KR102583322B1 - Lens moving apparatus - Google Patents

Abstract

This embodiment relates to a lens driving device, and more specifically, to a lens driving device that can improve the space efficiency of the bobbin and shorten the focus alignment time of the lens by feeding back the amount of displacement in the optical axis direction of the lens.
Specifically, this embodiment includes a hollow column-shaped housing supporting a driving magnet; At least one lens is installed on the inside, a coil disposed inside the driving magnet is provided on the outer peripheral surface, and an electromagnetic interaction between the driving magnet and the coil causes the lens to move parallel to the optical axis inside the housing. a bobbin moving in a first direction; It relates to a lens driving device including a displacement detection unit that determines a first displacement value of the bobbin in the first direction.

Description

Lens moving device {LENS MOVING APPARATUS}

This embodiment relates to a lens driving device, and more specifically, to a lens driving device that can improve the space efficiency of the bobbin and shorten the focus alignment time of the lens by feeding back the amount of displacement in the optical axis direction of the lens.

Recently, the development of IT products such as mobile phones, smartphones, tablet PCs, and laptops with built-in ultra-small digital cameras is actively underway.

In the case of IT products that have a conventional ultra-small digital camera built-in, there is a built-in lens driving device that adjusts the distance between the image sensor that converts external light into a digital image or a digital image and the lens to align the focal length of the lens.

However, conventional ultra-small digital cameras have a problem in that they require a lot of autofocus time to perform the autofocus function.

U.S. Patent Publication No. 2012/0314307 (Publication date: 2012.12.13.) Korean Patent Publication No. 10-2013-0060535 (Publication Date: 2013.06.10.)

Therefore, the purpose of this embodiment is to provide a lens driving device that solves the problems of the prior art.

Specifically, the purpose of this embodiment is to provide a lens driving device that can shorten the autofocus time of the lens.

Additionally, the purpose of this embodiment is to provide a lens driving device that can more accurately and quickly position the lens at the focal length of the lens.

Additionally, the purpose of this embodiment is to provide a lens driving device that improves the autofocus function and at the same time improves space efficiency and durability of the lens driving device.

According to one embodiment of the present embodiment, the present embodiment includes a hollow column-shaped housing supporting a driving magnet; a bobbin having a coil disposed inside the driving magnet on the outer peripheral surface and moving in a first direction parallel to the optical axis within the housing due to electromagnetic interaction between the driving magnet and the coil; A lens driving device including a displacement detection unit that determines a first displacement value of the bobbin in the first direction may be provided.

In addition, preferably, it may further include a printed circuit board installed on one side of the housing.

Also, preferably, the displacement detection unit may include a sensing magnet provided in the bobbin, and a position sensor provided in the housing at a position corresponding to the sensing magnet.

In addition, preferably, first and second driving magnets are provided on each of the two opposing sides of the housing, and a position sensor is provided on one side of the housing perpendicular to the two sides or a side other than the two sides. It can be characterized as:

In addition, preferably, first and second driving magnets are provided on each of opposite two sides of the housing, and a third driving magnet and A position detection sensor disposed at a predetermined distance from the third driving magnet may be provided, and a fourth driving magnet may be provided on the other side of the housing facing the one side.

Also, preferably, the driving magnet provided on one side and the driving magnet provided on the other side may be arranged symmetrically with respect to the center of the housing.

Also, preferably, the bobbin may further include a receiving groove formed inward at a predetermined depth on the outer peripheral surface of the bobbin to accommodate the sensing magnet.

Additionally, preferably, at least a portion of the receiving groove may be located inside the coil.

Also, preferably, the receiving groove may be characterized in that the depth between the inner surface on which one surface of the sensing magnet is supported and the outer peripheral surface on which the coil is provided is less than or equal to the thickness of the sensing magnet.

Additionally, preferably, the receiving groove may include an opening communicating with the receiving groove on one of the lower and upper surfaces of the bobbin.

In addition, preferably, the receiving groove includes an inner surface on which one surface of the sensing magnet is supported, and an adhesive groove formed concave inward by a predetermined depth than the inner surface so that adhesive can be injected. You can do this.

Also, preferably, the adhesive groove may include a first additional groove formed longer than the length of the sensing magnet in the vertical thickness direction of the bobbin.

Also, preferably, the receiving groove has an opening communicating with the receiving groove on one of the lower and upper surfaces of the bobbin, and the adhesive groove is located in a predetermined direction from the opening to the inside of the bobbin. It may be characterized by having a second additional groove formed deeply.

Also, preferably, the bobbin has an additional accommodation formed inward at a predetermined depth on the outer peripheral surface of the bobbin at a position symmetrical to the receiving groove with respect to the center of the bobbin on the outer peripheral surface facing the outer peripheral surface where the receiving groove is formed. It may further include a groove and a weight balance member accommodated in the additional receiving groove and having the same weight as the magnetic force sensing member.

Also, preferably, the inner frame may be coupled to the bobbin, and the outer frame may further include an upper elastic member and a lower elastic member coupled to the housing.

According to the above-mentioned problem solving means, the present embodiment can shorten the focus alignment time of the lens by feedbacking the amount of displacement in the optical axis direction of the lens and readjusting the position of the lens in the optical axis direction.

In addition, this embodiment can minimize the gap between the sensing magnet provided in the bobbin, which is a moving body, and the position detection sensor provided in the housing, which is fixed, and this allows more accurate detection of the amount of displacement in the direction of the optical axis of the lens. It can be positioned more accurately and quickly at the focal length of the lens.

In addition, in this embodiment, by providing a sensing magnet inside the bobbin and a position detection sensor inside the housing, no separate space is required for mounting the displacement detection unit, thereby improving space efficiency of the camera module (especially the bobbin). It can be improved.

1 is a schematic perspective view of a lens driving device according to an embodiment of the present invention;
Figure 2 is a schematic exploded perspective view of a lens driving device according to an embodiment of the present embodiment;
Figure 3 is a schematic perspective view of the lens driving device in Figure 1 with the cover member removed;
Figure 4 is a schematic plan view of Figure 3,
5 is a schematic perspective view of a housing according to one embodiment of the present embodiment;
Figure 6 is a schematic perspective view of the housing viewed from a different angle than Figure 5;
7 is a schematic bottom perspective view of a housing according to one embodiment of the present embodiment;
8 is a schematic exploded perspective view of a housing according to one embodiment of the present embodiment;
Figure 9 is a schematic plan view of the upper elastic member according to one embodiment of the present embodiment,
Figure 10 is a schematic plan view of the lower elastic member according to one embodiment of the present embodiment;
11 is a schematic perspective view of a bobbin according to one embodiment of the present embodiment,
Figure 12 is a schematic bottom perspective view of a bobbin according to an embodiment of the present embodiment;
Figure 13 is a schematic exploded perspective view of a bobbin according to one embodiment of the present embodiment;
Figure 14 is a partially enlarged perspective view of Figure 13;
Figure 15 is a partially enlarged bottom view of Figure 13;
Figure 16 is a schematic partial enlarged perspective view of the receiving groove according to one embodiment of the present embodiment;
Figure 17 is a schematic longitudinal cross-sectional view of a bobbin according to one embodiment of the present embodiment.

Hereinafter, preferred embodiments of this embodiment will be described with reference to the accompanying drawings so that those skilled in the art can easily implement them. It may be noted that the drawing numbers indicated on the components in the attached drawings are the same as possible when indicating the same composition in other drawings. Additionally, when describing the present embodiment, if it is determined that a detailed description of a related known function or known configuration may unnecessarily obscure the gist of the present embodiment, the detailed description may be omitted. Additionally, some features presented in the drawings are enlarged, reduced, or simplified for ease of explanation, and the drawings and their components are not necessarily drawn to appropriate scale. However, those skilled in the art will easily understand these details.

For reference, in FIGS. 1 to 17, a rectangular coordinate system (x, y, z) can be used. In the drawing, the x-axis and y-axis refer to a plane perpendicular to the optical axis. For convenience, the optical axis direction (z-axis direction) may be referred to as the first direction, the x-axis direction may be referred to as the second direction, and the y-axis direction may be referred to as the third direction. .

FIG. 1 is a schematic perspective view of the lens driving device 100 according to an embodiment of the present embodiment, FIG. 2 is a schematic exploded perspective view of the lens driving device 100 according to an embodiment of the present embodiment, and FIG. 3 is 1 is a schematic perspective view of the lens driving device 100 with the cover member 300 removed, FIG. 4 is a schematic plan view of FIG. 3, and FIG. 5 is a schematic view of the housing 140 according to one embodiment of the present embodiment. It is a perspective view, Figure 6 is a schematic perspective view of the housing 140 as seen from a different angle than Figure 5, Figure 7 is a schematic bottom perspective view of the housing 140 according to one embodiment of the present embodiment, and Figure 8 is the main perspective view. It is a schematic exploded perspective view of the housing 140 according to an embodiment of the present embodiment, Figure 9 is a schematic plan view of the upper elastic member 150 according to an embodiment of the present embodiment, and Figure 10 is an embodiment of the present embodiment. This is a schematic plan view of the lower elastic member 160 according to .

The lens driving device 100 according to this embodiment is a device that adjusts the distance between the lens and the image sensor in the camera module so that the image sensor is located at the focal length of the lens. That is, the lens driving device 100 is a device that performs an auto focusing function.

As shown in FIGS. 1 to 4, the lens driving device 100 according to this embodiment includes a cover member 300, an upper elastic member 150, a bobbin 110, and a The coil 120, the housing 140, the driving magnet 130 and the printed circuit board 170 provided in the housing 140, the lower elastic member 160, the base 210, and the bobbin 110. It may include a displacement detection unit that determines the amount of displacement in the optical axis direction (i.e., first direction).

The cover member 300 has an overall box shape and may be configured to be coupled to the upper part of the base 210. The cover member 300 includes an upper elastic member 150, a bobbin 110, a coil 120 provided on the bobbin 110, a housing 140, and an upper elastic member 150 in a receiving space formed together with the base 210. The driving magnet 130 and the printed circuit board 170 provided in 140 can be accommodated.

The cover member 300 may have an opening on its upper surface that allows the lens coupled to the bobbin 110 to be exposed to external light. Additionally, the opening may be provided with a window made of a light-transmissive material, thereby preventing foreign substances such as dust or moisture from penetrating into the interior of the camera module.

The cover member 300 may include a first groove 310 at the bottom. At this time, as will be described later, the base 210 is formed at a portion in contact with the first groove 310 (i.e., a position corresponding to the first groove 310) when the cover member 300 and the base are combined. 2 A groove portion 211 may be provided. When the cover member 300 and the base are combined, a groove of a certain area may be formed through the combination of the first groove 310 and the second groove 211. An adhesive member having viscosity may be applied to this groove. That is, the adhesive member applied to the groove fills the gap between the opposing surfaces of the cover member 300 and the base 210 through the groove, so that the cover member 300 is connected to the base 210. When combined with, the space between the cover member 300 and the base 210 can be sealed, and also, when the cover member and the base are combined, the sides can be sealed.

Additionally, a third groove 320 may be formed on a surface of the cover member 300 corresponding to the terminal surface of the printed circuit board 170 to prevent interference with a plurality of terminals formed on the terminal surface. The third groove 320 may be formed concavely on the entire surface facing the terminal surface, and the adhesive member is applied inside the third groove to attach the cover member 300, the base 210, and the printed circuit board ( 170) can be sealed, and the sides can be sealed when the cover member and the base are combined.

Meanwhile, the first groove 310 to the third groove 320 are formed on the base 210 and the cover member 300, respectively, but this is not limited, and may be formed in a similar shape only on the base 210. , may be configured to be formed only on the cover member 300.

The base 210 may be provided in an overall square shape, and may be combined with the cover member 300 to form an accommodating space for the bobbin 110 and the housing 140.

A stepped portion protruding outward by a predetermined thickness may be provided to surround the lower edge of the base 210. The predetermined thickness of the stepped portion is the same as the side thickness of the cover member 300, and when the cover member 300 is coupled to the base 210, the side of the cover member 300 is the upper portion of the stepped portion. Or it may be seated or in contact with or placed or coupled to the side. Due to this, it is possible to guide the cover member 300 coupled to the upper side of the step portion, and also, the end of the cover member 300 can be coupled to surface contact, and the end of the cover member is connected to the bottom or side. It can be included. At this time, the stepped portion and the end of the cover member 300 may be adhesively fixed and sealed using an adhesive or the like.

A second groove 211 may be formed in the stepped portion at a position corresponding to the first groove 310 of the cover member 300. As described above, the second groove 211 is combined with the first groove 310 of the cover member 300 to form a groove and can form a space filled with the adhesive member.

The base 210 may have an opening near the center. The opening may be formed at a position corresponding to the position of the image sensor disposed on the camera module.

Additionally, the base 210 may include four guide members 216 that protrude at right angles at a predetermined height upward from the four corners. The guide member may have a polygonal pillar shape. The guide member 216 may be inserted, fastened, or coupled to the lower guide groove 148 of the housing 140, which will be described later. In this way, when the housing 140 is seated or placed on the upper part of the base 210 due to the guide member 216 and the lower guide groove 148, the housing 140 on the base 210 is coupled. It is possible to guide the position, and at the same time, it is possible to prevent the housing 140 from being deviated from the reference position where it should be mounted due to vibration during the operation of the lens driving device 100 or an operator's mistake during the assembly process.

As shown in FIGS. 4 to 9 , the housing 140 may have an overall hollow pillar shape (for example, a hollow square pillar shape as shown in the drawings). The housing 140 is configured to support at least two driving magnets 130 and a printed circuit board 170, and the bobbin 110 inside is movable in a first direction with respect to the housing 140. The bobbin 110 can be accommodated.

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

As shown in FIG. 9, each of the two opposing sides of the four sides 141 of the housing 140 is provided with a through hole 141a or groove for the magnet where the driving magnet 130 is seated, placed, or fixed. It can be. The through hole 141a or groove for the magnet may have a size and shape corresponding to the driving magnet 130, and may also have a shape capable of guiding. A first driving magnet 131 and a second driving magnet 132, that is, a total of two driving magnets 130, may be installed in each of the magnet through-holes 141a.

And, among the four sides 141 of the housing 140, one side perpendicular to the two sides or a side other than the two sides has a through hole for a sensor into which a position sensor 180, to be described later, is inserted, placed, fixed, or seated. (141b) may be provided. The sensor through-hole 141b preferably has a size and shape corresponding to the position sensor 180, which will be described later. Additionally, on one side, at least one mounting protrusion 149 may be provided to allow the printed circuit board 170 to be mounted, placed, temporarily fixed, or fixed. The mounting protrusion 149 is inserted into the mounting through-hole 173 formed on the printed circuit board 170, which will be described later, and at this time, the mounting through-hole 173 and the mounting protrusion 149 are shape-fit. It can be said that it is desirable to be combined in a way or an interference fit method, but it can also serve only as a simple guide.

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

As an additional embodiment of the housing 140, each of the two opposing sides of the four sides 141 of the housing 140 has through holes for first and second magnets in which the driving magnet 130 is seated, placed, or fixed. (141a) (141a') may be provided. In addition, among the four sides 141 of the housing 140, one side perpendicular to the two sides or a side other than the two sides has a third magnet through hole and a sensor spaced apart from the third magnet through hole by a predetermined distance. A through hole 141b may be provided. In addition, among the four sides 141 of the housing 140, the other side facing the one side may be provided with a through hole for a fourth magnet.

That is, the four sides 141 of the housing 140 may be provided with four through-holes for magnets and one through-hole 141b for a sensor.

At this time, the first magnet through-hole 141a and the second magnet through-hole 141a' have the same size and shape, and are (almost) the same throughout the lateral length of the side of the housing 140. It has a lateral length. On the other hand, the through hole for the third magnet and the through hole for the fourth magnet have the same size and shape, and are larger than the through hole for the first magnet (141a) and the through hole for the second magnet (141a'). The lateral length may be formed to be small. This is to secure space for the sensor through-hole 141b because the sensor through-hole 141b must be formed on one side where the third magnet through-hole is formed.

Of course, each of the first driving magnets 131 to the fourth driving magnets may be seated, placed, or fixed in each of the through holes for the first magnet to the fourth magnet through hole. At this time, similarly, the first driving magnet 131 and the second driving magnet 132 have the same size and shape, and have almost the same lateral length over the entire lateral length of the side of the housing 140. has In addition, the third driving magnet and the fourth driving magnet have the same size and shape, and have a smaller lateral length than the first driving magnet 131 and the second driving magnet 132. can be formed.

Here, preferably, the third magnet through-hole and the fourth magnet through-hole may be symmetrically arranged in a straight line with respect to the center of the housing 140. That is, the third driving magnet 130 and the fourth driving magnet 130 may be symmetrically arranged in a straight line with respect to the center of the housing 140. If the third driving magnet 130 and the fourth driving magnet 130 are disposed opposite to each other while being biased to one side regardless of the center of the housing 140, the coil 120 of the bobbin 110 This is because the electromagnetic force acts biased toward one side, so there is a possibility that the bobbin 110 may be tilted. In other words, the third driving magnet 130 and the fourth driving magnet 130 are arranged symmetrically in a straight line with respect to the center of the housing 140, so that the bobbin 110 and the coil 120 ), an unbiased electromagnetic force can be applied to guide the bobbin 110 to move in the first direction easily and accurately.

Additionally, as shown in FIGS. 3 to 6 and 8, a plurality of first stoppers 143 may be formed to protrude from the upper surface of the housing 140. The first stopper 143 is to prevent collision between the cover member 300 and the body of the housing 140, and when an external impact occurs, the upper surface of the housing 140 is directly pressed against the upper inner surface of the cover member 300. Collisions can be prevented. In addition, the first stopper 143 may also serve to guide the installation position of the upper elastic member 150. For this purpose, as shown in FIG. 9, the first stopper 143 of the upper elastic member 150 A guide groove 155 of a corresponding shape may be formed at a position corresponding to the stopper 143.

Additionally, a plurality of upper frame support protrusions 144 to which the outer frame 152 of the upper elastic member 150 is coupled may be protrudingly formed on the upper side of the housing 140. Meanwhile, as will be described later, a first through hole 152a or a groove of 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, where It may be fixed by adhesive or fusion, and fusion may include heat fusion or ultrasonic fusion.

In addition, as shown in FIG. 7, a plurality of lower frame support protrusions 147 to which the outer frame 162 of the lower elastic member 160 is coupled may be formed to protrude on the lower side of the housing 140. Meanwhile, an insertion groove 162a or a hole of a corresponding shape may be formed in the outer frame 162 of the lower elastic member 160 corresponding to the lower frame support protrusion 147, where adhesive or fusion is used. It can be fixed, and fusion may include thermal fusion or ultrasonic fusion.

The driving magnet 130 may be fixed to the magnet through-hole 141a with adhesive, but this is not limited, and an adhesive member such as double-sided tape may be used. Alternatively, as a modified embodiment, a groove-shaped magnet seating portion may be formed on the inner surface of the housing 140 instead of the magnet through-hole 141a, and the magnet seating portion may be similar to the size and shape of the driving magnet 130. It can be provided with a corresponding size and shape.

The driving magnet 130 may be installed in a position corresponding to the coil 120 provided in the bobbin 110. In addition, the driving magnet 130 may be composed of one body, and in this embodiment, the surface facing the coil 120 of the bobbin 110 can be arranged so that the N pole and the outer surface can be arranged so that the S pole. there is. However, this is not limited, and it is also possible to configure it in the opposite way. Additionally, the driving magnet 130 may be divided into two by a plane perpendicular to the optical axis.

The driving magnet 130 is configured in a rectangular parallelepiped shape with a certain width, and is seated in the magnet through-hole 141a or groove so that the wide surface of the driving magnet 130 is part of the side of the housing 140. can be formed. At this time, the driving magnets 130 facing each other may be installed parallel to each other. Additionally, the driving magnet 130 may be arranged to face the coil 120 of the bobbin 110. At this time, the surfaces of the driving magnet 130 and the coil 120 of the bobbin 110 facing each other may be arranged in a plane plane so that they are parallel to each other. However, this is not limited, and depending on the design, one of the driving magnet 130 and the coil 120 of the bobbin 110 may be flat, and the other may be curved. Alternatively, the facing surfaces of the coil 120 of the bobbin 110 and the driving magnet 130 may all be curved. In this case, the facing surfaces of the coil 120 of the bobbin 110 and the driving magnet 130 may be curved. The curvature of the surface can be formed to be the same.

As described above, one side of the housing 140 is provided with a through hole 141b or a groove for a sensor, and the position sensor 180 is inserted, placed, or seated in the through hole 141b for the sensor, The position sensor 180 is electrically coupled to one surface of the printed circuit board 170 by soldering or soldering. In other words, the printed circuit board 170 may be fixed, supported, or disposed on the outer surface of one of the four sides 141 of the housing where the sensor through hole 141b or groove is provided.

The position sensor 180 may be a displacement detection unit that determines the first displacement value of the bobbin 110 in the first direction together with the sensing magnet 190 of the bobbin 110, which will be described later. To this end, the position sensor 180 and the sensor through hole 141b or groove may be placed at a position corresponding to the position of the sensing magnet 190.

The position sensor 180 may be a sensor that detects changes in magnetic force emitted from the sensing magnet 190 of the bobbin 110. Additionally, the position sensor 180 may be a Hall sensor. However, this is an example, and this embodiment is not limited to the Hall sensor. Any sensor that can detect changes in magnetic force can be used, and any sensor that can detect position in addition to magnetic force is possible, for example For example, a method using a photo reflector, etc. is also possible.

The printed circuit board 170 is coupled to or disposed on one side of the housing 140, and may be provided with a through hole 173 or a groove for mounting as described above. For this reason, the installation position of the printed circuit board 170 can be guided by the mounting protrusion 149 provided on one side of the housing 140.

In addition, the printed circuit board 170 has a plurality of terminals 171 arranged so that external power can be applied to supply current to the coil 120 and the position sensor 180 of the bobbin 110. The number of terminals 171 formed on the printed circuit board 170 may increase or decrease depending on the types of components that require control. Meanwhile, according to this embodiment, the printed circuit board 170 may be prepared as an FPCB.

The printed circuit board 170 may include a control unit that readjusts the amount of current applied to the coil 120 based on the first displacement value detected by the displacement detection unit. That is, the control unit may be configured to control the printed circuit board. It is mounted on (170). In addition, in another embodiment, the control unit may not be mounted on the printed circuit board 170 but on a separate board. This may be a board on which the image sensor of the camera module is mounted, or it may be a separate board. .

The actuator driving distance can be additionally calibrated based on the Hall voltage difference for the change in magnet flux (i.e., magnetic flux density) detected by the Hall sensor.

The bobbin 110 may be configured to reciprocate in the first axis direction with respect to the housing 140 fixed in the first axis direction. An auto-focusing function may be executed due to movement of the bobbin 110 in the first axis direction.

The bobbin 110 may be described in more detail below with reference to the drawings.

Meanwhile, the upper elastic member 150 and the lower elastic member 160 can elastically support the upward and/or downward motion of the bobbin 110 in the optical axis direction. The upper elastic member 150 and the lower elastic member 160 may be provided as leaf springs.

As shown in FIGS. 2 to 4, 9 and 10, the upper elastic member 150 and the lower elastic member 160 are inner frames 151 and 161 and housing 140 coupled to the bobbin 110. ) may include outer frames 152 and 162 coupled to each other and connection portions 153 and 163 connecting the inner frames 151 and 161 and the outer frames 152 and 162.

The connecting portions 153 and 163 may be bent at least once to form a pattern of a certain shape. The bobbin 110 may be elastically (or elastically) supported in its upward and/or downward motion in the first direction of the optical axis through the change in position and slight deformation of the connecting portions 153 and 163.

According to this embodiment, as shown in FIG. 9, the upper elastic member 150 has a plurality of first through holes 152a in the outer frame 152 and a plurality of second through holes 152a in the inner frame 151. (151a) may be provided.

The first through hole 152a is coupled to the upper frame support protrusion 144 provided on the upper surface of the housing 140, and the second through hole 151a or groove is on the upper surface of the bobbin 110, which will be described later. It can be combined with the upper support protrusion provided. That is, the outer frame 152 is fixed and coupled to the housing 140 through the first through hole 152a, and the inner frame 151 is fixed to the bobbin 110 through the second through hole 151a or groove. and may be combined.

The connecting portion 153 may connect the inner frame 151 and the outer frame 152 so that the inner frame 151 is elastically deformable within a predetermined range in a first direction with respect to the outer frame 152. .

At least one of the inner frame 151 and the outer frame 152 of the upper elastic member 150 has a terminal portion electrically connected to at least one of the coil 120 of the bobbin 110 and the printed circuit board 170. It may be provided at least one.

As shown in FIG. 10, the lower elastic member 160 has a plurality of insertion grooves 162a or holes in the outer frame 162 and a plurality of third through holes 161a or holes in the inner frame 161. A groove can be provided.

The insertion groove 162a or hole is coupled to the lower frame support protrusion 147 provided on the lower surface of the housing 140, and the third through hole 161a or groove is the lower surface of the bobbin 110, which will be described later. It can be combined with the lower support protrusion 114 provided in. That is, the outer frame 162 is fixed and coupled to the housing 140 through the insertion groove 162a or a hole, and the inner frame 161 is connected to the bobbin 110 through the third through hole 161a or groove. Can be fixed and combined.

The connecting portion 163 may connect the inner frame 161 and the outer frame 162 so that the inner frame 161 is elastically deformable within a predetermined range in a first direction with respect to the outer frame 162. .

The lower elastic member 160 may include a first lower elastic member 160a and a second lower elastic member 160b that are separated from each other as shown in FIG. 10. Through this two-part structure, the lower elastic member 160 can receive power supplies of different polarities or different power supplies to the first lower elastic member 160a and the second lower elastic member 160b. That is, after the inner frame 161 and the outer frame 162 are coupled to the bobbin 110 and the housing 140, respectively, the inner frame corresponds to both end lines of the coil 120 disposed on the bobbin 110. By providing a solder portion at the position of , power of different polarity or different power sources can be applied by performing a conductive connection such as soldering at the solder portion. In addition, the first lower elastic member is electrically connected to one of the two end wires of the coil, and the second lower elastic member is electrically connected to the other one of the two end wires of the coil to apply a current and/or voltage from the outside. You can receive it.

Meanwhile, the upper elastic member 150 and lower elastic member 160, the bobbin 110, and the housing 140 may be assembled through heat fusion and/or bonding using an adhesive, etc. At this time, the fixing work can be completed by heat fusion fixation according to the assembly sequence and then bonding using adhesive.

As a modified example, the upper elastic member 150 may be configured as a two-part structure, and the lower elastic member 160 may be configured as an integrated structure.

At least one of the inner frame 161 and the outer frame 162 of the lower elastic member 160 has a terminal portion electrically connected to at least one of the coil 120 of the bobbin 110 and the printed circuit board 170. At least one may be provided.

FIG. 11 is a schematic perspective view of the bobbin 110 according to an embodiment of the present embodiment, FIG. 12 is a schematic bottom perspective view of the bobbin 110 according to an embodiment of the present embodiment, and FIG. 13 is a schematic perspective view of the bobbin 110 according to an embodiment of the present embodiment. It is a schematic exploded perspective view of the bobbin 110 according to an embodiment, FIG. 14 is a partially enlarged perspective view of FIG. 13, FIG. 15 is a partially enlarged bottom view of FIG. 13, and FIG. 16 is an accommodation according to an embodiment of the present embodiment. It is a schematic partially enlarged perspective view of the groove 117, and Figure 17 is a schematic longitudinal cross-sectional view of the bobbin 110 according to one embodiment of the present embodiment.

As shown in FIGS. 11 to 17, the bobbin 110 may be installed in the inner space of the housing 140 to be reciprocatable in the direction of the optical axis. A coil 120, which will be described later, is installed on the outer peripheral surface of the bobbin 110 to enable electromagnetic interaction with the driving magnet 130 of the housing 140, so that the coil 120 and the driving magnet 130 are electromagnetic. Due to the miraculous interaction, the bobbin 110 may be reciprocated in the first direction. In addition, the bobbin 110 is elastically (or elastically) supported by the upper elastic member 150 and the lower elastic member 160, and can move in the first direction, which is the optical axis direction, to perform an auto-focusing function. .

Although not shown, the bobbin 110 may include a lens barrel (not shown) in which at least one lens is installed, but the lens barrel is a component of a camera module to be described later and is an essential component of the lens driving device. It may not be an element. The lens barrel can 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. However, this is not limited, and the lens barrel may be directly fixed to the inside of the bobbin 110 using a method other than screwing, without forming a thread on the inner peripheral surface of the bobbin 110. Alternatively, it is also possible for the one or more lenses to be formed integrally with the bobbin 110 without a lens barrel. The lens coupled to the lens barrel may be composed of one piece, or two or more lenses may be configured to form an optical system.

Additionally, a plurality of upper support protrusions 113 and a plurality of lower support protrusions 114 may be formed to protrude from the upper and lower surfaces of the bobbin 110.

As shown in FIG. 11, the upper support protrusion may be provided in a cylindrical or prismatic shape, and may couple and secure the inner frame 151 of the upper elastic member 150 and the bobbin 110. According to this embodiment, a second through hole 151a or a groove may be formed at a position corresponding to the upper support protrusion of the inner frame 151 of the upper elastic member 150. At this time, the upper support protrusion and the second through hole 151a or groove may be fixed by heat fusion or may be fixed with an adhesive member such as epoxy. Additionally, a plurality of upper support protrusions may be provided. At this time, the distance between each upper support protrusion can be appropriately arranged within a range to avoid interference with surrounding components. That is, each of the upper support protrusions may be arranged at regular intervals symmetrically with respect to the center of the bobbin 110, and although their spacing is not constant, they may be symmetrical with respect to a specific imaginary line passing through the center of the bobbin 110. may be formed.

As shown in FIG. 12, the lower support protrusion 114 may be provided in a cylindrical or prismatic shape like the above-mentioned upper support protrusion, and connects the inner frame 161 and the bobbin 110 of the lower elastic member 160. Can be combined and fixed. According to this embodiment, a third through hole 161a or a groove may be formed at a position corresponding to the lower support protrusion 114 of the inner frame 161 of the lower elastic member 160. At this time, the lower support protrusion 114 and the third through hole 161a or groove may be fixed by heat fusion or may be fixed with an adhesive member such as epoxy. Additionally, a plurality of lower support protrusions 114 may be provided as shown in FIG. 12 . At this time, the distance between each lower support protrusion 114 can be appropriately arranged within a range to avoid interference with surrounding components. That is, each lower support protrusion 114 may be arranged symmetrically at regular intervals with respect to the center of the bobbin 110.

And, on the upper and lower surfaces of the bobbin 110, an upper escape groove 112 and a A lower escape groove 118 is formed.

By providing the upper escape groove 112 and the lower escape groove 118, when the bobbin 110 moves in the first direction with respect to the housing 140, the connection portions 153 and 163 and the bobbin 110 By eliminating spatial interference, elastic deformation of the connecting portions 153 and 163 can be more easily performed. Additionally, the location of the upper escape groove may be located at a corner of the housing as in the embodiment, but may also be located on the side depending on the shape and/or location of the connection part of the elastic member.

Additionally, a coil seating groove 116 in which the coil 120 is installed may be provided on the outer peripheral surface of the bobbin 110, but only a seating portion may be provided.

The coil 120 may be provided as a ring-shaped coil block inserted and coupled to the outer peripheral surface of the bobbin 110 or the coil seating groove 116 or seating portion, but this is not limited and the coil 120 The winding may be done directly on the outer peripheral surface of the bobbin 110 or in the coil seating groove 116 or seating portion.

According to this embodiment, the coil 120 may be formed into an approximately octagonal shape as shown in FIG. 13. This corresponds to the shape of the outer peripheral surface of the bobbin 110, and the bobbin 110 may also be provided in an octagonal shape. Additionally, at least four sides of the coil 120 may be straight, and the corners connecting these sides may be round or straight. At this time, the straight portion may be formed to be a surface corresponding to the driving magnet 130. Additionally, the surface of the driving magnet 130 corresponding to the coil 120 may have the same curvature as that of the coil 120. That is, if the coil 120 is straight, the surface of the corresponding driving magnet 130 may be straight, and if the coil 120 is curved, the surface of the corresponding driving magnet 130 may be curved. and may also have the same curvature. Additionally, even if the coil 120 is curved, the surface of the corresponding driving magnet 130 may be straight, or vice versa.

The coil 120 is intended to perform an autofocus function by moving the bobbin 110 in the direction of the optical axis. When current is supplied, electromagnetic force can be formed through electromagnetic interaction with the driving magnet 130. Electromagnetic force can move the bobbin 110.

Meanwhile, the coil 120 may be configured to correspond to the driving magnet 130. As shown, the driving magnet 130 is composed of a single body, so that the entire surface facing the coil 120 has the same polarity. When provided to have, the coil 120 may also be configured so that a surface corresponding to the driving magnet 130 has the same polarity. Meanwhile, although not shown, if the driving magnet 130 is divided into two on a side perpendicular to the optical axis and the side facing the coil 120 is divided into two or more, the coil 120 is also divided into two or more sides. It is also possible to divide the driving magnets 130 into corresponding numbers.

In addition, the bobbin 110 may be provided with a sensing magnet 190 included in the displacement detection unit along with the position detection sensor 180 of the housing 140 described above. The sensing magnet 190 may be fixed, placed, or coupled to the bobbin 110. Because of this, the sensing magnet 190 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. Additionally, the sensing magnet 190 may be composed of one body, and may be arranged so that the upper direction of the bobbin 110 is the N pole and the lower direction of the bobbin 110 is the S pole. However, this is not limited, and it is also possible to configure it in the opposite way. Additionally, the sensing magnet 190 may be divided into two by a plane perpendicular to the optical axis.

Here, as shown in FIGS. 13 to 17, the bobbin 110 may be provided with a receiving groove 117 for receiving the sensing magnet 190 on the outer peripheral surface of the bobbin 110.

The receiving groove 117 may be formed from the outer surface of the bobbin 110 to the inside of the bobbin 110 at a predetermined depth.

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 coil 120. In addition, at least a portion of the receiving groove 117 may be formed to be concave at a predetermined depth further inside the bobbin 110 than the coil seating groove 116. In this way, by forming the receiving groove 117 in the inner direction of the bobbin 110, the sensing magnet 190 can be accommodated inside the bobbin 110, and as a result, a separate device for the sensing magnet 190 is required. Since there is no need to secure 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 position sensor 180 of the housing 140 (or a position opposite to the position sensor 180). Due to this, the distance between the sensing magnet 190 and the position detection sensor 180 is the thickness of the coil 120 and the separation distance between the coil 120 and the position detection sensor 180, or the coil and the position detection sensor here. Since the distance between them can be further included and minimized to that distance, the magnetic force detection accuracy of the position detection sensor 180 can be improved.

The receiving groove 117 may have an opening 119 communicating with the receiving groove 117 on one of the lower and upper surfaces of the bobbin 110. For example, as shown in FIG. 17, the receiving groove 117 is formed by opening a portion of the lower surface of the bobbin 110 to form an opening 119, and the opening 119 is formed by the receiving groove 117. can form an entrance. The sensing magnet 190 can be inserted, placed, or fixed through the opening 119, and can be separated through this.

More specifically, as shown in FIGS. 15 to 17, the receiving groove 117 has an inner surface on which one surface of the sensing magnet 190 is supported, and a predetermined distance from the inner surface so that adhesive can be injected. It may include an adhesive groove 117b that is concavely formed deeper inward.

The inner surface is a surface located in the inner direction toward the center of the bobbin 110, and when the sensing magnet 190 has a rectangular parallelepiped shape, the wide surface of the sensing magnet 190 is contacted or seated. am.

The adhesive groove 117b may be a groove in which a portion of the inner surface is formed to be more deeply concave in an inward direction toward the center of the bobbin 110. The adhesive groove 117b may preferably be formed from the opening 119 to one inner surface of the bobbin 110 where one surface of the sensing magnet 190 is contacted, seated, or disposed.

As shown in FIG. 17, the adhesive groove 117b may further include a first additional groove 117c formed longer than the length of the sensing magnet 190 in the vertical thickness direction of the bobbin 110. You can. That is, the first additional groove 117c is an extension of the adhesive groove 117b that is concave deeper than the inner surface of the bobbin 110 on which the back surface of the sensing magnet 190 is contacted, seated, or disposed. am. By providing the first additional groove (117c), when the adhesive is injected into the adhesive groove (117b) through the opening 119, the adhesive is filled from the first additional groove (117c) to fill the inside of the adhesive groove (117b). Since the filling prevents the adhesive from overflowing in the adhesive groove (117b) and flowing to the coil 120 along the gap between the sensing magnet 190 and the receiving groove 117, the sensing magnet 190 ) can reduce the incidence of defects in the lens driving device 100 during the coupling process.

In addition, the adhesive groove 117b may further include a second additional groove 117a formed at a predetermined depth in an inward direction from the opening 119 toward the center of the bobbin 110. That is, the second additional groove 117a may be formed deeper in the inner direction toward the center of the bobbin 110 than the inner surface near the opening 119. The second additional groove 117a is in communication with the adhesive groove 117b. In other words, the second additional groove 117a is an extension of the adhesive groove 117b. In this way, by providing the second additional groove (117a), the adhesive can be injected into the adhesive groove (117b) through the second additional groove (117a), so that the adhesive overflows near the opening (119) and forms a coil ( 120), etc., adhesion to other components of the bobbin 110 can be prevented, thereby reducing the incidence of defects in the lens driving device 100 during the coupling process of the sensing magnet 190.

Additionally, as a modified example, the second additional groove 117a may be provided alone in the bobbin 110 without the adhesive groove 117b. In this case, the bobbin 110 and the sensing magnet 190 can be coupled and fixed by injecting adhesive into the second additional groove 117a.

Preferably, the adhesive groove 117b may include at least one of the first additional groove 117c and the second additional groove 117a. That is, the adhesive groove 117b may include only the first additional groove 117c or only the second additional groove 117a.

As a modified embodiment, the receiving groove has a depth between the inner surface on which one surface (i.e., the wide surface) of the sensing magnet is supported and the outer peripheral surface (i.e., the coil seating groove surface) on which the coil is provided. It may be less than the thickness of the magnet. Because of this, the sensing magnet can be fixed in the receiving groove by the inner pressing force of the coil due to winding of the coil. In this case, there is no need to use adhesive.

As an additional embodiment, although not shown in the drawings, the bobbin 110 is symmetrical with the receiving groove 117 with respect to the center of the bobbin 110 on the outer peripheral surface facing the outer peripheral surface where the receiving groove 117 is formed. It may further include an additional receiving groove 117 formed on the outer peripheral surface of the bobbin 110 at the position provided, and a weight balance member accommodated in the additional receiving groove 117.

That is, the additional receiving groove 117 is a bobbin with a predetermined depth at a position symmetrical to the receiving groove 117 in a straight line with respect to the center of the bobbin 110 on the outer peripheral surface facing the outer peripheral surface where the receiving groove 117 is formed. It may be formed in the inner direction of (110). Additionally, the weight balance member is fixed and coupled to the additional receiving groove 117 and has the same weight as the magnetic force sensing member.

In this way, by providing the additional receiving groove 117 and the weight balancing member, the horizontal weight imbalance of the bobbin 110 due to the provision of the receiving groove 117 and the sensing magnet 190 is reduced by the installation of the weight balancing member. Compensation is possible.

Preferably, the additional receiving groove 117 may include at least one of the adhesive groove 117b, the first additional groove 117c, and the second additional groove 117a.

According to the above, the present embodiment can shorten the focus alignment time of the lens by feedbacking the amount of displacement of the lens in the optical axis direction and readjusting the position of the lens in the optical axis direction.

In addition, this embodiment can minimize the gap between the sensing magnet provided in the bobbin, which is a moving body, and the position detection sensor provided in the housing, which is fixed, and this allows more accurate detection of the amount of displacement in the direction of the optical axis of the lens. It can be positioned more accurately at the focal length of the lens.

In addition, in this embodiment, by providing a sensing magnet inside the bobbin and a position detection sensor inside the housing, no separate space is required for mounting the displacement detection unit, thereby improving space efficiency of the camera module (especially the bobbin). It can be improved.

In addition, a camera module can be configured by combining a lens with the lens driving device of this embodiment and further including an image sensor and a printed circuit board with the image sensor disposed at the bottom, and the base of the lens driving device and the image sensor are It can be combined with an arranged printed circuit board.

In addition, the camera module may further include a camera module control unit, and compare the first displacement value calculated based on the current change value detected by the displacement detection unit and the focal length of the lens according to the distance between the subject and the lens. You can. Thereafter, the camera module control unit readjusts the amount of current applied to the coil 120 of the bobbin 110 when the first displacement value or the current position of the lens and the focal length of the lens do not correspond to the bobbin 110. may be moved in the first direction by a second displacement amount. In addition, the displacement detection unit detects the position sensor 180, which is fixedly coupled to the housing 140, which is a fixed body, according to the movement in the first direction of the sensing magnet 190, which is fixedly coupled to the bobbin 110, which is a moving body. By detecting the change in magnetic force emitted from the magnet 190, a separate driver IC or the camera module control unit detects the current position or first displacement amount of the bobbin 110 based on the amount of current change output based on the change in the detected magnetic force. can be calculated or judged. The current position or first displacement amount of the bobbin 110 calculated or determined by the displacement detection unit is transmitted to the control unit of the printed circuit board 170, and the control unit re-determines the position of the bobbin 110 for auto focusing and coils ( 120) can be adjusted.

In the above, a specific embodiment has been shown and described to illustrate the technical idea of the present embodiment, but the present embodiment is not limited to the same configuration and operation as the specific embodiment as described above, and various modifications may be made without departing from the scope of the present embodiment. It can be carried out within. Accordingly, such modifications should also be considered as falling within the scope of this embodiment, and the scope of this embodiment may be determined by the claims described later.

100: Lens driving device
110: Bobbin
120: coil
130: Driving magnet
140: housing
150: upper elastic member
160: lower elastic member
170: printed circuit board
180: Position detection sensor
190: Magnet for sensing
210: base
300: Cover member

Claims (20)

cover;
a bobbin disposed within the cover;
a coil disposed on the bobbin;
a first magnet disposed between the cover and the bobbin; and
It includes a second magnet disposed on the bobbin,
The second magnet is disposed between the bobbin and the coil,
The second magnet overlaps a portion of the coil in a first direction perpendicular to the optical axis,
Comprising a circuit board facing the coil and coupled to a position detection sensor,
The coil is a lens driving device disposed between the second magnet and the circuit board in the first direction. According to paragraph 1,
The cover includes a first side plate, a second side plate overlapping the first side plate in a second direction perpendicular to the optical axis, a third side plate, and a fourth side plate overlapping the third side plate in the first direction,
The first magnet includes a first driving magnet disposed between the bobbin and the first side plate of the cover and a second driving magnet disposed between the bobbin and the second side plate of the cover. According to paragraph 2,
A lens driving device in which the first magnet is not disposed between the bobbin and the third side plate. According to paragraph 2,
The second magnet is a lens driving device disposed between the bobbin and the third side plate. According to paragraph 1,
The second magnet is a lens driving device disposed in a receiving groove formed on the outer surface of the bobbin. According to clause 5,
A lens driving device wherein a portion of the receiving groove of the bobbin overlaps the coil in the first direction. According to clause 5,
A lens driving device wherein the receiving groove of the bobbin includes an opening that opens in the direction of the optical axis. According to clause 5,
The bobbin is a lens driving device including an additional receiving groove on the outer surface of the bobbin at a position opposite to the receiving groove. According to clause 8,
A lens driving device including a weight balance member disposed in the additional receiving groove. According to paragraph 1,
The second magnet is a lens driving device disposed in an area adjacent to a corner of the bobbin rather than the center of the outer surface of the bobbin. According to paragraph 1,
The circuit board is a lens driving device disposed between the second magnet and the cover. According to paragraph 1,
Includes a base coupled to the cover,
The circuit board includes a plurality of terminals connected to an external power source,
A lens driving device wherein the plurality of terminals are disposed on one side of the base. printed circuit board;
an image sensor disposed on the printed circuit board;
The lens driving device of claim 1 disposed on the printed circuit board; and
A camera including a lens coupled to the bobbin of the lens driving device. A mobile phone containing the camera of claim 13. housing;
a bobbin disposed within the housing;
a coil disposed on the bobbin;
A first magnet disposed in the housing;
a second magnet disposed on the bobbin; and
It includes a sensor arranged to overlap the second magnet in a first direction perpendicular to the optical axis,
The second magnet is disposed between the bobbin and the coil,
At least a portion of the sensor overlaps the second magnet and the coil in the first direction,
Comprising a circuit board facing the coil and on which a position detection sensor is disposed,
A lens driving device wherein the coil is disposed between the second magnet and the circuit board. According to clause 15,
The second magnet is a lens driving device disposed in a receiving groove formed on the outer surface of the bobbin. According to clause 16,
A lens driving device wherein a portion of the receiving groove of the bobbin overlaps the coil in the first direction. Base;
a cover coupled to the base;
a bobbin disposed within the cover;
a coil disposed on the bobbin;
a first magnet disposed between the cover and the bobbin;
a second magnet disposed on the bobbin;
a circuit board disposed between the second magnet and the cover; and
Including a sensor disposed on the circuit board,
The second magnet is disposed between the bobbin and the coil,
At least a portion of the second magnet overlaps the coil, the sensor, and the circuit board in a first direction perpendicular to the optical axis,
The second magnet does not overlap the first magnet in the first direction,
A lens driving device wherein the coil is disposed between the second magnet and the circuit board. According to clause 18,
The second magnet is a lens driving device disposed in an area adjacent to a corner of the bobbin rather than the center of the outer surface of the bobbin. delete