Anti-shake device for a lens module

• US 20120182436A1
• Filed: 05/09/2011
• Published: 07/19/2012
• Est. Priority Date: 01/14/2011
• Status: Active Grant

• Current Assignee: Tdk Taiwan Corp. (TDK Corporation)
• Original Assignee: Tdk Taiwan Corp. (TDK Corporation)
• Inventors: Hu, Chao Chang, Chen, Shu Shan
• Granted Patent: US 8,928,766 B2
• Time in Patent Office: Days
• US Class Current: 348/208.99
• CPC Class Codes: G03B 2205/0061 using piezoelectric actuators
• CPC Class Codes: G03B 5/00 Adjustment of optical system relative to image or object surface other than for focusing
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position

Abstract

An anti-shake device furnished between a lens module and an image sensor. An optical path is defined along the lens module and image sensor. The anti-shake device comprises a base plate, at least one piezoelectric member and a circuit member. The base plate is located in the optical path and has a surface facing the lens module, wherein a first axial direction and a second axial direction are defined on the surface. The piezoelectric member is located on the base plate and contacts with the lens module. The circuit member located on the base plate comprises a control module for controlling the piezoelectric member to drive the lens module moving alone the first and second axial directions in order to adjust the deviation caused by shaking.

Claims

1. An anti-shake device for a lens module, located between a lens module and an image sensor, an optical path being defined between the lens module and the image sensor, the anti-shake device comprising:

a base plate, having a surface perpendicular to the optical path, a first axial direction and a second axial direction being defined on the surface;

at least a piezoelectric member, located on the base plate at a position close to a bottom surface of the lens module, the piezoelectric member able to move the lens module if the piezoelectric member is actuated by a voltage; and

a circuit member, located on the base plate, electrically connected with said at least a piezoelectric member, further comprising a control module for providing the voltage to the piezoelectric member.

2. The anti-shake device for a lens module according to claim 1, wherein said at least a piezoelectric member includes two piezoelectric motors positioned perpendicularly on said base plate to be in charge of deviation compensations upon said lens module with respect to said base plate along said first axial direction and said second axial direction, respectively.

3. The anti-shake device for a lens module according to claim 1, further comprising a position-detecting module located on said base plate for detecting a position deviation of said lens module from said optical path, said control module on said base plate able to actuate said piezoelectric member to move said lens module so as to compensate the position deviation.

4. The anti-shake device for a lens module according to claim 1, further including a plurality of elastic elements located between said lens module and said base plate for maintaining substantial spacing between said lens module and said base plate, wherein, said elastic elements are fixed to side-surfaces of the base plate respectively.

5. The anti-shake device for a lens module according to claim 4, wherein each said elastic element is fixed to a respective corner of said base plate and extended along a direction parallel to said optical path.

6. The anti-shake device for a lens module according to claim 2, further including a friction plate mounted to said bottom surface of said lens module, the friction plate being elastically depressed upon each top of said at least a piezoelectric member so as to increase friction between said lens module and said at least a piezoelectric member.

7. The anti-shake device for a lens module according to claim 6, further including two balance supports mounted at positions on the base plate to correspond to the positions of the piezoelectric motors in such a manner that, not only the lens module can pose a substantial parallel relation to the base plate, but also the friction between the balance supports and the friction plate can be reduced.

8. The anti-shake device for a lens module according to claim 7, wherein said balance support is a roller ball

9. The anti-shake device for a lens module according to claim 1, wherein said lens module is selected from the group of a zoom lens module and a focusing lens module;

wherein said image sensor is selected from the group of a CCD module and a CMOS module; and

wherein said circuit member is selected from the group of a circuitry printed on said base plate, a circuitry buried inside said base plate, and a flexible circuit board on said base plate.

10. The anti-shake device for a lens module according to claim 4, wherein said elastic element is selected from the group of a bent-blade spring and a coil spring.

11. The anti-shake device for a lens module according to claim 4, wherein each said elastic element is a spring element that provides a preset tension to pull said lens module downward to said base plate and acts as an electric-conductive path between said lens module and said circuit member for transmitting a control signal or a power signal between said lens module and said circuit member.

12. An anti-shake device for a lens module, located between a lens module and an image sensor, an optical path being defined between the lens module and the image sensor, the anti-shake device comprising:

a base plate, having a surface perpendicular to the optical path, a first axial direction and a second axial direction being defined on the surface;

two piezoelectric members, located on the base plate at a position close to a bottom surface of the lens module, these two piezoelectric members being positioned perpendicularly and able, after being applied by a voltage, to move the lens module along the first axial direction and the second axial direction;

at least a position-detecting module, located on the base plate for detecting a position deviation of the lens module from the optical path; and

a circuit member, located on the base plate, electrically connected with the piezoelectric members and said at least a position-detecting module, further comprising a control module for providing the voltage to the piezoelectric member;

wherein, according to the position deviation detected by said at least a position-detecting module, the control module provides the voltage to the piezoelectric members so as to actuate the piezoelectric members to move, along the first axial direction and the second axial direction, the lens module with respect to the base plate for compensating the position deviation.

13. The anti-shake device for a lens module according to claim 12, further including a friction plate and a plurality of elastic elements, the friction plate being located to said bottom surface of said lens module and depressed upon said two piezoelectric members, the plurality of elastic elements being located between said lens module and said base plate for elastically mounting said lens module above said base plate.

14. The anti-shake device for a lens module according to claim 13, wherein said elastic element is selected from the group of a bent-blade spring and a coil spring, and wherein said elastic element provides a preset tension to pull said lens module downward to said base plate and acts as an electric-conductive path between said lens module and said circuit member for transmitting a control signal or a power signal between said lens module and said circuit member.

15. The anti-shake device for a lens module according to claim 13, wherein said elastic elements are fixed to side-surfaces of the base plate respectively.

16. The anti-shake device for a lens module according to claim 15, wherein each said elastic element is fixed to a respective corner of said base plate and extended along a direction parallel to said optical path.

17. The anti-shake device for a lens module according to claim 13, further including two balance supports mounted at positions on the base plate to correspond to the positions of the piezoelectric members in such a manner that, not only the lens module can pose a substantial parallel relation to the base plate, but also the friction between the balance supports and the friction plate can be reduced.

18. The anti-shake device for a lens module according to claim 17, wherein said balance support is a roller ball

19. The anti-shake device for a lens module according to claim 12, wherein said circuit member is selected from the group of a circuitry printed on said base plate, a circuitry buried inside said base plate, and a flexible circuit board on said base plate.

20. The anti-shake device for a lens module according to claim 12, further including a housing having an opening corresponding to said lens module, said lens module further including a cover plate having a central penetration hole corresponding to the opening of the housing for allowing said optical path to pass therethrough, the cover plate further having a plurality of locating protrusions located to a rim thereof for matching in space with corresponding locating holes at said base plate, each of said elastic elements being mounted, at both end thereof, between the respective locating protrusion and the corresponding locating hole, said circuit member further including a plurality of leads extending out to a rim of said base plate for transmitting power and control signals to said lens module and said piezoelectric members.