KR102405978B1 - Voice coil motor - Google Patents

Abstract

The voice coil motor includes a stator including a first driving unit; a mover disposed inside the stator and including a second driving unit reacting with the first driving unit and having a lens mounted therein; a base for fixing the stator; and an elastic member coupled to the mover to space the mover apart from the base when a driving signal is not applied to the first or second driving unit, wherein the mover moves toward the base in a first direction or the It is moved in a second direction away from the base, and a movement section of the mover is longer than an effective focus section of the lens.

Description

Voice coil motor {VOICE COIL MOTOR}

The present invention relates to a voice coil motor.

Recently, a mobile phone having a built-in micro digital camera has been developed.

In the case of a miniature digital camera applied to a conventional mobile phone, etc., it was not possible to adjust the distance between the image sensor and the lens for changing external light into a digital image or digital image, but recently, a voice coil motor for adjusting the distance between the image sensor and the lens and With the development of the same lens drive device, an improved digital image or digital image can be obtained from a miniature digital camera.

In general, the voice coil motor has a lens mounted therein, and a bobbin disposed on the base moves upward from the base to adjust the distance between the lens and the image sensor disposed on the rear side of the base.

In addition, a leaf spring is coupled to the bobbin of the voice coil motor, and when the voice coil motor is not in operation, the bobbin is always in contact with the upper surface of the base by the elastic force of the leaf spring. That is, the bobbin of the conventional voice coil motor is driven only in one direction with respect to the base.

Since the conventional voice coil motor is driven in only one direction, a driving force greater than the weight of the bobbin and the elastic force of the leaf spring is required to drive the voice coil motor, and thus power consumption of the voice coil motor is greatly increased.

In addition, since a driving force greater than the bobbin's own weight and the elastic force of the leaf spring is required to drive the voice coil motor, the size of the coil wound on the magnet or bobbin increases, thereby increasing the overall size of the voice coil motor.

(Patent Document 1) JP2008-281863 A

The present invention floats the mover from the base so that the mover can be driven in both directions with a smaller current, and focusing is implemented using the stabilized section in which the mover is stable without using the unstable section in which the mover tilts or shakes during operation. A voice coil motor with improved image quality is provided.

The technical problems to be achieved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by those of ordinary skill in the art to which the present invention belongs from the description below. will be.

In one embodiment, the voice coil motor includes a stator including a first driving unit; a mover disposed inside the stator and including a second driving unit reacting with the first driving unit and having a lens mounted therein; a base for fixing the stator; and an elastic member coupled to the mover to space the mover apart from the base when a driving signal is not applied to the first or second driving unit, wherein the mover moves toward the base in a first direction or the It is moved in a second direction away from the base, and a movement section of the mover is formed to be longer than an effective focus section of the lens.

In one embodiment, the voice coil motor includes a stator including a first driving unit; a mover disposed inside the stator and including a second driving unit reacting with the first driving unit and having a lens mounted therein; a base for fixing the stator; and an elastic member coupled to the mover to space the mover apart from the base when a driving signal is not applied to the first or second driving unit, wherein the mover moves toward the base in a first direction or the A tilt amount of the effective focus section of the lens that is moved in a second direction away from the base and included in the moving section of the mover according to a change in the amount of current supplied to either the first driving unit or the second driving unit is the effective focus interval It is smaller than the tilt amount of the ineffective focus section formed outside of .

According to the voice coil motor according to the present invention, in an unstable section in which shaking or tilting of the mover occurs due to a mixture of electromagnetic and elastic forces around the mover, infinity focus or close-up focus is not formed, and shaking or tilt of the mover does not occur. Infinity focus or close-up focus is formed in the stable section so that high-quality images or moving pictures can be generated from the image sensor.

1 is an exploded perspective view of a voice coil motor according to an embodiment of the present invention.
FIG. 2 is an assembly cross-sectional view of FIG. 1 .
3 is a cross-sectional view conceptually illustrating a voice coil motor according to an embodiment of the present invention.
4 is a graph showing the current-distance characteristic and the current-tilt amount characteristic of the mover of FIG. 3 together.

Hereinafter, an embodiment according to the present invention will be described in detail with reference to the accompanying drawings. In this process, the size or shape of the components shown in the drawings may be exaggerated for clarity and convenience of explanation. In addition, terms specifically defined in consideration of the configuration and operation of the present invention may vary depending on the intention or custom of the user or operator. Definitions of these terms should be interpreted as meanings and concepts consistent with the technical idea of the present invention based on the contents throughout this specification.

1 is an exploded perspective view of a voice coil motor according to an embodiment of the present invention. FIG. 2 is an assembled cross-sectional view of FIG. 1 .

1 and 2 , the voice coil motor 600 includes a stator 100 , a mover 200 , a base 300 , and an elastic member 400 . In addition, the voice coil motor 600 may include a cover 500 .

The stator 100 includes a coil block 120 and a housing 150 . The stator 100 generates a magnetic field for driving a mover 200 to be described later. Alternatively, the stator 100 may include a magnet generating a magnetic field and the housing 150 .

The coil block 120 is formed, for example, by winding a long wire insulated by an insulating resin into a tubular shape. When a voltage having a voltage difference is applied to the coil block 120 formed by winding a long wire insulated by an insulating resin, a magnetic field is generated from the coil block 120, and the direction of the magnetic field flows through the coil block 120. It changes according to the direction of the current.

The housing 150 fixes the coil block 120 . The housing 150 includes, for example, a housing body 152 and posts 154 .

The housing body 152 is formed in, for example, a rectangular plate shape, and an opening 153 exposing a lens mounted on a bobbin to be described later is formed in the central portion of the housing body 152 .

A plurality of coupling bosses 156 for fixing an upper elastic member to be described later are formed on the upper surface of the housing body 152 . The housing 150 may include a groove 155 that overlaps the connection elastic part 453 of the upper elastic member 450 in the optical axis direction and is recessed from the upper surface of the housing 150 .

The pillars 154 protrude from the four corners of the lower surface of the housing body 152 facing the base 300 , respectively. The inner surface of the coil block 120 is fixed to the outer peripheral surface of the pillars (154). The pillars 154 may be coupled to the upper surface of the base 300 to be described later.

In one embodiment of the present invention, the coil block 120 is attached to the pillars 154 of the housing 150 by an adhesive or the like in a state in which the coil block 120 is wound in a cylindrical shape or directly wound on the pillars 154 of the housing 150 . can be

The mover 200 includes a bobbin 210 and a magnet 250 . In an embodiment of the present invention, when the stator 100 includes the coil block 120 , the mover 200 includes a magnet 250 , and when the stator 100 includes a magnet, the mover 200 includes a coil block.

In an embodiment of the present invention, the mover 200 is driven in a first direction toward the base 300 or in a second direction away from the base 300 .

A cylindrical lens 205 is fixed inside the bobbin 210 . The mover 200 moves with respect to the stator 100 to adjust the distance between the image sensor and the lens 205 disposed on the lower surface of the base 300 to be described later.

The bobbin 210 is, for example, formed in a hollow cylindrical shape, and a screw thread for fixing the lens 205 is formed on the inner circumferential surface of the bobbin 210 .

Flat magnet fixing parts 215 for fixing the plurality of magnets 250 are formed on the outer peripheral surface of the bobbin 210 . For example, four magnet fixing parts 215 are formed at equal intervals on the outer peripheral surface of the bobbin 210 , for example.

The magnets 250 are, for example, formed in a plate shape, and the magnets 250 are fixed to each of the magnet fixing parts 215 formed on the outer peripheral surface of the bobbin 210 . Each of the magnets 250 may be attached to the magnet fixing part 215 by an adhesive or the like.

Each magnet 250 is disposed to face the coil block 120 of the stator 100 .

The base 300 is, for example, formed in the shape of a rectangular parallelepiped plate, and serves to fix the stator 100 .

The base 300 is, for example, formed in the shape of a rectangular parallelepiped plate, and serves to fix the stator 100 .

An opening 310 through which the light passing through the lens 205 built in the bobbin 210 of the mover 200 passes is formed in the central portion of the base 300 .

The four corners of the upper surface 320 of the base 300 formed in the shape of a plate are each formed with coupling pillars 325, and the coupling pillars 325 are for mutually coupling the cover 500 and the base 300 to be described later. plays a role

An IR filter 301 and an image sensor (not shown) that generate an image corresponding to the light passing through the lens 205 of the bobbin 210 are fixed to the rear surface of the base 300 .

Meanwhile, a bobbin receiving groove 330 concavely formed from the upper surface 320 is formed on the upper surface 320 of the base 300 . The bobbin receiving groove 330 serves to receive the lower end of the bobbin 210 .

The bobbin receiving groove 330 is formed to be larger than the planar area of the bobbin 210 , and the bobbin 210 and the base 300 may partially overlap each other by the bobbin receiving groove 330 .

In one embodiment of the present invention, the depth of the bobbin receiving groove 330 is formed in consideration of the stroke length of the mover 200 .

Meanwhile, the shock absorbing member 350 formed along the opening 310 of the base 300 is disposed on the bottom surface 335 of the base 300 formed by the bobbin receiving groove 330 . The shock absorbing member 350 absorbs, for example, a shock caused by a collision between the bobbin 210 and the bottom surface 335 of the base 300 .

In an embodiment of the present invention, the shock absorbing member 350 may include any one of a sponge, a synthetic resin having elasticity, and rubber, and the shock absorbing member 350 may be formed in an annular plate shape having a thin thickness. can

The lower elastic member 415 of the elastic member 400 elastically supports the bobbin 210 of the movable member 200 , and the lower elastic member 415 of the movable member 200 has a lower surface of the bobbin 210 of the base. (300) to float on the upper portion of the bobbin receiving groove (330).

That is, the lower elastic member 415 is formed on the lower surface of the bobbin 210 and the upper surface 320 of the base 300 regardless of the posture of the bobbin 210 when no current is applied to the coil block 120 . A gap is formed between the bottom surfaces 335 formed by the receiving grooves 330 .

Here, the posture of the bobbin 210 means that the lens of the bobbin 210 faces downward, the lens of the bobbin 210 faces upward, or the lens of the bobbin 210 is disposed parallel to the ground.

The lower elastic member 415 includes an inner lower elastic part 410 , an outer lower elastic part 420 , and a connection lower elastic part 430 .

The inner lower elastic part 410 is formed in, for example, an annular ring shape, and the inner lower elastic part 410 is coupled to the lower surface of the bobbin 210 . The inner lower elastic part 410 is coupled to the lower surface of the bobbin 210 by, for example, an adhesive or thermal fusion.

Since the inner lower elastic part 410 is coupled to the lower surface of the bobbin 210 , the inner lower elastic part 410 is also formed in a size to be inserted into the bobbin receiving groove 330 of the base 300 .

The outer lower elastic part 420 is disposed outside the inner lower elastic part 410 , and the outer lower elastic part 420 is formed in a rectangular frame shape.

The outer lower elastic part 420 is formed in a size larger than the bobbin receiving groove 330 of the base 300 , and thus the outer lower elastic part 420 is disposed on the upper surface 320 of the base 300 . The outer lower elastic part 420 may be fixed on the upper surface 320 of the base 300 by, for example, pillars 154 of the housing 150 of the stator 100 .

The connection lower elastic part 430 elastically connects the inner lower elastic part 410 and the outer lower elastic part 420 to each other, and the inner lower elastic part 410 has elasticity by the connection lower elastic part 430 . do.

In one embodiment of the present invention, the bobbin 210 is floated on the upper portion of the bobbin receiving groove 330 of the base 300 by the lower elastic member 415 .

The inner lower elastic part 410 is spaced apart from the bottom surface 335 formed by the bobbin receiving groove 330, and when a driving signal is not applied to the coil block 120, the inner lower elastic part 410, the outer The lower elastic part 420 and the connecting lower elastic part 430 may be disposed on the same plane. Alternatively, when a driving signal is not applied to the coil block 120 , the inner lower elastic part 410 may be disposed at a slightly lower position than the outer lower elastic part 420 .

In one embodiment of the present invention, when the concave bobbin receiving groove 330 is formed in the upper surface 320 of the base 300, the bobbin receiving groove 330 is used while reducing the overall volume of the voice coil motor 600 Thus, the mover 200 may be driven in a first direction toward the base 300 or in a second direction in which the mover 200 moves away from the base 300 , respectively.

That is, when the mover 200 is spaced apart from the upper surface 320 of the lower base 300 , the mover 200 faces the base 300 by changing the direction of the current applied to the coil block 120 . Each may be driven in a first direction or a second direction away from the base 300 .

Meanwhile, the upper elastic member 450 is coupled to the coupling boss 156 formed on the upper surface of the housing body 152 of the housing 150 of the stator 100 .

The upper elastic member 450 includes an inner upper elastic part 451 , an outer upper elastic part 452 , and a connection upper elastic part 453 .

The inner upper elastic part 451 is coupled to the upper surface of the bobbin 210 , and the outer upper elastic part 452 is disposed on the upper surface of the housing body 152 . The connection upper elastic part 453 connects the outer and inner upper elastic parts 451 and 452.

A coupling hole 455 coupled to the coupling boss 156 formed on the top surface of the housing body 152 is formed in the outer upper elastic part 452 disposed on the upper surface of the housing body 152 .

Referring back to FIG. 1 , the voice coil motor 600 may further include a cover 500 .

The cover 500 includes an upper plate 510 having an opening exposing the lens 205 of the mover 200 and a side plate 520 extending from the edge of the upper plate 510 toward the base 300 . and the side plate 520 is coupled to the side surface of the base 300 .

Referring to FIG. 2 , the bobbin 210 of the mover 200 according to an embodiment of the present invention has an upper surface 320 of the base 300 by the force generated from the coil block 120 and the magnet 250 . ) may be driven in a first direction and a second direction away from the base 300 in a direction opposite to the first direction, respectively.

The forward current or reverse current applied to the coil block 120 may be implemented by adjusting the voltage difference applied to both ends of the coil block 120 , and the voltage difference may be implemented by, for example, a PWM circuit.

3 is a cross-sectional view conceptually illustrating a voice coil motor according to an embodiment of the present invention. 4 is a graph showing the current-distance characteristic and the current-tilt amount characteristic of the mover of FIG. 3 together.

3 and 4 , the voice coil motor 600 includes a base 300 , a stator 100 , a mover 200 , an elastic member 400 , and a cover 500 .

The base 300 is formed in a plate shape in which an opening through which light passes is formed in the center, and the base 300 serves as a lower stopper of the mover 200 .

A receiving groove for accommodating the lower surface of the mover 200 may be formed in the upper surface of the base 300 to space the lower surface of the mover 200 and the upper surface of the base 300 apart.

A shock absorbing member 350 is disposed on the upper surface of the base 300 to prevent the mover 200 and the base 300 from colliding and generating noise.

The shock absorbing member 350 may include, for example, any one of a sponge, a synthetic resin having elasticity, and rubber.

The image sensor 1 may be disposed on the rear side of the base 300 or on the rear side of the base 300 . The image sensor 1 changes the light incident through the mover 200 into a digital image or a moving picture.

The stator 100 is fixed on the base 300 , and the stator 100 includes a coil block 120 that is a first driving unit for generating a magnetic field, and an accommodation space is formed inside the stator 100 .

In one embodiment of the present invention, the coil block 120 as the first driving unit may include, for example, a coil wound with a long wire insulated by an insulating resin to generate a magnetic field by an electric current.

The mover 200 is disposed inside the stator 100 , and the mover 200 includes a lens 205 . A magnet including a second driving unit generating a magnetic field is mounted on the outer surface of the mover 200 .

In an exemplary embodiment of the present invention, when the first driving unit of the stator 100 includes the coil block 120 , the second driving unit of the mover 200 may include the magnet 250 . Alternatively, the first driving unit of the stator 100 may include a magnet, and when the first driving unit of the stator 100 includes a magnet, the second driving unit includes a coil block.

One side of the elastic member 400 is fixed to the mover 200 , and the other side opposite to the one side is fixed to the stator 100 , and the elastic member 400 elastically supports the mover 200 .

In one embodiment of the present invention, the elastic member 400 includes a first elastic member 415 formed at the lower end of the outer circumferential surface of the mover 200 and a second elastic member 450 formed at the upper end of the outer circumferential surface of the mover 200 . may include

The first elastic member 415 and the second elastic member 450 constituting the elastic member 400 are spaced apart from the upper surface of the base 300 when power is not applied to the coil block 120 of the stator 100, In this case, an offset (step difference) is not formed on the first and second elastic members 415 and 450 .

The elastic member 400 separates the mover 200 from the upper surface of the base 300 when a driving signal is not applied to the coil block 120 for generating a magnetic field.

The cover 500 is fixed to the base 300 , and the cover 500 surrounds the stator 100 and the mover 200 . Also, the cover 500 serves as an upper stopper that stops the mover 200 .

A shock absorbing member 355 is disposed on the cover 500 to prevent the mover 200 and the cover 500 from colliding and generating noise. The shock absorbing member 355 may include, for example, any one of a sponge, a synthetic resin having elasticity, and rubber.

3 and 4, in one embodiment of the present invention, the mover 200 of the voice coil motor 600 is the upper surface of the base 300 and the cover ( 500) is moved between the inner surfaces.

Hereinafter, in an embodiment of the present invention, the upper surface of the base 300 serving as a lower stopper of the mover 200 of the voice coil motor 600 and the cover 500 serving as an upper stopper of the mover 200 are provided. The interval between the inner surfaces is defined as a “moving section”.

That is, the movement section may be defined as a section between the contact surfaces of the mover 200 and the base 300 and the contact surfaces of the mover 200 and the cover 500 .

In order to realize a specific focus on the image sensor 1 by driving the mover 200 of the voice coil motor 600 shown in FIG. 3 , first, an initial value of 0 [mA] is applied to the coil block 120 of the stator 100 . A driving signal of A [mA] is applied from the driving signal S, whereby the mover 200 moves in a first direction toward the upper surface of the base 300 and comes into contact with the upper surface of the base 300 .

After the mover 200 is in contact with the upper surface of the base 300, the coil block 120, which is the first driving unit of the stator 100, has a current continuously increasing from A [mA] to less than B [mA] again. provided

However, even if a continuously increasing current of less than A [mA] to B [mA] is provided to the coil block 120 , which is the first driving unit of the stator 100 , the mover 200 is spaced apart from the upper surface of the base 300 . doesn't happen

This is when a current of less than B [mA] is applied to the coil block 120, which is the first driving unit of the stator 100, acting between the coil block 120 as the first driving unit and the magnet 250 as the second driving unit. This is because the electromagnetic force is smaller than the elastic force of the elastic member 400 and/or the self-weight of the movable element 200 .

Meanwhile, referring to the tilt graph of the mover 200 indicated by the solid line in FIG. 4 , the current continuously increasing from A [mA] to less than B [mA] is applied to the coil block 120 of the stator 100. At this time, severe shaking or tilt is generated in the mover 200 .

The shake or tilt of the mover 200 is greatest at a current greater than B[mA] and smaller than C[mA].

However, when a current of C [mA] or more is applied to the coil block 120, which is the first driving unit of the stator 100, shaking or tilting of the mover 200 does not occur.

Therefore, in one embodiment of the present invention, when forming the infinity focus, the current applied to the coil block 120 corresponding to the section generating the unstable tilt of the mover 200 is between A [mA] to C [mA] is the current

When a current less than A [mA] to B [mA] is applied to the coil block 120 of the stator 100 , the mover 200 is in contact (D) with the upper surface of the base 300 .

When a current less than C [mA] is applied to the coil block 120, which is the first driving unit of the stator 100, the mover 200 is spaced apart from the upper surface of the base 300 at the position E of the distance axis of the graph. are placed

Hereinafter, in an embodiment of the present invention, a section D-E, which is a section in which shaking or tilt of the mover 200 occurs, is defined as an “ineffective focus section”, and E in which shaking or tilt of the mover 200 does not occur The above section is defined as an "effective focus section".

The effective focus section is formed between the moving sections of the mover 200 , and the ineffective focus section is present on both sides of the effective focus section, respectively.

If a specific focus, for example, infinity focus, is formed within the ineffective focus section, severe shaking or tilting may occur in the mover 200 when photographing a subject with infinity focus. The focusing operation is not performed in the effective focus period, but the focusing operation is performed in the effective focus period E or higher of the graph of FIG. 4 .

In one embodiment of the present invention, infinity focus is not formed in the ineffective focus section, but infinity focus is formed in the effective focus section.

In one embodiment of the present invention, the ineffective focus section in which shaking and tilt of the mover 200 occurs may start from, for example, a position spaced apart from the upper surface of the base 300 by about 5 μm to about 20 μm. have.

In addition, in one embodiment of the present invention, the infinity focus is preferably formed at a position spaced apart from the upper surface of the base 300 by about 10 μm, thereby forming the infinity focus without shaking or tilting the mover 200 . .

On the other hand, when forming the macro focus, the distance from the inner surface of the cover 500 to a location spaced apart by a predetermined distance is an ineffective focus section where shaking and tilting of the mover 200 occurs like infinity focus, so the macro focus is the lens 205 ) and is formed in an effective focus section spaced apart from the inner surface of the cover 500 by about 5 μm to about 20 μm.

In an embodiment of the present invention, the current F [mA] applied to the coil block 120 when the mover 200 reaches a position forming the macro focus may be, for example, about 20 [mA]. have.

In conclusion, in an embodiment of the present invention, the effective focus section exists within the movement section of the mover 200 , and the effective focus section is located 5 μm to 20 μm apart from the upper surface of the base 300 and the base 300 . It is coupled to the stator 100 and the mover 200 is formed between the position spaced apart from the inner surface of the cover 500, 5㎛ to 20㎛.

In addition, infinity focus is formed at the end of the effective focus section adjacent to the base 300 , and close-up focus is formed at the end of the effective focus section adjacent to the cover 500 .

Although it is shown and described that the first driving unit of the stator 100 includes the coil block 120 and the second driving unit of the mover 200 is the magnet 250 in an embodiment of the present invention, on the contrary The first driving unit of the stator 100 may include a magnet and the second driving unit may include a coil block.

On the other hand, the tilt amount of the mover 200 in the effective focus section and the ineffective focus section is changed according to the amount of current applied to the coil block 120, and in an embodiment of the present invention, the movement of the mover 200 The amount of shaking and/or tilt of the mover 200 in the effective focus section included in the moving section is included in the movement section and shaking and/or tilting of the mover 200 in the ineffective focus section formed on both sides of the effective focus section. smaller than the tilt amount.

In one embodiment of the present invention, although the mover 200 has a minute shake or a minute tilt amount in the effective focus section, the shake or tilt amount of the mover 200 in the effective focus section is negligible compared to the ineffective focus section. Since it is small enough, it can be defined as substantially no tilt amount in the effective focus section.

As described in detail above, in the unstable section in which shaking or tilting of the mover occurs due to a mixture of electromagnetic force and elastic force around the mover, infinity focus or macro focus is not formed and stable section in which shaking or tilting of the mover does not occur. Infinity focus or close-up focus is formed in the image sensor to generate high-quality images or moving pictures.

Although the embodiments according to the present invention have been described above, these are merely exemplary, and those of ordinary skill in the art will understand that various modifications and equivalent ranges of embodiments are possible therefrom. Accordingly, the true technical protection scope of the present invention should be defined by the following claims.

100..Voice Coil Motor 110...Bass
120...stator 130...mover
140...Elastic member 150...Cover

Claims (22)

a cover including an upper plate and a side plate extending from the upper plate;
a base coupled to the side plate of the cover;
a bobbin disposed between the upper plate of the cover and the base;
a housing disposed between the bobbin and the cover;
a coil disposed on the bobbin;
a magnet facing the coil; and
An upper elastic member connecting the bobbin and the housing,
The upper elastic member includes an inner elastic part coupled to the bobbin, an outer elastic part disposed on the upper surface of the housing, and a connecting elastic part connecting the inner elastic part and the outer elastic part,
The housing includes a groove that overlaps the connection elastic part of the upper elastic member in an optical axis direction and is recessed from the upper surface of the housing,
When a reverse driving current is supplied to the coil from an initial position, the bobbin moves in a first direction approaching the base in an optical axis direction, and when a forward driving current is supplied, a second direction approaches the upper plate of the cover in the optical axis direction go to,
The moving section of the bobbin includes a first section in which the bobbin moves in a first direction from the initial position to the base and a second direction in which the bobbin moves closer to the upper plate of the cover from the initial position. Includes 2 sections,
The distance of the first section is smaller than the distance of the second section. According to claim 1,
The first section is a section from the initial position of the bobbin to a first position that is an infinity focus position, and the second section is a section from the initial position of the bobbin to a second position that is a macro focus position. . 3. The method of claim 2,
The movement section of the bobbin includes a first distance that is a distance from the first position to a contact surface of the bobbin and the base based on the optical axis direction, and a first distance between the bobbin and the cover at the second position based on the optical axis direction. Including a second distance, which is a distance to the contact surface of the inner surface of the upper plate,
The first distance in the movement section of the bobbin is different from the second distance. 3. The method of claim 2,
The movement section of the bobbin includes a first distance that is a distance from the first position to a contact surface of the bobbin and the base based on the optical axis direction, and a first distance between the bobbin and the cover at the second position based on the optical axis direction. Including a second distance, which is a distance to the contact surface of the inner surface of the upper plate,
The first distance in the movement section of the bobbin is greater than the second distance. 3. The method of claim 2,
The movement section of the bobbin includes a first distance that is a distance from the first position to a contact surface of the bobbin and the base based on the optical axis direction, and a first distance between the bobbin and the cover at the second position based on the optical axis direction. Including a second distance, which is a distance to the contact surface of the inner surface of the upper plate,
In the initial position where no current is applied to the coil, the bobbin is spaced apart from the base by the first distance or more, and the cover is spaced apart from the lens by the second distance or more. According to claim 1,
The bobbin is spaced apart from the top plate of the base and the cover in the initial position where no current is applied to the coil,
The bobbin is spaced apart from the top plate of the base and the cover in all positions of the first section and the second section. According to claim 1,
The housing includes an upper surface on which the upper elastic member is disposed, and a boss protruding from the upper surface of the housing. 8. The method of claim 7,
The outer elastic part of the upper elastic member includes a hole through which the boss of the housing passes. According to claim 1,
The magnitude of the absolute value of the current applied to the coil to move the bobbin to the infinity focus position is smaller than the magnitude of the absolute value of the current applied to the coil to move the bobbin to the macro focus position. According to claim 1,
The bobbin moves within the first section and the second section when a driving current is applied to the coil, and moves beyond the first section and the second section when a current greater than the driving current is applied to the coil lens drive device. 3. The method of claim 2,
The movement section of the bobbin includes a first distance that is a distance from the first position to a contact surface of the bobbin and the base based on the optical axis direction, and a first distance between the bobbin and the cover at the second position based on the optical axis direction. Including a second distance, which is a distance to the contact surface of the inner surface of the upper plate,
The bobbin moves within the first distance and the second distance when a current greater than the driving current is applied to the coil. 3. The method of claim 2,
The movable distance of the bobbin is a distance between a position where the bobbin contacts the base and a position where the bobbin contacts the upper plate of the cover,
The movable distance of the bobbin is greater than the sum of the lengths of the first section and the second section of the bobbin. 10. The method of claim 9,
The infinity focus position is a position in which the bobbin is spaced apart from the upper surface of the base by 5 μm to 20 μm in the optical axis direction. According to claim 1,
a distance between the initial position of the bobbin and an infinity focus position is smaller than a distance between the initial position of the bobbin and a macro-focus position. 10. The method of claim 9,
The macro focus position is a position in which the bobbin is spaced apart from the inner surface of the upper plate of the cover by 5 μm to 20 μm in an optical axis direction. According to claim 1,
and a lower elastic member coupled to a lower portion of the bobbin. 11. The method of claim 10,
When the driving current is applied to the coil, the bobbin does not come into contact with the upper plate of the cover. 11. The method of claim 10,
A lens driving device configured to prevent the bobbin from contacting the base when the driving current is applied to the coil. image sensor;
The lens driving device of claim 1; and
and a lens coupled to the bobbin of the lens driving device. A mobile phone comprising the camera of claim 19 . 3. The method of claim 2,
The movement section of the bobbin includes a first distance that is a distance from the first position to a contact surface of the bobbin and the base with respect to the optical axis direction. 3. The method of claim 2,
The movement section of the bobbin includes a second distance that is a distance from the second position to a contact surface of the inner surface of the upper plate of the cover and the bobbin from the second position with respect to the optical axis direction.

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