KR102319554B1 - Lens moving unit and camera module including the same - Google Patents

Abstract

The lens driving device according to the embodiment includes a moving unit on which at least one lens is mounted, a first coil facing and interacting with each other to move the moving unit in the optical axis direction of the lens, and a driving magnet in the optical axis direction of the moving unit a position sensor or a driver including a position sensor for detecting the position of It faces the sensor and is spaced apart from or in contact with the first side in a direction parallel to the optical axis direction, and includes a second side having a second polarity opposite to the first side, and the length of the first side in the optical axis direction is the second side may be greater than or equal to the length in the optical axis direction of

Description

Lens moving unit and camera module including the same}

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

In recent years, the development of IT products such as a mobile phone, a smart phone, a tablet PC, and a notebook computer with a built-in digital camera is being actively conducted. Accordingly, a camera module having a digital camera is required to provide various functions such as auto focusing, shutter, shake improvement or zoom function, and the trend is higher in pixels and smaller in size.

Meanwhile, in the case of a conventional camera module, a hall sensor (not shown) and a sensor magnet (not shown) facing each other in a direction perpendicular to the optical axis direction of the lens may be disposed in order to know the focal position of the lens. In this case, the Hall sensor detects the magnetic field of the sensor magnet, and outputs a voltage corresponding thereto. Although the position of the lens in the optical axis direction can be determined through the voltage output from the Hall sensor, the Hall sensor cannot detect it despite the movement of the lens in the optical axis direction, so there is a limit to accurately grasping the position of the lens. have.

The embodiment provides a lens driving device capable of accurately grasping and controlling a position of a lens, and a camera module including the same.

The lens driving device according to the embodiment includes a moving unit on which at least one lens is mounted; a first coil and a driving magnet that face each other and interact with each other so as to move the moving part in the optical axis direction of the lens; a position sensor for detecting the position of the moving part in the optical axis direction or a driver including the position sensor; and a positively polarized magnet disposed to face the position sensor or the driver, wherein the positively polarized magnet faces the position sensor and includes a first side surface having a first polarity; and a second side facing the position sensor and disposed to be spaced apart from or in contact with the first side in a direction parallel to the optical axis direction, and having a second polarity opposite to the first side; A length in the optical axis direction may be greater than or equal to a length in the optical axis direction of the second side surface.

In addition, the first polarity may be an S pole and the second polarity may be an N pole, or the first polarity may be an N pole and the second polarity may be an S pole.

The positively polarized magnet may include first and second sensing magnets spaced apart from each other; and a non-magnetic barrier rib disposed between the first and second sensing magnets.

The first and second sensing magnets may be spaced apart from each other in a direction parallel to the optical axis direction, or may be disposed spaced apart from each other in the magnetization direction.

or the first side is located above the second side. The second side surface of the lens driving device is located on the first side.

In an initial state before moving the lens in the optical axis direction, the intermediate height of the position sensor may be located on a virtual horizontal plane extending from the upper end of the first side surface in the magnetization direction.

At an initial stage before moving the lens in the optical axis direction, a middle height of the position sensor may coincide with a first point of the first side surface in the magnetizing direction.

In the initial stage before moving the lens in the optical axis direction, the intermediate height of the position sensor may coincide with the non-magnetic barrier rib in the magnetizing direction.

At an initial stage before moving the lens in the optical axis direction, a middle height of the position sensor may coincide with a second point higher than the first point in the magnetization direction.

A difference between the second point and the first point may be as follows.

Here, H2 is the height of the second point, H1 is the height of the first point, ΔD is a value obtained by subtracting the lower displacement width from the upper displacement width of the moving part, and D is the displacement width of the moving part do.

At an initial stage before moving the lens in the optical axis direction, a middle height of the position sensor may coincide with the second side surface.

At a position in which the lens is most moved in the optical axis direction, a middle height of the position sensor may coincide with a point below the lower end of the second side surface.

The first point may correspond to an intermediate height of the first side surface.

The first and second side surfaces may correspond to side surfaces of the first and second sensing magnets facing the position sensor, respectively.

The first and second side surfaces may correspond to side surfaces of the first or second sensing magnet facing the position sensor.

The non-magnetic barrier rib may include voids or a non-magnetic material.

The moving part may move in one direction of the optical axis.

The moving unit may move in both directions of the optical axis.

The lens driving device further includes a fixing part for supporting the driving magnet, and the first and second sensing magnets are coupled, contacted, supported, fixed, temporarily fixed, inserted or seated on the moving part, The position sensor may be coupled, contacted, supported, temporarily fixed, inserted or seated in the fixing unit.

Alternatively, the lens driving device further includes a fixing part for supporting the driving magnet, and the first and second sensing magnets are coupled to, contacted, supported, fixed, temporarily fixed, inserted or seated on the fixing part. And, the position sensor may be coupled, contacted, supported, fixed, temporarily fixed, inserted or seated in the moving unit.

The strength of the magnetic field may be coded with 7 bits to 12 bits.

The length of the non-magnetic barrier rib may be 10% or more or 50% or less of a length of the anode magnetizing magnet in a direction parallel to the optical axis direction.

A length of the positively polarized magnet in a direction parallel to the optical axis direction may be 1.5 times or more of a movable width of the moving part.

The intermediate height of the position sensor may be biased toward any one of the first and second side surfaces.

A camera module according to another embodiment includes an image sensor; a circuit board on which the image sensor is mounted; and the lens driving device.

The lens driving device and the camera module including the same according to the embodiment can accurately detect the movement of the lens in the optical axis direction by arranging the position sensor and the bipolar magnet to detect a magnetic field having a linearly changing intensity. have.

1 is a schematic perspective view of a lens driving device according to an embodiment.
FIG. 2 is a schematic exploded perspective view showing an embodiment of the lens driving device illustrated in FIG. 1 .
FIG. 3 is a schematic perspective view of a lens driving device in which a cover can is removed in FIG. 1 according to an embodiment.
4 is a schematic plan perspective view of a housing member according to an embodiment.
5 is a schematic bottom perspective view of a housing member according to an embodiment.
6 is a schematic exploded perspective view of a driving magnet, a housing member, a first circuit board, and a displacement sensor according to an exemplary embodiment.
7 is a plan perspective view of an upper elastic member.
8 is a plan perspective view of the lower elastic member.
9 is a plan perspective view of the bobbin shown in FIG. 2 according to an embodiment.
10 is a bottom perspective view of the bobbin shown in FIG. 2 according to an embodiment.
11 is an exploded perspective view illustrating a bobbin, a first coil, a displacement sensing unit, and a sensing magnet according to an exemplary embodiment.
12 is a schematic bottom perspective view of a bobbin, a first coil, first and second driving magnets, a displacement sensing unit, and a sensing magnet according to an exemplary embodiment.
13 is a schematic cross-sectional view of a lens driving device according to another embodiment.
14A and 14B are cross-sectional views of the anode magnetization magnet shown in FIG. 13 according to an embodiment, respectively.
15 is a graph for explaining the operation of the lens driving device shown in FIG. 13 .
16 shows a state in which the lens driving device shown in FIG. 13 is moved in the optical axis direction.
17 is a graph illustrating displacement of a moving part according to a current supplied to a first coil in the lens driving apparatus according to the embodiment.
18 is a cross-sectional view of a lens driving device according to another embodiment.
19 is a cross-sectional view of a lens driving device according to another embodiment.
20A and 20B are cross-sectional views of the anode magnetization magnet shown in FIG. 19 according to an embodiment, respectively.
21 is a cross-sectional view of a lens driving device according to another embodiment.
22 is a cross-sectional view of a lens driving device according to another embodiment.
23 is a cross-sectional view of a lens driving device according to another embodiment.
24 is a graph illustrating displacement of a moving part according to a current supplied to a first coil in the lens driving apparatus shown in FIGS. 22 and 23 .
25 is a graph showing the strength of a magnetic field sensed by the position sensor according to the movement distance in the optical axis direction of the moving part by opposing aspects of the position sensor and the bipolar magnet.
26A and 26B are graphs illustrating displacements for each intensity of a magnetic field sensed by a position sensor.
27 is a graph for explaining a change in the strength of a magnetic field according to a moving distance of a moving part of a lens driving device of a comparative example.
28 is a graph illustrating a change in a magnetic field sensed by a position sensor according to movement of a moving part in the lens driving apparatus according to the embodiment.

Hereinafter, a preferred embodiment of the present embodiment will be described so that a person skilled in the art can easily implement it with reference to the accompanying drawings. In the accompanying drawings, it may be noted that the reference numbers indicated for the components are used as much as possible when referring to the same components in other drawings. Also, in the description of the present embodiment, if it is determined that a detailed description of a related well-known function or a known configuration may unnecessarily obscure the gist of the present embodiment, the detailed description thereof may be omitted. In addition, certain features presented in the drawings are enlarged, reduced, or simplified for ease of description, and the drawings and components thereof are not necessarily drawn to scale. However, those skilled in the art will readily appreciate these details.

Hereinafter, the embodiment illustrated in FIGS. 1 to 12 will be described using a Cartesian coordinate system (x, y, z), but the embodiment is not limited thereto. That is, it goes without saying that the embodiment can be described using another coordinate system. In each drawing, the x-axis and the y-axis mean a plane perpendicular to the optical axis. For convenience, the z-axis direction, which is the optical axis direction, may be referred to as the first direction, the x-axis direction as the second direction, and the y-axis direction as the third direction. . Also, the first direction may be a vertical direction, and each of the second and third directions may be a horizontal direction.

1 is a schematic perspective view of a lens driving apparatus 100 according to an embodiment, FIG. 2 is a schematic exploded perspective view according to an embodiment of the lens driving apparatus 100 illustrated in FIG. 1 , and FIG. 3 is 1 shows a schematic perspective view of the lens driving device 100 in which the cover can 102 is removed according to an embodiment.

The lens driving device 100 according to the embodiment is a device that adjusts a distance between a lens (not shown) and an image sensor (not shown) in a camera module so that the image sensor is positioned at a focal length of the lens. That is, the lens driving device 100 is a device that performs an auto-focusing function.

1 to 3 , the lens driving device 100 according to the embodiment includes a cover can 102 , a bobbin 110 , a first coil 120 , a driving magnet 130 , and a housing member. 140 , an upper elastic member 150 , a lower elastic member 160 , a first circuit board 170 , a displacement sensing unit 180 , a sensing magnet 182 , and a base 190 . .

The cover can 102 may be in the form of a box as a whole, and may be configured to be mounted, seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed on the upper portion of the base 190 . The cover can 102 is mounted, seated, contacted, fixed, temporarily fixed, supported, combined, or disposed on the base 190 in the receiving space formed by the bobbin 110, the first coil 120, and the driving magnet 130 ), the housing member 140 , the upper elastic member 150 , the lower elastic member 160 , the first circuit board 170 , the displacement detecting unit 180 , and the sensing magnet 182 may be accommodated therein.

The cover can 102 may include an opening 101 on its upper surface through which a lens (not shown) coupled to the bobbin 110 can be exposed to external light. In addition, a window made of a light-transmitting material may be provided in the opening 101 , thereby preventing foreign substances such as dust or moisture from penetrating into the camera module.

The cover can 102 may include a first groove portion 104 formed in a lower portion, and the base 190 may include a second groove portion 192 formed in an upper portion thereof. At this time, as will be described later, when the cover can 102 is mounted, seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed on the base 190, the portion in contact with the first groove 104 (that is, A second groove 192 may be formed in a position corresponding to the first groove 104 . A concave portion having a predetermined area may be formed by contacting, disposing, or combining the first groove portion 104 and the second groove portion 192 . An adhesive member having a viscosity, for example, epoxy may be injected into the groove and applied thereto. That is, the adhesive member applied to the concave portion fills a gap between the facing surfaces of the cover can 102 and the base 190 through the concave portion, so that the cover can 102 is mounted on the base 190 . , can be seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed to seal between the cover can 102 and the base 190, and the cover can 102 is mounted on the base 190, The sides may be closed or coupled while seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed.

In addition, the cover can 102 may further include a third groove portion 106 . Here, the third groove portion 106 is formed on a surface corresponding to the terminal surface of the first circuit board 170 , and prevents the plurality of terminals 171 and the cover can 102 formed on the terminal surface from interfering with each other. The third groove portion 106 may be concavely formed on the entire surface facing the terminal surface of the first circuit board 170 , and an adhesive member is applied to the inside of the third groove portion 106 to cover the can 102 and the cover can 102 . The base 190 and the first circuit board 170 may be sealed or coupled.

The first groove portion 104 and the third groove portion 106 are formed in the cover can 102 , and the second groove portion 192 is formed in the base 190 , but the embodiment is not limited thereto. That is, according to another embodiment, the first to third grooves 104 , 192 , and 106 may be formed only on the base 190 or only on the cover can 102 .

In addition, the material of the above-described cover can 102 may include metal, but the embodiment is not limited to the material of the cover can 102 . In addition, the cover can may be formed of a magnetic material.

The base 190 may be provided in a rectangular shape as a whole, and may include a stepped portion protruding a predetermined thickness outward to surround the lower edge of the base 190 . The stepped portion may be in the form of a continuous band or some intermittent band in the middle. The predetermined thickness of the stepped portion is the same as the side thickness of the cover can 102 , and when the cover can 102 is mounted, seated, contacted, fixed, temporarily fixed, supported, coupled, or disposed on the base 190 , the cover can The side of 102 may be mounted, seated, contacted, coupled, fixed, supported, or disposed on the top or side of the stepped portion. For this reason, the cover can 102 coupled to the upper side of the stepped portion may be guided by the stepped portion, and further, the end of the cover can 102 may be coupled to face the stepped portion. Here, the end of the cover can 102 may include a bottom surface or a side surface. In this case, the stepped portion and the end of the cover can 102 may be adhesively fixed or bonded or sealed by an adhesive or the like.

In the stepped portion, a second groove portion 192 may be formed at a position corresponding to the first groove portion 104 of the cover can 102 . As described above, the second groove portion 192 may be combined with the first groove portion 104 of the cover can 102 to form a groove portion, and may form a space in which the adhesive member is filled.

Like the cover can 102 , the base 190 may include an opening near the center. The opening may be formed at a position corresponding to the position of the image sensor disposed in the camera module.

In addition, the base 190 may include four guide members 194 protruding at right angles to a predetermined height upward from the four corners. The guide member 194 may have a polygonal prism shape. The guide member 194 may be mounted, inserted, seated, contacted, coupled, fixed, supported, or disposed in the lower guide groove 148 of the housing member 140 to be described later. In this way, due to the guide member 194 and the lower guide groove 148, when the housing member 140 is mounted, seated, contacted, coupled, fixed, supported, or disposed on the upper portion of the base 190, the base 190 ), the position of the coupling of the housing member 140 may be guided, and the coupling area may be widened, and the housing member 140 may be coupled due to vibration or the like during the operation of the lens driving device 100 . During the process, it can be prevented from being deviated from the reference position to be mounted due to the operator's mistake.

4 is a schematic plan perspective view of a housing member 140 according to an embodiment, FIG. 5 is a schematic bottom perspective view of the housing member 140 according to an embodiment, and FIG. 6 is a driving unit according to an embodiment. A schematic exploded perspective view of the magnet 130 , the housing member 140 , the first circuit board 170 , and the displacement sensing unit 180 is shown, and FIG. 7 is a plan perspective view of the upper elastic member 150 , FIG. 8 shows a plan perspective view of the lower elastic member 160 .

4 to 6 , the housing member 140 may have an overall hollow column shape (eg, a hollow quadrangular column shape as illustrated). The housing member 140 has a shape to support at least two or more driving magnets 130 and the first circuit board 170 , and the bobbin 110 therein has a first direction z with respect to the housing member 140 . The bobbin 110 may be accommodated to be movable in the axial direction.

The housing member 140 may include four flat sides 141 . The side surface 141 of the housing member 140 may be formed to have an area corresponding to or larger than that of the driving magnet 130 .

As shown in FIG. 6 , a driving magnet 130 is mounted, inserted, seated, contacted, combined, fixed, supported, or A through hole (or groove) 141a for a magnet that may be disposed may be formed. The through-hole 141a for the magnet may have a size and/or a shape corresponding to the driving magnet 130 , and may also have a shape capable of guiding the driving magnet 130 . One of the driving magnets 130 (hereinafter, 'first driving magnet 131') and the other one (hereinafter, 'second driving The magnets 132') may be mounted, inserted, seated, contacted, coupled, fixed, supported, or disposed, respectively. In the case of the embodiment, only two driving magnets 130 are shown, but the embodiment is not limited thereto. That is, of course, four driving magnets 130 may be disposed.

The type of the driving magnet 130 described above can be broadly divided into ferrite, alnico, and rare earth magnets, and can be divided into an inner magnetic type (Ptype) and an outer magnetic type (F-type) according to the shape of the magnetic circuit. can be classified. The embodiment is not limited to the type of the driving magnet 130 .

In addition, a displacement sensing unit 180, which will be described later, is mounted, inserted, seated, contacted, coupled, on one side perpendicular to the first both sides of the four side surfaces 141 of the housing member 140 or on a side other than the first both sides; A through hole 141b or a groove (not shown) for a sensor to be fixed, supported, or disposed may be formed. The sensor through-hole 141b may have a size and shape corresponding to the displacement sensing unit 180 to be described later, and may be formed to be spaced apart from the first and second magnet through-holes 141a and 141a' by a predetermined distance. The sensor through hole 141b may be formed in a side surface on which the first circuit board 170 is mounted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed among the side surfaces 141 of the housing member 140 . have.

In addition, on one side of the housing member 140, at least one mounting protrusion 149 for allowing the first circuit board 170 to be mounted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed. can be provided.

The mounting protrusion 149 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed in the mounting through hole 173 formed in the first circuit board 170 . At this time, the mounting through-hole 173 and the mounting protrusion 149 may be contacted or coupled in a shape fitting method or an interference fitting method, but these 173 and 149 are the first circuit board 170 in the housing. Mounting, seating, contact, coupling, fixing, temporarily fixing, supporting, or disposed on the member 140 may be a simple guide.

Here, the other side opposite to one side among the four side surfaces 141 of the housing member 140 may be configured as a flat plane, but is not limited thereto.

Although not shown, through-holes for the third and fourth magnets may be additionally disposed on the second side surfaces of the housing member 140 that are perpendicular to the first side surfaces.

At this time, the first through-hole 141a for the magnet and the second through-hole 141a' for the magnet have the same size and the same shape, and (almost) the same over the entire lateral length of the first both sides of the housing member 140 It may have a lateral length. On the other hand, the third through-hole for the magnet and the fourth through-hole for the magnet have the same size and the same shape as each other, and have a lateral length than the first through-hole (141a) for the magnet and the through-hole (141a') for the second magnet. can be made small. This is to secure a space for the sensor through-hole 141b since the sensor through-hole 141b must be formed on the second both side surfaces where the third or fourth through-hole for the magnet is formed.

The first driving magnet 131 and the second driving magnet 132 have the same size and shape as each other, and having substantially the same lateral length over the entire lateral length of the first both sides of the housing member 140 is described above. It's like a bar. And, the third and fourth driving magnets (not shown) that can be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed in the through-holes for the third and fourth magnets (not shown), respectively. ) may have the same size and the same shape as each other, and may be formed to have a lateral length smaller than that of the first driving magnet 131 and the second driving magnet 132 .

Here, like the first and second magnet through-holes 141a and 141a ′, the third and fourth magnet through-holes may be symmetrically disposed on a straight line with respect to the center of the housing member 140 . That is, the third and fourth driving magnets (not shown) may be symmetrically disposed on a straight line with respect to the center or the center of the housing member 140 .

If the first and second driving magnets 131 and 132 or the third and fourth driving magnets are disposed to face each other while being biased to one side regardless of the center of the housing member 140, the bobbin 110 Since the electromagnetic force acts on the first coil 120 to be biased to one side, there may be a possibility that the bobbin 110 is tilted. In other words, similarly to the first and second driving magnets 131 and 132 , the third and fourth driving magnets are symmetrically disposed on a straight line with respect to the center of the housing member 140 , so that the bobbin 110 . And by applying an unbiased electromagnetic force to the first coil 120 , it is possible to guide the bobbin 110 to move in the first direction easily and accurately.

Hereinafter, for convenience of description, it is assumed that the lens driving apparatus 100 according to the embodiment has only the first and second driving magnets 131 and 132 , but even when further including the third and fourth driving magnets, the following The description of can be applied.

A plurality of first stoppers 143 may protrude from the upper surface of the housing member 140 . The first stopper 143 is for preventing collision between the cover can 102 and the housing member 140 body, and when an external shock occurs, the upper surface of the housing member 140 is placed on the upper inner surface of the cover can 102 . Direct collisions can be avoided. In addition, the first stopper 143 may also serve to guide the installation position of the upper elastic member 150 . For example, referring to FIGS. 3 and 7 , a guide groove 155 having a shape corresponding to a position corresponding to that of the first stopper 143 may be formed in the upper elastic member 150 .

In addition, a plurality of upper frame support protrusions 144 in which the outer frame 152 of the upper elastic member 150 is inserted, seated, contacted, fixed, temporarily fixed, coupled, supported, or disposed on the upper side of the housing member 140 . may be formed to protrude. A first through hole (or groove) 152a having a corresponding shape may be formed in the outer frame 152 of the upper elastic member 150 corresponding to the upper frame support protrusion 144 . The upper frame support protrusion 144 may be fixed with an adhesive or fusion after being inserted, seated, contacted, fixed, temporarily fixed, combined, supported, or disposed in the first through hole 152a, and the fusion is thermal fusion or ultrasonic fusion. and the like.

In addition, a plurality of lower frame support protrusions 147 to which the outer frame 162 of the lower elastic member 160 is coupled may protrude below the housing member 140 . The lower frame support protrusion 147 may be formed at four lower corners of the housing member 140 , respectively. On the other hand, referring to FIG. 8 , the outer frame 162 of the lower elastic member 160 at a position corresponding to the lower frame support protrusion 147 is mounted, inserted, seated, contacted, coupled to the lower frame support protrusion 147 . , fixed, temporarily fixed, supported, or a fastening portion 162a that may be disposed may be formed, which may be fixed by an adhesive or fusion bonding, and the fusion may include thermal fusion or ultrasonic fusion.

Also, the housing member 140 may be a yoke housing member capable of performing a yoke function. In the structure of the yoke housing member, the structure may be formed to be spaced apart from the inner surface of the upper elastic member 140 and the upper surface of the yoke. This is to prevent the movement of the bobbin 110 in the upward direction and interference with the yoke.

Alternatively, the yoke (not shown) itself may serve as the housing member 140 . In this case, the yoke may be coupled to the base 190 , and the upper elastic member 150 may be disposed under the yoke or inside the yoke.

According to another embodiment, a separate cover may be further disposed on the upper portion of the yoke. In this case, the upper elastic member 150 may be disposed above the yoke or between the yoke and the cover, and the upper elastic member 150 may be coupled to the cover or the yoke.

Meanwhile, the driving magnets 130: 131 and 132 may be fixed to the magnet through-holes 141a and 141a' with an adhesive, but the present invention is not limited thereto, and an adhesive member such as a double-sided tape may be used. Alternatively, as a modified embodiment, a concave-shaped magnet seating part (not shown) may be formed on the inner surface of the housing member 140 instead of the through-holes 141a and 141a ′ for the first and second magnets, unlike shown in the drawings. In addition, the magnet seating portion may have a size and shape corresponding to the size and shape of the driving magnet 130 .

The driving magnet 130 may be installed at a position facing the first coil 120 located on the outer peripheral surface of the bobbin 110 . In addition, the driving magnet 130 may be configured separately as shown, or may be configured as a single body as shown. In an embodiment, the driving magnet 130 may be disposed such that the surface facing the first coil 120 of the bobbin 110 is the N pole and the outer surface is the S pole. However, the present invention is not limited thereto, and the reverse configuration is also possible.

In addition, the driving magnet 130 may be configured to be divided into two planes perpendicular to the optical axis. That is, the driving magnet 130 is a positively polarized magnet, and a first magnet (not shown) and a second magnet (not shown) disposed to face each other with a non-magnetic barrier rib (not shown) interposed therebetween in a plane perpendicular to the optical axis. ) can be composed of Here, the non-magnetic barrier rib may be air or a non-magnetic material. The first and second magnets may be disposed to have opposite polarities, but embodiments are not limited thereto and may have various shapes. The positively polarized magnet will be described later in detail with reference to FIGS. 14A, 14B, 20A, and 20B.

The first and second driving magnets 131 and 132 have a rectangular parallelepiped shape having a predetermined width, and are seated in the first and second through-holes 141a and 141a' for the first and second driving magnets, respectively. A wide surface or a partial surface of the magnets 131 and 132 may form a part of the side surface (outer surface or inner surface) of the housing member 140 . In addition, the first and second driving magnets 131 and 132 may be disposed on or coupled to the inner surface of the above-described yoke while being disposed on the side surface of the housing member 140 , and the inner surface of the yoke without the housing member 140 . It may be coupled or fixed to the side. In this case, the driving magnets 131 and 132 facing each other may be installed parallel to each other. In addition, the opposite surfaces of the driving magnet 130 and the first coil 120 of the bobbin 110 may be flatly disposed to be parallel to each other. However, the present invention is not limited thereto, and either one of the driving magnet 130 and the second coil 120 of the bobbin 110 may be flat, and the other may be configured as a curved surface. Alternatively, both the first coil 120 of the bobbin 110 and the opposite surface of the driving magnet 130 may be curved surfaces, and in this case, the first coil 120 of the bobbin 110 and the driving magnet 130 may be curved. ) may be formed to have the same curvature of opposite surfaces.

In addition, as described above, one side of the housing member 140 is provided with a through-hole 141b or a groove for the sensor, and the displacement sensing unit 180 is mounted, inserted, and installed in the through-hole 141b or groove for the sensor. Seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed, and the displacement sensing unit 180 may be electrically coupled to one surface of the first circuit board 170 by soldering or soldering. In other words, the first circuit board 170 is mounted, inserted, seated, contacted, coupled to the outer surface of one side provided with the sensor through hole 141b or groove among the four side surfaces 141 of the housing member 140 . , fixed, temporarily fixed, supported, or disposed.

The displacement detecting unit 180 may sense/determine a first displacement value of the bobbin 110 in the first direction together with the sensing magnet 182 . To this end, the displacement sensing unit 180 and the sensor through hole 141b or groove may be disposed at a position corresponding to the position of the sensing magnet 182 . As shown, the sensing magnet 182 may be implemented as a bipolar magnetized magnet divided into two upper and lower in order to increase the strength of the magnetic field, but the embodiment is not limited thereto.

The displacement detecting unit 180 may be a sensor detecting a change in magnetic force emitted from the sensing magnet 182 of the bobbin 110 . For example, the displacement sensor 180 may be a Hall sensor, but the embodiment is not limited thereto. According to another embodiment, any sensor capable of detecting a change in magnetic force other than a Hall sensor may be used as the displacement detecting unit 180, and any sensor capable of detecting a position other than magnetic force is possible, yes For example, a method using a photoreflector or the like is also possible. When the displacement sensing unit 180 is implemented as a Hall sensor, calibration for the actuator driving distance may be additionally performed based on the Hall voltage difference with respect to the change in the magnet flux (ie, magnetic flux density) detected by the Hall sensor. . For example, when the displacement sensor 180 is implemented as a Hall sensor, the Hall sensor 180 may have a plurality of pins. For example, the plurality of pins may include first and second pins. The first pin may include pins 1-1 and 1-2 respectively connected to voltage and ground, and the second pin may include pins 2-1 and 2-2 for outputting a sensed result. can Here, the sensed result output through the 2-1 and 2-2 pins may be in the form of a current, but the embodiment is not limited to the form of a signal. The first circuit board 170 is connected to the Hall sensor 180 to supply power to the 1-1 and 1-2 pins and to receive signals from the 2-1 and 2-2 pins.

The first circuit board 170 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on one side of the housing member 140 . In this case, the installation position of the first circuit board 170 may be guided by the mounting protrusion 149 formed on one side of the housing member 140 as described above. One or a plurality of mounting protrusions 149 may be formed, and when two or more are formed, it may be easier to guide the arrangement position of the first circuit board 170 .

In addition, the first circuit board 170 is provided with a plurality of terminals 171 , and may supply current required by the first coil 120 and the displacement sensor 180 of the bobbin 110 by receiving external power. . The number of terminals 171 formed on the first circuit board 170 may be increased or decreased according to the types of components that need to be controlled. For example, the plurality of terminals 171 of the first circuit board 170 may include a power terminal receiving external power and an I ² C communication terminal. Here, one of the power terminals may be a terminal connected to the supply voltage, and the other of the power terminals may be a terminal connected to the ground.

Also, referring to FIGS. 3 and 6 , at least one pin 172 may be provided on the first circuit board 170 . As shown, there may be four pins 172, but the number of pins 172 may be more or less than four. For example, the four pins 172 may be a test pin, a hole pin, a VCM+ pin, and a VCM- pin, but the embodiment is not limited to the type of these pins. Here, the test pin may be a pin used to evaluate the performance of the lens driving device 100 . The hole pin may be a pin used to extract data output from the displacement sensing unit 180 . The VCM+ pin and the VCM- pin may be pins used to evaluate the performance of the lens driving device 100 in a state in which feedback from the displacement sensor 180 is not received.

According to an embodiment, the first circuit board 170 may be provided as an FPCB. The first circuit board 170 may include a controller (not shown) that readjusts the amount of current applied to the first coil 120 based on the first displacement value sensed by the displacement sensor 180 . For example, the controller may receive signals from pins 2-1 and 2-2 of the Hall sensor 180 . The controller may be mounted on the first circuit board 170 . Alternatively, according to another embodiment, the control unit may not be mounted on the first circuit board 170 but may be mounted on a separate board. Here, the other separate board may be a second circuit board (not shown) on which an image sensor (not shown) is mounted in the camera module, or may be a separate board.

In the above-described example, the lens driving apparatus 100 has been described as including the displacement detection unit 180, but in some cases, the displacement detection unit 180 may be omitted.

In addition, in the above example, the first circuit board 170 has been described as being mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the outer surface of the housing member 140 , but in the embodiment is not limited thereto. That is, according to another exemplary embodiment, when the lens driving device 100 does not include the displacement detecting unit 180 , the first circuit board 170 is formed of the housing member 140 instead of the outer surface of the housing member 140 . It may be located below.

9 is a plan perspective view showing the bobbin 110 shown in FIG. 2 according to an embodiment, and FIG. 10 is a bottom perspective view showing the bobbin 110 shown in FIG. 2 according to an embodiment.

4 and 5, 7 and 8, and 9 and 10, the upper elastic member 150 and the lower elastic member 160 are upward and/or descending in the optical axis direction of the bobbin 110. It can be supported flexibly. The upper elastic member 150 and the lower elastic member 160 may be provided as a leaf spring, but the embodiment is not limited to the shape of each of the upper and lower elastic members 150 and 160 .

The upper elastic member 150 includes an inner frame 151 coupled to the bobbin 110 , an outer frame 152 coupled to the housing member 140 , and a connector connecting the inner frame 151 and the outer frame 152 . (153) may be included.

In addition, the lower elastic member 160 connects the inner frame 161 coupled to the bobbin 110 and the outer frame 162 coupled to the housing member 140 , and the inner frame 161 and the outer frame 162 . It may include a connection part 163 to

The connecting portions 153 and 163 may be bent at least once to form a pattern having a predetermined shape. The bobbin 110 may be elastically (or elastically) supported by the ascending and/or descending operation in the first direction, which is the optical axis direction, through a change in the position of the connection parts 153 and 163 and micro-deformation.

According to an embodiment, as shown in FIG. 7 , the upper elastic member 150 includes a plurality of first through-holes 152a in the outer frame 152 , and a plurality of second through-holes in the inner frame 151 . (151a) may be included.

The first through hole 152a is coupled to the upper frame support protrusion 144 formed on the upper surface of the housing member 140 , and the second through hole 151a is the upper support protrusion 113 formed on the upper surface of the bobbin 110 . can be combined with The upper support protrusion 113 will be described in detail later. That is, the outer frame 152 is mounted, seated, contacted, fixed, temporarily fixed, supported, disposed, or coupled to the housing member 140 through the first through hole 152a, and the inner frame 151 has the second through hole. It may be mounted, seated, contacted, fixed, temporarily fixed, supported, disposed, or coupled to the bobbin 110 through (151a).

The connection part 153 of the upper elastic member 150 connects the inner frame 151 and the outer frame 152 so that the inner frame 151 is elastically deformable within a predetermined range with respect to the outer frame 152 in the first direction. can

At least one of the inner frame 151 and the outer frame 152 of the upper elastic member 150 has a terminal part electrically connected to at least one of the first coil 120 of the bobbin 110 or the first circuit board 170 . It may include at least one or more.

Referring to FIG. 8 , the lower elastic member 160 includes a plurality of fastening portions 162a in the outer frame 162 , and a plurality of third through holes (or grooves) 161a in the inner frame 161 . may include

As described above, the fastening portion 162a may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the lower surface of the housing member 140, and the third through hole 161a is The lower support protrusion 114 formed on the lower surface of the bobbin 110 shown in FIG. 10 may be in contact, coupled, fixed, or temporarily fixed. That is, the outer frame 162 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the housing member 140 through the fastening portion 162a, and the inner frame 161 is It may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the bobbin 110 through the third through hole 161a.

The connection part 163 of the lower elastic member 160 connects the inner frame 161 and the outer frame 162 so that the inner frame 161 is elastically deformable within a predetermined range with respect to the outer frame 162 in the first direction. can

The lower elastic member 160 may include a first lower elastic member 160a and a second lower elastic member 160b separated from each other. Through this two-division structure, the first lower elastic member 160a and the second lower elastic member 160b of the lower elastic member 160 may receive different polarities of power or different currents. That is, after the inner frame 161 and the outer frame 162 are coupled to the bobbin 110 and the housing member 140 , respectively, the inner frame corresponding to both ends of the first coil 120 disposed on the bobbin 110 . By providing a solder portion at a position of the frame 161, a conductive connection such as soldering may be performed in the solder portion to receive power of different polarities or different currents. In addition, the first lower elastic member 160a is electrically connected to one of both ends of the first coil 120 , and the other one of the both ends of the first coil 120 and the second lower elastic member 160b are connected to each other. It may be electrically connected to receive current and/or voltage from the outside. To this end, at least one of the inner frame 161 and the outer frame 162 of the lower elastic member 160 is electrically connected to at least one of the first coil 120 or the first circuit board 170 of the bobbin 110 . It may include at least one terminal unit connected to the Both ends of the first coil 120 may be disposed opposite to each other with respect to the bobbin 110 , or may be disposed adjacent to the same side.

Meanwhile, the upper elastic member 150 and the lower elastic member 160 , the bobbin 110 and the housing member 140 may be assembled through thermal fusion and/or bonding using an adhesive or the like. At this time, according to the assembly sequence, the fixing operation can be finished by bonding using an adhesive after fixing by thermal fusion.

As another embodiment, the upper elastic member 150 may be configured in a two-part structure as illustrated in FIG. 8 , and the lower elastic member 160 may be configured in an integrated structure as illustrated in FIG. 7 .

11 is an exploded perspective view of the bobbin 110, the first coil 120, the displacement sensing unit 180, and the sensing magnet 182 according to an embodiment, and FIG. 12 is the bobbin 110 according to an embodiment. ), the first coil 120 , the first and second driving magnets 131 and 132 , the displacement sensing unit 180 , and a schematic bottom perspective view of the sensing magnet 182 .

The bobbin 110 may be installed in the inner space of the housing member 140 to be reciprocally movable in the optical axis direction. The first coil 120 is installed on the outer peripheral surface of the bobbin 110 to electromagnetically interact with the driving magnet 130 of the housing member 140 to reciprocate the bobbin 110 in the first direction.

In addition, the bobbin 110 is elastically (or elastically) by the upper elastic member 150 and the lower elastic member 160 so that the bobbin 110 moves in the first direction, which is the optical axis direction, to perform the auto-focusing function. ) can be supported.

Although not shown in the bobbin 110, at least one lens may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed therein. For example, the bobbin 110 may include an installed lens barrel (not shown). The lens barrel is a component of a camera module to be described later and may not be an essential component of the lens driving device. The lens barrel may be coupled to the inside of the bobbin 110 in various ways. For example, a female thread may be formed on the inner peripheral surface of the bobbin 110 , and a male thread corresponding to the thread may be formed on the outer peripheral surface of the lens barrel, and the lens barrel may be coupled to the bobbin 110 by screwing these threads. However, this is not limited thereto, and the lens barrel may be directly fixed to the inside of the bobbin 110 by a method other than screwing, without forming a screw thread on the inner circumferential surface of the bobbin 110 .

Alternatively, one or more lenses may be integrally formed with the bobbin 110 without a lens barrel. The lens coupled to the lens barrel may be configured as one sheet, or two or more lenses may be configured to form an optical system.

In addition, a plurality of upper support protrusions 113 and a plurality of lower support protrusions 114 may respectively protrude from the upper and lower surfaces of the bobbin 110 . The upper support protrusion 113 may be provided in a cylindrical or prismatic shape, as shown in FIG. 9 , and couple, fix, and temporarily fix the inner frame 151 and the bobbin 110 of the upper elastic member 150 . , contact, or support. According to an embodiment, the second through hole 151a may be formed at a position corresponding to the upper support protrusion 113 of the inner frame 151 of the upper elastic member 150 . In this case, the upper support protrusion 113 and the second through hole 151a may be fixed by thermal fusion, or may be fixed with an adhesive member such as epoxy. In addition, a plurality of upper support protrusions 113 may be provided. In this case, the distance between each of the upper support protrusions 113 may be appropriately arranged within a range that can avoid interference with surrounding components. That is, each of the upper support protrusions 113 may be arranged at regular intervals symmetrically with respect to the center of the bobbin 110 , and their intervals are not constant, but on a specific virtual line passing through the center of the bobbin 110 . It may be formed to be symmetrical with respect to

As shown in FIG. 10 , the lower support protrusion 114 may be provided in a cylindrical or prismatic shape like the upper support protrusion 113 , and the inner frame 161 and the bobbin 110 of the lower elastic member 160 . may be coupled, fixed, temporarily fixed, contacted, or supported. According to an embodiment, a third through hole 161a may be formed at a position corresponding to the lower support protrusion 114 of the inner frame 161 of the lower elastic member 160 . In this case, the lower support protrusion 114 and the third through hole 161a may be fixed by thermal fusion, or may be fixed with an adhesive member such as epoxy. In addition, a plurality of lower support protrusions 114 as shown in FIG. 10 may be provided. In this case, the distance between each of the lower support protrusions 114 may be appropriately arranged within a range that can avoid interference with surrounding components. That is, each of the lower support protrusions 114 may be arranged at regular intervals symmetrically with respect to the center of the bobbin 110 .

In addition, on the upper and lower surfaces of the bobbin 110 , the upper escape groove 112 and the lower side are located at positions corresponding to the connection part 153 of the upper elastic member 150 and the connection part 163 of the lower elastic member 160 . Evacuation grooves 118 may be formed, respectively.

Since the upper escape groove 112 and the lower escape groove 118 are provided, spatial interference between the connection parts 153 and 163 and the bobbin 110 when the bobbin 110 moves in the first direction with respect to the housing member 140 This can be removed to make it easier to elastically deform the connection parts 153 and 163 . In addition, the location of the upper escape groove 112 may be disposed at the corner of the housing member 140 as illustrated in FIG. 9 , but may be disposed on the side according to the shape and/or position of the connection part of the elastic member.

In addition, on the outer peripheral surface of the bobbin 110, a seating groove 116 for a coil in which the first coil 120 is mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed may be provided, Examples are not limited thereto. That is, according to another embodiment, the first coil 120 is directly mounted on the outer circumferential surface of the bobbin 110, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or instead of being disposed, the bobbin 110 A coil ring (not shown) having the same shape as the outer circumferential shape of the bobbin 110 is mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed adjacent to the outer circumferential surface of the bobbin 110, the first coil 120 ) may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the coil ring.

The first coil 120 is to be provided as a ring-shaped coil block mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the outer peripheral surface of the bobbin 110 or the seating groove 116 for the coil. However, the present invention is not limited thereto, and the first coil 120 may be directly wound on the outer circumferential surface of the bobbin 110 or the coil seating groove 116 . When the pre-wound first coil 120 is mounted, inserted, or disposed, it may be mounted, inserted, or disposed from the upper or lower portion of the bobbin 110 .

According to an embodiment, the first coil 120 may be formed in an approximately octagonal shape as shown in FIG. 11 . This is a shape corresponding to the shape of the outer peripheral surface of the bobbin 110, and the bobbin 110 may also have an octagonal shape. In addition, at least four surfaces of the first coil 120 may be provided in a straight line, and a corner portion connecting these surfaces may be implemented as a round or a straight line. In this case, the portion formed in a straight line may be a surface corresponding to the driving magnet 130 . Also, a surface of the driving magnet 130 corresponding to the first coil 120 may have the same curvature as that of the first coil 120 . That is, if the first coil 120 is a straight line, the corresponding driving magnet 130 may have a straight line. If the first coil 120 is curved, the corresponding driving magnet 130 may have a curved surface. , and may also have the same curvature. In addition, even if the first coil 120 is curved, the corresponding driving magnet 130 may have a straight surface, or vice versa.

The first coil 120 is for performing an autofocus function by moving the bobbin 110 in the optical axis direction. When a current is supplied, it can electromagnetically interact with the driving magnet 130 to form an electromagnetic force. As described above, the electromagnetic force may move the bobbin 110 .

On the other hand, the first coil 120 may be configured to correspond to the driving magnet 130 . As shown, the driving magnet 130 is configured as a single body so that the entire surface facing the first coil 120 . When is provided to have the same polarity, the surface corresponding to the first coil 120 and the driving magnet 130 may also be configured to have the same polarity. On the other hand, although not shown, if the driving magnet 130 is divided into two planes perpendicular to the optical axis so that the surface facing the first coil 120 is divided into two or more, the first coil 120 It is also possible to be divided into a number corresponding to the divided driving magnet 130 .

Meanwhile, the lens driving device 100 may further include a sensing magnet 182 . The sensing magnet 182 may be mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported, or disposed on the bobbin 110 . For this reason, the sensing magnet 182 may move in the first direction by the same amount of displacement as the bobbin 110 when the bobbin 110 moves in the first direction. In addition, the sensing magnet 182 may be integrally configured with the bobbin 110 , and may be disposed such that an upper direction of the bobbin 110 is an N pole and a lower direction of the bobbin 110 is an S pole. However, the present invention is not limited thereto, and the reverse configuration is also possible.

In addition, the sensing magnet 182 may be implemented as a bipolar magnetizing magnet divided into two in a plane perpendicular to the optical axis. The positively polarized magnet will be described later in detail with reference to FIGS. 14A and 14B and FIGS. 20A and 20B .

9 to 12 , the bobbin 110 may further include a receiving groove 117 for accommodating the sensing magnet 182 on the outer peripheral surface of the bobbin 110 .

The receiving groove 117 may be formed in an inner direction of the bobbin 110 to a predetermined depth from the outer surface of the bobbin 110 . Specifically, the receiving groove 117 may be formed on one side of the bobbin 110 so that at least a portion of the receiving groove 117 is located inside the first coil 120 .

In addition, at least a portion of the receiving groove 117 may be concave to a predetermined depth in the inner direction of the bobbin 110 more than the coil seating groove 116 . In this way, by forming the accommodating groove 117 in the inner direction of the bobbin 110, the sensing magnet 182 can be accommodated in the bobbin 110, whereby a separate sensing magnet 182 for the sensing magnet 182 can be accommodated. Since there is no need to secure an installation space, the space efficiency of the bobbin 110 can be improved.

In particular, the receiving groove 117 may be disposed at a position corresponding to the position of the displacement sensing unit 180 of the housing member 140 (or a position facing the position sensing sensor 180 ). For this reason, the displacement detecting unit 180 and the sensing magnet 182 may be aligned on the same axis.

The distance d between the sensing magnet 182 and the displacement detection unit 180 can be minimized as the thickness of the first coil 120 and the separation distance between the first coil 120 and the displacement detection unit 180 . Therefore, the magnetic force detection accuracy of the displacement sensor 180 can be improved.

More specifically, as illustrated in FIGS. 9 to 12 , the receiving groove 117 has an inner surface on which one surface of the sensing magnet 182 is supported, and a predetermined depth more inside than the inner surface so that an adhesive can be injected. It may include an adhesive groove 117b concave with the .

The inner surface is one surface positioned in the inner direction toward the center of the bobbin 110, and when the sensing magnet 182 has a rectangular parallelepiped shape, the wide surface of the sensing magnet 182 is contacted or seated.

The bonding groove 117b may be a groove formed so that a portion of the inner surface is concave deeper in the inner direction toward the center of the bobbin 110 . The adhesive groove 117b may be formed up to the inner surface of the bobbin 110 on which one surface of the sensing magnet 182 is mounted, inserted, seated, contacted, coupled, fixed, temporarily fixed, supported or disposed.

As another embodiment, the receiving groove 117 has an outer peripheral surface (ie, a coil seating groove 116 ) on which the second coil 120 is provided from an inner surface on which one surface (ie, a wide surface) of the sensing magnet 182 is supported. ) surface) may be less than or equal to the thickness of the sensing magnet 182 . For this reason, the sensing magnet 182 may be fixed in the receiving groove 117 by the inner pressing force of the first coil 120 due to the winding of the first coil 120 . In this case, it may not be necessary to use an adhesive.

As a further embodiment, although not shown in the drawings, the bobbin 110 is positioned symmetrically with the receiving groove 117 with respect to the center of the bobbin 110 on the outer circumferential surface facing the outer circumferential surface where the receiving groove 117 is formed. 110) may include an additional receiving groove formed on the outer peripheral surface. A weight balancing member may be accommodated in the additional receiving groove. Any one of the coil seating groove 116, the receiving groove 117, and the additional receiving groove may be referred to as a 'first groove', the other may be referred to as a 'second groove', and the other one may be referred to as a 'third groove'. .

According to an embodiment, the sensing magnet 182 may be omitted. In this case, the driving magnet 130 may be used instead of the sensing magnet 182 .

As described above, using the result detected by the displacement detecting unit 180, the embodiment feeds back the amount of displacement in the optical axis direction of the lens to readjust the position of the lens in the optical axis direction, thereby reducing the focus alignment time of the lens. can

In addition, in the embodiment, a sensing magnet 182 provided on the bobbin 110 as a moving unit (or moving body) and a displacement sensing unit 180 provided on a housing member 140 as a fixed unit (or fixed body). The distance between them can be minimized, and thus the amount of displacement in the optical axis direction of the lens can be detected more accurately, so that the lens can be more accurately positioned at the focal length of the lens.

In addition, in the embodiment, the sensing magnet 182 is mounted, seated, contacted, fixed, temporarily fixed, coupled, supported, or disposed inside the bobbin 110 , and the displacement sensing unit 180 is installed inside the housing member 140 . By mounting, seating, contacting, fixing, temporarily fixing, combining, supporting, or disposing on the camera module, space efficiency of the camera module (particularly, bobbin) is improved because a separate space for mounting the displacement sensing unit 180 is not required. can do it

Hereinafter, the configuration and operation of the lens driving apparatus 200A to 200F according to another embodiment will be described with reference to the accompanying drawings.

13 is a schematic cross-sectional view of a lens driving device 200A according to another embodiment.

The lens driving device 200A shown in FIG. 13 includes a fixing part 210, a moving part 220, lower and upper springs 230 and 240, a positive magnetizing magnet (or a two-pole magnetizing magnet) 250 and a position. The sensor 260 (or a driver including a position detection or a position detection sensor) may be included.

The fixing part 210 may include a lower part 212 , a side part 214 , and an upper part 216 . When the moving unit 220 of the lens driving device 200A moves in one direction of the optical axis, the lower portion 212 of the fixing unit 210 may support the moving unit 220 in an initial stationary state, or The moving unit 220 may be supported in an initial stationary state while being spaced apart from the lower portion 212 of the fixed unit 210 by a predetermined distance by the upper and/or lower springs 240 and 230 .

In addition, the side 214 of the fixing portion 210 may serve to support the lower spring 230 and the upper spring 240 , but the lower portion 212 and/or the upper portion 216 of the fixing portion 210 . may support the lower and/or upper springs 230 and 240 . For example, the fixing unit 210 may correspond to the housing 140 supporting the driving magnet 130 in the above-described lens driving device 100 , may correspond to a yoke, and may correspond to the cover can 102 . It may correspond to or may correspond to the base 190 .

The moving unit 220 may be equipped with at least one lens (not shown). For example, the moving unit 220 may correspond to the bobbin 110 in the lens driving apparatus 100 described above, but the embodiment is not limited thereto.

Although not shown, the lens driving device 200A may further include a first coil and a driving magnet. The first coil and the driving magnet included in the lens driving device 200A are disposed to face each other so as to move the moving unit 220 in the z-axis direction, which is the optical axis direction of the lens, and interact.

For example, the first coil and the driving magnet may respectively correspond to the first coil 120 and the driving magnet 130 of the lens driving apparatus 100 described above, but the embodiment is not limited thereto.

In the case of FIG. 13 , the moving unit 220 is illustrated as being movable in one direction (ie, the +z axis direction) of the optical axis, but as will be described later, the moving unit 220 according to another embodiment is the amount of the optical axis. It can move in both directions (ie, the +z-axis direction or the -z-axis direction).

Meanwhile, the position sensor 260 may detect a first displacement value in the z-axis direction, which is the optical axis direction of the moving unit 220 . The position sensor 260 may sense the magnetic field of the bipolar magnet 250 and output a voltage having a level proportional to the strength of the sensed magnetic field.

In order for the position sensor 260 to detect a magnetic field of linearly varying intensity, the anode magnetizing magnet 250 may be disposed to face the position sensor 260 in the y-axis direction, which is the magnetization direction perpendicular to the optical axis direction. .

For example, the position sensor 260 corresponds to the displacement detection unit 180 of the above-described lens driving device 100 , and the positively-polarized magnet 250 is a sensing magnet 182 of the above-described lens driving device 100 . ), but the embodiment is not limited thereto. The types of the anode magnetizing magnet 250 can be broadly divided into ferrite, alnico, and rare earth magnets, and can be classified into an inner magnetic type (Ptype) and an outer magnetic type (F-type) according to the shape of the magnetic circuit. can The embodiment is not limited to the type of the positively-polarized magnet 250 .

According to an embodiment, the positively-polarized magnet 250 may include a side surface facing the position sensor 260 . Here, the side surface may include a first side surface 252 and a second side surface 254 . The first side surface 252 may be a surface having a first polarity, and the second side surface 254 may be a surface having a second polarity opposite to the first polarity. The second side surface 254 may be spaced apart from or in contact with the first side surface 252 in the z-axis direction, which is parallel to the optical axis direction. At this time, the first length L1 of the first side surface 252 in the optical axis direction is equal to or greater than the second length L2 of the second side surface 254 in the optical axis direction, or the second length of the second side surface 254 in the optical axis direction. It can be greater than (L2). Also, in the bipolar magnet 250 , the first magnetic flux density of the first side surface 252 having the first polarity may be greater than the second magnetic flux density of the second side surface 254 having the second polarity.

The first polarity may be the S pole and the second polarity may be the N pole, and conversely, the first polarity may be the N pole and the second polarity may be the S pole.

14A and 14B are cross-sectional views, respectively, of embodiments 250A and 250B of the anode magnetizing magnet 250 shown in FIG. 13 .

Referring to FIG. 14A , the positively polarized magnet 250A may include first and second sensing magnets 250A-1 and 250A-2, and may further include a non-magnetic partition wall 250A-3. can Referring to FIG. 14B , the positively polarized magnet 250B may include first and second sensing magnets 250B-1 and 250B-2, and may further include a non-magnetic partition wall 250B-3. have.

The first and second sensing magnets 250A-1 and 250A-2 shown in FIG. 14A may be spaced apart from each other or disposed in contact with each other, and the first and second sensing magnets 250B-1 shown in FIG. 14B may be disposed in contact with each other. 250B-2) may also be disposed to be spaced apart from or in contact with each other.

According to an embodiment, as shown in FIG. 14A , the first and second sensing magnets 250A-1 and 250A-2 are spaced apart from each other or disposed in contact with each other in a direction parallel to the optical axis direction (ie, the z-axis direction). may be

Alternatively, according to another embodiment, as shown in FIG. 14B , the first and second sensing magnets 250B-1 and 250B-2 may be spaced apart or disposed in contact with each other in the magnetization direction (ie, the y-axis direction). have.

Although the anodic magnetizing magnet 250 shown in FIG. 13 is shown to be a magnet having the structure shown in FIG. 14A , it may be replaced with a magnet having the structure shown in FIG. 14B .

In addition, the non-magnetic barrier rib 250A-3 shown in FIG. 14A may be disposed between the first and second sensing magnets 250A-1 and 250A-2, and the non-magnetic barrier rib 250B shown in FIG. 14B . -3) may be disposed between the first and second sensing magnets 250B-1 and 250B-2. The non-magnetic partition walls 250A-3 and 250B-3 are portions that are substantially non-magnetic and may include a section having little polarity, and may be filled with air or include a non-magnetic material.

In addition, the third length L3 of the non-magnetic barrier ribs 250A-3 and 250B-3 is 5% or more or 50 of the total length LT in a direction parallel to the optical axis direction of the anode magnetizing magnets 250A and 250B. % or less.

15 is a graph for explaining the operation of the lens driving device 200A shown in FIG. 13, wherein the horizontal axis represents the distance moved by the moving unit 220 in the optical axis direction or the z-axis direction parallel to the optical axis direction. Also, the vertical axis may indicate a magnetic field sensed by the position sensor 260 or an output voltage output from the position sensor 260 . The position sensor 260 may output a voltage having a level proportional to the strength of the magnetic field.

13 , in the initial state before moving the lens in the optical axis direction, that is, in the initial state in which the moving unit 220 mounting the lens is fixed without moving, the intermediate height of the position sensor 260 is (z = zh) is located on the virtual horizontal plane HS1 extending in the y-axis direction, which is the magnetization direction, from the upper end 251 of the first side surface 252, or located at a point higher than the virtual horizontal plane HS1. can In this case, referring to FIG. 15 , the strength of the magnetic field detectable by the position sensor 260 may be a value BO that is close to '0' but not '0'. In this initial state, the moving part 220 that mounts the lens and is movable only in the unidirectional +z-axis direction is located at the lowest position.

16 shows a state in which the lens driving device 200A shown in FIG. 13 is moved in the optical axis direction.

17 is a graph showing the displacement of the moving unit 220 according to the current supplied to the first coil in the lens driving apparatus according to the embodiment, wherein the horizontal axis indicates the current supplied to the first coil and the vertical axis indicates the displacement.

Referring to the above-mentioned drawings, as the intensity of the current supplied to the first coil is increased, the moving unit 220 can move up and down to a distance (z=z1) in the +z-axis direction as shown in FIG. 16 . have. In this case, referring to FIG. 15 , the strength of the magnetic field that can be sensed by the position sensor 260 may be B1.

Thereafter, when the intensity of the current provided to the first coil is reduced or the supply of current to the first coil is cut off, the moving unit 220 may descend to an initial position as shown in FIG. 13 . In order for the moving unit 220 to move up and down from the position shown in FIG. 13 to the position shown in FIG. 16 , the electric force of the moving unit 220 is the spring force of the lower and upper springs 230 and 240 (mechanical). force) may be greater.

In addition, in order to restore the moving unit 220 to the original initial position shown in FIG. 13 from the point at which the moving unit 220 is lifted to the highest height as shown in FIG. 16 , the electric force is equal to the spring force of the lower and upper springs 230 and 240 and must be equal to or less than That is, after the moving unit 220 moves up and down in the +z-axis direction, it may return to its original position by the restoring force of the lower and upper springs 230 and 240 .

Here, the lower spring 230 may include first and second lower springs 232 and 234 , and the upper spring 240 may include first and second upper springs 242 and 244 . Here, the lower spring 230 is shown as being separated into two into the first and second lower springs 232 and 234, but the embodiment is not limited thereto. That is, the first and second lower springs 232 and 234 may be integrally formed. Similarly, the upper spring 240 is illustrated as being divided into two first and second upper springs 242 and 244 , but the embodiment is not limited thereto. That is, the first and second upper springs 242 and 244 may be integrally formed.

For example, the lower spring 230 and the upper spring 240 may correspond to the lower and upper elastic members 160 and 150 of the above-described lens driving device 100 , respectively, but the embodiment is not limited thereto.

As illustrated in FIGS. 13 and 16 , when the intermediate height (z=zh) of the position sensor 260 is biased toward either one of the first and second sides 252 and 254 , the position sensor 260 is The sensed magnetic field has only one of the first and second polarities. Accordingly, when the intensity of the magnetic field of the first or second polarity is linearly changed, the position sensor 260 may detect the magnetic field having the first or second polarity that is linearly changed. Referring to FIG. 15 , while the first moving unit 220 moves from the lowest point as shown in FIG. 13 to the highest position as shown in FIG. 16 , the magnetic field sensed by the position sensor 260 is It can be seen that the intensity change is linear.

15 and 17 , it can be seen that the maximum displacement D1 that the moving part 220 of the lens driving apparatus 200A shown in FIG. 13 can move is z1.

18 is a cross-sectional view of a lens driving device 200B according to another embodiment.

Unlike the lens driving device 200A shown in FIG. 13 , in the case of the lens driving device 200B shown in FIG. 18 , in the initial state before moving the lens in the optical axis direction, the intermediate height of the position sensor 260 ( The first point of the first side surface 252 may be viewed in the y-axis direction where z=zh) is the magnetization direction. Here, the first point may be any point between the upper end 251 and the lower end of the first side surface 252 , for example, an intermediate height of the first side surface 252 .

In the state before the moving part 220 moves, the positively-polarized magnet 250 of the lens driving device 200B shown in FIG. 18 is higher than the positively-polarized magnet 250 of the lens driving device 200A shown in FIG. 13 . A predetermined distance (z2-zh) may be higher. In this case, referring to FIG. 15 , the lowest value of the magnetic field having the first polarity sensed by the position sensor 260 may be B2 greater than B0.

As a current is applied to the first coil in the lens driving device shown in FIG. 18 , the moving unit 220 may move up and down to a maximum height z1 like the lens driving device 200A shown in FIG. 16 . In this case, the maximum lifting height of the moving unit 220 may be changed by adjusting the elastic modulus of the lower spring 230 and the upper spring 240 .

In the case of the lens driving device 200B shown in FIG. 18 , like the lens driving device 200A shown in FIGS. 13 and 16 , the strength of the magnetic field sensed by the position sensor 260 is linear from B2 to B1. change can be seen.

Referring to FIG. 17 , it can be seen that the maximum displacement D1 that the moving part 220 of the lens driving apparatus 200B shown in FIG. 18 can move is z1-z2.

19 is a cross-sectional view of a lens driving device 200C according to another embodiment.

In the case of the lens driving devices 200A and 200B shown in FIGS. 13, 16 or 18 , the first side surface 252 is positioned above the second side surface 254 . On the other hand, in the case of the lens driving device 200C shown in FIG. 19 , the second side surface 254 may be located on the first side surface 252 . As described above, the lens driving device 200C shown in FIG. 19 except that the long second side surface 252 is disposed below the short first side surface 254 on the side surface of the bipolar magnet 250 . is the same as the lens driving apparatuses 200A and 200B shown in FIG. 13 or 18 , so the same reference numerals are used, and descriptions of overlapping parts will be omitted.

20A and 20B are cross-sectional views, respectively, according to embodiments 250C and 250D of the anode magnetizing magnet 250 shown in FIG. 19 .

Referring to FIG. 20A , the positively polarized magnet 250C may include first and second sensing magnets 250C-1 and 250C-2, or may further include a non-magnetic barrier rib 250C-3. . Referring to FIG. 20B , the positively polarized magnet 250D includes first and second sensing magnets 250D-1 and 250D-2, or may further include a non-magnetic barrier rib 250D-3.

The first and second sensing magnets 250C-1 and 250C-2 shown in FIG. 20A may be spaced apart from each other or disposed in contact with each other, and the first and second sensing magnets 250D-1 shown in FIG. 20B may be disposed in contact with each other. 250D-2) may be disposed to be spaced apart from or in contact with each other.

According to an embodiment, as shown in FIG. 20A , the first and second sensing magnets 250C-1 and 250C-2 are spaced apart from each other or disposed in contact with each other in a direction parallel to the optical axis direction (ie, the z-axis direction). may be

Alternatively, according to another embodiment, as shown in FIG. 20B , the first and second sensing magnets 250D-1 and 250D-2 may be spaced apart or disposed in contact with each other in the magnetization direction (ie, the y-axis direction). have.

Although the anodic magnetizing magnet 250 shown in FIG. 19 is shown to be a magnet having the structure shown in FIG. 20A , it may be replaced with a magnet having the structure shown in FIG. 20B .

In addition, as shown in FIG. 20A , the non-magnetic barrier rib 250C-3 may be disposed between the first and second sensing magnets 250C-1 and 250C-2, and as shown in FIG. 20B , the non-magnetic partition wall 250C-3 may be disposed. The adult partition wall 250D-3 may be disposed between the first and second sensing magnets 250D-1 and 250D-2. The non-magnetic partition walls 250C-3 and 250D-3 are portions that are substantially non-magnetic and may include a section having little polarity, and may be filled with air or include a non-magnetic material.

In addition, the third length L3 of the non-magnetic barrier ribs 250C-3 and 250C-3 is 5% or more or 50 of the total length LT in a direction parallel to the optical axis direction of the anode magnetizing magnets 250C and 250C. % or less.

15 and 19 , in the initial state before moving the lens in the optical axis direction, the intermediate height (z=zh) of the position sensor 260 is the nonmagnetic partition wall 250C-3 in the y-axis direction, which is the magnetization direction. ) (or the space between the first side 252 and the second side 254 ) may be opposite or coincident. This means that the upper end 253 of the first side surface 252 is located on the virtual horizontal plane HS2 extending in the y-axis direction, which is the magnetization direction, from the middle height (z=zh) of the position sensor 260 . can Alternatively, the intermediate height (z=zh) of the position sensor 260 may be located at a point between the upper end 253 and the second side surface 254 .

In this way, in a state in which the moving unit 220 does not move and is stopped, as shown in FIG. 19 , when the positively-polarized magnet 250 and the position sensor 260 are disposed, the second sensed by the position sensor 260 is The strength of the magnetic field having 1 polarity may be '0'.

14A and 20A , the first side surface 252 may correspond to the side surface of the first sensing magnets 250A-1 and 250C-1 facing the position sensor 260 . In addition, as shown in each of FIGS. 14A and 20A , the second side 254 may correspond to the side of the second sensing magnets 250A-2 and 250C-2 facing the position sensor 260 .

Alternatively, as shown in each of FIGS. 14B or 20B , the first and second side surfaces 252 and 254 are side surfaces of the first sensing magnets 250B-1 and 250D-1 facing the position sensor 260 . may correspond to

21 is a cross-sectional view of a lens driving device 200D according to another embodiment.

Referring to FIG. 21 , in the initial state before moving the lens in the optical axis direction, the intermediate height (z=zh) of the position sensor 260 is the first point of the first side surface 252 in the y-axis direction, which is the magnetization direction. can look at Here, the first point may be any point between the upper end and the lower end of the first side surface 252 , for example, an intermediate height of the first side surface 252 .

In a state before the moving part 220 moves, the positively-polarized magnet 250 of the lens driving device 200D shown in FIG. 21 is greater than the positively-polarized magnet 250 of the lens driving device 200C shown in FIG. It may be positioned higher by the distance (z2-zh). In this case, referring to FIG. 15 , the lowest intensity of the magnetic field having the first polarity detected by the position sensor 260 may be B2.

As a current is applied to the first coil of the lens driving device 200D shown in FIG. 21 , the moving unit 220 may rise to the maximum height z1 like the lens driving device 200A. At this time, the maximum height of the moving unit 220 can be adjusted as a mechanical stopper. Alternatively, the maximum height of the moving unit 220 may be changed by adjusting the elastic modulus of the lower spring 230 and the upper spring 240 .

In the case of the lens driving device 200D shown in FIG. 21 , as in the lens driving device 200A shown in FIGS. 13 and 16 , the first polarity detected by the position sensor 260 is the first polarity detected by the position sensor 260 , and the change in the strength of the magnetic field is B2 It can be seen that from B1 to B1 it is linear.

Referring to FIG. 17 , it can be seen that the maximum displacement D1 that the moving part 220 of the lens driving device 200D shown in FIG. 21 can move is z1-z2.

In the above-described lens driving apparatuses 200A, 200B, 200C, and 200D shown in FIGS. 13, 16, 18, 19, and 21, the moving unit 220 moves in one direction of the optical axis, that is, the +z axis from the initial position. You can only move in one direction. However, the embodiment is not limited thereto. That is, according to another embodiment, as a current is applied to the first coil, the lens driving device may move in both directions of the optical axis, ie, in the +z-axis direction or the -z-axis direction from the initial position. The configuration and operation of the lens driving apparatus according to this embodiment will be described as follows.

22 is a cross-sectional view of a lens driving device 200E according to another embodiment.

Unlike the above-described lens driving devices 200A and 200B, the lens driving device 200E shown in FIG. 22 may move in the +z-axis direction or the -z-axis direction from the initial position. Accordingly, the moving part 220 has a shape floating in the air by the lower and upper springs 230 and 240 . Except for this, the components of the lens driving device 200E shown in FIG. 22 are the same as the above-described components of each of the lens driving devices 200A and 200B, and thus detailed overlapping description of each component will be omitted.

Referring to FIG. 22 , in an initial state before moving the lens in the optical axis direction, that is, in a state in which the moving unit 220 does not move and is stopped, the intermediate height (z=zh) of the position sensor 260 is in the magnetization direction. A first point of the first side surface 252 may be viewed. Here, the first point may be any point between the upper end and the lower end of the first side surface 252 , for example, an intermediate height of the first side surface 252 .

23 is a cross-sectional view of a lens driving device 200F according to another embodiment.

Unlike the above-described lens driving devices 200C and 200D shown in FIGS. 19 and 21 , the lens driving device 200F shown in FIG. 23 may move in the +z-axis direction or the -z-axis direction. Accordingly, the moving part 220 has a shape floating in the air by the lower and upper springs 230 and 240 . Except for this, the components of the lens driving device 200F shown in FIG. 23 are the same as the above-described components of each of the lens driving devices 200C and 200D, and thus detailed overlapping descriptions of each component will be omitted.

Referring to FIG. 23 , in the initial state before moving the lens in the optical axis direction, the intermediate height (z=zh) of the position sensor 260 may look at the first point of the first side surface 252 in the magnetization direction. have. Here, the first point may be any point between the upper end and the lower end of the first side surface 252 , for example, an intermediate height of the first side surface 252 .

In the lens driving apparatuses 200E and 200F shown in FIG. 22 or FIG. 23 , the upward and downward motions of the moving unit 220 may be the same as in FIG. 15 . Accordingly, the operation of the lens driving apparatuses 200E and 200F shown in FIGS. 22 and 23 will be described with reference to FIG. 15 .

In the lens driving devices 200E and 200F, in an initial state before moving the lens in the optical axis direction, that is, in a state in which the moving unit 220 is stopped without moving up or down or lowered, or in an initial position, the position sensor 260 When the positively polarized magnet 250 is disposed as shown in FIGS. 22 and 23 , the magnetic field of the first polarity detected by the position sensor 260 may be B3. In a state in which the moving unit 220 is stopped without moving up or down or lowered, or in an initial position, the initial magnetic field value sensed by the position sensor 260 is the separation distance between the position sensor 260 and the positive magnetizing magnet 250, etc. 260, 250) may be changed or adjusted according to the design values.

24 is a graph showing the displacement of the moving unit 220 according to the current supplied to the first coil in the lens driving apparatuses 200E and 200F shown in FIGS. 22 and 23 . The horizontal axis is the current supplied to the first coil. and the vertical axis represents displacement. In addition, the right side of the horizontal axis with respect to the vertical axis may mean a constant current, a forward current, or a + current, and the left side of the horizontal axis may mean a reverse current, a reverse current, or a - current.

As the moving unit 220 increases the intensity of the constant current applied to the first coil in a stopped state or initial position without moving as in FIG. 22 or 23, the moving unit 220 moves the distance in the +z-axis direction. Up to (z=z4) can be raised and lowered. In this case, referring to FIG. 15 , the strength of the magnetic field sensed by the position sensor 260 may increase from B3 to B4.

Alternatively, the moving unit 220 increases the strength of the reverse current applied to the first coil in a stopped state or an initial position without moving as in FIG. 22 or 23 , or after moving in the +z-axis direction When the constant current supplied to one coil is reduced, the moving unit 220 may move downward. In this case, referring to FIG. 15 , the strength of the magnetic field sensed by the position sensor 260 may decrease from B3 to B5 or decrease from B4 to B3.

As such, it can be seen that the intensity of the magnetic field having the first polarity sensed by the position sensor 260 of the lens driving devices 200E and 200F illustrated in FIG. 22 or 23 varies linearly between B5 and B4.

Referring to FIG. 24 , in a situation where the moving unit 200 can move in both directions as described above, the upper displacement width D3 and the lower displacement width D2 of the moving unit 220 may be the same, or the upper displacement The width D3 may be larger than the lower displacement width D2.

If the upper displacement width D3 is the same as the lower displacement width D2, in the initial state before moving the lens in the optical axis direction, the middle height (z=zh) of the position sensor 260 is the magnetization direction. It may coincide with the above-described first point in the y-axis direction. However, if the upper displacement width D3 is larger than the lower displacement width D2, the intermediate height (z=zh) of the position sensor 260 in the initial state or initial position before moving the lens in the optical axis direction. may look at the second point higher than the first point in the y-axis direction, which is the magnetization direction. That is, when the upper displacement width D3 is greater than the lower displacement width D2 than when the upper displacement width D3 is the same as the lower displacement width D2, the position sensor 260 for the positively magnetized magnet 250 is The height may be relatively higher.

In this case, the difference between the second point and the first point may be expressed as Equation 1 below.

Here, H2 is the height of the second point, H1 is the height of the first point, ΔD is the value obtained by subtracting the lower displacement width D2 from the upper displacement width D3 of the moving unit 220 , and D is the movement It may mean the displacement width (D2+D3) of the part 220 .

25 shows the intensity of the magnetic field (or output voltage) sensed by the position sensor 260 according to the moving distance of the moving unit 220 in the optical axis direction. -2) as opposed to each other, the vertical axis indicates the strength of the magnetic field (or output voltage), and the horizontal axis indicates the moving distance of the moving unit 220 in the optical axis direction.

In the case of the graph shown in FIG. 25 , the structure of the positive magnetizing magnet 250 facing the position sensor 260 corresponds to the first and second sensing magnets 250A-1 and 250A-2 shown in FIG. 14A . do. However, instead of the first and second sensing magnets 250A-1 and 250A-2 shown in FIG. 14A, the first and second sensing magnets 250B-1 and 250B-2 shown in FIG. 14B or FIG. The first and second sensing magnets 250C-1 and 250C-2 shown in 20A or the first and second sensing magnets 250D-1 and 250D-2 shown in FIG. 20B are combined with the position sensor 260 . It goes without saying that the following description with respect to FIG.

Referring to FIG. 25 , as described above, the magnetic field sensed by the position sensor 260 and having a linearly varying intensity may be the magnetic field 272 of the first polarity, for example, the S pole. However, the embodiment is not limited thereto. That is, according to another embodiment, the magnetic field sensed by the position sensor 260 and having a linearly varying intensity may be the second polarity, for example, the magnetic field 274 of the N pole.

If the magnetic field having a linearly varying intensity sensed by the position sensor 260 is not the first polarity but the N-pole magnetic field 274 of the second polarity, referring to FIG. 25 , the lens is moved in the optical axis direction z In the initial state or initial position before moving in the axial direction, the intermediate height (z=zh) of the position sensor 260 may look at the first point of the second side surface 254 . Here, the first point may be any point between the upper end and the lower end of the second side surface 254 , for example, an intermediate height of the second side surface 254 . Thereafter, when the lens is moved the highest in the +z-axis direction, which is the optical axis direction, the middle height (z=zh) of the position sensor 260 may coincide with a point lower than the lower end of the second side surface 254 .

In addition, the first section BP1 in which the magnetic field 272 of the S pole is linear is greater than the second section BP2 in which the magnetic field 274 of the N pole is linear. This is because the first length L1 of the first side surface 252 having the S polarity is longer than the second length L2 of the second side surface 254 having the N polarity. However, the first side surface 252 having a first length L1 that is longer than the second length L2 has an N-polarity, and a second side 252 having a second length L2 that is shorter than the first length L1. When the side 254 has an S polarity, reference numeral 272 shown in FIG. 25 may correspond to an N-polarity magnetic field, and 274 may correspond to an S-polarity magnetic field. Although not shown, when the pole is changed as described above, the polarity of the Y-axis may be reversed.

26A and 26B are graphs illustrating displacements for each intensity of a magnetic field sensed by the position sensor 260 . In each graph, a horizontal axis indicates a magnetic field, and a vertical axis indicates displacement.

If the position sensor 260 and the bipolar magnet 250 are disposed to detect the magnetic field of the first section BP1 having a larger linear section than the second section BP2 shown in FIG. 25 . , it is possible to recognize the displacement even when the change in the sensed magnetic field is minute as shown in FIG. 26A . However, relatively, in order to sense the magnetic field of the second section BP2 having a smaller linear section than the first section BP1 shown in FIG. 25 , the position sensor 260 and the bipolar magnet 250 are connected In the case of arrangement, as shown in FIG. 26B , when the change in the sensed magnetic field is minute, the degree of recognizing a minute displacement is smaller than in the case of FIG. 26A . That is, the slope of FIG. 26A and FIG. 26B may be different from each other. Therefore, as shown in FIG. 26A , the position sensor 260 and the quantum magnetization magnet 250 are disposed so that the position sensor 260 detects the magnetic field of the first section BP1 larger than the second section BP2. In this case, displacement can be detected with much higher resolution. That is, the wider the linear section in which the strength of the magnetic field changes, the more accurately the change in displacement with respect to the coded magnetic field can be checked.

In addition, according to an embodiment, the strength of the magnetic field sensed by the position sensor 260 and having a linearly varying magnitude may be coded in 7 bits to 12 bits. In this case, the controller (not shown) may include a look-up table (not shown) to precisely control the displacement of the moving unit 220 through the position sensor 260 . In the lookup table, code values for each strength of a magnetic field may be matched to displacement and stored. For example, referring to FIG. 15 , the strength of the magnetic field from the minimum magnetic field B0 to the maximum magnetic field B1 may be coded as 7 bits to 12 bits by matching the displacement z. Therefore, when it is desired to control the displacement of the moving unit 220, a corresponding code value is found, and the controller may move the moving unit 220 in the optical axis direction to a position matching the found code value. Such a control unit may be disposed or included in the image sensor, or may be disposed or included in the first circuit board on which the image sensor is mounted.

In addition, in the above-described lens driving apparatuses 200A to 200F, the length LT in the z-axis direction parallel to the optical axis direction of the anode magnetizing magnet 250 is 1.5 times the movable width of the moving part 220 , that is, the maximum displacement. may be more than For example, referring to FIGS. 13 and 16 , since the maximum displacement that is the movable width of the moving part 220 is z1 , the length LT of the positively polarized magnet 250 may be 1.5*z1 or more.

In addition, the position sensor 260 is coupled to, contacted, supported, temporarily fixed, inserted or seated in the fixed part 210 in the above-described lens driving device 200A to 200F, and the positively-polarized magnet 250 is located in the moving part 220 . ) is coupled, contacted, supported, fixed, temporarily fixed, inserted or seated as an example. However, the embodiment is not limited thereto.

That is, according to another embodiment, the position sensor 260 is coupled, contacted, supported, temporarily fixed, inserted or seated in the moving unit 220 , and the positively-polarized magnet 250 is coupled to the fixed unit 210 , contacting the moving unit 220 . , may be supported, fixed, temporarily fixed, inserted or seated, in which case the above description may be applied.

27 is a graph for explaining a change in the intensity of a magnetic field according to a moving distance of the moving unit 220 of the lens driving apparatus of the comparative example, wherein the horizontal axis represents the moving distance and the vertical axis represents the magnetic field intensity.

If the position sensor 260 is not disposed so as to be close to either one of the first and second side surfaces 252 and 254 of the bipolar magnet 250 , the first and second lengths L1 and L2 in the optical axis direction ), the change in the magnetic field sensed by the position sensor 260 as the moving unit 220 moves may be as shown in FIG. 27 . At this time, referring to FIG. 27 , the magnetic field sensed by the position sensor 260 has opposite polarities around a mutual zone (MZ). In this case, the mutual region MZ is a region in which the strength of the magnetic field sensed by the position sensor 260 is fixed to '0' despite the movement of the moving unit 220 . Such a mutual region MZ may not be able to be processed even by software. Therefore, the position sensor 260 has no choice but to detect the magnetic field strength as '0' in the mutual region MZ, and accurately measures and controls the moving distance of the moving unit 220 moving in this section MZ. Can not.

However, according to the embodiment, the first length (L1) of the positively polarized magnet 250 is formed longer than the second length (L2), and the position sensor 260 generates a magnetic field of the first polarity with a linearly changing intensity. Since it is detected, the same problem as in the above-described comparative example can be prevented in advance. Accordingly, the design margin and reliability of the lens driving devices 200A to 200F can be improved.

28 is a graph illustrating a change in the magnetic field sensed by the position sensor 260 according to the movement of the moving unit 220 in the lens driving apparatus according to the embodiment, in which the horizontal axis represents the moving distance and the vertical axis represents the magnetic field.

If the third length L3 of the aforementioned non-magnetic partition walls 250A-1 and 250C-1 is reduced to 50% or less of the total length LT of the positive electrode magnet 250, as shown in FIG. Likewise, the mutual region MZ can be almost eliminated. In this case, the middle height (z=zh) of the position sensor 260 may coincide with the middle height of the positively-polarized magnet 250 . In this case, the change in the intensity of the magnetic field 282 of the first polarity and the change in the intensity of the magnetic field 284 of the second polarity may vary substantially linearly. Accordingly, since the position sensor 260 can detect both the magnetic field 282 of the first polarity and the magnetic field 284 of the second polarity, which linearly change in strength according to the movement of the moving unit 220 , the first and a magnetic field having a linearly varying intensity having only one polarity among the second polarities may have a relatively higher resolution than when the position sensor 260 detects the magnetic field.

In addition, when the third length L3 of the non-magnetic barrier ribs 250A-1 and 250C-1 is 10% or more of the total length LT of the anode magnetizing magnet 250, the mutual region MZ of the magnetic field and Since the linear section is clearly separated, the position sensor 260 may detect only a magnetic field having one of the first and second polarities and having a linearly varying intensity.

On the other hand, the lens driving apparatus 100, 200A to 200F according to the above-described embodiment may be used in various fields, for example, a camera module. For example, the camera module may be applied to a mobile device such as a mobile phone.

The camera module of the embodiment includes the above-described lens driving device 100, 200A to 200F, and a lens mounted, inserted, seated, contacted, coupled, fixed, supported or disposed in the lens driving device 100, 200A to 200F, and a lens; It may include an image sensor (not shown), a second circuit board (not shown) on which the image sensor is disposed (or a main circuit board), and an optical system. In this case, the camera module according to the embodiment may further include a lens barrel coupled to the bobbin 110 .

The lens barrel may be the same as described above, and the second circuit board may form a bottom surface of the camera module from a portion on which the image sensor is mounted. In addition, the optical system may include at least one or more lenses that transmit an image to the image sensor.

In addition, the camera module may further include a camera module controller (not shown). In this case, the focal length of the lens according to the distance between the object and the lens may be compared with the first displacement value calculated based on the current change value or the code value detected by the displacement sensor 180 or the position sensor 260 . . Thereafter, when the first displacement value or the current position of the lens and the focal length of the lens do not correspond, the camera module control unit determines the amount of current or code value applied to the first coil 120 of the bobbin 110 or the moving unit 220 . By readjusting, the bobbin 110 or the moving unit 220 may be moved by the second displacement amount in the first direction. In addition, for sensing in which the displacement detecting unit 180 or the position sensor 260 fixedly coupled to the fixed housing member 140 or the fixed unit 210 is fixedly coupled to the moving bobbin 110 or the moving unit 220 . By sensing the change in the intensity of the magnetic field emitted from the sensing magnet 182 or the bipolar magnetizing magnet 250 according to the first direction movement of the magnet 182 or the polarizing magnet 250, the amount of change in the detected magnetic field intensity The current position or the first displacement amount of the bobbin 110 or the moving unit 220 may be calculated or determined in a separate driver IC or camera module controller based on the output current change amount or the mapped code value. In this way, the current position or the first displacement amount of the bobbin 110 or the moving unit 220 calculated or determined using the displacement detecting unit 180 or the position sensor 260 is transmitted to the control unit of the first circuit board 170, , so that the control unit can maintain the code value by re-determining the position of the bobbin 110 or the moving unit 220 for auto-focusing. The amount of current applied here may output a different value depending on the posture and situation, and the amount of current applied to the first coil 120 may be adjusted.

Meanwhile, an actuator module capable of performing an auto-focusing function and an image stabilization function may be installed in the optical system. The actuator module performing the auto-focusing function may be configured in various ways, and a voice coil unit motor is generally used a lot. The lens driving apparatuses 100 and 200A to 200F according to the above-described embodiment may correspond to an actuator module that performs an auto-focusing function. However, the embodiment is not limited to the actuator module performing the auto-focusing function, and may also be applied to the actuator module performing both the auto-focusing function and the hand-shake correction function.

Although not shown, a second coil (not shown), a support member (not shown), and a plurality of sensing units (not shown) are provided to the lens driving devices 100 and 200A to 200F that perform the above-described auto-focusing function. In addition, the lens driving devices 100 , 200A to 200F may perform an auto-focusing function as well as a hand-shake correction function. Here, the second coil is disposed so that the bottom surface of the driving magnet 130 directly faces the second coil, and each of the plurality of sensing units may be implemented as, for example, a Hall sensor, and each of the plurality of sensing units and the second coil The two coils and the driving magnet may be disposed on the same axis. Accordingly, the second coil may perform handshake correction by moving the housing member 140 in the second and/or third directions through interaction with the driving magnet 130 .

In this case, a support member is disposed on the upper surface of the base 190 to elastically (or elastically) support the horizontal operation of the housing member 140 moving in a direction perpendicular to the first direction.

In addition, the camera module may further include an infrared cut filter (not shown). The infrared cut filter serves to block light in the infrared region from being incident on the image sensor. In this case, in the base 190 illustrated in FIG. 2 , an infrared cut filter may be installed at a position corresponding to the image sensor, and may be coupled to a holder member (not shown). In addition, the base 190 may support the lower side of the holder member.

A separate terminal member may be installed in the base 190 to conduct electricity with the second circuit board, and it is also possible to integrally form the terminal using a surface electrode or the like. Meanwhile, the base 190 may function as a sensor holder to protect the image sensor, and in this case, a protrusion may be formed in a downward direction along the side surface of the base 190 . However, this is not an essential configuration, and although not shown, a separate sensor holder may be disposed under the base 190 to perform its role.

In the above, the embodiment has been mainly described, but this is only an example and does not limit the present invention, and those of ordinary skill in the art to which the present invention pertains are not exemplified above in the range that does not depart from the essential characteristics of the present embodiment. It will be appreciated that various modifications and applications are possible. For example, each component specifically shown in the embodiment can be implemented by modification. And differences related to such modifications and applications should be construed as being included in the scope of the present invention defined in the appended claims.

100, 200A to 200F: Lens drive unit 102: Cover can
104: first groove 106: third groove
108: can protrusion 110: bobbin
112: upper escape groove 118: lower escape groove
113: upper support protrusion 114: lower support protrusion
116: seating groove for coil 117: receiving groove
117b: adhesive groove 120: first coil
130, 131, 132: magnet for driving 140: housing member
141: side of the housing member 141a, 141a': a through hole for the magnet
141b: through hole for sensor 143: first stopper
144: upper frame supporting projection 147: lower frame supporting projection
148: lower guide groove 149: protrusion for mounting
150: upper elastic member 151, 161: inner frame
151a: second through hole 152, 162: outer frame
153, 163: connecting portion 152a: first through hole
155: guide groove 160, 160a, 160b: lower elastic member
161a: third through hole 162a: fastening part
170: first circuit board 171: terminal of the first circuit board
172: various pins 173: through hole for mounting
180: displacement detection unit 182: magnet for sensing
190: base 192: second groove
194: guide member 210: fixed portion
220: moving part 230: lower spring
232: first lower spring 234: second lower spring
240: upper spring 242: first upper spring
244: second upper spring
250, 250A ~ 250D: Bipolar Magnet
252: first side 254: second side
250A-1 ~ 250D-1: Magnet for first sensing
250A-2 ~ 250D-2: Magnet for second sensing
250A-3 to 250D-3: Non-magnetic bulkhead 260: Position sensor

Claims (28)

a cover can comprising a top plate and a plurality of side plates extending from the top plate;
a bobbin disposed within the cover can;
a base coupled to the side plate of the cover can;
a coil disposed on the bobbin;
a driving magnet disposed between the coil and the side plate of the cover can;
a sensing magnet disposed on the bobbin; and
A position sensor for detecting the sensing magnet,
The plurality of side plates of the cover can include first and second side plates disposed opposite to each other, and third and fourth side plates disposed between the first and second side plates and disposed opposite to each other,
The driving magnet includes a first magnet disposed on the first side plate of the cover can and a second magnet disposed on the second side plate of the cover can,
The driving magnet is not disposed on the third side plate and the fourth side plate of the cover can,
The sensing magnet is disposed on the first surface of the bobbin corresponding to the third side plate of the cover can,
At least a portion of the coil is disposed between the sensing magnet and the position sensor. According to claim 1,
The coil is disposed between the sensing magnet and the position sensor in an optical axis direction and a direction perpendicular to the third side plate. According to claim 1,
The sensing magnet is disposed on the coil and the bobbin in an optical axis direction and a direction perpendicular to the third side plate. According to claim 1,
The sensing magnet is a lens driving device overlapping the coil in an optical axis direction and a direction perpendicular to the third side plate. According to claim 1,
The bobbin includes a first groove formed on an outer circumferential surface of the bobbin, and a second groove recessed from the first groove,
The coil is disposed in the first groove of the bobbin,
The sensing magnet is a lens driving device disposed in the second groove of the bobbin. 6. The method of claim 5,
An adhesive for fixing the sensing magnet to the bobbin is disposed in the second groove of the bobbin. 6. The method of claim 5,
The bobbin includes a third groove formed at a position symmetrical to the second groove with respect to the center of the bobbin,
A lens driving device in which a weight balancing member is disposed in the third groove of the bobbin. According to claim 1,
The sensing magnet includes first and second sensing magnets,
The first sensing magnet is disposed on the second sensing magnet in the optical axis direction,
Each of the first and second sensing magnets includes an N pole and an S pole. 9. The method of claim 8,
In an initial state in which no current is applied to the coil, a center of the position sensor is disposed at a height corresponding to an upper end of the first sensing magnet. 10. The method of claim 9,
A length of the first sensing magnet in the optical axis direction is longer than a length of the second sensing magnet in the optical axis direction. 9. The method of claim 8,
In an initial state in which no current is applied to the coil, the center of the position sensor is disposed at a height corresponding to the second sensing magnet,
A length of the second sensing magnet in the optical axis direction is longer than a length of the first sensing magnet in the optical axis direction. 9. The method of claim 8,
The sensing magnet includes a non-magnetic barrier rib disposed between the first and second sensing magnets. 13. The method of claim 12,
In an initial state in which no current is applied to the coil, the center of the position sensor is disposed at a height corresponding to the non-magnetic barrier rib. circuit board;
an image sensor placed on the circuit board; and
A camera module comprising the lens driving device of claim 1 . A smartphone comprising the camera module of claim 14 . a cover can comprising a top plate and a plurality of side plates extending from the top plate;
a bobbin disposed within the cover can;
a base coupled to the side plate of the cover can;
a coil disposed on the bobbin;
a driving magnet disposed between the coil and the side plate of the cover can;
a sensing magnet disposed on the bobbin; and
A position sensor for detecting the sensing magnet,
The plurality of side plates of the cover can include first and second side plates disposed opposite to each other, and third and fourth side plates disposed between the first and second side plates and disposed opposite to each other,
The driving magnet includes a first magnet disposed on the first side plate of the cover can and a second magnet disposed on the second side plate of the cover can,
The driving magnet is not disposed on the third side plate and the fourth side plate of the cover can,
The sensing magnet is disposed on the first surface of the bobbin corresponding to the third side plate of the cover can,
At least a portion of the sensing magnet is disposed between the coil and the bobbin in an optical axis direction and a direction perpendicular to the third side plate. 17. The method of claim 16,
The sensing magnet is a lens driving device overlapping the coil in an optical axis direction and a direction perpendicular to the third side plate. 17. The method of claim 16,
The bobbin includes a first groove formed on an outer circumferential surface of the bobbin, and a second groove recessed from the first groove,
The coil is disposed in the first groove of the bobbin,
The sensing magnet is a lens driving device disposed in the second groove of the bobbin. 19. The method of claim 18,
The bobbin includes a third groove formed at a position symmetrical to the second groove with respect to the center of the bobbin,
A lens driving device in which a weight balancing member is disposed in the third groove of the bobbin. 17. The method of claim 16,
The sensing magnet includes first and second sensing magnets, and a non-magnetic barrier rib disposed between the first and second sensing magnets. delete delete delete delete delete delete delete delete

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