magnetic member 142, and controls the moving direction and amount of movement of the focusing coil 141, thereby controlling the moving direction and amount of movement of the lens 12 to focus a photographic subject, according to a photographing instruction input by a user.

In order to allow the focusing assembly 14 to smoothly drive the lens 12 to move, a plurality of magnetic members 142 may be provided at intervals along the circumference of the focusing coil 141. For example, one magnetic member 142 is disposed on each of opposite sides of the focusing coil 141; alternatively, four, six, or eight magnetic members 142 are provided at even intervals in the circumferential direction of the focusing coil 141.

For example, the outer sidewall of the lens 12 may be sleeved with the supporting seat 18, and the focusing coil 141 is sleeved on the outer wall of the supporting seat 18. The lens 12 is supported by the support base 18 and the focus coil 141 is fixed.

As shown in fig. 1F, in the above description, the VCM is used as the focusing component, and specifically, the VCM may include a focusing coil and a magnetic member.

In some embodiments of the present application, where a VCM is used as the focusing assembly, embodiments of the present application provide that the VCM includes a magnetic core in addition to a focusing coil and a magnetic member.

In order to facilitate understanding of the technical solutions provided in the embodiments of the present application, the following describes common application scenarios in the embodiments of the present application.

At present, electronic devices such as mobile phones and PADs usually have a shooting function, and can realize automatic lens focusing during shooting.

In the shooting process, the electronic equipment firstly obtains the distance between a shot object and the electronic equipment, namely the object distance of a lens, in a distance measuring mode such as laser distance measurement; and then, determining a direct current voltage for controlling and driving a coil in the VCM to move according to the object distance, and driving the lens to move by using the movement of the coil.

The control of the displacement generated by the coil is realized by controlling the direct-current voltage for driving, so that the lens is controlled to reach a specified position, and the automatic focusing is realized.

There is a correspondence between the object distance and the dc voltage that drives the VCM. In general, the correspondence between the object distance and the dc voltage is prestored in the electronic device.

According to the above description of the operating principle of the VCM, there is a correspondence between the dc voltage for driving the VCM and the displacement generated by the coil.

However, due to the influence of the environment where the lens is located during actual shooting, the displacement actually generated by the movement of the lens driven by the coil may be different from the preset displacement corresponding to the direct-current voltage for driving the VCM.

For example, when a user performs a forward shooting or a forward shooting using the electronic apparatus, the entire lens is inclined with respect to a horizontal plane. The coil can drive the lens to move under the driving of direct-current voltage so as to generate preset displacement, and the coil and the lens can generate certain offset under the action of gravity; or, the temperature during actual shooting can affect the movement of the lens, thereby affecting the displacement of the lens actually generated by the coil.

When the coil drives the actual displacement of the lens and the preset displacement corresponding to the current direct current voltage for driving the VCM is different, the focusing of the camera lens is inaccurate, and the imaging is not clear.

Currently, in order to obtain the displacement actually generated by the coil, and thus the lens position, a Hall sensor (Hall sensor) is generally used. Adding orthogonal magnetic and electric fields to the semiconductor to deflect semiconductor carriers, thereby generating a potential difference across the semiconductor; then, the potential difference is equivalent to the displacement actually generated by the coil, thereby obtaining the lens position.

However, the cost of the hall sensor is high, and in order to avoid the position of the hall sensor, the size of the camera module is increased in the direction of the optical axis and in the direction perpendicular to the optical axis, that is, the hall element occupies more extra space.

Therefore, the above manner of acquiring the lens position greatly increases hardware cost and occupies a large space.

In order to solve the above technical problem, an embodiment of the present application provides a system, a method and a device for detecting a lens position.

By using the technical scheme provided by the application, a magnetic core is embedded in the coil, the controller firstly controls the driving voltage of the coil to be direct current voltage, the coil drives the lens to move under the driving of the direct current voltage, when the coil reaches the first position, namely after the coil stops moving, the controller controls the driving voltage of the coil to be alternating current voltage, then the current of the output end of the coil is obtained, and the position of the lens is determined according to the obtained current of the output end of the coil.

The lens position obtained in the process is the position reached after the coil drives the lens to actually generate displacement, and the influence of factors such as gravity on the coil and the lens is considered in the position, so that the accurate detection of the lens position is realized.

In order to realize clear imaging, the obtained lens position may be compared with a preset position corresponding to a dc voltage for driving the VCM. When the difference exists between the two positions, the lens displacement is compensated according to the difference, so that the lens reaches the preset position.

By adopting the scheme provided by the application, only one magnetic core is nested in the coil of the VCM, so that a Hall sensor is avoided, the hardware cost is reduced, and the occupied space is reduced.

In addition, by adopting the scheme provided by the application, in the process of determining the position of the lens, strong radiation waves can not appear, so that the imaging quality of the electronic equipment can not be influenced.

The embodiment of the application provides a detection system for a lens position.

Referring to fig. 2A, fig. 2A is a schematic structural diagram of a system for detecting a lens position according to an embodiment of the present disclosure.

As shown in fig. 2A, the detection system 200 includes a controller 201 and a detection module 202.

The detection module 202 includes a first magnet 203, a second magnet 204, a coil 205, and a core 206.

The coil 205 is located in a magnetic field formed by the first magnet 203 and the second magnet 204, the relative position of the coil 205 and the lens is fixed, the coil 205 surrounds the outside of the magnetic core 206, and the position of the magnetic core 206 is fixed.

A controller 201 for controlling the driving voltage of the coil to be a first voltage so as to move the coil 205 and the magnetic core 206 relatively; when it is determined that the coil 205 reaches the first position, the driving voltage of the coil 205 is controlled to be a second voltage, the position of the lens is determined by using the current at the output end of the coil 205, the first voltage is a direct current voltage, the second voltage is an alternating current voltage, and effective values of the first voltage and the second voltage are the same.

When the controller 201 supplies a first voltage to the coil 205 as a driving voltage and the energized coil 205 is in a magnetic field formed by the first magnet 203 and the second magnet 204, the coil 205 is moved by an ampere force, and at this time, the coil 205 and the core 206 are moved relatively.

For example, when the direction of the magnetic field between the first magnet 203 and the second magnet 204 is directed from the first magnet 203 to the second magnet 204, the direction of the current in the coil 205 is as indicated by the direction of the arrow in FIG. 2A. At this point, coil 205 moves to the right due to the application of an ampere force to the right, as determined by the left-hand rule.

Since the relative positions of the coil 205 and the lens are fixed, the lens is moved by the movement of the coil 205.

Since the magnetic core 206 is fixed, there is relative movement between the coil 205 and the magnetic core 206 during movement of the coil 205, which results in a change in the inductance of the coil 205.

When the coil 205 reaches the first position, the coil 205 stops moving at this time, that is, the coil 205 is driven by the first voltage to move, and the state where the coil 205 stops moving when reaching the first position is indicated.

Since the inductance of the coil 205 changes, when the controller 201 controls the driving voltage of the coil 205 to be the second voltage of the alternating voltage, the current at the output end of the coil 205 changes.

Since the effective values of the first voltage and the second voltage are the same, when the coil 205 reaches the first position under the driving of the first voltage, that is, the coil 205 stops moving, the driving voltage of the coil 205 becomes the second voltage, and the coil 205 does not continue to move.

The controller 201 is also used to obtain the current at the output of the coil 205.

The current at the output of the coil 205 is related to the inductance of the coil 205, i.e., the displacement caused by the movement of the coil 205; also, since the relative positions of the coil 205 and the lens are fixed, the position of the lens can be determined from the current at the output end of the coil 205.

By adopting the scheme provided by the application, the magnetic core is embedded in the coil of the VCM, the detection on the position of the lens is realized, the Hall sensor is avoided, the hardware cost can be reduced, and the occupied space is reduced.

The controller in the above embodiments of the present Application may be an Application Specific Integrated Circuit (ASIC), a Programmable Logic Device (PLD), a Digital Signal Processor (DSP), or a combination thereof.

The PLD may be a Complex Programmable Logic Device (CPLD), a Field-Programmable Gate Array (FPGA), a General Array Logic (GAL), or any combination thereof, and the embodiments of the present invention are not limited in particular.

One implementation of the controller is described below.

Referring to fig. 2B, the figure is a schematic structural diagram of another lens position detection system according to an embodiment of the present application.

The controller 201 includes a control circuit 2011, a driving circuit 2012 and a sampling circuit 2013.

The control Circuit 2011 is used to control the driving voltage output by the driving Circuit 2012, and the control Circuit 2011 may be, for example, an Imaging Chip (IC) of an electronic device such as a mobile phone.

The driving circuit 2012 is used for outputting a driving voltage to the coil, that is, outputting a first voltage and a second voltage to the coil.

The sampling circuit 2013 is configured to collect a current at an output end of the coil, and transmit a sampling result to the control circuit 2011.

The specific process of the controller controlling the driving voltage of the coil and obtaining the current at the output terminal of the coil is described below.

The controller is used for controlling the driving voltage of the coil and obtaining the current of the output end of the coil.

Referring to fig. 2C, fig. 2C is a diagram illustrating a driving voltage of the coil and a current of the output end of the coil provided by the embodiment of the present application in fig. 2C.

In the upper part of fig. 2C, the horizontal axis represents time, and the vertical axis represents the driving voltage of the coil; in the lower part of fig. 2C, the horizontal axis represents time, and the vertical axis represents the current at the output end of the coil.

Referring to the top of fig. 2C, before time t0, the controller controls the driving voltage of the coil to be a first voltage, that is, a dc voltage V; when the coil reaches the first position, namely when the coil is determined to stop moving, the controller controls the driving voltage of the coil to be the second voltage at the time of t0, namely the driving voltage of the coil is the alternating voltage u at t0-t 1.

The dc voltage V and the ac voltage u have the same effective value.

The movement of the coil causes relative movement between the coil and the core, which causes a change in the inductance of the coil.

Referring to the lower side of fig. 2C, the coil stops moving after time t0, the inductance of the coil no longer changes, and therefore, the current at the output end of the coil is substantially stable at t0-t1 when the driving voltage of the coil is u.

Before time t0, the controller controls the driving voltage of the coil to be the dc voltage V, and the coil cuts the magnetic induction lines when moving under the action of the magnetic field, thereby generating an electromotive force in the coil due to the cut magnetic induction lines.

Therefore, before the time t0, the current at the output end of the coil is not constant, but generally varies depending on the driving voltage of the coil and the motion condition of the coil.

Referring to the bottom of fig. 2C, until time t0, the straight line in the figure does not indicate that the current is constant, but only indicates the presence of the current at the output terminal.

The following description is made with reference to specific implementations.

Referring to fig. 3A, fig. 3A is a schematic structural diagram of a lens position detection system according to another embodiment of the present disclosure.

The system for detecting the lens position provided by the embodiment of the present application is applied to the electronic device shown in fig. 1A, and in particular, is applied to the lens module 1 shown in fig. 1C.

As shown in fig. 3A, the detection system 300 includes a controller 301 and a detection module 302.

The detection module 302 includes a first magnet 303, a second magnet 304, a coil 305, and a magnetic core 306.

The positions of the first magnet 303, the second magnet 304, and the core 306 are fixed. The first magnet 303 and the second magnet 304 have different magnetic poles facing each other.

In one possible implementation, the first magnet 303, the second magnet 304, and the magnetic core 306 may be fixed to a fixing device such as an iron case.

The coil 305 is located in a magnetic field between the first magnet 303 and the second magnet 304, which is formed by the first magnet 303 and the second magnet 304.

The controller 301 is used to provide a driving voltage to the coil 305.

Specifically, the controller 301 provides a dc voltage to the coil 305 as a driving voltage, and the coil 305 drives the lens to move along the optical axis direction under the driving of the dc voltage.

In fig. 3A, the optical axis direction is a direction perpendicular to the magnetic field between the first magnet 303 and the second magnet 304, and parallel to the sheet of fig. 3A. When it is determined that the coil 305 stops moving, that is, when it is determined that the coil 305 reaches the first position, the controller 301 superimposes a preset ac voltage on the dc voltage and supplies the coil 305 with the driving voltage superimposed with the preset ac voltage. The driving voltage on which the predetermined ac voltage is superimposed is the same as the effective value of the dc voltage.

The reason why the driving voltage superimposed with the predetermined ac voltage has the same effective value as the dc voltage is that the coil 305 does not move continuously when driven by the driving voltage superimposed with the predetermined ac voltage.

Specifically, in order that the coil 305 does not move any more under the driving of the driving voltage superimposed with the preset ac voltage, the preset ac voltage may be an ac voltage having a small amplitude.

In the process of moving the coil 305, due to the existence of the damping, the driving action of the ac voltage with the small amplitude on the coil 305 can be offset by the damping, so that the coil 305 does not move any more when driven by the driving voltage superposed with the preset ac voltage.

In order to maintain the coil 305 at the position after the movement is stopped, the controller 301 needs to continuously supply the dc voltage to the coil 605 and keep the effective value of the driving voltage equal to the dc voltage.

In the embodiment of the present application, for the electronic device shown in fig. 1A, the lens module uses a VCM as a focusing component, and the VCM specifically includes a first magnet 303, a second magnet 304, a coil 305, and a magnetic core 306.

Referring to fig. 3B and 3C, fig. 3B is a schematic cross-sectional view illustrating an assembly of a voice coil motor according to an embodiment of the present disclosure.

S is a cross section parallel to the z direction.

And (3) unfolding the complete VCM structure corresponding to the graph in FIG. 3B to obtain a graph in FIG. 3C, wherein the graph in FIG. 3C is an explosion diagram of the graph in FIG. 3B.

Fig. 3B shows a structural section of the assembly of each component in the VCM provided in the embodiment of the present application, and the structure in the VCM corresponds to that in fig. 3C respectively.

In fig. 3B, 307 is a housing of the camera module, and the housing 307 in fig. 3B corresponds to the housing 11 in fig. 1C. Specifically, the housing 307 in fig. 3B shows a circumferential housing portion of the housing 11 in fig. 1C along the focusing coil 141.

In one possible implementation, the coil 305 is a multi-turn wire in a loop shape, as shown in fig. 3B and 3C.

The magnetic core 306 has a hollow structure, and the coil 305 surrounds the magnetic core 306, i.e. the magnetic core 306 is nested in a hollow position inside the coil 305. In order to avoid the extra space occupied by the core 306 while improving the detection accuracy, the coil 305 and the core 306 have an overlapping portion in the direction of the optical axis of the lens.

The specific structure of the VCM assembly and the assembly structure of the VCM as shown in fig. 3B and 3C are merely examples, and it is understood that the specific structure of the VCM assembly and the assembly structure of the VCM are not limited to those shown in fig. 3B and 3C.

In some embodiments, the lens is nested at the hollow structure of the magnetic core 306.

The difference between the VCM provided in this embodiment and the structure assembled by the lens in the lens module and the structure in fig. 1F can be found in that: the core 306 may be disposed between the magnetic member 142 and the lens 12, which is nested within the hollow structure of the core 306.

The controller 301 is also used to obtain the current at the output of the coil 305.

The specific principle of the controller 301 implementing the lens position detection is specifically described below.

When the controller 301 provides a dc voltage to the coil 305, a current flows through the coil 305.

When the energized coil 305 is in the magnetic field between the first magnet 303 and the second magnet 304, the coil 305 moves by receiving an ampere force. The direction of the ampere force experienced by the coil 305 in the magnetic field may be determined according to the left hand rule.

For example, as shown in FIG. 3A, the direction of the magnetic field between the first magnet 303 and the second magnet 304 is from the first magnet 303 to the second magnet 304; for the coil, the direction of the current flow is shown as the arrow pointing in fig. 3A.

From the left-hand rule, the direction of the ampere force received by the coil 305 can be determined. As shown in fig. 3A, the coil 305 is forced to move to the right.

At this time, the coil 305 moves from the initial position and moves the lens. The coil 305 stops after displacement d. For example, coil 305 is now moved to the first position in FIG. 3A. The dc voltage across the coil 305 is different and the corresponding displacement d is different. In practical applications, since the moving direction of the coil is parallel to the optical axis direction, the displacement d of the coil 305 can also represent the position of the coil 305.

In order to maintain the coil 305 at the above position after the movement is stopped, the controller 301 needs to continuously supply the coil 305 with the driving voltage and keep the effective value of the driving voltage unchanged.

There is a corresponding relationship between the dc voltage output by the controller 301 and the displacement of the coil 305 caused by the ampere force movement. For convenience of description, the correspondence relationship is referred to as a correspondence relationship between the dc voltage and the coil displacement.

In a possible implementation manner, in order to reduce the size of the whole camera module, the magnetic core 306 with a hollow structure may be nested in a hollow position inside the coil 305; and the lens is nested in the hollow position of the magnetic core 306, so that the camera module presents a coil 305-magnetic core 306-lens nested structure from the outside to the inside.

Since the core 306 is fixed, there is relative movement between the coil 305 and the core 306 during movement of the coil 305, which results in a change in the inductance of the coil 305.

Upon determining that the movement of the coil 305 has stopped, the controller 301 supplies an alternating voltage to the coil 305. At this time, the controller 301 superimposes a predetermined ac voltage on the dc voltage and outputs the superimposed ac voltage to the coil 305. The parameters of the amplitude, the frequency and the like of the preset alternating voltage are known.

As the inductance of the coil 305 changes, the current at the output of the coil 305 changes when the controller 301 provides an ac voltage to the coil 305.

The controller 301 calculates the inductance of the coil 305 according to the obtained current at the output end of the coil 305, specifically referring to the following formula:

L＝udt/di (1)

in the formula (1), L is the inductance of the coil 305, u is the predetermined ac voltage, t is the time, and i is the current at the output end of the coil 305.

Then, the controller 301 obtains the actual coil displacement corresponding to the inductance according to the correspondence between the inductance and the actual coil displacement obtained through the test calibration in advance.

The above correspondence between the inductance and the actual displacement of the coil is stored in the memory of the electronic device and called when the controller 301 is used.

In some embodiments, the correspondence between the inductance and the actual displacement of the coil may be stored in the form of a data table. For example, it is obtained in advance through test calibration that the actual displacement of the coil is d1 when the inductance is L1, d2, … when the inductance is L2, and dn when the actual displacement of the coil is Ln, the stored corresponding relationships are (L1, d 1), (L2, d 2), …, (Ln, dn).

The actual displacement of the coil obtained through the above process is the displacement generated by the actual movement of the coil 305, and the displacement already covers the displacement of the coil 305 and the lens due to gravity and other factors.

As described above, the coil displacement according to the dc voltage is ideally a corresponding coil displacement that can be generated by controlling the dc voltage. I.e. the displacement of the coil corresponding to the dc voltage does not take into account the offset caused by gravity etc.

The actual displacement of the coil obtained by the controller 301 according to the inductance may be different from the displacement of the coil corresponding to the dc voltage due to the influence of the environment where the lens is located when actually shooting.

The controller 301 can determine the position of the lens based on the actual displacement of the coil obtained by the above process.

Because the relative position of the coil and the lens is not changed, the coil can drive the lens to move when moving. Thus, by determining the actual displacement of the coil, i.e. the displacement of the lens, the position of the lens can be determined.

In another possible implementation manner, since the relative position of the coil and the lens is fixed, after the relative position of the coil and the lens is determined, the displacement of the coil can be converted into the position of the lens, and thus the data table stored in the memory may also be a relationship corresponding to the inductance and the position of the lens.

For example, the lens position is L1 when the inductance is L1, the lens position is L2, … when the inductance is L2, and the lens position is Ln when the inductance is Ln, and the stored corresponding relationships are (L1, L1), (L2, L2), …, (Ln, ln) through test calibration.

From the above description, determining that the coil 305 stops moving, that is, determining that the coil 305 reaches the first position, is a trigger condition for the controller 301 to provide the coil 305 with the driving voltage superimposed with the preset ac voltage.

Two implementations of determining that the coil 305 stops moving, i.e., implementations of determining that the coil 305 reaches the first position, are provided below for this embodiment.

The first implementation mode comprises the following steps:

the controller 301 provides a dc voltage to the coil 305, and determines that the coil 305 stops moving, i.e., determines that the coil 305 reaches the first position, after a preset time period.

In some embodiments, the preset time period corresponds to the dc voltage, and is determined according to a preset time period calibrated in advance and a corresponding relationship between the dc voltage and the preset time period. The above correspondence indicates that the coil 305 is driven by the dc voltage to move, and the coil 305 stops moving within a preset time period corresponding to the dc voltage.

For example, when the dc voltage is V1, the preset time period is T1, which means that the coil 305 stops moving during the preset time period T1 when the coil 305 is driven to move in the above-described magnetic field with the dc voltage V1 during the preset time period T1.

For example, the controller 301 provides the dc voltage V to the coil 305 at time t0, and the controller 301 provides the dc voltage superimposed ac voltage to the coil 305 after a preset time period t to time t 1. The preset time period t corresponding to the dc voltage V is obtained according to a corresponding relationship between the preset time period and the dc voltage, and the corresponding relationship is calibrated in advance.

According to the preset time interval calibrated in advance and the corresponding relation of the direct current voltage, the preset time interval corresponding to the current direct current voltage is determined, and after the controller 301 provides the direct current voltage for the preset time interval, the coil 305 is determined to stop moving.

Because the corresponding relation between the preset time interval and the direct current voltage is calibrated in advance, when the coil is determined to stop moving, only the preset time interval corresponding to the current direct current voltage needs to be obtained, and other extra calculation is not needed, so that the method is simple, convenient and efficient.

The second implementation mode comprises the following steps:

the controller 301 provides a dc voltage to the coil 305, and determines that the coil 305 stops moving, i.e. the coil 305 reaches the first position, when the current at the output terminal of the coil 305 is constant.

When the voltage across the coil 305 is a constant dc voltage, the current of the coil 305 is generally constant.

However, when the energized coil 305 moves in the magnetic fields of the first magnet 303 and the second magnet 304, the magnetic induction line is cut, and an electromotive force is generated in the coil 305 in a direction opposite to the direction of the dc voltage.

Therefore, the current of the coil 305 is not constant during the movement of the coil 305.

When the coil 305 stops moving, the electromotive force generated when the coil 305 cuts the magnetic induction line disappears, and therefore, the current of the coil 305 is kept constant.

Therefore, when the current at the output end of the coil 305 is constant, it can be determined that the coil 305 stops moving, that is, it is determined that the coil 305 reaches the first position.

In a possible implementation manner, after the lens position is determined according to the actual displacement of the coil, the target lens position can be obtained according to the coil displacement determined by the direct-current voltage; and comparing the lens position with the target lens position, and adjusting the lens position to the target lens position according to the difference between the lens position and the target lens position.

The lens position determined according to the actual displacement of the coil refers to the displacement generated by the lens in the actual shooting process, and the displacement covers the displacement of the coil and the lens under the factors such as gravity; the target lens position does not take the offset of the coil and the lens under the factors of gravity and the like into consideration.

The lens position is adjusted to the target lens position according to the difference between the lens position and the target lens position by comparing the lens position and the target lens position, for example, the lens is moved in a compensation manner, and the automatic focusing function of the lens is realized.

In the detection system that this application embodiment provided, the coil is around the magnetic core outside, and the hollow position of coil inside is nested the magnetic core promptly, and the position of magnetic core is fixed. When the coil is controlled to move through the direct-current voltage, the coil and the magnetic core move relatively, and the inductance of the coil is changed.

And when the coil stops moving, the alternating current voltage is superposed with the direct current voltage and then is output to the coil. Calculating to obtain the inductance of the coil through the current at the output end of the coil; then, obtaining the actual displacement of the coil according to the corresponding relation between the inductor and the actual displacement of the coil which are calibrated in advance; since the relative positions of the coil and the lens are fixed, the lens position can be determined from the actual displacement of the coil.

To sum up, the detection system provided by the embodiment of the present application adds the magnetic core in the VCM, and makes the coil surround the magnetic core, thereby realizing the detection of the lens position.

Compared with a mode of realizing lens position feedback by adding a Hall element, the detection system provided by the embodiment of the application has no excessive increase of the size of the device in the direction of the optical axis and the direction perpendicular to the optical axis, so that the structural limitation on the camera module is reduced.

In addition, compared with a Hall element, the magnetic core is low in cost, and the detection system provided by the embodiment of the application can reduce the cost of devices for detecting the position of the lens.

In the above embodiment, after the inductance of the coil is obtained, the actual displacement of the coil is determined according to the corresponding relationship between the inductance calibrated in advance through testing and the actual displacement of the coil.

The following describes the way of calibrating the corresponding relationship between the inductance and the actual displacement of the coil in detail with reference to the accompanying drawings.

The system for detecting the position of the lens provided by the above embodiment can be used for realizing the following manner of calibrating the corresponding relationship between the inductance and the actual displacement of the coil.

With continuing reference to fig. 3A, the specific structure of the detection system is described with reference to the corresponding description of fig. 3A, and the details of the embodiment of the present application are not repeated herein.

According to the principle of the VCM for moving the movable member, there is a corresponding relationship between the dc voltage for driving the coil 305 to move and the displacement generated by the movement of the coil 305, that is, the corresponding relationship between the dc voltage and the coil displacement.

For an electronic device capable of moving a lens by a VCM, the correspondence between the dc voltage and the coil displacement is prestored.

In some embodiments, the correspondence between the dc voltage and the coil displacement may be stored in the form of a data table.

For example, when the dc voltage is V1, the coil displacement is d '1, when the dc voltage is V2, the coil displacement is d'2, …, and when the voltage value of the dc voltage is Vn, the coil displacement is d 'n, and the stored correspondence relationships are (V1, d' 1), (V2, d '2), …, (Vn, d' n).

For example, when the controller 301 outputs the dc voltage V1 to move the coil 305, the displacement d'1 of the coil driven by the dc voltage V1 can be obtained according to the pre-stored correspondence relationship between the dc voltage and the coil displacement.

After the coil 305 stops moving, the controller 301 outputs a predetermined ac voltage to the coil 305.

The implementation of determining the movement stop of the coil 305 is the same as that described in the above embodiment, and is not described herein again.

During the movement of coil 305, the relative movement between coil 305 and core 306 causes the inductance of coil 305 to change, thereby causing the current at the output of coil 305 to change.

At this time, the current at the output end of the coil 305 is obtained, and the inductance corresponding to the displacement generated by the movement of the coil 305 can be obtained by calculation using the formula (1).

The controller 301 outputs different dc voltages to obtain corresponding inductances when the coil 305 generates different displacements, so as to complete calibration of the corresponding relationship between the inductances and the actual displacements of the coil.

Referring to fig. 3D, fig. 3D is a corresponding relationship diagram of the actual displacement of the inductor and the coil provided in the embodiment of the present application.

In fig. 3D, the horizontal axis represents the inductance obtained through the above process, the vertical axis represents the actual displacement of the coil corresponding to different inductances, and a good positive correlation exists between the actual displacement of the coil and the inductance.

Therefore, the correspondence obtained through the above calibration process can be used to detect the lens position in the above embodiment.

In some embodiments, the corresponding relationship between the inductance and the actual displacement of the coil may be stored in the form of a data table, and the specific manner is as described above, which is not described herein again.

In summary, the method for calibrating the corresponding relationship between the inductance and the actual displacement of the coil provided by the embodiment of the present application can be completed by the detection system for the lens position provided by the above embodiment without additionally adding a structure.

In another possible implementation manner, since the relative positions of the coil and the lens are fixed, the data table stored in the above memory may also be the corresponding relationship between the inductance and the lens position.

In order to calibrate the corresponding relationship between the inductance and the lens position, the inductance of the coil can be obtained by calculating according to the obtained current of the output end of the coil by using the formula (1).

The direct current voltage at the two ends of the control coil drives the lens to move, so that different lens positions are obtained, and the calibration of the corresponding relation between the inductance and the lens positions can be completed.

In the above embodiment, the lens position is determined based on the correspondence of the inductance and the displacement/position.

Another implementation of determining the lens position based on the correspondence between the current and the displacement/position is described below.

The controller 301 outputs a dc voltage to move the coil 305.

When it is determined that the coil 305 stops moving, the controller 301 outputs a direct-current voltage superimposed with an alternating-current voltage to the coil 305.

The direct current voltage is superposed with the alternating current voltage for output, and the effective value of the voltage is kept unchanged.

The implementation manner of determining the stopping of the coil 305 is the same as that described in the above embodiment, and is not described herein again.

Since the core 306 is fixed, there is relative movement between the coil 305 and the core 306 during movement, resulting in a change in the inductance of the coil 305.

At this time, the inductance of the coil 305 changes, and the current at the output end of the coil 305 changes.

The controller 301 obtains the actual coil displacement corresponding to the current according to the correspondence between the current and the actual coil displacement obtained through the test calibration in advance.

In some embodiments, the current may be the magnitude or frequency of the current at the output of the coil 305 in the above correspondence between the current and the actual displacement of the coil, taking into account the change in the inductance of the coil 305, which may result in a change in the magnitude or frequency of the current at the output of the coil 305.

The correspondence between the current and the actual displacement of the coil may be stored in a memory of the electronic device and recalled when the controller 301 is in use.

In some embodiments, the correspondence between the current and the actual displacement of the coil may be stored in the form of a data table. For example, the actual displacement of the coil is d1 when the current is i1, the actual displacement of the coil is d2, … when the inductance is i2, and the actual displacement of the coil is dn when the current is in, and the corresponding stored relationships are (i 1, d 1), (i 2, d 2), …, (in, dn) through test calibration.

The actual displacement of the coil obtained through the above process is the actual displacement generated by the coil 305, and the displacement already covers the deviation of the coil 305 and the lens due to gravity and other factors; the coil displacement corresponding to the dc voltage is, in an ideal case, a voltage value of the dc voltage is controlled, and the coil displacement corresponding to the dc voltage can be generated, that is, the coil displacement corresponding to the dc voltage does not account for an offset caused by gravity and other factors.

The controller 301 determines the position of the lens based on the actual displacement of the coil obtained by the above process.

In summary, the lens position is determined based on the corresponding relationship between the current and the displacement/position, the current at the output end of the coil can be directly utilized, and the inductance of the coil does not need to be obtained through current calculation, so that the processing process is simplified.

In another possible implementation, since the relative positions of the coil and the lens are fixed, when the relative positions of the coil and the lens are determined, the displacement of the coil can be converted into the position of the lens.

Therefore, the data table stored in the above memory may be a relationship in which the current and the lens position correspond to each other.

For example, it is obtained in advance through test calibration that when the current is i1, the lens position is l1, when the current is i2, the lens position is l2, …, and when the current is in, the lens position is ln, the corresponding relationship stored is (i 1, l 1), (i 2, l 2), …, (in, ln).

In the above embodiment, after the current at the output end of the coil is obtained, the actual displacement of the coil is determined according to the corresponding relationship between the current calibrated in advance through the test and the actual displacement of the coil. The manner of the correspondence between the calibration current and the actual displacement of the coil is specifically described below with reference to the accompanying drawings.

The system for detecting the position of the lens provided by the above embodiment can be used for realizing the following manner of the corresponding relation between the calibration current and the actual displacement of the coil.

With continuing reference to fig. 3A, the specific structure of the detection system is described with reference to fig. 3A, and the embodiments of the present application are not described herein again.

According to the principle of the VCM for moving the movable member, there is a corresponding relationship between the dc power for driving the coil movement and the displacement generated by the coil movement, that is, the corresponding relationship between the dc voltage and the coil displacement.

In an electronic device capable of realizing auto-focusing, the correspondence between the dc voltage and the coil displacement is stored in a memory of the electronic device in order to realize movement of the lens by the VCM.

In some embodiments, the correspondence between the dc voltage and the coil displacement may be stored in the form of a data table. For example, when the voltage value of the dc voltage is V1, the coil displacement is d '1, when the voltage value of the dc voltage is V2, the coil displacement is d'2, …, and when the voltage value of the dc voltage is Vn, the coil displacement is d 'n, and the stored correspondence relationships are (V1, d' 1), (V2, d '2), …, (Vn, d' n).

The controller 301 outputs a dc voltage to drive the coil 305 to move, for example, the controller 301 outputs a dc voltage V1.

According to the pre-stored corresponding relationship between the direct current voltage and the coil displacement, the displacement d'1 generated by the coil under the driving of the direct current voltage V1 can be obtained.

When the movement of the coil 305 is stopped, the controller 301 outputs an alternating voltage superimposed with an alternating voltage to the coil 305.

During the movement of the coil 305, the relative movement between the coil 305 and the core 306 causes the inductance of the coil 305 to change, thereby causing the current at the output of the coil 305 to change.

At this time, the current at the output terminal of the coil 305 is obtained.

The controller 301 obtains the current of the coil 305 when the coil generates different displacements by outputting different direct-current voltages, and thus, the calibration of the corresponding relationship between the current and the actual displacement of the coil can be completed.

In some embodiments, the corresponding relationship between the current and the actual displacement of the coil may be stored in a form of a data table, and the specific manner is described above and is not described herein again.

In summary, the manner of calibrating the corresponding relationship between the current and the actual displacement of the coil provided by the embodiment of the present application can be completed by the system for detecting the lens position provided by the above embodiment, without adding an additional structure.

In another possible implementation manner, the data table stored in the above memory may also be a correspondence between the current and the lens position.

Because the relative position of the coil and the lens is not changed, the coil can drive the lens to move when moving. Thus, by determining the actual displacement of the coil, i.e. the displacement of the lens, the lens position can be determined.

In order to calibrate the corresponding relationship between the current and the lens position, the direct-current voltage at the two ends of the coil is controlled, so that the current of the output end of the corresponding coil can be obtained when the coil drives the lens to move to obtain different lens positions, and the calibration of the corresponding relationship between the current and the lens position can be completed.

The technical scheme provided by the application can be applied to the correction of the optical axis deviation of the lens in the electronic equipment besides being applied to the scene of automatic focusing of the lens of the electronic equipment in the embodiment.

Referring to fig. 4, fig. 4 is a schematic structural diagram of a lens position detection system according to another embodiment of the present disclosure.

The direction along the optical axis is referred to as the z-axis direction, and the directions perpendicular to the optical axis are the x-axis direction and the y-axis direction, respectively.

In the above embodiments, the detection system applied to the lens position in the scene of the electronic device lens auto-focusing is used to detect the lens position along the optical axis direction, i.e. the z-axis direction.

In order to correct the optical axis deviation of the lens in the electronic device, the detection system in the embodiment of the present application is used to detect the position of the lens perpendicular to the optical axis direction, that is, the x-axis direction and/or the y-axis direction.

Detection system 400 includes controller and detection module, and wherein, the detection module includes first magnetite, second magnetite, coil, magnetic core.

The coil is positioned in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and the lens is fixed, the coil surrounds the outer part of the magnetic core, and the position of the magnetic core is fixed;

the controller is used for controlling the driving voltage of the coil to be a first voltage, when the coil is determined to reach the first position, the driving voltage of the coil is controlled to be a second voltage, the current of the output end of the coil is used for determining the displacement of the coil, the position of the lens is determined according to the displacement of the coil, the first voltage is a direct current voltage, the second voltage is an alternating current voltage, and the effective values of the second voltage and the first voltage are the same.

For a specific structure of the detection system, reference is made to the corresponding description in fig. 3A, and details of the embodiment of the present application are not repeated herein.

The present embodiment is described herein by taking an example in which the detection system is used to detect the lens position in the y-axis direction.

When the controller controls the driving voltage of the coil to be a first voltage, i.e., a dc voltage, the coil drives the lens 401 to move along the y direction. As shown in fig. 4, the coil drives the lens 401 to move along the y direction, and the movement displacement is d. In fig. 4, the moved shot is indicated by a dashed box below the shot 401. At this time, the optical axis direction of the lens 401 moves from the first optical axis position to the second optical axis position.

From the above description, it can be understood that the displacement of the coil to move the lens 401 corresponds to the first voltage.

When the coil stops moving, the controller outputs alternating voltage superposed with the alternating voltage to the coil.

The controller is further configured to obtain a current at the output end of the coil, and obtain the position of the lens according to the obtained current, and the specific principle is described above.

Since the difference between this embodiment and the above embodiments is that the coil drives the lens to generate displacement in different directions, the specific principle of the detection system provided in this embodiment for detecting the position of the lens in the y-axis direction is not described in detail.

The embodiments of the present application do not limit the magnetic core to have a hollow structure, for example, the magnetic core may also have a solid structure.

It can be understood that the magnetic core is nested in the hollow position inside the coil, so that when the coil moves, relative movement exists between the coil and the magnetic core, and the detection of the position of the lens in the y-axis direction can be completed.

The detection system in the embodiment of the present application is based on the basic principle of the x-direction lens position detection, similar to that described above for the y-direction, will not be described in detail here.

Similar to the description in the above embodiments, in some embodiments, in order to implement detection of a lens position in a scene of correcting an optical axis shift, in a memory of an electronic device, one of a correspondence relationship of an inductance and an actual displacement of a coil, a correspondence relationship of an inductance and a lens position, a correspondence relationship of a current and an actual displacement of a coil, or a correspondence relationship of a current and a lens position is stored.

The actual moving distance of the coil is determined according to the corresponding relationship, so as to determine the lens position, or the implementation manner of determining the lens position directly according to the relationship is explained in the above embodiments, and is not described herein again.

Similarly to the description in the above embodiments, the implementation of calibration of the corresponding relationship between the inductance and the actual displacement of the coil, the corresponding relationship between the inductance and the lens position, the corresponding relationship between the current and the actual displacement of the coil, or the corresponding relationship between the current and the lens position has also been described in the above embodiments, and is not described herein again.

In summary, in order to realize the lens auto-focusing function, the electronic device usually includes a VCM. The detection system that this application embodiment provided, in order to realize correcting the skew of camera lens optical axis, increase the magnetic core in VCM to make the magnetic core nestification in the hollow position of coil, realize the detection to the camera lens position.

Compared with a mode of realizing lens position feedback by adding a Hall element, the detection system provided by the embodiment of the application has no excessive increase of the size of the device in the direction of the optical axis, so that the structural limitation on the camera module is reduced.

In addition, compared with a Hall element, the magnetic core is low in cost, and the detection system provided by the embodiment of the application can reduce the cost of a device for detecting the position of the lens.

Based on the lens position detection system provided by the above embodiment, the embodiment of the present application further provides a voice coil motor, which is specifically described below with reference to the accompanying drawings.

Referring to fig. 5, fig. 5 is a schematic structural diagram of a voice coil motor according to an embodiment of the present disclosure.

As shown in fig. 5, the voice coil motor 500 includes a first magnet 501, a second magnet 502, a coil 503, and a core 504.

The coil 503 is located in a magnetic field formed by the first magnet 501 and the second magnet 502, the relative position of the coil 503 and the lens is fixed, the coil 503 surrounds the outside of the magnetic core 504, and the position of the magnetic core 504 is fixed.

The coil is used for generating displacement corresponding to the external driving voltage when the external driving voltage is applied.

In contrast to the moving coil VCM, which is common in electronic devices at present, the voice coil motor according to the embodiment of the present application nests a fixed magnetic core 504 in the coil.

The structural schematic diagram of each component of the voice coil motor 500 and the sectional structural diagram of the voice coil motor 500 assembly provided in the embodiment of the present application are shown in fig. 3B and 3C.

The present embodiment provides a structure for assembling a VCM and a lens in a lens module, which is different from the structure in fig. 1F in that: a fixed magnetic core is nested within the coil and may be disposed between the magnetic member 142 and the lens 12, which is nested within the hollow structure of the magnetic core.

Referring to the above description of the VCM principle in the embodiment, when the coil 503 is driven by a dc voltage, the coil 503 and the core 504 move relatively.

When the voice coil motor 500 is used to move a movable component, such as a lens, the relative position between the coil 503 and the lens is fixed, and the lens can be moved by the movement of the coil 503, so as to adjust the position of the lens.

When the coil 503 is driven by the dc voltage to move to the first position, the driving voltage for controlling the coil 503 becomes an ac voltage having the same effective value as the dc voltage.

At this time, the inductance of the coil 503 is changed by the relative movement between the coil 503 and the core 504, and the displacement of the coil 503 and thus the position of the lens can be determined by the current at the output end of the coil 503.

The specific principle of the foregoing implementation has been described in the foregoing embodiments, and details of this embodiment are not described herein again.

In conclusion, the voice coil motor provided by the embodiment of the application can be used for adjusting and determining the position of the lens, and a Hall sensor is not used, so that the hardware cost can be reduced, and the occupied space can be reduced.

In one possible implementation, the magnetic core 504 may have a hollow structure.

When the vcm 500 is used in a camera module, the lens can be nested in the hollow structure of the core 504. Since the coil 503 surrounds the magnetic core 504, at this time, the lens module has a structure of nesting the coil 503-the magnetic core 504-the lens from the outside to the inside, which can reduce the size of the whole camera module.

The embodiment of the application also provides a method for detecting the position of the lens, which is applied to the detection module in the embodiment.

The detection module comprises a first magnet, a second magnet, a coil and a magnetic core, wherein the coil is located in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and a lens is fixed, the coil surrounds the outside of the magnetic core, and the position of the magnetic core is fixed. The following detailed description is made with reference to the accompanying drawings.

Referring to fig. 6, fig. 6 is a flowchart of a method for detecting a lens position according to an embodiment of the present disclosure.

The detection method comprises S101-S103.

S101, controlling the driving voltage of the coil to be a first voltage so as to enable the coil and the magnetic core to move relatively, wherein the first voltage is a direct-current voltage;

s102, when the coil reaches the first position, controlling the driving voltage of the coil to be a second voltage, wherein the second voltage is an alternating voltage, and the effective values of the first voltage and the second voltage are the same;

and S103, determining the position of the lens by using the current of the output end of the coil.

When the driving voltage of the control coil is a first voltage and the first voltage is a direct current voltage, the coil is moved by the action of an ampere force when the energized coil is in a magnetic field formed by the magnet.

Because the relative position of the coil and the lens is fixed, the lens is driven to move by the movement of the coil.

Since the core is fixed, there is relative movement between the coil and the core during movement of the coil, which results in a change in the inductance of the coil.

When the coil reaches the first position, the coil stops moving, that is, the coil reaches the first position and stops moving under the driving of the first voltage.

Since the inductance of the coil changes, when the driving voltage of the control coil is a second voltage, that is, an alternating voltage having the same effective value as the first voltage, the current at the output end of the coil changes.

Since the current at the output end of the coil changes with the change of the inductance of the coil, the inductance of the coil is related to the displacement of the coil, and the relative positions of the coil and the lens are fixed, the position of the lens can be determined according to the current at the output end of the coil.

By adopting the scheme provided by the application, the magnetic core is nested in the coil of the VCM, the detection on the position of the lens is realized, the Hall sensor is avoided, the hardware cost can be reduced, and the occupied space is reduced.

In addition, by adopting the scheme provided by the application, in the process of determining the position of the lens, the wave with strong radiation can not appear, so that the imaging quality of the electronic equipment can not be influenced.

The embodiment of the present application further provides another method for detecting a lens position, which is applied to the detection module in the above embodiment, that is, the detection module in the embodiment corresponding to fig. 2.

The detection module comprises a first magnet, a second magnet, a coil and a magnetic core, wherein the coil is located in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and a lens is fixed, the coil surrounds the outside of the magnetic core, and the position of the magnetic core is fixed.

The following detailed description is made with reference to the accompanying drawings.

Referring to fig. 7, fig. 7 is a flowchart of a method for detecting a lens position according to another embodiment of the present application.

The method includes S201-S206.

S201, outputting direct current voltage to move the coil so as to enable the coil and the magnetic core to move relatively.

The principle of the relative movement between the coil and the core is described in the above embodiments, and is not described herein again.

And S202, when the coil is determined to stop moving, superposing preset alternating voltage on the direct current voltage for outputting.

And superposing a preset alternating voltage on the direct current voltage for outputting, wherein the effective value of the voltage is kept unchanged.

For the implementation manner of determining the coil movement stop in S202, which has been described in the above embodiments, the embodiments of the present application are not described herein again.

And S203, detecting the current of the output end of the coil.

In S203, the inductance of the coil changes due to the relative movement between the coil and the core during the movement of the coil. When an alternating voltage is applied to the coil, the current at the output of the coil changes.

And S204, calculating the inductance of the coil according to the detected current.

In some embodiments, the manner in which the inductance of the coil is calculated from the current may be implemented according to equation (1). The specific implementation manner is described in the foregoing embodiments, and details of the embodiments of the present application are not described herein again.

And S205, obtaining the actual displacement of the coil according to the corresponding relation between the pre-calibrated inductance and the actual displacement of the coil.

In some embodiments, the corresponding relationship between the actual displacement of the inductor and the actual displacement of the coil may be stored in a form of a data table, and the specific manner is described in the above embodiments, and is not described herein again.

And S206, determining the position of the lens according to the actual displacement of the coil.

The effects that can be achieved by the steps in the above method and the implementation manners corresponding to the steps have been described in the above embodiments, and therefore, the embodiments of the present application are not described herein again.

Since the positions of the coil and the lens are fixed, after the inductance of the coil is obtained in S204, the corresponding relationship according to which the lens position is determined may also be the corresponding relationship between the inductance and the lens position.

In another possible implementation manner, after the inductance of the coil is obtained in S204, the position of the lens is obtained according to a pre-calibrated correspondence between the inductance and the lens position.

The corresponding relation between the inductance and the lens position is calibrated in advance, the lens position can be directly obtained according to the inductance without determining the actual displacement of the coil at first and then determining the lens position through the actual displacement of the coil, and therefore the processing process can be simplified.

In the above embodiment, determining that the coil movement is stopped is the triggering condition for superimposing the ac voltage output on the dc voltage. In order to determine that the coil movement is stopped, that is, to determine that the coil 305 reaches the first position, the embodiment of the present application provides the following two implementations, please refer to fig. 8 and 9.

Referring to fig. 8, fig. 8 is a flowchart of a method for detecting a lens position according to another embodiment of the present application.

The method is applied to the detection module in the embodiment corresponding to fig. 2, and the method includes S301-S306.

S301, outputting direct current voltage to move the coil so as to enable the coil and the magnetic core to move relatively.

And S302, after the direct-current voltage is output for a preset time period, superposing a preset alternating-current voltage on the direct-current voltage for outputting, wherein the preset time period is obtained according to a preset time period calibrated in advance and the corresponding relation of the direct-current voltage.

In S302, a preset ac voltage output is superimposed on the dc voltage, and the effective value of the voltage remains unchanged.

The preset time period corresponds to the direct-current voltage and is determined according to the corresponding relation between the preset time period and the direct-current voltage which are calibrated in advance. The above correspondence indicates that the coil is driven by the dc voltage to move, and the coil stops moving within a preset time period corresponding to the dc voltage.

And S303, detecting the current of the output end of the coil.

And S304, calculating the inductance of the coil according to the detected current.

S305, obtaining the actual displacement of the coil according to the corresponding relation between the inductor and the actual displacement of the coil which are calibrated in advance.

And S306, determining the position of the lens according to the actual displacement of the coil.

The effects that can be achieved by the steps in the method and the implementation manners corresponding to the steps have been described in the above embodiments, and are not described herein again in this application embodiment.

And determining the preset time period corresponding to the current direct-current voltage according to the corresponding relation between the preset time period and the direct-current voltage calibrated in advance, and determining that the coil stops moving after the direct-current voltage lasts for the preset time period.

Since the positions of the coil and the lens are fixed, after the inductance of the coil is obtained in S304, the corresponding relationship according to which the lens position is determined may also be the corresponding relationship between the inductance and the lens position.

In another possible implementation manner, after the inductance of the coil is obtained in S304, the position of the lens is obtained according to a pre-calibrated correspondence between the inductance and the lens position.

Referring to fig. 9, fig. 9 is a flowchart of a lens position detection method according to another embodiment of the present application.

The method is applied to the detection module in the embodiment corresponding to fig. 2, and includes S401-S406.

S401, outputting direct current voltage to move the coil so that the coil and the magnetic core move relatively.

S402, detecting the current of the output end of the coil.

And S403, when the current at the output end of the coil is not changed, superposing a preset alternating voltage on the direct current voltage for outputting.

When the voltage across the coil is a constant dc voltage, the current of the coil is a constant dc current.

However, when the energized coil moves in the magnetic fields of the first and second magnets, the magnetic induction wire is cut, and an electromotive force is generated in the coil in a direction opposite to the direction of the dc voltage.

Thus, the current of the coil is not constant during the movement of the coil.

When the coil stops moving, the electromotive force generated by the coil cutting the magnetic induction line disappears, so that the current of the coil does not change any more. Therefore, when the current at the output end of the coil is constant, it can be determined that the coil stops moving.

In some embodiments, when the magnitude of the current at the coil output remains constant, the current is characterized as constant.

And S404, calculating the inductance of the coil according to the detected current.

And S405, obtaining the actual displacement of the coil according to the corresponding relation between the pre-calibrated inductance and the actual displacement of the coil.

And S406, determining the position of the lens according to the actual displacement of the coil.

The coil may be subject to unexpected motion during movement due to other factors. For example, during the movement of the coil, the direct-current voltage for driving the movement of the coil is accidentally fluctuated, so that the coil is irregularly moved.

In this case, the above-described manner of determining the stop of the movement of the coil can reduce the occurrence of erroneous results due to accidental situations.

Since the positions of the coil and the lens are fixed, after the inductance of the coil is obtained in S405, the corresponding relationship according to which the lens position is determined may also be the corresponding relationship between the inductance and the lens position.

In another possible implementation manner, after the inductance of the coil is obtained in S405, the position of the lens is obtained according to the corresponding relationship between the inductance and the lens position calibrated in advance.

Further, in order to obtain the corresponding relationship between the inductance and the actual displacement of the coil in S205, the embodiment of the present application further provides a calibration method for the corresponding relationship between the inductance and the actual displacement of the coil, and the method is applied to the detection module in the embodiment corresponding to fig. 2.

Referring to fig. 10, fig. 10 is a flowchart of a calibration method for a corresponding relationship between an inductance and an actual coil displacement provided in the embodiment of the present application.

The calibration method comprises S501-S505.

S501, outputting direct current voltage to move the coil so that the coil and the magnetic core move relatively.

And S502, when the coil is determined to stop moving, superposing preset alternating current voltage on the direct current voltage for outputting.

S503, detecting the current of the output end of the coil.

And S504, calculating the inductance of the coil according to the detected current.

And S505, obtaining the corresponding relation between the inductance and the actual displacement of the coil based on the corresponding relation between the pre-calibrated direct-current voltage and the coil displacement according to the inductance of the coil.

According to the principle that the VCM moves the lens, there is a corresponding relationship between the dc voltage used for driving the coil movement and the displacement generated by the coil movement, that is, the corresponding relationship between the dc voltage and the coil displacement.

And when the coil stops moving, outputting a preset alternating voltage to the coil.

During the movement of the coil, the relative movement between the coil and the core causes the inductance of the coil to change, thereby causing the current at the output end of the coil to change.

At this time, the current at the output end of the coil is obtained, and the inductance of the coil can be obtained by calculating according to the formula (1).

By outputting different direct-current voltages, the corresponding inductance when the coil generates different displacements is obtained, and the calibration of the corresponding relation between the inductance and the actual displacement of the coil can be completed.

The effects that can be achieved by the steps in the method and the implementation manners corresponding to the steps have been described in the above embodiments, and are not described herein again.

In summary, the calibration method for the corresponding relationship between the inductance and the actual coil displacement provided by the embodiment of the present application can be applied to the detection module in the detection system for the lens position provided by the above embodiment, and it is not necessary to additionally add a structure for completing the calibration process.

In a possible implementation manner, since the relative positions of the coil and the lens are fixed, the corresponding relationship between the inductance and the lens position can also be calibrated.

The embodiment of the application also provides another method for detecting the position of the lens, and the method determines the position of the lens based on the corresponding relation between the current and the actual displacement of the coil so as to directly utilize the current at the output end of the coil without calculating the inductance of the coil through the current, thereby simplifying the processing process.

Referring to fig. 11, fig. 11 is a flowchart of a method for detecting a lens position according to another embodiment of the present application.

The method is applied to the detection module in the embodiment corresponding to fig. 2, and includes S601-S604.

S601, outputting a dc voltage to move the coil, so that the coil and the core move relatively.

And S602, when the coil is determined to stop moving, superposing preset alternating current voltage on the direct current voltage for outputting.

And S603, detecting the current of the output end of the coil.

And S604, obtaining the position of the lens according to the detected current and the corresponding relation between the pre-calibrated current and the position of the lens.

It is to be understood that the method of determining the lens position based on the correspondence relationship between the current and the actual displacement of the coil is similar to the method of determining the lens position based on the correspondence relationship between the inductance and the actual displacement of the coil in the above-described embodiment.

Since the positions of the coil and the lens are fixed, in another possible implementation manner, after the current at the output end of the coil is obtained in S603, the corresponding relationship according to which the position of the lens is determined may also be a process of obtaining the actual displacement of the coil according to the current at the output end of the coil, and then determining the position of the lens according to the actual displacement of the coil.

Further, in order to obtain the corresponding relationship between the current and the lens position in S604, an embodiment of the present application further provides a calibration method for the corresponding relationship between the current and the lens position, and the method is applied to the detection module in the embodiment corresponding to fig. 2.

Referring to fig. 12, fig. 12 is a flowchart of a calibration method for a correspondence between a current and a lens position according to an embodiment of the present application.

The calibration method comprises S701-S704.

And S701, outputting direct current voltage to move the coil so as to enable the coil and the magnetic core to move relatively.

And S702, when the coil is determined to stop moving, superposing preset alternating current voltage on the direct current voltage for outputting.

And S703, detecting the current of the output end of the coil.

S704, obtaining a corresponding relation between the current and the lens position according to the current of the output end of the coil and based on a corresponding relation between the pre-calibrated direct-current voltage and the coil displacement.

And when the coil stops moving, outputting alternating voltage superposed with the alternating voltage to the coil.

During the movement of the coil, the relative movement between the coil and the magnetic core causes the inductance of the coil to change, thereby causing the current at the output end of the coil to change.

The controller outputs different direct current voltages to obtain corresponding currents when the coil generates different displacements, and calibration of the corresponding relation between the currents and the actual displacement of the coil can be completed.

In summary, the calibration method for the correspondence between the current and the lens position provided in the embodiment of the present application can be applied to the detection module in the detection system for the lens position provided in the above embodiment, without adding an additional structure for completing the calibration process.

In a possible implementation manner, since the relative positions of the coil and the lens are fixed, the corresponding relationship between the inductance and the actual displacement of the coil can be calibrated.

The structure of the VCM in the above embodiments is implemented based on the moving-coil VCM principle, that is, in the VCM, the positions of the two magnets are fixed, and in the case that the relative positions of the coil and the lens are fixed, the coil is moved by applying an ampere force to the magnetic fields of the two magnets to drive the lens to move, so as to change the position of the lens.

In addition, the embodiment of the application also provides a detection system for the lens position, and the detection system is realized based on the moving magnetic VCM principle.

The principle of a moving-magnet VCM is first described here.

A moving-magnet VCM includes a coil and a magnetic component. Unlike a moving coil VCM, in a moving magnet VCM, the coil is fixed and the magnetic member is movable.

When the coil provides direct current driving voltage, the current passing through the coil can generate a magnetic field around the coil, and the magnetic component is positioned in the magnetic field and is forced to move under the action of the magnetic field.

Because the relative position of the magnetic part and the lens is fixed, the lens is driven to move by the movement of the magnetic part, so that the position of the lens is changed.

The moving-coil VCM can be used to adjust the position of the lens along the optical axis direction and the direction perpendicular to the optical axis, that is, the moving-coil VCM can be applied to an auto-focus scene of the lens and a correction scene of the optical axis deviation of the lens.

For the moving-magnet VCM, the position of the lens is usually adjusted in a direction perpendicular to the optical axis, that is, the moving-magnet VCM is usually applied to a scene for correcting the optical axis deviation of the lens.

As shown in fig. 1C, the camera module 1 uses a VCM as a driving component for driving the lens 12 to move in a plane perpendicular to the optical axis direction.

When the VCM is applied to a correction scene of lens optical axis deviation, due to the influence of the actual environment of the lens, the magnetic component drives the lens to move to actually generate displacement, and the displacement may be different from the preset displacement corresponding to the direct-current voltage for driving the VCM.

For example, when a dc driving voltage is applied to the coil, the magnetic member drives the lens to move to generate a predetermined displacement. When the whole lens is in a state of being inclined relative to the horizontal plane, the magnetic component and the lens generate certain offset under the action of gravity besides the preset displacement; or, the temperature during actual shooting may affect the movement of the lens, thereby affecting the displacement of the lens actually generated by the magnetic component.

When the magnetic component drives the actual lens displacement and the preset displacement corresponding to the current direct current voltage driving the VCM is different, the correction of the lens optical axis deviation is inaccurate.

Based on this, this application still provides a detection system of camera lens position.

The following is a system for detecting a lens position according to another embodiment of the present application.

Referring to fig. 13, fig. 13 is a schematic structural diagram of a system for detecting a lens position according to another embodiment of the present application.

The inspection system 600 includes a controller 601 and an inspection module 602.

The detection module 602 includes a magnetic component 603, a coil 604 and a magnetic core 605, the coil 604 is wound outside the magnetic core 605, and the relative positions of the magnetic component 603 and the magnetic core 605 are fixed.

The controller 601 is configured to control a driving voltage of the coil 604 to be a first voltage, where the first voltage is a dc voltage, so as to cause the magnetic member 603 and the coil 604 to move relatively.

Since the relative positions of the magnetic member 603 and the core 605 are fixed, the core 605 and the coil 604 are relatively moved.

Since the relative positions of the magnetic component 603 and the lens are fixed, the lens can be moved by the movement of the magnetic component 603.

When it is determined that the magnetic member 603 reaches the first position, that is, it is determined that the magnetic member 603 stops moving, the controller 601 controls the driving voltage of the coil 604 to be a second voltage, which is an alternating voltage, and the effective values of the first voltage and the second voltage are the same.

As shown in fig. 13, the magnetic member 603 moves from the initial position by a distance d to reach the first position.

Since the effective values of the first voltage and the second voltage are the same, when the magnetic member 603 reaches the first position, that is, when the magnetic member 603 stops moving, the driving voltage of the control coil 604 becomes the second voltage, and the magnetic member 603 does not continue to move.

The controller 601 is also used to obtain the current at the output of the coil 604.

Since the current at the output of the coil 604 is related to the inductance of the coil 604, i.e. to the displacement of the magnetic part 603 with respect to the movement of the coil 604; since the relative positions of the magnetic member 603 and the lens are fixed, the position of the lens can be determined from the current at the output end of the coil 604.

By adopting the scheme provided by the application, the magnetic core is nested in the coil of the VCM, the detection on the position of the lens is realized, the Hall sensor is avoided, the hardware cost can be reduced, and the occupied space is reduced. In addition, by adopting the scheme provided by the application, in the process of determining the position of the lens, the wave with strong radiation can not appear, so that the imaging quality of the electronic equipment can not be influenced.

The following description is made with reference to specific implementations.

Since the magnetic field generated by the energized coil exists inside and outside the coil, the magnetic member may be located inside or outside the coil in order to move the magnetic member by the magnetic field.

In the following description, a magnetic member is described as an example of being located inside a coil. When the magnetic part is located inside the coil, that is, when the coil surrounds the outside of the magnetic part, the size of the VCM can be reduced.

Since the magnetic field generated by the energized coil exists inside and outside the coil, the magnetic component may be in the magnetic field generated by the coil and move when subjected to a force, although outside the coil.

Therefore, when the magnetic member is located outside the coil, the principle of determining the lens position is the same as when the magnetic member is located inside the coil, and thus, the description thereof is omitted.

Referring to fig. 13, fig. 13 is a schematic structural diagram of a lens position detection system according to another embodiment of the present disclosure.

The system for detecting the lens position provided by the embodiment of the application is applied to the electronic device shown in fig. 1A.

As shown in fig. 13, the detection system 700 includes a controller 601 and a detection module 602.

The detection module 602 includes a magnetic component 603, a coil 604, and a magnetic core 605.

The coil 604 surrounds the core 605, the relative positions of the magnetic component 603 and the core 605 are fixed, and the magnetic component 603 is located inside the coil 604.

The controller 601 supplies a driving voltage to the coil 604.

Specifically, the controller 601 first provides the coil 604 with a dc voltage as a driving voltage.

The current in the coil 604 generates a magnetic field around the coil 604 by the driving of the dc voltage, so that the magnetic member 603 located in the magnetic field moves.

Because the relative positions of the magnetic component 603 and the lens are fixed, when the magnetic component 603 moves, the lens is driven to move.

Since the relative positions of the magnetic component 603 and the magnetic core 605 are fixed and the relative positions of the magnetic component 603 and the lens are fixed, in one possible implementation, the magnetic core 605 may be located on the lens.

In the embodiment of the present application, for the electronic device shown in fig. 1A, the lens module uses a VCM as a driving component, and specifically includes a magnetic component 603, a coil 604, and a magnetic core 605.

The difference between the cross section of the VCM assembly provided in the embodiment of the present application and the cross section schematic diagram of the VCM assembly in fig. 3B is that:

in fig. 3B, the positions of the first magnet 303, the second magnet 304, and the magnetic core 306 are fixed, and the magnetic core 306 is nested in a hollow position inside the coil 305; with the VCM provided in this embodiment, the coil 604 is wound around the core 605, the relative positions of the magnetic component 603 and the core 605 are fixed, and the magnetic component 603 is located inside the coil 604.

In some embodiments, the lens is nested at the hollow structure of the core 306.

The VCM provided by the embodiment of the application can be used as a driving component in a lens module, and the VCM provided by the embodiment of the application can be assembled with a lens in the lens module and is used for driving the lens to move in a plane vertical to the optical axis direction of the lens.

Since the magnetic field generated by the energized coil 604 exists inside and outside the coil 604, the magnetic member 603 located inside the coil 604 is in the magnetic field generated by the coil 604 and moves when force is applied.

When it is determined that the coil 604 stops moving, that is, when it is determined that the coil 305 reaches the first position, the controller 601 superimposes a preset ac voltage on the dc voltage and supplies the coil 604 with the driving voltage superimposed with the ac voltage. The driving voltage on which the predetermined ac voltage is superimposed is the same as the effective value of the dc voltage.

The reason why the driving voltage superimposed with the predetermined ac voltage and the dc voltage have the same effective value is that the magnetic member 603 does not move when the coil 604 is driven by the driving voltage superimposed with the predetermined ac voltage after the magnetic member 603 stops moving.

Specifically, in order that the magnetic member 603 does not move any more when the coil 604 is driven by the driving voltage superimposed with the predetermined ac voltage, the predetermined ac voltage may be an ac voltage having a small amplitude.

In the process of moving the magnetic component 603, due to the existence of the damping, the force generated by the magnetic field of the coil 604 on the magnetic component 603 can be offset by the damping, so that the magnetic component 603 does not move any more when the coil 604 is driven by the driving voltage superposed with the preset alternating voltage.

In order to maintain the magnetic member 603 at the position after stopping the movement, the controller 601 needs to continuously supply the dc voltage to the coil 604 and keep the effective value of the driving voltage equal to the dc voltage.

Since the coil 604 is fixed, the relative positions of the magnetic component 603 and the core 605 are fixed. Therefore, when the magnetic member 603 moves, the core 605 also moves, resulting in the core 605 moving relative to the coil 604.

The core 605 moves relative to the coil 604 such that the inductance of the coil 604 changes. When the driving voltage superimposed with the preset ac voltage is supplied to the coil 604, the current at the output terminal of the coil 604 changes, that is, the current at the output terminal of the coil 604 can reflect the inductance of the coil 604.

The controller 601 calculates the inductance of the coil 604 according to the obtained current at the output end of the coil 604, which is specifically referred to as the following formula:

L＝udt/di (2)

in the equation (2), L is the inductance of the coil 604, u is the predetermined ac voltage, t is the time, and i is the current at the output terminal of the coil 604.

Therefore, the inductance of the coil 604 and the displacement of the core 605 due to the actual movement of the coil 604 can be obtained from the current at the output end of the coil 604.

Since the relative positions of the magnetic member 603 and the magnetic core 605 are fixed, a displacement of the magnetic member 603 with respect to the actual movement of the coil 604, that is, an actual displacement of the magnetic member can be obtained from the current at the output end of the coil 604.

Then, the controller 601 obtains the actual displacement of the coil corresponding to the inductance according to the corresponding relationship between the inductance and the actual displacement of the magnetic component, which is obtained through the test calibration in advance.

The above correspondence between the inductance and the actual displacement of the magnetic component is stored in the memory of the electronic device and called when the controller 601 is used.

In some embodiments, the correspondence between the inductance and the actual displacement of the magnetic component may be stored in the form of a data table. For example, the actual displacement of the magnetic member is d1 when the inductance is L1, d2, … when the inductance is L2, and dn when the inductance is Ln, the actual displacement of the magnetic member is dn, and the corresponding relationship stored is (L1, d 1), (L2, d 2), …, (Ln, dn) through test calibration.

The actual displacement of the magnetic component obtained through the above process is the displacement actually generated by the magnetic component 603, and the displacement already covers the offset of the magnetic component 603 and the lens due to factors such as gravity.

As described above, the magnetic member displacement according to the dc voltage is ideally a corresponding magnetic member displacement that can be generated by controlling the dc voltage. That is, the displacement of the magnetic member corresponding to the dc voltage does not take into account the offset caused by gravity and the like.

The actual displacement of the magnetic member obtained by the controller 601 according to the inductance may be different from the displacement of the magnetic member corresponding to the dc voltage due to the influence of the environment where the lens is located when actually shooting.

The controller 601 can determine the position of the lens based on the actual displacement of the magnetic member obtained by the above-described process.

Because the relative position of the magnetic part and the lens is fixed, the magnetic part can drive the lens to move when moving. Therefore, by determining the actual displacement of the magnetic member, i.e., the displacement of the lens, the position of the lens can be determined.

In another possible implementation manner, since the relative position of the magnetic component and the lens is fixed, after the relative position of the magnetic component and the lens is determined, the displacement of the magnetic component can be converted into the position of the lens, and thus the data table stored in the above memory may also be a corresponding relationship between the inductance and the position of the lens.

From the above description, determining that the magnetic member 603 stops moving, that is, determining that the coil 305 reaches the first position, is a trigger condition for the controller 601 to supply the coil 604 with the driving voltage superimposed with the preset ac voltage.

The following provides two implementations of determining that the magnetic component 603 stops moving, that is, determining that the magnetic component 603 reaches the first position.

The first implementation mode comprises the following steps:

the controller 601 provides a dc voltage to the coil 604 for a predetermined period of time, and the magnet 603, i.e., the magnet 603, is determined to reach the first position.

In some embodiments, the preset time period corresponds to the dc voltage, and is determined according to a preset time period calibrated in advance and a corresponding relationship between the dc voltage and the preset time period. The above correspondence relationship indicates that when the dc voltage is applied to the coil 305, the magnetic member 603 moves, and the magnetic member 603 stops moving within a predetermined time period corresponding to the dc voltage.

For example, when the dc voltage is V1, the preset time period is T1, which indicates that the magnetic member 603 stops moving during the preset time period T1 when the coil 604 is driven with the dc voltage V1 and the magnetic member 603 moves in the magnetic field generated by the energized coil 604 during the preset time period T1.

For example, the controller 601 supplies the coil 305 with the dc voltage V at time t0, and the controller 601 supplies the coil 604 with the dc voltage superimposed ac voltage after a preset time period t to time t 1. The preset time period t corresponding to the dc voltage V is obtained according to a corresponding relationship between the preset time period and the dc voltage, which is calibrated in advance.

According to the corresponding relation between the preset time interval calibrated in advance and the direct current voltage, the preset time interval corresponding to the current direct current voltage is determined, and after the controller 601 provides the direct current voltage for the preset time interval, the magnetic component 603 is determined to stop moving.

Because the corresponding relation between the preset time interval and the direct current voltage is calibrated in advance, when the magnetic component is determined to stop moving, only the preset time interval corresponding to the current direct current voltage needs to be obtained, and other extra calculation is not needed, so that the method is simple, convenient and efficient.

The second implementation mode comprises the following steps:

the controller provides a first voltage to the coil, and when the current at the output end of the coil is not changed, the magnetic component stops moving, namely the magnetic component reaches a first position.

When the voltage across the coil is a constant dc voltage, the current of the coil is typically a constant current.

However, when a magnetic field is generated around the energized coil, the magnetic member moves in the magnetic field. Since the position of the coil is fixed, relative motion is generated between the coil and the magnetic component, so that the energized coil cuts the magnetic induction lines in the magnetic field generated by the magnetic component, and the coil cuts the magnetic induction lines to generate electromotive force.

Therefore, during the movement of the magnetic member, the coil cuts the electromotive force generated by the magnetic induction wire, so that the current passing through the coil is varied.

When the magnetic component stops moving, the electromotive force generated by the coil cutting the magnetic induction line disappears, so that the current of the coil does not change.

Therefore, when the current at the output end of the coil is constant, it can be determined that the magnetic member stops moving, that is, that the magnetic member reaches the first position.

Unexpected motion may occur due to the magnetic components being affected by other factors during movement. For example, during the movement of the magnetic member, the first voltage across the coil is unexpectedly fluctuated, so that the magnetic member is irregularly moved. In this case, the above-described manner of determining the stop of the movement of the magnetic member can reduce the occurrence of erroneous results due to accidental situations.

In a possible implementation manner, after the lens position is determined according to the actual displacement of the magnetic component, the target lens position can be obtained according to the displacement of the magnetic component determined by the direct-current voltage; and comparing the lens position with the target lens position, and adjusting the lens position to the target lens position according to the difference between the lens position and the target lens position.

The lens position determined according to the actual displacement of the magnetic component refers to the displacement generated by the lens in the actual shooting process, and the displacement covers the displacement of the magnetic component and the lens under the factors of gravity and the like; the target lens position does not take into account the offset of the magnetic component and the lens under the factors of gravity and the like.

By comparing the lens position with the target lens position, the lens position is adjusted to the target lens position according to the difference between the two lens positions, for example, the lens is moved in a compensation manner, so that the optical axis deviation of the lens can be corrected more accurately.

In the detection system provided by the embodiment of the application, the coil is wound outside the magnetic core, and the position of the coil is fixed. When the magnetic component is controlled to move by controlling the driving voltage of the coil to be direct-current voltage, the coil and the magnetic core relatively move due to the fact that the relative position of the magnetic core and the magnetic component is fixed, and the inductance of the coil is changed. And when the magnetic component stops moving, outputting the preset alternating current voltage and the superposed direct current voltage to the coil. Calculating the inductance of the coil according to the current at the output end of the coil; then, obtaining the actual displacement of the magnetic component according to the corresponding relation between the inductance calibrated in advance and the actual displacement of the magnetic component; since the relative positions of the magnetic member and the lens are fixed, the lens position can be determined based on the actual displacement of the magnetic member.

In the above embodiment, after the inductance of the coil is obtained, the actual displacement of the magnetic component is determined according to the correspondence between the inductance calibrated in advance through testing and the actual displacement of the magnetic component.

The following describes in detail the way of calibrating the corresponding relationship between the inductance and the actual displacement of the magnetic component with reference to the accompanying drawings.

The detection system for the lens position provided by the above embodiment can be used for realizing the following manner of calibrating the corresponding relationship between the inductance and the actual displacement of the magnetic component.

With continuing reference to fig. 13, regarding the specific structure of the detection system, reference is made to the corresponding description of fig. 13, and the embodiments of the present application are not described herein again.

According to the principle of the VCM for moving the movable member, there is a corresponding relationship between the dc voltage for driving the coil 604 to generate the magnetic field and the displacement generated by the movement of the magnetic member 603, that is, the dc voltage and the magnetic member displacement.

For an electronic device capable of moving a lens by a VCM, a correspondence between the dc voltage and the displacement of the magnetic member is prestored.

In some embodiments, the correspondence between the dc voltage and the displacement of the magnetic component may be stored in the form of a data table.

For example, when the dc voltage is V1, the magnetic member displacement is d '1, when the dc voltage is V2, the magnetic member displacement is d'2, …, and when the voltage value of the dc voltage is Vn, the magnetic member displacement is d 'n, and the stored correspondence relationships are (V1, d' 1), (V2, d '2), …, (Vn, d' n).

For example, when the controller 601 outputs a dc voltage V1 to the coil 604 to move the magnetic member 603, the displacement of the magnetic member at this time can be found to be d'1 based on the correspondence between the dc voltage and the magnetic member displacement stored in advance.

When the movement of the magnetic member 603 is stopped, the controller 601 outputs a predetermined ac voltage to the coil 604.

The preset alternating voltage superposition alternating voltage and the direct voltage have the same effective value.

The implementation manner of determining the movement stop of the magnetic component 603 is the same as that described in the above embodiment, and is not described herein again.

During the movement of the magnetic component 603, the magnetic core 605 also moves, and at this time, the relative movement between the coil 604 and the magnetic core 605 may cause the inductance of the coil 604 to change, thereby causing the current at the output end of the coil 604 to change.

At this time, the current at the output end of the coil 604 is obtained, and the inductance of the coil 604 corresponding to the displacement caused by the movement of the magnetic member 603 is obtained by calculation using the equation (2).

The controller 601 obtains the corresponding inductance when the magnetic component 603 generates different displacements by outputting different direct-current voltages, and thus calibration of the corresponding relationship between the inductance and the actual displacement of the magnetic component can be completed.

In some embodiments, the corresponding relationship between the inductance and the actual displacement of the magnetic component may be stored in the form of a data table, which is described above in detail and is not described herein again.

In summary, the method for calibrating the corresponding relationship between the inductance and the actual displacement of the magnetic component provided by the embodiment of the present application can be completed by the detection system for the lens position provided by the above embodiment without additionally adding a structure.

In another possible implementation manner, since the relative positions of the magnetic component and the lens are fixed, after the relative positions of the magnetic component and the lens are determined, the displacement of the magnetic component can be converted into the position of the lens.

Therefore, the data table stored in the above memory may also be a correspondence relationship between the inductance and the lens position.

In order to obtain the corresponding relationship between the inductance and the lens position, in the process of calibrating the corresponding relationship between the inductance and the actual position of the magnetic part, after the corresponding relationship between the inductance and the actual displacement of the magnetic part is obtained, the lens position is obtained according to the actual displacement of the magnetic part, so that the corresponding relationship between the inductance and the lens position is obtained.

Through the implementation mode of storing the corresponding relation between the inductance and the lens position, the lens position can be directly obtained according to the inductance without determining the actual displacement of the magnetic part at first and then determining the lens position through the actual displacement of the magnetic part, so that the processing process can be simplified.

Another implementation of determining the lens position based on the correspondence between current and displacement/position is described below.

The controller 601 outputs a dc voltage to the coil 604, and the magnetic field generated by the coil 604 causes the magnetic member 603 to move.

When it is determined that the magnetic member 603 stops moving, the controller 601 outputs a dc voltage to the coil 604 in which a predetermined ac voltage is superimposed.

The implementation manner of determining that the magnetic component 603 stops moving is the same as that described in the above embodiment, and is not described here again.

Since the coil 604 is fixed and the relative positions of the magnetic component 603 and the magnetic core 605 are fixed, during the movement of the magnetic component 603, there is a relative movement between the coil 604 and the magnetic core 605, which results in a change in the inductance of the coil 604.

At this time, the inductance of the coil 604 changes, and the current at the output end of the coil 604 changes.

The controller 601 obtains the actual displacement of the magnetic component corresponding to the current according to the corresponding relationship between the current and the actual displacement of the magnetic component, which is obtained through test calibration in advance.

In some embodiments, the current may be the magnitude or frequency of the current at the output of the coil 604 in the above correspondence between the current and the actual displacement of the magnetic component, taking into account the change in the inductance of the coil 604, which may result in a change in the magnitude or frequency of the current at the output of the coil 604.

The above correspondence between the current and the actual displacement of the magnetic component may be stored in a memory of the electronic device and recalled when the controller 601 is in use.

In some embodiments, the correspondence between the current and the actual displacement of the magnetic component may be stored in the form of a data table. For example, the actual displacement of the magnetic member is d1 when the current is i1, … when the inductance is i2, and dn when the current is in, and the actual displacement of the magnetic member is dn, the corresponding relationship stored is (i 1, d 1), (i 2, d 2), …, (in, dn) through test calibration.

The actual displacement of the magnetic component obtained through the above process is the displacement actually generated by the magnetic component 603, and the displacement already covers the offset of the magnetic component 603 and the lens due to factors such as gravity; the displacement of the magnetic member corresponding to the dc voltage is ideally a displacement of the coil corresponding to the dc voltage, which can be generated by controlling the voltage value of the dc voltage, that is, the displacement of the magnetic member corresponding to the dc voltage does not take into account the offset caused by gravity and the like.

The controller 601 determines the position of the lens based on the actual displacement of the magnetic member obtained by the above-described process.

Because the relative position of the magnetic part and the lens is not changed, the magnetic part can drive the lens to move when moving. Therefore, by determining the actual displacement of the magnetic member, i.e., the displacement of the lens, the position of the lens can be determined.

In summary, the lens position is determined based on the corresponding relationship between the current and the displacement/position, the current at the output end of the magnetic component can be directly utilized, and the inductance of the coil does not need to be obtained through current calculation, so that the processing process is simplified.

Therefore, the data table stored in the above memory may be a relationship in which the current and the lens position correspond to each other. For example, it is obtained in advance through test calibration that when the current is i1, the lens position is l1, when the current is i2, the lens position is l2, …, and when the current is in, the lens position is ln, the corresponding relationship stored is (i 1, l 1), (i 2, l 2), …, (in, ln).

In the above embodiment, after the current at the output end of the coil is obtained, the actual displacement of the coil is determined according to the correspondence between the current calibrated in advance through the test and the actual displacement of the magnetic component.

The manner of the correspondence between the calibration current and the actual displacement of the magnetic component is described in detail below with reference to the accompanying drawings.

The lens position detection system provided in the above embodiment can be used to implement the following manner of mapping the current to the actual displacement of the magnetic component.

According to the principle that the VCM moves the movable member, there is a correspondence relationship between the dc voltage for driving the coil 604 to generate the magnetic field and the displacement generated by the movement of the magnetic member 603, that is, the correspondence relationship between the dc voltage and the displacement of the magnetic member.

For an electronic device capable of moving a lens by a VCM, the correspondence between the dc voltage and the displacement of the magnetic member is prestored.

In some embodiments, the correspondence between the dc voltage and the displacement of the magnetic component may be stored in the form of a data table. For example, when the dc voltage is V1, the magnetic member displacement is d '1, when the dc voltage is V2, the magnetic member displacement is d'2, …, and when the voltage value of the dc voltage is Vn, the magnetic member displacement is d 'n, and the correspondence relationship stored is (V1, d' 1), (V2, d '2), …, (Vn, d' n).

At this time, the current at the output of the coil 604 is obtained.

The controller 601 outputs different dc voltages to the coil 604 to obtain the current of the coil 604 when the magnetic component generates different displacements, so as to complete the calibration of the corresponding relationship between the current and the actual displacement of the magnetic component.

In some embodiments, the corresponding relationship between the current and the actual displacement of the magnetic component may be stored in the form of a data table, which is described above in detail and is not described herein again.

In summary, the manner of calibrating the corresponding relationship between the current and the actual displacement of the magnetic component provided by the embodiment of the present application can be completed by the system for detecting the lens position provided by the above embodiment, without adding an additional structure.

In the above embodiments, the technical solution provided in the present application is applied to correct the optical axis deviation of the lens in the electronic device, that is, to adjust the position of the lens in the direction perpendicular to the optical axis.

In addition, the technical scheme provided by the application can also be applied to an automatic focusing scene of a lens in electronic equipment, the implementation principle is the same as that in the above embodiment, and only the adjustment directions of the lens are different.

Since the moving-magnet VCM is mostly applied to a scene for correcting lens optical axis deviation, descriptions of technical solutions provided in the present application in a scene of lens auto-focusing are not repeated here.

Referring to fig. 14, fig. 14 is a schematic structural diagram of a voice coil motor according to another embodiment of the present disclosure.

As shown in fig. 14, the voice coil motor 700 includes a magnetic member 701, a coil 702, and a core 703.

The coil 702 surrounds the magnetic core 703, the position of the coil 702 is fixed, the relative positions of the magnetic component 701 and the magnetic core 703 are fixed, and the magnetic component 701 is used for generating movement corresponding to external driving voltage when the coil is externally connected with the driving voltage.

Compared with a moving-magnet VCM, which is commonly used in electronic devices at present, in the voice coil motor provided in the embodiment of the present application, one magnetic core 703 is nested in a coil.

Referring to the above description of the VCM principle in the embodiment, when the driving voltage of the control coil 702 is a dc voltage, the magnetic member 701 and the coil 702 are relatively moved.

Since the relative positions of magnetic component 701 and magnetic core 703 are fixed, magnetic core 703 and coil 702 move relatively at this time.

When the vcm 700 is used to move a movable component, such as a lens, the relative position between the magnetic component 701 and the lens is fixed, and the movement of the magnetic component 701 can move the lens to adjust the position of the lens.

When it is determined that the magnetic member 701 reaches the first position, that is, when it is determined that the magnetic member 701 stops moving, the driving voltage of the control coil 702 is an alternating voltage having the same effective value as the above-described direct voltage.

At this time, the inductance of the coil 702 changes due to the relative movement of the coil 702 and the core 703, and the displacement of the magnetic member 701 and hence the position of the lens can be determined by the current at the output end of the coil 702.

The specific principle of the foregoing implementation has been described in the foregoing embodiments, and the description of the present embodiment is omitted here.

In one possible implementation, the magnetic component may be located inside the coil, i.e. the coil surrounds the outside of the magnetic component, enabling a reduction in the size of the VCM.

The detection module comprises a magnetic component, a coil and a magnetic core, wherein the coil is wound outside the magnetic core, the position of the coil is fixed, and the relative position of the magnetic component and the magnetic core is fixed.

Referring to fig. 15, fig. 15 is a flowchart of a method for detecting a lens position according to another embodiment of the present application.

The detection method includes S801-S803.

S801, controlling the driving voltage of the control coil to be a first voltage so as to enable the magnetic component and the coil to move relatively, wherein the first voltage is a direct-current voltage;

s802, when the magnetic component is determined to reach the first position, controlling the driving voltage of the coil to be a second voltage, wherein the second voltage is an alternating current voltage, and the effective values of the first voltage and the second voltage are the same;

and S803, determining the position of the lens by using the current of the output end of the coil.

When the driving voltage of the control coil is a first voltage and the first voltage is a direct current voltage, the magnetic member and the coil relatively move.

Since the relative positions of the magnetic member and the core are fixed, the core and the coil are relatively moved.

Because the relative position of magnetic part and camera lens is fixed, the removal of magnetic part can drive the camera lens and move.

When the magnetic component is determined to reach the first position, namely the magnetic component is determined to stop moving, the driving voltage of the control coil is a second voltage, the second voltage is an alternating current voltage, and effective values of the first voltage and the second voltage are the same.

Since the effective values of the first voltage and the second voltage are the same, when the magnetic member reaches the first position, that is, the magnetic member stops moving, the driving voltage of the control coil becomes the second voltage, and the magnetic member does not continue to move.

Since the current at the output of the coil is related to the inductance of the coil, i.e. to the displacement of the magnetic component relative to the movement of the coil; since the relative positions of the magnetic member and the lens are fixed, the position of the lens can be determined based on the current at the output end of the coil.

The embodiment of the present application further provides another method for detecting a lens position, which is applied to the detection module in the above embodiment, that is, the detection module in the embodiment corresponding to fig. 13.

Referring to fig. 16, fig. 16 is a flowchart of a method for detecting a lens position according to another embodiment of the present application.

The detection method includes S901-S906.

And S901, outputting direct current voltage to the coil so as to enable the magnetic component and the coil to move relatively.

The principle of the relative movement between the magnetic component and the coil is described in the above embodiments, and is not described herein again.

And S902, when the magnetic component is determined to stop moving, superposing a preset alternating voltage on the direct current voltage and outputting the superposed alternating voltage to the coil.

For the implementation manner of determining the movement stop of the magnetic component in S902, which has been described in the above embodiments, the embodiments of the present application are not described herein again.

And S903, detecting the current of the output end of the coil.

In S903, since there is relative movement between the coil and the core during movement of the magnetic member, the inductance of the coil changes. When an alternating voltage is applied to the coil, the current at the output of the coil changes.

And S904, calculating the inductance of the coil according to the detected current.

In some embodiments, the manner of calculating the inductance of the coil from the current may be implemented according to equation (2). The specific implementation manner is described in the above embodiments, and the embodiments of the present application are not described herein again.

And S905, obtaining the actual displacement of the magnetic component according to the corresponding relation between the inductance calibrated in advance and the actual displacement of the magnetic component.

In some embodiments, the corresponding relationship between the actual displacement of the inductor and the actual displacement of the magnetic component may be stored in the form of a data table, and the specific manner is described in the foregoing embodiments, and is not described herein again.

And S906, determining the position of the lens according to the actual displacement of the magnetic component.

Since the positions of the magnetic component and the lens are fixed, after the inductance of the coil is obtained in S904, the corresponding relationship according to which the lens position is determined may also be the corresponding relationship between the inductance and the lens position.

In another possible implementation manner, after the inductance of the coil is obtained in S904, the position of the lens is obtained according to a correspondence relationship between the inductance and the lens position that are calibrated in advance.

The corresponding relation between the inductance and the lens position is calibrated in advance, the lens position can be directly obtained according to the inductance without determining the actual displacement of the magnetic part at first and then determining the lens position through the actual displacement of the magnetic part, and therefore the processing process can be simplified.

In the above embodiment, the determination that the magnetic member movement is stopped is the trigger condition for superimposing the ac voltage output on the dc voltage. In order to determine that the magnetic component stops moving, that is, the magnetic component reaches the first position, the following two implementations are provided in the embodiments of the present application, please refer to fig. 17 and 18.

Referring to fig. 17, fig. 17 is a flowchart of a method for detecting a lens position according to another embodiment of the present application, where the method is applied to a detection module in the embodiment corresponding to fig. 13.

The method includes S1001-S1006.

And S1001, outputting direct current voltage to the coil so as to enable the magnetic component and the coil to move relatively.

And S1002, after the direct-current voltage is output for a preset time period, superposing a preset alternating-current voltage on the direct-current voltage for outputting, wherein the preset time period is obtained according to a preset time period calibrated in advance and the corresponding relation of the direct-current voltage.

In S1002, a preset ac voltage output is superimposed on the dc voltage, and the effective value of the voltage is maintained.

The preset time period corresponds to the direct-current voltage and is determined according to the corresponding relation between the preset time period and the direct-current voltage which are calibrated in advance. The correspondence relationship indicates that the magnetic member moves when the voltage across the coil is the dc voltage, and the magnetic member stops moving within a preset time period corresponding to the dc voltage.

S1003, detecting the current of the output end of the coil.

And S1004, calculating the inductance of the coil according to the detected current.

And S1005, obtaining the actual displacement of the magnetic component according to the corresponding relation between the inductance calibrated in advance and the actual displacement of the magnetic component.

And S1006, determining the position of the lens according to the actual displacement of the magnetic component.

And determining the preset time period corresponding to the current direct current voltage according to the corresponding relation between the preset time period and the direct current voltage calibrated in advance, and determining that the magnetic component stops moving after the direct current voltage lasts for the preset time period.

Since the positions of the magnetic member and the lens are fixed, after the inductance of the coil is obtained in S1004, the correspondence relationship according to which the lens position is determined may also be the correspondence relationship between the inductance and the lens position.

In another possible implementation manner, after the inductance of the coil is obtained in S1004, the position of the lens is obtained according to a pre-calibrated correspondence between the inductance and the lens position.

The corresponding relation between the inductance and the lens position is calibrated in advance, the lens position can be directly obtained according to the inductance, the actual displacement of the magnetic part does not need to be determined at first, and then the lens position is determined through the actual displacement of the magnetic part, so that the processing process can be simplified.

Referring to fig. 18, fig. 18 is a flowchart of a lens position detecting method according to another embodiment of the present application, the method is applied to the detection module in the embodiment corresponding to fig. 13.

The method includes S1101-S1106.

S1101, outputting direct current voltage to the coil so that the magnetic component and the coil move relatively.

And S1102, detecting the current of the output end of the coil.

And S1103, superposing a preset alternating voltage on the direct current voltage for outputting when the current at the output end of the coil is not changed.

When the voltage across the coil is a constant dc voltage, the current of the coil is typically a constant dc current.

However, when a magnetic field is generated around the energized coil, the magnetic member moves in the magnetic field. Because the position of the coil is fixed, relative motion is generated between the coil and the magnetic component, so that the electrified coil cuts magnetic induction lines in a magnetic field generated by the magnetic component, and electromotive force is generated when the coil cuts the magnetic induction lines.

Therefore, during the movement of the magnetic member, the coil cuts the electromotive force generated by the magnetic induction wire, so that the current passing through the coil is not constant.

When the magnetic member stops moving, the electromotive force generated by the coil cutting the magnetic induction wire disappears, and therefore, the current of the coil becomes constant.

Therefore, when the current at the output end of the coil is constant, it can be determined that the magnetic member stops moving.

And S1104, calculating the inductance of the coil according to the detected current.

S1105, obtaining the actual displacement of the magnetic component according to the corresponding relation between the inductance calibrated in advance and the actual displacement of the magnetic component.

And S1106, determining the position of the lens according to the actual displacement of the magnetic component.

Unexpected motion may occur due to the magnetic components being affected by other factors during movement. For example, during the movement of the magnetic member, the direct-current voltage applied to both ends of the coil is accidentally fluctuated, so that the magnetic member is irregularly moved. In this case, the above-described manner of determining the stop of the movement of the magnetic member can reduce the occurrence of erroneous results due to accidental occurrences.

Since the positions of the magnetic component and the lens are fixed, after the inductance of the coil is obtained in S1105, the corresponding relationship according to which the lens position is determined may also be the corresponding relationship between the inductance and the lens position.

In another possible implementation manner, after the inductance of the coil is obtained in S1105, the position of the lens is obtained according to the corresponding relationship between the inductance and the lens position calibrated in advance. The corresponding relation between the inductance and the lens position is calibrated in advance, the lens position can be directly obtained according to the inductance without determining the actual displacement of the magnetic part at first and then determining the lens position through the actual displacement of the magnetic part, and therefore the processing process can be simplified.

Further, in order to obtain the corresponding relationship between the actual displacement of the inductor and the actual displacement of the magnetic component in S1105, an embodiment of the present application further provides a calibration method for the corresponding relationship between the actual displacement of the inductor and the actual displacement of the magnetic component, and the method is applied to the detection module in the embodiment corresponding to fig. 13.

First, a DC voltage is output to the coil to move the magnetic member and the coil relatively.

When the magnetic component is determined to stop moving, superposing a preset alternating voltage on the direct current voltage for outputting; and superposing a preset alternating voltage on the direct current voltage for outputting, wherein the effective value of the voltage is kept unchanged.

Then, the current at the output end of the coil is detected, and the inductance of the coil is calculated according to the detected current.

And after the inductance of the coil is obtained, obtaining the corresponding relation between the inductance and the actual displacement of the magnetic part based on the corresponding relation between the pre-calibrated direct-current voltage and the displacement of the magnetic part according to the inductance of the coil.

According to the principle that the VCM moves the lens, there is a corresponding relationship between the dc voltage at the two ends of the coil and the displacement generated by the movement of the magnetic component, that is, the corresponding relationship between the dc voltage and the displacement of the magnetic component.

And outputting a preset alternating voltage to the coil after the magnetic component stops moving.

During the movement of the magnetic component, the relative movement between the coil and the core causes a change in the inductance of the coil, and thus a change in the current at the output of the coil.

At this time, the current at the output end of the coil is obtained, and the inductance of the coil can be obtained by calculating according to the formula (2).

By outputting different direct current voltages, the corresponding inductance when the magnetic component generates different displacements is obtained, and the calibration of the corresponding relation between the inductance and the actual displacement of the magnetic component can be completed.

In summary, the calibration method for the correspondence between the inductance and the actual displacement of the magnetic component provided in the embodiment of the present application can be applied to the detection module in the detection system for the lens position provided in the above embodiment, without additionally adding a structure for completing the calibration process.

In a possible implementation manner, since the relative positions of the magnetic component and the lens are fixed, the corresponding relationship between the inductance and the lens position can also be calibrated.

In order to calibrate the corresponding relationship between the inductance and the lens position, the inductance of the coil can be obtained by calculating according to the formula (2) according to the obtained current of the output end of the coil. The direct current voltage at the two ends of the coil is controlled to control the magnetic part to drive the lens to move, so that different lens positions are obtained, and the calibration of the corresponding relation between the inductance and the lens positions can be completed.

The embodiment of the application also provides another method for detecting the position of the lens, and the method determines the position of the lens based on the corresponding relation between the current and the actual displacement of the magnetic component. The method is used for directly utilizing the current at the output end of the coil without calculating the inductance of the coil through the current, thereby simplifying the processing process.

Referring to fig. 19, fig. 19 is a flowchart of a method for detecting a lens position according to another embodiment of the present application, where the method is applied to a detection module in the embodiment corresponding to fig. 13.

The method includes S1201-S1204.

S1201, a dc voltage is output to the coil to move the magnetic member and the coil relative to each other.

And S1202, superposing a preset alternating current voltage on the direct current voltage for outputting after the magnetic component is determined to stop moving.

And S1203, detecting the current of the output end of the coil.

And S1204, obtaining the lens position according to the detected current and the corresponding relation between the pre-calibrated current and the lens position.

It is to be understood that the method of determining the lens position based on the correspondence between the current and the actual displacement of the magnetic member is similar to the method of determining the lens position based on the correspondence between the inductance and the actual displacement of the magnetic member in the above-described embodiment.

Since the positions of the magnetic component and the lens are fixed, in another possible implementation manner, after the current of the output end of the coil is obtained in S1203, the corresponding relationship according to which the position of the lens is determined may also be a process of obtaining the actual displacement of the magnetic component according to the current of the output end of the coil, and then determining the position of the lens according to the actual displacement of the magnetic component.

Further, in order to obtain the corresponding relationship between the current and the lens position in S1104, an embodiment of the present application further provides a calibration method for the corresponding relationship between the current and the lens position, and the method is applied to the detection module in the embodiment corresponding to fig. 13.

First, a dc voltage is output to the coil to move the magnetic member and the coil relative to each other.

When the magnetic component is determined to stop moving, the preset alternating voltage output is superposed on the direct current voltage, and the effective value of the voltage is kept unchanged.

And detecting the current at the output end of the coil, and then obtaining the corresponding relation between the current and the lens position based on the corresponding relation between the pre-calibrated direct-current voltage and the displacement of the magnetic component according to the current at the output end of the coil.

And when the magnetic component stops moving, outputting alternating voltage superposed with the alternating voltage to the coil.

The controller obtains corresponding currents when the magnetic component generates different displacements by outputting different direct-current voltages, and calibration of the corresponding relation between the currents and the actual displacement of the magnetic component can be completed.

In a possible implementation manner, since the relative position of the magnetic component and the lens is fixed, the corresponding relationship between the inductance and the actual displacement of the magnetic component can also be calibrated.

Based on the detection system provided by the above embodiment, an embodiment of the present application further provides an electronic device using the detection system, which is specifically described below with reference to the accompanying drawings.

The hardware structure of the electronic device provided in the embodiment of the present application is as shown in fig. 1A, and the lens module of the electronic device provided in the embodiment of the present application includes the detection system in the embodiment of the detection system for the lens position.

Referring to fig. 20, fig. 20 is a schematic structural diagram of an electronic device according to another embodiment of the present application, where the electronic device 800 includes a detection system 801 and a lens 802 in the above embodiment of a lens position detection system, where the detection system 801 specifically includes a controller 803 and a detection module 804.

The detection system 801 refers to the above embodiments of the lens position detection system, and is configured to implement the functions described in the above embodiments of the lens position detection system.

In order to realize the automatic focusing function of the lens of the electronic equipment, the electronic equipment can comprise a detection system for determining the position of the lens along the optical axis direction; in order to realize the function of correcting the optical axis deviation of the lens, the electronic device may include two detection systems, which are respectively used for determining the position of the lens perpendicular to the optical axis direction;

in order to implement the above two functions, i.e., the auto-focusing function of the lens and the correction function of the optical axis deviation of the lens, the electronic device may include three detection systems for determining the position of the lens along the optical axis direction and the direction perpendicular to the optical axis direction, respectively.

The detection system provided by the embodiment of the application can have different structures and realize corresponding functions. When the electronic device 800 includes a plurality of detection devices, the plurality of detection devices may have the same structure or different structures, which is not limited in this embodiment of the present application.

When the electronic device 800 includes a plurality of the above detection systems, the controllers in the plurality of detection systems may be the same controller to implement the corresponding functions, that is, the same controller controls the detection modules in the plurality of detection systems to implement the functions of the plurality of detection systems; each detection system may also correspond to a respective controller, which is not limited in this embodiment of the present application.

When the electronic device 800 includes a plurality of the above-mentioned detecting systems, the detecting modules for detecting the lens positions along the optical axis and perpendicular to the optical axis can be controlled by the same controller, and the detecting modules for detecting the lens positions perpendicular to the optical axis can be controlled by another controller.

The embodiment of the present application does not specifically limit the type of the electronic device, and the electronic device may be a mobile phone, a notebook computer, a wearable electronic device (e.g., a smart watch), a tablet computer, an Augmented Reality (AR) device, a Virtual Reality (VR) device, or the like.

It can be understood that, in this embodiment, a specific implementation manner of the detection system in the electronic device and functions that can be implemented by the detection system are already described in the above embodiments, and details of the embodiments of the present application are not described herein again.

In summary, with the detection systems provided in the above embodiments, the number and/or types of the detection systems included in the electronic device are selected according to the functional requirements of the electronic device, such as the requirement for implementing the auto-focus function of the lens and/or the correction function of the optical axis deviation.

Since the electronic device usually includes a VCM for the function of adjusting the lens position.

According to the electronic equipment provided by the embodiment of the application, in order to realize automatic focusing of the lens or deviation correction of the optical axis of the lens, the magnetic core is additionally arranged in the VCM, and the magnetic core is embedded in the hollow position of the coil, so that the detection of the position of the lens is realized.

Compared with a mode of realizing lens position feedback by adding a Hall element, in the electronic equipment provided by the embodiment of the application, the size of the device is not excessively increased in the optical axis direction along the lens and the optical axis direction perpendicular to the lens, so that the structural limitation on the camera module is reduced.

In addition, compared with a Hall element, the magnetic core is low in cost, and therefore the electronic equipment provided by the embodiment of the application can reduce the cost of a device for detecting the position of the lens.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. The above-described apparatus embodiments are merely illustrative, and the units and modules described as separate components may or may not be physically separate.

In addition, some or all of the units and modules may be selected according to actual needs to achieve the purpose of the solution of the embodiment. One of ordinary skill in the art can understand and implement without inventive effort.

The foregoing is directed to embodiments of the present application and it is noted that numerous modifications and adaptations may be made by those skilled in the art without departing from the principles of the present application and are intended to be within the scope of the present application.

Claims

1. A lens position detection system, the detection system comprising: the detection module and the controller;

the detection module comprises a first magnet, a second magnet, a coil and a magnetic core;

the coil is positioned in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and the lens is fixed, the coil surrounds the magnetic core, and the position of the magnetic core is fixed;

the controller is used for controlling the driving voltage of the coil to be a first voltage so that the coil and the magnetic core move relatively, when the coil is determined to reach the first position, the driving voltage of the coil is controlled to be a second voltage, the position of the lens is determined by utilizing the current of the output end of the coil, the first voltage is a direct current voltage, the second voltage is an alternating current voltage, and the effective values of the first voltage and the second voltage are the same.

2. The system of claim 1, wherein the controller is specifically configured to superimpose the first voltage with a preset ac voltage to obtain the second voltage.

3. The system according to claim 1 or 2, wherein the controller is configured to determine the displacement of the coil by using a current at an output of the coil, and to determine the position of the lens according to the relative position of the coil and the lens.

4. The system for detecting the position of the lens according to claim 3, wherein the controller is specifically configured to determine the inductance of the coil according to the current at the output end of the coil and the preset ac voltage, and determine the displacement of the coil according to a pre-calibrated correspondence between the inductance and the displacement of the coil.

5. The system for detecting the position of the lens according to claim 3, wherein the controller is specifically configured to determine the displacement of the coil according to a pre-calibrated correspondence between the current and the displacement of the coil and the current at the output end of the coil.

6. The system for detecting the position of the lens according to claim 2, wherein the controller is specifically configured to determine the inductance of the coil by using the current at the output end of the coil and the preset ac voltage, and determine the position of the lens according to a pre-calibrated correspondence between the inductance and the position of the lens.

7. The system for detecting a lens position according to claim 2, wherein the controller is specifically configured to determine the position of the lens by using a pre-calibrated correspondence between the current and the lens position and the current at the output end of the coil.

8. The system for detecting a lens position according to claim 1, wherein the controller is specifically configured to determine that the coil reaches the first position after controlling the driving voltage of the coil to be the first voltage for a preset time period.

9. The system for detecting a lens position according to claim 1, wherein the controller is configured to determine that the coil reaches the first position when a current at an output of the coil is constant.

10. The system for detecting the position of a lens according to any one of claims 1 to 9, wherein the magnetic core has a hollow structure.

11. A lens position detection system, the detection system comprising: the detection module and the controller;

the detection module comprises a magnetic component, a coil and a magnetic core;

the coil is wound outside the magnetic core, and the position of the coil is fixed;

the relative positions of the magnetic component and the magnetic core are fixed;

the controller is used for controlling the driving voltage of the coil to be a first voltage so as to enable the magnetic component and the coil to move relatively, when the magnetic component is determined to reach the first position, the driving voltage of the coil is controlled to be a second voltage, the position of the lens is determined by utilizing the current of the output end of the coil, the first voltage is a direct current voltage, the second voltage is an alternating current voltage, and the effective values of the first voltage and the second voltage are the same.

12. The system for detecting a position of a lens according to claim 11, wherein the controller is specifically configured to superimpose the first voltage on a preset ac voltage to obtain the second voltage.

13. The system for detecting the position of a lens according to claim 11 or 12, wherein the controller is configured to determine the displacement of the magnetic member by using the current at the output end of the coil, and determine the position of the lens according to the relative positions of the magnetic member and the lens.

14. The system for detecting the position of a lens according to claim 13, wherein the controller is specifically configured to determine the inductance of the coil according to the current at the output end of the coil and the preset ac voltage, and determine the displacement of the magnetic component according to a pre-calibrated correspondence between the inductance and the displacement of the magnetic component.

15. The system for detecting the position of a lens according to claim 13, wherein the controller is specifically configured to determine the displacement of the magnetic element according to a pre-calibrated correspondence between the current and the displacement of the magnetic element and the current at the output end of the coil.

16. The system for detecting the position of the lens according to claim 12, wherein the controller is specifically configured to determine the inductance of the coil by using the current at the output end of the coil and the preset ac voltage, and determine the position of the lens according to a pre-calibrated correspondence between the inductance and the lens position.

17. The system for detecting the position of a lens according to claim 12, wherein the controller is specifically configured to determine the position of the lens by using a pre-calibrated correspondence between the current and the lens position and the current at the output end of the coil.

18. The system of claim 11, wherein the controller is configured to determine that the magnetic member reaches the first position after controlling the driving voltage of the coil to be the first voltage for a preset time period.

19. The lens position detecting system according to claim 11, wherein the controller is configured to determine that the magnetic member reaches the first position when the current at the output of the coil is constant.

20. The system of any one of claims 11 to 19, wherein the coil surrounds the exterior of the magnetic component.

21. A voice coil motor, comprising: a first magnet, a second magnet, a coil, and a magnetic core;

the coil is positioned in a magnetic field formed by the first magnet and the second magnet, the coil surrounds the magnetic core, and the position of the magnetic core is fixed;

22. A voice coil motor, comprising: a magnetic member, a coil, and a magnetic core;

the coil is wound on the outer part of the magnetic core, and the position of the coil is fixed;

the magnetic component is used for generating movement corresponding to external driving voltage when the coil is externally connected with the driving voltage.

23. The method for detecting the position of the lens is characterized by being applied to a side detection module, wherein the detection module comprises a first magnet, a second magnet, a coil and a magnetic core; the coil is located in a magnetic field formed by the first magnet and the second magnet, the relative position of the coil and the lens is fixed, the coil surrounds the outer portion of the magnetic core, and the position of the magnetic core is fixed, and the method comprises the following steps:

controlling the driving voltage of the coil to be a first voltage so as to enable the coil and the magnetic core to move relatively, wherein the first voltage is a direct current voltage;

when the coil is determined to reach the first position, controlling the driving voltage of the coil to be a second voltage, wherein the second voltage is an alternating voltage, and the effective values of the first voltage and the second voltage are the same;

and determining the position of the lens by using the current of the output end of the coil.

24. The method for detecting the lens position according to claim 23, wherein the controlling the driving voltage of the coil to be a second voltage specifically comprises:

and superposing the first voltage and a preset alternating current voltage to obtain the second voltage.

25. The method for detecting the position of the lens according to claim 23 or 24, wherein the determining the position of the lens by using the current at the output end of the coil specifically comprises:

determining the displacement of the coil by using the current of the output end of the coil;

and determining the position of the lens according to the relative positions of the coil and the lens.

26. The method for detecting the lens position according to claim 25, wherein the determining the displacement of the coil by using the current at the output end of the coil specifically comprises:

determining the inductance of the coil according to the current of the output end of the coil and the preset alternating voltage;

and determining the displacement of the coil according to the corresponding relation between the inductance and the coil displacement which are calibrated in advance.

27. The method for detecting the lens position according to claim 25, wherein the determining the displacement of the coil by using the current at the output end of the coil specifically comprises:

28. The method for detecting the position of the lens according to claim 24, wherein the determining the position of the lens by using the current at the output end of the coil specifically comprises:

determining the inductance of the coil by using the current of the output end of the coil and the preset alternating voltage;

and determining the position of the lens according to the corresponding relation between the pre-calibrated inductance and the position of the lens.

29. The method for detecting the position of the lens according to claim 24, wherein the determining the position of the lens by using the current at the output end of the coil specifically comprises:

30. The method for detecting the position of the lens is characterized by being applied to a side detection module, wherein the detection module comprises a magnetic component, a coil and a magnetic core; the coil is wound outside the magnetic core, and the position of the coil is fixed; the relative positions of the magnetic component and the magnetic core are fixed, the method comprising:

controlling the driving voltage of the coil to be a first voltage so as to enable the magnetic component and the coil to move relatively, wherein the first voltage is a direct current voltage;

when the magnetic component is determined to reach the first position, controlling the driving voltage of the coil to be a second voltage, wherein the second voltage is an alternating current voltage, and the effective values of the first voltage and the second voltage are the same;

31. The method for detecting the lens position according to claim 30, wherein the controlling the driving voltage of the coil to be a second voltage specifically comprises:

32. The method for detecting the position of the lens according to claim 30 or 31, wherein the determining the position of the lens by using the current at the output end of the coil specifically comprises:

determining the displacement of the magnetic component by using the current at the output end of the coil;

and determining the position of the lens according to the relative positions of the magnetic component and the lens.

33. The method for detecting the lens position according to claim 32, wherein the determining the displacement of the magnetic member by using the current at the output end of the coil specifically comprises:

and determining the displacement of the magnetic component according to the corresponding relation between the inductance and the displacement of the magnetic component which are calibrated in advance.

34. The method for detecting the position of the lens according to claim 32, wherein the determining the displacement of the magnetic component by using the current at the output end of the coil specifically comprises:

35. The method for detecting the position of the lens according to claim 31, wherein the determining the position of the lens by using the current at the output end of the coil specifically comprises:

36. The method for detecting the position of the lens according to claim 31, wherein the determining the position of the lens by using the current at the output end of the coil specifically comprises:

and determining the position of the lens by using the corresponding relation between the pre-calibrated current and the lens position and the current of the output end of the coil.

37. An electronic device characterized in that the electronic device comprises the lens position detection system of any one of claims 1 to 20, and further comprises a lens.