KR102508491B1 - Lens driving unit and camera module including the same - Google Patents

Abstract

One embodiment of the lens driving device, the bobbin in which the first coil is installed on the outer peripheral surface; a position sensor provided on the bobbin; a first magnet provided to face the first coil and the position sensor; a housing supporting the first magnet; and a conductive pattern formed by being plated on the bobbin and electrically connected to the position sensor.

Description

Lens driving unit and camera module including the same {Lens driving unit and camera module including the same}

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

The contents described in this part simply provide background information on the embodiments and do not constitute prior art.

In recent years, the development of IT products such as mobile phones, smart phones, tablet PCs, and laptops with built-in micro digital cameras has been actively conducted.

In the case of an IT product with a built-in compact digital camera, a lens driving device that performs auto focusing to align the focal length of a lens by adjusting the distance between an image sensor that converts external light into a digital image or a digital image and a lens is used. It is built in.

Auto focusing is performed by measuring the displacement value in the optical axis direction, that is, in the first direction, by the optical axis direction displacement detecting unit provided in the lens driving device, and adjusting the distance between the image sensor and the lens by the control unit based on the measured displacement value. It can be.

On the other hand, if a means for auto focusing is provided in the lens driving device, the lens driving device may be complicated by this means or may cause interference with other parts provided in the lens driving device.

Accordingly, the embodiment may provide a lens driving device provided with a means for auto focusing having a simple structure and significantly reducing interference with other parts, and a camera module including the same.

The technical problem to be achieved by the embodiment is not limited to the technical problem mentioned above, and other technical problems not mentioned will be clearly understood by those skilled in the art from the description below.

One embodiment of the lens driving device, the bobbin in which the first coil is installed on the outer peripheral surface; a position sensor provided on the bobbin; a first magnet provided to face the first coil and the position sensor; a housing supporting the first magnet; and a conductive pattern formed by being plated on the bobbin and electrically connected to the position sensor.

The conduction pattern may be formed on the surface of the bobbin by a laser direct structuring (LDS) method.

A seating groove in which the position sensor is seated may be formed on the bobbin, and one end of the conduction pattern electrically connected to the position sensor may be formed in the seating groove.

An embodiment of the lens driving device may further include upper and lower elastic members coupled to the bobbin and the housing, and the other end of the conduction pattern may be electrically connected to the upper elastic member.

A plurality of the conductive patterns may be provided, and the upper elastic member may be provided by being divided into at least the same number as the number of the conductive patterns.

The conductive patterns may be provided in four, the upper elastic member may be divided into six, and the four conductive patterns may be electrically connected to four of the divided six portions of the upper elastic member.

The position sensor may be provided to be spaced apart from the first coil in a first direction on the bobbin.

The first magnet and the position sensor may be spaced apart from each other on surfaces facing each other.

The separation distance between the first magnet and the position sensor may be 0.05 mm to 0.3 mm.

The N pole and the S pole of the first magnet may be disposed in a second direction or a third direction perpendicular to the first direction.

A plurality of first magnets may be provided in a first direction, and N poles and S poles of each of the first magnets may be disposed in a second direction or a third direction perpendicular to the first direction.

The plurality of first magnets may be disposed to have different polarities in a first direction.

The center of the position sensor may be provided so as not to deviate 0.5 mm from an upper end or a lower end of the first magnet.

An adhesive may be applied to a surface of the bobbin and an upper surface of the conductive pattern to at least a part of a portion where the conductive pattern is formed on the bobbin.

Another embodiment of the lens driving device, the bobbin in which the first coil is installed on the outer peripheral surface; a position sensor provided on the bobbin; a first magnet provided to face the first coil and the position sensor; a housing supporting the first magnet; upper and lower elastic members coupled to the bobbin and the housing; and a conductive pattern formed by being plated on the bobbin and electrically connected to the position sensor.

One end of the conduction pattern may be electrically connected to the position sensor, and the other end of the conduction pattern may be electrically connected to the upper elastic member.

The conductive pattern may be formed by bonding nickel to a surface of the bobbin and plating gold on an upper surface of the nickel.

One embodiment of the camera module, the lens driving device; and an image sensor mounted on the lens driving device.

In the embodiment, the structure of the lens driving device can be simplified by electrically connecting the position sensor provided on the bobbin and the upper elastic member using a conduction pattern formed on the surface of the bobbin.

In addition, by using the conduction pattern formed on the surface of the bobbin, there is an effect of significantly reducing interference between each part constituting the lens driving device compared to the case of using a separate structure for electrical connection or a conducting member.

1 is a perspective view illustrating a lens driving device according to an exemplary embodiment.
2 is an exploded perspective view illustrating a lens driving device according to an exemplary embodiment.
Figure 3a is a side view showing a bobbin according to an embodiment.
FIG. 3B is a side view showing a state in which the first magnet is disposed in FIG. 3A.
Figure 4 is a view showing a state in which the position sensor according to an embodiment is removed from Figure 3a.
5 is a perspective view showing some components of a lens driving device according to an exemplary embodiment.
6A is a plan view of FIG. 5 .
FIG. 6B is a plan view in which some components of FIG. 6A are removed.
7 is a view showing the arrangement of a first magnet and a position sensor according to an embodiment.
8 is a view showing the arrangement of a first magnet and a position sensor according to another embodiment.
9 is a graph showing the relationship between the magnetic flux of the first magnet and the moving distance of the bobbin in the first direction.
10 is a graph showing test results of driving characteristics of a lens driving device according to an exemplary embodiment.

Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Embodiments can apply various changes and can have various forms, and specific embodiments will be illustrated in the drawings and described in detail in the text. However, this is not intended to limit the embodiments to a specific form disclosed, and should be understood to include all modifications, equivalents, or substitutes included in the spirit and technical scope of the embodiments. In this process, the size or shape of the components shown in the drawings may be exaggerated for clarity and convenience of explanation.

Terms such as "first" and "second" may be used to describe various components, but the components should not be limited by the terms. These terms are only used for the purpose of distinguishing one component from another. In addition, terms specifically defined in consideration of the configuration and operation of the embodiment are only for describing the embodiment, and do not limit the scope of the embodiment.

In the description of the embodiment, in the case where it is described as being formed on "upper (above)" or "lower (on or under)" of each element, on or under (on or under) ) includes both elements formed by directly contacting each other or by indirectly placing one or more other elements between the two elements. In addition, when expressed as “up (up)” or “down (down) (on or under)”, it may include the meaning of not only the upward direction but also the downward direction based on one element.

In addition, relational terms such as "upper/upper/upper" and "lower/lower/lower" used below do not necessarily require or imply any physical or logical relationship or order between such entities or elements, It may be used only to distinguish one entity or element from another entity or element.

In addition, an orthogonal coordinate system (x, y, z) can be used in the drawing. In the drawing, the x-axis and the y-axis mean axes perpendicular to the optical axis, and for convenience, the optical axis direction (z-axis direction) may be referred to as a first direction, an x-axis direction as a second direction, and a y-axis direction as a third direction.

1 is a perspective view illustrating a lens driving device according to an exemplary embodiment. 2 is an exploded perspective view illustrating a lens driving device according to an exemplary embodiment.

An image stabilization device applied to a small camera module of a mobile device such as a smartphone or tablet PC is designed to prevent the outline of a captured image from being formed clearly due to vibration caused by the user's hand shake when capturing a still image. means a configured device.

In addition, the auto focusing device is a device that automatically focuses an image of a subject on an image sensor surface. Such an image stabilization device and an auto-focusing device can be configured in various ways. In the case of an embodiment, an optical module composed of a plurality of lenses is moved in a first direction or moved on a plane perpendicular to the first direction to prevent such hand shake. A correction operation and/or an auto focusing operation may be performed.

As shown in FIGS. 1 and 2 , the lens driving device according to the embodiment may include a movable part. At this time, the movable unit may perform functions of auto focusing of the lens and hand shake correction. The movable unit may include the bobbin 110, the first coil 120, the first magnet 130, the housing 140, the upper elastic member 150, the lower elastic member 160, and the position sensor 170. there is.

The bobbin 110 is provided inside the housing 300 and has a first coil 120 disposed inside the first magnet 130 on an outer circumferential surface, and the first magnet 130 and the first coil It may be installed to be reciprocally movable in the first direction in the inner space of the housing 140 by electromagnetic interaction between the 120 .

A first coil 120 is installed on the outer circumferential surface of the bobbin 110 to enable electromagnetic interaction with the first magnet 130 . At this time, the first magnet 130 may be provided to face the first coil 120 and a position sensor 170 to be described later for electromagnetic interaction.

In addition, the bobbin 110 is elastically supported by the upper and lower elastic members 150 and 160 and moves in a first direction to perform an auto focusing function.

The bobbin 110 may include a lens barrel (not shown) in which at least one lens is installed. The lens barrel can be coupled to the inside of the bobbin 110 in various ways.

For example, a female screw thread may be formed on an inner circumferential surface of the bobbin 110 and a male screw thread corresponding to the screw thread may be formed on an outer circumferential surface of the lens barrel, and the lens barrel may be coupled to the bobbin 110 by screwing of the female screw thread. 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 screw coupling without forming a thread on the inner circumferential surface of the bobbin 110 .

Alternatively, the one or more lenses may be integrally formed with the bobbin 110 without a lens barrel. However, in the embodiment, a lens driving device having a separate lens barrel will be described.

The lens coupled to the lens barrel may be composed of one sheet, or two or more lenses may form an optical system.

The auto focusing function is controlled according to the direction of the current, and the auto focusing function may be implemented by moving the bobbin 110 in the first direction. For example, when a forward current is applied, the bobbin 110 may move upward from an initial position, and when a reverse current is applied, the bobbin 110 may move downward from an initial position. Alternatively, the moving distance in one direction from the initial position may be increased or decreased by adjusting the amount of one-way current.

A plurality of upper support protrusions and lower support protrusions may protrude from the upper and lower surfaces of the bobbin 110 . The upper support protrusion may be provided in a cylindrical shape or a prismatic shape, and may couple and fix the upper elastic member 150 . The lower support protrusion may be provided in a cylindrical shape or a prismatic shape like the upper support protrusion described above, and may couple and fix the lower elastic member 160 .

In this case, a through hole corresponding to the upper support protrusion may be formed in the upper elastic member 150 , and a through hole corresponding to the lower support protrusion may be formed in the lower elastic member 160 . Each of the support protrusions and the through hole may be fixedly coupled by thermal fusion or an adhesive member such as epoxy.

The housing 140 may have a hollow pillar shape supporting the first magnet 130 and may be formed in a substantially rectangular shape. The first magnet 130 and the support member 220 may be coupled to each other and disposed on the side surface of the housing 140 . In addition, as described above, the bobbin 110 guided by the housing 140 and moving in the first direction may be disposed on the inner circumferential surface of the housing 140 .

The upper elastic member 150 and the lower elastic member 160 are coupled to the housing 140 and the bobbin 110, and the upper elastic member 150 and the lower elastic member 160 are the first part of the bobbin 110. upward and/or downward motion in the direction can be supported elastically. The upper elastic member 150 and the lower elastic member 160 may be provided as leaf springs.

As shown in FIG. 2 , the upper elastic member 150 may be provided in a plurality separated from each other. Through this multi-division structure, each divided part of the upper elastic member 150 may receive currents of different polarities or different power sources. In addition, the lower elastic member 160 may also have a multi-division structure and be electrically connected to the upper elastic member 150 .

Meanwhile, the upper elastic member 150, the lower elastic member 160, the bobbin 110, and the housing 140 may be assembled through thermal fusion and/or bonding using an adhesive.

The position sensor 170 is coupled to the bobbin 110 and may move together with the bobbin 110 . The position sensor 170 may detect the vertical displacement of the bobbin 110 in the first direction and output the detected result as a feedback signal, that is, an electrical signal.

The vertical displacement of the bobbin 110 in the first direction may be adjusted using a result of detecting the vertical displacement of the bobbin 110 in the first direction using the feedback signal.

The position detection sensor 170 may be a sensor that detects a change in magnetic force emitted from the first magnet 130 . Also, the position sensor 170 may be a Hall sensor.

However, this is an example, and in this embodiment, the position sensor 170 is not limited to the hall sensor, and any sensor capable of detecting a change in magnetic force can be used, and any sensor capable of detecting a position other than magnetic force can be used. Any one is possible, and for example, a method using a photo reflector or the like is also possible.

The position sensor 170 may be coupled to the bobbin 110 or the housing 140 in various forms, and depending on the type in which the position sensor 170 is coupled, the position sensor 170 applies current in various ways. can receive In the embodiment, a state in which the position sensor 170 is coupled to the bobbin 110 is shown, and the specific structure of the lens driving device according to the embodiment will be described below based on this embodiment.

Meanwhile, a separate sensing magnet (not shown) facing the position sensor 170 may be provided in the lens driving device, or the first driving magnet 130 may be used. At this time, while the bobbin 110 moves up and down in the first direction, the position sensor 170 detects a change in the magnetic force of the sensing magnet or the first magnet 130 to determine the direction of the bobbin 110 in the first direction. Up and down displacement can be detected.

In the embodiment, the position sensor 170 is provided with a structure for detecting a change in magnetic force of the first magnet 130 . Hereinafter, the specific structure of the lens driving device of the embodiment will be described based on these embodiments.

The base 210 is disposed below the bobbin 110, may be provided in a substantially rectangular shape, and the printed circuit board 250 may be seated thereon.

A support groove having a corresponding size may be formed on a surface of the base 210 facing the portion where the terminal surface 253 of the printed circuit board 250 is formed. This support groove is formed concavely inward from the outer circumferential surface of the base 210 to a certain depth, so that the portion where the terminal surface 253 is formed does not protrude outward or the amount of protrusion can be adjusted.

The support member 220 is disposed on the side of the housing 140, has an upper side coupled to the housing 140 and a lower side coupled to the base 210, and the bobbin 110 and the housing 140 are It can be supported to be movable in the second and third directions perpendicular to the first direction, and can also be electrically connected to the first coil 120 .

Since each support member 220 according to the embodiment is disposed on the outer surface of the corner of the housing 140, a total of four may be installed symmetrically with each other. Also, the support member 220 may be electrically connected to the upper elastic member 150 . That is, for example, the support member 220 may be electrically connected to a portion of the upper elastic member 150 where the through hole is formed.

In addition, since the support member 220 is formed as a separate member from the upper elastic member 150, the support member 220 and the upper elastic member 150 may be electrically connected through conductive adhesive or solder. Accordingly, the upper elastic member 150 may apply current to the first coil 120 through the electrically connected support member 220 .

Meanwhile, in FIG. 2 , the linear support member 220 is illustrated as an embodiment, but is not limited thereto. That is, the support member 220 may be provided in the form of a plate-shaped member or the like.

The second coil 230 may perform hand shake correction by moving the housing 140 in the second and/or third directions through electromagnetic interaction with the first magnet 130 .

Here, the second and third directions may include directions substantially close to the x-axis and y-axis directions as well as the x-axis and y-axis directions. That is, when viewed from the driving side of the embodiment, the housing 140 may move parallel to the x-axis and y-axis, but may also move slightly inclined to the x-axis and y-axis when moving while being supported by the support member 220 there is.

Therefore, the first magnet 130 needs to be installed at a position corresponding to the second coil 230 .

The second coil 230 may be disposed to face the first magnet 130 fixed to the housing 140 . In one embodiment, the second coil 230 may be disposed outside the first magnet 130 . Alternatively, the second coil 230 may be installed on the lower side of the first magnet 130 at a predetermined distance apart.

According to the embodiment, a total of four second coils 230 may be installed on the four sides of the circuit member 231, but is not limited thereto, one for the second direction and one for the third direction. It is possible that only two such as dogs are installed, and four or more may be installed.

In the case of the embodiment, a circuit pattern is formed on the circuit member 231 in the shape of the second coil 230, and an additional second coil may be disposed above the circuit member 231, but is not limited thereto, and the circuit pattern is not limited thereto. Without forming a circuit pattern in the shape of the second coil 230 on the member 231 , only a separate second coil 230 may be disposed above the circuit member 231 .

Alternatively, it is also possible to configure the second coil 230 by winding a wire in a donut shape or to form the second coil 230 in an FP coil shape and electrically connect it to the printed circuit board 250.

The circuit member 231 including the second coil 230 may be installed on an upper surface of the printed circuit board 250 disposed above the base 210 . However, it is not limited thereto, and the second coil 230 may be disposed in close contact with the base 210 or may be disposed apart from each other by a certain distance, and may be formed on a separate substrate to attach the substrate to the printed circuit board 250. Stacked connections are also possible.

The printed circuit board 250 is electrically connected to at least one of the upper elastic member 150 and the lower elastic member 160 and coupled to the upper surface of the base 210, and as shown in FIG. 2, the A through hole into which the support member 220 is inserted may be formed at a position corresponding to an end of the support member 220 .

A bent terminal surface 253 on which the terminal 251 is installed may be formed on the printed circuit board 250 . A plurality of terminals 251 are disposed on the terminal surface 253 to receive external power and supply current to the first coil 120 and the second coil 230 . The number of terminals formed on the terminal surface 253 may be increased or decreased according to the types of components that need to be controlled. Also, the printed circuit board 250 may include one or more than three terminal surfaces 253 .

The cover member 300 may be provided in a substantially box shape, accommodate the movable part, the second coil 230, and a part of the printed circuit board 250, and may be combined with the base 210. The cover member 300 protects the movable part, the second coil 230, the printed circuit board 250, etc. accommodated therein from being damaged, and in particular, the first magnet 130, the The leakage of the electromagnetic field generated by the first coil 120, the second coil 230, etc. to the outside can be limited so that the electromagnetic field can be focused.

Figure 3a is a side view showing the bobbin 110 according to an embodiment. FIG. 3B is a side view showing a state in which the first magnet 130 is disposed in FIG. 3A. 4 is a view showing a state in which the position sensor 170 according to an embodiment is removed in FIG. 3A.

The position sensor 170 may be coupled to the bobbin 110 and provided. For example, a seating groove 111 in which the position sensor 170 is seated is formed in the bobbin 110, and as shown in FIG. 4, the seating groove 111 has the position sensor 170 ) and one end 410 of the conductive pattern (conductive pattern, 400) or surface electrode or surface circuit or surface circuit pattern or plating line electrically connected to the surface may be formed.

Referring to FIG. 5 , the seating groove 111 may be formed by, for example, a portion of the bobbin 110 being recessed at a position where the position sensor 170 is coupled to the bobbin 110 . Since the seating groove 111 is formed in a recessed shape in the bobbin 110, the position sensor 170 seated in the seating groove 111 and coupled to the bobbin 110 has the bobbin 110 first Interference with other parts of the lens driving device can be avoided even if it moves vertically in the direction.

The position sensor 170 may be coupled to the bobbin 110 by being soldered with the conduction pattern 400 or the surface electrode or surface circuit or surface circuit pattern or one end 410 of the plating line. Alternatively, the position sensor 170 may be combined with the bobbin 110 by an adhesive such as epoxy. Alternatively, the position sensor 170 is soldered to one end 410 of the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line, and at the same time is attached to the seating groove 111 by an adhesive such as epoxy. It may be bonded and firmly coupled to the bobbin 110.

Meanwhile, as shown in FIGS. 3A and 3B , the position sensor 170 may be spaced apart from the first coil 120 in a first direction from the bobbin 110 . Since an electric field or a magnetic field may be formed in the first coil 120 to which current is applied, the position sensor 170 is moved by the first magnet 130 by the electric field or magnetic field formed in the first coil 120. ) can detect changes in the magnetic field.

Therefore, in order to prevent erroneous detection of the position sensor 170, it is appropriate that the first coil 120 and the position sensor 170 are provided on the bobbin 110 so as to be spaced apart from each other by a predetermined distance in the first direction. do.

In the embodiment, as shown in FIGS. 3A, 3B and 4 , the bobbin 110 may be provided with a conductive pattern 400 or a surface electrode or a surface circuit or a surface circuit pattern or a plating line. The conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line is plated on the surface of the bobbin 110 and may be electrically connected to the position sensor 170 .

The conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line may be formed on the surface of the bobbin 110 by a laser direct structuring (LDS) method, for example. LDS refers to a laser processing method that uses a laser to form circuit patterns and wires on the surface of an object. The LDS process may proceed as follows, for example.

First, the bobbin 110 may be irradiated with a laser to form a conductive pattern 400, a surface electrode, a surface circuit, a surface circuit pattern, or a pattern of a plating line. At this time, the bobbin 110 on which the conductive pattern 400 or the surface electrode or the surface circuit or the surface circuit pattern or the plating line is formed may be formed of a thermoplastic resin material, for example, formed of a liquid crystal polymer (LCP) material. It can be. A portion of the bobbin 110 to which the laser is irradiated may be partially melted. The portion melted by the laser may have a surface roughness sufficient for plating.

Next, a primary plating operation using a primary metal may be performed on the pattern formed by the laser. At this time, the primary metal used in the primary plating operation may be, for example, nickel or copper having good electrical conductivity.

Next, in the pattern where the primary metal is plated, a secondary plating operation using a secondary metal may be performed on the upper surface of the primary metal. At this time, the secondary metal used in the secondary plating operation may be, for example, gold having good electrical conductivity and strong corrosion resistance and chemical resistance.

On the other hand, the primary or secondary metal used in the plating operation is not limited to the above embodiment, and any material can be used as long as it is electrically conductive and suitable for plating.

On the other hand, the conductive pattern 400, surface electrode, surface circuit, surface circuit pattern, or one end 410 of a plating line electrically connected to the position sensor 170 may be formed in the seating groove 111, The other end of the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line may be electrically connected to the upper elastic member 150 . An embodiment of the electrical connection structure between the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line and the upper elastic member 150 will be described in detail below with reference to FIGS. 5, 6A and 6B. .

On the other hand, as shown in FIG. 4, in the embodiment, the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line is provided in plurality, and each conductive pattern 400 or surface electrode or surface circuit is provided in plurality. Circuits or surface circuit patterns or plating lines may be electrically connected to the position sensor 170, respectively.

In the embodiment, four conductive patterns 400 or surface electrodes or surface circuits or surface circuit patterns or plating lines are formed on the bobbin 110, and each conductive pattern 400 or surface electrodes or surface circuits or surface circuit patterns or plating Lines may be electrically connected to the position sensor 170 .

This is because the position sensor 170 has a structure including two input terminals and two output terminals. Therefore, the number of conductive patterns 400 or surface electrodes or surface circuits or surface circuit patterns or plating lines can be adjusted according to the number of input terminals and output terminals of the position sensor 170. The number of conductive patterns 400 or surface electrodes or surface circuits or surface circuit patterns or plating lines may be the same as the sum of input terminals and output terminals of the position sensor 170 .

The position sensor 170 may use, for example, a Hall sensor or an MR sensor. It is appropriate that the position sensor 170 is seated on the bobbin 110, and may be seated on the bobbin 110 in a horizontal or vertical direction.

It is appropriate for the position sensor 170 to be seated at a position on the bobbin capable of measuring the electromagnetic force value of the first magnet 130 for both sensing and driving, and to partially overlap the first magnet 130. can be located.

The location of the position detection sensor 170 is positioned so as to face the central portion of the first magnet 130, or is positioned so as to face the central portion 130 of the first magnet at a position biased to one side, so that the design space of the bobbin can be secured. It is possible to make the bobbin 110 have an appropriate thickness. Due to the arrangement of the position sensor 170, the reliability of the bobbin 110, the position sensor 170, etc. can be secured, and injection molding of the bobbin 110 can be facilitated.

On the other hand, the first coil 120 is arranged to be biased to the upper or lower side of the bobbin 110 in order to suppress the sensing characteristic defect due to the high frequency of the position sensor 170, or the position sensor 170 It can be placed on the upper surface of the position detection sensor 170 to protect the soldering area.

If the position sensor 170 and the driving driver are integrally formed, the conduction pattern 400 may be directly electrically connected to the integrated circuit (IC) of the driving driver.

5 is a perspective view showing some components of a lens driving device according to an exemplary embodiment. 6A is a plan view of FIG. 5 . FIG. 6B is a plan view in which some components of FIG. 6A are removed.

The conductive pattern 400 or the surface electrode or the surface circuit or the surface circuit pattern or the plating line may be provided in plurality, and accordingly, the upper elastic member 150 may include the conductive pattern 400 or the surface electrode or the surface circuit or It may be provided by being divided into at least the same number as the number of surface circuit patterns or plating lines.

In the embodiment, as shown in FIGS. 5, 6A and 6B, the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line is provided in four, and the upper elastic member 150 is divided into six, and the four conductive patterns 400 or surface electrodes or surface circuits or surface circuit patterns or plating lines may be electrically connected to four of the divided six parts of the upper elastic member.

As described above, since the position sensor 170 has a structure having two input terminals and two output terminals, the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line A total of 4 can be provided.

The upper elastic member 150 may be electrically connected to the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line and also electrically connected to the support member 220 . Also, the support member 220 may be electrically connected to the printed circuit board 250 .

Due to this structure, the position sensor 170 is connected to the printed circuit board 250 through the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line, upper elastic member 150 and support member 220. ) can be associated with At this time, the input terminal and output terminals of the position detection sensor 170 are independently connected to the printed circuit board 250, and the position detection sensor 170 receives current from the printed circuit board 250 or sensed values. Can be sent to the printed circuit board (250).

Meanwhile, in the embodiment, the upper elastic member 150 is divided into 6 parts, 4 of which are electrically connected to the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line and support member 220. can be connected In addition, the other two may be electrically connected to the lower elastic member 160 and the support member 220 .

The other two of the divided upper elastic members 150 may be electrically connected to the first coil 120 electrically connected to the lower elastic member 160 . At this time, since both ends of the first coil 120 need to be independently electrically connected to the printed circuit board 250, the lower elastic member 160 may be divided into two.

Therefore, both ends of the first coil 120 may be electrically connected to the printed circuit board 250 through the lower elastic member 160, two of the divided upper elastic members 150, and the support member 220, respectively. , A necessary current can be applied from the printed circuit board 250 .

At this time, two of the lower elastic member 160 divided into two and the upper elastic member 150 divided into six need to be electrically connected to each other, which can be implemented using various structures. For example, as shown in FIG. 5 , a separate conductive member may be used to connect the lower elastic member 160 and the upper elastic member 150 .

Although not shown as another embodiment, a portion of the lower elastic member 160 or the upper elastic member 150 may be bent and extended in a first direction and used as an electrical connection member.

Referring to FIGS. 5, 6A, and 6B, an embodiment of the electrical connection between the conductive pattern 400 or the surface electrode or the surface circuit or the surface circuit pattern or the plating line and the upper elastic member 150 will be described as follows. In the embodiment, the upper elastic member 150 may be divided into 6 pieces.

That is, the upper elastic member 150 includes the first upper elastic member 150-1, the second upper elastic member 150-2, the third upper elastic member 150-3, and the fourth upper elastic member 150-2. 4), the fifth upper elastic member 150-5, and the sixth upper elastic member 150-6.

At this time, the first upper elastic member 150-1, the second upper elastic member 150-2, the fourth upper elastic member 150-4, and the fifth upper elastic member 150-5 have four conduction patterns. 400 or surface electrodes or surface circuits or surface circuit patterns or plating lines, respectively, may be electrically connected to electrically connect the position sensor 170 and the printed circuit board 250 to each other.

Since the conduction pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line is formed on the surface of the bobbin 110 by the LDS method, laser is irradiated on the surface of the bobbin 110 to have a desired shape and position. A pattern with can be formed. Therefore, the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating wire formed in accordance with the pattern can be formed on the surface of the bobbin 110 in a desired shape and at a desired location.

Meanwhile, the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line and the upper elastic member 150 may be coupled to each other and electrically connected to each other by soldering. As shown in FIGS. 6A and 6B, in the embodiment, four conductive patterns 400 or surface electrodes or surface circuits or surface circuit patterns connected to the position sensor 170 having the four input or output terminals Alternatively, plating lines may be formed on the surface of the bobbin 110 so as not to be electrically shorted to each other.

In addition, in the embodiment, the four conductive patterns 400 or surface electrodes or surface circuits or surface circuit patterns or plating lines are formed by the first upper elastic member 150-1, the second upper elastic member 150-2, and the second upper elastic member 150-2. The 4 upper elastic members 150-4 and the 5 upper elastic members 150-5 may be soldered and coupled to each other and electrically connected.

Meanwhile, the third upper elastic member 150-3 and the sixth upper elastic member 150-6 are electrically connected to the two-divided lower elastic member 160, respectively, to form a first coil 120 and a printed circuit board ( 250) may serve to electrically connect each other.

Above, in order to electrically connect the position sensor 170 having both ends of the first coil 120 and four input or output terminals with the printed circuit board 250, respectively, the upper elastic member 150 divided into six parts and The two-divided lower elastic member 160 has been described, but is not limited thereto.

Accordingly, the upper elastic member 150 or the lower elastic member 160 may be divided into various numbers and methods according to the number of terminals of the component requiring an electrical connection with the printed circuit board 250 .

Meanwhile, in the bobbin 110, the surface of the bobbin 110 and the conductive pattern 400 or the surface of at least a part of the portion where the conductive pattern 400, surface electrode, surface circuit, surface circuit pattern, or plating line are formed. An adhesive (not shown) may be applied to the upper surface of the electrode or surface circuit or surface circuit pattern or plating line. The conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line formed on the surface of the bobbin 110 may be peeled off from the surface of the bobbin 110 during its formation or during use of the lens driving device. .

When the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line is peeled off from the surface of the bobbin 110, between each conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line An electrical short may occur due to contact with each other, and the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line itself may be cut off or damaged, causing malfunction of the entire lens driving device.

Therefore, in order to prevent the conductive pattern 400 or the surface electrode or the surface circuit or the surface circuit pattern or the plating line from peeling off from the surface of the bobbin 110, the conductive pattern 400 or the surface electrode or surface of the bobbin 110 An adhesive such as epoxy is applied to the area where the circuit or surface circuit pattern or plating line is formed to ensure that the conductive pattern 400 or surface electrode or surface circuit or surface circuit pattern or plating line is strongly bonded to the surface of the bobbin 110. can be maintained

7 is a view showing the arrangement of the first magnet 130 and the position sensor 170 according to an embodiment. 8 is a view showing the arrangement of the first magnet 130 and the position sensor 170 according to another embodiment.

As shown in FIG. 7, one embodiment of the first magnet 130 may be provided, and the first magnet 130 has an N pole and an S pole in a second direction perpendicular to the first direction, or It can be arranged in the third direction.

In another embodiment of the first magnet 130, as shown in FIG. 8, a plurality is provided in a first direction, and each of the first magnets 130 has an N pole and an S pole perpendicular to the first direction. It can be arranged in one second direction or a third direction.

At this time, the plurality of first magnets 130 may be arranged to have different polarities in the first direction. When a plurality of first magnets 130 are provided, the magnetic force of the first magnet 130 may increase compared to the case where there is only one. Thus, the auto focusing function of the lens driving device can be efficiently controlled.

On the other hand, when a plurality of first magnets 130 are provided, the relationship between the magnetic flux of the first magnet 130 and the vertical movement displacement of the bobbin 110 in the first direction, that is, the movement distance, is linear ( Linearity is increased so that the position sensor 170 can more accurately detect the movement distance of the bobbin 110 in the first direction. This will be described in detail below with reference to FIG. 8 .

In addition, the first magnet 130 and the position sensor 170 may be spaced apart from each other on surfaces facing each other. The position sensor 170 may measure a displacement value of the bobbin 110 moving in the first direction by detecting a change in magnetic force of the first magnet 130 according to the movement of the bobbin 110 in the first direction.

Therefore, in order for the position sensor 170 to accurately and effectively detect the change in magnetic force of the first magnet 130, the first magnet 130 and the position sensor 170 move in the second or third direction. It may be provided with a certain separation distance (w1).

At this time, the separation distance w1 between the first magnet 130 and the position sensor 170 may be provided as 0.01 mm to 0.5 mm. More appropriately, the separation distance (w1) may be provided with 0.05mm to 0.3mm.

It is appropriate that the center of the position sensor 170 exists within a certain distance from the top or bottom of the first magnet 130 in the first direction. The position sensor 170 may detect a change in magnetic force of the first magnet 130 on the central portion.

Therefore, the center of the position sensor 170 must exist within a certain distance from the first magnet 130 in the first direction so that the position sensor 170 accurately and effectively measures the change in magnetic force of the first magnet 130. can detect

At this time, the second distance w2 measured from the center of the position sensor 170 to the top or bottom of the first magnet 130 may be provided so as not to deviate from 1 mm. More appropriately, it is appropriate that the second distance w2 is provided so as not to deviate from 0.5 mm.

7 and 8 show a case where the center of the position sensor 170 is above the first magnet 130, and accordingly, the second distance w2 is set to the center of the position sensor 170. It is shown as being measured up to the top of the first magnet 130 in .

However, when the center of the position sensor 170 is below the first magnet 130, the second distance w2 is the distance between the center of the position sensor 170 and the first magnet 130. It is measured to the bottom.

9 is a graph showing the relationship between the magnetic flux of the magnet and the moving distance of the bobbin 110 in the first direction. At this time, the movement distance in the first direction may be measured by the position sensor 170 .

In the graph, S1 curve represents a case in which two first magnets 130 are provided in the lens driving device, and S2 curve represents a case in which one first magnet 130 is provided.

As can be seen in FIG. 9 , when two first magnets 130 are provided, the curve shows a more linear change than when the first magnet 130 is provided with one. As the linearity of the curve increases, the position sensor 170 can more accurately measure the moving distance of the bobbin 110 in the first direction.

Therefore, it may be appropriate to have a plurality of first magnets 130 in terms of accuracy in measuring the moving distance of the bobbin 110 of the position sensor 170 in the first direction.

However, whether the lens driving device includes one first magnet 130 or two or more first magnets 130 may be appropriately selected by reviewing the overall structure of the lens driving device, manufacturing cost, and other design considerations.

10 is a graph showing test results of driving characteristics of a lens driving device according to an exemplary embodiment. In the graph, GAIN can be converted into a displacement value of the position sensor 170 in the first direction through appropriate conversion to a sensing value of the position sensor 170 .

In the graph, the gain of the lens driving device of the embodiment in which the position sensor 170 is spaced apart from the first coil 120 in the first direction from the bobbin 110 is indicated by L1.

In the graph, the position sensor 170 has a structure in which the bobbin 110 is not spaced apart from the first coil 120 in the first direction, that is, when viewed in the second or third direction, the position sensor 170 ) and the first coil 120 are all or partly overlapped, the gain of the lens driving device is denoted by L2.

In the graph, the phase (PHASE) can be converted to the displacement value of the first direction of the bobbin 110 through appropriate conversion to the current input value of the first coil 120. In the graph, the phase is indicated by L3.

Since the displacement value of the position sensor 170 in the first direction matches the displacement value of the bobbin 110 in the first direction, the error in the sensing value of the position sensor 170 can be reduced as L1 or L2 matches L3 as much as possible. there is.

Considering section A in the graph, it can be seen that the L3 graph continuously decreases as the frequency (FREQUENCY) increases. However, it can be seen that the L1 or L2 graph has an increasing section in section A.

Again, compare L1 and L2 graphs in section A. As the frequency increases, the gain of L1 increases significantly compared to that of L3, and the increase shows a generally constant trend.

As the frequency increases, the gain of L2 increases compared to that of L3, but the range of increase is significantly lower than that of L1, and as the frequency increases, the gain decreases.

Comparing the L1 and L2 graphs, L2 shows a trend closer to L3 than L1. As a result, the lens driving device of the embodiment in which the position sensor 170 is spaced apart from the first coil 120 in the first direction on the bobbin 110 is different from the other lens driving device described above. 1 shows that the sensing error value of the position sensor 170 by the current flowing through the coil 120 is small.

In the embodiment, the position sensor 170 provided on the bobbin 110 and the upper elastic band are provided on the bobbin 110 by using the conductive pattern 400 formed on the surface of the bobbin 110 or the surface electrode or surface circuit or surface circuit pattern or plating line. By electrically connecting the members 150, the structure of the lens driving device can be simplified.

In addition, by using the conductive pattern 400 formed on the surface of the bobbin 110 or surface electrode or surface circuit or surface circuit pattern or plating line, a separate structure for electrical connection, compared to the case of using a conductive member, the lens There is an effect of significantly reducing interference between each part constituting the driving device.

Meanwhile, the lens driving device according to the above-described embodiment may be used in various fields, for example, a camera module. For example, the camera module can be applied to mobile devices such as mobile phones.

The camera module according to the embodiment may include a lens barrel coupled to the bobbin 110, an image sensor (not shown), a printed circuit board 250, and an optical system.

The lens barrel is as described above, and the printed circuit board 250 may form a bottom surface of the camera module from a portion where the image sensor is mounted.

Also, the optical system may include at least one lens that transmits an image to the image sensor. At this time, an actuator module capable of performing an auto focusing function and a hand shake compensation 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. The lens driving device according to the above-described embodiment may serve as an actuator module that performs both an auto-focusing function and a hand-shake correction function.

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 210 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 210 may support the lower side of the holder member.

A separate terminal member may be installed on the base 210 to conduct electricity with the printed circuit board 250, or the terminal may be integrally formed using a surface electrode or the like. Meanwhile, the base 210 may function as a sensor holder to protect the image sensor, and in this case, a protrusion may be formed downward along a side surface of the base 210 . However, this is not an essential configuration, and although not shown, a separate sensor holder may be disposed below the base 210 to perform its role.

Although only a few have been described as described above in relation to the embodiments, various other forms of implementation are possible. The technical contents of the above-described embodiments may be combined in various forms unless they are incompatible with each other, and through this, may be implemented in a new embodiment.

110: bobbin
111: seating groove
120: first coil
130: first magnet
140: housing
150: upper elastic member
160: lower elastic member
170: position sensor
220: support member
250: printed circuit board
400: conduction pattern
410: one end of the conduction pattern
w1: Separation distance
w2: second distance

Claims (20)

housing;
a bobbin disposed within the housing;
a first magnet disposed in the housing;
a first coil disposed on the bobbin and moving the bobbin in an optical axis direction by interaction with the first magnet;
a sensing magnet disposed in the housing;
a position sensor disposed on the bobbin and moving along with the bobbin in the optical axis direction;
an upper elastic member coupled to an upper portion of the bobbin and an upper portion of the housing;
a circuit board disposed below the housing;
a support member electrically connecting the upper elastic member and the circuit board; and
A conductive pattern formed on an outer surface of the bobbin and electrically connecting the position sensor and the upper elastic member,
The bobbin includes a support protrusion coupled with a portion of the upper elastic member,
The position detection sensor includes a position detection sensor unit for detecting a displacement of the bobbin in the optical axis direction by detecting magnetic force of the sensing magnet and a driving driver;
One end of the conductive pattern is coupled to the position sensor by solder, and the other end of the conductive pattern is coupled to the upper elastic member by solder,
The one end of the conductive pattern is in contact with the position sensor and the bobbin,
The lens driving device of claim 1 , wherein an upper surface of the position sensor is disposed at a lower position than the upper elastic member, and the conduction pattern is disposed at a position lower than the part of the upper elastic member. According to claim 1,
and a second coil electrically connected to the circuit board and moving the housing in a direction perpendicular to the optical axis direction by interaction with the first magnet. According to claim 1,
The upper elastic member includes a plurality of upper elastic members,
The conduction pattern includes a plurality of conduction patterns,
Each of the plurality of conductive patterns is electrically connected to a corresponding one of the plurality of upper elastic members. According to claim 3,
The support member includes a plurality of support members corresponding to the plurality of upper elastic members,
Each of the plurality of support members is coupled to a corresponding one of the plurality of upper elastic members. According to claim 4,
The lens driving device of claim 1 , wherein the support member is disposed at a corner of the housing. delete According to claim 1,
The lens driving device wherein the position detection sensor is disposed spaced apart from the first coil. According to claim 7,
The first coil is disposed below the position sensor. According to claim 1,
a base disposed below the circuit board; and
A lens driving device including a lower elastic member coupled to a lower portion of the bobbin and a lower portion of the housing. According to claim 1,
N poles and S poles of the first magnet are arranged to face each other in a direction perpendicular to the optical axis. According to claim 9,
The circuit board includes a terminal surface having a bent shape, and a plurality of terminals formed on the terminal surface. delete According to claim 1,
The conductive pattern is formed on the surface of the bobbin by a laser direct structuring (LDS) method. According to claim 1,
The upper elastic member includes a through hole coupled with the support protrusion. According to claim 1,
The upper elastic member includes four upper elastic members,
The driving driver is electrically connected to the four upper elastic members. Base;
a circuit board disposed on the base;
a housing disposed on the circuit board;
a bobbin disposed within the housing;
a first magnet disposed in the housing;
a first coil disposed on the bobbin and moving the bobbin in an optical axis direction by interaction with the first magnet;
a sensing magnet coupled to the housing;
a circuit element coupled to the bobbin to be disposed on the opposite side of the sensing magnet and moving together with the bobbin in the direction of the optical axis;
an upper elastic member coupled to an upper surface of the bobbin and an upper surface of the housing;
a support member electrically connecting the upper elastic member and the circuit board; and
A conductive pattern formed on an outer circumferential surface of the bobbin and electrically connecting the circuit element and the upper elastic member,
The bobbin includes a support protrusion coupled with a portion of the upper elastic member,
One end of the conductive pattern is coupled to the circuit element by solder, and the other end of the conductive pattern is coupled to the upper elastic member by solder,
The one end of the conductive pattern is in contact with the circuit element and the bobbin,
The circuit element includes a position detection sensor unit and a driving driver for detecting displacement of the bobbin in the optical axis direction,
An upper surface of the circuit element is disposed at a position lower than the upper elastic member, and the conductive pattern is disposed at a position lower than the part of the upper elastic member. delete According to claim 16,
The first coil is disposed between the circuit element and the circuit board. delete a lens driving device according to any one of claims 1 to 5, 7 to 11, 13 to 16, and 18;
a lens barrel coupled to the bobbin; and
A camera module including an image sensor.

Images