KR20070084961A - Camera module package and vcm-type actuator for the same - Google Patents

Abstract

A camera module package and a VCM(Voice Coil Motor) type actuator used in the same are provided to improve falling reliability and have excellent magnetic efficiency and driving sensibility performance. A bobbin(211) is combined with a lens part(100), and a guide hole is formed in the bobbin(211). A plurality of magnets(212) is attached to the bobbin(211). A coil-yoke assembly(220) is installed to be separated from a bobbin-magnet assembly(210) to the outside. A holder(223) is combined to an outer circumference surface of the coil-yoke assembly(220). A lower case(224) is combined with the holder(223), and a guide shaft inserted into the guide hole formed in the bobbin(211) is formed in the lower case(224). An image sensor module(300) is combined to a lower part of the lower case(224). The image sensor module(300) picks up an image passing through the lens part(100).

Description

CAMERA MODULE PACKAGE AND VCM-TYPE ACTUATOR FOR THE SAME}

1A is a perspective view of an actuator used in a camera module package according to the prior art.

Figure 1b is a perspective view of a leaf spring used in the camera module package according to the prior art.

2 is a cross-sectional view of a camera module package including an actuator according to the prior art.

3 is an exploded perspective view of a camera module package including an actuator according to the present invention.

4 is a detailed exploded perspective view of a camera module package including an actuator according to the present invention.

Fig. 5 is a perspective view showing a position in a coupled state of a magnet, a coil, and a yoke of the mobile actuator according to Fig. 4.

6 is an operational state diagram of a camera module package including an actuator according to the present invention;

Figure 6a shows a state before the current is applied to the coil of the fixed portion of the actuator,

Figure 6b shows a state in which a current is applied to the coil of the fixed portion of the actuator.

<Description of Major Symbols in Drawing>

100: lens portion (lens barrel) 200: actuator

210: drive unit (bobbin-magnet assembly) 211: bobbin

211a: Guide hole 211b: Magnet seating part

212: magnet 220: fixed part

221 coil 222 yoke

223 holder 224 lower case

224a: guide shaft 300: image sensor module

The present invention relates to an actuator of a VCM type capable of fine driving and a camera module package using the same, and in particular, a VCM applicable to a general or mobile camera module, an optical module, and a measurement equipment requiring fine driving such as focus adjustment. It relates to an actuator of a type and a camera module package using the same.

Recently, due to the rapid development of information and communication technology, the improvement of data communication speed and the increase of data communication amount are realized, and the imaging devices such as CCD image sensor and CMOS image sensor are mounted on mobile electronic devices such as mobile phones and laptops. It is spread | distributing and these can transmit the image data image | photographed by the camera module besides the text data by real-time process.

In addition, as the camera module package for mobile devices has become high pixels and high performance, rapid technological developments are being carried out to have performance similar to those of general high-end digital cameras, and in particular, auto focusing technology is implemented in mobile size. Attempts have been made at various angles, and the mainstream of them is the use of an actuator of a voice coil motor (VCM) type.

As shown in FIG. 1A, the actuator of the VCM type has a lens-mounted driving unit (not shown) by an electromagnetic force generated by the interaction of a magnetic field generated by the magnet 11 and an electric field generated by the coil 12. Autofocusing is performed by driving Reference numeral 13 corresponds to a yoke.

On the other hand, the most essential part of the components of the actuator of the VCM type is a spring provided with a restoring force for supporting the driving unit and adjusting the focusing driving degree of the driving unit. In general, the invention disclosed in Japanese Laid-Open Patent Publication No. 2004-280031, etc., as well as a commercially available product, supports the driving unit by using a plate spring as shown in FIG. The driving degree is being adjusted.

In order to improve the sensitivity of the driving unit in the conventional mobile actuator to secure sufficient performance, the leaf spring had to be manufactured to a thickness of 0.05 mm or less with a complicated shape as shown in FIG. Therefore, the leaf spring having such a complicated shape and thin thickness is not only difficult to manufacture, but also has a problem in that the production cost increases.

In addition, in order to apply the current to the coil 12 through the leaf spring, a process of connecting and assembling one end of the coil 12 to the leaf spring is required. Such an assembling process is quite cumbersome, and the work time is quite cumbersome and a lot of work time is required. It caused a problem.

In addition, the circular magnet 11 used in the conventional mobile actuator has a problem that the unit cost is high and difficult to manufacture, and the magnetic efficiency is lowered due to its geometric characteristics.

In particular, due to the thin thickness of the plate spring of 0.05 mm or less, the spring bends at the time of the drop, causing a fatal problem in the drop reliability.

On the other hand, an actuator of the VCM type for driving up and down two steps without using the above-described leaf spring has been developed, and a camera module package using such an actuator is disclosed in Korean Laid-Open Patent Publication No. 2005-0095423. Figure 2 shows the technique disclosed in the Republic of Korea Patent Publication No. 2005-0095423.

However, as shown in FIG. 2, in the technique disclosed in the above publication, the first magnetic body 22 and the second magnetic body 23 are essential for the two-step implementation, that is, to attach the lens barrel 21 up and down. In addition, the size of the camera module package is inevitably increased, and the manufacturing cost increases and the manufacturing process is cumbersome. In addition, in order to move the lens barrel 21 to a position where each of the first magnetic body 22 and the second magnetic body 23 is installed, it is necessary to apply a current to the coil 25 in the forward and reverse directions. In addition to the on / off control of the need for a driver that can control the direction of the current. In addition, when a shock is received, a phenomenon occurs in which a position is reversed to an upper side or a lower side in a state in which a driving current is not applied. Meanwhile, reference numerals 24 and 26 shown in FIG. 2 correspond to magnets and yokes, respectively.

The present invention has been derived to solve the above problems, the present invention can be operated by a simple control method, the manufacturing process is simple and can reduce the manufacturing cost, as well as improve the magnetic efficiency and drop reliability An object of the present invention is to provide an actuator of a VCM type having excellent driving sensitivity and a camera module package using the same.

Camera module package according to an embodiment of the present invention for achieving the above object, the lens unit; A bobbin coupled to the lens unit and having a guide hole formed therein; A plurality of magnets attached to the bobbin; A coil-yoke assembly installed to be spaced outwardly from the bobbin and magnet assembly; A holder coupled to an outer circumferential surface of the coil-yoke assembly; A lower case coupled to the holder and having a guide shaft inserted into a guide hole formed in the bobbin; And an image sensor module coupled to a lower portion of the lower case to capture an image passing through the lens unit.

Here, the bobbin and the coil is formed in a hexahedral shape having a rectangular cross section in the horizontal direction, characterized in that each of the plurality of magnets are attached to each side of the bobbin.

In addition, the yoke of the coil-yoke assembly is attached to the outer surface of the coil.

And, the yoke is preferably composed of any one of one to three attached to each of one to three side of the coil.

On the other hand, VCM type actuator according to an embodiment of the present invention for achieving the above object is composed of a bobbin and a plurality of magnets attached to the bobbin, the drive unit movable in the vertical direction; And a coil installed in a shape spaced apart from the driving part and surrounding the driving part, a yoke attached to the coil, and a holder coupled to an outer circumferential surface of the coil-yoke assembly, the fixed part being supported to drive the driving part. Include the government.

In addition, the bobbin of the drive unit is formed with a guide hole, characterized in that it further comprises a lower case provided with a guide shaft coupled to the lower portion of the fixed portion and inserted into the guide hole formed in the bobbin of the drive unit.

Here, the bobbin and the coil is formed in a hexahedral shape having a horizontal cross section of a rectangular, characterized in that each of the plurality of magnets are attached to each side of the bobbin.

And, the yoke of the fixing portion is preferably attached to the outer surface of the coil.

In addition, the yoke is preferably composed of any one of one to three is attached to each of one to three side of the coil.

The technical features and operation of the present invention will be more clearly understood by the specific embodiments described below. Therefore, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

Actuator and camera module package containing it

3 is an exploded perspective view of a camera module package including an actuator of the VCM type according to the present invention.

As shown in FIG. 3, the camera module according to the present invention includes a lens unit (lens barrel) 100 in which a plurality of lenses are mounted, and an image sensor module for capturing an image passing through the lens unit 100. 300, and an actuator 200 for moving the lens unit 100 up and down for autofocusing in the image sensor module 300.

The lens barrel 100 corresponding to the lens unit is coupled to the actuator 200, functions as a lens holder, and is typically formed of a resin such as polycarbonate, etc., and inside the actuator 200. An aperture, a condenser lens, and the like are installed on the bottom side inserted into the lens. The aperture defines a passage of light passing through the condenser lens, and the condenser lens receives light passing through the aperture to the light receiving portion of the image sensor element described later. An IR coated glass is adhered to the upper surface of the lens barrel 100, and the noise generated in the image sensor may be reduced by preventing light from being transmitted except for the visible light region.

The image sensor module 300 includes an image sensor coupled to the circuit board to receive and process light passing through the lens barrel 100 and coupled from the downward direction of the actuator 200. In general, the packaging method of an image sensor for a camera is a flip-chip (chip on flim) packaging method, a wire bonding method of a chip on board (COB) packaging method, and a chip scale package (CSP) method. Among them, a COF packaging method and a COB packaging method are widely used.

The image sensor includes a light receiving unit for receiving light received from the condensing lens of the lens barrel 100 and performing photoelectric conversion, and a signal processing unit for transmitting the signal generated by the light receiving unit as image data. A plurality of electrode pads are formed on one surface of the circuit board and attached to the circuit board, and bumps are formed on the electrode pads. For example, when the image sensor is attached in a COF flip chip packaging method, bumps and anisotropic conductive films (ACF) or non-conductive liquid polymers (NCP: non-conductive paste) protruding from the outer surface of the electrode pad may be used. Use to attach. The bump may be configured of any one of a stud type bump, an electroless bump, and an electrolytic bump. Since the stud type bump may reduce the height of the bump during flip chip pressurization, the step between ceramic leads may be improved. It is also advantageous in terms of improving the reliability of the product.

The actuator 200 includes a case for protecting the inside from an external environment as a driving unit for moving the lens barrel 100 up and down for the autofocusing operation in the image sensor module 300.

The actuator 200 according to the present invention, as shown in Figure 4 and 5, for the autofocusing operation in the image sensor module 300, the drive unit consisting of a bobbin-magnet assembly movable in the vertical direction ( 210 and a fixing part 220 to which a coil-yoke assembly and a holder are coupled to drive the driving part 210 formed of the bobbin-magnet assembly.

4 is a detailed exploded perspective view of a camera module package including a VCM type actuator according to an embodiment of the present invention, and FIG. 5 is a view illustrating a combination of a magnet, a coil, and a yoke of a mobile actuator according to FIG. 4. It is a perspective view showing a position.

The bobbin-magnet assembly constituting the drive unit 210 includes a bobbin 211 having a guide hole 211a and a plurality of magnets 212 attached to an outer surface of the bobbin 211, and thus a coil-yoke assembly. It can be moved up and down by the operation of the fixing part 220 composed of the back. Two or more guide holes 211a are preferably formed in a symmetrical direction, and a bobbin-magnet assembly in which the guide shaft 224a to be described later is inserted into the guide hole 211a to which the lens unit 100 is coupled. The 210 can slide stably. On the other hand, the configuration of the guide hole 211a and the guide shaft 224a corresponds to a guiding means for moving the bobbin 211 stably up and down without shaking, but is not necessarily limited thereto.

As shown in FIG. 4, the bobbin 211 has a hexahedron shape having a rectangular cross section in a horizontal direction, and four magnets 212 are mounted on four sides of the hexahedron to be seated and attached. The part 211b is formed. A through hole for coupling with the lens unit 100 is formed at the central portion of the bobbin 211. Such bobbins slide up and down by an electromagnetic force generated by the interaction of the coil 14 and the magnet 13 described later.

The magnet 212 is attached to the mounting portion 211b formed on the outer surface of the bobbin 211 as described above. A square magnet may be used as the magnet 212, and as shown in FIG. 5, a magnetic field is generated by taking a bipolarized shape in the transverse and longitudinal directions, respectively.

The bobbin-magnet assembly includes a fixing part 220 having a size larger than that of the bobbin-magnet assembly 210 so that the bobbin-magnet assembly is spaced apart from the driving unit 210 corresponding to the bobbin-magnet assembly. It is positioned in the shape surrounding 210.

The fixing part 220 includes a coil 221, a yoke 222 attached to the coil 221, and a holder 223 coupled to an outer circumferential surface of the coil-yoke assembly from the inside.

The coil 221 serves to generate an electric field by a current applied from the outside. The magnetic field generated by the magnet 212 is transmitted to the coil 221, and the bobbin-magnet assembly 210 may be driven by the electromagnetic force generated by the interaction of the magnetic field and the electric field. That is, the coil 221 through which current passes in the magnetic field space formed around the magnet 212 generates a predetermined force, and this force causes the bobbin-magnet assembly 210 on which the lens unit 100 is mounted. It becomes the driving force to drive up and down.

When the yoke 222 does not apply a current to the coil 221, the magnetic force acts by the yoke 222 so that the driving unit 210 is fixed to the lower reference position to act as a 'magnetic spring'. Will be

In addition, the magnetic field generated by the magnet 212 is concentrated on the coil 221 that is installed to be spaced apart from the magnet 212 by a predetermined distance, thereby increasing the magnetic efficiency and preventing the optical axis from twisting. It also serves as a side pressure guide that maintains a constant space between the drive portion 210 of the bobbin-magnet assembly and the fixing portion 220 including the coil-yoke assembly.

In addition, in the prior art, the first magnetic body 22 and the second magnetic body 23 are essentially required as shown in FIG. 2 in order to attach the lens barrel 21 to the two-step implementation, that is, the upper and lower positions. In the present invention, the yoke 222 attached to the fixing part 220 is first and second in the prior art, although the manufacturing cost increases and the manufacturing process is cumbersome. It acts as a magnetic material and yoke does not need to be installed inside the magnet as in the prior art. As such, the yoke does not need to be installed inside the magnet, which has advantages in manufacturing process and cost reduction.

Furthermore, in the prior art illustrated in FIG. 2, whether to apply a current to the coil to move the lens barrel 21 to a position corresponding to the position of the first magnetic body 22 and the second magnetic body 23, respectively. In addition, a separate driver is needed to redirect the current through the coil. However, in the present invention, when a current is applied to the coil 221, the driving unit moves upwards, and when no current is applied, an attraction force by the yoke 222 acts to lower the reference to the driving unit 210. Since it can be moved in two steps by being fixed in position, there is an advantage of not requiring a driver to control the direction of a separate current.

The yoke 12 has a polygonal shape corresponding to the shape of the holder 11, and is formed of iron (Fe), cold rolled steel (SPCC), nickel (Ni), or the like, which has excellent magnetic permeability. desirable.

Meanwhile, the yoke 222 may be attached to the inner side or the outer side of the coil 221. However, when the yoke 222 is attached to the inner surface of the coil 221, the downward force may be excessively large, so that control as a 'magnetic spring' may be difficult, so the yoke 222 may be It is preferable to attach to the outer surface of the coil 221.

In addition, the yoke 222 may be installed one at each side of the coil 221. However, for example, when the yokes 222 are installed on all four sides of the coil 221, the manpower acting downward by the yokes 222 may be excessively large, and thus control as a 'magnetic spring' may be difficult. have. Therefore, the yoke 222 is preferably composed of any number of one to three are attached to one to three sides of the coil 221, respectively.

The holder 223 coupled to the outer circumferential surface of the coil-yoke assembly is for holding and supporting the coil-yoke assembly. If the yoke 222 is attached to the outer surface of the coil 221, the holder is mounted. Concave grooves corresponding to the shape and number of the yoke 222 are formed on the inner surface of the 223.

As illustrated in FIG. 4, the holder 223 has a rectangular parallelepiped shape having a predetermined space therein and an upper and lower surface thereof being open. The bobbin-magnet assembly and the coil-yoke assembly are accommodated in the holder 223. In addition, a lower case 224 may be further included below the fixing part 220.

Two or more guide shafts 224a are formed in the lower case 224, and the guide shafts 224a are inserted into the guide holes 211a formed in the bobbin 211 of the driving unit 210 to the driving unit 210. The bobbin-magnet assembly is slid up and down stably.

Operation of the Camera Module Package

Hereinafter, the operation of the camera module package by the actuator according to the present invention will be described.

6 is an operation state diagram of a camera module package including an actuator according to the present invention. FIG. 6A illustrates a state before a current is applied to the coil 221 of the fixing unit 220 of the actuator 200. FIG. A current is applied to the coil 221 of the fixing part 220 of the actuator 200.

As shown in FIG. 6A, when no current is applied to the actuator 200, the attraction force by the yoke 222 is in operation, and thus the driving unit 210 to which the lens unit 100 is coupled is located at a lower reference position. It is fixed. In particular, the present invention, when used as a mobile camera module with a lot of movement, unlike the prior art, since the lens unit 100 is fixed to the lower side by the yoke 222, even when no current is supplied, there is an advantage in terms of breakage reliability. have.

Next, as shown in FIG. 6B, when a current is applied to the actuator 200, a magnetic field generated by the magnet 212 is transmitted to the coil 221, which is caused by the interaction between the magnetic field and the electric field. The driving unit 210 to which the lens unit 100 is coupled is driven upward by the electromagnetic force by the electromagnetic force. That is, the coil 221 through which current passes in the magnetic field space formed around the magnet 212 generates a predetermined force, and this force drives the bobbin-magnet assembly on which the lens unit 100 is mounted up and down. It becomes the driving force to make.

As described above, according to the present invention, it is possible to perform macro focusing or the like by driving the object to be transferred, such as the lens unit, by two steps without simply controlling the current direction.

Although preferred embodiments of the present invention have been described in detail above, those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concept of the present invention as defined in the following claims also belong to the scope of the present invention.

As described above, the present invention has an excellent magnetic efficiency and drive sensitivity performance while improving the drop reliability by the yoke installed in the fixed portion.

In addition, in the present invention, when a current is applied to the coil fixed to the fixed part, the driving unit moves upward, and when no current is applied, the attraction force by the yoke acts to fix the driving unit at the lower reference position. Since the step can be moved, there is an effect that no driver is required to control the direction of a separate current.

In addition, in the present invention, in the implementation of the two-step yoke attached to the fixed part serves as the first and second magnetic material in the prior art, and yoke is not required to be installed on the inner side of the magnet as in the prior art. And it is possible to reduce the cost, it is also possible to prevent the phenomenon that the position of the driving unit is reversed due to the impact in the prior art.

After all, the present invention can be operated by a simple control method, the production process is simple and creates an effect that can reduce the manufacturing cost.

Claims (9)

A lens unit; A bobbin coupled to the lens unit and having a guide hole formed therein; A plurality of magnets attached to the bobbin; A coil-yoke assembly installed to be spaced outward from the bobbin-magnet assembly; A holder coupled to an outer circumferential surface of the coil-yoke assembly; A lower case coupled to the holder and having a guide shaft inserted into a guide hole formed in the bobbin; And An image sensor module coupled to a lower portion of the lower case and configured to capture an image passing through the lens unit; Camera module package comprising a. The method of claim 1, The bobbin and the coil is made of a hexahedral shape having a rectangular cross section in the horizontal direction, each of the plurality of magnets are camera module package, characterized in that attached to each side of the bobbin. The method of claim 2, And the yoke of the coil and yoke assembly is attached to an outer surface of the coil. The method of claim 3, The yoke is composed of any one of one to three, the camera module package, characterized in that attached to each of one to three sides of the coil. A driving part composed of a bobbin and a plurality of magnets attached to the bobbin and movable in a vertical direction; And A fixed part fixed and supported to drive the driving part, comprising a coil installed in a shape spaced apart from the driving part and surrounding the driving part, a yoke attached to the coil, and a holder coupled to an outer circumferential surface of the coil-yoke assembly; ; VCM type actuator comprising a. The method of claim 5, A guide hole is formed in the bobbin of the driving unit, And a lower case having a guide shaft coupled to a lower portion of the fixing part and inserted into a guide hole formed in the bobbin of the driving part. The method of claim 5, The bobbin and the coil is made of a hexahedral shape having a horizontal cross section of the rectangular, each of the plurality of magnets are attached to each side of the bobbin VCM type actuator. The method of claim 7, wherein The yoke of the fixing portion is VCM type actuator, characterized in that attached to the outer surface of the coil. The method of claim 8, The yoke is one of three to three VCM type actuator, characterized in that attached to each of one to three sides of the coil.

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