Voice coil motor control method and system, storage medium and camera lens

Abstract

The invention relates to the technical field of motors, and discloses a voice coil motor control method and system, a storage medium and a camera lens, and the method comprises the steps: obtaining a first initial value of a first detection signal at an initial moment, and determining an initial relative position between a coil and a magnetic part; in response to the position adjusting signal, determining a target moving position and a preset displacement amount of the coil relative to the magnetic part according to the position adjusting signal; controlling the coil to move relative to the magnetic part, and calculating and acquiring a real-time phase value of the coil in a current cycle period of a second detection signal according to the second detection signal at the current moment; the whole position cycle number of the second detection signal at the current moment is obtained, and the actual displacement of the coil relative to the magnetic part is calculated and obtained; and controlling the coil to move towards the target moving position based on a preset closed-loop control algorithm until the difference value between the preset displacement amount and the actual displacement amount is smaller than a preset displacement error threshold value.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular, to a voice coil motor control method, a voice coil motor control system, a computer-readable storage medium, and a camera lens. Background Art

[0002] A camera lens is usually composed of multiple lenses arranged coaxially in sequence. By adjusting the spacing between two adjacent lenses, the imaging focus of the camera lens can be adjusted. For a camera lens with an autofocus function, a motor is installed inside the camera lens. The motor receives a position adjustment signal to drive the lens to move, so as to adjust the spacing between two adjacent lenses, thereby achieving the technical effect of autofocus of the camera lens.

[0003] In the related art, a voice coil motor can be used as a power source when the lens of an existing camera lens moves. Each time the camera is powered on, power is supplied to the camera lens. After being powered on, the voice coil motor needs to first drive the lens to move to an initial calibration position, and then the initial position is sensed by a sensor. The camera lens can be used normally only after zero calibration. When the above control method is used to control the voice coil motor, the initialization time of the camera lens is too long, and the customer needs to wait for a long time before using the camera to take pictures, which affects the use experience of the camera lens and reduces the product quality of the camera lens. Summary of the Invention

[0004] The purpose of the present application is to reduce the initialization time of the camera lens, enable the customer to use the camera to take pictures faster after the camera is powered on, thereby improving the use experience of the camera lens, and further improving the product quality of the camera lens.

[0005] To achieve the above purpose, the present application provides a voice coil motor control method.

[0006] The present application further provides a voice coil motor control system.

[0007] The present application further provides a computer-readable storage medium.

[0008] The present application further provides a camera lens.

[0009] According to the voice coil motor control method of the present application, the voice coil motor includes a magnetic member and a coil. Along a first direction, the magnetic member has opposite first and second ends, and the coil is adapted to move relative to the magnetic member along the first direction. The voice coil motor control method includes:

[0010] Obtaining a first initial value of a first detection signal at an initial moment, and determining an initial relative position between the coil and the magnetic member according to the first initial value;

[0011] In response to a position adjustment signal, determine a target movement position and a preset displacement amount of the coil relative to the magnetic member according to the position adjustment signal;

[0012] Control the movement of the coil relative to the magnetic member, obtain a plurality of second detection signals at the current moment, and calculate and obtain a real-time phase value of the coil within the current cycle period of the second detection signals according to the plurality of second detection signals at the current moment;

[0013] Obtain the integer position cycle number of the second detection signal at the current moment, and calculate and obtain the actual displacement amount of the coil relative to the magnetic member according to the integer position cycle number at the current moment, the unit displacement amount of the coil within each cycle period of the second detection signal, and the real-time phase value;

[0014] Based on the preset displacement amount and the actual displacement amount, control the coil to move towards the target movement position based on a preset closed-loop control algorithm. When the difference between the preset displacement amount and the actual displacement amount is less than a preset displacement error threshold, control the coil to stop moving;

[0015] Wherein, in the direction from the first end to the second end, the value of the first detection signal changes monotonically and continuously, the value of each second detection signal changes periodically and continuously, and there is a preset phase difference between any two adjacent second detection signals.

[0016] According to the voice coil motor control method of the present application, by obtaining the first detection signal and the second detection signal, using the first initial value of the first detection signal to determine the initial relative position between the coil and the magnetic member, and using the second detection signal to control the coil to accurately move towards the target movement position relative to the magnetic member. Compared with the prior art, the voice coil motor of the present application does not need to perform zero calibration during initialization, which can reduce the initialization time of the voice coil motor, reduce the waiting time after the camera lens equipped with the voice coil motor is powered on, thereby improving the use experience of the camera lens, and further improving the product quality of the camera lens.

[0017] In some examples of the present application, before the response to the position adjustment signal, it further includes: determining an initial rough position range of the coil according to the first detection signal; obtaining second initial values of a plurality of the second detection signals at the initial moment, and determining an initial accurate position range of the coil according to the plurality of second initial values, wherein each rough position range of the coil corresponds to a plurality of accurate position ranges.

[0018] In some examples of the present application, the voice coil motor includes a first detection member and an induction magnet. The induction magnet is arranged to extend along the first direction. The first detection member is arranged opposite to the induction magnet. The first detection member is used to detect the magnetic induction intensity on one side corresponding to the induction magnet and generate the first detection signal. On the side of the induction magnet opposite to the first detection member, the polarity of the induction magnet close to the first end is opposite to the polarity close to the second end, and in the direction from the first end to the second end, the magnetic induction intensity of the induction magnet changes monotonically. Or, on the side of the induction magnet opposite to the first detection member, the polarity of the induction magnet close to the first end is the same as the polarity close to the second end, and in the direction from the first end to the second end, the magnetic induction intensity of the induction magnet changes monotonically.

[0019] In some examples of the present application, the second detection signal includes a first detection sub-signal and a second detection sub-signal. The voice coil motor includes a second detection member and a third detection member. When the coil moves relative to the magnetic member, the second detection member generates the first detection sub-signal corresponding to the displacement amount of the coil, and the third detection member generates the second detection sub-signal corresponding to the displacement amount of the coil. The second detection member and the third detection member are arranged at intervals along the first direction. The unit displacement amount of the coil in each cycle period of the second detection signal is P, the interval distance between the second detection member and the third detection member is z1, and the preset phase difference between the first detection sub-signal and the second detection sub-signal is A. P, z1, and A satisfy the relationship: A = 2πz1 / P. The output value Va of the first detection sub-signal and the output value Vb of the second detection sub-signal satisfy the relationship: Va = K*sin(2πz / P); Vb = K*sin(2πz / P + A), where K is the preset signal amplitude.

[0020] In some examples of the present application, calculating and obtaining the real-time phase value of the coil in the current cycle period of the second detection signal according to multiple second detection signals at the current moment includes: calculating and obtaining the amplitude Va of the first detection sub-signal in the current cycle period according to the first real-time output value of the first detection sub-signal at the current moment, and calculating and obtaining the amplitude Vb of the second detection sub-signal in the current cycle period according to the second real-time output value of the second detection sub-signal at the current moment; calculating and obtaining the real-time phase value of the coil in the current cycle period of the second detection signal according to the amplitude Va of the first detection sub-signal in the current cycle period and the amplitude Vb of the second detection sub-signal in the current cycle period.

[0021] In some examples of the present application, the integer position cycle number of the second detection signal at the current moment is N tThe obtaining of the integer position cycle number of the second detection signal at the current moment includes: obtaining the integer position cycle number N of the second detection signal at the previous moment t-1 and the real-time phase value θ t-1 ; determining whether θ t and θ t-1 satisfy the relational expression: θ t > θ t-1 , and 0 ≤ θ t-1 < π / 2, and 3π / 2 < θ t ≤ 2π. If satisfied, N t and N t-1 satisfy the relational expression: N t = N t-1 - 1; if not satisfied, then determine whether θ t and θ t-1 satisfy the relational expression: θ t < θ t-1 , and 3π / 2 < θ t-1 ≤ 2π, and 0 ≤ θ t < π / 2. If satisfied, N t and N t-1 satisfy the relational expression: N t = N t-1 + 1; if not satisfied, then N t and N t-1 satisfy the relational expression: N t = N t-1 ; where, at any two adjacent detection moments of the second detection signal, θ t-1 and θ t satisfy the relational expression: 0 ≤ |θ t - θ t-1 | ≤ π / 2.

[0022] In some examples of the present application, the voice coil motor further includes a magnetic grating, the magnetic grating has a plurality of magnetic pole units arranged in sequence along the first direction, the second detection member and the third detection member are both disposed opposite to the same side wall of the magnetic grating, the second detection member is used to detect the magnetic induction intensity on the corresponding side of the magnetic grating and generate the first detection sub-signal, and the third detection member is used to detect the magnetic induction intensity on the corresponding side of the magnetic grating and generate the second detection sub-signal; on the side of the magnetic grating opposite to the second detection member and the third detection member, the polarities of any two adjacent magnetic pole units are opposite, the length dimension of each magnetic pole unit along the first direction is the same, and the magnitude of the magnetic induction intensity of each magnetic pole unit is the same.

[0023] The voice coil motor control system according to the present application is applicable to the above-mentioned voice coil motor control method. The voice coil motor control system includes: a detection module for detecting and obtaining a first detection signal and a second detection signal in real time; a signal receiving module for receiving a position adjustment signal; a power supply module for supplying power to or cutting off power from the coil to control the movement of the coil relative to the magnetic member; a cycle accumulation module for accumulating and calculating the number of full position cycles of the second detection signal when the coil moves towards the target moving position; a calculation module for determining the initial relative position between the coil and the magnetic member according to the first initial value of the first detection signal at the initial moment, and further for determining the target moving position and the preset displacement amount of the coil relative to the magnetic member according to the position adjustment signal, and further for calculating and obtaining the real-time phase value of the coil within the current cycle period of the second detection signal according to the second detection signal at the current moment, and further for calculating and obtaining the actual displacement amount of the coil relative to the magnetic member according to the number of full position cycles of the second detection signal at the current moment, the unit displacement amount of the coil within each cycle period of the second detection signal, and the real-time phase value; a judgment module for judging whether the difference between the preset displacement amount and the actual displacement amount is less than a preset displacement error threshold.

[0024] The voice coil motor control system according to the present application obtains a first detection signal and a second detection signal through the detection module. The calculation module determines the initial relative position between the coil and the magnetic member by using the first initial value of the first detection signal, and controls the coil to move accurately towards the target moving position relative to the magnetic member by using the second detection signal. Compared with the prior art, the voice coil motor of the present application does not need to perform zero calibration during initialization, which can reduce the initialization time of the voice coil motor, reduce the waiting time after the camera lens equipped with the voice coil motor is powered on, thereby improving the use experience of the camera lens, and further improving the product quality of the camera lens.

[0025] The computer-readable storage medium according to the present application stores a voice coil motor control program, and when the voice coil motor control program is executed by a processor, the above-mentioned voice coil motor control method is implemented.

[0026] For the computer-readable storage medium according to the present application, when the voice coil motor control program stored therein is executed by a processor when the camera lens is equipped with a voice coil motor and the camera lens is powered on, the initialization time of the voice coil motor can be reduced, and the waiting time after the camera lens is powered on can be reduced, thereby improving the use experience of the camera lens, and further improving the product quality of the camera lens.

[0027] The camera lens according to the present application includes: a base and a movable seat. The movable seat is used for mounting a lens, and the movable seat is coaxially arranged with the base; a voice coil motor, the voice coil motor includes a magnetic member and a coil. The coil is installed on the magnetic member, and the coil is fixedly connected to the movable seat. The yoke is fixedly connected to the base. The coil is adapted to move relative to the magnetic member along the axial direction of the movable seat to drive the movable seat to move relative to the base along the axial direction of the movable seat; a memory, a processor, and a voice coil motor control program stored on the memory and executable on the processor. When the processor executes the voice coil motor control program, the above-mentioned voice coil motor control method is implemented to enable the camera lens to autofocus.

[0028] For the camera lens according to the present application, when the camera lens is powered on, by the processor executing the voice coil motor control program stored on the memory, the initialization time of the voice coil motor can be reduced, and the waiting time after the camera lens is powered on can be reduced, thereby improving the use experience of the camera lens and further improving the product quality of the camera lens. Description of the Drawings

[0029] Figure 1 is a flowchart of the voice coil motor control method according to an embodiment of the present application;

[0030] Figure 2 is a schematic diagram of the camera lens according to an embodiment of the present application;

[0031] Figure 3 is a top view of the camera lens according to an embodiment of the present application;

[0032] Figure 4 is a schematic diagram of the first embodiment when the first detection member moves relative to the induction magnet according to an embodiment of the present application;

[0033] Figure 5 is a schematic diagram of the second embodiment when the first detection member moves relative to the induction magnet according to an embodiment of the present application;

[0034] Figure 6 is a schematic diagram when the second detection member or the third detection member moves relative to the magnetic grating according to an embodiment of the present application;

[0035] Figure 7 is a waveform diagram of the first detection signal and the second detection signal according to an embodiment of the present application;

[0036] Figure 8 is a block diagram of the voice coil motor control system according to an embodiment of the present application;

[0037] Figure 9 is a block diagram of the processor, memory, communication interface, and communication bus according to an embodiment of the present application.

[0038] In the figure, 1000 is a camera lens; 100 is a voice coil motor; 200 is a base; 300 is a movable seat;

[0039] 1 is a magnetic member; 2 is a coil; 3 is a first detection member; 4 is a second detection member; 5 is a third detection member; 6 is an induction magnet; 7 is a magnetic grating; 71 is a magnetic pole unit;

[0040] 400 is a voice coil motor control system; 10 is a detection module; 20 is a signal receiving module; 30 is a power supply module; 40 is a cycle accumulation module; 50 is a calculation module; 60 is a judgment module;

[0041] Processor 1201; communication interface 1202; memory 1203; communication bus 1204. Detailed implementation manners

[0042] The following will further describe in detail the specific implementation manners of the present application in conjunction with the accompanying drawings and embodiments. The following embodiments are used to illustrate the present application, but are not used to limit the scope of the present application.

[0043] As Figures 1-9 shown, a voice coil motor control method according to an embodiment of the present application is applicable to a device equipped with a voice coil motor 100. For example, the voice coil motor control method is applicable to a camera lens 1000 or a material transportation platform in industry, etc. The following will illustrate the present application by taking the voice coil motor 100 installed in the camera lens 1000 as an example.

[0044] As Figure 2 、 Figure 3 shown, the voice coil motor 100 includes a magnetic member 1 and a coil 2. Along the first direction, the magnetic member 1 has opposite first and second ends. The coil 2 is adapted to move relative to the magnetic member 1 along the first direction. Specifically, the magnetic member 1 can be configured as a yoke, and a permanent magnet is installed on the yoke. The magnetic member 1 can generate a magnetic field, and at least part of the structure of the coil 2 passes through the magnetic field. When the coil 2 is energized, the coil 2 is subjected to an electromagnetic force and moves relative to the magnetic member 1. When the voice coil motor 100 is installed in the camera lens 1000, the camera lens 1000 further includes a base 200 and a movable seat 300. The base 200 and the movable seat 300 are coaxially arranged. The movable seat 300 is used to mount a lens. The base 200 is fixedly connected to the magnetic member 1, and the movable seat 300 is fixedly connected to the coil 2. When the coil 2 moves relative to the magnetic member 1, the movable seat 300 is driven to move relative to the base 200. However, the present application is not limited thereto. For example, in some embodiments, the base 200 is fixedly connected to the coil 2, and the movable seat 300 is fixedly connected to the magnetic member 1. In this way, the technical effect that the movable seat 300 moves relative to the base 200 when the coil 2 moves relative to the magnetic member 1 can also be achieved.

[0045] And, as Figure 2 、Figure 3 As shown, when the voice coil motor 100 is installed in the camera lens 1000, the first direction may refer to the axial direction of the camera lens 1000, and the axial direction of the camera lens 1000 may be Figure 2 the up and down direction in Figure 2 the lower end of the magnetic member 1 in Figure 2 and the upper end of the magnetic member 1 in Figure 1 As shown, the voice coil motor control method according to an embodiment of the present application includes the following steps:

[0046] S1. Obtain the first initial value of the first detection signal at the initial moment, and determine the initial relative position between the coil 2 and the magnetic member 1 according to the first initial value. It should be noted that the moment immediately after the voice coil motor 100 is powered on is the above-mentioned initial moment. In the direction from the first end to the second end, the value of the first detection signal changes monotonically and continuously. That is to say, the value of the first detection signal and the relative position between the coil 2 and the magnetic member 1 correspond one by one. The voice coil motor control method can determine the initial relative position between the coil 2 and the magnetic member 1 by means of look-up table or calculation using a calculation formula, etc. After the camera lens 1000 determines the initial relative position between the coil 2 and the magnetic member 1 using the first initial value, it can perform a focusing operation, and the coil 2 does not need to move relative to the magnetic member 1 to the initial calibration position, thereby reducing the initialization time of the voice coil motor 100 and reducing the waiting time after the camera lens 1000 equipped with the voice coil motor 100 is powered on.

[0047] S2. In response to the position adjustment signal, determine the target movement position and the preset displacement amount of the coil 2 relative to the magnetic member 1 according to the position adjustment signal. Among them, the camera can send a position adjustment signal. When the coil 2 moves relative to the magnetic member 1 to the target movement position, the position of the lens in the camera lens 1000 is adjusted to an appropriate focusing position.

[0048] S3. Control the coil 2 to move relative to the magnetic member 1, obtain a plurality of second detection signals at the current moment, and calculate and obtain the real-time phase value of the coil 2 within the current cycle period of the second detection signal according to the plurality of second detection signals at the current moment. Among them, the value period of each second detection signal changes continuously, and there is a preset phase difference between any two adjacent second detection signals. The value of the second detection signal changes with the displacement amount of the coil 2. Moreover, when the coil 2 is located at the initial relative position relative to the magnetic member 1, the detected value of the second detection signal is the initial value of the second detection signal. When the coil 2 moves relative to the magnetic member 1 and the detected values of the plurality of second detection signals reach the initial value again, it is proved that the second detection signal completes an output of a cycle period.

[0049] By simultaneously obtaining multiple second detection signals, the control accuracy of the voice coil motor control method for controlling the voice coil motor 100 can be improved, so that the coil 2 can accurately move to the target movement position. At the same time, since the first detection signal monotonically changes, through the cooperation of the first detection signal and the second detection signal, the real-time detection value of the first detection signal can be used to determine whether the coil 2 moves close to the target movement position. Of course, in this application, by obtaining the second detection signal in real time, the moving direction of the coil 2 relative to the magnetic member 1 can also be determined.

[0050] In addition, when there are multiple output values with the same numerical value as the initial value within one cycle period of the second detection signal, by simultaneously obtaining multiple second detection signals and making all the multiple second detection signals reach the initial value, it can be determined whether the second detection signal completes one cycle period.

[0051] S4. Obtain the integral position cycle number of the second detection signal at the current moment. It should be noted that when the second detection signal completes one cycle of output, the numerical value of the integral position cycle number of the second detection signal is incremented by 1. An accumulator can be used to accumulate and calculate the integral position cycle number of the second detection signal, and the integral position cycle number of the second detection signal can be obtained by reading the data of the accumulator. In some embodiments of this application, by obtaining the second detection signal in real time and comparing the read value of the second detection signal at the current moment with that at the previous moment, it can be determined whether the integral position cycle number of the second detection signal changes at the current moment.

[0052] Calculate and obtain the actual displacement of the coil 2 relative to the magnetic member 1 according to the integral position cycle number of the second detection signal at the current moment, the unit displacement of the coil 2 within each cycle period of the second detection signal, and the real-time phase value. In this way, the displacement between the initial relative position of the coil 2 relative to the magnetic member 1 and the relative position at the current moment can be determined.

[0053] S5. Based on the preset displacement and the actual displacement, control the coil 2 to move towards the target movement position based on a preset closed-loop control algorithm. When the difference between the preset displacement and the actual displacement is less than the preset displacement error threshold, control the coil 2 to stop moving. In this way, the voice coil motor control method can control the coil 2 to complete initialization and control the coil 2 to move to the target movement position.

[0054] After completing step S5, in some embodiments, the preset closed-loop control algorithm can be used to continue to control the coil 2 so that the coil 2 relative to the magnetic member 1 is maintained as much as possible at the original target movement position. In other embodiments, the preset closed-loop control algorithm can be used to control the coil 2 to move relative to the magnetic member 1 towards a new target movement position.

[0055] The preset closed-loop control algorithm can be a PID control (proportional-integral-derivative control) algorithm. The specific PID control algorithm can be set according to the actual usage scenario, and the PID control algorithm is well reflected in the prior art and will not be elaborated here. Moreover, the preset displacement error threshold can be set according to the actual usage scenario and the operating accuracy of the device. By using the preset closed-loop control algorithm to control the coil 2 to move towards the target moving position, the coil 2 can be quickly and accurately moved to the target moving position.

[0056] Thus, by obtaining the first detection signal and the second detection signal, using the first initial value of the first detection signal to determine the initial relative position between the coil 2 and the magnetic member 1, and using the second detection signal to control the coil 2 to accurately move towards the target moving position relative to the magnetic member 1. Compared with the prior art, when the voice coil motor 100 of the present application is initialized, there is no need to perform zero calibration, which can reduce the initialization time of the voice coil motor 100 and reduce the waiting time after the camera lens 1000 equipped with the voice coil motor 100 is powered on, thereby improving the usage experience of the camera lens 1000 and further improving the product quality of the camera lens 1000.

[0057] In some embodiments of the present application, before responding to the position adjustment signal, it further includes:

[0058] S101. Determine the initial rough position interval of the coil 2 according to the first detection signal, where the moving stroke range of the coil 2 relative to the magnetic member 1 can be divided into multiple sequentially arranged rough position intervals.

[0059] S102. Obtain the second initial values of the multiple second detection signals at the initial moment, and determine the initial precise position interval of the coil 2 according to the multiple second initial values. Among them, each rough position interval of the coil 2 corresponds to multiple precise position intervals, and the moving stroke range of the coil 2 relative to the magnetic member 1 can be divided into multiple sequentially arranged precise position intervals. For example, in some embodiments, the moving stroke range of the coil 2 relative to the magnetic member 1 is 100 mm. At this time, the moving stroke range of the coil 2 relative to the magnetic member 1 can be divided into 10 sequentially arranged rough position intervals and 100 sequentially arranged precise position intervals. Each rough position interval corresponds to 10 sequentially arranged precise position intervals, and moreover, the length of each rough position interval is equal, and the length of each precise position interval is equal. By the cooperation of the first detection signal and the second detection signal, the initial relative position of the coil 2 relative to the magnetic member 1 can be accurately positioned, which helps to improve the operating accuracy of the voice coil motor 100.

[0060] Such as Figures 2-5As shown, in some embodiments of the present application, the voice coil motor 100 includes a first detecting member 3 and an induction magnet 6. The first detecting member 3 can be a magnetic field sensor. The induction magnet 6 extends along a first direction (i.e., Figure 2 the up and down direction in

[0061] ). The first detecting member 3 is disposed opposite to the induction magnet 6. The first detecting member 3 is used to detect the magnetic induction intensity on the corresponding side of the induction magnet 6 and generate a first detection signal. Among them, the magnetic induction intensity of the induction magnet 6 detected by the first detecting member 3 can be the magnetic induction intensity of the induction magnet 6. When the detected position of the induction magnet 6 is the positive pole, the first detection signal output by the first detecting member 3 is a positive value. When the detected position of the induction magnet 6 is the negative pole, the first detection signal output by the first detecting member 3 is a negative value. Figure 4 As shown, the induction magnet 6 can be formed by splicing two magnets with the same structural dimensions and the same magnetic induction intensity along the first direction. In this way, the polarities of the two ends of the induction magnet 6 can be different, and the magnetic induction intensity of the induction magnet 6 changes uniformly, so that the value of the first detection signal can change monotonically and continuously.

[0062] As Figure 5 shown, in some other embodiments, on the side of the induction magnet 6 opposite to the first detecting member 3, the polarity of the first end of the induction magnet 6 close to the magnetic member 1 is the same as the polarity of the second end close to the magnetic member 1, and in the direction from the first end to the second end, the magnetic induction intensity of the induction magnet 6 changes monotonically. At this time, the induction magnet 6 can be composed of a single magnet. The first detecting member 3 is facing the positive or negative pole of the induction magnet 6. In the direction from the first end to the second end of the magnetic member 1, the cross-sectional area of the induction magnet 6 gradually changes. Specifically, as Figure 5 shown, in the direction from the first end to the second end of the magnetic member 1, when the cross-sectional area of the induction magnet 6 gradually increases, when the coil 2 moves from the first end to the second end of the magnetic member 1, the absolute value of the output value of the first detecting member 3 gradually increases.

[0063] In some other embodiments, in the direction from the first end to the second end of the magnetic member 1, when the cross-sectional area of the induction magnet 6 gradually decreases, when the coil 2 moves from the first end to the second end of the magnetic member 1, the absolute value of the output value of the first detecting member 3 gradually decreases. Such a design can also make the value of the first detection signal change monotonically and continuously.

[0064] In some embodiments, such as Figure 2 , Figure 3 the second detection signals obtained can be two. The second detection signals include a first detection sub-signal and a second detection sub-signal. The voice coil motor 100 includes a second detection member 4 and a third detection member 5. Both the second detection member 4 and the third detection member 5 can be magnetic field sensors. When the coil 2 moves relative to the magnetic member 1, the second detection member 4 generates a first detection sub-signal corresponding to the displacement amount of the coil 2, and the third detection member 5 generates a second detection sub-signal corresponding to the displacement amount of the coil 2. The second detection member 4 and the third detection member 5 are arranged at intervals along the first direction (i.e., Figure 2 the up-down direction in

[0065] ). By arranging the second detection member 4 and the third detection member 5 at intervals, it can be ensured that the second detection member 4 and the third detection member 5 generate output values synchronously, thereby improving the accuracy of controlling the movement of the coil 2 by the voice coil motor control method.

[0066] The unit displacement amount of the coil 2 in each cycle period of the second detection signal is P, the interval distance between the second detection member 4 and the third detection member 5 is z1, and the preset phase difference between the first detection sub-signal and the second detection sub-signal is A. P, z1, and A satisfy the relational expression: A = 2πz1 / P. Figure 7 As Figure 7 shown, taking the initial relative position of the coil 2 relative to the magnetic member 1 as the zero point, with the displacement amount of the coil 2 as the horizontal axis and the output values of the detection signals (i.e., the first detection signal and the second detection signal) as the vertical axis to establish a coordinate system,

[0067]

[0068] The output value Va of the first detection sub-signal and the output value Vb of the second detection sub-signal satisfy the relational expressions: Va = K*sin(2πz / P); Vb = K*sin(2πz / P + A), where K is the preset signal amplitude, and the numerical setting of the preset signal amplitude is related to the maximum value of the corresponding parameters of the detected component. At this time, the phase value calculated through the second detection signal is the phase angle. And, in order to verify whether the output values of the first detection sub-signal and the second detection sub-signal complete the cycle period, A can satisfy the relational expression: 0 < A < 2π. In some preferred embodiments, A = π / 2. At this time, the output value Vb of the second detection sub-signal satisfies the relational expression: K*cos(2πz / P), which helps to reduce the calculation difficulty of the control method for calculating the displacement amount of the coil 2 in real time, thereby making the control method more concise.Further, based on multiple second detection signals at the current moment, calculate and obtain the real-time displacement of coil 2 within the current cycle of the second detection signal, including the following steps:

[0069] S301. Calculate and obtain the amplitude Va of the first detection sub-signal within the current cycle according to the first real-time output value of the first detection sub-signal at the current moment, and calculate and obtain the amplitude Vb of the second detection sub-signal within the current cycle according to the second real-time output value of the second detection sub-signal at the current moment.

[0070] S302. Calculate and obtain the real-time phase value θ of the coil within the current cycle of the second detection signal according to the amplitude Va of the first detection sub-signal within the current cycle and the amplitude Vb of the second detection sub-signal within the current cycle. t Among them, the integer position cycle number of the second detection signal at the current moment is N. t The corresponding real-time phase value is θ. t The real-time displacement z of coil 2 within the current cycle of the second detection signal, θ and z satisfy the relationship: θ = arctan(Va / Vb); z = N·P + Pθ / 2π.

[0071] Further, obtain the integer position cycle number of the second detection signal at the current moment, including the following steps:

[0072] S401. Obtain the integer position cycle number N and the real-time phase value θ of the second detection signal at the previous moment. The integer position cycle number N and the real-time phase value θ at the previous moment can be stored in a temporary storage medium after being calculated and obtained at the previous moment, and after calculating and obtaining the integer position cycle number N and the real-time phase value θ at the current moment, the integer position cycle number N and the real-time phase value θ can be stored in the temporary storage medium for use when calculating and obtaining the integer position cycle number N and the real-time phase value θ at the next moment. t-1 and the real-time phase value θ t-1 The integer position cycle number N t-1 and the real-time phase value θ t-1 can be stored in a temporary storage medium after being calculated and obtained at the previous moment, and after calculating and obtaining the integer position cycle number N t and the real-time phase value θ t at the current moment, the integer position cycle number N t and the real-time phase value θ t can be stored in the temporary storage medium for use when calculating and obtaining the integer position cycle number N t+1 and the real-time phase value θ t+1 at the next moment.

[0073] S402. Judge whether θ t and θ t-1 satisfy the relationship: θ t > θ t-1 and 0 ≤ θ t-1 < π / 2, and 3π / 2 < θ t ≤ 2π. If satisfied, then N t and N t-1 satisfy the relationship: N t = Nt-1 -1。

[0074] S403. If not satisfied, then judge θ t and θ t-1 whether satisfy the relational expression: θ t <θ t-1 , and 3π / 2 < θ t-1 ≤ 2π, and 0 ≤ θ t < π / 2. If satisfied, then N t and N t-1 satisfy the relational expression: N t = N t-1 +1.

[0075] S404. If not satisfied, then N t and N t-1 satisfy the relational expression: N t = N t-1 . Wherein, at any two adjacent detection moments of the second detection signal, θ t-1 and θ t satisfy the relational expression: 0 ≤ |θ t -θ t-1 | ≤ π / 2. Thus, by comparing the real-time phase value θ t calculated at the current moment and θ t-1 at the previous moment, it can be determined whether the integer position cycle number N t at the current moment has changed. Furthermore, by cooperating with the first detection signal and the second detection signal, the displacement of the coil 2 can be accurately obtained, thereby reducing the movement error of the coil 2, and further improving the autofocus effect of the camera lens 1000.

[0076] Based on this, the voice coil motor control method can control the movement or stillness of the coil 2 according to the actual displacement of the coil 2.

[0077] Furthermore, as Figure 2 , Figure 3 , Figure 6As shown, the voice coil motor 100 may further include a magnetic grating 7. The magnetic grating 7 has a plurality of magnetic pole units 71 arranged in sequence along a first direction. The second detection member 4 and the third detection member 5 are both disposed opposite to the same side wall of the magnetic grating 7. The second detection member 4 is used to detect the magnetic induction intensity on the corresponding side of the magnetic grating 7 and generate a first detection sub-signal. The third detection member 5 is used to detect the magnetic induction intensity on the corresponding side of the magnetic grating 7 and generate a second detection sub-signal. It should be noted that the magnetic induction intensity of the magnetic grating 7 detected by the second detection member 4 and the third detection member 5 may both refer to the magnetic induction intensity at the corresponding position of the magnetic grating 7. Moreover, when the detected position of the magnetic grating 7 is the positive pole, both the first detection sub-signal output by the second detection member 4 and the second detection sub-signal output by the third detection member 5 are positive values. When the detected position of the magnetic grating 7 is the negative pole, the first detection sub-signal output by the second detection member 4 and the second detection sub-signal output by the third detection member 5 are negative values.

[0078] On the side of the magnetic grating 7 opposite to the second detection member 4 and the third detection member 5, the polarities of any two adjacent magnetic pole units 71 are opposite. That is to say, the plurality of magnetic pole units 71 may be sequentially and alternately spliced along the first direction to form the magnetic grating 7. The length dimension of each magnetic pole unit 71 along the first direction is the same, and the magnitude of the magnetic induction intensity of each magnetic pole unit 71 is the same. In this way, it can be ensured that the unit displacement amount P and the preset signal amplitude K in each cycle period of the output value of the first detection sub-signal and the output value of the second detection sub-signal are equal. Thus, the numerical period of each second detection signal can change continuously, and when using the voice coil motor control method, it is possible to judge whether the second detection signal has completed a cycle period according to the output value of the second detection signal.

[0079] Based on this, as Figure 8 shown, the present application further discloses a voice coil motor control system 400. The voice coil motor control system 400 is applicable to the voice coil motor control method of the above embodiment. According to the voice coil motor control system 400 of the embodiment of the present application, it includes: a detection module 10, a signal receiving module 20, a power supply module 30, a cycle accumulation module 40, a calculation module 50, and a judgment module 60.

[0080] The detection module 10 is used to detect and obtain the first detection signal and the second detection signal in real time. The detection module 10 may include the first detection member 3, the second detection member 4, and the third detection member 5 of the above embodiment. Among them, the first detection member 3 is used to detect and obtain the first detection signal, and the second detection member 4 and the third detection member 5 are used to detect and obtain the second detection signal.

[0081] The signal receiving module 20 is used to receive the position adjustment signal. When the voice coil motor 100 is installed on the camera lens 1000, and the camera lens 1000 is installed on the camera, the voice coil motor 100 is directly communicatively connected to the camera, or the voice coil motor 100 is indirectly communicatively connected to the camera through the camera lens 1000. The camera is used to send the position adjustment signal.

[0082] The power supply module 30 is used to supply power to or cut off power from the coil 2 to control the movement of the coil 2 relative to the magnetic member 1. Specifically, the coil 2 is located within the magnetic field of the magnetic member 1. When the power supply module 30 supplies power to the coil 2, the coil 2 is subjected to an electromagnetic force and moves relative to the magnetic member 1. When the power supply module 30 cuts off power from the coil 2, the coil 2 is no longer subjected to the electromagnetic force, and at this time, the coil 2 is stationary relative to the magnetic member 1. The period accumulation module 40 is used to accumulate and calculate the number of full position periods of the second detection signal when the coil 2 moves towards the target moving position. Among them, the period accumulation module 40 can be an accumulator.

[0083] The calculation module 50 is used to determine the initial relative position between the coil 2 and the magnetic member 1 according to the first initial value of the first detection signal at the initial moment, and is also used to determine the target moving position and the preset displacement amount of the coil 2 relative to the magnetic member 1 according to the position adjustment signal. It is also used to calculate and obtain the real-time phase value of the coil 2 within the current cycle period of the second detection signal according to the second detection signal at the current moment, and is also used to calculate and obtain the actual displacement amount of the coil 2 relative to the magnetic member 1 according to the number of full position periods of the second detection signal at the current moment, the unit displacement amount of the coil 2 within each cycle period of the second detection signal, and the real-time phase value.

[0084] The judgment module 60 is used to judge whether the difference between the preset displacement amount and the actual displacement amount is less than the preset displacement error threshold. When the judgment module 60 determines that the difference between the preset displacement amount and the actual displacement amount is greater than or equal to the preset displacement error threshold, the power supply module 30 continues to supply power to the coil 2 to make the coil 2 move towards the target moving position. When the judgment module 60 determines that the difference between the preset displacement amount and the actual displacement amount is less than the preset displacement error threshold, the power supply module 30 cuts off power from the coil 2.

[0085] According to the voice coil motor control system 400 of the embodiments of the present application, the voice coil motor control system 400 corresponds to the voice coil motor control method of the above embodiments. The detection module 10 is used to obtain a first detection signal and a second detection signal. The calculation module 50 uses the first initial value of the first detection signal to determine the initial relative position between the coil 2 and the magnetic member 1, and uses the second detection signal to control the coil 2 to accurately move relative to the magnetic member 1 towards the target moving position. Compared with the prior art, when the voice coil motor 100 of the present application is initialized, zero calibration is not required, which can reduce the initialization time of the voice coil motor 100 and reduce the waiting time after the camera lens 1000 equipped with the voice coil motor 100 is powered on. Thus, the user experience of the camera lens 1000 can be improved, and further the product quality of the camera lens 1000 can be improved.

[0086] Based on this, the present application further discloses a computer-readable storage medium. According to the computer-readable storage medium of the embodiments of the present application, a voice coil motor control program is stored thereon. When the voice coil motor control program is executed by a processor, the voice coil motor control method of the above embodiments is implemented.

[0087] According to the computer-readable storage medium of the embodiments of the present application, when the camera lens 1000 is equipped with the voice coil motor 100 and the camera lens 1000 is powered on, when the stored voice coil motor control program is executed by the processor, the initialization time of the voice coil motor 100 can be reduced, and the waiting time after the camera lens 1000 is powered on can be reduced. Thus, the user experience of the camera lens 1000 can be improved, and further the product quality of the camera lens 1000 can be improved.

[0088] As Figure 9 shown, based on this, the present application further discloses a camera lens 1000. According to the camera lens 1000 of the embodiments of the present application, it includes: a base 200, a movable seat 300, a voice coil motor 100, a memory, a processor, and a voice coil motor control program stored on the memory and operable on the processor.

[0089] The movable seat 300 is used for mounting lenses. The movable seat 300 is coaxially arranged with the base 200. The voice coil motor 100 includes a magnetic member 1 and a coil 2. The coil 2 is mounted on the magnetic member 1, and the coil 2 is fixedly connected to the movable seat 300. The yoke is fixedly connected to the base 200. The coil 2 is adapted to move axially along the movable seat 300 relative to the magnetic member 1 to drive the movable seat 300 to move axially relative to the base 200. When the processor executes the voice coil motor control program, the voice coil motor control method of the above embodiments is implemented to enable the camera lens 1000 to autofocus.

[0090] According to the camera lens 1000 of the embodiment of the present application, when the camera lens 1000 is powered on, by executing the voice coil motor control program stored on the memory by the processor, the initialization time of the voice coil motor 100 can be reduced, and the waiting time after the camera lens 1000 is powered on can be reduced, thereby improving the user experience of the camera lens 1000 and further improving the product quality of the camera lens 1000. As Figure 9 shown, the camera lens includes at least one processor 1201, at least one communication interface 1202, at least one memory 1203 and at least one communication bus 1204; in the embodiment of the present application, the number of the processor 1201, the communication interface 1202, the memory 1203, and the communication bus 1204 is at least one, and the processor 1201, the communication interface 1202, and the memory 1203 complete mutual communication through the communication bus 1204.

[0091] Among them, the memory 1203 can be, but is not limited to, random access memory (RAM), read only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), etc. Among them, the memory 1203 is used to store programs, and after receiving the execution instruction, the processor 1201 executes the programs to implement the steps of the voice coil motor control method described in the above embodiments.

[0092] The processor 1201 may be an integrated circuit chip with signal processing capabilities. The above-mentioned processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. It can implement or execute the various methods, steps and logic block diagrams disclosed in the embodiments of the present invention. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0093] Note that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch instructions from the instruction execution system, apparatus, or device and execute the instructions), or used in combination with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then stored in a computer memory.

[0094] It should be understood that various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, multiple steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits with logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits with suitable combinational logic gate circuits, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0095] The center of the movable seat 300 in the present invention may also not be provided with a lens, so that the voice coil motor control method controls the voice coil motor to drive the movable seat 300 to achieve other functions. For example, driving the lens to reflect the laser to change the position where the laser is reflected.

[0096] The above are only the preferred embodiments of the present application. It should be noted that for those of ordinary skill in the art in this technical field, without departing from the technical principle of the present application, several improvements and substitutions can be made, and these improvements and substitutions should also be regarded as the protection scope of the present application.

Claims

1. A voice coil motor control method, the voice coil motor comprising a magnetic member and a coil, the magnetic member having opposite first and second ends in a first direction, the coil being adapted to move relative to the magnetic member in the first direction, characterized in that, The voice coil motor control method includes: Obtaining a first initial value of a first detection signal at an initial moment, and determining an initial relative position between the coil and the magnetic member according to the first initial value; In response to a position adjustment signal, determining a target movement position and a preset displacement amount of the coil relative to the magnetic member according to the position adjustment signal; Controlling the movement of the coil relative to the magnetic member, obtaining a plurality of second detection signals at the current moment, and calculating and obtaining a real-time phase value of the coil within the current cycle period of the second detection signals according to the plurality of second detection signals at the current moment; Obtaining an integer position cycle number of the second detection signal at the current moment, and calculating and obtaining an actual displacement amount of the coil relative to the magnetic member according to the integer position cycle number at the current moment, the unit displacement amount of the coil within each cycle period of the second detection signal, and the real-time phase value; Based on the preset displacement amount and the actual displacement amount, controlling the coil to move towards the target movement position based on a preset closed-loop control algorithm, and when the difference between the preset displacement amount and the actual displacement amount is less than a preset displacement error threshold, controlling the coil to stop moving; Wherein, in the direction from the first end to the second end, the value of the first detection signal changes monotonically and continuously, the value of each second detection signal changes periodically and continuously, and there is a preset phase difference between any two adjacent second detection signals.

2. The voice coil motor control method according to claim 1, wherein Before the response to the position adjustment signal, it further includes: Determining an initial rough position interval of the coil according to the first detection signal; Obtaining second initial values of a plurality of the second detection signals at the initial moment, and determining an initial precise position interval of the coil according to the plurality of second initial values, wherein each rough position interval of the coil corresponds to a plurality of precise position intervals.

3. The voice coil motor control method according to claim 1 or 2, characterized in that, The voice coil motor includes a first detection member and an induction magnet, the induction magnet is arranged to extend along the first direction, the first detection member is arranged opposite to the induction magnet, and the first detection member is used for detecting the magnetic induction intensity on the corresponding side of the induction magnet and generating the first detection signal; On the side of the induction magnet opposite to the first detection member, the polarity of the induction magnet close to the first end is opposite to the polarity close to the second end, and in the direction from the first end to the second end, the magnetic induction intensity of the induction magnet changes monotonically, or, On the side of the induction magnet opposite to the first detection member, the polarity of the induction magnet close to the first end is the same as the polarity close to the second end, and in the direction from the first end to the second end, the magnetic induction intensity of the induction magnet changes monotonically.

4. The voice coil motor control method according to claim 1 or 2, characterized in that, The second detection signal includes a first detection sub-signal and a second detection sub-signal, the voice coil motor includes a second detection member and a third detection member, when the coil moves relative to the magnetic member, the second detection member generates the first detection sub-signal corresponding to the displacement amount of the coil, the third detection member generates the second detection sub-signal corresponding to the displacement amount of the coil, and the second detection member and the third detection member are arranged at intervals along the first direction; The unit displacement of the coil within each cycle of the second detection signal is P, the distance between the second detection member and the third detection member is z1, and the preset phase difference between the first detection sub-signal and the second detection sub-signal is A. P, z1, and A satisfy the relationship: A = 2πz1 / P; The output value Va of the first detection sub-signal and the output value Vb of the second detection sub-signal satisfy the relationship: Va = K*sin(2πz / P); Vb = K*sin(2πz / P + A), where K is the preset signal amplitude.

5. The voice coil motor control method according to claim 4, wherein, Calculating and obtaining the real-time phase value of the coil within the current cycle of the second detection signal according to multiple second detection signals at the current moment includes: Calculating and obtaining the amplitude Va of the first detection sub-signal within the current cycle according to the first real-time output value of the first detection sub-signal at the current moment, and calculating and obtaining the amplitude Vb of the second detection sub-signal within the current cycle according to the second real-time output value of the second detection sub-signal at the current moment; Calculate and obtain the real-time phase value θ of the coil in the current cycle of the second detection signal according to the amplitude Va of the first detection sub-signal in the current cycle and the amplitude Vb of the second detection sub-signal in the current cycle t , where t is the current time.

6. The voice coil motor control method according to claim 5, wherein, The integer position cycle number of the second detection signal at the current moment is N t , obtaining the integer position cycle number of the second detection signal at the current moment includes: Obtain the integer position cycle number N of the second detection signal at the previous moment t-1 and the real-time phase value θ t-1 ; Judge θ t and θ t-1 whether they satisfy the relational expression: θ t > θ t-1 , and 0 ≤ θ t-1 < π / 2, and 3π / 2 < θ t ≤ 2π. If satisfied, then N t and N t-1 satisfy the relational expression: N t = N t-1 - 1; If not satisfied, then judge θ t and θ t-1 whether satisfy the relational expression: θ t <θ t-1 , and 3π / 2 < θ t-1 ≤ 2π, and 0 ≤ θ t < π / 2. If satisfied, then N t and N t-1 satisfy the relational expression: N t = N t-1 +1; If not satisfied, then N t and N t-1 satisfy the relation: N t = N t-1 ; Among them, at any two adjacent detection times of the second detection signal, θ t-1 and θ t satisfy the relational expression: 0 ≤ |θ t - θ t-1 | ≤ π / 2.

7. The voice coil motor control method according to claim 6, wherein The voice coil motor further includes a magnetic grating, the magnetic grating has a plurality of magnetic pole units arranged in sequence along the first direction, the second detection member and the third detection member are both oppositely arranged relative to the same side wall of the magnetic grating, the second detection member is used to detect the magnetic induction intensity on the corresponding side of the magnetic grating and generate the first detection sub-signal, and the third detection member is used to detect the magnetic induction intensity on the corresponding side of the magnetic grating and generate the second detection sub-signal; On the side of the magnetic grating opposite to the second detection member and the third detection member, the polarities of any two adjacent magnetic pole units are opposite, the length dimension of each magnetic pole unit along the first direction is the same, and the magnitude of the magnetic induction intensity of each magnetic pole unit is the same.

8. A voice coil motor control system, applicable to the voice coil motor control method according to any one of claims 1-7, characterized in that The voice coil motor control system includes: A detection module, configured to detect and obtain the first detection signal and the second detection signal in real time; A signal receiving module, configured to receive a position adjustment signal; A power supply module, configured to supply power to or cut off power from the coil to control the movement of the coil relative to the magnetic member; A cycle accumulation module, configured to accumulate and calculate the number of full-position cycles of the second detection signal when the coil moves towards the target moving position; A calculation module, configured to determine the initial relative position between the coil and the magnetic member according to the first initial value of the first detection signal at the initial moment, and is further configured to determine the target moving position and the preset displacement of the coil relative to the magnetic member according to the position adjustment signal, and is further configured to calculate and obtain the real-time phase value of the coil within the current cycle of the second detection signal according to the second detection signal at the current moment, and is further configured to calculate and obtain the actual displacement of the coil relative to the magnetic member according to the number of full-position cycles of the second detection signal at the current moment, the unit displacement of the coil within each cycle of the second detection signal, and the real-time phase value; A judgment module, configured to judge whether the difference between the preset displacement and the actual displacement is less than the preset displacement error threshold.

9. A computer-readable storage medium, characterized in that, A voice coil motor control program is stored thereon. When the voice coil motor control program is executed by a processor, it implements the voice coil motor control method according to any one of claims 1-7.

10. A camera lens, characterized in that, Comprising: A base and a movable seat, the movable seat is used for mounting a lens, and the movable seat is coaxially arranged with the base; A voice coil motor, the voice coil motor includes a magnetic member and a coil, the coil is mounted on the magnetic member, and the coil is fixedly connected to the movable seat, the yoke is fixedly connected to the base, and the coil is adapted to move axially along the movable seat relative to the magnetic member to drive the movable seat to move axially relative to the base; A memory, a processor, and a voice coil motor control program stored on the memory and executable on the processor. When the processor executes the voice coil motor control program, it implements the voice coil motor control method according to any one of claims 1-7 to enable the camera lens to autofocus.

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