KR20200133703A - Lens driving apparatus and camera module including the same - Google Patents

Abstract

According to one embodiment of the present invention, a camera module includes: a housing; a carrier received in the housing and able to move in a direction of an optical axis; a frame and a lens holder received in the carrier and moved with the carrier in the direction of the optical axis; a lens barrel mounted on the lens holder; a first shaking correction driving part including a first magnet arranged on the lens holder and a first coil facing the first magnet; a second shaking correction driving part including a second magnet arranged on the lens holder and a second coil facing the second magnet; a focus adjustment driving part including a third magnet arranged on the carrier and a third coil facing the third magnet; a yoke part facing the first magnet and the second magnet in the direction of the optical axis and arranged on the carrier; a first ball member arranged between the carrier and the frame and able to move in a direction of a first axis perpendicular to the direction of the optical axis; and a second ball member arranged between the frame and the lens holder and able to move along a direction of a second axis perpendicular to the direction of the first axis, wherein the frame is arranged between the carrier and the lens holder and the carrier and the lens holder have faces directly facing each other. Therefore, the camera module has a compact size while having an image stabilizing function.

Description

Lens driving apparatus and camera module including the same

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

Recently, micro-camera modules have been employed in mobile communication terminals such as smart phones, tablet PCs, and notebook computers.

As mobile communication terminals become smaller, the image quality deteriorates because the influence on hand shake is greater during image capture. Therefore, a correction technique for hand shake is required to obtain a clear image.

When hand shake occurs during image capture, an OIS actuator applied with OIS (Optical Image Stabilization) technology can be used to compensate for hand shake. The OIS actuator can move the lens module in a direction perpendicular to the optical axis.

However, when the OIS actuator is employed, there is a problem that the size of the camera module increases.

An object according to an embodiment of the present invention is to provide a lens driving device capable of miniaturizing a size while having a shake correction function, and a camera module including the same.

The camera module according to an embodiment of the present invention includes a housing; A carrier accommodated in the housing and movable in the optical axis direction; A frame and a lens holder accommodated in the carrier and movable together with the carrier in the optical axis direction; A lens barrel mounted on the lens holder; A first shake correction driver including a first magnet disposed on the lens holder and a first coil facing the first magnet; A second shake correction driver including a second magnet disposed on the lens holder and a second coil facing the second magnet; A focus adjustment driver including a third magnet disposed on the carrier and a third coil facing the third magnet; A yoke portion facing the first magnet and the second magnet in the optical axis direction and disposed on the carrier; A first ball member disposed between the carrier and the frame and movable in a first axis direction perpendicular to the optical axis direction; And a second ball member disposed between the frame and the lens holder and movable along a second axial direction perpendicular to the first axial direction, wherein the frame is disposed between the carrier and the lens holder, , The carrier and the lens holder may have surfaces that directly face each other.

A lens driving apparatus and a camera module including the same according to an exemplary embodiment of the present invention may have a shake correction function and may be miniaturized.

1 is a perspective view of a camera module according to an embodiment of the present invention,
2 is a schematic exploded perspective view of a camera module according to an embodiment of the present invention,
3 is a cross-sectional view of A-A' of FIG. 1,
4 is a schematic enlarged view of part B of FIG. 3,
5 is a partially exploded perspective view of a camera module according to an embodiment of the present invention,
6 is a schematic perspective view showing a modified example of FIG. 5,
7 and 8 are exploded perspective views of a shake correction unit according to an embodiment of the present invention,
9 is a conceptual diagram illustrating the degrees of freedom of an object,
10 is a combined perspective view of a shake correction unit according to an embodiment of the present invention,
FIG. 11A is a perspective view taken along CC′ of FIG. 10,
11B is a perspective view showing a state in which the shake correction unit is moved by a driving force generated in the X-axis direction,
12A is a perspective view of a portion DD′ of FIG. 10 cut away,
12B is a perspective view showing a state in which the shake correction unit is moved by the driving force generated in the Y-axis direction,
13 is a plan view showing a state in which a first ball member and a third ball member are disposed in a carrier of the present invention,
14 is a plan view showing a state in which a second ball member is disposed in a frame of the present invention and a third ball member is disposed in a carrier,
15A is a perspective view showing the movement of the first ball member of the present invention,
15B is a perspective view showing the movement of the second ball member of the present invention,
15C is a perspective view showing the movement of the third ball member of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. However, the spirit of the present invention is not limited to the presented embodiments.

For example, a person skilled in the art who understands the spirit of the present invention may suggest other embodiments included within the scope of the spirit of the present invention through addition, change, or deletion of components, etc. It will be said to be within the range.

The present invention relates to a lens driving device and a camera module including the same, and can be applied to portable electronic devices such as mobile communication terminals, smart phones, and tablet PCs.

The camera module is an optical device for photographing or moving pictures, and includes a lens that refracts light reflected from a subject, and a lens driving device that moves the lens to adjust focus or correct shake.

1 is a perspective view of a camera module according to an embodiment of the present invention, and FIG. 2 is a schematic exploded perspective view of a camera module according to an embodiment of the present invention.

1 and 2, the camera module 1000 according to an embodiment of the present invention includes a lens barrel 200, a lens driving device 500 for moving the lens barrel 200, and a lens barrel 200. A housing 120 and a case 110 accommodating the image sensor unit 600 and the lens barrel 200 and the lens driving device 500 for converting the incident light into an electric signal are included.

The lens barrel 200 may have a hollow cylindrical shape so that a plurality of lenses for photographing a subject can be accommodated therein, and the plurality of lenses are mounted on the lens barrel 200 along an optical axis.

The plurality of lenses are arranged as many as necessary according to the design of the lens barrel 200, and each lens has optical characteristics such as the same or different refractive index.

The lens driving device 500 is a device that moves the lens barrel 200.

For example, the lens driving device 500 may adjust the focus by moving the lens barrel 200 in the optical axis (Z axis) direction, and photographing by moving the lens barrel 200 in a direction perpendicular to the optical axis (Z axis). City shake can be corrected.

The lens driving apparatus 500 includes a focus adjustment unit 300 for adjusting a focus and a shake correction unit 400 for correcting shake.

The image sensor unit 600 is a device that converts light incident through the lens barrel 200 into an electric signal.

For example, the image sensor unit 600 may include an image sensor 610 and a printed circuit board 620 connected to the image sensor 610, and may further include an infrared filter.

The infrared filter serves to block light in the infrared region among the light incident through the lens barrel 200.

The image sensor 610 converts light incident through the lens barrel 200 into an electric signal. For example, the image sensor 610 may be a Charge Coupled Device (CCD) or a Complementary Metal-Oxide Semiconductor (CMOS).

The electric signal converted by the image sensor 610 is output as an image through the display unit of the portable electronic device.

The image sensor 610 is fixed to the printed circuit board 620 and is electrically connected to the printed circuit board 620 by wire bonding.

The lens barrel 200 and the lens driving device 500 are accommodated in the housing 120.

For example, the housing 120 has an open upper and lower portion, and the lens barrel 200 and the lens driving device 500 are accommodated in an inner space of the housing 120.

An image sensor unit 600 is disposed under the housing 120.

The case 110 is coupled to the housing 120 so as to surround the outer surface of the housing 120 and serves to protect internal components of the camera module.

In addition, the case 110 may function to shield electromagnetic waves.

For example, the case 110 may shield the electromagnetic waves so that the electromagnetic waves generated from the camera module do not affect other electronic components in the portable electronic device.

In addition, since various electronic components other than the camera module are mounted on the portable electronic device, the case 110 may shield the electromagnetic waves so that the electromagnetic waves generated from these electronic components do not affect the camera module.

The case 110 may be made of a metal material and may be grounded to a ground pad provided on the printed circuit board 620, thereby shielding electromagnetic waves.

FIG. 3 is a cross-sectional view of A-A' of FIG. 1, and FIG. 4 is a schematic enlarged view of portion B of FIG. 3.

Also, FIG. 5 is a partially exploded perspective view of a camera module according to an embodiment of the present invention.

The focus adjustment unit 300 of the lens driving apparatus 500 according to an exemplary embodiment of the present invention will be described with reference to FIGS. 3 to 5.

In the lens driving device 500 according to an embodiment of the present invention, the lens barrel 200 is moved to focus on a subject.

For example, the present invention includes a focus adjustment unit 300 for moving the lens barrel 200 in the optical axis (Z axis) direction.

The focus adjustment unit 300 includes a carrier 310 accommodating the lens barrel 200, and a focus adjustment driver for generating a driving force to move the lens barrel 200 and the carrier 310 in the optical axis (Z axis) direction. Include.

The focus adjustment driver includes a magnet 320a and a coil 330a.

The magnet 320a is mounted on the carrier 310. For example, the magnet 320a may be mounted on one surface of the carrier 310.

The coil 330a is mounted on the housing 120. For example, the coil 330a may be mounted on the housing 120 via the substrate 130. Although the coil 330a is not shown in FIG. 2, the coil 330a is fixed to the substrate 130 and disposed at a position facing the coil 452 of the shake correction unit 400.

The magnet 320a is a moving member mounted on the carrier 310 and moving in the optical axis (Z-axis) direction together with the carrier 310, and the coil 330a is a fixing member fixed to the housing 120. However, the present invention is not limited thereto, and the positions of the magnet 320a and the coil 330a may be changed.

When power is applied to the coil 330a, the carrier 310 may be moved in the optical axis (Z axis) direction due to electromagnetic influence between the magnet 320a and the coil 330a.

Since the lens barrel 200 is accommodated in the carrier 310, the lens barrel 200 is also moved in the optical axis (Z axis) direction by the movement of the carrier 310.

When the carrier 310 is moved, a rolling member 370 is disposed between the carrier 310 and the housing 120 to reduce friction between the carrier 310 and the housing 120. The rolling member 370 may have a ball shape.

The rolling members 370 are disposed on both sides of the magnet 320a.

A first yoke 350 is disposed in the housing 120. For example, the first yoke 350 is disposed to face the magnet 320a with the coil 330a interposed therebetween.

The attractive force acts in a direction perpendicular to the optical axis (Z axis) between the first yoke 350 and the magnet 320a.

Accordingly, the rolling member 370 may maintain a contact state with the carrier 310 and the housing 120 due to the attraction between the first yoke 350 and the magnet 320a.

In addition, the first yoke 350 also functions to focus the magnetic force of the magnet 320a. Accordingly, it is possible to prevent the leakage magnetic flux from occurring.

For example, the first yoke 350 and the magnet 320a form a magnetic circuit.

In this case, the length of the first yoke 350 in the optical axis (Z axis) direction is preferably longer than the length in the optical axis (Z axis) direction of the magnet 320a.

When the length in the optical axis (Z axis) direction of the first yoke 350 is shorter than the length in the optical axis (Z axis) direction of the magnet 320a, when the magnet 320a moves in the optical axis (Z axis) direction, the magnet 320a The attractive force acting so that the center faces the center of the first yoke 350 increases.

Accordingly, since the return force for the magnet 320a to return to its original position acts more strongly, the amount of current required to move the magnet 320a increases, and power consumption increases.

However, if the length in the optical axis (Z axis) direction of the first yoke 350 is longer than the length in the optical axis (Z axis) direction of the magnet 320a, the center of the magnet 320a may be directed toward the center of the first yoke 350 Since the working force is relatively small, power consumption can be relatively reduced.

Meanwhile, a second yoke 340 may be disposed between the carrier 310 and the magnet 320a.

The second yoke 340 functions to focus the magnetic force of the magnet 320a. Accordingly, it is possible to prevent the leakage magnetic flux from occurring.

For example, the second yoke 340 and the magnet 320a form a magnetic circuit.

The present invention uses a closed loop control method that senses and feeds back the position of the lens barrel 200.

Therefore, the position sensor 360 is required for closed loop control. The position sensor 360 may be a Hall sensor.

The position sensor 360 is disposed inside or outside the coil 330a, and the position sensor 360 may be mounted on the substrate 130 on which the coil 330a is mounted.

Further, the position sensor 360 may be integrally formed with a circuit element that provides a driving signal to the focus adjustment unit 300 (see FIG. 5 ). However, the present invention is not limited thereto, and the position sensor 360 and the circuit element may be provided as separate components.

When the power of the camera module is turned on, the initial position of the lens barrel 200 is detected by the position sensor 360. Then, the lens barrel 200 is moved from the sensed initial position to the initial setting position. Here, the initial position may refer to a position in the optical axis direction of the lens barrel 200 when the camera module is turned on, and the initial setting position may refer to a position at which the focus of the lens barrel 200 becomes infinite. have.

The lens barrel 200 is moved from the initial setting position to the target position by the driving signal of the circuit element.

During the focus adjustment process, the lens barrel 200 can move forward and backward in the optical axis (Z axis) direction (ie, it can move in both directions).

Meanwhile, a magnet 320b and a coil 330b may be additionally provided to secure a sufficient driving force during focus adjustment.

If the area on which the magnet is mounted is decreased according to the trend of slimming of the camera module, the size of the magnet decreases, and thus, sufficient driving force required for focus adjustment may not be secured.

However, in the present invention, magnets 320a and 320b are attached to different surfaces of the carrier 310, respectively, and coils 330a and 330a, respectively, on different surfaces of the housing 120 so as to face each magnet 320a and 320b. By providing 330b), even if the camera module is slimmed, sufficient driving force for focus adjustment can be secured.

6 is a schematic perspective view showing a modified example of a focus adjustment unit in a lens driving apparatus according to an embodiment of the present invention.

Referring to FIG. 6, in a modified example of the present invention, one of the plurality of magnets 320a and 320b mounted on different surfaces of the carrier 310 faces the coil 330a, and the other one 320b ) Faces the position sensor 360.

For example, one of the plurality of magnets 320a and 320b functions as a driving magnet, and the other one 320b functions as a sensing magnet.

In this case, since the coil 330a and the position sensor 360 are spaced apart from each other on different surfaces of the housing 120, there is a spatial margin on the surface on which the coil 330a is mounted. Accordingly, it is possible to increase the number of windings of the coil 330a, thereby improving driving power.

In addition, since the coil 330a and the position sensor 360 are spaced apart from each other on different surfaces of the housing 120, it is possible to minimize the electric field of the coil 330a from affecting the position sensor 360. Accordingly, it is possible to improve the sensing accuracy of the position sensor 360.

7 and 8 are exploded perspective views of a shake correction unit according to an embodiment of the present invention.

The shake correction unit 400 is used to compensate for blurring of an image or shaking of a moving picture due to factors such as hand shake of a user during image capture or video capture.

For example, the shake correction unit 400 compensates the shake by applying a relative displacement corresponding to the shake to the lens barrel 200 when shaking occurs during image capture due to the shaking of a user's hand.

For example, the shake correction unit 400 corrects the shake by moving the lens barrel 200 in a direction perpendicular to the optical axis (Z axis).

7 and 8, the shake correction unit 400 is a shake that generates a driving force to move a guide member that guides the movement of the lens barrel 200 and a guide member in a direction perpendicular to the optical axis (Z axis). It includes a correction drive.

The guide member includes a frame 410 and a lens holder 420. The frame 410 and the lens holder 420 are inserted into the carrier 310 and disposed in the optical axis (Z axis) direction, and function to guide the movement of the lens barrel 200.

The frame 410 and the lens holder 420 have a space into which the lens barrel 200 can be inserted. The lens barrel 200 is fixed to the lens holder 420 (see FIG. 2).

The frame 410 and the lens holder 420 are moved in a direction perpendicular to the optical axis (Z axis) within the carrier 310 by the driving force generated by the shake correction driver.

The shake correction drive unit includes a first shake correction drive unit 440 and a second shake correction drive unit 450, and the first and second shake correction drive units 440 and 450 include magnets 441 and 451 and a coil 442. 452).

The first shake correction driver 440 generates a driving force in the direction of a first axis (X axis) perpendicular to the optical axis (Z axis), and the second shake correction driver 450 is perpendicular to the first axis (X axis). It generates a driving force in the direction of the second axis (Y axis).

Here, the second axis (Y axis) refers to an axis perpendicular to both the optical axis (Z axis) and the first axis (X axis).

The first shake correction drive unit 440 and the second shake correction drive unit 450 are disposed to be orthogonal to each other in a plane perpendicular to the optical axis (Z axis). For example, the magnet 441 of the first shake correction driver 440 and the magnet 451 of the second shake correction driver 450 are disposed to be perpendicular to each other in a plane perpendicular to the optical axis (Z axis).

The magnets 441 and 451 of the first and second shake correction driving units 440 and 450 are mounted on the lens holder 420, and the coils 442 and 452 facing the magnets 441 and 451, respectively, are It is mounted on the housing 120. 7 and 8 illustrate a state in which the coils 442 and 452 are disposed on the carrier 310 side for convenience of description, but referring to FIG. 2, the coils 442 and 452 refer to the substrate 130. It is mounted on the housing 120 as a medium.

The magnets 441 and 451 are moving members that move in a direction perpendicular to the optical axis (Z axis) together with the lens holder 420, and the coils 442 and 452 are fixed members fixed to the housing 120. However, the present disclosure is not limited thereto, and the positions of the magnets 441 and 451 and the coils 442 and 452 may be changed.

On the other hand, in the present invention, a plurality of ball members supporting the shake correction unit 400 are provided. The plurality of ball members serve to guide the frame 410 and the lens holder 420 in the shake correction process. In addition, it also functions to maintain the gap between the carrier 310, the frame 410, and the lens holder 420.

The plurality of ball members includes a first ball member 700 and a second ball member 800.

The first ball member 700 guides the movement of the shake correction unit 400 in the first axis (X-axis) direction, and the second ball member 800 is a second axis (Y) of the shake correction unit 400. It guides the movement in the axis) direction.

For example, when a driving force in the first axis (X axis) direction is generated, the first ball member 700 rolls in the first axis (X axis) direction. Accordingly, the first ball member 700 guides the movement of the frame 410 and the lens holder 420 in the first axis (X axis) direction.

In addition, the second ball member 800 rolls in the second axis (Y axis) direction when a driving force in the second axis (Y axis) direction is generated. Accordingly, the second ball member 800 guides the movement of the lens holder 420 in the second axis (Y-axis) direction.

The first ball member 700 includes a plurality of ball members disposed between the carrier 310 and the frame 410, and the second ball member 800 is disposed between the frame 410 and the lens holder 420 It includes a plurality of ball members.

First guide grooves (710a, 710b, 710c, 720a, 720b, 720c) accommodating the first ball member 700, respectively, on the surfaces of the carrier 310 and the frame 410 facing each other in the optical axis (Z axis) direction Is formed. The first guide groove portions 710a, 710b, 710c, 720a, 720b, 720c include a plurality of guide grooves.

The first ball member 700 is accommodated in the first guide grooves 710a, 710b, 710c, 720a, 720b, and 720c, and is fitted between the carrier 310 and the frame 410.

When the first ball member 700 is accommodated in the first guide grooves 710a, 710b, 710c, 720a, 720b, 720c, movement in the optical axis (Z axis) and the second axis (Y axis) direction is limited, and , It can be moved only in the direction of the first axis (X axis). For example, the first ball member 700 is capable of rolling only in the direction of the first axis (X axis).

To this end, the planar shape of each of the plurality of guide grooves of the first guide groove portions 710a, 710b, 710c, 720a, 720b, 720c is in the first axis (X axis) direction than the width in the second axis (Y axis) direction. The length of the furnace may be a longer rectangle.

In addition, some of the plurality of guide grooves of the first guide groove portions 710a, 710b, 710c, 720a, 720b, and 720c may have a different cross-sectional shape from the remaining guide grooves.

As an example, some of the guide grooves 710b and 720b among the plurality of guide grooves of the first guide grooves 710a, 710b, 710c, 720a, 720b, and 720c may have a generally'∪' shape in cross section, and the rest The guide grooves 710a, 710c, 720a, and 720c may have a generally'∨' shape in cross-sectional shape.

Here, the guide grooves 710b and 720b having a generally'∪' shape in cross-sectional shape are the third guide grooves 910 and 920 among the plurality of guide grooves of the first guide grooves 710a, 710b, 710c, 720a, 720b, and 720c. ) May be the guide groove farthest from (see FIGS. 7, 8 and 13).

Second guide grooves 810a, 810b, 810c, 820a, 820b, 820c accommodating the second ball member 800, respectively, on the surfaces of the frame 410 and the lens holder 420 facing each other in the optical axis (Z axis) direction ) Is formed. The second guide grooves 810a, 810b, 810c, 820a, 820b, and 820c include a plurality of guide grooves.

The second ball member 800 is accommodated in the second guide grooves 810a, 810b, 810c, 820a, 820b, and 820c, and is fitted between the frame 410 and the lens holder 420.

When the second ball member 800 is accommodated in the second guide grooves 810a, 810b, 810c, 820a, 820b, 820c, movement in the optical axis (Z axis) and the first axis (X axis) direction is restricted, and , It can be moved only in the direction of the second axis (Y axis). For example, the second ball member 800 is capable of rolling only in the second axis (Y axis) direction.

To this end, the planar shape of each of the plurality of guide grooves of the second guide grooves 810a, 810b, 810c, 820a, 820b, and 820c is in the second axis (Y axis) direction than the width in the first axis (X axis) direction. The length of the furnace may be a longer rectangle.

In addition, some of the plurality of guide grooves of the second guide groove portions 810a, 810b, 810c, 820a, 820b, and 820c may have a different cross-sectional shape from the other guide grooves.

For example, some of the guide grooves 810b and 820b among the plurality of guide grooves of the second guide grooves 810a, 810b, 810c, 820a, 820b, and 820c may have a generally'∪' shape in cross section, and the rest The guide grooves 810a, 810c, 820a, and 820c may have a generally'∨' shape in cross-sectional shape.

Here, the guide grooves 810b and 820b having a generally'∪' shape in cross section are the third guide grooves 910 and 920 among the plurality of guide grooves of the second guide grooves 810a, 810b, 810c, 820a, 820b, and 820c. ) May be the guide groove farthest from (see FIGS. 7, 8 and 14).

Meanwhile, in the present invention, a third ball member 900 for supporting the movement of the lens holder 420 between the carrier 310 and the lens holder 420 is provided.

The third ball member 900 guides both the movement of the lens holder 420 in the first axis (X axis) direction and the second axis (Y axis) direction.

For example, when a driving force in the first axis (X axis) direction is generated, the third ball member 900 rolls in the first axis (X axis) direction. Accordingly, the third ball member 900 guides the movement of the lens holder 420 in the first axis (X axis) direction.

In addition, the third ball member 900 rolls in the second axis (Y axis) direction when the driving force in the second axis (Y axis) direction is generated. Accordingly, the third ball member 900 guides the movement of the lens holder 420 in the second axis (Y-axis) direction.

Meanwhile, the second ball member 800 and the third ball member 900 contact and support the lens holder 420. Here, the second ball member 800 and the third ball member 900 are positioned on different planes (see FIGS. 8 and 11A to 12B ).

The lens holder 420 is provided with magnets 441 and 451 of the first and second shake correction driving units 440 and 450, and the second ball member 800 and the second ball member 800 are provided on both sides of the magnets 441 and 451, respectively. The third ball member 900 is positioned (see FIG. 8).

That is, each of the magnets 441 and 451 of the first and second shake correction driving units 440 and 450 is positioned between ball members disposed on different planes.

Third guide grooves 910 and 920 for accommodating the third ball member 900 are formed on surfaces of the carrier 310 and the lens holder 420 facing each other in the optical axis (Z axis) direction.

The third ball member 900 is accommodated in the third guide grooves 910 and 920 and is fitted between the carrier 310 and the lens holder 420.

When the third ball member 900 is accommodated in the third guide grooves 910 and 920, movement in the optical axis (Z axis) direction is limited, and the first axis (X axis) and the second axis (Y axis) You can roll in the direction.

To this end, the planar shape of the third guide groove portions 910 and 920 may be circular. Therefore, the planar shape of the third guide grooves 910 and 920, the first guide grooves 710a, 710b, 710c, 720a, 720b, 720c, and the second guide grooves 810a, 810b, 810c, 820a, 820b, 820c) The planar shapes of are different.

The first ball member 700 is capable of rolling in the first axis (X-axis) direction, the second ball member 800 is capable of rolling in the second axis (Y-axis) direction, and the third ball member 900 ) Is capable of rolling in the direction of the first axis (X axis) and the second axis (Y axis).

Accordingly, the plurality of ball members supporting the shake correction unit 400 of the present invention differ in degrees of freedom.

Here, referring to FIG. 9, the degree of freedom may mean the number of independent variables required to represent the motion state of an object in a 3D coordinate system.

In general, an object has 6 degrees of freedom in a 3D coordinate system. The movement of an object can be expressed by a three-direction Cartesian coordinate system and a three-direction rotational coordinate system.

For example, in a 3D coordinate system, an object may perform translational movement along each axis (X axis, Y axis, Z axis), and may rotate based on each axis (X axis, Y axis, Z axis).

In the present specification, the meaning of the degree of freedom means that when power is applied to the shake correction unit 400 and the shake correction unit 400 is moved by a driving force generated in a direction perpendicular to the optical axis (Z axis), the first ball member ( 700), it may mean the number of independent variables required to represent the movements of the second ball member 800 and the third ball member 900.

For example, by the driving force generated in a direction perpendicular to the optical axis (Z axis), the third ball member 900 rolls along two axes (the first axis (X axis) and the second axis (Y axis)). It is possible (refer to FIG. 15C), and the first ball member 700 and the second ball member 800 are capable of rolling motion along one axis (the first axis (X axis) or the second axis (Y axis)). (See FIGS. 15A and 15B).

Accordingly, the degree of freedom of the third ball member 800 is greater than that of the first ball member 700 and the second ball member 800.

10 to 12B, the movement of the first ball member 700, the second ball member 800, and the third ball member 900 by the driving force generated in a direction perpendicular to the optical axis (Z axis) Explain.

As shown in FIG. 11B, when the driving force Fx is generated in the first axis (X-axis) direction, the frame 410 and the lens holder 420 move together in the first axis (X-axis) direction.

Here, the first ball member 700 and the third ball member 900 roll along the first axis (X axis). At this time, the movement of the second ball member 800 is limited.

In addition, as shown in FIG. 12B, when the driving force Fy is generated in the second axis (Y-axis) direction, the lens holder 420 moves in the second axis (Y-axis) direction.

Here, the second ball member 800 and the third ball member 900 roll along the second axis (Y axis). At this time, the movement of the first ball member 700 is limited.

In this way, by limiting the movement of some ball members during the shake correction process, it is possible to prevent the frame 410 and the lens holder 420 from being rotated about the optical axis (Z axis).

Since the shake of the camera module occurs quickly enough to reach tens of Hz per second, the shake correction unit 400 is continuously moved along the first axis (X axis) and the second axis (Y axis). Therefore, since the driving force generated in the direction of the first axis (X axis) and the second axis (Y axis) is hard to always be applied to the center of the shake correction unit 400, the shake correction unit 400 is There is a risk of rotation around the optical axis (Z axis).

For example, when all the ball members are configured to be able to roll in the first axis (X axis) and the second axis (Y axis), the shake correction unit 400 will be rotated around the optical axis (Z axis). There is a concern, which causes the picture quality to deteriorate.

However, according to the present invention, by limiting the movement of some ball members during the shake correction process, it is possible to prevent the shake correction unit 400 from being rotated about the optical axis (Z axis) with a mechanical structure.

On the other hand, if the ball members rolling along the first axis (X axis) are referred to as a first ball member, and the ball members rolling along the second axis (Y axis) are referred to as the second ball member, the carrier 310 The ball member 900 (the third ball member described above) disposed between the lens holder 420 and the lens holder 420 functions as a first ball member when the shake correction unit 400 moves in the first axis (X axis) direction, and shakes. When the correction unit 400 moves in the second axis (Y axis) direction, it functions as a second ball member.

Therefore, in this case, the first ball member and the second ball member have ball members shared with each other.

The lens driving apparatus 500 of the present invention uses a closed loop control method that senses and feeds back the position of the lens barrel 200 during the shake correction process.

Accordingly, position sensors 443 and 453 for closed loop control are provided, and the position sensors 443 and 453 are inside the coils 442 and 452 of the first and second shake correction driving units 440 and 450. May be disposed (see Figs. 8 and 10).

The position sensors 443 and 453 may be Hall sensors, and the position sensors 443 and 453 are the lens barrel 200 through the magnets 441 and 451 of the first and second shake correction driving units 440 and 450. Can detect the location of.

Meanwhile, in the present invention, a yoke portion 380 is provided so that the shake correction unit 400 and a plurality of ball members maintain a contact state.

The yoke portion 380 is fixed to the carrier 310 and faces the magnets 441 and 451 of the first and second shake correction driving units 440 and 450 in the optical axis (Z axis) direction.

Accordingly, an attractive force is generated between the yoke portion 380 and the magnets 441 and 451 in the optical axis (Z axis) direction.

Since the shake correction unit 400 is pressed in the direction toward the yoke part 380 by the attraction between the yoke part 380 and the magnets 441 and 451, the frame 410 and the lens of the shake correction unit 400 The holder 420 may maintain a contact state with a plurality of ball members.

For example, by the attractive force between the yoke portion 380 and the magnets 441 and 451, the lens holder 420 is pressed toward the frame 410, and accordingly, the frame 410 moves the carrier 310 Is pressed against.

The yoke portion 380 includes a first yoke portion 380a and a second yoke portion 380b, and is a material capable of generating attractive force between the magnets 441 and 451. For example, the yoke portion 380 is provided with a magnetic material.

The first yoke part 380a faces the magnet 441 of the first shake correction drive part 440 in the optical axis (Z-axis) direction, and the second yoke part 380b is a magnet of the second shake correction drive part 450 Face 451 in the direction of the optical axis (Z axis).

The length in the direction perpendicular to the optical axis (Z axis) of the first yoke portion 380a and the second yoke portion 380b corresponds to the length in the direction perpendicular to the optical axis (Z axis) of the magnets 441 and 451 It can be small. In this case, when the magnets 441 and 451 move in a direction perpendicular to the optical axis (Z axis), a return force that attempts to return to the original position by the attractive force with the yoke portion 380 acts more strongly.

In the shake correction process, it is necessary to continuously move the lens barrel 200 along the first axis (X axis) and the second axis (Y axis) instantly in response to the user's hand shake.

As an example, since the camera module shakes due to the user's hand shake, etc., it occurs quickly enough to reach tens of Hz per second, so that only the electromagnetic force between the magnets 441 and 451 and the coils 442 and 452 corresponds to the shaking of the camera module. It can be difficult to make vibrations.

Therefore, by using the return force acting between the magnets 441 and 451 and the yoke portion 380 and the electromagnetic force between the magnets 441 and 451 and the coils 442 and 452 together, the lens barrel 200 is It can be moved to the first axis (X axis) and the second axis (Y axis).

Accordingly, it is possible to continuously move the lens barrel 200 in response to shaking, and it may be more advantageous in reducing power consumption.

When the camera module is powered on, the initial position of the lens barrel 200 (position in the direction perpendicular to the optical axis (Z axis)) is detected by the position sensors 443 and 453. Then, the lens barrel 200 is moved from the sensed initial position to the set position.

Here, the setting position may mean the center of the movable range in the direction of the first axis (X-axis) and the center of the movable range in the direction of the second axis (Y-axis). Mechanically, it may mean the center in the first axis (X axis) direction and the center in the second axis (Y axis) direction of the carrier 310 in which the shake correction unit 400 is accommodated.

When shaking does not occur in the camera module, it is necessary to fix the lens barrel 200 so that it does not move in the first axis (X axis) and the second axis (Y axis).

In the present invention, since the yoke portion 380 pulls the magnets 441 and 451 in the optical axis (Z axis) direction, if the shake correction signal is not applied, the yoke portion 380 and the magnets 441 and 451 The lens barrel 200 may be maintained in a fixed position at a predetermined position by the manpower.

However, since each component part of the camera module carries a tolerance in the manufacturing process, when the lens barrel 200 is fixed only by the attractive force between the yoke portion 380 and the magnets 441 and 451, the optical axis of the lens ( There is a fear that the Z-axis) may be distorted from the center of the image sensor 610, which may cause image quality deterioration.

In addition, it may be difficult to maintain the lens barrel 200 in a fixed state only by the attractive force between the yoke portion 380 and the magnets 441 and 451.

Therefore, in the present invention, when the camera module is turned on, the position of the lens barrel 200 (position in a direction perpendicular to the optical axis (Z axis)) is adjusted so that the lens barrel 200 is mechanically located in the center. do.

Therefore, if shaking does not occur in the camera module while the camera module is powered on, the lens barrel 200 may be configured to provide attractive force between the yoke unit 380 and the magnets 441 and 451 and the first and second shake correction driving units. By the driving force of (440, 450), it is possible to maintain a mechanically fixed state in the center.

Meanwhile, when the power of the camera module is turned off, the position of the lens barrel 200 may be fixed by the attractive force between the yoke unit 380 and the magnets 441 and 451.

In the present invention, the yoke portion 380 is provided so that the frame 410 and the lens holder 420 can maintain contact with the plurality of ball members, while the plurality of ball members, the frame 410 and the lens are A stopper 210 is provided to prevent the holder 420 from being separated from the carrier 310 (see FIG. 2 ).

The stopper 210 is coupled to the carrier 310 to cover at least a portion of the upper surface of the lens holder 420.

On the other hand, in the present invention, a guide member (frame 410 and lens holder 420) for guiding the lens barrel 200 is added in the carrier 310 to correct the shake, so the lens is driven compared to the case without the shake correction function. The size of the device 500 and the camera module 1000 is increased.

For example, based on the optical axis (Z axis) direction, the frame 410 and the lens holder 420 are sequentially disposed in the carrier 310 in the optical axis (Z axis) direction, so the frame 410 and the lens holder ( Compared to the case in which the 420 is not present, the size of the lens driving apparatus 500 and the camera module 1000 is increased.

However, the present invention can reduce the size of the lens driving apparatus 500 and the camera module 1000 while having a shake correction function.

The frame 410 and the lens holder 420 have different planar shapes. The frame 410 and the lens holder 420 may have different positions of their centers of gravity.

For example, the frame 410 may have a generally'A' shape in its planar shape, and the lens holder 420 may have a generally'ㅁ' shape in its planar shape.

Accordingly, in an area between the carrier 310 and the lens holder 420, an area in which the frame 410 is located and an area in which the frame 410 is not located exist.

As an example, when viewed from the optical axis (Z axis) direction, a region where the frame 410 and the lens holder 420 overlap each other and a region that does not overlap each other exist.

An area where the frame 410 and the lens holder 420 overlap each other in the optical axis (Z axis) direction may be an area in which the frame 410 is positioned between the carrier 310 and the lens holder 420.

A region in which the frame 410 and the lens holder 420 do not overlap each other in the optical axis (Z-axis) direction may be a region in which the frame 410 is not positioned between the carrier 310 and the lens holder 420. Accordingly, in this area, the carrier 310 and the lens holder 420 may directly face each other in the optical axis (Z axis) direction.

Here, the magnets 441 and 451 of the first and second shake correction driving units 440 and 450 and the yoke unit 380 are directly opposite the carrier 310 and the lens holder 420 in the optical axis (Z axis) direction. It is placed in the viewing area.

That is, in the frame 410, a portion corresponding to an area in which the magnets 441 and 451 of the first and second shake correction driving units 440 and 450 and the yoke unit 380 face each other in the optical axis (Z axis) direction It is an open shape.

Therefore, the frame 410 is not positioned between the magnets 441 and 451 and the yoke unit 380 of the first and second shake correction driving units 440 and 450 based on the optical axis (Z axis) direction. Accordingly, the magnets 441 and 451 may be positioned closer to the yoke portion 380.

In the present invention, by making the plane shape of the frame 410 and the lens holder 420 different, a region in which the frame 410 is not located between the carrier 310 and the lens holder 420 can be formed. By arranging the magnets 441 and 451 and the yoke portion 380, the magnets 441 and 451 may be disposed closer to the yoke portion 380.

Accordingly, the present invention can reduce the size (height in the optical axis (Z axis) direction) of the lens driving apparatus 500 and the camera module 1000 while having a shake correction function.

Here, the mounting surface of the lens holder 420 to which the magnets 441 and 451 are attached may have a shape that protrudes further toward the bottom surface of the carrier 310 compared to other portions of the lens holder 420.

Meanwhile, the third ball member 900 is disposed between the carrier 310 and the lens holder 420 to support the lens holder 420.

The magnets 441 and 451 of the first and second shake correction driving units 440 and 450 are mounted on one surface and the other surface of the lens holder 420 so as to be perpendicular to each other, and the magnets 441 and 451 and the yoke unit 380 ), since an attractive force acts between them, a pressing force biased toward the yoke portion 380 is applied to the lens holder 420.

At this time, since the frame 410 is not disposed in the area where the attractive force acts between the magnets 441 and 451 and the yoke unit 380, the frame 410 is not disposed, and thus due to the attractive force between the magnets 441 and 451 and the yoke unit 380 The lens holder 420 may be inclined.

However, in the present invention, the third ball member 900 is disposed between the carrier 310 and the lens holder 420 to prevent the lens holder 420 from tilting.

Since the third ball member 900 directly supports the lens holder 420 between the carrier 310 and the lens holder 420, the third ball member 900 has a first axis (X-axis) of the lens holder 420 ) And the movement in the direction of the second axis (Y axis) can be guided.

In this way, the frame 410 is not disposed in an area where an attractive force acts between the magnets 441 and 451 and the yoke unit 380, but the third ball member 900 is in an area where the frame 410 is not disposed. By arranging the lens holder 420 to be supported by the third ball member 900, while having a shake correction function, the size of the lens driving device 500 and the camera module 1000 (in the direction of the optical axis (Z axis)) Height) can be reduced.

Since the biased pressing force is applied to the lens holder 420, the magnitude of the pressing force applied to the second ball member 800 and the third ball member 900 supporting the lens holder 420 is also different from each other.

For example, since the pressing force applied to the lens holder 420 is greatest in the area where the magnets 441 and 451 and the yoke portion 380 face each other, the magnitude of the pressing force applied to the third ball member 900 is It is larger than the magnitude of the pressing force applied to the second ball member 800.

In addition, the magnitude of the pressing force applied to the third ball member 900 is greater than the magnitude of the pressing force applied to the first ball member 700.

As described above, the cross-sectional shape of the guide groove farthest from the third guide grooves 910 and 920 accommodating the third ball member 900 to which the greatest pressing force is applied and the third guide grooves 910 and 920 The cross-sectional shapes of the guide grooves arranged relatively close together are different from each other.

Meanwhile, as the sizes of the lens driving apparatus 500 and the camera module 1000 according to the present invention are reduced, a part of the lens barrel 200 may maintain a state protruding to the outside of the case 110 (see FIG. 1 ). ).

For example, even when the lens barrel 200 is located at the lowest point in the optical axis (Z axis) direction, a part of the lens barrel 200 may protrude outside the case 110.

Through the above embodiments, the lens driving apparatus 500 and the camera module 1000 including the same according to the exemplary embodiment of the present invention may have a shake correction function while miniaturizing the size.

In the above, the configuration and features of the present invention have been described based on the embodiments according to the present invention, but the present invention is not limited thereto, and it is understood that various changes or modifications can be made within the spirit and scope of the present invention. It will be apparent to those skilled in the art, and therefore, such changes or modifications are found to belong to the appended claims.

110: case 120: housing
130: substrate 200: lens barrel
210: stopper 300: focus adjustment unit
310: carrier 400: shake correction unit
410: frame 420: lens holder
500: lens drive device 600: image sensor unit
700: first ball member 800: second ball member
900: third ball member 1000: camera module

Claims (14)

housing;
A carrier accommodated in the housing and movable in the optical axis direction;
A frame and a lens holder accommodated in the carrier and movable together with the carrier in the optical axis direction;
A lens barrel mounted on the lens holder;
A first shake correction driver including a first magnet disposed on the lens holder and a first coil facing the first magnet;
A second shake correction driver including a second magnet disposed on the lens holder and a second coil facing the second magnet;
A focus adjustment driver including a third magnet disposed on the carrier and a third coil facing the third magnet;
A yoke portion facing the first magnet and the second magnet in the optical axis direction and disposed on the carrier;
A first ball member disposed between the carrier and the frame and movable in a first axis direction perpendicular to the optical axis direction; And
A second ball member disposed between the frame and the lens holder and movable along a second axis direction perpendicular to the first axis direction; and
The frame is disposed between the carrier and the lens holder,
The carrier and the lens holder have a camera module having surfaces that directly face each other.
The method of claim 1,
The frame has an opening in a portion corresponding to an area in which the carrier and the lens holder directly face each other in the optical axis direction.
The method of claim 1,
The frame is a camera module having a flat shape of a'a' shape.
The method of claim 1,
The camera module further comprises a first position sensor facing the first magnet in the first shake correction driver.
The method of claim 1,
The camera module further comprises a second position sensor facing the second magnet and the second shake correction driver.
The method of claim 1,
The camera module further comprises a third position sensor facing the third magnet in the focus adjustment driver.
The method of claim 1,
A first guide groove is provided on a surface of the carrier and the frame facing each other in the optical axis direction,
A camera module having a second guide groove on a surface of the frame and the lens holder facing each other in the optical axis direction.
The method of claim 7,
The first guide groove includes a plurality of guide grooves, some of the guide grooves have a cross-sectional shape of a'∪' shape, and the remaining guide grooves have a cross-sectional shape of a'∨' shape. .
The method of claim 8,
When viewed in the direction of the optical axis, the guide groove having a cross-sectional shape of the'∪' shape is disposed farthest from the area where the carrier and the lens holder directly face each other among the plurality of guide grooves of the first guide groove. Camera module.
The method of claim 7,
The second guide groove includes a plurality of guide grooves, some of the guide grooves have a cross-sectional shape of a'∪' shape, and the remaining guide grooves have a cross-sectional shape of a'∨' shape. .
The method of claim 10,
When viewed from the direction of the optical axis, the guide groove having a cross-sectional shape of the'∪' shape is disposed farthest from the area where the carrier and the lens holder directly face each other among the plurality of guide grooves of the second guide groove. Camera module.
The method of claim 1,
A camera module to which a stopper covering at least a portion of an upper surface of the lens holder is coupled to the carrier.
The method of claim 1,
The camera module includes a first yoke portion facing the first magnet in the optical axis direction, and a second yoke portion facing the second magnet in the optical axis direction.
The method of claim 1,
The frame and the lens holder are movable together in the first axis direction,
The lens holder is a camera module capable of moving relative to the frame in the second axis direction.

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