KR102169957B1 - Camera module and method for auto focus thereof - Google Patents

Abstract

A camera module including a voice coil motor actuator and an autofocus method thereof, comprising: a fixing part in which a through hole is formed, a magnet disposed on an inner surface of the through hole of the fixing part, and at least one lens, and the fixing part A moving part linearly moving within the through hole, a moving coil surrounding the outer surface of the moving part, and a fixed coil disposed in the fixed part to receive a current or voltage varying according to a distance from the moving coil from the moving coil. . In addition, the present invention may further include a detection unit for detecting a displacement value of a current or voltage received from the fixed coil, an image sensor sensing an image incident through a lens of the moving unit, and an image signal sensed from the image sensor An image signal processing unit that processes an image signal processing unit, a focus position calculation unit that calculates an optimal focus and focus position value based on the displacement value of the current or voltage received from the fixed coil, and the moving unit moves to the calculated optimal focus position value. It may further include a control unit for controlling.

Description

Camera module and its auto focus method {CAMERA MODULE AND METHOD FOR AUTO FOCUS THEREOF}

The present invention relates to a camera module, and more particularly, to a camera module including a voice coil motor actuator and an autofocus method thereof.

With the recent development of technology, multi-function mobile terminals in which various functions are integrated at a high density are being released, and despite the complex and diversified functions, mobile terminals tend to be miniaturized and lightweight to suit a mobile environment.

Accordingly, camera modules mounted on mobile terminals such as mobile phones and notebook computers are also being miniaturized due to the trend of miniaturization and high precision of lenses.

In the optical system of the camera module, an auto focus function is required to clearly see a target object as a subject.

Such an auto focus function uses various types of actuators to move the lens module to an optimal focus position, and the autofocus performance of the camera module may vary depending on the characteristics of the actuator that transports the lens module. .

In addition, the auto focus actuator may include various types of actuators such as a voice coil motor (VCM) actuator, an actuator driven by piezoelectric power, and a MEMS actuator driven by a capacitance method. .

Here, in the actuator of the voice coil motor type, a permanent magnet is placed in a fixed part of the camera module, a coil is attached to the lens module to be driven, and a magnetic circuit is formed, thereby driving the lens module by Lorentz force flowing through the coil. This is the way to do it.

In addition, in the voice coil actuator, by attaching a sensor to the lens module and extracting a difference in a magnetic flux value according to the displacement of the lens module, the optimum auto focus value of the lens module can be calculated.

In such an actuator of the voice coil type, in order to attach the sensor to the lens module, three power sources must be connected to the sensor, so that the manufacturing process is difficult.

In other words, the voice coil actuator has at least 5 connectors including 2 connectors for electrical connection with the coil located in the lens module and 3 connectors for electrical connection with the sensor located in the lens module. Because it should be, not only is it difficult to design, but there are many difficulties in the manufacturing process.

In addition, the voice coil type actuator using a sensor-attached lens module takes a long time to move the lens module to the optimum position of autofocus, and the autofocus position of the lens module due to hysteresis and structural friction characteristics. An error could have occurred.

The technical problem to be achieved by an embodiment of the present invention is to arrange a fixed coil in a fixed part, a moving coil in a moving part, and detect a displacement value of a current or voltage according to a distance between the fixed coil and the moving coil, It is intended to provide a camera module capable of quickly and accurately finding an auto focus position and an auto focus method thereof.

In addition, the technical problem to be achieved by an embodiment of the present invention is to provide a camera module capable of reducing natural vibration of the spring and an autofocus method thereof by arranging a damper between a spring and a fixing part.

A camera module according to an embodiment of the present invention includes a fixing part in which a through hole is formed, a magnet disposed on an inner surface of the through hole of the fixing part, and at least one lens, and linearly moves within the through hole of the fixing part. It may include a moving unit, a moving coil surrounding an outer surface of the moving unit, and a fixed coil disposed on the fixed unit to receive a current or voltage varying according to a distance from the moving coil from the moving coil.

Here, the fixed coil may be disposed at a predetermined interval from one side of the moving unit and positioned on a moving direction line of the moving unit.

In addition, the moving coil may receive a driving signal in which a high-frequency signal is loaded on a low-frequency signal and transmit the driving signal to the fixed coil.

In addition, the present invention may further include a spring connected between the fixed part and the moving part to provide an elastic force according to the movement of the moving part.

Here, between the spring and the fixing part, a damper may be disposed.

In addition, the present invention may further include a detection unit that detects a displacement value of a current or voltage received from the fixed coil.

Here, the detection unit includes a half-wave rectifying unit that rectifies a frequency signal for a current or voltage received from the fixed coil into a half-wave signal, a conversion unit that converts the half-wave signal received from the half-wave rectifier into current or voltage, and the conversion unit It may include an amplifier for amplifying a frequency signal for current or voltage, and a peak detector for detecting a peak of the frequency signal amplified from the amplifier.

In addition, the present invention is based on an image sensor for sensing an image incident through a lens of a moving unit, an image signal processing unit for processing an image signal sensed from the image sensor, and a displacement value of the current or voltage received from the fixed coil. , A focus position calculating unit that calculates an optimal focus and focus position value, and a control unit that controls movement of the moving unit with the calculated optimal focus position value.

Next, the autofocus method of the camera module according to the present invention includes the steps of applying a driving signal to the moving coil to move the moving unit, sensing an image incident through the lens of the moving unit according to the movement of the moving unit, and sensing the moving coil. Detecting a displacement value of a current or voltage according to the distance between the fixed coil and the fixed coil; processing the sensed image signal; and calculating an optimal focus position value from the processed image signal and the detected displacement value of the current or voltage. It may include calculating and moving the moving unit to the calculated optimal focus position value.

According to an embodiment of the present invention, a fixed coil is disposed in a fixed part, a moving coil is disposed in a moving part, and a displacement value of a current or voltage according to a distance between the fixed coil and the moving coil is detected, and the auto focus position It has the effect of finding quickly and accurately.

In addition, according to the present invention, by disposing a damper between the spring and the fixing portion, the natural vibration of the spring is reduced, thereby preventing an error in auto focus and reducing the auto focus time.

1 is a view showing the configuration of a camera module according to the present invention
2 is a circuit diagram showing a detection unit of a camera module according to the present invention
3 is a view for explaining an electromagnetic induction phenomenon between the fixed coil and the moving coil of FIG. 1
Figure 4 is a plan view showing the spring of Figure 1
5 is a graph showing natural vibration frequency characteristics before and after applying a damper of a spring
6 is a block diagram showing an auto focusing control unit of a camera module according to the present invention
7 and 8 are flowcharts illustrating an autofocus method of a camera module according to the present invention

Hereinafter, the present invention will be described in more detail with reference to the drawings.

The suffixes "module" and "unit" for the constituent elements used in the following description are simply given in consideration of ease of writing in the present specification, and the "module" and "unit" may be used interchangeably with each other.

Further, embodiments of the present invention will be described in detail with reference to the accompanying drawings and contents described in the accompanying drawings, but the present invention is not limited or limited by the embodiments.

The terms used in the present specification have selected general terms that are currently widely used as possible while considering functions in the present invention, but this may vary according to the intention or custom of a technician working in the art, or the emergence of new technologies. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning will be described in the description of the corresponding invention. Therefore, it should be noted that terms used in the present specification should be interpreted based on the actual meaning of the term and the entire contents of the present specification, not a simple name of the term.

The camera module described in this specification may be included in a mobile phone, a smart phone, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, and the like.

However, it will be readily apparent to those skilled in the art that the configuration of the camera module according to the embodiment described in the present specification may be applied to fixed terminals such as digital TVs and desktop computers, except when applicable only to mobile terminals. will be.

1 is a cross-sectional view showing the configuration of a camera module according to the present invention.

As shown in FIG. 1, the camera module of the present invention includes a fixed part 100 in which a magnet 110 and a fixed coil 120 are disposed, and a moving part in which a lens 210 and a moving coil 220 are disposed. It may include (200).

Here, the fixing part 100 may have a through hole formed in a central region.

In this case, the magnet 110 may be disposed on the inner side of the through hole of the fixing part 100.

As an example, the number of magnets 110 may be one, or in some cases, a plurality of magnets 110 may be used.

When there are a plurality of magnets 110, the plurality of magnets 110 may be disposed at the same distance from each other, but in some cases, they may be disposed at different distances.

In addition, the plurality of magnets 110 may be disposed symmetrically with respect to the coordinate axis passing through the center of the through hole of the fixing part 100.

Here, the reason that the plurality of magnets 110 are arranged symmetrically with respect to the coordinate axis passing through the center of the through hole of the fixing part 100 is that the displacement value of the current or voltage according to the movement of the moving part 200 which is a lens module This is because it can be detected stably without external influence.

Further, the moving part 200 includes at least one lens 210 and may linearly move within the through hole of the fixing part 100.

Here, the moving unit 200 may be a lens module including lenses 210.

Subsequently, the moving coil 220 may be disposed to surround the outer surface of the moving unit 200 and may be moved together with the moving unit 200.

Here, the moving coil 220 and the magnet 110 are actuators for moving the moving unit 200, so that the moving unit 200 moves linearly in the upper and lower directions, the moving unit 200 Can be driven.

Next, the fixed coil 120 may be disposed on the fixed part 100 to receive a current or voltage that varies according to a distance from the moving coil 220 from the moving coil 220.

Here, the fixed coil 120 is disposed at a predetermined interval from one side of the moving unit 100 and may be positioned on a line in the moving direction of the moving unit 100.

Accordingly, in the fixed coil 120 and the moving coil 220, current or voltage may be induced from the moving coil 220 to the fixed coil 120 by an electromagnetic mutual induction phenomenon.

In this case, the induced current or voltage value may vary according to the distance between the fixed coil 120 and the moving coil 220.

That is, the current or voltage value induced in the fixed coil 120 changes according to the vertical distance between the fixed coil 120 and the moving coil 220, and using this displacement value, the lens of the moving part 200 The position value of the module can be predicted.

And, using the predicted position value of the lens module, to find the optimum auto focus position value, and to control the movement of the moving unit 200 so as to move the actual position value of the lens module to the optimal auto focus position value. I can.

In addition, the number of turns of the fixed coil 120 and the number of turns of the moving coil 220 may be different from each other.

For example, the number of turns of the fixed coil 120 may be smaller than the number of turns of the moving coil 220.

Here, the reason that the number of turns of the fixed coil 120 is less than the number of turns of the moving coil 220 is that the size of the overall camera module can be reduced, and the frequency signal for the current or voltage induced in the fixed coil 120 This is because it can amplify.

In some cases, the number of turns of the fixed coil 120 and the number of turns of the moving coil 220 may be the same.

Further, the moving coil 220 may receive a driving signal in which a high-frequency signal is loaded on a low-frequency signal and transmit the driving signal to the fixed coil 120.

That is, the driving signal applied to the moving coil 220 of the moving unit 200 may be a signal in which an arbitrary high-frequency signal is loaded on a low-frequency driving signal.

Accordingly, the fixed coil 120 receives a frequency signal for a current or voltage induced from the moving coil 220 due to an electromagnetic induction phenomenon, and the received frequency signal may be a signal in which a high frequency signal is loaded on a low frequency signal. .

Here, the reason why the driving signal in which the high-frequency signal is loaded on the low-frequency signal is applied to the moving coil 220 is by increasing the frequency signal for the current or voltage induced in the fixed coil 120 due to the electromagnetic induction phenomenon, This is because the voltage displacement value can be easily detected.

In addition, the camera module of the present invention may include a spring 350 that is connected between the fixing unit 100 and the moving unit 200 to provide an elastic force according to the movement of the moving unit 200.

In addition, a damper (not shown) may be disposed between the spring 350 and the fixing part 100.

Here, the damper may be disposed adjacent to the connection end of the spring 350 and the fixing part 100.

At this time, the reason for forming the damper is to suppress the natural vibration of the spring 350, and by reducing the hysteresis characteristic, an error of auto focus can be prevented.

In addition, the camera module of the present invention may include a detection unit (not shown) that detects a displacement value of a current or voltage received from the fixed coil 120.

Here, the detection unit includes a half-wave rectifying unit that rectifies a frequency signal for a current or voltage received from the fixed coil into a half-wave signal, a conversion unit that converts the half-wave signal received from the half-wave rectifier into current or voltage, and the conversion unit It may include an amplifier for amplifying a frequency signal for current or voltage, and a peak detector for detecting a peak of the frequency signal amplified from the amplifier.

In addition, the camera module of the present invention may further include an auto-focusing control unit that controls auto-focusing of the moving unit 200, which is a lens module, wherein the auto-focusing control unit includes an image sensor 510, an image signal processing unit, and a focus position. It may further include a calculation unit and a driving control unit.

Here, the image sensor 510 may sense an image incident through the lens 210 of the moving unit 200.

In addition, the image signal processor (not shown) may process the image signal sensed from the image sensor 510.

Next, the focus position calculation unit (not shown) calculates the optimum focus position value based on the image signal processed from the image signal processing unit and the displacement value of the current or voltage received from the fixed coil disposed in the fixed unit. I can.

Subsequently, the driving control unit (not shown) may control the movement of the moving unit using the calculated optimal focus position value.

In this way, the camera module according to the present invention arranges a fixed coil on a fixed part, a moving coil on a moving part, and detects a displacement value of current or voltage according to the distance between the fixed coil and the moving coil, The focus position can be found quickly and accurately.

In addition, according to the present invention, by disposing a damper between the spring and the fixing part, the natural vibration of the spring is reduced, so that an error of auto focus can be prevented and the auto focus time can be reduced.

2 is a circuit diagram showing a detection unit of a camera module according to the present invention.

As shown in Figure 2, the camera module of the present invention, a permanent magnet 110 is disposed on the fixed part 100, and the moving coil 220 is disposed on the moving part 200, constituting a magnetic circuit. , This is a method in which the moving part 200, which is a lens module, is driven by the Lorentz force of the current flowing through the coil.

In addition, the fixed coil 120 may be disposed on the fixed part 100 to receive a current or voltage that varies according to a distance from the moving coil 220 from the moving coil 220.

Here, the fixed coil 120 is disposed at a predetermined interval from one side of the moving unit 100 and may be positioned on a line in the moving direction of the moving unit 100.

Accordingly, in the fixed coil 120 and the moving coil 220, current or voltage may be induced from the moving coil 220 to the fixed coil 120 by an electromagnetic mutual induction phenomenon.

In this case, the induced current or voltage value may vary according to the distance between the fixed coil 120 and the moving coil 220.

That is, the current or voltage value induced in the fixed coil 120 changes according to the vertical distance between the fixed coil 120 and the moving coil 220, and using this displacement value, the lens of the moving part 200 The position value of the module can be predicted.

Therefore, the detection unit 400 may detect a displacement value of the current or voltage received from the fixed coil 120.

Here, the detection unit 400 may include a half-wave rectification unit 422, a conversion unit 424, an amplification unit 426, and a peak detection unit 428, but is not limited thereto.

First, the half-wave rectifying unit 422 of the detection unit 400 may rectify a frequency signal for a current or voltage received from the fixed coil 120 into a half-wave signal.

In addition, the conversion unit 424 of the detection unit 400 may convert a half-wave signal received from the half-wave rectifier 422 into a current or voltage.

Subsequently, the amplification unit 426 of the detection unit 400 may amplify a frequency signal for the current or voltage converted from the conversion unit 424.

Next, the peak detection unit 428 of the detection unit 400 may detect the peak of the frequency signal amplified from the amplification unit 426.

For example, when a current is induced in the fixed coil 120, the half-wave rectifier 422 rectifies a frequency signal for the induced current into a half-wave signal.

Further, the conversion unit 424 is a current-voltage conversion circuit for converting a current into a voltage, and converts a current rectified by a half-wave signal into a voltage.

Subsequently, the amplification unit 426 amplifies the converted voltage.

Next, the peak detector 428 may detect the peak value of the amplified voltage and output the detected peak value.

In this way, the detection unit 400 detects a displacement value of the current or voltage received from the fixed coil 120, and the autofocusing control unit for controlling the autofocusing of the moving unit 200, which is a lens module, determines the displacement value. Using this, the position value of the lens module of the moving unit 200 may be predicted.

Then, the auto-focusing control unit uses the predicted position value of the lens module to find an optimal auto-focus position value, and moves the actual position value of the lens module to the optimal auto-focus position value. Can control its movement.

3 is a view for explaining an electromagnetic induction phenomenon between the fixed coil and the moving coil of FIG. 1.

As illustrated in FIG. 3, the moving coil of the camera module 10 may receive a driving signal in which a high frequency signal is loaded on a low frequency signal and transmit the driving signal to the fixed coil.

That is, the driving signal applied to the moving coil of the moving unit may be a signal in which an arbitrary high-frequency signal is loaded on a driving signal of a low frequency.

Accordingly, the fixed coil receives a frequency signal for a current or voltage induced from the moving coil by an electromagnetic induction phenomenon, and the received frequency signal may be a signal in which a high frequency signal is loaded on a low frequency signal.

Here, the electromagnetic induction high-frequency response signal received by the fixed coil decreases as the distance between the fixed coil and the moving coil increases, and increases as the distance between the fixed coil and the moving coil increases.

As described above, according to the distance between the fixed coil and the moving coil, the electromagnetic induction high-frequency response signal received by the fixed coil varies, so the detection unit detects a displacement value of the current or voltage received by the fixed coil, and the autofocusing control unit, Using this displacement value, the position value of the lens module of the moving unit 200 can be predicted.

In addition, the auto-focusing control unit controls the movement of the moving unit to find the optimal auto-focus position value using the predicted position value of the lens module and to move the actual position value of the lens module to the optimal auto-focus position value. can do.

4 is a plan view showing the spring of FIG. 1.

As shown in FIG. 4, the spring 350 may be connected between the fixed part 100 and the moving part 200 to provide an elastic force according to the movement of the moving part 200.

Here, the spring 350 may include a first connection part 350a connected to the moving part 200 and a second connection part 350b connected to the fixing part 100.

In general, the spring 350 has a natural frequency, and due to the natural frequency of the spring, the moving unit 200 may cause a loss of time to wait for a predetermined time to stabilize after moving.

Therefore, by disposing a damper 360 between the spring 350 and the fixing part 100, it is possible to suppress the natural vibration of the spring.

Here, the position of the damper 360 may be disposed in all areas between the spring 350 and the fixing part 100.

For example, the damper 360 may be disposed adjacent to the second connection part 350b connecting the spring 350 and the fixing part 100.

Therefore, by forming a damper between the spring 350 and the fixing part 100, the natural vibration of the spring 350 is suppressed and the hysteresis characteristic is reduced, thereby preventing an error of auto focus, Auto focus time can be shortened.

5 is a graph showing natural vibration frequency characteristics before and after application of a damper of a spring.

As shown in FIG. 5, when a damper is not applied to the spring, since it takes a long time after the moving unit moves and until the moving unit stabilizes, unnecessary time loss may occur.

However, if a damper is applied to the spring, after the moving unit moves, the moving unit is stabilized within a very short time, and thus unnecessary time loss waiting for the moving unit to stabilize can be eliminated.

Accordingly, according to the present invention, by applying a damper to the spring, the natural vibration of the spring is suppressed and the hysteresis characteristic is reduced, thereby preventing an error in auto focus and reducing the auto focus time.

6 is a block diagram showing an auto focusing control unit of a camera module according to the present invention.

As shown in FIG. 6, the camera module of the present invention may further include an auto-focusing control unit that controls auto-focusing of a moving unit, which is a lens module. The auto-focusing control unit includes an image sensor 510 and an image signal processing unit ( 520), a focus position calculating unit 530, and a driving control unit 540 may be further included.

Here, the image sensor 510 senses an image of a subject incident through the lens of the moving part, which is connected to the fixing part by a spring 350 and is moved by auto-focusing.

In addition, the image signal processing unit 520 processes the image signal sensed by the image sensor 510.

Next, the focus position calculation unit 530 receives the image signal processed from the image signal processing unit 520 and the displacement value of the current or voltage according to the distance between the moving coil and the fixed coil detected by the detection unit 400. , It is possible to calculate an optimal focus position value.

Next, the driving control unit 540 may control the driving unit so that the moving unit moves to the calculated optimal focus position value.

7 and 8 are flowcharts illustrating an autofocus method of a camera module according to the present invention.

7 and 8, the driving control unit moves the moving unit for auto focus. (S10)

Here, a driving signal is applied to the moving coil, and the driving signal applied to the moving coil may be a driving signal in which a high frequency signal is loaded on a low frequency signal.

Subsequently, the image sensor senses an image incident through the lens of the moving unit, and the detection unit detects a displacement value of a current or voltage according to a distance between the moving coil and the fixed coil from the fixed coil (S20).

Here, in the step of detecting the displacement value of the current or voltage according to the distance between the moving coil and the fixed coil, the half-wave rectifying unit of the detecting unit rectifies the frequency signal for the current or voltage received from the fixed coil into a half-wave signal. S22)

Then, the conversion unit of the detection unit converts the rectified half-wave signal into current or voltage (S24), and then the amplification unit of the detection unit amplifies a frequency signal corresponding to the converted current or voltage (S26).

Subsequently, the peak detection unit of the detection unit may detect and output the peak of the amplified frequency signal to detect the displacement value of the current or voltage (S28)

Next, the image signal processor processes the image signal sensed from the image sensor (S30).

The focus position calculating unit calculates an optimum focus position value by receiving an image signal processed from the image signal processing unit and a displacement value of a current or voltage according to a distance between the moving coil and the fixed coil detected by the detection unit (S40). )

Subsequently, the driving control unit may move the moving unit to the calculated optimal focus position value to perform autofocus (S50).

In this way, the camera module according to the present invention arranges a fixed coil on a fixed part, a moving coil on a moving part, and detects a displacement value of current or voltage according to the distance between the fixed coil and the moving coil, The focus position can be found quickly and accurately

In addition, according to the present invention, by disposing a damper between the spring and the fixing part, the natural vibration of the spring is reduced, so that an error of auto focus can be prevented and the auto focus time can be reduced.

In the above, preferred embodiments of the present invention have been illustrated and described, but the present invention is not limited to the specific embodiments described above, and is generally used in the technical field to which the present invention belongs without departing from the gist of the present invention claimed in the claims. Of course, various modifications may be implemented by those skilled in the art, and these modifications should not be understood individually from the technical spirit or prospect of the present invention.

100: fixed part 110: magnet
120: fixed coil 200: moving part
210: lens 220: moving coil
350: spring 400: detection unit

Claims (14)

A fixing part in which a through hole is formed;
A magnet disposed on an inner surface of the through hole of the fixing part;
A moving part including at least one lens and linearly moving within the through hole of the fixing part;
A moving coil surrounding the outer surface of the moving part-the moving part is moved by a Lorentz force generated between the magnet and the moving coil as a driving signal loaded with a high frequency signal in a low frequency signal is applied to the moving coil;
A fixed coil disposed on the fixed part to generate a current or voltage according to an electromagnetic induction phenomenon with the moving coil, the current or voltage varying according to a distance between the moving coil and the fixed coil; And
A camera module including a control unit for determining a position of the moving unit for focus based on the current or voltage generated according to the electromagnetic induction phenomenon. The camera module according to claim 1, wherein the fixed coil is disposed at a predetermined distance from one side of the moving part, and is located on a moving direction line of the moving part. The camera module of claim 1, wherein the number of turns of the fixed coil and the number of turns of the moving coil are different from each other. The camera module of claim 3, wherein the number of turns of the fixed coil is less than that of the moving coil. The method of claim 1,
The low frequency signal is for moving the moving part, and the high frequency signal is for determining the position of the moving part for the focus. The method of claim 1,
The camera module, further comprising a spring connected between the fixed part and the moving part to provide an elastic force according to the movement of the moving part. The camera module of claim 6, wherein a damper is disposed between the spring and the fixing part. The camera module according to claim 7, wherein the damper is disposed adjacent to a connection end of the spring and the fixing part. The method of claim 1,
The camera module further comprising a detection unit for detecting a displacement value of the current or voltage generated in the fixed coil according to the electromagnetic induction phenomenon. The method of claim 9, wherein the detection unit,
A half-wave rectifying unit rectifying a frequency signal for a current or voltage received from the fixed coil into a half-wave signal;
A conversion unit converting a half wave signal received from the half wave rectifier into a current or voltage;
An amplification unit amplifying a frequency signal for the current or voltage converted from the conversion unit; And,
And a peak detection unit detecting a peak of the frequency signal amplified by the amplifying unit. The method of claim 1,
An image sensor for sensing an image incident through the lens of the moving part; And
Further comprising; an image signal processing unit for processing the image signal sensed from the image sensor,
The control unit,
A focus position value is calculated based on the image signal processed by the image signal processing unit and the displacement value of the current or voltage,
The camera module, characterized in that the movement of the moving part is controlled by the calculated optimal focus position value. delete delete delete

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