JP2014085629A - Control device and method for linear motion device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control device and method for a linear motion device capable of performing the accurate position control of the linear motion device even when the operating range of a lens is changed.SOLUTION: A device position command signal generation circuit 26 is configured to, on the basis of a target position signal value VTARG for designating a target position to which a linear motion device 31 should be moved, obtain a target position arithmetic signal value Vt_cal from a first position signal value NEG_VT corresponding to the designated home position of the linear motion device 31 and a second position signal value POS_VT corresponding to a designated full position. An A/D conversion circuit 23 is configured to obtain a detection position signal value VPROC. Driving currents are supplied to a drive coil 28 by a first output driver 27a and a second output driver 27b.

Description

  The present invention relates to a linear motion device control apparatus and control method thereof, and more particularly, to control of a linear motion device that enables accurate position control of the linear motion device even when the operating range of a lens is changed. The present invention relates to an apparatus and a control method thereof.

  Many of the camera modules installed in smart phones, which are multifunctional mobile phones that have high compatibility with general digital cameras, mobile phones, and the Internet and are based on the functions of personal computers, The function is installed. A contrast detection method is often adopted for an autofocus function mounted on such a compact camera. In this contrast detection method, the lens is actually moved to detect the lens position where the contrast of the subject in the captured image is maximized, and the lens is moved to that position.

  Such a contrast detection method can be realized at a lower cost compared to an active method in which the subject is irradiated with infrared rays or ultrasonic waves and the distance from the reflected wave to the subject is measured. However, there is a problem that it takes time to search for a lens position where the contrast of the subject is maximized. For this reason, it is desired that the process from when the user presses the shutter button halfway down until the subject is focused is completed within one second.

By the way, the number of pixels of camera modules mounted on general digital cameras and mobile phones is increasing year by year, and high-definition images can be taken even with these compact cameras. In high-definition images, focus shift is conspicuous, and more accurate autofocus control is required.
In general, a device in which an input signal and a displacement corresponding to the input signal are represented by a linear function is called a linear motion device. An example of this type of linear motion device is a camera autofocus lens.

  FIG. 1 is a configuration diagram for explaining a conventional linear motion device control apparatus. 1 includes a magnetic field sensor 13, a differential amplifier 14, a non-inverting output buffer 15, an inverting output buffer 16, a first output driver 17, and a second output driver 18. The controller of the linear motion device 12 shown in FIG. ing. The linear motion device 12 is feedback-controlled by a control device, and includes a lens 9 and a magnet 10.

  The magnetic field sensor 13 generates a signal based on the detected magnetic field and outputs it as an output signal SA. The output signal SA of the magnetic field sensor 13 and the device position command signal SB are input to the normal rotation input terminal and the reverse input terminal of the differential amplifier 14, respectively. From the differential amplifier 14 to which the output signal SA of the magnetic field sensor 13 and the device position command signal SB are input, an operation amount signal SC representing the operation amount (product of deviation and amplification degree) of the output drivers 17 and 18 is output. The

  The direction and amount of current flowing through the coil 11 of the linear motion device 12 vary depending on the magnitude of the manipulated variable signal SC. The position of the linear motion device 12 including the magnet 10 changes (moves) by the current flowing through the coil 11. At this time, the output signal SA of the magnetic field sensor 13 changes as the magnet 10 moves. The control device detects the position of the linear motion device 12 based on the change in the output signal SA, and performs feedback control so that this position matches the position indicated by the device position command signal SB input from the outside.

Here, it is often necessary to adjust the distance between the lens 9 and the image generated when the linear motion device 12 and the image sensor are assembled when the camera module is manufactured.
In general, the position of the end point on the image sensor side of the linear motion device 12 is configured to be operable, and when it is mechanically adjusted when combined with the image sensor or when the input range of the position command signal SB is limited. There are many. When performing mechanical adjustment, the linear motion device requires a structure for adjustment, leading to an increase in manufacturing cost. Further, when the input range of the position command signal SB is limited, there may be a case where the position control resolution becomes rough and accurate position control cannot be performed.

  As a method that does not require the above-described mechanical adjustment or limitation of the input range of the position command signal SB, there is a method as disclosed in Patent Document 1, for example. The method of Patent Document 1 relates to a focus control circuit that actually moves a lens to determine a focal position. The lens, a drive element for adjusting the position of the lens, and a position of the lens are detected. In a focus control circuit mounted on an imaging device including the position detection element, based on the difference between the lens position specified by the output signal of the position detection element and the target position of the lens set from the outside, An equalizer that generates a drive signal for adjusting the lens position to a target position and outputs the drive signal to the drive element, and an adjustment circuit for adjusting at least one of a gain and an offset of the position detection element are provided.

  By adjusting the gain and offset of the position detection element so that the movable range of the lens can be corrected, including manufacturing variations in the distance between the lens and the image sensor, the position command signal SB can be input without requiring mechanical adjustment. There is no need to limit the range.

JP 2011-22563 A

However, in the case of the method of adjusting the gain and offset of the position detection element as described in Patent Document 1 described above, the gain of the position detection element that has been optimally corrected by the linear motion device alone before being combined with the image sensor originally. And the offset will be readjusted.
FIG. 2 is a device (lens) response diagram when the change of the operating range of the lens is realized by adjusting the gain and offset of the position detection element. A solid line a is a device (lens) response when the lens operating range is Home to Full, and a dotted line b is a device (lens) response when the lens operating range is Home_cal to Full_cal. From FIG. 2, it can be seen that the lens operating range can be changed as shown by the dotted line b by changing the operating range of the lens by readjusting the gain and offset of the image sensor and the combination position detecting element. However, there may be a case where the position control characteristic obtained in the state where the linear motion device is corrected optimally cannot be obtained.

  The present invention has been made in view of such a problem, and the object of the present invention is not to be combined as an image sensor, but it is possible to adjust the gain and offset with a linear motion device alone. An object of the present invention is to provide a linear motion device control apparatus and a control method thereof capable of accurate position control without changing the response characteristics of the linear motion device even when the operating range is changed.

  The present invention has been made to achieve such an object. The invention according to claim 1 includes a linear motion device (31) having a magnet (32) attached to a moving body, and the linear motion device. And a drive coil (28) disposed in the vicinity of the magnet of the device, and a linear motion device for moving the lens (33) fixed to the magnet by a force generated by a coil current flowing through the drive coil A magnetic field sensor (21) for detecting a magnetic field generated by the magnet and outputting a detected position signal value (VPROC) corresponding to the detected magnetic field value; and a target for moving the linear motion device A device position command signal generation unit (25, 40) that outputs a target position signal value (VTARG) that indicates a position, and the detected position signal value (VP) by the magnetic field sensor OC) and a control unit (24) that generates a control signal for moving the lens (33) to the target position by PID control based on a target position signal value (VTARG) by the device position command signal generation unit. And an output driver (27a, 27b) for supplying a drive current to the drive coil based on the control signal by the control unit, and the target position signal value at the target position signal value even if the detected position signal value varies. It is possible to control the position of a linear motion device.

  According to a second aspect of the present invention, in the first aspect of the invention, the device position command signal generation unit (25, 40) stores a first stored value (POS_VT) of the target positions. A first storage device (401a), a second storage device (401b) for storing a second storage value (NEG_VT) of the target positions, the first storage value (POS_VT) and the second storage value A subtracter (402a) for subtracting a stored value (NEG_VT); a first adder (402b) for adding the first stored value (POS_VT) and the second stored value (NEG_VT); A first divider (403a) that divides the output value (POS_VT-NEG_VT) of the subtractor (402a) and the stored value of the third storage device (404a), and the output of the first adder (402b) Value (POS A second divider (403b) that divides VT + NEG_VT) and the stored value of the fourth storage device (404b); an initial target position signal value (Vt_ini); and an output signal of the first divider (403a) ( A multiplier (405) for multiplying (POS_VT + NEG_VT) / 512), an output signal (Vt_ini × ((POS_VT + NEG_VT) / 512)) of the multiplier (405), and an output signal of the second divider (403b) And a second adder (406) for adding ((POS_VT + NEG_VT) / 2).

According to a third aspect of the present invention, there is provided the selector according to the second aspect of the present invention, which selects the output (Vt_cal) of the second adder (406) and the initial target position signal value (Vt_ini). 407), and the selector is selected by a target position signal switching signal (CHAN) and is output as the target position signal value (VTARG).
The invention according to claim 4 is the invention according to claim 1, 2, or 3, wherein the magnetic field sensor is a Hall element.
The invention according to claim 5 is the invention according to any one of claims 11 to 4, wherein the linear motion device and the drive coil are incorporated in a camera module.

  The invention according to claim 6 includes a linear motion device having a magnet attached to a moving body, and a drive coil disposed in the vicinity of the magnet of the linear motion device, and a coil current is supplied to the drive coil. In the control method in the control device of the linear motion device that moves the lens fixed to the magnet by the force generated by the flowing of the magnetic field, first, the magnetic field generated by the magnet is detected by the magnetic field sensor, and the detected magnetic field A step of outputting a detected position signal value corresponding to the value of the signal, and then a target position signal value (VTARG) indicating a target position to which the linear motion device is to be moved by the device position command signal generation unit (25, 40). ), And then, by the control unit (24), the detected position signal value (VPROC) and the target position signal value (VTA). G) generating a control signal for moving the lens to the target position by PID control based on G), and then supplying a drive current to the drive coil based on the control signal by an output driver And the position of the linear motion device can be controlled with the target position signal value even if the detected position signal value varies.

  According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the step of outputting by the device position command signal generating unit (25, 40) includes the target position by the first storage device (401a). Storing a first stored value (POS_VT), storing a second stored value (NEG_VT) among the target positions by a second storage device (401b), and subtracting (402a) the first stored value. Subtracting one stored value (POS_VT) from the second stored value (NEG_VT), and the first stored value (POS_VT) and the second stored value (NEG_VT) by the first adder (402b). A step of adding, an output value (POS_VT-NEG_VT) of the subtractor (402a) by the first divider (403a) and a third storage device (404) ) And the output value (POS_VT + NEG_VT) of the first adder (402b) by the second divider (403b) and the stored value of the fourth storage device (404b). A step of multiplying an initial target position signal value (Vt_ini) by a multiplier (405) and an output signal ((POS_VT + NEG_VT) / 512) of the first divider (403a), a second adder (406) adding the output signal (Vt_ini × ((POS_VT + NEG_VT) / 512)) of the multiplier (405) and the output signal ((POS_VT + NEG_VT) / 2) of the second divider (403b); It is characterized by having.

  According to an eighth aspect of the present invention, in the seventh aspect of the invention, the output (Vt_cal) of the second adder (406) by the selector (407) and the initial target position signal value (Vt_ini) The selector is selected by a target position signal switching signal (CHAN) and is output as the target position signal value (VTARG).

  According to the present invention, the gain and offset can be adjusted by a linear motion device alone, not in a combined state as an image sensor, and the response characteristics of the linear motion device can be changed even when the operating range of the lens is changed. Therefore, it is possible to realize a linear motion device control apparatus and a control method thereof that enable accurate position control.

It is a block diagram for demonstrating the control apparatus of the conventional linear motion device. It is a device (lens) response diagram when the change of the operating range of the lens is realized by adjusting the gain and offset of the position detection element. It is a block diagram for demonstrating the control apparatus of the linear motion device which concerns on this invention. FIG. 4 is a specific configuration diagram of a device (lens) position command signal adjustment circuit shown in FIG. 3. It is a figure which shows the timing chart of the device (lens) position command signal adjustment circuit shown in FIG. It is a figure which shows that a target position signal value is set to 0 thru | or 511 also when the operating range of a lens is changed. It is a figure which shows the flowchart for demonstrating the control method of the linear motion device which concerns on this invention.

Embodiments of the present invention will be described below with reference to the drawings.
FIG. 3 is a block diagram for explaining a control apparatus for a linear motion device according to the present invention. In FIG. 3, the case where it applies to the control apparatus 20 which adjusts the position of the lens of the camera module 30 is demonstrated. The control device (position control circuit) 20 is configured as an IC circuit, for example. The camera module 30 includes a linear motion device 31 and a drive coil 28 that moves the lens 33. Therefore, by passing a current through the drive coil 28, the magnet 32 is moved, and the position of the lens 33 fixed to the magnet 32 can be adjusted.

  That is, the control device 20 of the linear motion device 31 includes a linear motion device 31 having a magnet 32 attached to a lens (moving body) 33, and a drive coil 28 disposed in the vicinity of the magnet 32 of the linear motion device 31. The magnet 32 is moved by the force generated by the coil current flowing through the drive coil 28.

The magnetic field sensor 21 detects a magnetic field generated by the magnet 32 and outputs a detected position signal value VPROC corresponding to the detected magnetic field value. That is, the magnetic field sensor 21 converts the magnetic field generated by the magnet 32 of the camera module 30 into an electrical signal and outputs the detection position signal to the amplifier 22. The amplifier 22 amplifies the detection position signal input from the magnetic field sensor 21. The magnetic field sensor 21 is preferably a Hall element.
The A / D conversion circuit 23 amplifies the detection position signal from the magnetic field sensor 21 by the amplifier 22 and performs A / D conversion, and obtains a detection position signal value VPROC subjected to A / D conversion.

  The device (lens) position command signal generation circuit 25 also includes an initial target position signal value Vt_ini that indicates a target position to which the linear motion device 31 should be moved, an upper limit position storage signal FULL of the lens 33 operating range, and a lens 33 operating range. The lower limit position storage signal HOME and the target position signal switching signal CHAN are output and are connected to the device (lens) position command signal adjustment circuit 40.

That is, the lens position command signal generation circuit 25 generates an initial target position signal value Vt_ini that is used to specify the target position of the lens 33, and to specify the upper limit POS_VT and the lower limit NEG_VT of the lens 33 operating range, and the initial target position signal value Vt_ini. Is stored as the upper limit POS_VT of the lens 33 operating range, and the lower limit position storing signal HOME is generated that stores the initial target position signal value Vt_ini as the lower limit NEG_VT of the lens 33 operating range.
Further, the position command signal adjustment circuit 40 is instructed to select the target position signal as the initial target position signal value Vt_ini and the target position signal value Vt_cal after the target position adjustment generated from the initial target position signal value Vt_ini. A target position switching signal CHAN is generated.

  The device (lens) position command signal adjustment circuit 40 outputs a target position signal value VTARG and is connected to the PID control circuit 24. The target position signal value VTARG is output as the target position signal value VTARG when the initial target position signal value Vt_ini is selected by the target position switching signal CHAN, and the target position signal value VTARG is set by the target position switching signal CHAN. When the target position signal value Vt_cal after position adjustment is selected, the target position signal value Vt_cal calculated from the initial target position signal value Vt_ini is output as the target position signal value VTARG.

  The PID control circuit 24 is connected to the A / D conversion circuit 23 and the device position command signal adjustment circuit 40, and receives the detected position signal value VPROC, which is an output signal from the A / D conversion circuit 23, as an input. Is to do. That is, the PID control circuit 24 inputs the detection position signal value VPROC from the A / D conversion circuit 23 and the target position signal value VTARG of the lens position generated by the device position command signal adjustment circuit 40, and the current of the lens 33 A control signal for moving the lens 33 to the target position is output from the position and the target position of the lens 33 indicated by the target position signal value VTARG.

  Here, the PID control is a kind of feedback control, and is a method of performing control of an input value by three elements of a deviation between an output value and a target value, its integration and differentiation. There is proportional control (P control) as basic feedback control. This controls the input value as a linear function of the deviation between the output value and the target value. In PID control, an operation for changing an input value in proportion to this deviation is referred to as a proportional operation or a P operation (P is an abbreviation for PROPORIONAL). In other words, if a state with a deviation continues for a long time, the change of the input value is increased and the role of trying to approach the target value is achieved. The operation of changing the input value in proportion to the integration of the deviation is referred to as an integration operation or an I operation (I is an abbreviation for INTERGRAL). A control method combining the proportional action and the integral action in this way is called PI control. The operation of changing the input value in proportion to the differential of the deviation is referred to as differential operation or D operation (D is an abbreviation for DERIVATIVE or DIFFERENTIAL). A control method combining a proportional action, an integral action, and a derivative action is called PID control.

  The output signal from the PID control circuit 24 is D / A converted by the D / A conversion circuit 26, and the detected position calculation signal value VPROC and the target position signal value VTARG by the first output driver 27a and the second output driver 27b. Based on the above, a drive current is supplied to the drive coil 28. That is, the first and second output drivers 27a and 27b generate the output signals Vout1 and Vout2 based on the control signal from the PID control circuit 24. The output signals Vout1 and Vout2 are supplied to both ends of the drive coil 28 of the camera module 30.

In the above description, the linear motion device is composed of the lens (moving body) 33 and the magnet 32 attached to the lens (moving body) 33. You can also
In this way, even when the operating range of the lens is changed, accurate position control can be performed without changing the response characteristic of the linear motion device.

  FIG. 4 is a specific configuration diagram of the device (lens) position command signal adjustment circuit shown in FIG. FIG. 5 is a timing chart of the device (lens) position command signal adjustment circuit shown in FIG. The device (lens) position command signal adjustment circuit 40 includes a first storage device (register / memory) 401a that stores an initial target position signal value Vt_ini as a storage value POS_VT when an upper limit position storage signal FULL is input from the outside. A second storage device (register / memory) 401b that stores the initial target position signal value Vt_ini as a stored value NEG_VT when an upper limit position storage signal HOME is input from the outside. Note that the storage value POS_VT of the first storage device 401a and the storage value NEG_VT of the second storage device 401b are not only stored as the initial target position signal value Vt_ini as a storage value by a position storage signal from the outside, but also from the outside. A method of specifying a value and inputting it is also possible.

  The device (lens) position command signal adjustment circuit 40 also includes a subtractor 402a that subtracts the stored value POS_VT of the first storage device 401a and the stored value NEG_VT of the second storage device 401b, and the first storage device 401a. The first adder 402b for adding the stored value POS_VT of the second storage device 401b and the stored value NEG_VT of the second storage device 401b, the output value (POS_VT-NEG_VT) of the subtractor 402a, and the stored value “512” of the third storage device 404a. , And a second divider 403b that divides the output value (POS_VT + NEG_VT) of the first adder 402b and the stored value “2” of the fourth storage device 404b. I have.

  The third storage device (register / memory) 404a is connected to the divider 403a and stores “512”. This “512” is arbitrarily changed depending on the settable range of the initial target position signal value Vt_ini. The fourth storage device (register / memory) 404b is connected to the divider 403b and stores “2”.

The device (lens) position command signal adjustment circuit 40 includes a multiplier 405 that multiplies the initial target position signal value Vt_ini by the output signal ((POS_VT + NEG_VT) / 512) of the first divider 403a. The output signal (Vt_ini × ((POS_VT + NEG_VT) / 512)) of the multiplier 405 is added to the output signal ((POS_VT + NEG_VT) / 2) of the second divider 403b via the second adder 406.
Vt_cal = Vt_ini × ((POS_VT + NEG_VT) / 512)) + ((POS_VT + NEG_VT) / 2) is obtained. Further, the selector 407 for selecting the output Vt_cal of the second adder 406 and the initial target position signal value Vt_ini is selected by the target position signal switching signal CHAN and is output as the target position signal value VTARG.

  FIG. 6 is a diagram showing that the target position signal value VTARG becomes 0 to 511 even when the operating range of the lens is changed to the NEG_VT to POS_VT range. In FIG. 6, the first vertical axis from the left indicates a magnetic field detected by the magnetic field sensor 21 (hereinafter also referred to as a detected magnetic field), and the second vertical axis from the left indicates A / D conversion. The digital value of the magnetic field signal converted by the circuit 23 is shown, the first vertical axis from the right in the figure shows the initial target position signal value Vt_ini of the linear motion device 31, and the second vertical axis from the right in the figure. The target position signal value Vt_cal after target position adjustment calculated by the device position command signal adjustment circuit 40 from the initial target position signal value Vt_ini is shown as the target position signal value VTARG. Further, the horizontal axis of FIG. 6 is the position of the linear motion device 31. As is apparent from FIG. 6, if the upper limit POS_VT and the lower limit NEG_VT of the lens 33 operating range are designated, the resolution of the target position signal value VTARG from 0 to 511 is maintained, and a linear motion can be obtained.

In this way, even when the operating range of the lens is changed, it is possible to realize a linear motion device control apparatus that can accurately control the position of the linear motion device with a single linear motion device.
FIG. 7 is a diagram illustrating a flowchart for explaining the control method of the linear motion device according to the present invention.

  The control method in the control apparatus 20 of the linear motion device 31 of the present invention includes a linear motion device 31 having a magnet 32 attached to a moving body 33, and a drive coil 28 disposed in the vicinity of the magnet 32 of the linear motion device 31. And the lens fixed to the magnet 32 is moved by the force generated by the coil current flowing through the drive coil 28.

  First, the magnetic field sensor 21 detects the magnetic field generated by the magnet 32 and outputs a detected position signal value VPROC corresponding to the detected magnetic field value (S1), and then to the device position command signal generation circuit. Based on the input initial target position signal value Vt_ini, the stored value POS_VT of the first storage device 401 a corresponding to the upper limit position of the linear motion device 31 and the second storage corresponding to the lower limit position of the linear motion device 31. The step (S2) of acquiring the storage value NEG_VT of the device 401b, and then calculating the target position calculation signal value Vt_cal from the storage value POS_VT of the first storage device 401a and the storage value NEG_VT of the second storage device 401b, The step (S3) of obtaining the target position calculation signal value VTARG and then the detected position by the output drivers 27a and 27b. A step (S4) of supplying a drive current to the drive coil 28 based on the signal value VPROC and the target position signal value VTARG, and even if the operating range of the lens is changed, the target position signal value VTARG is linear. Allows position control of the exercise device. In addition, when repeating position control continuously, step S3 thru | or S4 are repeated.

  Further, the control method of the linear motion device according to the present invention will be described in detail. The step of outputting by the device position command signal generation units 25 and 40 includes the first stored value POS_VT in the target position by the first storage device 401a. A step of storing; a step of storing the second stored value NEG_VT among the target positions by the second storage device 401b; a step of subtracting the first stored value POS_VT and the second stored value NEG_VT by the subtractor 402a; A step of adding the first stored value POS_VT by the first adder 402b and the second stored value NEG_VT, an output value POS_VT-NEG_VT of the subtractor 402a by the first divider 403a, and a stored value of the third storage device 404a. And the output of the first adder 402b by the second divider 403b Dividing the POS_VT + NEG_VT by the stored value of the fourth storage device 404b, and multiplying the initial target position signal value Vt_ini by the multiplier 405 and the output signal (POS_VT + NEG_VT) / 512 of the first divider 403a; The output signal Vt_ini × ((POS_VT + NEG_VT) / 512) of the multiplier 405 by the second adder 406 and the output signal (POS_VT + NEG_VT) / 2 of the second divider 403b are added.

The selector 407 further includes a step of selecting an output Vt_cal of the second adder 406 and an initial target position signal value Vt_ini. The selector is selected by the target position signal switching signal CHAN and is output as a target position signal value VTARG. Is done.
In this way, according to the present invention, it is possible to realize a linear motion device control method that enables accurate position control of the linear motion device with a single linear motion device even when the operating range of the lens is changed. .

9 Lens 10 Magnet 11 Coil 12 Linear motion device 13 Magnetic field sensor 14 Differential amplifier 15 Non-inverted output buffer 16 Inverted output buffer 17 First output driver 18 Second output driver 20 Controller 21 Magnetic field sensor 22 Amplifier 23 A / D Conversion circuit 24 PID control circuit 25 Device (lens) position command signal generation circuit 26 D / A conversion circuit 27a First output driver 27b Second output driver 28 Driving coil 30 Camera module 31 Linear motion device 32 Magnet 33 Lens (movement) body)
40 Device (lens) position command signal adjustment circuit 401a First storage device (register / memory)
401b Second storage device (register / memory)
402a Subtractor 402b First adder 403a First divider 403b Second divider 404a Third storage device (register / memory)
404b Fourth storage device (register / memory)
405 multiplier 406 second adder 407 selector

Claims (8)

A linear motion device having a magnet attached to a moving body, and a drive coil disposed in the vicinity of the magnet of the linear motion device, and a force generated by a coil current flowing through the drive coil. In a control device for a linear motion device that moves a fixed lens,
A magnetic field sensor that detects a magnetic field generated by the magnet and outputs a detected position signal value corresponding to the detected magnetic field value;
A device position command signal generating unit for outputting a target position signal value indicating a target position to move the linear motion device;
A control unit that generates a control signal for moving the lens to the target position by PID control based on the detection position signal value by the magnetic field sensor and the target position signal value by the device position command signal generation unit;
An output driver for supplying a drive current to the drive coil based on the control signal by the control unit,
An apparatus for controlling a linear motion device, which enables position control of the linear motion device with the target position signal value even if the detected position signal value varies. The device position command signal generator is
A first storage device for storing a first stored value among the target positions;
A second storage device for storing a second stored value among the target positions;
A subtractor for subtracting the first stored value and the second stored value;
A first adder for adding the first stored value and the second stored value;
A first divider for dividing the output value of the subtractor from the stored value of the third storage device;
A second divider for dividing the output value of the first adder from the stored value of the fourth storage device;
A multiplier for multiplying an initial target position signal value by an output signal of the first divider;
The linear motion device control apparatus according to claim 1, further comprising: a second adder that adds the output signal of the multiplier and the output signal of the second divider.   A selector for selecting an output of the second adder and the initial target position signal value is provided, and the selector is selected by a target position signal switching signal and output as the target position signal value. Item 3. The control device for the linear motion device according to Item 2.   The linear motion device control apparatus according to claim 1, wherein the magnetic field sensor is a Hall element.   The linear motion device control apparatus according to any one of claims 1 to 4, wherein the linear motion device and the drive coil are incorporated in a camera module. A linear motion device having a magnet attached to a moving body, and a drive coil disposed in the vicinity of the magnet of the linear motion device, and a force generated by a coil current flowing through the drive coil. In a control method in a control device of a linear motion device that moves a fixed lens,
First, a magnetic field sensor detects a magnetic field generated by the magnet, and outputs a detected position signal value corresponding to the detected magnetic field value;
Next, outputting a target position signal value indicating a target position to which the linear motion device is to be moved by the device position command signal generation unit;
Next, a control unit generates a control signal for moving the lens to the target position by PID control based on the detected position signal value and the target position signal value;
Next, a step of supplying a drive current to the drive coil based on the control signal by an output driver,
A method for controlling a linear motion device, wherein the position of the linear motion device can be controlled with the target position signal value even if the detected position signal value varies. The step of outputting by the device position command signal generation unit,
Storing a first stored value among the target positions by the first storage device;
Storing a second stored value among the target positions by the second storage device;
Subtracting the first stored value and the second stored value by a subtractor;
Adding the first stored value and the second stored value by a first adder;
Dividing the output value of the subtractor by the first divider from the stored value of the third storage device;
Dividing the output value of the first adder by the second divider from the stored value of the fourth storage device;
Multiplying the initial target position signal value by the multiplier by the output signal of the first divider;
The method for controlling a linear motion device according to claim 6, further comprising: adding an output signal of the multiplier and an output signal of the second divider by a second adder. Selecting the output of the second adder by the selector and the initial target position signal value;
8. The method of controlling a linear motion device according to claim 7, wherein the selector is selected by a target position signal switching signal and output as the target position signal value.

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