Optical image stabilizer for camera lens assembly

• US 9,081,203 B2
• Filed: 10/27/2009
• Issued: 07/14/2015
• Est. Priority Date: 11/28/2008
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Shin, Doo-Sik
• Primary Examiner(s): NGUYEN, THONG Q
• Application Number:
  US12/606,767
• Publication Number:
  US 20100134887A1
• Time in Patent Office: 2,086 Days
• Field of Search: 348/208.99, 3482081-20816, 359554-557, 359813-814, 359823-824
• US Class Current: 1/1
• CPC Class Codes: G02B 27/64 Imaging systems using optical elements for stabilisation of the lateral and angular position of the image
• 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 2205/0023 by tilting or inclining one or more optical elements with respect to the optical axis
• 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 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils
• CPC Class Codes: H04N 23/6812 based on additional sensors, e.g. acceleration sensors
• CPC Class Codes: H04N 23/687 by shifting the lens or sensor position

Abstract

An optical image stabilizer for correcting an image blurred by shaking of a hand while an object is photographed using a mobile communication terminal is provided. The optical image stabilizer includes an image sensor. A lens assembly is mounted on an optical axis of the image sensor. A housing contains the lens assembly. A rotator provided between the housing and the lens assembly surrounding the lens assembly rotates the lens assembly around a first axis perpendicular to the optical axis and a second axis perpendicular to the first axis in engagement with the lens assembly. A driving member rotates the rotator around the first and second axes. The optical image stabilizer can be mounted in a miniaturized lightweight photographing device, so that a clear image can be captured even during vibration of a photographing device caused by hand-shaking.

Claims

1. An optical image stabilizer for a camera lens assembly, comprising:

an image sensor;

a lens assembly mounted on an optical axis of the image sensor;

a housing in which the lens assembly is disposed;

a first axis rotator surrounding and engaged with the lens assembly, wherein the first axis rotator is configured to rotate the lens assembly around a first axis that is perpendicular to the optical axis;

a second axis rotator disposed between the first axis rotator and the housing, wherein the second axis rotator is configured to rotate the lens assembly around a second axis that is perpendicular to a plane including the first axis;

a first driving portion extending from an outer surface of the second axis rotator, through the second axis rotator, to an outer surface of the first axis rotator, wherein the first driving portion is configured to rotate the first axis rotator around the first axis; and

a second driving portion extending from an outer surface of the housing, through the housing, to the outer surface of the second axis rotator, wherein the second driving portion is configured to rotate the second axis rotator around the second axis.

2. The optical image stabilizer of claim 1, further comprising:

a first rotating portion provided on the first axis rotator and the second axis rotator, for rotating the first axis rotator around the first axis in the second axis rotator; and

a second rotating portion provided on the second axis rotator and the housing, for rotating the second axis rotator around the second axis in the housing.

3. The optical image stabilizer of claim 2, wherein the first rotating portion comprises:

a pair of first rotating grooves facing each other in a direction of the first axis, and formed in an outer periphery of the first axis rotator;

a pair of first rotating holes facing each other in the second axis rotator and facing the first rotating grooves; and

a pair of first coupling members passing through the first rotating holes and mounted in the first rotating grooves,

wherein the first axis rotator is configured to rotate around the first axis in the second rotator.

4. The optical image stabilizer of claim 3, wherein the second rotating portion comprises:

a pair of second rotating grooves facing each other in a direction of the second axis, and formed in an outer periphery of the second axis rotator;

a pair of second rotating holes formed in the housing and facing the second rotating grooves; and

a pair of second coupling members passing through the second rotating holes and mounted in the second grooves,

wherein the second axis rotator is adapted to rotate around the second axis in the housing.

5. The optical image stabilizer of claim 4, further comprising:

a first position-sensing portion provided on the first axis rotator and the second axis rotator, for sensing and controlling rotation of the first axis rotator in the second axis rotator; and

a second position-sensing portion provided on the second axis rotator and the housing, for sensing and controlling rotation of the second axis rotator in the housing.

6. The optical image stabilizer of claim 5, wherein the first position-sensing portion comprises:

a first permanent magnet provided at a position intersecting the second axis in the outer periphery of the first axis rotator; and

a first position sensor provided in the second axis rotator, and facing the first permanent magnet.

7. The optical image stabilizer of claim 6, wherein the second position-sensing portion comprises:

a second permanent magnet provided at a position intersecting the first axis in the outer periphery of the second axis rotator; and

a second position sensor provided at a position, facing the second permanent magnet, in the housing.

8. The optical image stabilizer of claim 1, wherein the first driving portion comprises:

a first piezoelectric actuator provided on the second axis rotator and engaged with the first axis rotator;

at least one first cylindrical rotating tip provided between the first piezoelectric actuator and the first axis rotator; and

a first elastic member for pressing the first piezoelectric actuator to the first axis rotator.

9. The optical image stabilizer of claim 8, wherein at least two first cylindrical rotating tips are driven in different oval shapes on a face of the first piezoelectric actuator according to power supply to the first piezoelectric actuator.

10. The optical image stabilizer of claim 9, wherein the first elastic member comprises a plate spring.

11. The optical image stabilizer of claim 8, wherein the second driving portion comprises:

a second piezoelectric actuator provided on the housing and engaged with the second axis rotator;

at least one second cylindrical rotating tip provided between the second piezoelectric actuator and the second axis rotator; and

a second elastic member for pressing the second piezoelectric actuator to the second axis rotator.

12. The optical image stabilizer of claim 11, wherein at least two second cylindrical rotating tips are driven in different oval shapes on a face of the second piezoelectric actuator according to power supply to the first piezoelectric actuator.

13. The optical image stabilizer of claim 11, wherein the second elastic member comprises a plate spring.

14. The optical image stabilizer of claim 1, wherein the first driving portion and the second driving portion each include a piezoelectric actuator.

15. An optical image stabilizer for a camera lens assembly, comprising:

a lens assembly;

a first axis rotator surrounding and engaged with the lens assembly, wherein the first axis rotator is configured to rotate the lens assembly around a first axis that is perpendicular to the optical axis;

a second axis rotator disposed between the first axis rotator and a housing, wherein the second axis rotator is configured to rotate the lens assembly around a second axis that is perpendicular to a plane including the first axis;

a first driving portion extending from an outer surface of the second axis rotator, through the second axis rotator, to an outer surface of the first axis rotator, wherein the first driving portion is configured to rotate the first axis rotator around the first axis; and

a second driving portion extending from an outer surface of the housing, through the housing, to the outer surface of the second axis rotator, wherein the second driving portion is configured to rotate the second axis rotator around the second axis.

16. The optical image stabilizer of claim 15, wherein the first driving portion and the second driving portion each include a piezoelectric actuator.