IC chip, control method, and generation method

Abstract

SOLUTION: To provide an IC chip for controlling a driving mechanism that drives an optical element according to a control signal, wherein said IC chip comprises a generation part for generating the control signal for moving the optical element to a target position, while suppressing sound generated in accompany with drive of the driving mechanism, on the basis of relationship information indicating a relationship between an indicator corresponding to the magnitude of sound generated in accompany with drive of the driving mechanism and a position of the optical element.SELECTED DRAWING: Figure 2A

Description

[Technical field]

[0001] The present invention relates to an IC chip, a control method, and a production method. [Background technology]

[0002] Patent Document 1 describes a motion device control circuit that stably operates a motion device and has a short convergence time when moving the motion device to a target position, regardless of the magnitude of the differential amount of the target value. Patent Document 2 describes a position control device that corrects the driving force applied to a voice coil motor to suppress a decrease in driving force generated in the surrounding area of ​​the moving part, thereby improving tracking performance. [Prior art document] [Patent documents] [Patent Document 1] Patent No. 6360388 [Patent Document 2] Patent No. 5259851 Summary of the Invention [Problem to be solved by the invention]

[0003] When the driving mechanism moves the optical element to a target position, it is desirable to suppress noise generated by the driving mechanism. [Means for solving the problem]

[0004] In a first aspect of the present invention, there is provided an IC chip for controlling a drive mechanism that drives an optical element based on a control signal, the IC chip including a generation unit that generates the control signal for moving the optical element to a target position while suppressing sound generated by driving the drive mechanism, based on a detection signal indicating the position of the optical element and relationship information indicating the relationship between an index according to the volume of sound generated by driving the drive mechanism and the position of the optical element.

[0005] In the IC chip, the generation unit may generate the control signal corresponding to the position of the optical element based on the relationship information in order to suppress noise generated by driving the driving mechanism by suppressing the speed or acceleration at which the optical element moves.

[0006] In any of the IC chips, the generation unit may generate the control signal corresponding to the position of the optical element based on the relationship information in order to suppress at least one of the magnitude of the rate of change of the current supplied to the driving mechanism and the magnitude of the current, thereby suppressing sound generated by driving the driving mechanism.

[0007] In any of the IC chips, the relationship information may indicate, as the index, a correction coefficient for correcting the control signal according to a volume of a sound generated by driving the drive mechanism. The generation unit may specify a position of the optical element based on at least one of the detection signal and a target position signal indicating the target position, specify the correction coefficient corresponding to the specified position of the optical element by referring to the relationship information, and generate the control signal based on the correction coefficient according to the position of the optical element, the target position signal, and the detection signal.

[0008] In any of the IC chips, the generation unit may generate the control signal for PID control of the drive mechanism by performing arithmetic operations on at least one of a proportional component, a differential component, and an integral component based on a deviation between the target position signal and the detection signal, based on the correction coefficient corresponding to the position of the optical element, the target position signal, and the detection signal.

[0009] In any one of the IC chips, the generation unit may generate the control signal for correcting a gain of a driving band of the driving mechanism by four arithmetic operations using the correction coefficient according to the position of the optical element. The driving band may indicate 200 Hz or less.

[0010] Any of the IC chips may further include a storage unit that stores the related information.

[0011] Any of the IC chips may be operable in a correction mode in which the control signal is corrected based on the relationship information and a non-correction mode in which the control signal is not corrected based on the relationship information. The generating unit may generate the control signal for moving the optical element to a target position while suppressing a sound generated by driving the driving mechanism, based on the detection signal and the relationship information, while the IC chip is operating in the correction mode.

[0012] Any of the IC chips may further include a magnetic sensor that outputs the detection signal. The magnetic sensor may include a plurality of Hall elements.

[0013] In any of the IC chips, the relationship information may indicate, as the index, a correction coefficient for correcting the control signal according to the loudness of a sound generated by driving the drive mechanism. The generation unit may generate the control signal based on the correction coefficient according to the position of the optical element, a target position signal indicating the target position, and the detection signal. The IC chip may further include a calibration unit that generates or updates the relationship information based on sound information indicating the loudness of a sound generated according to the position of the optical element by driving the drive mechanism according to predetermined drive conditions, and correction coefficient information indicating the relationship between the loudness of the sound and the correction coefficient.

[0014] In any of the IC chips, the predetermined drive conditions may include a step width indicating a distance by which the optical element is moved according to the target position, and an update period for the target position.

[0015] In any of the IC chips, the calibration unit may execute, for each of the step widths or update periods, a process of generating or updating the relationship information by adjusting a correction coefficient for suppressing a sound generated before and after the optical element starts to drive, so that a rate of change of a current supplied to the drive mechanism is reduced when the sound generated before and after the optical element starts to drive is equal to or greater than a predetermined volume. When the sound generated while the optical element is driven in accordance with the drive mechanism is equal to or greater than a predetermined volume, the calibration unit may execute, for each of the step widths or update periods, a process of generating or updating the relationship information by adjusting a correction coefficient for suppressing the sound, so that a rate of change or a magnitude of a drive speed of the drive mechanism is suppressed when the sound generated before and after the optical element starts to drive is equal to or greater than a predetermined volume.

[0016] In any of the IC chips, the calibration unit may identify a frequency component of a sound generated by driving the drive mechanism based on the sound information. When the frequency components of the sound whose loudness is equal to or greater than a predetermined loudness include a frequency component of a first frequency band, the calibration unit may execute a process of generating or updating the relationship information for each of the step widths or update periods by adjusting the correction coefficient so that a rate of change or a magnitude of the drive speed of the drive mechanism is suppressed. When the frequency components of the sound whose loudness is equal to or greater than a predetermined loudness include a frequency component of a second frequency band higher than the first frequency band, the calibration unit may execute a process of generating or updating the relationship information for each of the step widths or update periods by adjusting the correction coefficient so that a rate of change of a current supplied to the drive mechanism is reduced. The first frequency band may be equal to or less than a drive band of the drive mechanism, and the second frequency band may be higher than a drive band of the drive mechanism.

[0017] In a second aspect of the present invention, there is provided a control method for controlling a drive mechanism for driving an optical element based on a control signal, the control method comprising the steps of: generating a control signal for moving the optical element to a target position while suppressing a sound generated by driving the drive mechanism, based on a detection signal indicating a position of the optical element and relationship information indicating a relationship between an index according to a volume of a sound generated by driving the drive mechanism and a position of the optical element.

[0018] In a third aspect of the present invention, there is provided a method for generating relationship information indicating a relationship between a position of an optical element and a correction coefficient of a control signal corresponding to a loudness of a sound generated by driving a drive mechanism, the control signal being referenced by a control device that generates a control signal for controlling a drive mechanism that moves the optical element to a target position while suppressing a sound generated by the drive mechanism. The method includes a step of generating the relationship information based on sound information indicating a loudness of a sound corresponding to a position of the optical element generated by driving the drive mechanism according to a predetermined drive condition, and correction coefficient information indicating a relationship between the loudness of the sound and the correction coefficient.

[0019] In the generation method, the predetermined drive conditions may include a step width indicating a distance by which the optical element is moved according to the target position, and an update period for the target position.

[0020] In any of the generation methods, the generating step may include a step of executing a process of generating the relationship information for each step width or update period by adjusting a correction coefficient for suppressing a sound generated before and after the optical element starts to drive, when the sound is equal to or greater than a predetermined volume, so that a rate of change of the current supplied to the drive mechanism is reduced, and a step of executing a process of generating the relationship information for each step width or update period by adjusting a correction coefficient for suppressing the sound, when the sound generated while the optical element is driven in conjunction with the drive mechanism is equal to or greater than a predetermined volume, so that a rate of change or magnitude of the drive speed of the drive mechanism is suppressed.

[0021] In any of the generating methods, the generating step may include a step of identifying a frequency component of a sound generated by driving the drive mechanism based on the sound information, a step of executing a process of generating the relationship information for each step width or each update period by adjusting the correction coefficient so as to suppress a rate of change or magnitude of the drive speed of the drive mechanism when the frequency components of the sound whose loudness is equal to or greater than a predetermined loudness include frequency components of a first frequency band, and a step of executing a process of generating the relationship information for each step width or each update period by adjusting the correction coefficient so as to reduce a rate of change of a current supplied to the drive mechanism when the frequency components of the sound whose loudness is equal to or greater than a predetermined loudness include frequency components of a second frequency band higher than the first frequency band. The first frequency band may be equal to or less than a drive band of the drive mechanism, and the second frequency band may be higher than a drive band of the drive mechanism.

[0022] The above summary of the invention does not list all of the features of the present invention. Also, subcombinations of these features may also be inventions. [Brief description of the drawings]

[0023] [Figure 1] 1 illustrates an example of the configuration of an imaging device 100. [Figure 2A] 2 is an example of a block diagram showing the configuration of a generating unit 32 and a storage unit 50. FIG. [Figure 2B] 2 is an example of a block diagram showing the configuration of a generating unit 32, a storage unit 50, and a calibration unit 36. FIG. [Diagram 3] 1 is an example of a graph showing the relationship between time and the position of an optical element, and the relationship between time and the volume of a sound. [Figure 4] FIG. 1 is a diagram showing an example of time dependency of the loudness and position of a sound in each of time domains A1 to A5. [Diagram 5] 13 is a diagram illustrating an example of the outline of a graph showing the frequency dependence of the volume of sound generated in association with the driving of the driving mechanism 20. FIG. [Figure 6] 13 is a flowchart showing an example of a control method for controlling the driving of an optical element using a driving mechanism control unit 30. [Figure 7A] 13 is a graph showing an example of the relationship between the position of the optical element and the sound generated by driving the drive mechanism 20 when sound suppression control by the drive mechanism control unit 30 is not used. [Figure 7B] 13 is a graph showing an example of the relationship between the position of the optical element and the sound generated by driving the drive mechanism 20 when sound suppression control of the drive mechanism control unit 30 is used. [Figure 8A] 13 is a flowchart showing an example of an updating method for updating relationship information stored in the first storage unit 52 using the calibration unit 36. [Figure 8B] 8B is a flowchart illustrating an example of the process of step S202 in FIG. 8A. [Figure 8C] 8B is a flowchart illustrating another example of the process in step S202 in FIG. 8A. [Figure 9] 2 is a block diagram showing an example of the configuration of a processing unit 90 provided outside the imaging device 100. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0024] The present invention will be described below through embodiments of the invention, but the following embodiments do not limit the scope of the invention according to the claims. Furthermore, not all of the combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0025] 1 is a diagram showing an example of the configuration of an imaging device 100. The imaging device 100 is a device that allows a user to capture still images or moving images of a subject.

[0026] As an example, the imaging device 100 is a device including a camera built into a smartphone, a tablet, a laptop computer, a small personal computer, or the like. As another example, the imaging device 100 may be a device including a camera for capturing moving images, such as a digital camera, a web camera, or a video camera. The imaging device 100 includes an optical system 10, an imaging element 12, a driving mechanism 20, a magnetic sensor 22, a microphone 24, a driving mechanism control unit 30, an imaging control unit 40, a storage unit 50, a display unit 60, and an operation unit 70.

[0027] The optical system 10 is a compound lens system that forms an image of a subject on the image sensor 12. The optical system 10 includes at least one of a zoom lens and a focus lens. The optical system 10 is supported by the image capture device 100 via a support mechanism. The optical system 10 of this embodiment is magnetically driven by a drive mechanism 20, which will be described later. Therefore, in this embodiment, a magnet is provided in the support mechanism of the optical system 10 with respect to the image capture device 100.

[0028] The imaging element 12 captures an image (picture or video) of a subject formed on the imaging surface of the imaging element 12 via the optical system 10, and outputs the image or video data to the imaging control unit 40. In the following, a still image of a subject captured by the imaging element 12 may be referred to as an image or still image, and a moving image may be referred to as a video or moving image. The imaging element 12 may be configured with a CCD or CMOS.

[0029] The driving mechanism 20 drives the optical system 10 or the image sensor 12 relative to the image sensor 12 to change the position of the optical system 10 or the image sensor 12. This provides the imaging device 100 with a lens position control function for focus control, blur correction control, and the like for an image or video captured by the image sensor 12 via the optical system 10.

[0030] Here, in this specification, the optical system 10 and the image sensor 12 may be collectively referred to as the "optical element." When the imaging device 100 is provided with an image blur correction function or the like for an image or video captured by the optical element, the driving mechanism 20 may drive the image sensor 12 instead of or in addition to the optical system 10. For the sake of simplicity of explanation, the drawing shows an example in which the driving target of the driving mechanism 20 is the optical system 10, but the driving target of the driving mechanism 20 is not limited thereto, and this embodiment includes a case in which the driving mechanism 20 drives either the optical system 10 or the image sensor 12, or both.

[0031] The driving mechanism 20 of this embodiment varies the position and angle (hereinafter, the position and angle may be collectively referred to as "position") of the optical system 10 or the image sensor 12 by driving the optical system 10 or the image sensor 12. When a three-dimensional space is expressed as an XYZ space, the driving mechanism 20 may vary the position of the optical system 10 or the image sensor 12 in one direction in the XYZ space, or may vary the positions in multiple directions.

[0032] For example, the driving mechanism 20 drives the optical system 10 or the image sensor 12 along the optical axis direction of the lens of the optical system 10 to implement focusing control such as an autofocus function of the imaging device 100. That is, the driving mechanism 20 drives the optical element along the optical axis of the optical element. The optical axis of the lens means an axis connecting the center point of the lens and the focal position of the lens. In addition, the "direction along the optical axis direction of the lens" may mean, for example, a direction in which the angle between the X-axis and the Y-axis and the angle between the Z-axis and the X-axis are within a range of ±3 degrees or less with respect to the optical axis direction (the direction parallel to the optical axis direction is the X-axis direction). However, the "direction along the optical axis direction of the lens" may be determined to be a direction in which the angle between the X-axis and the Y-axis and the angle between the Z-axis and the X-axis are within a range of ±1 degree or less, or the angle between the X-axis and the Y-axis and the angle between the Z-axis and the X-axis are within a range of ±0.5 degrees or less, depending on a correction function to be implemented in the imaging device 100.

[0033] Alternatively, the driving mechanism 20 varies the position and angle of the optical system 10 or the image sensor 12 to implement a shake correction function of the imaging device 100. In order to quickly follow up on blurring caused by camera shake or the like, the driving mechanism 20 may drive the image sensor 12 when the image sensor 12 is lighter than the optical system 10, or may drive both the optical system 10 and the image sensor 12.

[0034] The driving mechanism 20 of this embodiment is an electromagnetic actuator that drives the optical element through electromagnetic interaction by varying the magnetic field around the optical element. The driving mechanism 20 includes a voice coil motor 200 and a motor driver 202. However, the driving mechanism 20 is not limited to an electromagnetic actuator, and may be a shape memory alloy (SMA) actuator, a piezoelectric actuator, or the like.

[0035] The magnetic sensor 22 detects the position of the optical system 10 or the imaging element 12, and outputs a detection signal indicating the position of the optical system 10 or the imaging element 12. The magnetic sensor 22 is a magnetic sensor using a magnetic sensor element such as a Hall element, a TMR element using a tunnel magnetoresistance effect, or a GMR element using giant magnetoresistance. The magnetic sensor 22 may include one or more magnetic sensor elements depending on the desired detection range and detection accuracy when detecting the position of the optical system 10 or the imaging element 12. For example, the magnetic sensor 22 may include multiple Hall elements. When the driving mechanism 20 is an electromagnetic actuator, precise position measurement can be performed by using the magnetic sensor 22.

[0036] When detecting the position using the magnetic sensor 22, the magnetic sensor 22 may be provided at a position where it is easy to detect the magnetic field that the driving mechanism 20 varies around the magnet of the optical element. As an example, the magnetic sensor 22 is provided on an axis passing through the geometric center of the coil winding in the voice coil motor 200. However, the magnetic sensor 22 may be provided anywhere in the imaging device 100 as long as it is possible to detect the position of the optical system 10 or the imaging element 12.

[0037] The imaging device 100 may include other sensors such as an inertial measurement unit (IMU) as a configuration for detecting the position of the optical element, instead of or in addition to the magnetic sensor 22. The detection signal may be a signal corresponding to position information of the optical system 10 or the imaging element 12 output by such a composite sensor.

[0038] The microphone 24 detects sound data corresponding to sounds generated in association with the driving of the drive mechanism 20. The microphone 24 outputs a current or voltage corresponding to the sound data to the drive mechanism control unit 30. The microphone 24 may also be a microphone used to record sound when the imaging device 100 captures moving images.

[0039] The drive mechanism control unit 30 outputs a control signal for controlling the supply of voltage, current, etc., supplied to the voice coil motor 200 so that the drive mechanism 20 drives the optical element. Specifically, the drive mechanism control unit 30 outputs a control signal for driving the optical element so as to move the optical element to a target position and suppress sound generated by driving the drive mechanism 20, based on a target position command signal from the imaging control unit 40 and a detection signal from the magnetic sensor 22.

[0040] The drive mechanism control unit 30 may control the optical element to move by the step width at each update period of the control signal, gradually moving it to the final target position. Therefore, the update period of the control signal indicates the period during which the target position indicated by the control signal is updated. In other words, the update period of the control signal indicates the period during which the target position indicated by the control signal is fixed to a predetermined value. The step width of the control signal is a fixed amount of movement (distance) by which the optical element moves in one operation in multiple steps in which the drive mechanism control unit 30 changes the position within the update period when driving the optical element from the current position to the final target position. A specific example of the update period and step width (update period 102 and step width 104) will be described later with reference to FIG. 3.

[0041] Here, the drive mechanism control unit 30 may be integrated on the same IC chip as the magnetic sensor 22, and the drive mechanism control unit 30 is an example of a "control device." That is, the imaging device 100 may include an IC chip, and the IC chip may include the magnetic sensor 22. The IC chip may also include the drive mechanism control unit 30. The drive mechanism control unit 30 includes a generation unit 32. The generation unit 32 generates a control signal for moving the optical element to a target position, and outputs the control signal to a motor driver 202. The motor driver 202 supplies a voltage or current corresponding to the control signal to the voice coil motor 200. The voice coil motor 200 is driven according to the voltage or current from the motor driver 202 to move the optical element.

[0042] In this embodiment, the generating unit 32 generates a control signal for moving the optical element to a target position while suppressing the sound generated by the driving of the driving mechanism 20. The generating unit 32 acquires a detection signal indicating the position of the optical element via the magnetic sensor 22. Furthermore, as described later with reference to FIG. 2A, the generating unit 32 generates a control signal for moving the optical element to a target position while suppressing the sound generated by the driving of the driving mechanism 20, based on position information of the optical element read from the target position signal and the detection signal from the magnetic sensor 22, and relationship information indicating the relationship between an index according to the volume of the sound generated by the driving of the driving mechanism 20 and the position of the optical element.

[0043] In particular, the generator 32 performs PID (Proportional Integral Differential) control when moving the optical element to a target position, as described below with reference to the PID control unit 324 in Fig. 2A. Therefore, the generator 32 generates a control signal based on PID parameters having proportional, integral, and differential components for the deviation between the target position and the current position acquired from the detection signal. The generator 32 generates a control signal with these PID parameters corrected when suppressing the sound according to the position of the optical element.

[0044] Furthermore, the sound generated by the driving mechanism 20 may depend on the speed and acceleration at which the optical element moves. The generating unit 32 can generate a control signal for suppressing the sound generated by the driving mechanism 20 by suppressing the speed or acceleration at which the optical element moves.

[0045] The imaging control unit 40 outputs a target position signal indicating a target position of the optical element. The imaging control unit 40 sets a target position of the optical element based on at least one of a user's operation input from the operation unit 70, the contrast of an image or video captured by the imaging element, and phase difference data detected by an autofocus sensor provided together with the imaging element, and outputs the target position signal.

[0046] The storage unit 50 stores information for the drive mechanism control unit 30 and the imaging control unit 40 to control the position of the optical system 10 or the image sensor 12. The storage unit 50 may have a memory that stores the control information of the drive mechanism control unit 30 and a memory that stores the control information of the imaging control unit 40. The storage unit 50 may have a single memory that stores the control information of both the drive mechanism control unit 30 and the imaging control unit 40.

[0047] The display unit 60 displays to the user an image or video of a subject captured by the imaging device 100. Based on the image or video displayed on the display unit 60, the user can perform various operations using the operation unit 70 described below.

[0048] The operation unit 70 is an interface for a user of the imaging device 100 to operate the imaging device 100. By using the operation unit 70, the user can execute various operations on the image or video confirmed through the display unit 60. Through the operation unit 70, the user can, for example, select a focus target, switch between a video shooting mode and a still image shooting mode, and end the timing of starting and ending storage of a video in the storage unit 50.

[0049] Here, the driving mechanism control unit 30 has an operation mode of a correction mode and a non-correction mode. The "correction mode" is a mode in which control is performed based on a control signal corrected to suppress sound depending on the position of the optical system 10 or the image sensor 12 when driving the driving mechanism 20 to a target position. On the other hand, the "non-correction mode" is a mode in which correction of the control signal to suppress sound depending on the position is not performed when driving the driving mechanism 20 to a target position.

[0050] As described below, the drive mechanism control unit 30 can switch the operation mode between the correction mode and the non-correction mode. Furthermore, the user can switch the operation mode of the drive mechanism control unit 30 between the correction mode and the non-correction mode via the operation unit 70.

[0051] When a user takes a still image, or when the position of a subject to be focused on during video shooting is not changed much and the driving mechanism 20 is driven only with power equal to or lower than a predetermined threshold, sound may not be recorded in the shooting data even if it is generated. In such a case, the driving mechanism control unit 30 may operate in a non-correction mode that does not correct the control signal for sound suppression in this embodiment.

[0052] In the correction mode for suppressing sound, the moving speed of the optical element is reduced in positions where loud sounds may be generated. Therefore, in cases where the above-mentioned sounds are not a problem, the user can consciously switch between the correction mode and the non-correction mode via the operation unit 70.

[0053] Specifically, the user of the imaging device 100 transmits a command to switch between the correction mode and the non-correction mode to the drive mechanism control unit 30 via the operation unit 70. In this embodiment, the imaging control unit 40 receives a command to switch between the correction mode and the non-correction mode from the user via the operation unit 70. The imaging control unit 40 transmits a command to switch between the correction mode and the non-correction mode to the drive mechanism control unit 30. Upon receiving the command to switch between the correction mode and the non-correction mode, the drive mechanism control unit 30 executes switching between the correction mode and the non-correction mode in accordance with the command. However, the switching between the correction mode and the non-correction mode may be input directly from the operation unit 70 to the drive mechanism control unit 30.

[0054] Next, an example in which the drive mechanism control unit 30 switches between the correction mode and the non-correction mode will be described. A user of the imaging device 100 switches between the moving image imaging mode and the still image imaging mode for an image to be captured via the operation unit 70. In this case, the drive mechanism control unit 30 receives a notification from the imaging control unit 40 indicating that the moving image imaging mode and the still image imaging mode have been switched, and switches between the correction mode and the non-correction mode in response to the notification, so that the drive mechanism control unit 30 may operate in the correction mode during the moving image imaging mode and operate in the non-correction mode during the still image imaging mode.

[0055] As another example, when the position of the focus target does not change for a long time and the imaging device 100 is fixed to a fixture such as a tripod, and therefore no blurring or the like is detected, the drive mechanism control unit 30 may operate in the non-correction mode. Then, when the imaging control unit 40 detects the movement of the focus target and image blurring, the drive mechanism control unit 30 may switch the operation mode to operate in the correction mode.

[0056] As yet another example, if the imaging device 100 has a switch for turning on and off an OIS (optical image stabilization) mode, it is expected that high-speed position control of optical elements will be performed in the OIS. Therefore, the drive mechanism control unit 30 may switch from the non-correction mode to the correction mode in response to the imaging control unit 40 turning on the OIS mode. The drive mechanism control unit 30 may switch from the correction mode to the non-correction mode in response to the imaging control unit 40 turning off the OIS mode, or detecting that the imaging device 100 has been installed on a tripod or the like.

[0057] In the imaging device 100, the display unit 60 and the operation unit 70 may be provided integrally as a touch screen. However, the operation unit 70 may be provided as an element separate from the display unit 60, like the operation buttons of a camera.

[0058] Next, we will explain the configuration of the drive mechanism 20. The voice coil motor 200 varies the magnetic field around a magnet provided together with the optical element by electromagnetic induction, and drives the optical system 10 or the image sensor 12 by the electromagnetic force generated in response to the variation in the magnetic field.

[0059] The driving force of the voice coil motor 200 is proportional to the magnitude of the current flowing through the coil of the voice coil motor 200. Therefore, the sound generated by the driving mechanism 20 in driving the optical element tends to become louder as the driving force increases.

[0060] Furthermore, the sound generated by the driving mechanism 20 when driving the optical element tends to become louder as the rate of change of the current flowing through the voice coil motor 200 of the voice coil motor 200 becomes steeper. If the rate of change of the current is made steep, for example, a sudden change in current may generate a force similar to an impact force on at least some of the components in the driving mechanism 20, particularly the components of the voice coil motor 200. Such a force may generate stress in the components or structure of the driving mechanism 20, causing vibrations within the driving mechanism 20. Therefore, the vibrations within the driving mechanism 20 may increase the sound generated as the driving mechanism 20 is driven.

[0061] In particular, when vibration occurs in the above example, the frequency of the vibration may be close to a resonant frequency in a component or structure of the drive mechanism 20. When vibration with a frequency close to a resonant frequency occurs, the vibration within the drive mechanism 20 may increase the sound generated when the drive mechanism 20 is driven.

[0062] As another example, if the rate of change of the current is made steep, the speed or motion of the optical element may change due to the sudden current flow, causing fluctuations in the contact or frictional force of at least some of the components in the drive mechanism 20, particularly the rotating body of the voice coil motor 200. Such fluctuations in contact or frictional force may increase the sound generated when the drive mechanism 20 is driven.

[0063] The generating unit 32 can generate a control signal that suppresses at least one of the voltage, the rate of change of the current, and the magnitude of the current supplied to the voice coil motor 200 in order to suppress noise generated by driving the driving mechanism 20.

[0064] The motor driver 202 adjusts at least one of the voltage, the rate of change of the current, and the magnitude of the current supplied to the voice coil motor 200 based on the control signal output by the drive mechanism control unit 30, thereby adjusting the magnetic field fluctuated by the voice coil motor 200. In this way, the motor driver 202 applies a driving force to the optical element. Therefore, the drive mechanism 20 drives the optical element with the driving force from the voice coil motor 200 based on the control signal.

[0065] In the imaging device 100 of this embodiment, when the drive mechanism control unit 30 is integrated on the same IC chip as the magnetic sensor 22, the signal processing in the drive mechanism control unit 30 may be performed by digital processing. In such a case, the drive mechanism control unit 30 may include an ADC (Analog to Digital Converter) for converting the detection signal from the magnetic sensor 22 into a digital signal. On the other hand, the drive mechanism 20 may include a DAC (Digital to Analog Converter) for converting the control signal provided from the drive mechanism control unit 30 into an analog signal and providing it to the motor driver 202.

[0066] Thus, each component of the image capture device 100 may include an ADC or a DAC to appropriately digitally or analogically process the signal, and such an ADC or DAC is omitted from the drawings for the sake of simplicity.

[0067] Here, when the driving mechanism 20 drives the optical element, a sound associated with the driving may be generated in at least one of the optical element and its support mechanism and the driving mechanism 20. When a user captures a video of a subject using the imaging device 100, the sound of the subject during the capture is recorded along with the video. To provide a good user experience for a user watching the captured video, it is preferable that the sound is small compared to the recorded sound.

[0068] The sound caused by the driving of the optical element by the driving mechanism 20 is generated due to the influence of frictional force while the optical element moves. The value of the frictional force while the optical element moves may vary depending on the position of the optical system 10 or the image sensor 12. Among these, the value of the kinetic frictional force may vary, for example, due to the amount of grease applied to the optical element or the support mechanism varying, and the kinetic friction coefficient of the optical element may vary depending on the position within the driving range of the optical element.

[0069] Therefore, the sound generated by the driving mechanism 20 driving the optical element is a sound according to the position of the optical system 10 or the image sensor 12. Such a sound becomes louder particularly when the speed of the optical system 10 or the image sensor 12 is high. In the imaging device 100, if the dependency of the sound on the position of the optical element is not evaluated and driving control is performed to uniformly reduce the sound, this may limit the driving speed of the entire driving control by the driving mechanism 20.

[0070] The generating unit 32 may generate a control signal for moving the optical element to a target position while suppressing the sound according to the position of the optical element, based on the relationship between the position of the optical element read from the detection signal and the sound accompanying the drive according to the position acquired from the microphone 24. The internal configuration and operation of the generating unit 32 will be described in detail below with reference to Fig. 2A.

[0071] 2A is an example of a block diagram showing the configuration of the generation unit 32 and the storage unit 50. The generation unit 32 includes a correction coefficient output unit 322 and a PID control unit 324. The storage unit 50 includes a first storage unit 52 and a second storage unit 54.

[0072] The generation unit 32 generates a control signal based on a detection signal indicating the position of the optical element, a correction coefficient corresponding to the loudness of the sound generated by the drive mechanism, and relationship information indicating the relationship between the position of the optical element read from the sound data corresponding to the position of the optical element and the optimal correction coefficient. The relationship information is information indicating the correction coefficient corresponding to the position of the optical element for correcting the control signal according to the loudness of the sound generated by the drive mechanism 20 being driven, as an index corresponding to the loudness of the sound generated by the drive mechanism 20 being driven.

[0073] The correction coefficient output unit 322 calculates a correction coefficient for the PID parameter and outputs the calculated correction coefficient. Specifically, the correction coefficient output unit 322 of this embodiment calculates a correction coefficient based on the current position of the optical element read from the detection signal and the related information read from the first storage unit 52, and outputs the calculated correction coefficient to the PID control unit 324.

[0074] In calculating the correction coefficient, the correction coefficient output unit 322 of this embodiment detects the current position of the optical element based on a detection signal based on the position detected by the magnetic sensor 22. However, the correction coefficient output unit 322 may specify the position of the optical element based on a target position indicated by a target position signal. Another advantage of position detection from a target position signal is that the target position signal has high noise resistance.

[0075] That is, when the generating unit 32 specifies the correction coefficient, the generating unit 32 may specify the position of the optical element based on at least one of the detection signal and the target position signal. In this case, the generating unit 32 can specify the correction coefficient corresponding to the specified position of the optical element by referring to the relationship information stored in the first storage unit 52. Therefore, the generating unit 32 may generate a control signal based on the correction coefficient according to the position of the optical element, the target position signal indicating the target position, and the detection signal.

[0076] The PID control unit 324 performs a calculation to calculate a reference PID parameter based on the deviation between the current position and the target position, and stores the result in the second storage unit 54. The PID control unit 324 calculates a PID parameter that reflects a correction using a correction coefficient for the calculated reference PID parameter.

[0077] The reference PID parameters are PID parameters when no correction using the correction coefficients is performed in the PID control unit 324. In the non-correction mode, the imaging device 100 can generate a control signal using the reference PID parameters.

[0078] Specifically, the PID control unit 324 calculates PID parameters for each of the proportional component, the integral component, and the derivative component based on the deviation between the current position of the optical element obtained from the detection signal and the target position obtained from the target position signal. The PID control unit 324 further adds or subtracts the proportional component, the integral component, and the derivative component using an adder.

[0079] The correction coefficient calculated by the correction coefficient output unit 322 may be a coefficient that corrects at least one of the proportional component, the integral component, and the differential component before being added or subtracted by the adder, or may be a coefficient that corrects the addition / subtraction results of the proportional component, the integral component, and the differential component. Therefore, the generation unit 32 can correct the PID parameters by performing arithmetic operations on at least one of the proportional component, the differential component, and the integral component based on the deviation between the target position signal and the detection signal to apply a correction coefficient according to the position of the optical element.

[0080] The PID control unit 324 further outputs a control signal for controlling the movement of the optical element so that the position of the optical element reaches the target position read from the target position signal from the current position acquired from the detection signal. The generation unit 32 may generate a control signal based on the PID parameters corrected in this way, and the drive mechanism control unit 30 may output the generated control signal.

[0081] In this way, the generation unit 32 can generate a control signal for PID control of the drive mechanism 20 based on the correction coefficient according to the position of the optical element, the target position signal, and the detection signal. Therefore, the generation unit 32 generates a control signal based on the correction coefficient according to the position of the optical element, the target position signal indicating the target position, and the detection signal.

[0082] There are several means for implementing the control by the drive mechanism control unit 30 to suppress the sound caused by the drive of the drive mechanism 20 in accordance with the position of the optical element. Some of these means will be exemplified below.

[0083] For example, the generation unit 32 may adjust the control signal to reduce the deviation between the current position and the target position input for correcting the PID parameters, that is, to set a provisional target position that brings the target position closer to the current position, in order to suppress the sound corresponding to the position of the optical element when the drive mechanism 20 drives the optical element. For example, the generation unit 32 may implement this by adjusting the value of the control signal to set a provisional target position so as to reduce the deviation between the target position and the current position.

[0084] In this way, the generator 32 may set a provisional target position that reduces the deviation between the position of the optical element and the target position in the control signal, and gradually control the provisional target position to approach the original target position in the target position signal. By setting the deviation between the current position and the provisional target position to be smaller than the deviation between the current position and the original target position, the speed of the optical system 10 or the image sensor 12 is reduced, and as a result, the sound caused by the driving mechanism 20 is reduced.

[0085] As another example, the drive mechanism control unit 30 may use the control signal to limit an amount of operation, such as a speed or acceleration, that the drive mechanism 20 uses to operate the optical element to a target position. For example, the drive mechanism control unit 30 may set a predetermined threshold value for the amount of operation depending on the position, and limit the amount of operation to be equal to or less than the threshold value. Alternatively, the drive mechanism control unit 30 may limit the amount of operation to a constant value within a predetermined driving range of the drive mechanism 20.

[0086] In this way, the generation unit 32 may generate a control signal corrected by a correction coefficient so as to adjust the gain of the driving band of the driving mechanism 20. In particular, the generation unit 32 may generate a control signal for correcting the gain of the driving band of the driving mechanism 20 by arithmetic operations using a correction coefficient according to the position of the optical element.

[0087] As yet another example, the generation unit 32 can reduce the sound generated by driving the drive mechanism 20 by changing the frequency at which the value indicated by the control signal is changed depending on the position of the optical element. Specifically, the drive mechanism control unit 30 reduces the update frequency of the control signal to be output in a range in which the sound generated by driving the drive mechanism 20 becomes louder. Since the control signal is not updated, the control signal shows the same value, the current supplied to the voice coil motor 200 becomes constant, and the slope of the current becomes smaller. As a result, the sound generated by driving the drive mechanism 20 can be suppressed in a range in which the update frequency of the control signal is reduced.

[0088] As already described, the imaging device 100 of this embodiment is provided with an ADC and a DAC as necessary. In particular, when a digital signal is input from the drive mechanism control unit 30 to the drive mechanism 20 and a signal converted by the DAC is input to the motor driver 202, the control of reducing the update frequency of the control signal can also be achieved by reducing the update frequency of this DAC.

[0089] That is, in order to suppress the sound generated by driving the drive mechanism 20, the drive mechanism control unit 30 may control the DAC to lengthen the update period 102 of the DAC that controls the input to the drive mechanism 20 within a range in which the sound generated by driving the drive mechanism 20 becomes large. This allows the drive mechanism control unit 30 to reduce the frequency at which the magnitude of the current supplied to the voice coil motor 200 is updated and the fluctuations in the drive force. As a result, the drive mechanism control unit 30 can suppress the sound generated by driving the drive mechanism 20.

[0090] As yet another example, the motor driver 202 may adjust the power supply or the like to lower the level of the power supply voltage supplied to the drive mechanism 20 in a range in which the sound generated by the drive mechanism 20 becomes louder according to the position of the optical element, so as to suppress the sound generated by the drive mechanism 20 being driven. For example, the drive mechanism control unit 30 may reduce the level of the voltage supplied to the motor driver 202 via a level shifter in a range in which the sound generated by the drive mechanism 20 becomes louder according to the position of the optical element. Instead of or in addition to controlling the power supply voltage, the motor driver 202 may adjust the absolute value of the current supplied to the voice coil motor 200, the magnitude of the current gradient, or the current acceleration to be smaller. In this way, the drive mechanism control unit 30 can also control the absolute value of the current supplied to the voice coil motor 200 and the magnitude of the rate of change of the current by the control signal it outputs.

[0091] Furthermore, the drive mechanism control unit 30 may use a control signal to reduce a duty ratio (corresponding to the density of a pulse wave supplied by PWM control) of the current supplied from the motor driver 202 to the voice coil motor 200 by PWM (Pulse Width Modulation) control or the like in order to suppress sound generated by driving the drive mechanism 20. In this way, the drive mechanism control unit 30 can control the drive mechanism 20 to reduce the density of the pulse wave supplied to the voice coil motor 200 in a range in which sound generated by driving the drive mechanism 20 becomes large, thereby reducing the power supplied to the voice coil motor 200. This allows the drive mechanism control unit 30 to suppress sound generated by driving the drive mechanism 20.

[0092] As yet another example, the drive mechanism 20 may include, as the motor drivers 202, a plurality of motor drivers 202 each having a different power output to the voice coil motor 200. In order to suppress sound generated by driving the drive mechanism 20, the drive mechanism control unit 30 selects, from the plurality of motor drivers 202, a motor driver 202 capable of supplying to the voice coil motor 200 a power capable of suppressing sound generated by driving the drive mechanism 20 to a predetermined level or less in accordance with the position of the optical element.

[0093] For example, the storage unit 50 stores a predetermined correspondence table that assigns a motor driver 202 that supplies voltage, current, or power to the voice coil motor 200 for each range of voltage, current, or power to be supplied to the voice coil motor 200. The drive mechanism control unit 30 selects a motor driver 202 that supplies voltage, current, or power from among the multiple motor drivers 202 based on the desired voltage, current, or power and the correspondence table, and outputs a control signal to the selected motor driver 202. The selected motor driver 202 supplies voltage, current, or power to the voice coil motor 200 based on the control signal. This allows the drive mechanism control unit 30 to suppress sound generated by driving the drive mechanism 20 according to the position of the optical element.

[0094] The above have given several examples of control for reducing the sound generated by driving the drive mechanism 20, which is realized by the drive mechanism control unit 30, the imaging control unit 40, etc., depending on the position of the optical element. Unlike cases where the drive force is simply controlled without the aim of suppressing the sound generated by driving, these controls may include control of the speed or acceleration of the optical system 10 or the imaging element 12, the slope (current change rate) or current acceleration of the current flowing through the voice coil motor 200, etc., depending on the position of the optical system 10 or the imaging element 12.

[0095] By performing these controls, sound that occurs in association with the driving of the driving mechanism 20 and corresponds to the position of the optical system 10 or the image sensor 12 is suppressed, and the reduction in speed of the optical system 10 or the image sensor 12 is smaller than when control in accordance with the relative positions is not performed. Therefore, in control that accompanies the driving of the driving mechanism 20, such as image stabilization control and focus control of the imaging device 100, both high speed and quiet operation are achieved.

[0096] As already explained, the first storage unit 52 stores the related information. The IC chip having the drive mechanism control unit 30 may have the first storage unit 52. As will be described later with reference to Fig. 5, the first storage unit 52 may store data on the correspondence between the loudness of the sound generated when the drive mechanism 20 drives the optical element and a correction coefficient defined for the loudness of the generated sound. The second storage unit 54 stores the reference PID parameters.

[0097] Fig. 2B is an example of a block diagram showing the configuration of the generating unit 32, the storage unit 50, and the calibration unit 36. Compared to the embodiment of Fig. 2A, in the embodiment of Fig. 2B, the drive mechanism control unit 30 includes a calibration unit 36. Therefore, hereinafter, the calibration unit 36, which is a difference from Fig. 2A, will be described in detail, and the description already given in Fig. 2A will be omitted.

[0098] In the present embodiment, the calibration unit 36 ​​is provided in the drive mechanism control unit 30, separately from the generation unit 32. However, the calibration unit 36 ​​may be provided in the generation unit 32.

[0099] Here, for example, due to deterioration of the support mechanism of the optical element over time, sound may increase at a specific position of the optical element when the drive mechanism 20 is driven. In such a case, the calibration unit 36 ​​is provided to calibrate the relationship information stored in the first storage unit 52. The calibration unit 36 ​​generates relationship information based on sound information indicating the volume of sound corresponding to the position of the optical element generated by driving the drive mechanism 20 according to predetermined drive conditions and correction coefficient information indicating the relationship between the volume of the sound and the correction coefficient, and stores the relationship information in the first storage unit 52. By providing the calibration unit 36, even if the relationship information has changed since the time of shipment, the relationship information stored in the first storage unit 52 can follow the change, and the generation unit 32 can generate a control signal using the relationship information reflecting the change.

[0100] In cases where the impact of increased sound due to deterioration over time during operation is small, and where relationship information measured in advance before shipping and stored in first storage unit 52 is used, calibration unit 36 ​​may be omitted as in the embodiment of Fig. 2A. In cases where calibration unit 36 ​​is omitted and microphone 24 is a microphone separate from a microphone for recording audio data in video data during video shooting, microphone 24 may be omitted in imaging device 100.

[0101] The predetermined driving conditions of the driving mechanism 20 include a step width indicating a distance by which the optical element is moved according to a target position, and an update cycle of the target position. Furthermore, the driving conditions of the optical element may include an ambient environmental condition in which the imaging device 100 exists. The environmental condition may include temperature, humidity, altitude, or the like. The predetermined driving conditions are, for example, driving conditions indicating a distance (step width) that the focus lens moves in one drive and a drive cycle (update cycle) of the focus lens in contrast autofocus (AF) that adjusts the focus position based on the brightness difference (contrast) of an image or video while moving the focus lens.

[0102] The calibration unit 36 ​​detects the position of the optical element based on at least one of the detection signal and the target position signal. Furthermore, the microphone 24 detects sound generated by the driving mechanism 20 being driven, and transmits the sound data to the calibration unit 36. Therefore, the calibration unit 36 ​​can generate sound data according to the position from the sound data collected by the microphone 24 by collating the position data with the sound data.

[0103] Furthermore, the calibration unit 36 ​​divides the sound data collected by the microphone 24 into sound data for each time domain based on, for example, the update period or the step width. A specific example of this will be described with reference to FIG.

[0104] FIG. 3 is an example of a graph showing the relationship between time and the position of the optical element, and the relationship between time and the volume of sound. The calibration unit 36 ​​divides the period during which sound data was collected into time domain units of the width of the update period according to the number of steps, in accordance with the update period 102 of the target position indicated by the control signal or the period during which the target position indicated by the control signal increases or decreases by the step width 104. For illustrative purposes, FIG. 3 shows an example in which the period is divided into time domains A1 to A8. The number of time domains shown in FIG. 3 is an example for illustrative purposes, and in the actual drive control of the optical element by the drive mechanism 20, the number of time domains may be less or more.

[0105] When the control signal fluctuates by step width 104 at the start points of the time regions A1 to A8, the position of the optical element fluctuates during each of the time regions A1 to A8. Therefore, the calibration section 36 may divide the time regions A1 to A8 based on the update period, or may divide the time regions A1 to A8 based on the timing at which the position of the optical element changes by the step width 104.

[0106] Furthermore, the calibration unit 36 ​​acquires data on the volume of sound generated in each time domain in association with the driving of the driving mechanism 20. Here, the sound generated in each time domain in association with the driving of the driving mechanism 20 includes a sound that depends on the magnitude of the gradient of the current flowing into the voice coil motor 200 of the driving mechanism 20, and a sound that depends greatly on the speed of the optical element.

[0107] At the end of each time region, the optical element is in a stationary state for a predetermined period of time. Therefore, when the driving mechanism 20 drives the optical element, the stationary optical element is driven for a predetermined period of time from the start of each time region having a width of each update period.

[0108] The calibration unit 36 ​​may perform a process of generating or updating the related information stored in the first memory unit 52 for each step width 104 or update period 102 by adjusting a correction coefficient for suppressing the sound so that the rate of change of the current supplied to the drive mechanism 20 becomes small when the sound generated before and after the optical element starts to drive is equal to or greater than a predetermined volume.

[0109] Here, "before and after the optical element starts to drive" refers to the period from when the current for driving the optical element starts to flow through the driving mechanism 20 until the optical element starts to drive. In other words, it is a predetermined period including the time when the optical element in a stationary state starts to drive, and refers to a predetermined period from the start of each time domain.

[0110] During this period, the friction coefficient of the friction generated by the friction of the optical element, etc. is mainly the static friction coefficient, and the influence of the dynamic friction coefficient is small. In this way, when moving the optical element from a stationary state, the sound depends greatly on the magnitude of the rate of change of the current flowing into the voice coil motor 200 to move the optical element against the static friction force. Also, one of the main causes of the sound in this case is the sound caused by the coil whine phenomenon that occurs in response to the current flowing into the inductor of the voice coil motor 200.

[0111] When the sound generated before and after the optical element starts to drive is equal to or greater than a predetermined volume, the calibration unit 36 ​​refers to correction coefficient information, which is stored in advance in the memory unit 50, that indicates the relationship between the sound volume and the correction coefficient when the sound generated by the drive mechanism 20 being driven depends on the static friction force of the optical element, and determines an optimal correction coefficient that reduces the rate of change of the current supplied to the drive mechanism 20 to suppress the sound.

[0112] On the other hand, after this period has passed, that is, "while the optical element is being driven," the proportion of sound generated by the driving mechanism 20 based on the kinetic frictional force of the optical element increases. The volume of sound generated based on the kinetic frictional force of the optical element largely depends on the speed of the optical element. For a given position, the static frictional force is greater than the kinetic frictional force. However, when the moving speed is high, or when the amount of grease for reducing friction at a specific position in the moving section is small, the sound generated while the optical element is being driven may be greater than the sound generated before and after the optical element starts to drive.

[0113] The calibration unit 36 ​​may execute a process of generating or updating related information for each step width 104 or update period 102 by adjusting a correction coefficient for suppressing the sound so that the rate or magnitude of change in the drive speed of the drive mechanism 20 is suppressed when the sound generated while the optical element is being driven by the drive mechanism 20 is equal to or greater than a predetermined volume.

[0114] When the sound generated while the optical element is driven by the drive mechanism 20 is at a predetermined volume or more, the calibration unit 36 ​​refers to correction coefficient information, which is stored in advance in the storage unit 50, indicating the relationship between the sound volume generated by the drive mechanism 20 being driven and the correction coefficient when the sound is dependent on the kinetic friction force of the optical element, and determines an optimal correction coefficient for suppressing the sound by reducing the rate of change or volume of the drive speed of the drive mechanism 20. The correction coefficient information is information that is stored in the storage unit 50, for example, by actually measuring the volume of the sound generated by the drive according to the position of the optical element while changing the correction coefficient, and deriving the correction coefficient dependent on the static friction force of the optical element and the correction coefficient dependent on the kinetic friction force of the optical element that can minimize the sound by experiment.

[0115] Furthermore, the calibration unit 36 ​​stores relationship information in the storage unit 50 for each of the cases where the sound generated by the driving of the driving mechanism 20 depends on the magnitude of the rate of change of the current and where it depends on the speed of the optical element. In this way, the calibration unit 36 ​​updates the relationship information stored in the storage unit 50.

[0116] Furthermore, when the effect of kinetic friction is large on the sound generated by driving the drive mechanism 20, the frequency of the sound is significantly affected by the frequency band below the drive band of the drive mechanism 20. As already mentioned, the variation in the kinetic friction of the optical element can be caused by manufacturing errors such as the amount of grease applied to the optical element or the support mechanism.

[0117] The sound generated by the coil whine phenomenon is a sound generated in a relatively high frequency band compared to the drive frequency band. Therefore, the calibration unit 36 ​​analyzes the frequency components of the sound generated by the drive mechanism 20, and, for example, sets a frequency threshold, separates the sound into high-frequency sounds having frequencies equal to or higher than the threshold and low-frequency sounds having frequencies lower than the threshold, and generates relational information for suppressing the sound for each frequency component. As will be described later with reference to FIG. 5, the frequency threshold is set as a threshold higher than the peak in the drive band of the drive mechanism 20 and lower than the peak due to the coil whine phenomenon. The frequency threshold may be, for example, 200 Hz.

[0118] In this way, as a first method for generating relationship information, the calibration unit 36 ​​can generate relationship information by dividing the sound generated in each time domain in association with the driving of the driving mechanism 20 into time components before and after the optical element starts to drive and while the optical element is driving. As a second method for generating relationship information, the calibration unit 36 ​​can generate relationship information by dividing the sound generated in each time domain in association with the driving of the driving mechanism 20 into frequency components equal to or higher than a threshold and frequency components below a threshold.

[0119] FIG. 4 is a diagram showing an example of the time dependency of the loudness and position of a sound in each of the time domains A1 to A5.

[0120] The calibration unit 36 ​​controls the volume of the sound in each of the time domains A1 to A5 so that it is less than the threshold value TH. In the sound generated by the driving of the driving mechanism 20, the first peak in each of the time domains A1 to A5 is the sound generated before and after the optical element starts to drive. On the other hand, in the sound generated by the driving of the driving mechanism 20, the peaks other than the first peak in each of the time domains A1 to A5 are the sound generated while the optical element is driving.

[0121] In the figure, an example is shown in which the first peak is equal to or greater than the threshold value TH in time domains A1 to A4, whereas in the example in the figure, peaks other than the first peak are equal to or greater than the threshold value TH in time domains A1 to A2 and A5.

[0122] Therefore, the calibration unit 36 ​​generates relationship information for controlling the magnitude of the rate of change of the current so that the sound generated before and after the optical element starts to drive in the time domains A1 to A4 is less than the threshold value TH. On the other hand, the calibration unit 36 ​​generates relationship information for controlling the speed of the optical element so that the sound generated while the optical element is driving in the time domains A1 to A2 and A5 is less than the threshold value TH.

[0123] The calibration unit 36 ​​does not generate relationship information for controlling the speed of the optical element in the time domains A3 and A4, and does not generate relationship information for controlling the magnitude of the rate of change of the current and the speed of the optical element in the time domain A5.

[0124] Here, the calibration unit 36 ​​may generate the relationship information based on, for example, the maximum value of the sound peak so that the sound generated by driving the drive mechanism 20 is less than the threshold value TH. Alternatively, the calibration unit 36 ​​may generate the relationship information based on the area of ​​the portion enclosed between the curved line of the sound peak and the horizontal line of the threshold value so that the sound generated by driving the drive mechanism 20 is less than the threshold value TH.

[0125] The calibration unit 36 ​​can read the position of the optical element from the magnetic sensor 22 or the target position signal. Note that the position of the optical element varies by approximately the step width 104 during the time domains A1 to A5. Therefore, in the position information read from the magnetic sensor 22 or the target position signal, the time domains A1 to A5 and the position correspond to each other with a tolerance of approximately the fluctuation width of the step width 104.

[0126] FIG. 5 is a diagram illustrating an example of the outline of a graph showing the frequency dependency of the volume of sound generated in association with the driving of the driving mechanism 20. In FIG.

[0127] The calibration unit 36 ​​divides the sounds in each time domain into main sources of generation by performing a Fourier transform, such as a fast Fourier transform (FFT), which converts time and frequency, on the sound data in each time domain A1 to A5 collected by the magnetic sensor 22. That is, the calibration unit 36 ​​extracts sounds that are generated depending on the magnitude of the rate of change of the current of 200 Hz or more and sounds that are generated depending on the speed of the optical element below 200 Hz.

[0128] In this embodiment, based on experimental data, 200 Hz is set as the threshold for distinguishing between the main causes of sound. However, based on requirements such as the design of the imaging device 100, the threshold may be set to 150 Hz, 250 Hz, or 300 Hz instead of 200 Hz.

[0129] The example shown in the figure is an outline of peaks 112 and 114 of sound data acquired in a time domain determined based on the update period or step width. Peak 114 is a sound component higher than 200 Hz among frequency components of sound generated in association with driving of drive mechanism 20. Peak 114 is a peak related to the static friction coefficient of each element when drive mechanism 20 drives the optical element. In other words, peak 114 corresponds to the first peak in the diagram showing the sound volume in FIG. 4. Peak 114 is a peak associated with the initial movement of the optical element from a stationary state, and therefore its peak width is likely to be narrower than peak 112.

[0130] On the other hand, peak 112 is a sound component lower than 200 Hz among the frequency components of the sound generated by driving drive mechanism 20. Peak 114 is a peak related to the dynamic friction coefficient of each element when drive mechanism 20 drives the optical element. In other words, peak 114 corresponds to a peak other than the first peak in the diagram showing the sound volume in FIG. 4. The frequency band in which peak 114 appears is a frequency band below the drive band of drive mechanism 20.

[0131] Therefore, the calibration unit 36 ​​identifies the frequency components of the sound generated in association with the driving of the driving mechanism 20 based on the sound information, and when the frequency components of the sound whose loudness is equal to or greater than a predetermined loudness include frequency components in the first frequency band, adjusts the correction coefficient so as to suppress the rate of change in the driving speed or the magnitude of the driving mechanism 20, thereby executing a process of generating or updating the relationship information for each step width 104 or update period 102. Here, the "first frequency" band is the band of the sound generated while the optical element is being driven, and is a frequency band equal to or less than the driving band of the driving mechanism 20.

[0132] Furthermore, when a frequency component in the second frequency band is included, the calibration unit 36 ​​executes a process of generating or updating the relationship information for each step width 104 or update period 102 by adjusting the correction coefficient so that the rate of change of the current supplied to the drive mechanism 20 becomes small. Here, the second frequency band is a frequency band higher than the drive band of the drive mechanism 20. As described above, the calibration unit 36 ​​can generate the relationship information.

[0133] 6 is a flowchart showing an example of a control method for controlling the driving of the optical element using the drive mechanism control unit 30. The control method includes steps S100 to S106.

[0134] The magnetic sensor 22 detects the position of the optical system 10 or the imaging element 12 and outputs a detection signal according to the position. The imaging control unit 40 outputs a target position signal for moving the optical element so that the position of the optical system 10 or the imaging element 12 reaches the target position.

[0135] The correction coefficient output unit 322 acquires the position of the optical element based on at least one of the detection signal and the target position signal, and the PID control unit 324 acquires the current position of the optical element from the detection signal (step S100).

[0136] Next, the correction coefficient output unit 322 calculates a correction coefficient based on the position information of the optical element and the relationship information stored in the first storage unit 52 (step S102), and outputs it to the PID control unit 324. Next, the PID control unit 324 calculates PID parameters based on the position information of the optical element acquired from the detection signal, the target position information acquired from the target position signal, and the correction coefficient (step S104).

[0137] Next, the PID control unit 324 outputs a control signal using the calculated PID parameters, and the drive mechanism control unit 30 controls the position of the optical system 10 or the image sensor 12, i.e., the position of the optical element, based on the control signal (step S106). In this way, the drive mechanism control unit 30 controls the position of the optical element.

[0138] Fig. 7A is a graph showing an example of the relationship between the position of the optical element and the sound generated by driving the drive mechanism 20 when the sound suppression control of the drive mechanism control unit 30 is not used. Meanwhile, Fig. 7B is a graph showing an example of the relationship between the position of the optical element and the sound generated by driving the drive mechanism 20 when the sound suppression control of the drive mechanism control unit 30 is used. Figs. 7A and 7B are graphs showing an example of the outline, and the horizontal and vertical axes of these graphs are shown in arbitrary units (au).

[0139] In Fig. 7A, curve 80 is a curve showing the relationship between the position of the optical element and the sound generated by driving drive mechanism 20. On the other hand, in Fig. 7B, curve 82 is a curve showing the relationship between the position of the optical element and the sound generated by driving drive mechanism 20, and curve 80 is also shown by a dashed line in the figure.

[0140] In the figure, curve 82 indicates a sound level equal to or lower than that of curve 80 over all positions. Since the sound is reduced in curve 82, the curve is substantially flat over all positions. As an example, in imaging device 100, drive mechanism control unit 30 controls the sound generated by driving drive mechanism 20 so that the absolute value of the sound at any frequency is equal to or lower than a predetermined threshold value over all positions of the optical element.

[0141] 8A is a flowchart showing an example of an updating method for updating the relationship information stored in the first storage unit 52, using the calibration unit 36. The updating method includes steps S200 to S206.

[0142] In this updating method, a generating method is shown in which the calibration unit 36 ​​is used to generate relationship information indicating the relationship between the position of the optical element and a correction coefficient of a control signal corresponding to the volume of sound generated with the driving of the driving mechanism 20. The relationship information is stored in the storage unit 50, and is referred to by a control device that generates a control signal for controlling the driving mechanism 20 to move the optical element to a target position while suppressing sound generated with the driving of the driving mechanism 20 that drives the optical element. Furthermore, the generated relationship information is stored in the first storage unit 52, whereby the first storage unit 52 is updated. In the following steps S200 to S206, the calibration unit 36 ​​will be described as performing each step.

[0143] The calibration unit 36 ​​acquires the position of the optical element based on at least one of the detection signal and the target position signal, and acquires sound data corresponding to the position of the optical element from the sound collected by the microphone 24 (step S200).

[0144] The calibration unit 36 ​​acquires the position of the optical element based on at least one of the detection signal and the target position signal, the driving conditions of the optical element, and sound data corresponding to the position of the optical element from the sound collected by the microphone 24. The calibration unit 36 ​​can generate sound data corresponding to the position from the sound data collected by the microphone 24 by collating the position data with the sound data.

[0145] The driving conditions of the optical element may be predetermined driving conditions. Specifically, the driving conditions of the optical element may include a step width 104 when the optical element is moved according to a target position. The driving conditions of the optical element may also include an update period 102 of the control signal. Furthermore, the driving conditions of the optical element may include an ambient environmental condition in which the imaging device 100 exists.

[0146] Next, the calibration unit 36, or the calibration unit 36 ​​and the correction coefficient output unit 322 cooperate to determine an optimal value of the correction coefficient at each position of the optical element (step S202). For example, when the calibration unit 36 ​​receives a sound generated when the drive mechanism 20 is driven and collected by the microphone 24, the calibration unit 36 ​​selects the sound generated when the drive mechanism 20 is driven from the collected sounds based on a sound pattern expressed by frequency components for each time domain corresponding to the update period 102 or the step width 104 or a time component in the time domain.

[0147] The calibration unit 36 ​​further calculates relationship information indicating the relationship between the position of the optical element and the correction coefficient from the position of the optical element and the optimal value of the correction coefficient calculated in step S202 (step S204). Next, the calibration unit 36 ​​outputs the calculated relationship information to the first storage unit 52, and the first storage unit 52 stores the updated relationship information (step S206).

[0148] For example, the calibration unit 36 ​​obtains data that associates the loudness of sound generated by driving the drive mechanism 20 with the correction coefficient to be set from the first storage unit 52. The calibration unit 36 ​​determines the correction coefficient according to the position of the optical system 10 or the image sensor 12 by referring to this data. The calibration unit 36 ​​may store information indicating the relationship between the position of the optical element and the correction coefficient in the first storage unit 52 as relationship information indicating the relationship between an index according to the loudness of sound generated by driving the drive mechanism 20 and the position of the optical element.

[0149] As another example, the calibration unit 36 ​​may perform machine learning according to a supervised learning algorithm, using the sound data as an explanatory variable and a correction coefficient capable of suppressing the loudness of the sound below a predetermined standard as an objective variable. In this way, the calibration unit 36 ​​may generate a trained prediction model that predicts an optimal correction coefficient from the sound data, and store it in the first storage unit 52. That is, the calibration unit 36 ​​may predict a correction coefficient corresponding to the sound data collected by the microphone 24 for each position of the optical element based on a trained prediction model that uses the sound data as an explanatory variable and a correction coefficient capable of suppressing the loudness of the sound below a predetermined standard as an objective variable. The algorithm in the machine learning may be any algorithm, such as a neural network, a support vector machine, a multiple regression analysis, or a decision tree.

[0150] By using the above-described updating method, the calibration unit 36 ​​can update the relationship information stored in the first storage unit 52. In this manner, even if the sound generated varies depending on the position as the drive mechanism 20 is driven, the operation of the calibration unit 36 ​​can update the relationship information appropriately and store it in the first storage unit 52.

[0151] Fig. 8B is a flow chart for explaining an example of the process of step S202 in Fig. 8A. Fig. 8B shows an example of a specific procedure for a method for generating relationship information by dividing the time components into before and after the optical element starts to be driven and while the optical element is being driven, as described with reference to Fig. 4. The procedure of this embodiment includes steps S300 to S314.

[0152] The calibration unit 36 ​​assigns 1 to a variable N for loop processing (step S300), where N=1 is the initial value of the variable N, which is an integer value.

[0153] The calibration unit 36 ​​selects data of a time domain AN (the Nth time domain) from the acquired sound data (step S302). The calibration unit 36 ​​determines whether or not the loudness of the sound generated before and after the optical element starts to drive exceeds a threshold value TH in the sound data of the time domain AN (step S304).

[0154] 3, the volume of the sound generated before and after the optical element starts to drive depends greatly on the magnitude of the rate of change of the current flowing into the voice coil motor 200. Therefore, when the volume of the sound generated before and after the optical element starts to drive exceeds the threshold value TH, the calibration unit 36 ​​adjusts the current slope (absolute value of the rate of change) or the optimal value of the coefficient related to the current magnitude so that the volume of the sound does not exceed the threshold value (step S306).

[0155] In step S304, if the loudness of the sound generated before and after the optical element starts to drive is equal to or less than the threshold value TH, the process proceeds to step S308. Alternatively, if the loudness of the sound generated before and after the optical element starts to drive exceeds the threshold value TH in step S304, the loudness of the sound is adjusted in step S306 so that it does not exceed the threshold value, and then the process proceeds to step S308.

[0156] The calibration unit 36 ​​determines whether the loudness of the sound generated while the optical element is driven exceeds the threshold value TH in the sound data of the time domain AN (step S308). As already described with reference to Fig. 3, the loudness of the sound generated while the optical element is driven depends greatly on the speed of the optical element. Therefore, if the loudness of the sound generated while the optical element is driven exceeds the threshold value TH, the calibration unit 36 ​​adjusts the optimal value of the coefficient related to the speed of the optical element or the acceleration, which is a differential value, so that the loudness of the sound does not exceed the threshold value (step S308).

[0157] In step S308, if the loudness of the sound generated while the optical element is being driven is equal to or less than the threshold value TH, the process proceeds to step S312. Alternatively, in step S308, if the loudness of the sound generated while the optical element is being driven exceeds the threshold value TH, the loudness of the sound is adjusted in step S310 so that it does not exceed the threshold value, and then the process proceeds to step S312. Note that the calibration unit 36 ​​may execute the procedures of steps S304 and S306 after the procedures of steps S308 and S310. Alternatively, the calibration unit 36 ​​may execute the procedures of steps S304 and S306 and the procedures of steps S308 and S310 in parallel.

[0158] The calibration unit 36 ​​increments the variable N to N=N+1 (step S312). The calibration unit 36 ​​determines whether the incremented value of N exceeds the number of time regions (step S314).

[0159] In step S314, if the value of N is equal to or less than the number of time regions, the process returns to step S302. On the other hand, in step S314, if the value of N is greater than the number of time regions, the process ends.

[0160] Fig. 8C is a flowchart for explaining another example of the process of step S202 in Fig. 8A. Fig. 8C shows an example of a specific procedure for a method for generating relationship information by dividing the sound generated in association with the driving of the driving mechanism 20 in each time domain, described with reference to Fig. 5, into frequency components equal to or higher than a threshold and frequency components lower than the threshold. The procedure of this embodiment includes steps S400 to S416.

[0161] The calibration unit 36 ​​assigns 1 to a variable N for loop processing (step S300), where N=1 is the initial value of the variable N, which is an integer value.

[0162] The calibration unit 36 ​​selects data of a time domain AN (the Nth time domain) from the acquired sound data (step S402). The calibration unit 36 ​​performs a Fourier transform (e.g., a fast Fourier transform (FFT)) on the sound data according to the position of the optical element, and acquires frequency characteristic data of the sound (step S404).

[0163] The calibration unit 36 ​​determines whether the loudness of the sound at a frequency below the driving band of the drive mechanism 20 exceeds a threshold value TH in the sound frequency characteristic data (step S406). As already described with reference to Fig. 3, the sound at a frequency below the driving band of the drive mechanism 20 corresponds to the sound generated while the optical element is being driven. Therefore, if the loudness of the sound at a frequency below the driving band of the drive mechanism 20 exceeds the threshold value TH, the calibration unit 36 ​​adjusts the optimal value of the coefficient related to the speed or acceleration, which is a differential value, of the optical element so that the loudness of the sound does not exceed the threshold value (step S408).

[0164] In step S406, if the loudness of the sound of the frequency below the drive band of the drive mechanism 20 is equal to or less than the threshold TH, the process proceeds to step S410. Alternatively, in step S406, if the loudness of the sound of the frequency below the drive band of the drive mechanism 20 exceeds the threshold TH, the loudness of the sound is adjusted in step S408 so that it does not exceed the threshold, and then the process proceeds to step S410.

[0165] The calibration unit 36 ​​judges whether the loudness of the sound at a frequency higher than the driving band of the driving mechanism 20 exceeds the threshold value TH in the frequency characteristic data of the sound (step S410). As already described with reference to FIG. 3, the sound at a frequency higher than the driving band of the driving mechanism 20 corresponds to the sound generated before and after the optical element starts to drive. Therefore, when the loudness of the sound at a frequency higher than the driving band of the driving mechanism 20 exceeds the threshold value TH, the calibration unit 36 ​​adjusts the optimum value of the coefficient related to the slope (absolute value of the rate of change) of the current or the magnitude of the current so that the loudness of the sound does not exceed the threshold value (step S412). Note that the calibration unit 36 ​​may execute the procedures of steps S406 and S408 after the procedures of steps S410 and S412. Alternatively, the calibration unit 36 ​​may execute the procedures of steps S406 and S408 and the procedures of steps S410 and S412 in parallel.

[0166] In step S410, if the loudness of the sound of a frequency higher than the drive band of the drive mechanism 20 is equal to or lower than the threshold value TH, the process proceeds to step S414. Alternatively, if the loudness of the sound of a frequency higher than the drive band of the drive mechanism 20 exceeds the threshold value TH in step S410, the loudness of the sound is adjusted in step S412 so that it does not exceed the threshold value, and then the process proceeds to step S410.

[0167] The calibration unit 36 ​​increments the variable N to N=N+1 (step S414). The calibration unit 36 ​​determines whether the incremented value of N exceeds the number of time regions (step S416).

[0168] In step S416, if the value of N is equal to or less than the number of time regions, the process returns to step S402. On the other hand, in step S416, if the value of N is greater than the number of time regions, the process ends.

[0169] 8B or 8C, it is possible to derive optimal correction coefficients and related information even if the sound at a specific position of the optical element increases when the drive mechanism 20 is driven due to aging deterioration of the support mechanism for the optical element, etc. Based on these, the drive mechanism control unit 30 can reduce the sound generated by driving the drive mechanism 20 without significantly reducing the drive speed of the entire drive control by the drive mechanism 20.

[0170] 9 is a block diagram showing an example of the configuration of a processing unit 90 provided outside the imaging device 100. In the figure, the processing unit 90 outside the imaging device 100 and the storage unit 50 inside the imaging device 100 are shown.

[0171] The processing unit 90 is, for example, a hardware resource that is connected to the imaging device 100 before shipment from a factory and functions as a processing device that performs various information processing. The processing unit 90 is, for example, a personal computer having a processor, a workstation, or a server device. The processing unit 90 includes a relationship information generating unit 92.

[0172] The relationship information generating unit 92 generates relationship information based on sound information indicating the volume of sound corresponding to the position of the optical element generated by driving the driving mechanism 20 according to predetermined driving conditions, and correction coefficient information indicating the relationship between the volume of the sound and the correction coefficient. That is, the relationship information generating unit 92 may perform the same function as the calibration unit 36 ​​in Fig. 2B with respect to updating the relationship information, but is configured outside the imaging device 100 where the magnetic sensor 22, the driving mechanism control unit 30, etc. may be provided.

[0173] As already described, the drive mechanism control unit 30 functions as a control device that generates a control signal for controlling the drive mechanism for moving the optical element to a target position while suppressing the sound generated by the drive mechanism 20 that drives the optical element. Therefore, the processing unit 90 includes a relationship information generating unit 92 that generates relationship information, and thereby functions as a relationship information generating device that generates relationship information that indicates the relationship between the position of the optical element and a correction coefficient of the control signal corresponding to the magnitude of the sound generated by the drive mechanism 20, which is referenced by the control device.

[0174] The storage unit 50 is the same as the storage unit described with reference to Figures 1, 2A, and 2B. The storage unit 50 stores the relationship information generated by the relationship information generation unit 92.

[0175] When the processing unit 90 is not provided in the imaging device 100, it may be necessary to update the related information due to deterioration over time of the support unit for the optical element, the driving mechanism 20, etc. In such a case, for example, the processing unit 90 may be an information processing device provided in a repair shop, a customer support center, etc., and may be an information processing device capable of communicating with the imaging device 100 via wired or wireless communication.

[0176] For example, when the processing unit 90 is provided in an information processing device capable of wireless communication, the storage unit 50 stores sound data corresponding to the position where sound is collected by the microphone and the volume of the sound for each frequency component included in the sound data, or the volume of the sound generated before and after the optical element starts to drive and the sound generated while the optical element is driving. The imaging device 100 transmits such data to the processing unit 90 provided externally, and receives related information from the processing unit 90. The storage unit 50 then stores the received related information.

[0177] As described above, the processing unit 90 provided outside the imaging device 100 can also update the relationship information.

[0178] Although the present invention has been described above using the embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It is clear to those skilled in the art that various modifications and improvements can be made to the above embodiments. It is clear from the description of the claims that such modifications and improvements can also be included in the technical scope of the present invention.

[0179] It should be noted that the order of execution of each process, such as operations, procedures, steps, and stages, in the devices, systems, programs, and methods shown in the claims, specifications, and drawings is not specifically stated as "before," "prior to," etc., and may be realized in any order unless the output of a previous process is used in a later process. Even if the operational flow in the claims, specifications, and drawings is explained using "first," "next," etc. for convenience, it does not mean that it is essential to perform the process in this order. [Explanation of symbols]

[0180] 10 Optical system 12 Image sensor 20 Drive mechanism 22 Magnetic Sensor 24. Mike 30 Drive mechanism control section 32 Generation part 40 Imaging control section 50 Storage section 52 1st memory section 54 2nd memory section 60 Display section 70 Operation section 80,82 curve 90 Processing section 92 Relationship Information Generation Unit 100 Imaging device 102 Update cycle 104 Step Width 36 Calibration section 112,114 Peak 200 Voice coil motor 202 Motor driver 322 Correction coefficient output section 324 PID control unit

Claims

1. An IC chip for controlling a drive mechanism that drives an optical element based on a control signal, The IC chip includes a generation unit that generates the control signal for moving the optical element to a target position while suppressing sound generated by driving the driving mechanism, based on a detection signal indicating the position of the optical element and relationship information indicating the relationship between an index corresponding to the loudness of sound generated by driving the driving mechanism and the position of the optical element.

2. The IC chip described in claim 1, wherein the generation unit generates the control signal corresponding to the position of the optical element based on the relationship information in order to suppress noise generated by driving the driving mechanism by suppressing the speed or acceleration at which the optical element moves.

3. The IC chip described in claim 1, wherein the generation unit generates the control signal corresponding to the position of the optical element based on the relationship information in order to suppress sound generated by driving the driving mechanism by suppressing at least one of the magnitude of the rate of change of the current supplied to the driving mechanism and the magnitude of the current.

4. the relationship information indicates, as the index, a correction coefficient for correcting the control signal in accordance with a volume of a sound generated in association with the driving of the drive mechanism; The IC chip described in claim 1, wherein the generation unit identifies a position of the optical element based on at least one of the detection signal and a target position signal indicating the target position, identifies the correction coefficient corresponding to the identified position of the optical element by referring to the relationship information, and generates the control signal based on the correction coefficient corresponding to the position of the optical element, the target position signal, and the detection signal.

5. 5. The IC chip according to claim 4, wherein the generation unit generates the control signal for PID control of the drive mechanism by performing arithmetic operations on at least one of a proportional component, a differential component, and an integral component based on a deviation between the target position signal and the detection signal, based on the correction coefficient corresponding to the position of the optical element, the target position signal, and the detection signal.

6. the generation unit generates the control signal for correcting a gain of a driving band of the driving mechanism by four arithmetic operations using the correction coefficient according to a position of the optical element; The IC chip according to claim 5 , wherein the driving band is equal to or less than 200 Hz.

7. The IC chip according to claim 1 , further comprising a storage unit that stores the relationship information.

8. the relationship information indicates, as the index, a correction coefficient for correcting the control signal in accordance with a volume of a sound generated in association with the driving of the drive mechanism; The IC chip described in claim 2, wherein the generation unit identifies a position of the optical element based on at least one of the detection signal and a target position signal indicating the target position, identifies the correction coefficient corresponding to the identified position of the optical element by referring to the relationship information, and generates the control signal based on the correction coefficient, the target position signal, and the detection signal.

9. the relationship information indicates, as the index, a correction coefficient for correcting the control signal in accordance with a volume of a sound generated in association with the driving of the drive mechanism; The IC chip described in claim 3, wherein the generation unit identifies a position of the optical element based on at least one of the detection signal and a target position signal indicating the target position, identifies the correction coefficient corresponding to the identified position of the optical element by referring to the relationship information, and generates the control signal based on the correction coefficient, the target position signal, and the detection signal.

10. the IC chip is operable in a correction mode in which the control signal is corrected based on the relationship information and in a non-correction mode in which the control signal is not corrected based on the relationship information; The IC chip according to any one of claims 1 to 9, wherein the generation unit generates the control signal for moving the optical element to a target position while suppressing noise generated by driving the driving mechanism based on the detection signal and the relationship information while the IC chip is operating in the correction mode.

11. A magnetic sensor that outputs the detection signal is further provided. The IC chip according to claim 10 , wherein the magnetic sensor includes a plurality of Hall elements.

12. the relationship information indicates, as the index, a correction coefficient for correcting the control signal in accordance with a volume of a sound generated in association with the driving of the drive mechanism; the generation unit generates the control signal based on the correction coefficient corresponding to a position of the optical element, a target position signal indicating the target position, and the detection signal; The IC chip includes: The IC chip according to any one of claims 1 to 9, further comprising a calibration unit that generates or updates the relationship information based on sound information indicating the loudness of a sound generated in accordance with driving of the driving mechanism according to predetermined driving conditions and depending on the position of the optical element, and correction coefficient information indicating the relationship between the loudness of the sound and a correction coefficient.

13. The IC chip according to claim 12 , wherein the predetermined driving conditions include a step width indicating a distance by which the optical element is moved according to the target position, and an update period of the target position.

14. The calibration unit includes: when a sound generated before and after the optical element starts to be driven is equal to or greater than a predetermined volume, a correction coefficient for suppressing the sound is adjusted so that a rate of change of a current supplied to the drive mechanism becomes small, thereby executing a process of generating or updating the relationship information for each step width or each update period; The IC chip described in claim 13, wherein, when a sound generated while the optical element is being driven in conjunction with the driving of the driving mechanism is equal to or greater than a predetermined volume, a correction coefficient for suppressing the sound is adjusted so that a rate or volume of change in the driving speed of the driving mechanism is suppressed, thereby executing a process of generating or updating the relationship information for each step width or each update period.

15. The calibration unit includes: Identifying a frequency component of a sound generated in association with the driving of the drive mechanism based on the sound information; when a frequency component of a first frequency band is included in the frequency components of the sound having a loudness equal to or greater than a predetermined loudness, a process of generating or updating the relationship information is executed for each of the step widths or each of the update periods by adjusting the correction coefficient so as to suppress a rate of change or a magnitude of a change in the drive speed of the drive mechanism; when frequency components of the sound having a volume equal to or greater than a predetermined volume include frequency components of a second frequency band higher than the first frequency band, the correction coefficient is adjusted so that a rate of change of the current supplied to the drive mechanism becomes smaller, thereby executing a process of generating or updating the relationship information for each step width or each update period; The IC chip of claim 13 , wherein the first frequency band is equal to or lower than a driving band of the driving mechanism, and the second frequency band is higher than a driving band of the driving mechanism.

16. A control method for controlling a drive mechanism that drives an optical element based on a control signal, comprising: A control method comprising a step of generating a control signal for moving the optical element to a target position while suppressing sound generated by driving the driving mechanism, based on a detection signal indicating the position of the optical element and relationship information indicating the relationship between an index corresponding to the loudness of sound generated by driving the driving mechanism and the position of the optical element.

17. A method for generating relationship information indicating a relationship between a position of an optical element and a correction coefficient of a control signal corresponding to a magnitude of a sound generated by driving a drive mechanism, the correction coefficient being referenced by a control device that generates a control signal for controlling a drive mechanism that drives an optical element and moves the optical element to a target position while suppressing a sound generated by the drive mechanism, the control device comprising: A generation method comprising a step of generating the relationship information based on sound information indicating the loudness of a sound corresponding to the position of the optical element generated in conjunction with driving of the drive mechanism in accordance with predetermined drive conditions, and correction coefficient information indicating the relationship between the loudness of the sound and a correction coefficient.

18. The generation method according to claim 17 , wherein the predetermined drive conditions include a step width indicating a distance by which the optical element is moved according to the target position, and an update period of the target position.

19. The generating step includes: a step of executing a process of generating the relationship information for each of the step widths or the update period by adjusting a correction coefficient for suppressing the sound so that a rate of change of the current supplied to the drive mechanism becomes small when the sound generated before and after the optical element starts to drive is equal to or larger than a predetermined volume; a step of executing a process of generating the relationship information for each of the step widths or each of the update periods by adjusting a correction coefficient for suppressing the sound so that a rate of change or a magnitude of a drive speed of the drive mechanism is suppressed when the sound generated while the optical element is being driven in accordance with the drive mechanism is equal to or greater than a predetermined volume; 20. The method of claim 18, comprising:

20. The generating step includes: identifying a frequency component of a sound generated in association with the driving of the drive mechanism based on the sound information; a step of executing a process of generating the relationship information for each of the step widths or the update period by adjusting the correction coefficient so as to suppress a rate of change or a magnitude of a drive speed of the drive mechanism when a frequency component of the sound having a volume equal to or greater than a predetermined volume includes a frequency component of a first frequency band; a step of executing a process of generating the relationship information for each of the step widths or the update period by adjusting the correction coefficient so that a rate of change of the current supplied to the drive mechanism becomes small when frequency components of the sound having a volume equal to or greater than a predetermined volume include frequency components of a second frequency band higher than the first frequency band; Including, 20. The method of claim 18, wherein the first frequency band is equal to or less than a drive band of the drive mechanism, and the second frequency band is higher than a drive band of the drive mechanism.

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