KR20110111624A - Lens actuator preventing particle induction and process thereof - Google Patents

Abstract

The present invention provides a lens actuator for image capturing a camera module that is adopted in a mobile communication device, the lens for image capturing including a driving unit disposed around the lens unit and an adhesive layer applied along the outer circumferential surface of the case member accommodating the driving unit. An actuator and a method of manufacturing the same are provided. According to the present invention, it is possible to miniaturize the lens actuator and to prevent the inflow of foreign substances or moisture and shield electromagnetic waves generated from external components of the camera module.

Description

Lens Actuator Preventing Particle Induction and Process Thereof}

The present invention relates to a lens actuator constituting a camera module, and more particularly, to a lens actuator for an image pickup device which can be adopted in a portable terminal to block the inflow of dust from outside and at the same time, to be compact and lightweight.

As digital technology advances, small optical devices as image pickup devices have been adopted in mobile communication devices such as mobile phones, which were used only for telephony in the past. However, the camera module mounted in the digital image capturing apparatus is provided with a variety of lens actuators as driving devices for zooming or auto-focusing, and has a suitable number inside. The focus and / or magnification are adjusted by moving the formed lens along the optical axis direction.

Conventionally, in the camera module mounted on such a small optical device, a mechanical apparatus of a rotating motor type is used to automatically adjust the focus of a photographed subject, but the mechanical apparatus has a problem that it is difficult to adjust the focus finely and it is difficult to miniaturize it. .

Accordingly, step motors, piezoelectric elements, and voice coil motors (VCM) are used to implement stable focusing while meeting the trend of miniaturization and weight reduction required in mobile communication devices having camera modules mounted in mobile communication devices. ), Etc. are adopted. Here, the voice coil motor (VCM) or the voice coil actuator (VCA) method refers to a method of precisely focusing using the induction magnetic force of the permanent magnet and the coil, and is a camera currently employed in mobile communication devices. Voice coil motor method is widely used in the module. 1 is a cross-sectional view schematically showing a lens actuator 1 of a VCM method applied to a conventional mobile communication device.

As shown in FIG. 1, the lens actuator 1 applied to a conventional mobile communication device is a cylindrical carrier for accommodating the lens unit 10, which is generally composed of a plurality of focusing lenses L and forms an image pickup area. (12), a substantially cylindrical magnet (20) disposed along the outer periphery of the carrier (12), a yoke (22) having a substantially U-shaped cross section so as to control the magnetic force of the magnet (20), Coils 24 arranged on the outer peripheral surface of the lower end of the carrier 12 are arranged. In such a VCM-type lens actuator, the magnet 20 generating the magnetic force and the coil 24 to which the current is applied are disposed to face each other, and the coil 24 interacts in the magnetic force generated by the magnet 20. The carrier 12 is driven by the Lorentz force generated in the vertical direction of the current and the magnetic field, that is, in the optical axis direction by the induced magnetic force. In addition, in order to control the driving force of the carrier 12 to a certain limit, the upper spring 32 and the lower spring 34 having appropriate elastic force are fastened to the upper and lower ends of the carrier 12, respectively. Meanwhile, a cover surrounding the outer circumference of the yoke 22 and the upper end of the upper spring 32 so that the aforementioned carrier 12 and the magnet 20 as the driving unit and the yoke 22 can be stably assembled at a fixed position ( 42 is assembled, and the base 44 is coupled to the lower and outer periphery of the carrier 12. Recently, a mobile communication device equipped with a lens actuator with an image sensor of several million pixels or more is generally sold on the market, and in accordance with the trend toward miniaturization and multifunction of mobile communication devices, the width D of the lens actuator 1 is generally 1.0. It is necessary to set it to less than mm.

In particular, in the process of assembling the lens actuator of the VCM method, the cover 42 and the base 44 must be coupled to accommodate the magnet 20, the yoke 22, and the coil 24. This is assembled. However, in this process, foreign matters such as external dust or moisture are introduced into the image capturing area through minute gaps between components. Accordingly, when the dust test is performed as illustrated in FIG. 2, a large amount of dust flows into the conventional image sensor region of the lens actuator, particularly in the center where the lens L is formed. Misfocused dust can be mistaken for a subject, resulting in poor focusing, which in turn leads to deterioration of the quality of the photographed image.

In order to solve this problem, a method for blocking foreign substances such as dust or moisture may be considered on the outside of the lens actuator. 3 schematically illustrates a conventional VCM lens actuator having such a configuration, and separately combines the shield case 50 to the outside and the top of the cover 42 and the base 44. However, by combining the shield case 50 may block the inflow of the above-mentioned foreign matter, but the addition of this configuration is inevitable to increase the size of the lens actuator itself. Increasing the space occupied by lens actuators and camera modules including such lens actuators in mobile communication devices, in which modules with various functions are assembled together, cannot meet the trend of mobile communication devices aiming for miniaturization and light weight.

In particular, as described above, it is generally necessary to keep the horizontal width D of the lens actuator 1 to less than 1.0 mm. The horizontal width d of the newly constructed shield case 50 is about to prevent the inflow of foreign matter. It is about 0.1 mm. When the shield case 50 is coupled in a form surrounding the outer periphery of the cover 42 and the base 44, the width of the lens actuator 1 is increased by about 0.2 mm due to the addition of the shield case 50. do. This increase in size may be a significant burden from the standpoint of the manufacturer of the camera module including the lens actuator 1 or the manufacturer of the mobile communication device equipped with the camera module. In order to meet the demand for miniaturization, the size of the magnet 20, the yoke 22, and the coil 24 forming the driving unit must be reduced, in which case, it is difficult to obtain a desired driving force.

The present invention has been proposed to solve the above problems, the main object of the present invention is to shield the electromagnetic waves caused from foreign matter, as well as foreign matters, as well as foreign matters such as dust or moisture from the outside. An object of the present invention is to provide a lens actuator for image capturing employed in a mobile communication device.

It is another object of the present invention to provide a lens actuator for image capturing which can improve image quality by preventing focusing errors while satisfying the requirements of miniaturization and weight reduction.

Still another object of the present invention is to provide a lens actuator for a camera module, which enables a particularly stable and stable coupling between case members to enable stable focusing.

Other advantages and objects of the present invention will become more apparent from the following detailed description of the invention and the accompanying drawings.

In order to solve the above object, the present invention proposes a form in which an adhesive is applied to the outside of the lens actuator adopting the VCM method.

Specifically, according to an aspect of the present invention, a lens actuator for image pickup constituting a camera module that is adopted in a mobile communication device, comprising: a lens unit for receiving a lens unit for photographing a subject and movable in the optical axis direction; A driving unit for moving the lens unit in the optical axis direction by a driving force caused by the interaction of a magnet and a coil disposed around the lens unit; A case member accommodating the lens portion and the driving portion, the case member including a cover coupled to an outer periphery of the driving portion, and a base supporting a lower end of the lens portion; And an adhesive layer applied along an outer circumferential surface of the cover.

In this case, the material forming the adhesive layer may be a curable material, and may include, for example, an epoxy resin, a urethane resin, an acrylic resin, a silicone resin, a rubber resin, or an adhesive made of a ceramic material, a waterproofing agent, or an electromagnetic wave blocking agent.

In particular, the driving unit is wound around the magnet portion disposed around the lens unit, the first yoke disposed above the magnet, the second yoke disposed below the magnet, and the outer circumferential surface of the lens unit, and the lens unit It moves in conjunction with the and includes a coil disposed opposite to the inner peripheral surface of the second yoke.

Preferably, the lens unit includes a cylindrical carrier and a lens unit assembled in the carrier.

According to another aspect of the invention, winding the drive coil to the outer peripheral surface of the carrier and fastening the second elastic member to the lower end of the carrier to form a coil assembly; Receiving a first elastic member, yoke, and magnet on an inner surface of the upper cover, and then combining the upper cover and the lower cover to form a cover assembly; After placing the coil assembly on an upper surface of a base, engaging the cover assembly with the base; And applying an adhesive layer to the outside of the lens actuator coupled to the cover assembly and the base.

The present invention proposes a lens actuator for image capturing that can shield electromagnetic waves generated from external foreign matter and adjacent components as a lens actuator that can be stably mounted on a small optical device such as a mobile communication device by adopting the VCM method. Doing. Accordingly, the focusing error can be prevented due to the influx of foreign substances or the influence of electromagnetic waves, thereby preventing the deterioration of the image quality.

In particular, the present invention achieves such a technical effect but does not increase the size of the entire lens actuator, so that the size and weight can be simultaneously reduced.

In addition, the lens actuator of the present invention firmly assembled the case member so that the driving coupling portion such as the carrier housing the lens and the driving portion disposed along the outer circumferential surface thereof can be assembled at a stable position. Accordingly, the case member can be prevented from being separated even during the test process or an external impact, thereby enabling stable focusing.

1 is a cross-sectional view schematically showing a lens actuator employed in a conventional mobile communication terminal.
Figure 2 is a photograph measuring the result after performing a dust test on a conventional lens actuator.
3 is a schematic cross-sectional view of a lens actuator adopting a shield case as a lens actuator adopted in a conventional mobile communication terminal.
Figure 4 is an exploded perspective view schematically showing a coupling relationship between the components constituting the lens actuator constituting the camera module adopted in the mobile communication terminal according to the present invention.
5 is an overall perspective view showing a state in which the lens actuator according to the present invention is assembled.
6 is a cross-sectional view taken along the VI-VI line of FIG. 5.
Figure 7 is an exploded perspective view schematically showing the coupling relationship between the case members forming the outline of the lens actuator according to the present invention.
8 is a flow-chart schematically illustrating a process for assembling a lens actuator according to the present invention.
Figure 9 is a side photograph of the lens actuator after the adhesive is applied in accordance with the present invention.
10 is a photograph showing the test results after performing the dust test on the lens actuator according to the present invention.

The present inventors endeavor to solve the problems of the conventional lens actuator described above, and then apply an appropriate adhesive, waterproof agent, etc. to the outer side of the lens actuator for a mobile communication device capable of auto-focusing, thereby influencing the influx of foreign matter or electromagnetic waves. The present invention has been completed by focusing on being able to block and at the same time implementing stable focusing through a firm coupling of a case member. EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated, referring an accompanying drawing.

4 is an exploded perspective view schematically showing a coupling relationship between components constituting an auto-focusing lens actuator constituting a camera module adopted in a mobile communication terminal according to the present invention, and FIG. 5 is a lens actuator of the present invention. Is a perspective view showing an assembled state, and FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. 5. The lens actuator 100 for image capturing according to the present invention constitutes a camera module in a small optical device or an image pickup device such as, for example, a mobile communication device, and describes a so-called VCM method as an example.

Here, the lens actuator 100 for image capturing according to the present invention is a lens module 200 which is a lens module corresponding to a movable part moving in the optical axis direction in the imaging process of the subject and the movement of the lens unit 200. The driving unit 300 disposed along the outer periphery of the lens unit 200 to generate a driving force for the elastic member, elastic members 410 and 420 for controlling the driving force by the driving unit 300, and the lens unit 200. And / or the case member 500 coupled in a form surrounding the outer periphery of the driving unit 300.

The lens unit 200, which is formed at the center of the lens actuator 100 and defines an area for image pickup of a subject, includes a lens unit 210 having one or more, typically a plurality of lenses, having an appropriate curvature and size, and It consists of a substantially cylindrical carrier 220 having a hollow portion for accommodating the lens unit 210. The lens unit 210 may be assembled inside the carrier 220, for example, in the form of a lens holder assembly, or in a form assembled such that the optical axis for each lens coincides. Specifically, the lens unit 210 in which at least one lens L through which incident light is transmitted is aligned and arranged in the optical axis direction forms a lens receiving portion as a hollow cylinder, and has a substantially cylindrical portion having a hollow portion outside the lens unit 210. The carrier 220 of the sieve is fastened. To this end, the lens unit 210 is connected to the carrier by a method of combining the first thread 212 formed along the outer circumference of the lens unit 210 and the second thread 222 formed along the inner circumferential surface of the hollow carrier 220. It is firmly fastened to the inside of the 220 to constitute the lens unit 200 as a lens module. Accordingly, as the carrier 220 moves in the optical axis direction, when the lens unit 210 assembled therein moves, the distance between the lens L and the image sensor (not shown), that is, the focal length of the subject is changed. Implement focusing. Here, the carrier 220 may be integrally manufactured by press molding using a plastic material of an insulating resin such as polycarbonate containing glass, for example. Accordingly, the carrier 220 is accommodated in the upper cover 510, the lower cover 520, and the base 530 to be movable up and down in the case member 500, which will be described later.

In addition, a flange 224 extending outward is formed along the lower outer circumferential surface of the substantially cylindrical carrier 220 so that the driving coil 340 electrically connected to the external power source can be seated. The locking end 226 protrudes outward to the upper end of the 224. At this time, the engaging end 226 may be configured in a continuous form along the outer circumferential surface of the flange 224, as shown in the plurality of the same interval only a predetermined area of the outer circumferential surface of the carrier 220 of the top of the flange 224 It may be formed in a shape projecting toward the outside.

Meanwhile, in order to control an auto-focusing (AF) process for the subject along the outer periphery of the carrier 220 constituting the outer portion of the lens unit 200, the driving unit 300 and Many components for controlling operation are appropriately arranged and combined, which will be described. The lens actuator 100 according to the present invention includes a driving unit 300 of a so-called voice coil motor (VCM) method. In particular, the position of the magnet 310 is fixed while the driving coil 340 is a lens unit ( The so-called 'coil-operated' driving unit 300 whose position changes with the movement of 200 is formed. The driving unit 300 moves an outer periphery of the carrier 220 to move the carrier 220 and the lens unit 210 accommodated in the carrier 220 in the optical axis direction to adjust the focus of the image of the subject. Are arranged accordingly. The driving unit 300 is largely a magnet 310 for generating a magnetic field, yokes 320 and 330 disposed at the top and bottom of the magnet 310 to control the flow of the magnetic field generated from the magnet 310, that is, the magnetic flux. And a driving coil 340 that receives a predetermined power from an external power source.

The magnet 310 may use a permanent magnet used in a conventional voice coil motor method, for example, a neodymium-based permanent magnet, and may be spaced apart from the upper circumferential surface of the carrier 220 at a predetermined interval. It is approximately ring-shaped with a hollow part. For example, the magnet 310 may be disposed such that its upper end has the polarity of the S pole and the lower end thereof, or the reverse direction thereof.

On the other hand, to control the flow (magnetic flux) of the magnetic force generated in the magnet 310, for example, yoke (320, 330) that can be made of a conductive material such as iron, cold rolled steel or nickel having excellent magnetic transmittance ) Is arranged around the magnet 310. Specifically, the first yoke 320 having a cross section extending along the upper end and the inner circumferential surface of the magnet 310, and a cross section having a substantially “a” shape, and the coil 340 extending downward from the bottom of the outer circumferential side of the magnet 310. Has a second yoke 330 (top-plate) disposed opposite the outer circumferential surface thereof.

In this case, since the upper end 322 of the first yoke 320 is extended outward, the first elastic member 410 described later may be stably positioned on the upper surface of the upper end 322 of the first yoke 320. The upper end 322 of the first yoke 320 is seated in contact with the upper surface of the magnet 310. On the other hand, the inner circumferential surface of the first yoke 320 is in close contact with the outer circumferential surface of the carrier 220, the lower outer circumferential surface is configured to face the inner circumferential surface of the magnet 310 described above, the magnetic flux generated from the magnet 310 is optical axis It can only flow in the direction perpendicular to. That is, since the first yoke 320 surrounds the upper end and the inner circumferential surface of the magnet 310, leakage of magnetic flux may be reduced at the upper inner circumferential surface of the magnet 310. In addition, since the lower outer circumferential surface of the first yoke 320 is disposed opposite to the upper inner circumferential surface of the driving coil 340, the magnetic flux generated by the magnet 310 can be efficiently controlled.

On the other hand, the second yoke 330 having a substantially ring shape is disposed in a form in which the upper surface thereof is in contact with the outer bottom surface of the magnet 310, the outer diameter is substantially the same as the outer diameter of the magnet 310. On the other hand, the inner diameter of the second yoke 330 is formed to form a larger hollow than the magnet 310, the inner circumferential surface of the second yoke 330 may be disposed opposite to the outer circumferential surface of the drive coil 340 to be described later have. As such, while the second yoke 330 is in contact with the bottom surface of the magnet 310, the inner circumferential surface of the second yoke 330 is disposed opposite to the outer circumferential surface of the driving coil 340 wound around the carrier 220. The magnetic flux can be efficiently controlled while suppressing leakage magnetic flux from the magnet 310.

In particular, the driving coil 340 is electrically connected to an external power source to interact with the magnetic field generated by the magnet 310 to generate the Lorentz force, that is, the driving force due to the electromagnetic force, at the bottom of the carrier 220. The upper surface of the flange 224 protruding outward is seated. Accordingly, the driving coil 340 is disposed along the outer periphery of the carrier 220, and is configured to change its position in the optical axis direction together with the lens unit 200. At this time, the upper end of the driving coil 340 is spaced apart from the bottom of the magnet 310 by a predetermined interval, the inner circumferential surface of the driving coil 340 is disposed opposite to the lower outer peripheral surface of the first yoke 320, the driving coil The outer circumferential surface of 340 is disposed opposite to the inner circumferential surface of the second yoke 330, respectively. In particular, the locking end 226 is formed on the upper surface of the flange 224 formed on the outer circumference of the carrier 220 in which the driving coil 340 is wound, so that the first yoke 320 when the carrier 220 moves upward in the optical axis direction. Limiting movement of the carrier 220 by contacting the inner bottom of the.

The magnetic field generated by the magnet 310 penetrates the driving coil 340 formed as described above, thereby generating electromagnetic force, that is, Lorentz force due to the interaction of the magnetic field and the electric field. That is, when a current is applied to the driving coil 340 through an electrode (not shown) connected to the coil 340 from an external electronic circuit, an electric field is formed in the driving coil 340. However, since the magnetic field is formed around the drive coil 340 from the magnet 310 via the yokes 320 and 340, the carrier 220 coupled to the drive coil 340 by the Lorentz force. And the lens unit 210 assembled therein is driven in the optical axis direction perpendicular to the magnetic field direction.

As a result, the driving coil 340 seated on the carrier 220 through the flange 224 at the bottom of the carrier 220 functions as a movable part which repeats the up and down reciprocating motion along the optical axis to adjust the focusing on the photographed subject. The magnet 310 and the yoke 320 and 330 function as a fixing part whose position is fixed, and the movable part and the fixing part form a kind of drive coupling part through proper arrangement. The driving coil 340 is generally formed by winding in a substantially cylindrical shape using a copper alloy wire, and both ends of the driving coil 340 are drawn downward from the bottom of the base 530 and are formed of a conductor such as a copper alloy. The electrodes (not shown) may be connected to each other by soldering or the like. Alternatively, both ends of the driving coil 340 may be electrically connected to the elastic members 410 and 420 described later, and the ends of the elastic members 410 and 420 may be connected to the electrodes.

Next, the elastic members 410 and 420, which provide a restoring force for the movement of the lens unit 200 by the driving force of the driving unit 300 and provide a feeding path to the driving coil 340, will be described. Carrier 220 and coil 340 repeating the up and down reciprocating motion along the optical axis, and the upper end of the carrier 220 to fasten between the magnet 310 and the yoke (320, 330) fixed position Elastic members 410 and 420 are formed at the lower ends, respectively.

The elastic members 410 and 420 supply current to both ends of the coil 340, and impart restoring force as the carrier 220 moves in the optical axis direction, thereby determining the relative position of the carrier 220. It is composed. To this end, the elastic members 410 and 420 are firmly coupled to the upper and lower ends of the carrier 220, respectively. The elastic members 410 and 420 are provided with a carrier 220 / coil 340 as a movable part and a magnet as a fixed part. The 310 and yoke 320, 330 is preferably installed in the vicinity of the coupling of the upper and lower surfaces of the movable portion and the fixed portion so as to be elastically connected to each other.

At this time, the elastic member is a first elastic member 410 disposed on the upper surface of the first yoke 320 and the upper end of the carrier 220, and the first member is installed to the bottom surface of the carrier 220 and the lower cover 520 to be described later 2 may include an elastic member 420, and these elastic members 410 and 420 may have a plate-spring shape. In particular, the first elastic member 410 and / or the second elastic member 420 may be wavy plate-springs with serpentine wavy grooves 412, 422 along the circumferential surface thereof. However, by having such an appearance, it is possible to alleviate an external shock and to improve the restoring force.

As described above, the elastic members 410 and 420 having a leaf spring shape support the driving unit 300 and exert a repulsion force against the driving force obtained from the driving unit 300. Thus, the lens unit 200 rapidly moves in the optical axis direction during the focusing process. While preventing the movement, it provides a feed path for the application of the current, for this purpose it is necessary to electrically connect between the elastic members (410, 420) and the coil 340. That is, in order to adjust the focus on the subject, the elastic members 410 and 420 are fastened between the movable parts 220 and 340 and the fixing parts 310, 320 and 330. In addition, it is necessary to apply a predetermined current to the coil 340 according to the image of the subject, wherein at least one of the elastic members 410 and 420 formed at the upper and lower ends of the lens actuator 100 is provided. One end may be configured to be connected to an external power source. For example, in the drawing, a feed terminal 426 is formed on one side of the second elastic member 420, and the feed terminal 426 extends along the outer circumferential surface of the base 530 to be finally connected to an external power source. . On the other hand, unlike the first elastic member 410 having a substantially circular plane, the second elastic member 420 has a substantially quadrangular shape with a through hole 424 formed at four corners. The fastening end 536 which protrudes upward from each part of the base 530 mentioned later is comprised so that it may pass.

In addition, according to the present invention, a guide ring 430, which is preferably made of a magnetic material, is disposed on the upper surface of the first elastic member 410 in the form of a thin metal plate. The guide ring 430 has a ring shape having substantially the same inner diameter as the first elastic member 410. The guide ring 430 keeps the first elastic member 410 in close contact with the carrier 220 without deviation, thereby improving the impact resistance of the lens actuator 100, and the first elastic member 100 during a drop impact. It can prevent the deformation of the mechanical stroke. In addition, as the guide ring 430 is firmly fitted to the inner circumferential surface of the upper cover 510, rotation to prevent the carrier 220 from rotating when the case member is assembled to the outer circumferential surface of the carrier 220. It can also function as a prevention member. To this end, a plurality of guide locking ends 432 extend to the outer circumferential surface of the guide ring 430 to the outside. The guide locking end 432 is preferably formed every 90 mm, and is fitted into the guide groove 516 formed on the inner circumferential surface of the upper edge corner of the upper cover 410 whose planar shape is approximately square. Accordingly, the first elastic member 410 prevents deformation of the first elastic member 410 while the outer circumferential portion of the first elastic member 410 is fitted between the bottom of the upper cover 510 and the upper end of the first yoke 320. The member 410 may be stably seated on the top of the carrier 220.

On the other hand, the case member 500 having a stable and robust coupling while providing an appearance of the lens actuator 100 for image capturing according to the present invention has an overall quadrangular shape in plan view. The case member 500 includes a cover 502 (refer to FIG. 7) that forms the outermost portion of the lens actuator 100 and a base 530 that is coupled to the cover 502 while supporting the bottom surface of the carrier 220. Separated by. The case member 500 may be made of, for example, an insulating resin, and the coupling relationship between these case members 500 will be described with reference to FIG. 7. 7 is an exploded perspective view schematically illustrating a coupling relationship between case members forming an outline of a lens actuator according to the present invention.

The cover 502 includes a top cover 510 disposed on an upper surface of the outer circumferential portion of the first elastic member 420 so as to form an appearance of the lens actuator 100, and a bottom surface of each corner of the upper cover 510 penetrates the second cover. The bottom surface of the yoke 330 may be divided into a lower cover 520. The upper cover 510 provides an upper shape of the lens actuator 100, and has a hollow area for accommodating the carrier 220 and the driver 300, and is quadrangular in plan view. The center of the side portion constituting the side of the upper cover 510 is open while the corner portion is formed with a coupling portion 511 extending downward, the magnet 310 forming a drive portion, The yoke 320, 330, the first elastic member 410, and the guide ring 430 are configured to not be separated. In addition, the lower cover 520 and the base 530 may be stably and firmly coupled to the lower cover 520 and the base 530 through the coupling part 511 extending downward in each part of the upper cover 510.

Looking at the configuration and shape of the coupling portion 511 formed in each of the upper cover 510 in more detail, the coupling groove extending in the vertical direction along the outer circumferential surface of the upper portion of the cover (510), and has a concave shape in the center ( 512 and the protruding ends 514a and 514b which extend downward from the sides adjacent to the respective portions of the upper cover 510, preferably formed at both sides of the coupling groove 512, and the upper cover 510. A coupling protrusion 518 extending downward in the form of a cylinder, for example, on the inner peripheral surface side of each part. Coupling groove 512 is divided into a first coupling groove 513a having a shape recessed inward compared to the bottom, and a second coupling groove (hook coupling groove, 513c) at the bottom, and the first coupling groove (513a) and A stepped portion 513b is formed between the second coupling grooves 513c. At this time, the stepped portion 513b may protrude horizontally toward the outside, but may preferably protrude in the form of forming an inclined surface at a predetermined angle in the downward direction.

Meanwhile, the lower cover 520 coupled to the upper cover 510 also has a hollow portion and has a substantially quadrangular shape to correspond to the upper cover 510. The inner diameter of the lower cover 520 is configured to be slightly smaller than the second yoke 330 so that the second yoke 330 may be seated on the upper end of the lower cover 520 to face the outer peripheral surface of the lower end of the carrier 220. Is located. In addition, the lower cover 520 is formed so that the size and shape thereof may correspond to the shape of the outer circumferential portion of the second elastic member 420 disposed at the lower end thereof, so that the lower cover 520 is the second elastic member 420. Press to secure the center and outer periphery of

In particular, each portion of the lower cover 520 is configured to correspond to the upper cover 510 while providing a path for the hook 536 of the base 530. In detail, a hook through-groove 522 is formed on the outer circumferential surface of each lower cover 520, so that the hook 536 protruding upward from each portion of the base 530 is coupled to the upper cover 510. to provide. In addition, an upper cover through hole 524 is formed at a side portion adjacent to each portion of the lower cover 510 to insert the protruding ends 514a and 514b of the upper cover 510. The upper cover through hole 524 is preferably formed at both sides 524a and 524b about the hook through hole 522. In addition, a fastening hole 526 is formed in the inner circumferential side of the hook through hole 522 of the lower cover 520, so that the coupling protrusion 518 extending downward from the inner circumferential side of each part of the upper cover 510 may be fastened.

Through the above method, the lower cover 520 allows the driving unit 300 of the lens actuator 100 to be stably assembled to the inner circumferential surface of the upper cover 510, and at the same time, the magnets 310 and the yokes 320 and 330. Is prevented from being separated from the lower cover 520. As a result, since the upper cover 510 and the lower cover 520 are coupled by a plurality of corresponding fastening means, a much better coupling can be achieved, and thus stable focusing can be realized since they are not separated from external impact or testing.

Meanwhile, by firmly supporting the lower end of the carrier 220 and the lower end of the lower cover 520, the base 530 having an approximately quadrangular shape in plan view is provided to provide a lower outer shape of the lens actuator 100. The lower end of the carrier 220 is surrounded. The center of the base 530 forms a window active window 535 having a hollow enough to accommodate the carrier 220, so that an image of the subject may be transmitted to a filter or an image sensor (not shown). In particular, the inner circumferential side of the base 530 is configured to support the lower end of the carrier 220. Specifically, the support end 532 protruding upward to contact the boss (not shown) formed at the bottom of the carrier 220, and the foreign matter blocking portion 534 to which the adhesive is applied to prevent foreign substances from entering. Is formed.

Typically, an external foreign material is generated during the assembly of the lens actuator 100 or the image capturing process, so that the window active window of the base 530 passes through a gap between the outer periphery of the carrier 220 and the driving unit 300. 535 may be introduced. When a foreign matter flows into the window active window 535, a filter or an image sensor fastened to the bottom of the base 530 may misunderstand the foreign matter as a part of the subject and cause a focusing error. In order to prevent this, the foreign matter blocking part 534 having a flat cross section prevents foreign matter from entering the window active window 535 by applying an adhesive. That is, the foreign material blocking unit 534 is formed outside the optical system in which the subject is actually photographed, and thus, fine foreign matter may be blocked from entering the optical system for capturing the subject. At this time, when the outer periphery of the window active window 535 is coated with an adhesive, it is difficult to move in the optical axis direction after the carrier 220 and the base 530 contact. In order to prevent this, in the present invention, four support ends 532 are projected upward on the upper surface between the inner peripheral surface of the side of the base 530 and the window active window 535 to contact the bottom of the carrier 220. The support end 532 is configured such that no adhesive is applied. Accordingly, when the carrier 220 is disposed at the lowest position, the boss (not shown) at the bottom of the carrier 220 may be supported by the upper surface of the support end 532.

In addition, a hook 536 is formed to extend upward from each part of the base 530 having a substantially quadrilateral shape so that the base 530 can be stably coupled to the cover 502 described above. The hook 536 may be fitted into a coupling groove 512 formed in the outer circumferential surface of each part of the upper cover 510 as shown in FIG. 7. In detail, the hook 536 extending upward passes through the hook through hole 522 formed on the outer circumferential surface of each lower portion of the lower cover 520, and finally to the lower end of the coupling groove 512 formed on the outer circumferential surface of each upper portion of the upper cover 510. Is fitted. To this end, the upper end of the hook 536 forms a locking end 537 protruding inward. On the other hand, as described above, the coupling groove 512 of the upper cover 510 is recessed inwardly when viewed from the second coupling groove 513c and the hook coupling groove 513c of the lower side protruding relatively outward. Since the stepped portion 513b is formed between the first coupling grooves 513a at the upper end, the locking end 537 of the upper end of the hook 536 may be stably fitted into the stepped portion 513b. Preferably, the locking end 537 is configured to form a predetermined inclined 537a, and the stepped portion 513b of approximately intermediate height forming the coupling groove 510 formed on the outer periphery of each part of the upper cover 510 forms an inclined surface. In this case, it may be configured to correspond thereto.

In addition, for example, the terminal insertion groove 538 is formed at one outer circumferential surface of the base 530 so that the feed terminal 426 extending downward from one side of the second elastic member 430 may be electrically connected to an external electrode. It may be provided so that the feed terminal 426 can be fitted. In addition, although not illustrated in the drawings, a filter (for example, an IR filter) for controlling the amount of light by blocking a part of incident light entering through the lens to the hollow area of the base 530 is disposed, and the base 530 is disposed. At the bottom, an image sensor is formed.

In addition, the case member 500 of the present invention includes a case guide 540 coupled to cover the upper surface of the cover 502 (PORON guide). The case guide 540 also has a substantially quadrangular shape when viewed in plan view, and each of the case guides 540 is a fixed end 542 extending downward, and the coupling is formed on the outer circumferential surface of each of the upper cover 510 as shown in FIG. 7. It is configured to be inserted into the case guide coupling groove 513a at the top of the groove 512. The case guide 540, for example, blocks a magnetic field generated by a magnet formed in another module in a mobile communication device in which the autofocus lens actuator 100 of the present invention is actually mounted, thereby preventing problems such as poor focus due to the magnetic field. It is to solve. In addition, the case guide 540 is for correcting the gap between the components constituting the lens actuator 100 of the present invention, preventing the inflow of foreign substances, and improving shock absorption and light shielding, for example, in Japan. It can be made of high-density, extremely high-density, uniform cell structure, PORON®, produced by Rogers-INOAC, a joint venture of INOAC and Rogers of the United States. The case guide 540 is only mounted on the upper surface of the upper cover 510 and is not shaped to surround the side of the upper cover 510, thereby preventing the size of the lens actuator 100 from being increased by the case guide 540. can do.

In particular, according to the present invention, the adhesive layer 600 is applied along the outer circumferential surfaces of the upper cover 510 and the lower cover 520 constituting the outline of the lens actuator 100 in the assembled state (see FIG. 6). Although the adhesive layer 600 is only applied to the outer circumferential surface in the drawing, when the adhesive is applied to the side of the assembled lens actuator 100, between the upper cover 510 and the lower cover 520, the lower cover 520. The adhesive may penetrate between the bottom of the bottom surface and the top surface of the base 530, as well as the area between the parts of the drive member 300 accommodated inside the case member 500 and exposed to the outside (see FIG. 9). ).

In this case, the material constituting the adhesive layer 600 is a curable material, and is a material selected from among a photocurable, room temperature curable, and thermosetting type. Specifically, it may include an epoxy resin, urethane resin, acrylic resin, silicone resin, rubber resin or ceramic adhesive, waterproofing agent or electromagnetic wave shielding agent, and suitable thickness (for example, 10 ~ 100 ㎛ by spray method, screening printing technique) ), The size of the lens actuator 100 does not substantially increase. As the adhesive layer 600 is formed, foreign matters generated from the outside can be prevented from flowing into the empty spaces between components, and electromagnetic waves generated from adjacent electronic components mounted on the mobile communication device together with the lens actuator 100. Can be blocked.

Subsequently, the process of manufacturing the lens actuator according to the present invention will be briefly described with reference to FIG. The process of assembling the lens actuator is largely a coil assembly assembly process (S810) / cover assembly assembly process (S812), a process of continuously assembling the coil assembly and the cover assembly to the base (S820, S830), and the process of mounting the peripheral accessory parts. (S840 and S850) and a process of applying an adhesive to the side of the lens actuator (S860). First, the driving coil 340 is seated on the upper surface of the flange 224 formed on the outer circumferential surface of the cylindrical carrier 220, and the coil assembly (coil is fastened by fastening the second elastic member 420 to the lower end of the carrier 220. Assembly) (S810). In this case, the inner upper end of the second elastic member 420 is fixed to the lower end of the carrier 220 by bonding or heat-caking. Independent of the process of assembling the coil assembly, the first elastic member 410, the first yoke 320, the magnet 310 and the second yoke 330 to the inner circumferential surface of the upper cover 510 having a substantially quadrangular shape And sequentially mount the lower cover 520 at the lower end of the second yoke 340, and then assembled the cover assembly (cover assembly) by fastening the upper cover 510 and the lower cover 520 (S812). ).

Subsequently, a coil assembly-base assembly is formed by mounting a coil assembly including a carrier 220, a driving coil 340, and a second elastic member 420 on an upper surface of the base 530 (S820). At this time, the feed terminal 426 extending from the side of the second elastic member 420 is forcibly fitted into the terminal insertion groove 538 formed on the side of the base 530, so that the second elastic member 420 is the base It may be seated on an upper surface of the 530.

Subsequently, the cover assembly of the upper cover 510-lower cover 520 in which the first elastic member 410, the first yoke 320, the magnet 310, and the second yoke 330 are sequentially mounted. 7 is combined with the base 530 in the same manner as described in FIG. 7 to form an assembly of the cover-base (S830). In this case, the lower end of the inner circumference of the first elastic member 410 may be coupled to the upper surface of the carrier 220 by a method such as heat-coking or bonding so that the first elastic member 410 may be stably positioned. According to this process, the outer side of the first elastic member 410 is tightly fixed between the first yoke 320 and the upper cover 510, the outer side of the second elastic member 420 is also the lower cover 520 and The base 530 is in close contact and fixed.

Subsequently, the guide ring 430 is mounted on the upper surface of the first elastic member 410, so that the guide ring 430 is fixed to the upper inner circumferential surface of the upper cover 510 so that the guide ring 430 can be stably mounted. It may be combined (S840). Subsequently, the case guide 540 is mounted on the top of the upper cover 510 in which the guide ring 430 is formed.

An adhesive layer having an appropriate thickness is applied and formed on the outer circumferential surface of the assembled lens actuator before the lens unit 210 is finally accommodated in the carrier 220 by, for example, screwing means to the assembled lens actuator (see FIG. S860). Since the adhesive layer forming step S860 may be optionally performed after the base-cover assembly assembling step S830, the adhesive layer forming step S860 is not necessarily performed after the guide ring mounting step S840 and / or the case guide mounting step S850. . As a method for applying the adhesive layer to the outside of the lens actuator, a syringe, a screening printing method, or a spray method may be used. Preferably, screening printing techniques can be used to improve the economics of the process. As the material forming the adhesive layer, a curable material may be used. After forming the adhesive layer (S860), a process of assembling the lens unit 210 to the carrier 220 may be performed.

Through such a method, the adhesive may penetrate between the outer circumferential surface of the lens actuator 100 and various parts opened to the outside. For example, Figure 9 is a photograph of the lens actuator after the coating on the outside of the lens actuator using an epoxy resin according to the present invention. As well as the outer circumferential surfaces of the covers 510 and 520 forming the lens actuator of the present invention, between the bottom surface of the case guide 530 and the top surface of the upper cover 510, the bottom surface of the first yoke 320 and the magnet 310. ) Between the upper surface, between the bottom surface of the magnet 310 and the upper surface of the second yoke 330, the gap between the upper cover 510 and the lower cover 520, the lower cover 520 and the base 530 is coupled The gap between the gap, the outer peripheral surface of the upper cover 510 and the inner peripheral surface of the hook 536 of the base 530, the inner peripheral surface of the upper cover 510 and the outer peripheral surface of the magnet 310 / yoke (320, 330), etc. The penetration was confirmed (indicated by the red arrow in the figure). Accordingly, as a result of performing a dust test on the lens actuator to which the adhesive layer is applied, it may be confirmed that foreign matter did not flow into the lens actuator (see FIG. 10). As a result, when the lens actuator of the present invention is used, dust does not flow into the image capturing region, and thus focusing error does not occur, thereby improving image quality. In addition, since the actual size of the lens actuator does not increase, there is an advantage that can meet the trend of miniaturization of the mobile communication terminal.

In the above, a preferred embodiment of the present invention has been described, but this is only presented to help those skilled in the art to which the present invention pertains, and the present invention is not limited thereto. Rather, it will be apparent to those skilled in the art that various modifications and variations can be made easily from the above-described embodiments and the accompanying drawings. However, it will be more apparent from the following claims that such modifications and variations fall within the scope of the present invention without departing from the spirit of the present invention.

100: lens actuator 200: lens unit (lens module)
210: lens unit 220: carrier
300: driving unit 310: magnet
320, 330: yoke 340: drive coil
410, 420: elastic member 430: guide ring
500: case member 502: cover
510: upper cover 520: lower cover
530: base 600: adhesive layer

Claims (7)

A lens actuator for image capturing a camera module adopted in a mobile communication device,
A lens unit accommodating a lens unit for photographing a subject and movable in an optical axis direction;
A driving unit for moving the lens unit in the optical axis direction by a driving force caused by the interaction of the magnet and the driving coil disposed around the lens unit;
A case member accommodating the lens portion and the driving portion, the case member including a cover coupled to an outer periphery of the driving portion, and a base supporting a lower end of the lens portion; And
Lens actuator for image pickup comprising an adhesive layer applied along at least the outer peripheral surface of the cover.
The method of claim 1,
The material constituting the adhesive layer is a lens actuator for image pickup, characterized in that the curable material.
The method of claim 2,
The material constituting the adhesive layer is an image lens lens actuator comprising an epoxy resin, urethane resin, acrylic resin, silicone resin, rubber resin or ceramic adhesive, waterproofing agent or electromagnetic wave blocking agent.
4. The method according to any one of claims 1 to 3,
The drive unit is wound around the magnet unit disposed around the lens unit, a first yoke disposed above the magnet, a second yoke disposed below the magnet, and an outer circumferential surface of the lens unit and interlocked with the lens unit. And a coil disposed to face the inner circumferential surface of the second yoke.
The method according to any one of claims 1 to 3,
And the lens unit comprises a cylindrical carrier and a lens unit assembled in the carrier.
Winding the drive coil to the outer circumferential surface of the carrier and fastening a second elastic member to the bottom of the carrier to form a coil assembly;
Receiving a first elastic member, yoke, and magnet on an inner surface of the upper cover, and then combining the upper cover and the lower cover to form a cover assembly;
After placing the coil assembly on an upper surface of a base, engaging the cover assembly with the base; And
And applying an adhesive layer to the outside of the lens actuator coupled to the cover assembly and the base.
The method of claim 6,
The adhesive layer is a method of manufacturing a lens actuator for image pickup, characterized in that the coating using a curable material.

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