KR20220045517A - A lens moving unit, and camera module and optical instrument including the same - Google Patents

Abstract

One embodiment comprises: a housing; a bobbin disposed within the housing; an elastic member coupled to the bobbin and the housing; a shape memory alloy member coupled to the bobbin and the elastic member; and a sensing magnet and position sensor to detect bobbin movement in an optical axis direction. Through the elastic member, a position sensor supplies a driving signal to the shape memory alloy member. Accordingly, it is possible to improve the accuracy of temperature compensation according to a change of ambient temperature.

Description

A lens driving device, and a camera module and optical device including the same

The embodiment relates to a lens driving device, a camera module and an optical device including the same.

Since it is difficult to apply the technology of a voice coil motor (VCM) used in an existing general camera module to a camera module for ultra-small size and low power consumption, research related thereto has been actively conducted.

Demand and production of electronic products such as smartphones and camera-equipped cell phones are increasing. Cameras for mobile phones are on the trend of high resolution and miniaturization, and accordingly, actuators are becoming smaller, larger diameter, and multi-functional. In order to implement a high-resolution mobile phone camera, additional functions such as performance improvement of mobile phone camera, auto focusing, shutter shake improvement, and zoom function are required.

The embodiment provides a lens driving device capable of improving the accuracy of temperature compensation according to a change in ambient temperature and improving the reliability of an electrical connection between a shape memory alloy member and a circuit board, and a camera module and optical device including the same .

A lens driving device according to an embodiment includes a housing; a bobbin disposed within the housing; an elastic member coupled to the bobbin and the housing; a shape memory alloy member coupled to the bobbin and the elastic member; and a sensing magnet and a position sensor for sensing movement of the bobbin in an optical axis direction, wherein the position sensor supplies a driving signal to the shape memory alloy member through the elastic member.

The elastic member may electrically connect the position sensor and the shape memory alloy member.

The elastic member may be coupled to an upper portion of the bobbin and an upper portion of the housing.

The shape memory alloy member may include a first member, at least a portion of which supports the first portion of the bobbin, and a second member, at least a portion of which supports the second portion of the bobbin.

Each of the first part and the second part may be a protrusion protruding from an outer surface of the bobbin.

The elastic member may include a first elastic member connected to one end of the first member; a second elastic member connected to the other end of the first member and one end of the second member; and a third elastic member connected to the other end of the second member.

a circuit board including a first pad electrically connected to the first elastic member, a third pad electrically connected to the second elastic member, and a third pad electrically connected to the third elastic member can

The driving signal may be a PWM signal.

and a base disposed under the bobbin and the housing, wherein when a driving signal is not provided to the shape memory alloy member, the bobbin may contact the base.

and a circuit board on which the position sensor is disposed, and the elastic member may be electrically connected to the circuit board.

The sensing magnet may be disposed on the bobbin, and the position sensor may be disposed on the housing.

The position sensor may include a Hall sensor and a driver.

The position sensor may include a temperature sensing element for measuring an ambient temperature of the shape memory alloy member.

The position sensor may include a resistance measuring unit for measuring resistance of the shape memory alloy member.

Each of the first to third elastic members includes an outer frame coupled to an upper portion of the housing, and one end of the first member is coupled to the outer frame of the first elastic member, the other end of the first member and One end of the second member may be coupled to the outer frame of the second elastic member, and the other end of the second member may be coupled to the outer frame of the third elastic member.

A lens driving device according to another embodiment includes a housing; a bobbin disposed within the housing; a first elastic member coupled to an upper portion of the bobbin and an upper portion of the housing; a second elastic member coupled to a lower portion of the bobbin and a lower portion of the housing; a first shape memory alloy member coupled to the bobbin and the first elastic member; a second shape memory alloy member coupled to the bobbin and the second elastic member; and a sensing magnet and a position sensor for sensing movement of the bobbin in an optical axis direction, wherein the first elastic member electrically connects the position sensor and the first shape memory alloy member, and the second elastic member includes The position sensor and the second shape memory alloy member are electrically connected.

A first driving signal may be supplied to the first shape memory alloy member through the first elastic member.

A second driving signal may be supplied to the second shape memory alloy member through the second elastic member.

The first shape memory alloy member may include a first member at least partially supporting the first portion of the bobbin and a second member at least partially supporting the second portion of the bobbin.

The second shape memory alloy member may include a third member at least partially supporting the third portion of the bobbin and a fourth member at least partially supporting the fourth portion of the bobbin.

Each of the first to fourth portions may be a protrusion protruding from an outer surface of the bobbin.

and a base disposed under the bobbin and the housing, and in an initial position, the bobbin may be positioned to be spaced apart from the base in an optical axis direction.

The first elastic member may include a first upper elastic member connected to one end of the first member; a second upper elastic member connected to the other end of the first member and one end of the second member; and a third upper elastic member connected to the other end of the second member.

The second elastic member may include a first lower elastic member connected to one end of the third member; a second lower elastic member connected to the other end of the third member and one end of the fourth member; and a third lower elastic member connected to the other end of the fourth member.

and a circuit board including a plurality of pads electrically connected to the first to third upper elastic members and the first to third lower elastic members.

A first section in which the bobbin moves in an upward direction based on the initial position may be larger than a second section in which the bobbin moves in a downward direction based on the initial position.

The bobbin is moved in the optical axis direction by the first shape memory alloy and the second shape memory alloy, and in the movement section of the bobbin in the optical axis direction, the length of each of the first and second shape memory alloys is It may be converted within 2% of the total length of the shape memory alloy member.

A lens driving device according to another embodiment includes a housing; a bobbin disposed within the housing; an elastic member coupled to the bobbin and the housing; and a shape memory alloy member coupled to the bobbin and the elastic member, wherein the elastic member includes a first elastic member, a second elastic member, and a third elastic member, wherein the shape memory alloy member has one end a first member coupled to the first elastic member, the other end coupled to the second elastic member, and a middle portion supporting the first portion of the bobbin; and a second member having one end coupled to the third elastic member, the other end coupled to the second elastic member, and a middle portion supporting the second portion of the bobbin.

A lens driving device according to another embodiment includes a housing; a bobbin disposed within the housing; an elastic member coupled to the bobbin and the housing; a shape memory alloy member coupled to the bobbin and the elastic member; a sensing magnet and a position sensor for detecting movement of the bobbin in an optical axis direction; and a circuit board electrically connected to the position sensor, wherein the shape memory alloy member is electrically connected to the circuit board through the elastic member.

The embodiment may improve accuracy of temperature compensation according to changes in ambient temperature, and may improve reliability of an electrical connection between the shape memory alloy member and the circuit board.

1 is an exploded view of a lens driving device according to an embodiment.
FIG. 2 shows the lens driving device excluding the cover member of FIG. 1 .
3A is an exploded perspective view of the bobbin, the sensing magnet, and the balancing magnet shown in FIG. 1 .
FIG. 3B is a combined perspective view of the bobbin shown in FIG. 3A, the sensing magnet, and the balancing magnet.
4A is a perspective view of the housing, the position sensor, and the capacitor shown in FIG. 1 ;
4B is a perspective view of the housing 140 to which the circuit board and the position sensor are coupled.
5 is a perspective view of an upper elastic member;
6 is a perspective view of the base;
7 is a perspective view of a base, a lower elastic member, and a circuit board;
Fig. 8A is a cross-sectional view of the lens driving device in the direction AB of Fig. 2 .
Fig. 8B is a cross-sectional view of the lens driving device in the CD direction of Fig. 2;
9 shows an electrical connection relationship between an upper elastic member, a shape memory alloy member, and a circuit board.
10A is a perspective view of a partial configuration of a lens driving device according to another exemplary embodiment.
FIG. 10B illustrates electrical connection of the shape memory alloy member, the lower elastic member, and the circuit board of FIG. 10A .
11A is a diagram illustrating a configuration of a position sensor according to an embodiment.
11B is a block diagram of a position sensor according to another exemplary embodiment.
12 is a view for explaining the relationship between the temperature, resistance, and length of the shape memory alloy member.
13 illustrates an operation section of the first and second shape memory alloy members for bidirectional driving.
14 illustrates a temperature compensation method according to an embodiment.
15 illustrates a temperature compensation method according to another exemplary embodiment.
16 is an exploded perspective view of a camera module according to an embodiment.
17 is a perspective view of a portable terminal according to an embodiment.
18 is a block diagram of the portable terminal shown in FIG. 17 .

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

However, the technical spirit of the present invention is not limited to some embodiments described, but may be implemented in various different forms, and within the scope of the technical spirit of the present invention, one or more of the components may be selected between the embodiments. It can be used by combining or substituted with .

In addition, the terms (including technical and scientific terms) used in the embodiments of the present invention have meanings that can be generally understood by those of ordinary skill in the art to which the present invention belongs, unless specifically defined and described explicitly. may be interpreted, and the meanings of commonly used terms such as predefined terms may be interpreted in consideration of the contextual meaning of the related art.

In addition, the terms used in the embodiments of the present invention are for describing the embodiments and are not intended to limit the present invention. In this specification, the singular form may also include the plural form unless otherwise specified in the phrase, and when it is described as "at least one (or one or more) of A and (and) B, C", it can be combined with A, B, and C. It may include one or more of all possible combinations.

In addition, in describing the components of the embodiment of the present invention, terms such as first, second, A, B, (a), (b), etc. may be used. These terms are only for distinguishing the component from other components, and are not limited to the essence, order, or order of the component by the term.

And, when it is described that a component is 'connected', 'coupled' or 'connected' to another component, the component is not only directly connected, coupled or connected to the other component, but also with the component It may also include a case of 'connected', 'coupled' or 'connected' due to another element between the other elements. In addition, when it is described as being formed or disposed on "above (above) or under (below)" of each component, top (above) or under (below) is one as well as when two components are in direct contact with each other. Also includes a case in which another component as described above is formed or disposed between two components. In addition, when expressed as "upper (upper) or lower (lower)", a meaning of not only an upper direction but also a lower direction based on one component may be included.

'Auto-focusing' refers to automatically focusing the image of the subject on the image sensor surface. The lens driving apparatus according to the embodiment may perform an auto-focusing operation of moving an optical module including at least one lens in a first direction.

Hereinafter, the lens driving device may be referred to as a lens driving unit, an actuator, or a lens moving device, and the term "elastic member" may be expressed by replacing it with an elastic unit or a spring.

Also, in the following description, the term “terminal” may be replaced with a pad, an electrode, a conductive layer, or a bonding part.

For convenience of description, the camera module according to the embodiment is described using a Cartesian coordinate system (x, y, z), but may be described using other coordinate systems, and the embodiment is not limited thereto. In each figure, the x-axis and y-axis refer to directions perpendicular to the z-axis, which is the optical axis direction, the z-axis direction, which is the optical axis (OA) direction, is referred to as a 'first direction', and the x-axis direction is referred to as a 'second direction'. and the y-axis direction may be referred to as a 'third direction'.

1 is an exploded view of a lens driving device 100 according to an embodiment, and FIG. 2 shows the lens driving device 100 except for the cover member 300 of FIG. 1 .

1 and 2 , the lens driving device 100 may include a bobbin 110 , a housing 140 , an upper elastic member 150 , and a shape memory alloy member 310 .

Also, the lens driving device 100 may include a sensing magnet 180 and a position sensor 170 for AF feedback driving.

Also, the lens driving device 100 may include a balancing magnet 185 .

In addition, the lens driving apparatus 100 may further include a circuit board 190 electrically connected to the position sensor 170 . Also, the lens driving apparatus 100 may further include a capacitor 195 disposed on the circuit board 190 .

Also, the lens driving device 100 may further include at least one of the cover member 300 and the base 210 .

First, the bobbin 110 will be described.

The bobbin 110 is for mounting the lens module 400 , is disposed in the housing 140 , and moves in the optical axis OA direction or the first direction (eg, the Z axis direction) by the shape memory alloy member 310 . can be The bobbin 110 may be expressed by replacing it with a “lens holder” or a holder. The lens module 400 may include at least one of a lens and a lens barrel.

3A is an exploded perspective view of the bobbin 110, the sensing magnet 180, and the balancing magnet 185 shown in FIG. 1, and FIG. 3B is the bobbin 110, and the sensing magnet 180, shown in FIG. 3A. It is a combined perspective view of the balancing magnet 185 .

3A and 3B , the bobbin 110 is disposed in the housing 140 . The bobbin 110 may have an opening 101 for mounting the lens module 400 . For example, the opening 101 of the bobbin 110 may be a hole or a through-hole penetrating the bobbin 110 in the optical axis direction, and the shape may be a circle, an ellipse, or a polygon, but is not limited thereto.

The bobbin 110 is disposed on the upper part, the upper surface, or the upper part, and the first coupling part 113 for coupling and fixing to the first inner frame 151 of the upper elastic member 150, and the lower part, the lower surface, or the lower part It may include a second coupling portion 117 disposed and coupled to and fixed to the second inner frame 161 of the lower elastic member 160 .

In FIGS. 3A and 3B , the first and second coupling parts 113 and 117 have a protrusion shape, but are not limited thereto. In another embodiment, the first and second coupling parts 113 and 117 may have a groove or planar shape.

The bobbin 110 may include a first escape groove 112a provided in an area of the upper surface corresponding to or aligned with the first frame connection part 153 of the upper elastic member 150 in the optical axis direction, and the first escape The groove 112a may be recessed from the upper surface of the bobbin 110 .

In addition, the bobbin 110 may include a second escape groove 112b in an area of a lower surface corresponding to or aligned with the second frame connection part 163 of the lower elastic member 160 in the optical axis direction, and the second escape groove (112b) may be in a shape recessed from the lower surface of the bobbin (110).

When the bobbin 110 moves in the first direction by the first escape groove 112a and the second escape groove 112b of the bobbin 110, the first frame connection part 153 and the second frame connection part 163 and Spatial interference between the bobbins 110 can be eliminated, and thereby the frame connection parts 153 and 163 can be easily elastically deformed.

The bobbin 110 may include a plurality of sides, sides, or outer surfaces. For example, the bobbin 110 may include side portions and corner portions. For example, the first to fourth corner portions of the bobbin 110 may be respectively disposed between two adjacent side portions of the bobbin 110 .

In addition, for seating of the sensing magnet 180 , the bobbin 110 may include a first groove 180a formed on one side thereof. For example, the groove 180a may be formed in any one outer surface of the bobbin 110 .

For example, in order to facilitate the mounting of the sensing magnet 180 , the first groove 180a may include an opening opened to the lower surface of the bobbin 110 . In addition, for the seating of the balancing magnet 185 , the bobbin 110 may include a second groove formed in a side opposite to the side in which the first groove 180a is formed.

The bobbin 110 may include a groove 119 that corresponds to, faces, or overlaps the protrusion 304 of the cover member 300 and is recessed from the upper surface. The groove 119 may include a side surface and a bottom surface.

In addition, the cover member 300 may include at least one protrusion 304 extending from an area of the upper plate 301 adjacent to the opening 303 toward the upper surface of the bobbin 110 or the groove 119 . The at least one protrusion 304 may be disposed in the groove 119 of the bobbin 110 .

In addition, when the AF is driven, the protrusion 304 of the cover member 300 may come into contact with the bottom surface of the groove 119 of the bobbin 110, thereby preventing movement of the bobbin 110 in the optical axis direction (eg, upward direction). It may serve as a stopper limiting within a preset range.

In another embodiment, the bobbin 110 may include a first stopper (not shown) protruding upward from the upper surface, and a second stopper (not shown) protruding downward from the lower surface. At this time, when the bobbin 110 is moved in the first direction for auto-focusing, the first and second stoppers are the upper or lower surfaces of the bobbin 110 even if the bobbin 110 moves beyond a prescribed range due to an external impact or the like. It may serve to prevent direct collision with the inner wall of the cover member 300 or the upper surface of the base 210 .

The bobbin 110 may include at least one protrusion 15A, 15B, 16A, and 16B protruding from an outer surface to support at least a partial region of the shape memory alloy member 310 .

Referring to FIGS. 3A and 3B , for example, a first protrusion 15A protruding in a horizontal direction may be formed on a first outer surface of the bobbin 110 , and a second outer surface of the bobbin 110 in a horizontal direction. It may include a second protrusion (16A) that protrudes. For example, the first outer surface and the second outer surface of the bobbin 110 may face each other or may be located opposite to each other. The sensing magnet 180 may be disposed on the third outer surface of the bobbin 110 , and the balancing magnet 185 may be disposed on the fourth outer surface of the bobbin 110 .

Here, the horizontal direction may be a direction perpendicular to the optical axis OA or a direction perpendicular to the optical axis OA and parallel to a straight line passing through the optical axis OA.

For example, the first protrusion 15A and the second protrusion 16A may be disposed to be more adjacent to the lower surface of the bobbin 110 than the upper surface of the bobbin 110 . For example, the first protrusion 15A and the second protrusion 16A may correspond to, face each other, or overlap each other in the horizontal direction. This is to allow the shape memory alloy member 310 to support the bobbin 110 in a balanced way.

In addition, each of the first protrusion 15A and the second protrusion 16A may include a curved surface convex in a downward direction. For example, each of the first protrusion 15A and the second protrusion 16A may have a hemispherical, semi-elliptical, or dome shape convex from the upper surface to the lower surface of the bobbin 110 . This is by making the portion where at least a portion of the shape memory alloy member 310 (3A and 3B) contact the curved or convex surfaces of the first protrusion 15A and the second protrusion 16A, so that the protrusions 15A and 15B and Frictional force between the shape memory alloy members 310 ( 3A and 3B ) may be reduced, and thus, disconnection of the shape memory alloy members 310 : 3A and 3B may be prevented.

In addition, a groove 109 in which at least a portion (eg, an intermediate portion, an intermediate region) of the shape memory alloy member 310 ( 3A, 3B) is disposed on the convex curved surface of each of the first and second projections 15A and 16A is provided. can be formed. By forming the groove 109, it is possible to prevent the shape memory alloy members 310 (3A, 3B) from being separated from the protrusions 15A and 15B, and thereby the shape memory alloy members 310 (3A and 3B) and the bobbin. It is possible to improve the binding force of (110).

Alternatively, for example, an upper portion of each of the first protrusion 15A and the second protrusion 16A may be flat, but is not limited thereto.

Due to the expansion and contraction of the shape memory alloy member 310 , the AF moving unit (or the AF moving unit) may move in a first direction, for example, in an upward direction (+Z axis direction) or a downward direction (−Z axis direction).

Next, the housing 140 will be described.

The housing 140 accommodates the bobbin 110 on which the sensing magnet 180 is mounted or disposed. The housing 140 may be disposed on the base 210 , and may be disposed inside the cover member 300 .

4A is a perspective view of the housing 140, the position sensor 170, and the capacitor 195 shown in FIG. 1, and FIG. 4B is a housing 140 to which the circuit board 190 and the position sensor 170 are coupled. 5 is a perspective view of the upper elastic member 150 , FIG. 6 is a perspective view of the base 210 , and FIG. 7 is a perspective view of the base 210 , the lower elastic member 160 , and the circuit board 190 . , FIG. 8A is a cross-sectional view of the lens driving device 100 in the AB direction of FIG. 2 , FIG. 8B is a cross-sectional view of the lens driving device 100 in the CD direction of FIG. 2 , and FIG. 9 is the upper elastic member 150 ), the shape memory alloy member 310 , and the circuit board 190 are electrically connected.

4A and 4B , the housing 140 accommodates the bobbin 110 inside so that the AF moving part, for example, the bobbin 110 can move in the optical axis direction.

The housing 140 may include an opening 140A for receiving or placing the bobbin 110 . The opening 140A may be a hole or a through hole passing through the housing 140 in the optical axis direction. For example, the housing 140 may have a column shape having an opening 140A.

The housing 140 may include a side portion 141 and a corner portion 142 defining an opening 140A. In FIG. 4A , one side portion 141 and one corner portion 142 of the housing 140 are indicated by reference numerals. For example, the housing 140 may include a plurality of side portions and a plurality of corner portions. Here, the corner portions of the housing 140 may be expressed by replacing the “pillars” of the housing 140 .

For example, the housing 140 may include sides and corners defining a polygonal (eg, square, or octagonal) or circular (or elliptical) opening 140A. For example, each of the side portions of the housing 140 may be disposed parallel to a corresponding one of the side plates 320 of the cover member 300 .

Each of the side portions of the housing 140 may correspond to any one of the side portions of the bobbin 110 , and each of the corner portions of the housing 140 may correspond to any one of the corner portions of the bobbin 110 . An inner surface of each of the corner portions of the housing 140 may be flat, chamfered, or curved.

In order to prevent the upper surface of the housing 140 from directly colliding with the inner surface of the upper plate 310 of the cover member 300, a stopper 143 formed to protrude from the upper portion, upper surface or upper end of the housing 140 may be included. can Here, the stopper 143 may be expressed by replacing it with a "protrusion (boss)" or "protrusion".

For example, in the initial position of the AF moving unit, the stopper 143 of the housing 140 may contact the inner surface of the upper plate 301 of the cover member 300 , but is not limited thereto. In other embodiments, the two may not be in contact.

The housing 140 may include at least one first coupling part 144 provided on the upper part, the upper surface, or the upper part of the housing 140 for coupling with the first outer frame 152 of the upper elastic member 150 . there is. In FIG. 4A , the first coupling part 144 of the housing 140 has a protrusion shape, but is not limited thereto. In another embodiment, the first coupling part 144 may be a groove or a flat shape.

In addition, the housing 140 includes at least one second coupling part 147 provided at the lower part, the lower surface, or the lower end of the housing 140 for coupling with the second outer frame 162 of the lower elastic member 160 . can do. In FIG. 4B , the second coupling part 147 has a protrusion shape, but is not limited thereto, and may be a groove or a flat shape in another embodiment.

In FIGS. 4A and 4B , the first and second coupling portions 144 and 147 are disposed at at least one of the corner portions of the housing 140 , but the present invention is not limited thereto. and at least one of the corner portions.

In order to prevent the lower surface or the bottom of the housing 140 from colliding with the base 210 to be described later, the housing 140 may include at least one stopper (not shown) protruding from the lower part, the lower surface, or the lower part.

A guide groove 148 corresponding to the protrusion 216 of the base 210 may be provided on a lower portion, a lower surface, or a lower end of at least one of the corner portions of the housing 140 .

For example, the guide groove 148 of the housing 140 and the protrusion 216 of the base 210 may be coupled to each other by an adhesive member, and the housing 140 may be coupled to the base 210 .

The housing 140 includes at least one of the sides of the housing 140 in order to avoid spatial interference between the first frame connection portion 153 of the upper elastic member 150 and the portion where the first outer frame 151 is connected. It may be provided with at least one escape groove (5A) provided on the upper portion, upper surface, or the upper end of the.

In addition, the housing 140 has at least one of the corner portions of the housing 140 in order to avoid spatial interference between the second frame connection portion 163 of the lower elastic member 160 and the portion where the second outer frame 161 is connected. At least one escape groove (5B) provided in one lower portion, lower surface, or lower end may be provided.

In another embodiment, one or more escape grooves 5A and/or escape grooves 5B of the housing 140 may be disposed on at least one of side surfaces or corner portions of the housing 140 .

A structure (eg, a groove or a protrusion) for coupling with the circuit board 190 may be provided on the side of the housing 140 . For example, a groove 25a for arranging the circuit board 190 may be formed on the outer surface of one side of the housing 140 , and the groove 25a may have the same shape or the same shape as that of the circuit board 190 . can have

For example, the circuit board 190 may be attached to one side (eg, the groove 25a) of the housing 140 by an adhesive or the like.

In addition, in order to seat the position sensor 170 , a first seating part 17a may be formed on either side of the housing 140 . In addition, a second seating portion 17b may be formed in any one corner portion (or first pillar portion) of the housing 140 to seat the capacitor 195 .

For example, the first seating portion 17a and the second seating portion 17b of the housing 140 may be formed in the groove 25a of the housing 140 to be spaced apart from each other.

For example, the first seating portion 17a formed on one side of the housing 140 may be located between two corner portions of the housing 140 located on both sides of the one side of the housing 140 , , the second seating portion 17b may be formed in any one of the two corner portions of the housing 140 .

In FIG. 4A , the first seating part 17a may be in the form of an opening or a through-hole penetrating the side of the housing 140 , whereby the housing 140 is interposed between the sensing magnet 180 and the position sensor 170 . By not doing so, it is possible to increase the output of the position sensor 170 , thereby improving the sensitivity of the position sensor 170 . In another embodiment, the first seating part may have a groove shape.

In addition, the second seating portion 17b may be in the form of a groove recessed from the outer surface of the corner portion of the housing 140 , and may not be in the form of a through hole. In another embodiment, the second mounting portion 17b may be in the form of an opening or a through hole.

Next, the sensing magnet 180 and the balancing magnet 185 will be described.

The sensing magnet 180 may be disposed on a side or an outer surface of the bobbin 110 facing or opposite to the position sensor 170 , and the balancing magnet 185 may be disposed on the bobbin 110 on which the sensing magnet 180 is disposed. It may be disposed on the other outer surface of the bobbin 110 located opposite to the side or the outer surface.

For example, the sensing magnet 180 may have a shape of a polyhedron, for example, a hexahedron.

For example, the sensing magnet 180 has an upper surface, a lower surface, a first surface facing the bobbin 110, a second surface opposite to the first surface, a first side connecting the first surface and the second surface, and a second surface It may include a second side opposite to the first side.

A part of any one surface of the sensing magnet 180 mounted in the groove 180a of the bobbin 110 may be exposed to the outer surface of the bobbin 110, but is not limited thereto, and in another embodiment, the bobbin 110 ) may not be exposed to the outer surface of

For example, the sensing magnet 180 may be inserted into the groove 180a through the opening of the groove 180a opened to the lower surface of the bobbin 110 . Also, for example, the sensing magnet 180 may be fixed or attached to the groove 180a of the bobbin 110 by an adhesive such as epoxy. The description of the sensing magnet 180 may be applied or analogously applied to the mounting of the bobbin 110 to the balancing magnet 185 .

Each of the sensing magnet 180 and the balancing magnet 185 may be a unipolar magnetizer disposed such that an upper surface is an N pole and a lower surface is an S pole, but is not limited thereto, and the polarity may be reversed.

For example, each of the sensing magnet 180 and the balancing magnet 185 may be disposed such that an interface between the N pole and the S pole is parallel to a direction perpendicular to the optical axis, but is not limited thereto. For example, in another embodiment, the interface between the N pole and the S pole may be parallel to the optical axis.

Alternatively, in another embodiment, each of the sensing magnet 180 and the balancing magnet 185 may be a bipolar magnet. In this case, the positively polarized magnet includes a first magnet part including an N pole and an S pole, a second magnet part including the S pole and the N pole, and a non-magnetic barrier rib positioned between the first magnet part and the second magnet part. can do.

When the AF is driven, the sensing magnet 180 may be moved together with the bobbin 110 in the optical axis direction OA, and the position sensor 170 may detect the strength of the magnetic field of the sensing magnet 180 moving in the optical axis direction. and may output an output signal according to the sensed result.

For example, the controller 830 of the camera module 200 or the controller 780 of the terminal 200A detects the displacement of the bobbin 110 in the optical axis direction based on the output signal output by the position sensor 170 . can

The balancing magnet 185 may be disposed on the bobbin 110 to balance the weight of the AF moving unit.

At least a part of the position sensor 170 and the sensing magnet 180 may overlap in a direction parallel to a straight line perpendicular to the optical axis and passing through the optical axis at the initial position of the moving unit (eg, the bobbin 110 ). In another embodiment, the two may not overlap each other.

Next, the position sensor 170 , the circuit board 190 , and the capacitor 195 will be described.

7 and 8 , the circuit board 190 and the position sensor 170 are disposed or coupled to either side of the housing 140 . For example, the circuit board 190 may be disposed on the outer surface of the side of the housing 140 .

For example, the circuit board 190 may be disposed in the groove 25a of the housing 140 . At least a portion of the first surface 19a of the circuit board 190 may be in contact with the groove 25a of the housing 140 .

The circuit board 190 may include at least one terminal 95 for electrically connecting to the outside. For example, the circuit board 190 may include a plurality of terminals B1 to B6 . Although 6 terminals are exemplified in FIG. 7 , the present invention is not limited thereto, and the number of terminals may be two or more.

Also, the circuit board 190 may include pads 9A to 9C electrically connected to the shape memory alloy member 310 .

For example, the circuit board 190 may be a printed circuit board or an FPCB.

For example, the pads 9A to 9C may be formed on the upper surface of the circuit board 180 connecting the first surface 19a and the second surface 19b. In another embodiment, the first to third pads may be formed on the first surface 19a of the circuit board 190 .

In another embodiment, the first to third pads may be formed on the second surface 19b of the circuit board 190 . In this case, the first to third upper elastic members may pass through at least a portion of the circuit board to be connected to or coupled to the first to third pads, respectively.

For example, the circuit board 190 may include grooves on its upper surface corresponding to the first to third upper elastic members. Each of the first to third upper elastic members may include an extension that passes through a corresponding groove of the circuit board 190 and is coupled to a corresponding pad.

The plurality of terminals B1 to B6 may be formed on the second surface 19b of the circuit board 190 .

For example, the plurality of terminals B1 to B6 may be arranged in a line at the lower end of the second surface 19b of the circuit board 190 , but is not limited thereto. In this case, the second surface 19b of the circuit board 190 may be opposite to the first surface 19a of the circuit board 190 .

In the embodiment shown in FIG. 7 , the circuit board 190 includes six terminals B1 to B6 , but is not limited thereto, and in another embodiment, there may be two or more or four.

The circuit board 190 electrically connects the position sensor 190 and at least one of the terminals B1 to B6 or electrically connects the pads 9A to 9C and at least one of the terminals B1 to B6. It may include a circuit pattern or wirings for

For example, the position sensor 170 may be mounted or disposed on the first surface 19a of the circuit board 190 . The position sensor 170 may be disposed on the first seating portion 17a of the housing 140 .

The position sensor 170 may sense the strength of the magnetic field of the sensing magnet 180 mounted on the bobbin 110 according to the movement of the bobbin 110 , and output an output signal (eg, output voltage) according to the sensed result. can be printed out.

The position sensor 170 may be implemented as a Hall sensor alone or in the form of a driver IC including a Hall sensor.

11A shows a configuration diagram of a position sensor 170 according to an embodiment.

Referring to FIG. 11A , the position sensor 170 may include a Hall sensor 61 and a driver 62 .

The Hall sensor 61 may generate an output VH according to a result of sensing the strength of the magnetic field of the sensing magnet 180 .

For example, the Hall sensor 61 may be made of silicon, and as the ambient temperature increases, the output VH of the Hall sensor 61 may increase. For example, the ambient temperature may include a temperature of the lens driving device 100 or the camera module 200 , for example, a temperature of the circuit board 190 or 800 , or a temperature of the image sensor 810 , a temperature of the Hall sensor 61 , Alternatively, it may be the temperature of the driver 62 .

Also, in another embodiment, the Hall sensor 61 may be made of GaAs, and the output VH of the Hall sensor 61 may have a slope of about -0.06%/°C with respect to the ambient temperature.

The position sensor 170 may further include a temperature sensing element 63 capable of sensing an ambient temperature. The temperature sensing element 63 may output a temperature sensing signal Ts according to a result of measuring the temperature around the position sensor 170 to the driver 62 . For example, the temperature sensing element 63 may be a thermistor.

In FIG. 11A , the temperature sensing element 63 may be included in the position sensor 170 , but is not limited thereto. In another embodiment, the temperature sensing element may be provided separately from the position sensor 170 , and may be disposed or mounted on the circuit board 190 of the lens driving device 100 or the circuit board 800 of the camera module 200 . and may be electrically connected to the circuit board 190 or 800 .

The driver 62 may output a driving signal dV for driving the Hall sensor 61 and a driving signal Id1 for driving the shape memory alloy member 310 .

For example, using data communication using a protocol, for example, I2C communication, the driver 62 receives the clock signal SCL, the data signal SDA, and the power signal VDD and GND from the controllers 830 and 780. can receive

The driver 62 may generate a driving signal dV for driving the Hall sensor 61 and a driving signal Id1 for driving the shape memory alloy member 310 .

For example, the position sensor 170 includes first and second terminals for receiving the power signals VDD and VSS, third and fourth terminals for transmitting and receiving the clock signal SCL and the data signal SDA, and It may include fifth to seventh terminals for providing driving signals to the shape memory alloy members 310 and 320 .

Also, the circuit board 190 may be electrically connected to first to seventh terminals (not shown) of the position sensor 170 . The circuit board 190 may include first to third pads 9A to 9C electrically connected to fifth to seventh terminals of the position sensor 170 .

In addition, the driver 62 receives the output (VH) of the Hall sensor 61, using a data communication using a protocol, for example, I2C communication, related to the output (VH) of the Hall sensor 61 The data signal SDA may be transmitted to the controllers 830 and 780 .

In addition, the driver 62 receives the temperature sensing signal Ts measured by the temperature sensing element 63, and controls the temperature sensing signal Ts using data communication using a protocol, for example, I2C communication. It can be transmitted to (830, 780).

The controllers 830 and 780 may perform temperature compensation on the output VH of the Hall sensor 61 based on a change in ambient temperature measured by the temperature sensing element 63 of the position sensor 170 .

11B is a block diagram of a position sensor 170B according to another exemplary embodiment.

The position sensor 170B of FIG. 11B is a modified example of the position sensor 170A of FIG. 11A , and may further include a resistance measuring unit 64 .

The resistance measuring unit 64 may measure the resistance of the shape memory alloy member 310 and transmit the measured result RV to the driver 62 . For example, the resistance measuring unit 64 may detect a voltage across both ends of the shape memory alloy member 310 or a current flowing through the shape memory alloy member 310 and output a detected result (eg, a detected current or a detected voltage). .

Alternatively, in another embodiment, the resistance measuring unit 64 may convert the detected result into a resistance value and output the resistance value to the driver 62 .

The driver 62 receives the output RV of the resistance measuring unit 64, and using data communication using a protocol, for example, I2C communication, to the output RV of the resistance measuring unit 62 The related data signal SDA may be transmitted to the controllers 830 and 780 .

The controllers 830 and 780 may generate, obtain, or calculate the resistance value of the shape memory alloy member 310 by using the data regarding the output RV of the resistance measuring unit 64 received from the position sensor 170A. can

In FIG. 11B , the resistance measuring unit 64 is implemented to be mounted on the position sensor 170A or included in the position sensor 170A, but is not limited thereto. In another embodiment, the resistance measuring unit 64 may be provided separately from the position sensor 170A, and disposed on the circuit board 190 of the lens driving device 100 or the circuit board 800 of the camera module 200 . Or it may be mounted.

The capacitor 195 may be disposed at a corner of the housing 140 . For example, the capacitor 195 may be disposed on the second seating portion 17b of the housing 140 . The capacitor 195 may be disposed or mounted on the first surface 19a of the circuit board 190 , and may be electrically connected to the circuit board 190 .

The capacitor 195 may be in the form of a chip, and may include a first terminal electrically connected to one end of the capacitor 195 and a second terminal electrically connected to the other end of the capacitor 195 . The capacitor 195 may be expressed by replacing it with a “capacitive element” or a capacitor.

In another embodiment, the capacitor 195 may be implemented to be included in the circuit board 190 . For example, the circuit board 190 may include a capacitor including a first conductive layer, a second conductive layer, and an insulating layer (eg, a dielectric layer) disposed between the first conductive layer and the second conductive layer.

For example, the capacitor 195 may be electrically connected to the first and second terminals of the position sensor 170 for receiving the power voltages VDD and VSS in parallel.

For example, the capacitor 195 may be electrically connected in parallel to two terminals of the circuit board 190 for providing power voltages VDD and VSS to the first and second terminals of the position sensor 170 . For example, VSS may be a ground voltage GND.

The capacitor 195 may serve as a smoothing circuit for removing a ripple component included in a power voltage (eg, VDD, VSS) provided to the position sensor 170 from the outside, and thereby It can provide a stable and constant power signal.

In addition, the capacitor 195 may prevent an overcurrent caused by noise or ESD of a high frequency component introduced from the outside from being applied to the position sensor 170 , and calibration of the displacement of the bobbin 110 due to the overcurrent ) value from being reset can be prevented.

For example, the capacitance (or capacitance) of the capacitor 195 may be 0.1 [micro] to 2.5 [micro]. For example, the capacitance of the capacitor 195 may be 2.2 [µF].

Alternatively, in another embodiment, the capacitance of the capacitor 195 may be 0.5 [㎌] to 2 [㎌]. Alternatively, for example, in another embodiment, the capacitance of the capacitor 195 may be 1 [µF] or more.

When the capacitance of the capacitor 195 is less than 0.1 [㎌], it may be difficult to supply a stable power voltage to the position sensor 170 because the ripple removal effect by the smoothing circuit is reduced. When the capacitance of the capacitor 195 exceeds 2.5 [㎌], the size of the capacitor 195 may increase, and a lot of heat may be generated.

1 , the sensing magnet 180 is disposed on the bobbin 110 , and the position sensor 170 and the circuit board 190 are disposed on the housing 140 , but is not limited thereto.

In another embodiment, the sensing magnet may be disposed on the housing, and the position sensor may be disposed on the bobbin to correspond to or face the sensing magnet, and the bobbin may include a circuit pattern, conductive pattern, or wiring electrically connected to the position sensor and the upper elastic member. can be formed. Alternatively, a circuit board electrically connected to the position sensor and the upper elastic member may be disposed on the bobbin.

In another embodiment, the sensing magnet may be disposed on the bobbin, and the position sensor may be disposed on the base to correspond to or face the sensing magnet in the optical axis direction. In this case, a circuit pattern, a conductive pattern, a terminal, a wiring, or a circuit board electrically connected to the position sensor may be disposed on the base.

The elastic member may be coupled to the housing 140 and the bobbin 110 . For example, the elastic member may include at least one of the upper elastic member 150 and the lower elastic member 160 .

Next, the upper elastic member 150 and the lower elastic member 160 will be described.

5 to 8 , the upper elastic member 150 may be coupled to the bobbin 110 . Also, the lower elastic member 160 may be coupled to the bobbin 110 . For example, the upper elastic member 150 and the lower elastic member 160 are coupled to the bobbin 110 and the housing 140 , and may support the bobbin 110 .

For example, the upper elastic member 150 may be coupled to the upper part, the upper surface, or the upper end of the bobbin 110 and the upper part, the upper surface, or the upper part of the housing 140 . The lower elastic member 160 may be coupled to the lower, lower, or lower end of the bobbin 110 and the lower, lower, or lower end of the housing 140 .

The upper elastic member 150 and the lower elastic member 160 may be implemented as a leaf spring, but is not limited thereto, and may be implemented as a coil spring, a suspension wire, or the like.

The upper elastic member 150 includes a first inner frame 151 coupled to the upper portion, upper surface, or upper end of the bobbin 110 , and a first outer frame 152 coupled to the upper portion, upper surface, or upper end of the housing 140 . , and a first frame connection part 153 connecting the first inner frame 151 and the first outer frame 152 . Here, “inner frame” may be expressed as “inner portion”, and “outer frame” may be replaced with “outer portion”.

The lower elastic member 160 is a second inner frame 161 coupled to the lower, lower, or lower end of the bobbin 110 , and a second outer frame 162 coupled to the lower, lower, or lower end of the housing 140 . , and a second frame connection part 163 connecting the second inner frame 161 and the second outer frame 162 .

At least one of the upper elastic member 150 and the lower elastic member 160 may be divided or separated into two or more. At least one of the separated upper elastic members (or lower elastic members) may include at least one of a first inner frame (or a second inner frame) and a first outer frame (or a second outer frame). Or at least one of the separated upper elastic members (or lower elastic members) is a first inner frame (or second inner frame), a first outer frame (or second outer frame), and a first frame connecting portion (or second 2 frame connection).

For example, the upper elastic member 150 may include a first upper elastic member 150-1, a second upper elastic member 150-2, and a third upper elastic member 150-3 spaced apart from each other. .

In another embodiment, the upper elastic member 150 may include four upper elastic members, the circuit board 190 may include four pads respectively connected to the four upper elastic members, the first member One end of (3A) is connected to the first upper elastic member of the four upper elastic members, the other end of the first member (3A) is connected to the second upper elastic member of the four upper elastic members, the second member One end of (3B) may be connected to a third upper elastic member of the four upper elastic members, and the other end of the second member 3B may be connected to a fourth upper elastic member of the four upper elastic members.

7 illustrates one lower elastic member 160 that is not separated from each other, but is not limited thereto. In another embodiment, the lower elastic member may include a plurality of lower elastic members (eg, lower springs).

In another embodiment, the lower elastic member 160 may include four lower elastic members, and the circuit board 190 may include another four pads connected to the four lower elastic members, respectively, as shown in FIG. One end of the third member 4A of 10a is connected to the first lower elastic member of the four lower elastic members, and the other end of the third member 4A is connected to the second lower elastic member of the four lower elastic members. and one end of the fourth member 4B is connected to the third lower elastic member of the four lower elastic members, and the other end of the fourth member 4B is connected to the fourth lower elastic member of the four lower elastic members. can

In addition, in FIG. 9 , the first shape memory alloy member 310 is electrically connected to the upper elastic member 150 , and the present invention is not limited thereto. In another embodiment, the first shape memory alloy member 310 is divided into three It may be electrically connected to the lower elastic members, or may be electrically connected to the circuit board 190 through the three lower elastic members.

In addition, in FIG. 10A , the first shape memory alloy member 310 is electrically connected to the upper elastic member 150 , and the second shape memory alloy member 320 is electrically connected to the lower elastic member 160A, but is limited thereto. In another embodiment, the second shape memory alloy member 320 may be electrically connected to the upper elastic member 150 , and the first shape memory alloy member 310 may be electrically connected to the lower elastic member 160A. there is.

For example, each of the first to third upper elastic members 150 - 1 to 150 - 3 may include a first outer frame 152 , and the second and third upper elastic members 150 - 2 and 150 . -3) Each may include a first inner frame 151 and a first frame connection part 153 .

For example, the first upper elastic member 150 - 1 includes a first extension portion 8A extending from the first outer frame 151 of the first upper elastic member 150 - 1 toward the circuit board 190 . can do. The first extension portion 8A may be coupled to the first pad 9A of the circuit board 190 by a conductive adhesive or solder, and may be electrically connected to the first pad 9A.

The second upper elastic member 150 - 2 may include a second extension portion 8B extending from the first outer frame 151 of the second upper elastic member 150 - 2 toward the circuit board 190 . there is. The second extension portion 8B may be coupled to the second pad 9B of the circuit board 190 by a conductive adhesive or solder, and may be electrically connected to the second pad 9B.

The third upper elastic member 150 - 3 may include a third extension portion 8B extending from the first outer frame 151 of the third upper elastic member 150 - 3 toward the circuit board 190 . there is. The third extension portion 8C may be coupled to the third pad 9C of the circuit board 190 by a conductive adhesive or solder, and may be electrically connected to the third pad 9C.

The first inner frame 151 of the upper elastic member 150 may be provided with a groove 151a or a hole coupled to the first coupling portion 113 of the bobbin 110, and the first outer frame ( A hole 152a or a groove coupled to the first coupling portion 144 of the housing 140 may be provided in the 152 , and a cut groove may be formed in each of the grooves 151a and 152a, but in another embodiment The cut groove may not be formed.

For example, a hole for coupling with the second coupling part 117 of the bobbin 110 may be provided in the second inner frame 161 of the lower elastic member 160 , and the second outer side of the lower elastic member 160 . A hole for coupling with the second coupling part 147 of the housing 140 may be provided in the frame 162 .

Each of the first frame connection part 153 and the second frame connection part 163 of the upper elastic member 150 and the lower elastic member 160 is bent or curved (or curved) at least once to form a pattern of a certain shape. can be formed The bobbin 110 may be elastically (or elastically) supported by the rising and/or lowering motions in the first direction through a change in the position of the first and second frame connection parts 153 and 163 and micro-deformation.

In order to absorb and buffer the vibration of the bobbin 110 , the lens driving device 100 may further include a damper (not shown) disposed between the upper elastic member 150 and the housing 140 .

For example, a damper (not shown) may be disposed in a space between the first frame connection part 153 of the upper elastic member 150 and the bobbin 110 (or/and the housing 140 ).

Also, for example, the lens driving device 100 further includes a damper (not shown) disposed between the second frame connection part 163 of the lower elastic member 160 and the bobbin 110 (or/and the housing 140 ). You may.

Also, for example, a damper (not shown) may be further disposed between the inner surface of the housing 140 and the outer surface of the bobbin 110 .

Next, the base 210 will be described.

Referring to FIG. 6 , the base 210 may include an opening 101 of the bobbin 110 , and/or an opening 201 corresponding to the opening 140A of the housing 140 , and the cover member 300 . ) and may have a shape corresponding to or coincident with, for example, a rectangular shape.

The base 210 may include a step 211 at the lower end of the outer surface of the base 210 to which the adhesive may be applied when the cover member 300 is adhesively fixed. In this case, the step 211 may guide the cover member 300 coupled to the upper side, and may face the lower end of the side plate 302 of the cover member 300 . An adhesive member and/or a sealing member may be disposed or applied between the lower end of the side plate 302 of the cover member 300 and the step 211 of the base 210 .

The base 210 may be disposed under the bobbin 110 and the housing 140 .

For example, the base 210 may be disposed under the lower elastic member 160 .

A protrusion 216 corresponding to the guide groove 148 of the housing 140 may be provided at a corner of the upper surface of the base 210 . For example, the protrusion 216 may have a polygonal column shape protruding from the upper surface of the base 210 so as to be perpendicular to the upper surface of the base 210 , but is not limited thereto. The protrusion 216 may be replaced with a “pillar”.

The protrusion 216 may be inserted into the guide groove 148 of the housing 140 , and may be fastened or coupled to the guide groove 148 by an adhesive member (not shown) such as epoxy or silicone.

In order to prevent the lower or lower end of the bobbin 210 from directly colliding with the upper surface of the base 210 when an external shock occurs, the base 210 may include a stopper 23 protruding from the upper surface, and the base 210 ) of the stopper 23 may be disposed to correspond to the protrusion 216 of the base 210, but is not limited thereto.

The base 210 may include a seating groove 210a for the lower end of the circuit board 190 to be seated on an outer surface corresponding to or opposite to the side of the housing 140 on which the circuit board 190 is disposed. The seating groove 210a of the base 210 may have a structure recessed from the outer surface of the base 210 .

For example, the terminals B1 to B6 of the circuit board 190 may be disposed at the lower end of the second surface 19b of the circuit board 190 , and may be located in the seating groove 210a of the base 210 . there is.

For example, a protrusion 36 for supporting the circuit board 190 may be formed in the seating groove 210a of the base 210 , and in another embodiment, the protrusion may be omitted.

The protrusion 36 of the base 210 may have a shape protruding from the bottom of the seating groove 210a, and may support the extension S2 of the circuit board 190 (eg, the lower end of the extension S2). However, the present invention is not limited thereto.

Referring to FIG. 7 , the circuit board 190 may include a body portion S1 and an extension portion S2 positioned under the body portion S1 . The body portion S1 may be expressed by replacing the “upper portion”, and the extension portion S2 may be expressed by replacing the “lower portion”. The extension portion S2 may extend downward from the body portion S1 .

For example, the terminals B1 to B6 of the circuit board 190 may be disposed on the extension portion S2 , but the present invention is not limited thereto. The body portion S1 may have a protruding shape based on the side surface of the extension portion S2 .

Next, the cover member 300 will be described.

The cover member 300 may accommodate the bobbin 110 and the housing 140 in an accommodating space formed together with the base 210 .

The cover member 300 has an open lower portion, and may be in the form of a box including an upper plate 301 and side plates 302 , and the lower ends of the side plates 302 of the cover member 300 have a base 210 . ) can be combined with the upper part. The shape of the upper plate of the cover member 300 may be a polygon, for example, a quadrangle or an octagon, and an opening 303 for exposing a lens (not shown) to external light may be provided in the upper plate 301 . The opening 303 may be a through hole passing through the upper plate 301 .

The shape memory alloy member 310 may include a shape memory alloy (SMA). A shape-memory alloy is an alloy that returns to its original memorized shape at a specific temperature even if it is deformed into a different shape.

The shape memory alloy member 310 may be an alloy including at least one of Ti, Ni, Cu, Fe, Au, Zn, Mn, Ag, or Cd.

The shape memory alloy member 310 may change in resistance and length by energizing or de-energizing.

12 is a view for explaining the relationship between the temperature, resistance, and length of the shape memory alloy member 310 .

Referring to FIG. 12A , the resistance of the shape memory alloy member 310 at a low temperature (eg, room temperature) may have a high resistance value. In this case, the shape memory alloy member 310 may have a first length L1 .

Referring to FIG. 12B , when a driving signal (eg, a driving current or a driving voltage) is applied to the shape memory alloy member 310 , the temperature of the shape memory alloy member 310 increases, and the driving temperature (eg, The length of the shape-memory alloy member 310 may decrease at 100° C. to 110° C., and in this case, the shape-memory alloy member 310 may have a second length L2 that is smaller than the first length L1.

In this way, the shape memory alloy member 310 may be expanded or contracted by the driving signal, and the AF moving unit (eg, the bobbin 110 ) coupled to the shape memory alloy member 310 moves in the first direction. can By controlling the strength of the driving signal applied to the shape memory alloy member 310 , the degree of expansion or contraction of the shape memory alloy member 310 may be adjusted, thereby performing an auto-focusing function.

For example, since the shape memory alloy member 310 has a strong hysteresis characteristic, the driving signal provided to the shape memory alloy member 310 may be a pulse width modulation (PWM) signal in order to minimize this. As a result, current consumption can be reduced and response speed can be increased.

The shape memory alloy member 310 may connect the AF moving unit (eg, the bobbin 110 ) and the fixed unit. For example, one end of the shape memory alloy member 310 may be coupled to the bobbin 110 , and the other end of the shape memory alloy member 310 may be coupled to a fixing unit. In this case, the fixing part is the housing 140 , a portion of the upper elastic member 150 coupled to the housing 140 (eg, the first outer frame 152 ), the circuit board 190 coupled to the housing 140 , or It may be at least one of the bases 210 .

For example, the shape memory alloy member 310 may be a conductive member formed of a conductive material.

For example, the shape memory alloy member 310 may be in the form of a wire or a plate. The shape memory alloy member 310 may include a first member 3A and a second member 3B.

Referring to FIG. 9 , at least a portion of the first member 3A may be supported or caught by the first protrusion 15A of the bobbin 110 . For example, the middle region or the middle portion of the first member 3A may be in contact with, attached to, or fixed to the lower portion of the first protrusion 15A of the bobbin 110 .

At least a portion of the second member 3B may be supported, coupled to, or caught on the second protrusion 16A of the bobbin 110 . For example, the middle region or the middle portion of the second member 3B may be in contact with, attached to, or fixed to the lower portion of the second protrusion 16A of the bobbin 110 .

One end 2A of the first member 3A may be coupled to the first upper elastic member 150-1, and the other end 2B of the first member 3A is the second upper elastic member 150-2. can be coupled to One end 2C of the second member 3B may be coupled to the third upper elastic member 150-3, and the other end 2D of the second member 3B is the second upper elastic member 150-2. can be coupled to

For example, at least a portion of each of the first member 3A and the second portion 2B may be coupled or fixed to the housing 140 .

The shape memory alloy member 310 may be electrically connected to the upper elastic member 150 .

For example, one end 2A of the first member 3A may be coupled to the first outer frame 152 of the first upper elastic member 150-1 by means of a conductive adhesive or solder. The other end 2B of the first member 3A may be coupled to one region of the first outer frame 152 of the second upper elastic member 150 - 2 by a conductive adhesive or solder.

For example, one end 2C of the second member 3B may be coupled to the first outer frame 152 of the third upper elastic member 150-3 by means of a conductive adhesive or solder. The other end 2D of the second member 3B may be coupled to another region of the first outer frame 152 of the second upper elastic member 150 - 2 by means of a conductive adhesive or solder.

From the position sensor 170 to the first member 3A through the first and second pads 9A and 9B and the first and second upper elastic members 150-1 and 150-2 of the circuit board 190 A first driving signal may be provided and positioned through the second and third pads 9B and 9C and the second and third upper elastic members 150 - 2 and 150 - 3 of the circuit board 190 . A second driving signal may be provided from the sensor 170 to the second member 3B. In this case, the first driving signal and the second driving signal may be the same single signal, but the present invention is not limited thereto. In another embodiment, the first driving signal and the second driving signal are used to adjust the tilt value (or tilt degree) of the lens. may be a separate independent signal.

In the embodiment, since the shape memory alloy member 310 is electrically connected to the circuit board 190 by the first to third upper elastic members 150-1 to 150-3, the shape memory alloy member 310 and The reliability of the electrical connection between the first to third upper elastic members 150-1 to 150-3 may be improved, disconnection and poor coupling may be prevented, and the shape memory alloy member 310 and the circuit board 190 may be formed. It is possible to improve the reliability of the electrical connection between the two.

For example, the first member 3A and the second member 3B are connected to the first to third pads of the circuit board 190 by the first to third upper elastic members 150-1 to 150-3. 9A to 9B) may be connected in parallel. For example, the second pad 9B may correspond to a common terminal or a ground terminal.

The AF moving unit according to the embodiment shown in FIG. 9 may be driven in one direction. Here, the unidirectional driving refers to moving the AF moving unit in one direction, for example, in an upward direction (eg, in an upward direction (+Z-axis direction)) based on the initial position of the AF moving unit.

For example, the initial position of the AF moving unit (eg, bobbin 110 ) may be the initial position of the AF moving unit (eg, bobbin) in a state in which a driving signal is not applied to the shape memory alloy member 310 , and the upper As the elastic member 150 and the lower elastic member 160 are elastically deformed only by the weight of the AF moving part, it may be a position at which the AF moving part is placed.

In addition, the initial position of the AF moving unit (eg, the bobbin 110 ) is determined when gravity acts in the direction from the bobbin 110 to the base 210 , or conversely, when gravity acts in the direction from the base 210 to the bobbin 110 . It may be a position at which the AF moving unit is placed.

For example, the AF moving unit may include the bobbin 110 elastically supported by the upper elastic member 150 and the lower elastic member 160 , and components mounted on the bobbin 110 to move together with the bobbin 110 . For example, the AF moving unit may include at least one of the bobbin 110 , the sensing magnet 180 , and the balancing magnet 185 , and when the lens module 400 is mounted, it may include the lens module 400 .

Or, for example, in the initial position, even if a driving signal is applied to the shape memory alloy member 310 , the driving force of the shape memory alloy member 310 by the driving signal is applied to the pressing force by the upper elastic member 150 and the lower elastic member 160 . It may be the position of the AF moving unit in a state in which the AF moving unit does not move because it does not exceed .

Since the shape memory alloy member 310 does not have a constant tension or pressing force on the AF moving unit in the initial state, vibration or noise may be generated due to shaking of the AF moving unit. The pressing force of the upper elastic member 150 and the lower elastic member 160 may be set so that the bobbin 110 comes into contact with the base 210 . Due to this, the embodiment may be resistant to vibration and noise, and reliability of AF driving may be improved.

In the unidirectional driving, the bobbin 110 may be driven when the force by the shape memory alloy member 310 to which the driving signal is supplied exceeds the pressing force of the elastic members 150 and 160 . In the initial position, the lower, lower, or lower end (eg, lower stopper) of the bobbin 110 may be in contact with the upper surface of the base 210 .

For example, the diameter of the shape memory alloy member (310: 3A, 3B) may be 10 [um] ~ 150 [um]. Or, for example, the diameter of the shape memory alloy member (310: 3A, 3B) may be 20 [um] ~ 90 [um].

When the diameter of the shape memory alloy member 310 (3A, 3B) exceeds 150 [um], the time for contraction and expansion is too long, so that the driving speed and fixing time of the lens driving device may be long. In addition, when the diameter of the shape memory alloy member (310: 3A, 3B) is less than 10 [um], the impact may be weak and reliability may deteriorate. The description of the diameter of the shape-memory alloy member 310 may be applied to the shape-based alloy member 320 to be described later.

The shape memory alloy member 310 may include two or more members. In the embodiment of FIG. 9 , two members 3A and 3B in contact with the protrusions formed on the two outer surfaces of the bobbin 110 facing each other are illustrated, but the present invention is not limited thereto, and another embodiment of the bobbin Additional projections may be formed on the other two outer surfaces facing each other of 110 , and another embodiment may further include two additional members contacting each of the additional projections of the bobbin.

For example, the first resonant frequency of the AF moving unit may be 30 [Hz] to 400 [Hz]. Alternatively, for example, the first resonant frequency of the AF moving unit may be 30 [Hz] to 200 [Hz].

In this case, the first resonance frequency may be a first resonance frequency related to mechanical vibration of the AF moving unit according to the AF driving. Alternatively, for example, the first resonant frequency may be a first resonant frequency according to a frequency response characteristic of a drive signal supplied to the shape memory alloy member 310 and an output of the position sensor 170 . In this case, the AF moving unit may be a case in which the lens module 400 is coupled to the bobbin.

In the SMA actuator according to the comparative example, the position or displacement of the AF moving part (eg, bobbin) is detected by measuring the resistance value of the shape memory alloy. To this end, in the comparative example, calibration is performed on the position (or displacement) of the bobbin and the resistance value of the shape memory alloy. For example, the resistance value of the shape memory alloy may be measured by supplying a driving signal having a driving frequency of several tens of KHz to the shape memory alloy, measuring the current value of the shape memory alloy, and using the measured current value.

However, since the temperature of the shape memory alloy must be about 100 to 110 degrees in order for the shape memory alloy to contract or expand, a lot of heat may be generated in the shape memory alloy when the SMA actuator is driven. The heat generated in this way may change or change the resistance value of the shape memory alloy, the detected resistance value of the shape memory alloy may generate an error or error, and the accuracy or reliability of the position sensing of the AF moving unit may be lowered. there is.

In addition, since there is no accurately measured reference temperature in the comparative example, it is not possible to determine how much offset is generated with respect to the displacement of the AF moving part measured using the detected resistance value. Also, in the comparative example, the resistance value of the shape memory alloy needs to be measured in real time to detect the displacement of the AF moving part, and the resistance value of the shape memory alloy may change with changes in ambient temperature. In addition, since a driving signal having a driving frequency of several tens of KHz is used, a change in the resistance value of the shape memory alloy may occur due to the skin effect, which may cause an error or error in the detection value of the resistance of the shape memory alloy. can

The embodiment may include the following configuration in order to eliminate this problem and to improve the accuracy of temperature compensation according to changes in ambient temperature.

In an embodiment, the position sensor 170 and the sensing magnet 180 may be used to drive the AF moving unit using the shape memory alloy members 310 and 320 and to sense the displacement or position of the AF moving unit. The position sensor 170 illustrated in FIG. 11A may generate an output according to a result of sensing the strength of the magnetic field of the sensing magnet 180 according to the movement of the AF moving unit.

The position sensor 170 of FIG. 11A may include a temperature sensing element 63 , and may measure a temperature of the position sensor 170 , a temperature of a lens driving device, or an ambient temperature, and a temperature sensing signal Ts ) can be printed.

As described above, the controllers 830 and 780 may compensate an output value (or an output-related code value) of the position sensor 170 based on the ambient temperature measured by the temperature sensing element 63 .

For example, the controllers 830 and 780 may include a compensation algorithm for temperature compensation. For example, the controllers 830 and 780 may include a memory for storing a temperature compensation algorithm. For example, the temperature compensation algorithm may include a quadratic or cubic equation. For example, the temperature compensation algorithm may compensate for at least one of a displacement of the bobbin 110 or a slope and an offset of an equation related to the output of the position sensor 170 .

14 illustrates a temperature compensation method according to an embodiment.

Referring to FIG. 14 , the controllers 830 and 780 may generate a correlation between the displacement of the AF moving unit and the output of the position sensor 170 matching the displacement through calibration, and store the correlation.

For example, the controllers 830 and 780 may include a lookup table that stores code values related to the output of the position sensor 170 corresponding to or matching the target position (or displacement) of the AF moving unit.

The controllers 830 and 780 receive a target value (code value) of the output of the position sensor 170 corresponding to or matching the target position of the AF moving unit (eg, the bobbin 110) from the lookup table (S110) .

The controllers 830 and 780 may generate a driving signal for driving the shape memory alloy 310 or 320 or generate a control signal for generating a driving signal based on the target value ( S120 ).

The shape memory alloy 310 or 320 is driven by the driving signal (or control signal) generated by the controllers 830 and 780 , so that the AF moving unit may be moved in the optical axis direction.

The controllers 830 and 780 receive data related to the output of the position sensor 170 or the output of the position sensor 170 according to the movement result of the AF moving unit (S130).

Also, the controllers 830 and 780 receive the ambient temperature measured by the temperature sensing element 63 and generate a correction value (or compensation value) based on the received ambient temperature ( S140 ).

Next, the controllers 830 and 780 correct the output of the position sensor 170 or data (or code value) related to the output of the position sensor 170 based on the correction value.

15 illustrates a temperature compensation method according to another exemplary embodiment.

Referring to FIG. 15 , steps S210 to S230 apply or apply the descriptions of steps S110 to S130 of FIG. 14 . The position sensor 170A shown in FIG. 11B may be applied to the embodiment of FIG. 15 .

The controllers 830 and 780 receive the ambient temperature measured by the temperature sensing element 63 . In addition, the controllers 830 and 780 receive data regarding the output RV of the resistance measuring unit 64 and obtain a resistance value of the shape memory alloy member by using the received data ( S240 ).

Next, a correction value is generated based on the ambient temperature and the resistance value measured by the temperature sensing element 63 (S250). The resistance value may be a measure for measuring the ambient temperature, and the ambient temperature may be measured using the resistance value.

The controllers 830 and 780 may store a correlation between a resistance value (or a detected current or a detected voltage of the resistance measuring unit 64 ) of the shape memory alloy member 310 and a temperature corresponding thereto.

For example, the controllers 830 and 780 may compensate for the resistance value of the shape memory alloy member 310 using the ambient temperature measured by the temperature sensing element 63 , and use the compensated resistance value to set the target value. The correction value for correction may be generated.

Alternatively, for example, the controllers 830 and 780 may compensate or correct the ambient temperature measured by the temperature sensing element 63 using the resistance value of the shape memory alloy member 310 , and the compensated or corrected ambient temperature may be used to generate the correction value for correcting the target value.

Next, the controllers 830 and 780 may correct the output of the position sensor 170A or data (code values) related to the output based on the correction value.

14 and 15, the output value of the position sensor 170 is corrected using the correction value, but in another embodiment, the target value (or code value) of the output of the position sensor 170 stored in the lookup table using the correction value can also be corrected.

10A is a perspective view of a partial configuration of a lens driving device according to another exemplary embodiment, and FIG. 10B is a shape memory alloy member 320 ( 4A, 4B), a lower elastic member 160A, and a circuit board 190-1 of FIG. 10A . ) represents the electrical connection.

10A and 10B , the lens driving apparatus according to another exemplary embodiment may further include shape memory alloy members 320 ( 4A and 4B). Hereinafter, the shape memory alloy member 310 of FIG. 1 is referred to as a “first shape memory alloy member”, and the shape memory alloy member 320 of FIGS. 10A and 10B is referred to as a “second shape memory alloy member”.

The lower elastic member 160A may include first to third lower elastic members 160-1 to 160-3. The first to third lower elastic members 160-1 to 160-3 may be the same as or similar to the shapes of the first to third upper elastic members 150-1 to 150-3, but are not limited thereto. .

In another embodiment, both may have different shapes. For example, the lengths of the extensions 7A to 7C of the first to third lower elastic members 160-1 to 160-3 are equal to the lengths of the extensions of the first to third upper elastic members 150-1 to 150-3. It may be less than the length of (8A to 8C).

Descriptions of the first to third upper elastic members 150-1 to 150-3 may be applied or analogously applied to the first to third lower elastic members 160-1 to 160-3.

The circuit board 190A may further include fourth to sixth pads 10A and 10C.

Also, for example, a third protrusion 15B that protrudes in a horizontal direction and is spaced apart from the first protrusion 15A may be formed on the first outer surface of the bobbin 110 . In addition, a fourth protrusion 16B (refer to FIG. 3A ) protruding in the horizontal direction and spaced apart from the second protrusion 16A may be formed on the second outer surface of the bobbin 110 .

For example, the third protrusion 15B and the fourth protrusion 16B may be disposed to be more adjacent to the upper surface of the bobbin 110 than the lower surface of the bobbin 110 . For example, the third protrusion 15B and the fourth protrusion 16B may correspond to, face each other, or overlap each other in the horizontal direction. This is to allow the shape memory alloy member 310 to support the bobbin 110 in a balanced way.

In addition, the third protrusion 15B may be positioned higher than the first protrusion 15A, and the fourth protrusion 16B may be positioned higher than the second protrusion 16A. In the optical axis direction, the third protrusion 15B may correspond to, face, or overlap the first protrusion 15A, and in the optical axis direction, the fourth protrusion 16B may correspond to, face, or overlap the first protrusion 16A. can be

In addition, each of the third protrusion 15B and the fourth protrusion 16B may include a curved surface convex in an upward direction. For example, each of the third protrusion 15B and the fourth protrusion 16B may have a hemispherical, semi-elliptical, or dome shape convex from the lower surface to the upper surface of the bobbin 110 . This is by making the portion where the shape memory alloy members 320 (4A and 4B) contact the curved or convex surfaces of the third protrusion 15B and the fourth protrusion 16B, and thus the protrusions 15B and 16B and the shape memory alloy member. Friction force between ( 320 : 4A and 4B ) may be reduced, and thus, disconnection of the shape memory alloy members ( 320 : 4A and 4B) may be prevented.

In addition, a groove 108 in which at least a portion (eg, a middle portion) of the shape memory alloy member 310 ( 3A, 3B) is disposed may be formed on the convex curved surface of each of the third protrusion 15B and the fourth protrusion 16B. there is. By forming the groove 108, it is possible to prevent the shape memory alloy members 320 (4A, 4B) from being separated from the protrusions 15B and 16B, and thereby the shape memory alloy members 320 (4A and 4B) and the bobbin. It is possible to improve the binding force of (110).

Alternatively, for example, a lower portion of each of the third protrusion 15B and the fourth protrusion 16B may be flat, but is not limited thereto.

For example, the separation distance between the first protrusion 15A (or the second protrusion 16A) and the third protrusion 15B (or the fourth protrusion 16B) is the first protrusion 15A (or the second protrusion 16A). )) and the lower surface of the bobbin 110 may be greater than the separation distance.

Or, for example, the separation distance between the first protrusion 15A (or the second protrusion 16A) and the third protrusion 15B (or the fourth protrusion 16B) is the third protrusion 15B (or the fourth protrusion ( 16B)) and the upper surface of the bobbin 110 may be greater than the separation distance.

The second shape memory alloy member 320 may include a third member 4A and a fourth member 4B.

Referring to FIGS. 10A and 10B , at least a portion of the third member 4A may be supported, coupled to, or caught on the third protrusion 15B of the bobbin 110 . For example, the middle region or the middle portion of the third member 4A may be in contact with, attached to, or fixed to the upper portion of the third protrusion 15B of the bobbin 110 .

At least a portion of the fourth member 4B may be supported, coupled to, or caught on the fourth protrusion 16B of the bobbin 110 . For example, the middle region or the middle portion of the fourth member 4B may be in contact with, attached to, or fixed to the upper portion of the fourth protrusion 16B of the bobbin 110 .

One end 28A of the third member 4A may be coupled to the first lower elastic member 160-1, and the other end 28B of the third member 4A is the second lower elastic member 160-2. can be coupled to One end 28C of the fourth member 4B may be coupled to the third lower elastic member 160-3, and the other end 28D of the fourth member 4B is the second upper elastic member 150-2. can be coupled to

For example, at least a portion of each of the third and fourth members 4A and 4B may be coupled or fixed to the base 210 .

The second shape memory alloy member 320 may be electrically connected to the lower elastic member 160A.

For example, one end 28A of the third member 4A may be coupled to the second outer frame 162-1 of the first lower elastic member 160-1 by means of a conductive adhesive or solder. The other end 28B of the third member 4A may be coupled to one region of the second outer frame 162-1 of the second lower elastic member 160-2 by means of a conductive adhesive or solder.

For example, one end 28C of the fourth member 4B may be coupled to the second outer frame 162-1 of the third lower elastic member 160-3 by means of a conductive adhesive or solder. The other end 28D of the fourth member 4B may be coupled to another region of the second outer frame 162-1 of the second lower elastic member 160-2 by means of a conductive adhesive or solder.

From the position sensor 170 to the third member 4A through the fourth and fifth pads 10A and 10B and the first and second lower elastic members 160-1 and 160-2 of the circuit board 190 A third driving signal may be provided and positioned through the fifth and sixth pads 10B and 10C and the second and third lower elastic members 160 - 2 and 160 - 3 of the circuit board 190 . A fourth driving signal may be provided from the sensor 170 to the fourth member 4B. The third driving signal and the fourth driving signal may be the same signal, but the present invention is not limited thereto, and in another embodiment, both may be different independent signals.

In the embodiment, since the shape memory alloy member 320 is electrically connected to the circuit board 190 by the first to third lower elastic members 160-1 to 160-3, the shape memory alloy member 320 and The reliability of the electrical connection between the first to third lower elastic members 160-1 to 160-3 is improved, disconnection and poor coupling can be prevented, and the shape memory alloy member 320 and the circuit board 190 are improved. It is possible to improve the reliability of the electrical connection between the two.

For example, by the first to third lower elastic members 160-1 to 160-3, the third sub-fold 4A and the fourth member 4B are connected to the fourth to sixth pads ( 10A to 10C) may be connected in parallel. For example, the fifth pad 10B may correspond to a common terminal or a ground terminal.

The AF moving unit according to the embodiment shown in FIGS. 10A and 10B may be driven in both directions. Here, the bidirectional driving refers to the movement of the AF moving unit in both directions (eg, upward or downward) based on the initial position of the AF moving unit.

For bidirectional driving, elastic force by the upper elastic member 150 and the lower elastic member 160 supporting the AF moving unit in a state where a driving signal is not supplied to the first and second shape memory alloy members 310 and 320 or The AF moving unit may be spaced apart from the base 210 by a predetermined distance in the optical axis direction by the pressing force. In this case, the separation distance between the base 210 and the lowermost end of the bobbin 110 may be greater than or equal to the maximum movement distance (or maximum stroke) of the AF moving unit in the downward direction.

13 illustrates an operation section of the first and second shape memory alloy members 310 and 320 for bidirectional driving. In the graph of FIG. 13 , the X-axis represents a code value related to the output of the position sensor or resistance values of the first and second shape memory alloy members 310 and 320 . The Y-axis represents the displacement of the AF moving part. For example, in the graph, the origin (0, 0) may be the initial position of the AF moving unit.

Referring to FIG. 13 , the displacement (or movement position) of the AF moving unit may include a first section M1 and a second section M2 with respect to the initial position.

The first section M1 may be a movement section of the bobbin 110 in the upward direction (or forward) based on the initial position. The first section M1 may correspond to the first quadrant in the graph of FIG. 13 .

Also, the second section M2 may be a movement section of the bobbin 110 in a downward direction (or rearward) with respect to the initial position. The second section M2 may correspond to the third quadrant in the graph of FIG. 13 .

For example, the distance (or length) of the first section M1 may be greater than the distance (or length) of the second section M2 .

By driving the first shape memory alloy member 310 , the AF moving unit may be moved in the first section M1 . Also, by driving the second shape memory alloy member 320 , the AF moving unit may be moved in the second section M2 .

For example, only the first shape memory alloy member 310 may be driven in the first section M1 , and only the second shape memory alloy member 320 may be driven in the second section M2 .

For example, in the first section M1 , the first driving signal may be supplied to the first member 3A and the second driving signal may be supplied to the second member 3B. Also, in the first section M1 , a driving signal may not be supplied to each of the third member 4A and the fourth member 4B.

On the other hand, for example, in the second section M2 , the third driving signal may be supplied to the third member 4A and the fourth driving signal may be supplied to the fourth member 4B. Also, in the second section M2 , a driving signal may not be supplied to each of the first member 3A and the second member 3B.

Reducing the temperature of the shape memory alloy member (eg, increasing the length of the shape memory alloy) compared to increasing the temperature of the shape memory alloy member (eg, reducing the length of the shape memory alloy) is a response characteristic (eg, increasing the length of the shape memory alloy) response speed) is slow.

In another embodiment, in order to increase the AF driving speed, when the AF moving part (eg, the bobbin 110) is lowered, the second shape memory alloy member ( 320) may be supplied with a driving signal.

For example, when the AF moving unit (eg, the bobbin 110) is lowered in the first section M1 and the second section M2, the first shape memory alloy member 310 increases in length, and the second By reducing the length of the shape memory alloy member 320 , the response speed may be improved. For example, when the AF moving unit (eg, the bobbin 110) is lowered in the first section M1 and the second section M2, the first member 3A, the second member 3B, and the third member ( 4A), and each of the fourth member 4B can be supplied with a drive signal, and by controlling each drive signal, it is possible to improve the response speed with respect to the movement of the AF moving unit to the drive signal.

During AF driving, when the AF moving unit (eg, the bobbin 110 ) collides with or comes into contact with the base 210 or the cover member 300 , oscillation may occur, which deteriorates reliability of AF driving.

Therefore, in the embodiment, in order to prevent such oscillation, the change in length of the shape memory alloy member 310 or 320 may be limited when the AF is driven.

For example, within the range of the entire stroke section (or movement section) of the AF moving unit, the length of the shape memory alloy member 310 or 320 may be converted within 2% of the total length of the shape memory alloy member 310 or 320 there is.

For example, the entire length of the shape memory alloy member 310 or 320 is coupled to the second upper elastic member 150-2 at one end of the first member 3A coupled to the first upper elastic member 150-1. It may be the length to the other end of the first member 3A. The other members 3B, 4A, and 4B may also define an overall length by applying the above-described definition of the first member 3A.

For example, the difference between the overall length of the shape memory alloy member 310 or 320 at the initial position and the overall length of the shape memory alloy member 310 or 320 at the maximum stroke point of the AF moving part is the shape memory alloy member 310 or 320 . 320) may be less than or equal to 2% of the total length.

The stroke of the AF moving part can be limited by software. For example, when the target output (target code) of the position sensor 170 that matches the displacement of the AF moving unit obtained through calibration for AF driving is -1023 to +1023, the bobbin 110 moves to the base 210 during AF driving. ) or the cover member 300 , the controllers 830 and 780 may limit some codes of the target output.

For example, the controllers 830 and 780 may use only some codes (eg, -950 to +950) among -1023 to +1023. For example, the M3 section may be an actual movement section of the AF moving unit for preventing oscillation, thereby improving the linearity of the correlation between the displacement of the AF moving unit and the output of the position sensor 170 , thereby improving AF accuracy. can be improved

For example, the reference separation distance between the stopper of the bobbin 110 and the base 210 (or the cover member 300 ) according to the stroke limitation of the AF moving unit described above may be 10 [um] or more. Or, for example, the reference separation distance may be 10 [um] ~ 100 [um]. Or, for example, the reference separation distance may be 10 [um] ~ 30 [um].

At this time, the reference separation distance is the distance between the upper stopper (or the uppermost end of the bobbin) and the cover member 300 at the highest position of the stroke-limited bobbin 110, or the lower stopper (or the lowermost end of the bobbin) at the lowest position of the stroke-limited bobbin 110 . ) and the distance between the base 210 may be.

Meanwhile, the lens driving apparatus according to the above-described embodiment may be used in various fields, for example, a camera module or an optical device.

For example, the lens driving device 100 according to the embodiment forms an image of an object in space using reflection, refraction, absorption, interference, diffraction, etc., which are characteristics of light, and aims to increase the visual power of the eye, It may be included in an optical instrument for the purpose of recording and reproducing an image by a lens, or for optical measurement, propagation or transmission of an image, and the like. For example, the optical device according to the embodiment is a mobile phone, a mobile phone, a smart phone, a portable smart device, a digital camera, a laptop computer, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP) ), navigation, etc., but is not limited thereto, and any device for taking an image or photo is possible.

16 is an exploded perspective view of the camera module 200 according to the embodiment.

Referring to FIG. 16 , the camera module 200 includes a lens module 400 , a lens driving device 100 , an adhesive member 612 , a filter 610 , a circuit board 800 , an image sensor 810 , and a connector. (connector, 840).

The lens module 400 may include a lens and/or a lens barrel, and may be mounted on the bobbin 110 of the lens driving device 100 .

For example, the lens module 400 may include one or more lenses and a lens barrel accommodating the one or more lenses. However, one configuration of the lens module is not limited to the lens barrel, and any holder structure capable of supporting one or more lenses may be used. The lens module may be coupled to the lens driving device 100 and move together with the lens driving device 100 .

For example, the lens module 400 may be screw-coupled to the lens driving device 100 as an example. As an example, the lens module 400 may be coupled to the lens driving device 100 by an adhesive (not shown). Meanwhile, light passing through the lens module 400 may pass through the filter 610 to be irradiated to the image sensor 810 .

The adhesive member 612 may couple or attach the base 210 of the lens driving device 100 to the circuit board 800 . For example, the adhesive member 612 may be an epoxy, a thermosetting adhesive, or an ultraviolet curable adhesive.

The filter 610 may serve to block light of a specific frequency band in light passing through the lens barrel 400 from being incident on the image sensor 810 . The filter 610 may be an infrared cut filter, but is not limited thereto. In this case, the filter 610 may be disposed to be parallel to the x-y plane.

In this case, the infrared cut filter may be formed of a film material or a glass material. As an example, the infrared filter may be formed by coating an infrared blocking coating material on a flat optical filter such as a cover glass for protecting an imaging surface or a cover glass.

The filter 610 may be disposed under the base 210 of the lens driving device 100 .

For example, the base 210 may include a seating portion on the lower surface of which the filter 610 is mounted. In another embodiment, a separate sensor base for mounting the filter 610 may be provided.

The circuit board 800 may be disposed under the lens driving device 100 , and the image sensor 810 may be mounted on the circuit board 800 . The image sensor 810 may receive an image included in light incident through the lens driving apparatuses 100 and 1000 and convert the received image into an electrical signal.

The image sensor 810 may be positioned so that the lens module 400 and the optical axis coincide. Through this, the image sensor may acquire the light passing through the lens module 400 . The image sensor 810 may output the irradiated light as an image. The image sensor 810 may be, for example, a charge coupled device (CCD), a metal oxide semi-conductor (MOS), a CPD, and a CID. However, the type of the image sensor is not limited thereto.

The filter 610 and the image sensor 810 may be spaced apart to face each other in the first direction.

The connector 840 is electrically connected to the circuit board 800 and may include a port for electrically connecting to an external device.

17 is a perspective view of a portable terminal 200A according to an embodiment, and FIG. 18 is a configuration diagram of the portable terminal 200A shown in FIG. 17 .

17 and 18 , the portable terminal 200A (hereinafter referred to as "terminal") has a body 850, a wireless communication unit 710, an A/V input unit 720, a sensing unit 740, and input/ It may include an output unit 750 , a memory unit 760 , an interface unit 770 , a control unit 780 , and a power supply unit 790 .

The body 850 shown in FIG. 17 has a bar shape, but is not limited thereto, and a slide type, a folder type, and a swing type in which two or more sub-bodies are coupled to be movable relative to each other. , and may have various structures such as a swivel type.

The body 850 may include a case (casing, housing, cover, etc.) forming an exterior. For example, the body 850 may be divided into a front case 851 and a rear case 852 . Various electronic components of the terminal may be embedded in a space formed between the front case 851 and the rear case 852 .

The wireless communication unit 710 may include one or more modules that enable wireless communication between the terminal 200A and the wireless communication system or between the terminal 200A and the network in which the terminal 200A is located. For example, the wireless communication unit 710 may include a broadcast reception module 711 , a mobile communication module 712 , a wireless Internet module 713 , a short-range communication module 714 , and a location information module 715 . there is.

The A/V (Audio/Video) input unit 720 is for inputting an audio signal or a video signal, and may include a camera 721 , a microphone 722 , and the like.

The camera 721 may include a camera module 200 according to an embodiment.

The sensing unit 740 detects the current state of the terminal 200A, such as the opening/closing state of the terminal 200A, the position of the terminal 200A, the presence or absence of user contact, the orientation of the terminal 200A, acceleration/deceleration of the terminal 200A, etc. It is possible to generate a sensing signal for controlling the operation of the terminal 200A by sensing. For example, when the terminal 200A is in the form of a slide phone, it is possible to sense whether the slide phone is opened or closed. In addition, it is responsible for sensing functions related to whether the power supply unit 790 is supplied with power and whether the interface unit 770 is coupled to an external device.

The input/output unit 750 is for generating input or output related to sight, hearing, or touch. The input/output unit 750 may generate input data for operation control of the terminal 200A, and may also display information processed by the terminal 200A.

The input/output unit 750 may include a keypad unit 730 , a display module 751 , a sound output module 752 , and a touch screen panel 753 . The keypad unit 730 may generate input data in response to a keypad input.

The display module 751 may include a plurality of pixels whose color changes according to an electrical signal. For example, the display module 751 is a liquid crystal display (liquid crystal display), a thin film transistor-liquid crystal display (thin film transistor-liquid crystal display), an organic light-emitting diode (organic light-emitting diode), a flexible display (flexible display), three-dimensional It may include at least one of a display (3D display).

The sound output module 752 outputs audio data received from the wireless communication unit 710 in a call signal reception, a call mode, a recording mode, a voice recognition mode, or a broadcast reception mode, or stored in the memory unit 760 . Audio data can be output.

The touch screen panel 753 may convert a change in capacitance generated due to a user's touch on a specific area of the touch screen into an electrical input signal.

The memory unit 760 may store a program for processing and control of the control unit 780, and stores input/output data (eg, phone book, message, audio, still image, photo, video, etc.) Can be temporarily saved. For example, the memory unit 760 may store an image captured by the camera 721 , for example, a photo or a moving picture.

The interface unit 770 serves as a passage for connecting to an external device connected to the terminal 200A. The interface unit 770 receives data from an external device, receives power and transmits it to each component inside the terminal 200A, or transmits data inside the terminal 200A to an external device. For example, the interface unit 770 may include a wired/wireless headset port, an external charger port, a wired/wireless data port, a memory card port, a port for connecting a device having an identification module, and an audio I/O (Input/O) Output) port, video I/O (Input/Output) port, and may include an earphone port, and the like.

The controller 780 may control the overall operation of the terminal 200A. For example, the controller 780 may perform related control and processing for voice calls, data communications, video calls, and the like.

The controller 780 may include a multimedia module 781 for playing multimedia. The multimedia module 781 may be implemented within the control unit 780 or may be implemented separately from the control unit 780 .

The controller 780 may perform a pattern recognition process capable of recognizing a handwriting input or a drawing input performed on the touch screen as characters and images, respectively.

The power supply unit 790 may receive external power or internal power under the control of the control unit 780 to supply power required for operation of each component.

Features, structures, effects, etc. described in the above embodiments are included in at least one embodiment of the present invention, and are not necessarily limited to only one embodiment. Furthermore, features, structures, effects, etc. illustrated in each embodiment can be combined or modified for other embodiments by a person skilled in the art to which the embodiments belong. Accordingly, the contents related to such combinations and modifications should be interpreted as being included in the scope of the present invention.

Claims (29)

housing;
a bobbin disposed within the housing;
an elastic member coupled to the bobbin and the housing;
a shape memory alloy member coupled to the bobbin and the elastic member; and
A sensing magnet and a position sensor for detecting the movement of the bobbin in the optical axis direction,
The position sensor through the elastic member is a lens driving device for supplying a driving signal to the shape memory alloy member. According to claim 1,
The elastic member is a lens driving device for electrically connecting the position sensor and the shape memory alloy member. According to claim 1,
The elastic member is coupled to an upper portion of the bobbin and an upper portion of the housing. According to claim 1,
The shape memory alloy member,
a first member at least a portion of which supports a first portion of the bobbin; and
A lens driving device including a second member, at least a portion of which supports a second portion of the bobbin According to claim 1,
Each of the first portion and the second portion is a protrusion protruding from an outer surface of the bobbin. 5. The method of claim 4,
The elastic member.
a first elastic member connected to one end of the first member;
a second elastic member connected to the other end of the first member and one end of the second member; and
and a third elastic member connected to the other end of the second member. 7. The method of claim 6,
a circuit board including a first pad electrically connected to the first elastic member, a third pad electrically connected to the second elastic member, and a third pad electrically connected to the third elastic member lens drive. According to claim 1,
The driving signal is a PWM signal. According to claim 1,
a base disposed under the bobbin and the housing;
When a driving signal is not provided to the shape memory alloy member, the bobbin is in contact with the base. 2. The method of claim 1
It includes a circuit board on which the position sensor is disposed,
wherein the elastic member is electrically connected to the circuit board. 11. The method of claim 10,
The sensing magnet is disposed on the bobbin, and the position sensor is disposed on the housing. According to claim 1,
The position sensor is a lens driving device including a Hall sensor and a driver. According to claim 1,
The position sensor includes a temperature sensing element for measuring an ambient temperature of the shape memory alloy member. 14. The method of claim 13,
The position sensor is a lens driving device including a resistance measuring unit for measuring the resistance of the shape memory alloy member. 7. The method of claim 6,
Each of the first to third elastic members includes an outer frame coupled to the upper portion of the housing,
One end of the first member is coupled to the outer frame of the first elastic member, the other end of the first member and one end of the second member are coupled to the outer frame of the second elastic member, the second member The other end of the lens driving device is coupled to the outer frame of the third elastic member. housing;
a bobbin disposed within the housing;
a first elastic member coupled to an upper portion of the bobbin and an upper portion of the housing;
a second elastic member coupled to a lower portion of the bobbin and a lower portion of the housing;
a first shape memory alloy member coupled to the bobbin and the first elastic member;
a second shape memory alloy member coupled to the bobbin and the second elastic member;
A sensing magnet and a position sensor for detecting the movement of the bobbin in the optical axis direction,
The first elastic member electrically connects the position sensor and the first shape memory alloy member, and the second elastic member electrically connects the position sensor and the second shape memory alloy member. 17. The method of claim 16,
A lens driving device in which a first driving signal is supplied to the first shape memory alloy member through the first elastic member. 17. The method of claim 16,
A lens driving device in which a second driving signal is supplied to the second shape memory alloy member through the second elastic member. 17. The method of claim 16,
The first shape memory alloy member comprises:
a first member at least a portion of which supports a first portion of the bobbin; and
and a second member, at least a portion of which supports a second portion of the bobbin. 20. The method of claim 19,
The second shape memory alloy member comprises:
a third member at least a portion of which supports a third portion of the bobbin; and
and a fourth member at least a portion of which supports a fourth portion of the bobbin. 21. The method of claim 20,
Each of the first to fourth portions is a protrusion protruding from an outer surface of the bobbin. 17. The method of claim 16,
a base disposed under the bobbin and the housing;
In the initial position, the bobbin is positioned to be spaced apart from the base in the optical axis direction. 17. The method of claim 16,
The first elastic member,
a first upper elastic member connected to one end of the first member;
a second upper elastic member connected to the other end of the first member and one end of the second member; and
and a third upper elastic member connected to the other end of the second member. 24. The method of claim 23,
The second elastic member,
a first lower elastic member connected to one end of the third member;
a second lower elastic member connected to the other end of the third member and one end of the fourth member; and
and a third lower elastic member connected to the other end of the fourth member. 25. The method of claim 24,
and a circuit board including a plurality of pads electrically connected to the first to third upper elastic members and the first to third lower elastic members. 23. The method of claim 22,
A first section in which the bobbin moves in an upward direction based on the initial position is larger than a second section in which the bobbin moves in a downward direction based on the initial position. 17. The method of claim 16,
The bobbin is moved in the optical axis direction by the first shape-memory alloy and the second shape-memory alloy,
The length of each of the first and second shape memory alloys is converted within 2% of the total length of the shape memory alloy member within the movement section of the bobbin in the optical axis direction. housing;
a bobbin disposed within the housing;
an elastic member coupled to the bobbin and the housing; and
a shape memory alloy member coupled to the bobbin and the elastic member;
The elastic member includes a first elastic member, a second elastic member, and a third elastic member,
The shape memory alloy member,
a first member having one end coupled to the first elastic member, the other end coupled to the second elastic member, and a middle portion supporting the first portion of the bobbin; and
and a second member having one end coupled to the third elastic member, the other end coupled to the second elastic member, and a middle portion supporting the second portion of the bobbin. housing;
a bobbin disposed within the housing;
an elastic member coupled to the bobbin and the housing;
a shape memory alloy member coupled to the bobbin and the elastic member;
a sensing magnet and a position sensor for detecting movement of the bobbin in an optical axis direction; and
A circuit board electrically connected to the position sensor,
The shape memory alloy member is electrically connected to the circuit board through the elastic member.

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