Optical image stabilization using tangentially actuated MEMS devices

• US 9,019,390 B2
• Filed: 09/28/2011
• Issued: 04/28/2015
• Est. Priority Date: 09/28/2011
• Status: Active Grant

• Current Assignee: DigitalOptics Corporation MEMS (Adeia Inc.)
• Original Assignee: DigitalOptics Corporation MEMS (Adeia Inc.)
• Inventors: Gutierrez, Roman C., Calvet, Robert J.
• Primary Examiner(s): DAGNEW, MEKONNEN D
• Application Number:
  US13/247,895
• Publication Number:
  US 20130076919A1
• Time in Patent Office: 1,308 Days
• Field of Search: 310/309, 428/50, 257/415, 257/417, 735/141.8, 735/143.2, 348/208.99, 348/208.2, 348/208.1, 348/345, 348/207.99
• US Class Current: 348/208.99
• CPC Class Codes: G02B 27/646 compensating for small deviations, e.g. due to vibration or shake movement of one or more optical elements for control of motion blur in cameras, projectors or printers G03B2205/0007; image stabilisation in cameras peculiar to the presence or use of an electronic image sensor H04N23/68
• CPC Class Codes: G03B 2205/0046 Movement of one or more optical elements for zooming for optical zoom lenses in general G02B7/10
• CPC Class Codes: G03B 2205/0053 Driving means for the movement of one or more optical element
• CPC Class Codes: G03B 3/10 Power-operated focusing
• CPC Class Codes: H04N 23/681 Motion detection
• CPC Class Codes: H04N 23/685 performed by mechanical compensation

Abstract

In one example, an actuator device useful in, e.g., a camera for, e.g., optical image stabilization (OIS), includes a stage resiliently supported for movement within a plane, three or more actuators, each coupled to an outer periphery of the stage and operable to apply a force acting in the plane and tangentially to the stage when actuated, and an outer frame surrounding and supporting the stage and the actuators.

Claims

1. An actuator device, comprising:

a stage resiliently supported for movement within a plane, wherein the stage comprises a planar mounting structure disposed in the plane that is adapted to support an optical element;

three or more actuators, each coupled to an outer periphery of the stage and operable to apply a linear force along a straight line acting in the plane and tangentially to the stage when actuated;

a flexure interposed between each actuator and the outer periphery of the stage;

wherein at least two of the flexures are coupled to a common location on the outer periphery;

wherein the linear forces, when applied to the flexures, are configured to cooperate to effect the movement of the stage in any translational and/or any rotational direction within the plane; and

an outer frame surrounding and supporting the stage and the actuators.

2. The actuator device of claim 1, wherein the stage, the actuators and the outer frame are disposed generally coplanar with each other.

3. The actuator device of claim 1, wherein at least one of the flexures is a recurvate flexure, and wherein each flexure is coupled to an extended portion of the stage that extends along a line passing between two of the actuators.

4. The actuator device of claim 1, wherein at least one of the actuators comprises:

a fixed frame,

a moving frame resiliently supported for reciprocating movement relative to the fixed frame, and

a plurality of straight interdigitated teeth alternately attached to the fixed and the moving frames and oriented for reciprocal movement toward and away from each other in a tangential direction relative to the stage.

5. The actuator device of claim 4, wherein the moving frame is supported for movement relative to the fixed frame by at least one flexure.

6. The actuator device of claim 1, wherein at least one of the actuators comprises an electrostatic actuator.

7. The actuator device of claim 1, wherein the actuators are arranged at equal angular intervals around the outer periphery of the stage.

8. The actuator device of claim 1, further comprising a limit stop disposed between at least one of the actuators and the stage for limiting relative movement between the at least one actuator and the stage during a shock event.

9. The actuator device of claim 1, further comprising at least one locking arm coupled to the stage and at least one associated locking feature coupled to the outer frame and operable to engage a complementary locking feature on the locking arm when the stage is rotationally disposed in a parked state.

10. The actuator device of claim 1, wherein the stage, the actuators and the outer frame are formed integrally with each other from a substrate using at least one of micromachining and/or photolithography techniques.

11. A method for operating the actuator device of claim 1, the method comprising selectably actuating each of the actuators such that the stage moves in the plane with at least one of pure translational and/or pure rotational movement.

12. The method of claim 11, further comprising selectably actuating each of the actuators such that the stage moves with purely rotational movement from a parked state to an operating state or from an operating state to a parked state.

13. A camera, comprising:

a sensor having an image sensing surface;

an actuator device, including;

a stage resiliently supported for movement within a plane, wherein the stage comprises a planar mounting structure disposed in the plane;

three or more actuators, each coupled to an outer periphery of the stage and operable to apply a linear force along a straight line acting in the plane and tangentially to the stage when actuated;

a flexure interposed between each actuator and the outer periphery of the stage;

wherein at least two of the flexures are coupled to a common location on the outer periphery;

wherein the linear forces, when applied, are configured to cooperate to effect the movement of the stage in any translational and/or any rotational direction within the plane; and

an outer frame surrounding and supporting the stage and the actuators; and

an optical element disposed on the stage of the actuator device to move conjointly therewith and operable to focus an image of a subject on the image sensing surface of the sensor.

14. The camera of claim 13, further comprising:

a sensing apparatus for sensing at least one of vertical and/or horizontal accelerations of the camera and for outputting signals respectively corresponding thereto; and

,

a controlling apparatus for selectably controlling the actuators of the actuator device using the signals output from the sensing apparatus such that the image of the subject formed by the optical element on the sensing surface of the sensor remains stable during the accelerations of the camera.

15. A cellular telephone, a personal digital assistant (PDA), a laptop computer or a surveillance system incorporating the camera of claim 14.

16. A camera, comprising:

an actuator device, including;

a stage resiliently supported for movement within a plane, wherein the stage comprises a planar mounting structure disposed in the plane;

three or more actuators, each coupled to an outer periphery of the stage and operable to apply a linear force along a straight line acting in the plane and tangentially to the stage when actuated;

a flexure interposed between each actuator and the outer periphery of the stage;

wherein at least two of the flexures are coupled to a common location on the outer periphery;

wherein the linear forces, when applied, are configured to cooperate to effect the movement of the stage in any translational and/or any rotational direction within the plane; and

,

an outer frame surrounding and supporting the stage and the actuators;

a sensor disposed on the stage of the actuator device to move conjointly therewith and operable to sense an image of a subject focused on an image sensing surface thereof; and

an optical element disposed in front of the stage of the actuator device and operable to focus an image of a subject on the image sensing surface of the sensor.

17. The camera of claim 16, further comprising:

a sensing apparatus for sensing at least one of vertical and/or horizontal accelerations of the camera and for outputting signals respectively corresponding thereto; and

,

a controlling apparatus for selectably controlling the actuators of the actuator device using the signals output from the sensing apparatus such that the image of the subject formed by the optical element on the sensing surface of the sensor remains stable during the accelerations of the camera.

18. A cellular telephone, a personal digital assistant (PDA), a laptop computer or a surveillance system incorporating the camera of claim 17.

19. A method, comprising:

providing a stage resiliently supported for movement within a plane, wherein the stage comprises a planar mounting structure disposed in the plane;

coupling three or more actuators to an outer periphery of the stage, each of the actuators being operable to apply a linear force along a straight line acting within the plane and tangentially to the stage when actuated;

wherein the coupling comprises coupling each actuator to the outer periphery of the stage using a flexure interposed between each actuator and the outer periphery of the stage;

wherein at least two of the flexures are coupled to a common location on the outer periphery;

wherein the linear forces, when applied, are configured to cooperate to effect the movement of the stage in any translational and/or any rotational direction within the plane; and

,

selectably actuating each of the actuators such that the stage moves in the plane with at least one of pure translational and/or pure rotational movement therein.

20. The method of claim 19, further comprising:

sensing accelerations acting on the stage and the actuators;

outputting signals respectively corresponding to the accelerations; and

,

selectably controlling the actuators using the signals to stabilize an image of a subject formed by an optical element on a sensing surface of a sensor during the accelerations.