阅读说明：本技术 透镜移动单元、透镜驱动装置、摄像头模块和智能电话 (Lens moving unit, lens driving device, camera module, and smart phone ) 是由 朴相沃 孙秉旭 李圣民 李准泽 于 2015-02-25 设计创作，主要内容包括：根据实施例的透镜驱动装置包括：可移动单元,上面安装有至少一个透镜；第一线圈和驱动磁体,彼此相对且相互作用使得可移动单元在透镜的光轴方向上移动；感测可移动单元在光轴方向上的位置的位置传感器或包含位置传感器的驱动器；以及极性磁化磁体,被布置为面对位置传感器或驱动器,其中极性磁化磁体包括：第一侧表面,面对位置传感器并且具有第一极性；以及第二侧表面,面对位置传感器,被布置为在与光轴方向平行的方向上与第一侧表面间隔开或者被布置为紧靠第一侧表面,并且具有与第一侧表面的第一极性相反的第二极性,并且第一侧表面在光轴方向上的长度可以等于或大于第二侧表面在光轴方向上的长度。(The lens driving device according to the embodiment includes: a movable unit on which at least one lens is mounted; a first coil and a driving magnet facing each other and interacting with each other to move the movable unit in an optical axis direction of the lens; a position sensor or a driver including a position sensor that senses a position of the movable unit in the optical axis direction; and a polar magnetized magnet arranged to face the position sensor or the driver, wherein the polar magnetized magnet includes: a first side surface facing the position sensor and having a first polarity; and a second side surface facing the position sensor, arranged to be spaced apart from or arranged to abut against the first side surface in a direction parallel to the optical axis direction, and having a second polarity opposite to the first polarity of the first side surface, and a length of the first side surface in the optical axis direction may be equal to or greater than a length of the second side surface in the optical axis direction.)

1. A lens moving unit, the lens moving unit comprising:

a cover member including an upper surface and a plurality of sidewalls extending from the upper surface;

a housing member provided on the cover member, the housing member including: a housing base, and first, second, third, and fourth posts extending from respective corners of the housing base;

A bobbin provided on the housing member and configured to move in an optical axis direction;

A pair of driving magnets provided on the cover member;

A coil unit disposed on the bobbin and facing the pair of driving magnets;

A sensing magnet disposed on the bobbin;

A position sensor configured to detect the sensing magnet; and is

Wherein the pair of driving magnets includes: a first magnet overlapping a first opening between the first and second posts of the housing member, and a second magnet overlapping a second opening between the third and fourth posts of the housing member,

Wherein no drive magnet overlaps a third opening between the first and fourth posts and a fourth opening between the second and third posts of the housing member, and

Wherein the sensing magnet overlaps the third opening of the housing member.

2. The lens moving unit according to claim 1, wherein the first magnet is fixed to a first side wall of the cover member corresponding to the first opening and the second magnet is fixed to a second side wall of the cover member corresponding to the second opening by an adhesive, respectively.

3. a lens driving device comprising:

A cover member including an upper plate and a side plate extending from the upper plate;

A spool disposed in the cover member;

A coil disposed on the bobbin;

A first magnet disposed between the coil and the side plate of the cover member;

An elastic member coupled to the bobbin;

A second magnet disposed on the bobbin;

A circuit board disposed on the side plate of the cover member; and

a sensor disposed on the circuit board and facing the second magnet,

Wherein the first magnet is fixed to the side plate of the cover member by an adhesive,

Wherein the elastic member includes two lower elastic members coupled with a lower portion of the bobbin and spaced apart from each other, and

Wherein each of the two lower elastic members is soldered to the circuit board.

4. the lens driving device according to claim 3, wherein the circuit board is provided inside the side plate of the cover member.

5. A lens driving device comprising:

A cover member including an upper plate and a side plate extending from the upper plate;

A spool disposed in the cover member;

A coil disposed on the bobbin;

A first magnet disposed between the coil and the side plate of the cover member;

An elastic member coupled to the bobbin;

A second magnet disposed on the bobbin;

A circuit board disposed on the side plate of the cover member; and

a sensor disposed on the circuit board and facing the second magnet,

Wherein the first magnet is provided on the side plate of the cover member,

Wherein the first magnet includes a plane facing the coil,

Wherein the elastic member includes two lower elastic members coupled with a lower portion of the bobbin and spaced apart from each other, and

Wherein each of the two lower elastic members is soldered to the circuit board.

6. A lens driving device comprising:

A cover member including a first side, a second side disposed opposite the first side, a third side between the first side and the second side, and a fourth side disposed opposite the third side;

A housing member provided in the cover member;

A bobbin provided in the housing member, wherein the bobbin includes a recess formed in an inward direction from an outer circumferential surface of the bobbin;

A coil disposed to surround an outer circumferential surface of the bobbin;

An elastic member coupled to the bobbin;

A first drive magnet disposed between the coil and the first side of the cover member and a second drive magnet disposed between the coil and the second side of the cover member;

A sensing magnet positioned toward the third side of the cover member;

A position sensor facing the magnet and configured to sense movement of the bobbin in a first direction along an optical axis of the lens or in a first direction parallel to the optical axis of the lens,

Wherein the third side of the cover member includes an opening at a position corresponding to the sensing magnet.

7. The lens driving device according to claim 6, wherein the sensing magnet overlaps with the fourth side face of the cover member in a direction perpendicular to the fourth side face of the cover member facing the bobbin.

8. A lens driving device comprising:

a cover member including a first side, a second side disposed opposite the first side, a third side between the first side and the second side, and a fourth side disposed opposite the third side;

a housing member provided in the cover member;

A bobbin provided in the housing member, wherein the bobbin includes a first recess and a second recess formed in an inward direction from an outer circumferential surface of the bobbin;

A coil disposed to surround an outer circumferential surface of the bobbin;

An elastic member coupled to the bobbin;

A first drive magnet disposed between the coil and the first side of the cover member and a second drive magnet disposed between the coil and the second side of the cover member;

A weight balancing member provided in the first and second recesses of the bobbin, wherein the weight balancing member includes at least one magnet placed to face the third side of the cover member;

A position sensor facing the at least one magnet, the position sensor configured to detect movement of the bobbin in a first direction along or parallel to an optical axis of the lens,

Wherein the first and second recesses are symmetrical with respect to a center of the bobbin.

9. a lens driving device comprising:

A cover member including an upper plate and a side plate extending from the upper plate;

A spool disposed in the cover member;

A coil disposed on the bobbin;

A driving magnet facing the coil and disposed between the coil and the side plate of the cover member;

A sensing magnet disposed on the bobbin;

A circuit board disposed between the bobbin and the side plate of the cover member; and

A sensing component disposed on the circuit board,

Wherein the sensing magnet comprises a first surface facing the sensing component,

Wherein the sensing component includes a second surface facing the first surface of the sensing magnet, and

wherein a center of the second surface of the sensing part is disposed at a position higher than a position of a center of the first surface of the sensing magnet.

10. The lens driving device according to claim 9, wherein the first surface of the sensing magnet comprises: an upper region having a first polarity, and a lower region having a second polarity different from the first polarity and disposed below the upper region, and

Wherein a length of the upper region in an optical axis direction is larger than a length of the lower region in the optical axis direction.

11. The lens driving device according to claim 10, wherein the sensing member overlaps the upper region in a direction perpendicular to the optical axis direction, and

Wherein the sensing member does not overlap with the lower region in the direction perpendicular to the optical axis direction.

12. The lens driving device according to claim 9, wherein the bobbin comprises: a receiving recess formed on a side surface of the bobbin,

wherein the sensing magnet is disposed on the accommodation recess of the bobbin, and

Wherein the sensing magnet is disposed between the bobbin and the coil in a direction perpendicular to an optical axis direction.

13. The lens driving device according to claim 9, comprising a housing member provided in the cover member, and

Wherein the drive magnet is disposed on the housing member.

14. The lens driving device according to claim 13, comprising:

A base disposed below the bobbin and coupled with the side plate of the cover member;

An upper elastic member coupled with the bobbin and the housing; and

a lower elastic member disposed below the upper elastic member and coupled with the bobbin and the base.

15. The lens driving device according to claim 9, wherein the driving magnet is directly fixed to the side plate of the cover member.

16. The lens driving device according to claim 9, wherein the side plate of the cover member includes: a first side plate and a second side plate opposed to each other, and a third side plate and a fourth side plate disposed between the first side plate and the second side plate and opposed to each other,

Wherein the driving magnet includes: a first magnet provided on the first side plate of the cover member, and a second magnet provided on the second side plate of the cover member, and

Wherein no drive magnets are provided on the third and fourth side plates of the cover member.

17. The lens driving device according to claim 16, wherein at least a part of the circuit board is provided on an inner surface of the third side plate of the cover member.

18. The lens driving device according to claim 9, wherein the circuit board includes a plurality of terminals provided on a lower end of the circuit board.

19. The lens driving device according to claim 9, wherein the sensing magnet comprises a bipolar magnetized magnet.

20. The lens driving device according to claim 10, wherein the first polarity is an S-pole and the second polarity is an N-pole.

21. the lens driving device according to claim 9, wherein the sensing member includes a hall sensor.

22. a camera module, comprising:

a printed circuit board, i.e., PCB;

An image sensor disposed on the printed circuit board;

The lens driving device of claim 9, which is disposed on the printed circuit board; and

A lens coupled with the bobbin of the lens driving device.

23. A smartphone comprising the camera module of claim 22.

24. A lens driving device comprising:

A cover member including an upper plate and a side plate extending from the upper plate;

a spool disposed in the cover member;

A coil disposed on the bobbin;

A driving magnet facing the coil and disposed between the coil and the side plate of the cover member;

A sensing magnet disposed on the bobbin;

A circuit board disposed between the bobbin and the side plate of the cover member; and

A sensing component disposed on the circuit board,

wherein the sensing magnet comprises a first surface facing the sensing component,

Wherein the sensing component comprises a second surface facing the first surface of the sensing magnet,

wherein the first surface of the sensing magnet comprises: an upper region having a first polarity, and a lower region having a second polarity different from the first polarity and disposed below the upper region, and

Wherein a length of the upper region in an optical axis direction is larger than a length of the lower region in the optical axis direction.

25. the lens driving device according to claim 24, wherein the sensing member overlaps the upper region in a direction perpendicular to the optical axis direction, and

Wherein the sensing member does not overlap with the lower region in the direction perpendicular to the optical axis direction.

26. The lens driving device according to claim 24, wherein a center of the sensing member is provided at a position higher than a position of a center of the sensing magnet.

27. A lens driving device comprising:

A cover member including an upper plate and a side plate extending from the upper plate;

A spool disposed in the cover member;

A coil disposed on the bobbin;

A driving magnet facing the coil and disposed between the coil and the side plate of the cover member;

A sensing magnet disposed on the bobbin;

A circuit board disposed between the bobbin and the side plate of the cover member; and

a sensing part disposed on the circuit board and facing the sensing magnet,

Wherein the sensing part is disposed at a position closer to an upper surface of the sensing magnet than to a lower surface of the sensing magnet.

28. The lens driving device according to claim 27, wherein a center of the sensing part is provided at a position higher than a position of a center of the sensing magnet.

Technical Field

background

Recently, products such as mobile phones, smart phones, tablet computers, notebook computers, etc. having built-in micro digital cameras in IT field have been actively developed. A camera module including a digital camera is required to have various functions such as auto-focusing, reducing shutter shake, zooming function, etc., and its recent development trend is focused on increasing the number of pixels and miniaturization.

A conventional camera module may include a lens driving apparatus capable of performing an auto-focusing function and a hand-shake compensation function. The lens driving apparatus may be constructed in various ways, in which a voice coil unit motor is generally used. The voice coil unit motor operates by an electromagnetic interaction between a magnet fixed to the housing and a coil unit wound on an outer circumferential surface of a bobbin coupled to the lens barrel, thereby performing an auto-focusing function. An actuator (activator) module having such a voice coil motor is configured to enable a vertically movable bobbin to reciprocate in a direction parallel to the optical axis direction while being elastically supported by a lower elastic member and an upper elastic member.

IT products having a conventional built-in micro digital camera include a lens driving apparatus for setting a focal length of a lens by adjusting a distance between an image sensor and the lens. However, the conventional micro digital camera has a problem in that it takes a considerably long autofocus time to perform the autofocus function. Therefore, many efforts are made to shorten the auto-focusing time, but the performance of the lens driving apparatus may be deteriorated due to unstable electromagnetic force and eccentricity of the lens barrel caused by the magnetic force.

A conventional camera module may include a hall sensor (not shown) and a sensing magnet (not shown) which are disposed to be opposite to each other in a direction perpendicular to an optical axis direction of the lens so as to detect a focal position of the lens. In this case, the hall sensor senses the magnetic field of the sensing magnet and outputs a voltage corresponding thereto. The position of the lens in the optical axis direction can be detected by using the voltage output from the hall sensor, but the hall sensor cannot accurately sense the movement of the lens in the optical axis direction, and therefore, there is a limit to the ability to detect the position of the lens.

disclosure of Invention

Technical problem

Drawings

Fig. 1 shows a schematic perspective view of a camera module according to a first embodiment.

Fig. 2 shows an exploded perspective view of the camera module shown in fig. 1.

Fig. 3 shows a perspective view of the spool shown in fig. 2.

Fig. 4 shows a front view of the camera module shown in fig. 1.

Fig. 5 shows a plan view of the camera module taken along line I-I' in fig. 4.

Fig. 6 shows a front view of the lens driving apparatus after removing the circuit board from the camera module shown in fig. 1.

Fig. 7 shows a schematic perspective view of a lens driving device according to a second embodiment.

Fig. 8 shows a schematic exploded perspective view of an embodiment of the lens driving device according to fig. 7.

fig. 9 shows a schematic perspective view of the embodiment of the lens driving apparatus according to fig. 7 with the cover shell (cover can) removed.

Fig. 10 is a schematic plan perspective view of a housing member according to another embodiment.

FIG. 11 is a schematic bottom perspective view of a housing member according to another embodiment.

Fig. 12 shows a schematic exploded perspective view of a drive magnet, a housing member, a first circuit board, and a displacement sensing portion according to another embodiment.

FIG. 13 illustrates a plan perspective view of an upper resilient member according to one embodiment.

FIG. 14 illustrates a plan perspective view of a lower resilient member according to one embodiment.

Fig. 15 shows a plan perspective view of a spool according to another embodiment.

fig. 16 shows a bottom perspective view of a spool according to another embodiment.

Fig. 17 shows an exploded perspective view of a bobbin, a first coil, a displacement sensing portion, and a sensing magnet according to another embodiment.

Fig. 18 shows a schematic bottom perspective view of a bobbin, a first coil, first and second drive magnets, a displacement sensing portion, and a sensing magnet according to another embodiment.

Fig. 19 is a schematic perspective view of a lens driving device according to a third embodiment.

fig. 20 is a schematic exploded perspective view of the lens driving device shown in fig. 19.

Fig. 21 is a schematic perspective view of the lens driving device in fig. 19 with a cover member removed.

Fig. 22 is a schematic plan view of fig. 21.

Fig. 23 is a schematic perspective view of a drive magnet, a housing member, and a displacement sensing portion according to yet another embodiment.

Fig. 24 is a schematic perspective view of the drive magnet, the housing member, and the first circuit board when viewed from a different angle from fig. 23.

Fig. 25 is a schematic bottom perspective view of a drive magnet, a housing member, and a first circuit board according to yet another embodiment.

Fig. 26 is a schematic exploded perspective view of a driving magnet, a housing member, a first circuit board, and a displacement sensing part according to yet another embodiment.

fig. 27 is a schematic plan view of an upper elastic member according to another embodiment.

fig. 28 is a schematic plan view of a lower elastic member according to another embodiment.

fig. 29 is a schematic perspective view of a spool according to yet another embodiment.

fig. 30 is a schematic bottom perspective view of a bobbin and a sensing magnet according to yet another embodiment.

Fig. 31 is a schematic exploded perspective view of a bobbin, a first coil, and a sensing magnet according to yet another embodiment.

fig. 32 is a partially enlarged perspective view of a state in which the bobbin and the sensing magnet are coupled according to the embodiment.

Fig. 33 is a partial enlarged bottom view of a state in which a bobbin and a sensing magnet are coupled according to an embodiment.

fig. 34 is a partially enlarged perspective view for explaining a housing recess of the bobbin according to the embodiment.

Fig. 35 is a schematic longitudinal cross-sectional view of a bobbin, a first coil, and a sensing magnet according to yet another embodiment.

Fig. 36 shows a schematic cross-sectional view of a lens driving device according to embodiment 4-1.

Fig. 37a and 37b show cross-sectional views of the embodiment of the bipolar magnetized magnet shown in fig. 36, respectively.

Fig. 38 is a graph for explaining the operation of the lens driving device shown in fig. 36.

Fig. 39 shows a state in which the lens driving device shown in fig. 36 moves in the optical axis direction.

Fig. 40 is a graph showing the displacement of the movable unit according to the current supplied to the first coil in the lens driving device according to the fourth embodiment.

Fig. 41 shows a sectional view of the lens driving device according to the 4 th to 2 nd embodiment.

Fig. 42 shows a cross-sectional view of the lens driving device according to the 4 th to 3 rd embodiments.

Fig. 43a and 43b show cross-sectional views of the embodiment of the bipolar magnetized magnet shown in fig. 42, respectively.

Fig. 44 shows a sectional view of the lens driving device according to the 4 th to 4 th embodiments.

fig. 45 shows a cross-sectional view of the lens driving device according to the 4 th to 5 th embodiments.

Fig. 46 shows a cross-sectional view of the lens driving device according to the 4 th to 6 th embodiments.

Fig. 47 is a graph showing the displacement of the movable unit according to the current supplied to the first coil in the lens driving device shown in fig. 45 and 46.

Fig. 48 is a graph showing the magnetic field intensity sensed by the position sensor, which varies depending on the moving distance of the movable unit in the optical axis direction, in the respective arrangement relationship between the position sensor and the bipolar magnetized magnet.

Fig. 49a and 49b are graphs showing displacement according to the magnetic field strength sensed by the position sensor.

fig. 50 is a graph for explaining a change in magnetic field intensity according to a moving distance of a movable unit in a lens driving device according to a comparative example.

Fig. 51 is a graph illustrating a change in a magnetic field sensed by a position sensor according to a motion of a movable unit in a lens driving apparatus according to an embodiment.

Embodiments relate to a lens driving apparatus and a camera module including the same.