Drive unit and drive method

Abstract

To correct a tilt of a lens due to unbalance in drive capability among a plurality of drive sources according to a position of the lens.SOLUTION: A driving device is provided, which comprises: a calculation unit that calculates a driving amount of an optical element based on a detected position of the optical element and a target position of the optical element; a correction unit into which the driving amount, the detected position, and the target position are input, and which generates a corrected driving amount by correcting the driving amount based on the driving amount, a parameter corresponding to the tilt of the optical element, and one of the detection position and the target position, and outputs the driving amount and the corrected driving amount; a first driving unit that applies a first driving force corresponding to either one of the driving amount and the corrected driving amount to a first driving source among a plurality of driving sources for moving the optical element in a predetermined direction; and a second driving unit that applies a second driving force corresponding to the other of the driving amount and the corrected driving amount to a second driving source of the plurality of driving sources.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a drive device and a drive method.

Background Art

[0002] Patent Document 1 describes that "the controller applies a predetermined offset force to the driving force generated in one driving source and controls the driving force of the other driving source to compensate for the imbalance in the driving force caused by the offset force." [Prior Art Document] [Patent Document] [Patent Document 1] JP-A-2018-045484

Summary of the Invention

[0003] In a first aspect of the present invention, a drive device is provided. The drive device may include a calculation unit that calculates a driving amount of the optical element based on a detection position of the optical element and a target position of the optical element. The drive device may include a correction unit that receives the driving amount, the detection position, and the target position, generates a corrected driving amount obtained by correcting the driving amount based on the driving amount, a parameter corresponding to the inclination of the optical element, and either the detection position or the target position, and outputs the driving amount and the corrected driving amount. The drive device may include a first drive unit that applies a first driving force corresponding to either the driving amount or the corrected driving amount to a first drive source among a plurality of drive sources for moving the optical element in a predetermined direction. The drive device may include a second drive unit that applies a second driving force corresponding to the other of the driving amount and the corrected driving amount to a second drive source among the plurality of drive sources.

[0004] The correction unit may correct the driving amount based on a function of the detection position.

[0005] If a predetermined first coefficient is referred to as "coefficient 1" and a predetermined second coefficient as "coefficient 2", the correction unit may correct the drive current corresponding to the drive amount calculated by the calculation unit using the formula "corrected drive current = drive current × coefficient 1 + drive current × detection position × coefficient 2".

[0006] The correction unit may correct the drive amount using a predefined correction table based on the detection position and the drive amount.

[0007] The correction unit described above may correct the drive amount based on a function of the target position described above.

[0008] If a predetermined first coefficient is referred to as "coefficient 1" and a predetermined second coefficient as "coefficient 2", the correction unit may correct the drive current corresponding to the drive amount calculated by the calculation unit using the formula "corrected drive current = drive current × coefficient 1 + drive current × target position × coefficient 2".

[0009] The correction unit may correct the drive amount using a predefined correction table based on the target position and the drive amount.

[0010] The correction unit described above may be configured to allow switching between using either the detection position or the target position for correcting the drive amount.

[0011] The correction unit may have a switching unit that switches between correction using either the detection position or the target position, and correction without using the detection position or the target position, depending on the characteristics of the first drive source and the second drive source.

[0012] The correction unit may select which of the multiple drive sources to use as a reference to correct the drive amount based on a parameter corresponding to the tilt of the optical element.

[0013] The parameter corresponding to the above tilt may indicate the tilt of the optical element detected when the maximum current is applied to each of the multiple drive sources.

[0014] The calculation unit may calculate the drive amount by feedback control using the detected position and the target position.

[0015] A second embodiment of the present invention provides a driving method. The driving method may be a method for driving a plurality of drive sources, including a first drive source and a second drive source. The driving method may include detecting the tilt of an optical element. The driving method may include generating parameters corresponding to the tilt of the optical element. The driving method may include detecting the position of the optical element and outputting the detected position. The driving method may include calculating a drive amount for the optical element based on the detected position of the optical element and the target position of the optical element. The driving method may include generating a corrected drive amount by correcting the drive amount based on the drive amount, parameters corresponding to the tilt of the optical element, and either the detected position or the target position. The driving method may include selecting which of the first drive source and the second drive source to drive with a drive force corresponding to the corrected drive amount, based on the parameters corresponding to the tilt of the optical element.

[0016] It should be noted that the above summary of the invention does not enumerate all of its features. Furthermore, subcombinations of these features may also constitute an invention. [Brief explanation of the drawing]

[0017] [Figure 1] An example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to this embodiment is shown. [Figure 2] This diagram shows an example of the flow in which the drive unit 100 according to this embodiment performs tilt correction processing. [Figure 3] An example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the second embodiment is shown. [Figure 4] An example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the third embodiment is shown. [Figure 5] An example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the fourth embodiment is shown. [Figure 6] An example of a block diagram of the correction unit 130 in the drive unit 100 according to the fifth embodiment is shown. [Figure 7] An example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the sixth embodiment is shown. [Modes for carrying out the invention]

[0018] The present invention will be described below through embodiments of the invention, but these embodiments are not intended to limit the invention as defined in the claims. Furthermore, not all combinations of features described in the embodiments are necessarily essential to the solution of the invention.

[0019] Figure 1 shows an example of a block diagram of a camera module 10 which may be equipped with the drive unit 100 according to this embodiment. Note that these blocks are functionally separated functional blocks and do not necessarily correspond to the actual device configuration. That is, just because a block is shown as a single block in this figure does not necessarily mean that it is composed of a single device. Similarly, just because blocks are shown as separate blocks in this figure does not necessarily mean that they are composed of separate devices. The same applies to other figures.

[0020] Furthermore, hereinafter, the camera module 10 will be described as an example, but it is not limited thereto. A portable electronic device or a position control system having the same functions as the camera module 10 described below may be provided. Examples of such devices include mobile phones, smartphones, tablet terminals, PDAs, portable computers, laptops, and notebook personal computers, as well as systems built into or externally attached to these devices to control the position of the lens. Also, in the description, a lens is cited as an example of an optical element, but it may be an image sensor instead of just a lens.

[0021] The camera module 10 may be capable of executing processes such as autofocus (AF) and zoom. In the present embodiment, the camera module 10 executes tilt correction processing for correcting the inclination of the lens in conjunction with or independently of the above processes.

[0022] The camera module 10 includes an object 20, a plurality of drive sources 50, a processor 70, and a driving device 100.

[0023] The object 20 is a device to be driven. Hereinafter, the case where the object 20 is a lens barrel will be described as an example. The object 20 is integrally provided with a lens 30, a first magnet 40_1, and a second magnet 40_2 (collectively referred to as "magnet 40").

[0024] The lens 30 is an optical element for refracting and focusing light. When the camera module 10 executes AF processing or Zoom processing, the lens 30 is linearly moved along the optical axis direction to perform focusing and image enlargement / reduction.

[0025] The magnet 40 is a permanent magnet. In this embodiment, one example is shown in which a first magnet 40_1 and a second magnet 40_2 are provided as the magnet 40. The first magnet 40_1 and the second magnet 40_2 may be provided, for example, along the optical axis of the lens 30 at positions facing each other with the lens 30 in between.

[0026] The multiple drive sources 50 are sources of thrust for moving the lens 30 in a predetermined direction, in this case, along the optical axis of the lens 30. In this embodiment, one example is shown where the multiple drive sources 50 include a first drive source 50_1 and a second drive source 50_2. Each of the multiple drive sources 50 may include, for example, a coil. The first drive source 50_1 may include a coil wound along the optical axis of the lens 30 in the vicinity of the first magnet 40_1. Similarly, the second drive source 50_2 may include a coil wound along the optical axis of the lens 30 in the vicinity of the second magnet 40_2. In such multiple drive sources 50, when a drive current or drive voltage is supplied to provide a driving force, magnetic forces are generated between the first drive source 50_1 and the first magnet 40_1, and between the second drive source 50_2 and the second magnet 40_2, respectively. These magnetic forces act as thrust, allowing the position of the lens 30 to be moved.

[0027] The processor 70 is a processing unit responsible for controlling the camera module 10. The processor 70 may be connected to the drive unit 100 in a communicative manner via, for example, serial communication, parallel communication, a network, or wireless communication. As an example, I2C (Inter-Integrated Circuit) may be used for such communication. The processor 70 may supply the drive unit 100 with a target position signal indicating the target position of the lens 30. The processor 70 may also supply the drive unit 100 with tilt information indicating the tilt of the lens 30.

[0028] The drive unit 100 acquires a target position signal and tilt information from the processor 70. The drive unit 100 then calculates the amount of drive for the lens 30 based on the detected position of the lens 30 and the target position, and provides a driving force to the multiple drive sources 50 according to the calculation result. At this time, the drive unit 100 according to this embodiment corrects the amount of drive calculated based on the position of the lens 30 and the tilt of the lens 30.

[0029] The drive unit 100 includes a position sensor 110, a calculation unit 120, a correction unit 130, and a plurality of drive units 140. In this figure, the case in which the plurality of drive units 140 have a first drive unit 140_1 and a second drive unit 140_2 is shown as an example.

[0030] The position sensor 110 detects the position of the lens 30. The position sensor 110 may be, for example, a magnetic sensor, and may detect the position of the lens 30 by detecting the magnetic field generated by a magnet 40 integrally provided with the lens 30. Such a magnetic sensor may be, for example, a silicon Hall element or a compound Hall element, which applies the Hall effect and detects changes in the external magnetic field from the generated electromotive force. However, it is not limited to this. The magnetic sensor may be a spin valve type magnetoresistive element (GMR element, TMR element, etc.) whose resistance changes in response to changes in the external magnetic field, or any other sensor capable of detecting a magnetic field, or a combination of these various sensors. The position sensor 110 may also be composed of a group of sensor elements consisting of multiple sensor elements. Furthermore, the position sensor 110 may amplify the detected amplitude voltage or current value by a factor of 1 or more, or convert it to a digital value by A / D conversion. The position sensor 110 supplies a detected position signal indicating the detected position of the lens 30 to the calculation unit 120. In this embodiment, the position sensor 110 supplies the detected position signal to the calculation unit 120 and then to the correction unit 130. While this figure shows an example where the position sensor 110 is built into the drive unit 100, the position sensor 110 may be configured separately from the drive unit 100 and externally attached to it.

[0031] The calculation unit 120 calculates the amount of drive for the optical element (lens 30) based on the detection position of the optical element and the target position of the optical element. In this case, the calculation unit 120 may perform PID calculation. Here, PID is a type of feedback control that controls the input value using three elements: the deviation between the output value and the target value, its integral, and its derivative. A basic feedback control is proportional control (P control). This controls the input value as a linear function of the deviation between the output value and the target value. The action of changing the input value in proportion to this deviation is called proportional action or P action (P stands for Proportional). In other words, if a state with a deviation continues for a long time, it plays the role of increasing the change in the input value to bring it closer to the target value. Also, the action of changing the input value in proportion to the integral of this deviation is called integral action or I action (I stands for Integral). Control that combines proportional action and integral action in this way is called PI control. Furthermore, the operation of changing the input value in proportion to the derivative of this deviation is called differential operation or D operation (D stands for Derivative or Differential). Control that combines such proportional operation, integral operation, and differential operation is called PID. In other words, the calculation unit 120 calculates the amount of drive of the lens 30 by performing a PID operation based on the detected position of the lens 30 detected by the position sensor 110 and the target position of the lens 30 specified by the processor 70. In other words, the calculation unit 120 performs closed-loop feedback control to move the lens 30 to the target position based on the result of detecting the position of the lens 30. For example, in this way, the calculation unit 120 can calculate the amount of drive by feedback control using the detected position and the target position. The calculation unit 120 supplies the calculation result, that is, information indicating the amount of drive of the lens 30, to the correction unit 130.

[0032] The correction unit 130 receives the drive amount, detection position, and target position as input, and generates a corrected drive amount by correcting the drive amount based on the drive amount, a parameter corresponding to the tilt of the optical element (lens 30), and either the detection position or the target position, and outputs the drive amount and the corrected drive amount. In this embodiment, the correction unit 130 corrects the drive amount of the lens 30 based on the detection position of the lens 30 and the tilt of the lens 30. The correction unit 130 outputs the drive amount and the corrected drive amount to a plurality of drive units 140. Here, regarding the parameter corresponding to the tilt of the lens 30, tilt information at each lens position may be acquired in advance during an actuator inspection process, etc., and the correction unit 130 may perform the correction based on the previously acquired tilt information during actual operation.

[0033] The first drive unit 140_1 provides a first drive force, corresponding to either the drive amount or the corrected drive amount, to the first drive source 50_1, which is one of a plurality of drive sources 50 for moving the lens 30 in a predetermined direction. More specifically, the first drive unit 140_1 provides the first drive force to the first drive source 50_1 by supplying a drive current and a drive voltage to the first drive source 50_1, corresponding to either the drive amount calculated by the calculation unit 120 or the corrected drive amount generated by the correction unit 130.

[0034] The second drive unit 140_2 provides a second driving force to the second drive source 50_2 among the multiple drive sources 50, corresponding to the other of either the drive amount or the corrected drive amount. More specifically, the second drive unit 140_2 provides the second driving force to the second drive source 50_2 by supplying a drive current and a drive voltage corresponding to the other of either the drive amount calculated by the calculation unit 120 or the corrected drive amount generated by the correction unit 130.

[0035] When such drive currents and drive voltages are supplied to multiple drive sources 50, magnetic forces are generated between the first drive source 50_1 and the first magnet 40_1, and between the second drive source 50_2 and the second magnet 40_2. These forces act as thrust, allowing the lens 30 to move. The drive device 100 then detects the position of the moved lens 30 with the position sensor 110 and feeds this back to the calculation unit 120, thereby moving the lens 30 to the desired position. In this embodiment, the drive device 100 corrects the drive capability of either the first drive source 50_1 or the second drive source 50_2 in the correction unit 130, so that the lens 30 can be moved without tilting relative to the optical axis.

[0036] The correction unit 130 may be able to select which of the multiple drive sources 50 to use as a reference for correcting the drive amount. This will be explained in detail using a flowchart.

[0037] Figure 2 shows an example of the flow in which the drive device 100 according to this embodiment performs tilt correction processing. In step S210, the drive device 100 supplies the maximum current to the multiple drive sources 50. For example, the multiple drive units 140 supply drive current to each of the multiple drive sources 50 so as to be the maximum current.

[0038] In step S220, the drive unit 100 acquires tilt information indicating the tilt of the lens 30. For example, the correction unit 130 acquires tilt information indicating the tilt of the lens 30 from the processor 70. In this case, the parameter corresponding to the tilt of the optical element (lens 30) will indicate the tilt of the lens 30 detected when the maximum current is applied to each of the multiple drive sources 50. Steps S210 and S220 may be performed as part of the actuator inspection process.

[0039] In step S230, the drive unit 100 checks the drive capability. For example, the correction unit 130 checks whether the lens 30 is tilted towards the first drive source 50_1 or the second drive source 50_2 based on the tilt information acquired in step S220. Generally, the drive capability of a drive source 50 depends on the mechanical characteristics of the actuator. In this case, the lens 30 moves more towards the drive source with higher drive capability, so if there is a difference in the drive capabilities of the multiple drive sources 50, the lens 30 will tilt with respect to the optical axis. Here, it is difficult to correct the drive source with lower drive capability to match the drive source with higher drive capability. Therefore, the drive unit 100 according to this embodiment corrects the drive source with higher drive capability to match the drive source with lower drive capability. Accordingly, the correction unit 130 should select which of the multiple drive sources 50 to use as a reference to correct the amount of drive based on a parameter corresponding to the tilt of the optical element (lens 30).

[0040] If the drive capacity of the first drive source 50_1 is determined to be lower based on the tilt of the lens 30, the drive device 100 proceeds to step S240. On the other hand, if the drive capacity of the second drive source 50_2 is determined to be lower based on the tilt of the lens 30, the drive device 100 proceeds to step S250.

[0041] In step S240, the drive unit 100 corrects the drive amount calculated by the calculation unit 120 in order to correct the drive capacity of the second drive source 50_2, based on the first drive source 50_1.

[0042] In this embodiment, the correction unit 130 corrects the drive amount calculated by the calculation unit 120 based on the detection position of the lens 30 and the tilt of the lens 30. For example, if a predetermined first coefficient is "coefficient 1" and a predetermined second coefficient is "coefficient 2", the correction unit 130 corrects the drive current corresponding to the drive amount calculated by the calculation unit 120 using, for example, the following formula: "Corrected drive current = drive current × coefficient 1 + drive current × detection position × coefficient 2". That is, the correction unit 130 corrects the drive amount based on a function of the detection position of the lens 30. More specifically, the correction unit 130 corrects the drive amount by the sum of a function in which the drive current corresponding to the drive amount calculated by the calculation unit 120 and the predetermined coefficient 1 are variables, and a function in which the drive current corresponding to the drive amount calculated by the calculation unit 120, the detection position of the lens 30 and the predetermined coefficient 2 are variables. Here, at least one of "Coefficient 1" and "Coefficient 2" may be predefined to be a numerical value corresponding to the magnitude of the tilt of the lens 30.

[0043] In the above explanation, the case in which the correction unit 130 corrects the drive amount based on a function of the detected position of the lens 30 was shown as an example, but it is not limited to this. The correction unit 130 may also correct the drive amount using a predefined correction table based on the detected position of the lens 30 and the drive amount.

[0044] The correction unit 130 then outputs a corrected drive amount, which is the corrected drive amount, to the second drive unit 140_2. In response, the second drive unit 140_2 provides a second drive force corresponding to the corrected drive amount to the second drive source 50_2 among the multiple drive sources 50. More specifically, the second drive unit 140_2 provides the second drive force to the second drive source 50_2 by supplying the corrected drive current to the second drive source 50_2. On the other hand, the correction unit 130 outputs the drive amount before correction, that is, the drive amount calculated by the calculation unit 120, to the first drive unit 140_1. In response, the first drive unit 140_1 provides a first drive force corresponding to the drive amount before correction to the first drive source 50_1 among the multiple drive sources 50. More specifically, the first drive unit 140_1 supplies the drive current before correction to the first drive source 50_1, thereby providing the first drive force to the first drive source 50_1. In this way, the drive device 100 corrects the drive capacity of the second drive source 50_2 using the first drive source 50_1, which has the lowest drive capacity, as a reference.

[0045] On the other hand, in step S250, the drive unit 100 corrects the drive amount calculated by the calculation unit 120 in order to correct the drive capacity of the first drive source 50_1, based on the second drive source 50_2. Note that the correction of the drive amount may be the same as in step S240, so a detailed explanation is omitted here.

[0046] The correction unit 130 then supplies the corrected drive amount, which is the corrected drive amount, to the first drive unit 140_1. In response, the first drive unit 140_1 provides a first drive force corresponding to the corrected drive amount to the first drive source 50_1 among the multiple drive sources 50. More specifically, the first drive unit 140_1 provides the first drive force to the first drive source 50_1 by supplying the corrected drive current to the first drive source 50_1. On the other hand, the correction unit 130 outputs the drive amount before correction, that is, the drive amount calculated by the calculation unit 120, to the second drive unit 140_2. In response, the second drive unit 140_2 provides a second drive force corresponding to the drive amount before correction to the second drive source 50_2 among the multiple drive sources 50. More specifically, the second drive unit 140_2 supplies the uncorrected drive current to the second drive source 50_2, thereby providing the second drive force to the second drive source 50_2. In this way, the drive device 100 corrects the drive capacity of the first drive source 50_1 using the second drive source 50_2, which has the lowest drive capacity, as a reference.

[0047] In recent years, due to the increasing size and weight of lenses, multiple drive sources are sometimes used to move the lens in order to improve its driving force. However, in such cases, if there is a variation in the driving ability among the multiple drive sources, the lens may tilt.

[0048] Patent Document 1 describes a technique for compensating for imbalances in the driving capabilities of drive sources by adding an offset to the driving amount. However, Patent Document 1 does not mention anything about correcting the tilt of an object due to imbalances in driving capabilities. Furthermore, if the driving current is supplied directly to multiple drive units without correcting the calculated driving amount, the lens may tilt when moved in the optical axis direction due to variations in the driving capabilities of the multiple drive sources. Moreover, even if the driving amount is corrected without considering the position of the lens, such as corrected driving current = driving current × coefficient 1 + coefficient 2, if the driving capabilities of the multiple drive sources change depending on the position of the lens, there is a problem that the tilt can be corrected at a position x1 of the lens, but not at another position x2.

[0049] In contrast, the drive device 100 according to this embodiment corrects the amount of drive based on the detected position of the lens 30 and the tilt of the lens 30. The drive device 100 according to this embodiment then provides a first drive force to the first drive source corresponding to either the amount of drive before correction or the amount of drive after correction, and provides a second drive force to the second drive source corresponding to either the amount of drive before correction or the amount of drive after correction. As a result, with the drive device 100 according to this embodiment, even when multiple drive sources 50 are used to move the lens in a predetermined direction, the tilt of the lens 30 due to an imbalance in the driving capabilities among the multiple drive sources 50 can be corrected according to the position of the lens 30.

[0050] In this case, the drive unit 100 according to this embodiment may correct the drive amount based on a function of the detected position. This allows the drive unit 100 according to this embodiment to perform appropriate correction calculations according to the position of the lens 30 that is actually detected. Alternatively, the drive unit 100 according to this embodiment may correct the drive amount using a predefined correction table based on the detected position and the drive amount. This allows the drive unit 100 according to this embodiment to reduce the processing load of the correction calculation based on the detected position.

[0051] Furthermore, the drive device 100 according to this embodiment may select which of the multiple drive sources 50 to use as a reference for correcting the amount of drive based on the tilt of the lens 30. In this case, the drive device 100 according to this embodiment may use the tilt of the lens 30 detected when the maximum current is applied to each of the multiple drive sources 50 as the tilt of the lens 30. As a result, the drive device 100 according to this embodiment can, after confirming the driving capacity of the multiple drive sources 50 based on the tilt of the lens 30 when the maximum current is actually applied, correct the one with the higher driving capacity to match the one with the lower driving capacity, for example.

[0052] Figure 3 shows an example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the second embodiment. In this figure, the same reference numerals are used for components having the same function and configuration as in Figure 1, and descriptions are omitted below except for differences. In the above embodiment, one example was shown in which the drive device 100 performs tilt correction processing based on the detected position of the lens 30 and the tilt of the lens 30. In the second embodiment, the drive device 100 performs tilt correction processing based on the target position of the lens 30 and the tilt of the lens 30.

[0053] In the second embodiment, the correction unit 130 acquires a target position signal from the processor 70, instead of acquiring a detection position signal from the position sensor 110 that indicates the detection position of the lens 30.

[0054] In the second embodiment, the correction unit 130 corrects the drive amount calculated by the calculation unit 120 based on the target position of the lens 30 and the tilt of the lens 30. As an example, the correction unit 130 corrects the drive current corresponding to the drive amount calculated by the calculation unit 120 using, for example, the following formula: "Corrected drive current = drive current × coefficient 1 + drive current × target position × coefficient 2". That is, the correction unit 130 corrects the drive amount based on a function of the target position of the lens 30. More specifically, the correction unit 130 corrects the drive amount by the sum of a function in which the drive current corresponding to the drive amount calculated by the calculation unit 120 and a predetermined coefficient 1 are variables, and a function in which the drive current corresponding to the drive amount calculated by the calculation unit 120, the target position of the lens 30 and a predetermined coefficient 2 are variables. Here, at least one of "coefficient 1" and "coefficient 2" may be predetermined to be a numerical value corresponding to the magnitude of the tilt of the lens 30.

[0055] In the above explanation, the case in which the correction unit 130 corrects the drive amount based on a function of the target position of the lens 30 was shown as an example, but it is not limited to this. The correction unit 130 may also correct the drive amount using a predefined correction table based on the target position of the lens 30 and the drive amount.

[0056] Thus, the drive unit 100 according to the second embodiment corrects the drive amount based on a function of the target position rather than the detected position. As a result, the drive unit 100 according to the second embodiment can perform appropriate correction calculations according to the target position of the lens 30 specified by the processor 70, rather than the position of the lens 30 that is actually detected. Furthermore, the drive unit 100 according to the second embodiment may correct the drive amount using a predefined correction table based on the target position and the drive amount. As a result, the drive unit 100 according to the second embodiment can also reduce the processing load of correction calculations based on the target position.

[0057] In the above description, tilt correction processing based on the detected position and tilt correction processing based on the target position were shown as separate embodiments. However, these tilt correction processes may be used in combination. That is, the drive unit 100 may perform tilt correction processing based on the detected position of the lens, the target position, and the tilt of the lens. As a result, the drive unit 100 can perform correction calculations according to both the position of the lens 30 that is actually detected and the target position of the lens 30 specified by the processor 70.

[0058] Figure 4 shows an example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the third embodiment. In this figure, the same reference numerals are used for components having the same function and configuration as in Figure 1, and descriptions are omitted below except for differences. In the above embodiment, the case in which the camera module 10 moves the lens 30 using two drive sources was shown as an example. However, it is not limited to this. The camera module 10 may move the lens 30 using three or more drive sources.

[0059] In the third embodiment, as an example, a case is shown in which the multiple drive sources 50 have a third drive source 50_3 in addition to the first drive source 50_1 and the second drive source 50_2. Correspondingly, the multiple drive units 140 have a third drive unit 140_3 in addition to the first drive unit 140_1 and the second drive unit 140_2. The third drive unit 140_3 supplies a third drive force to the third drive source 50_3 of the multiple drive sources 50, corresponding to either the drive amount or the corrected drive amount. More specifically, the third drive unit 140_3 supplies a drive current or drive voltage to the third drive source 50_3 corresponding to either the drive amount calculated by the calculation unit 120 or the corrected drive amount generated by the correction unit 130, thereby supplying the third drive force to the third drive source 50_3.

[0060] Thus, even when the multiple drive sources 50 have three or more drive sources, the correction unit 130 may be able to select which drive source to use as the reference for correcting the drive amount. That is, the drive device 100 sends the maximum current to each of the multiple drive sources 50 and checks the drive capacity of the multiple drive sources 50. If it is determined that the drive capacity of the first drive source 50_1 is the lowest, the correction unit 130 corrects the drive capacity of the second drive source 50_2 and the third drive source 50_3 using the first drive source 50_1 as the reference.

[0061] Therefore, in the third embodiment, the correction unit 130 requires multiple blocks corresponding to the multiple drive sources 50 to be corrected, and in the example above, two blocks are required: a block that corrects the drive capacity of the second drive source 50_2 and a block that corrects the drive capacity of the third drive source 50_3. Thus, in the third embodiment, the correction unit 130 has a first correction unit 130_1 and a second correction unit 130_2.

[0062] The first correction unit 130_1 corrects the drive amount calculated by the calculation unit 120 based on the detection position of the lens 30 and the tilt of the lens 30, in order to correct the drive capability of one of the multiple drive sources 50 to be corrected, in the example above, the second drive source 50_2. As an example, the first correction unit 130_1 corrects the drive current corresponding to the drive amount calculated by the calculation unit 120, for example, using the following formula: "Corrected drive current = drive current × coefficient 1 + drive current × detection position × coefficient 2". The first correction unit 130_1 outputs the corrected drive amount, which is the corrected drive amount, to the drive unit 140 corresponding to one of the multiple drive sources 50 to be corrected, in the example above, the second drive unit 140_2.

[0063] The second correction unit 130_2 corrects the drive amount calculated by the calculation unit 120 based on the detection position of the lens 30 and the tilt of the lens 30, in order to correct the drive capability of the other of the multiple drive sources 50 to be corrected, in the example above, the third drive source 50_3. For example, if a predetermined third coefficient is "coefficient 3" and a predetermined fourth coefficient is "coefficient 4", the second correction unit 130_2 corrects the drive current corresponding to the drive amount calculated by the calculation unit 120, for example, using the following formula: "Corrected drive current = drive current × coefficient 3 + drive current × detection position × coefficient 4". Here, at least one of "coefficient 3" and "coefficient 4" may also be predetermined to be a numerical value corresponding to the magnitude of the tilt of the lens 30, similar to "coefficient 1" and "coefficient 2". The second correction unit 130_2 outputs the corrected drive amount, which is the corrected drive amount, to the drive unit 140 corresponding to the other of the multiple drive sources 50 to be corrected, in the example above, to the third drive unit 140_3.

[0064] Even when moving the lens 30 using four or more drive sources, subblocks can be similarly added to the correction unit 130 and the multiple drive units 50. In this way, the drive device 100 according to the third embodiment corrects the driving capabilities of the multiple drive sources 50 to be corrected (for example, the second drive source 50_2 and the third drive source 50_3) based on one of the multiple drive sources 50 (for example, the first drive source 50_1). As a result, according to the drive device 100 according to the third embodiment, even when moving the lens 30 using three or more drive sources, the tilt of the lens 30 due to an imbalance in driving capabilities among the multiple drive sources 50 can be corrected according to the actually detected position of the lens 30.

[0065] Figure 5 shows an example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the fourth embodiment. In this figure, the same reference numerals are used for components having the same function and configuration as in Figure 4, and descriptions are omitted below except for differences. In the third embodiment, an example was shown in which the drive device 100 performs tilt correction processing based on the detected position of the lens 30 and the tilt of the lens 30. In the fourth embodiment, similar to the second embodiment, the drive device 100 performs tilt correction processing based on the target position of the lens 30 and the tilt of the lens 30.

[0066] The first correction unit 130_1 corrects the drive amount calculated by the calculation unit 120 based on the target position of the lens 30 and the tilt of the lens 30, in order to correct the drive capability of one of the multiple drive sources 50 to be corrected, in the example above, the second drive source 50_2. As an example, the first correction unit 130_1 corrects the drive current corresponding to the drive amount calculated by the calculation unit 120, for example, using the following formula: "Corrected drive current = drive current × coefficient 1 + drive current × target position × coefficient 2".

[0067] The second correction unit 130_2 corrects the drive amount calculated by the calculation unit 120 based on the target position of the lens 30 and the tilt of the lens 30, in order to correct the drive capability of the other of the multiple drive sources 50 to be corrected, in the example above, the third drive source 50_3. As an example, the second correction unit 130_2 corrects the drive current corresponding to the drive amount calculated by the calculation unit 120, for example, using the following formula: "Corrected drive current = drive current × coefficient 3 + drive current × target position × coefficient 4".

[0068] Thus, the drive device 100 according to the fourth embodiment corrects the drive amount based on a function of the target position rather than the detected position. As a result, according to the drive device 100 according to the fourth embodiment, even when the lens 30 is moved using three or more drive sources, the tilt of the lens 30 due to an imbalance in the drive capabilities among the multiple drive sources 50 can be corrected according to the target position of the lens 30 specified by the processor 70, rather than the actually detected position of the lens 30.

[0069] Figure 6 shows an example of a block diagram of the correction unit 130 in the drive device 100 according to the fifth embodiment. In the above embodiment, one example was shown in which at least one of the detection position or target position of the lens 30 is always used when correcting the drive amount. However, depending on the structure of the actuator (multiple drive sources 50), it may be preferable to perform the correction calculation without using the detection position or target position of the lens. Therefore, in the fifth embodiment, the correction unit 130 is configured to be switchable between using either the detection position or the target position for correcting the drive amount. The correction unit 130 has a switching unit 135.

[0070] The switching unit 135 switches the correction method for correcting the drive amount. For example, the correction unit 130 may be able to correct the drive amount using the following formula as correction method 1: "Corrected drive current = drive current × coefficient 1 + coefficient 2". Also, the correction unit 130 may be able to correct the drive amount using the following formula as correction method 2: "Corrected drive current = drive current × coefficient 1 + drive current × detected position or target position × coefficient 2".

[0071] In such cases, the switching unit 135 switches between correction method 1 and correction method 2, depending on the structure of the actuator, etc. Thus, in the fifth embodiment, the correction unit 130 may have a switching unit 135 that switches between correction using either the detected position or the target position (for example, correction method 2, i.e., correction using the formula "corrected drive current = drive current × coefficient 1 + drive current × detected position or target position × coefficient 2") and correction without using the detected position or target position (for example, correction method 1, i.e., correction using the formula "corrected drive current = drive current × coefficient 1 + coefficient 2"), depending on the characteristics of the first drive source 50_1 and the second drive source 50_2. As a result, the drive device 100 according to the fifth embodiment can select the optimal method according to the characteristics of the actuator to correct the drive amount.

[0072] Figure 7 shows an example of a block diagram of a camera module 10 which may be equipped with a drive device 100 according to the sixth embodiment. In this figure, the same reference numerals are used for components having the same function and configuration as in Figure 1, and descriptions are omitted below except for differences. In the above-described embodiment, an example was shown in which information indicating the tilt of the optical element is acquired in advance. In the sixth embodiment, the tilt of the optical element is detected each time during actual operation.

[0073] In the sixth embodiment, the camera module 10 further includes a tilt detector 60. The processor 70 is communicated with the tilt detector 60 via, for example, serial communication, parallel communication, a network, and wireless communication.

[0074] In this figure, the tilt detector 60 is shown as an example where it is located outside the drive unit 100, but the tilt detector 60 may also be built into the drive unit 100.

[0075] The tilt detector 60 detects the tilt of the optical element (lens 30). The tilt detector 60 supplies information indicating the detected tilt of the lens to the processor 70.

[0076] In the sixth embodiment, the correction unit 130 obtains information from the processor 70 indicating the tilt of the lens 30 detected by the tilt detector 60. The correction unit 130 may then correct the drive current using the following formula, which directly uses the tilt information: "Corrected drive current = drive current × coefficient 1' + tilt information × F (detection position)", where a predetermined coefficient is "coefficient 1'". Here, F (detection position) is a value that changes depending on the detection position. The correction unit 130 may, for example, perform tilt correction of the lens 30 by applying feedback so that the tilt of the lens detected during actual operation is below a predetermined threshold (preferably zero).

[0077] Although the present invention has been described above using embodiments, the technical scope of the present invention is not limited to the scope described in the above embodiments. It will be apparent to those skilled in the art that various modifications or improvements can be made to the above embodiments. It will be clear from the claims that such modified or improved forms may also be included in the technical scope of the present invention.

[0078] It should be noted that the execution order of operations, procedures, steps, and stages in the apparatus, systems, programs, and methods shown in the claims, specifications, and drawings is not explicitly stated as "before," "prior to," etc., and that these can be implemented in any order unless the output of a previous process is used in a later process. Even if the operation flow in the claims, specifications, and drawings is described using phrases such as "first," "next," etc. for convenience, it does not mean that it is essential to perform the operations in that order. [Explanation of Symbols]

[0079] 10 Camera Modules 20 Objects 30 lenses 40 magnets 40_1 The first magnet 40_2 The second magnet 50 Multiple power sources 50_1 First drive source 50_2 Second drive source 50_3 Third drive source 60 Tilt detector 70 processors 100 Drive unit 110 Position Sensor 120 Arithmetic section 130 Correction section 130_1 First Correction Unit 130_2 Second Correction Section 135 Switching section 140 Multiple drive units 140_1 First drive unit 140_2 Second drive unit 140_3 Third drive unit

Claims

1. A calculation unit that calculates the amount of drive of the optical element based on the detection position of the optical element and the target position of the optical element, A correction unit receives the drive amount, the detection position, and the target position as inputs, generates a corrected drive amount by correcting the drive amount based on the drive amount, a parameter corresponding to the tilt of the optical element, and either the detection position or the target position, and outputs the drive amount and the corrected drive amount. A first drive unit provides a first drive force corresponding to either the drive amount or the corrected drive amount to a first drive source among a plurality of drive sources for moving the optical element in a predetermined direction. A second drive unit that provides a second drive force corresponding to the other of the aforementioned drive amount and the aforementioned corrected drive amount to a second drive source among the plurality of drive sources, A drive device equipped with the following features.

2. The drive device according to claim 1, wherein the correction unit corrects the drive amount based on a function of the detected position.

3. If we define the predetermined first coefficient as "coefficient 1" and the predetermined second coefficient as "coefficient 2", The correction unit corrects the drive current corresponding to the drive amount calculated by the calculation unit using the formula "Corrected drive current = drive current × coefficient 1 + drive current × detection position × coefficient 2". The drive device according to claim 2.

4. The drive device according to claim 1, wherein the correction unit corrects the drive amount using a correction table that is defined in advance based on the detection position and the drive amount.

5. The drive device according to claim 1, wherein the correction unit corrects the drive amount based on a function of the target position.

6. If we define the predetermined first coefficient as "coefficient 1" and the predetermined second coefficient as "coefficient 2", The correction unit corrects the drive current corresponding to the drive amount calculated by the calculation unit using the formula "Corrected drive current = drive current × coefficient 1 + drive current × target position × coefficient 2". The drive device according to claim 5.

7. The drive device according to claim 1, wherein the correction unit corrects the drive amount using a correction table that is defined in advance based on the target position and the drive amount.

8. The drive device according to any one of claims 1 to 7, wherein the correction unit is configured to be switchable between using either the detection position or the target position for correcting the drive amount.

9. The drive device according to claim 8, wherein the correction unit has a switching unit that switches between correction using either the detection position or the target position and correction without using the detection position or the target position, depending on the characteristics of the first drive source and the second drive source.

10. The drive device according to any one of claims 1 to 7, wherein the correction unit selects which of the plurality of drive sources to use as a reference to correct the drive amount based on a parameter corresponding to the tilt of the optical element.

11. The drive device according to claim 10, wherein the parameter corresponding to the tilt indicates the tilt of the optical element detected when the maximum current is applied to each of the plurality of drive sources.

12. The drive device according to any one of claims 1 to 7, wherein the calculation unit calculates the drive amount by feedback control using the detected position and the target position.

13. A driving method for driving a plurality of drive sources, including a first drive source and a second drive source, Detecting the tilt of an optical element, To generate parameters corresponding to the tilt of the optical element, The system detects the position of the optical element and outputs the detected position. The amount of drive of the optical element is calculated based on the detection position of the optical element and the target position of the optical element. A corrected drive amount is generated by correcting the drive amount based on the drive amount, a parameter corresponding to the tilt of the optical element, and either the detection position or the target position. Based on a parameter corresponding to the tilt of the optical element, select which of the first and second drive sources to drive with a driving force corresponding to the corrected drive amount, A drive method equipped with

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