Imaging device employing optical motion sensor as gyroscope

• US 7,656,428 B2
• Filed: 05/05/2005
• Issued: 02/02/2010
• Est. Priority Date: 05/05/2005
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Inventors: Trutna, William R. Jr.
• Primary Examiner(s): Tran; Nhan T
• Application Number:
  US11/122,964
• Publication Number:
  US 20060251410A1
• Time in Patent Office: 1,734 Days
• Field of Search: 348/208.1, 348/208.4, 348/208.7, 348/208.11, 348/240.3, 348/335, 348/294
• US Class Current: 348/208.1
• CPC Class Codes: G03B 17/02 Bodies
• CPC Class Codes: G03B 2205/0007 Movement of one or more optical elements for control of motion blur imaging systems in general using optical elements for stabilisation of the position of the image G02B27/64
• CPC Class Codes: G03B 2217/005 Blur detection
• CPC Class Codes: G03B 5/02 Lateral adjustment of lens
• CPC Class Codes: H04N 2101/00 Still video cameras
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations
• CPC Class Codes: H04N 23/6811 based on the image signal
• CPC Class Codes: H04N 23/6812 based on additional sensors, e.g. acceleration sensors

Abstract

A motion sensor configured to control compensation for movement of an imaging device receiving light representative of a selected scene on an image plane. The motion sensor includes and array of photoelements and a controller. The array of photoelements is configured to acquire successive images of features of an environment within a field of view of the motion sensor; including a first image of features and a second image of features acquired at a time interval after the first image, the first and second images including common features. The controller is configured to receive and correlate the first and second images to detect movement of the imaging device about a first and a second axis during the time interval by detecting differences in locations of the common features relative to the array of photoelements, and to provide first and second compensation signals based on the correlation to control opto-mechanical adjustments to counter detected movement of the imaging device about the first and second axes so as to maintain a substantially fixed relationship between the selected scene and the imaging plane.

Claims

1. A motion sensor configured to control compensation for movement of an imaging device receiving light representative of a selected scene on an image plane, the motion sensor comprising:

an array of photoelements configured to acquire successive images of features of an environment within a field of view of the motion sensor;

including a first image of features and a second image of features acquired at a time interval after the first image, the first and second images including common features,

a controller configured to receive and correlate the first and second images to detect movement of the imaging device about a first axis and a second axis during the time interval by detecting differences in locations of the common features relative to the array of photoelements, and to provide first and second compensation signals based on the correlation to control opto-mechanical adjustments to counter detected movement of the imaging device about the first axis and the second axis so as to maintain a substantially fixed relationship between the selected scene and the imaging plane; and

an objective lens to direct light to the array of photoelements;

wherein the array of photoelements and the objective lens of the motion sensor are configured to have an angular resolution that substantially matches the angular resolution of a camera image sensor and of a zoom lens of the imaging device when the zoom lens is in a telephoto position at which the zoom lens has its longest focal length.

2. The motion sensor of claim 1, wherein the first image comprises a reference image.

3. The motion sensor of claim 1, wherein a first image of the successive images of features of the environment comprises the reference image and each subsequently acquired image of the successive images is correlated to the reference image to detect movement of the imaging device.

4. The motion sensor of claim 1, wherein the motion sensor comprises an integrated circuit package including the array of photoelements and the controller.

5. The motion sensor of claim 1, wherein the array of photoelements comprises a complimentary metal oxide semiconductor image sensor.

6. An imaging device comprising:

a stage moveable along a first axis and a second axis;

an imaging plane positioned on the stage and configured to receive light representative of a selected scene; and

a motion sensor comprising;

an array of photoelements positioned on the stage and configured to acquire successive images of features of an environment within a field of view of the motion sensor;

including a first image of features and a second image of features acquired at a time interval after the first image, the first and second images including common features, and

a controller configured to receive and correlate the first and second images to detect movement of the imaging device about the first axis and the second axis during the time interval by detecting differences in locations of the common features relative to the array of photoelements, and to provide first and second compensation signals based on the correlation to control movement of the stage to counter detected movement of the imaging device about the first axis and the second axis so as to maintain a substantially fixed relationship between the selected scene and the imaging plane;

a camera objective zoom lens associated with the imaging plane and a motion sensor objective lens associated with the motion sensor;

wherein the motion sensor objective lens has a focal length such that an angular resolution of the array of photoelements of the motion sensor substantially matches an angular resolution of an image sensor of the imaging device when the camera objective zoom lens is in a telephoto position at which the camera objective zoom lens has its longest focal length.

7. The imaging device of claim 6, wherein movement of the stage to counter detected movement of the imaging device about the first axis and the second axis maintains a substantially fixed relationship between the environment within the field of view of the motion sensor and the array of photoelements.

8. The imaging device of claim 6, including a first voice coil motor configured to move the stage along the first axis in response to the first compensation signal and a second voice coil motor configured to move the stage along the second axis in response to the second compensation signal.

9. The imaging device of claim 6, a plurality of objective lenses associated with the array of photoelements of the motion sensor, each objective lens of the plurality having a corresponding field of view, with the field of views of each of the plurality of objective lenses combining to form an effective field of view for the array of photoelements.

10. The imaging device of claim 9, wherein each lens of the plurality of objective lenses projects an image of features within the corresponding field of view onto the array of photoelements, wherein each image of features is different from one another.

11. A method of compensating for movement of an imaging device receiving light representative of a selected scene on an image plane, the method comprising:

configuring an image sensor and an objective lens to have an angular resolution that substantially matches the angular resolution of a camera image sensor and zoom lens of the imaging device when the zoom lens has its longest focal length;

acquiring successive images of features of an environment with the image sensor, including a first image of features and a second image of features acquired after at a time interval after the first image, the first and second image including common features;

correlating the first and second images to detect movement of the imaging device about a first axis and a second axis by detecting differences in locations of the common features relative to the image sensor;

controlling opto-mechanical adjustments based on the correlation to counter detected movement of the imaging device so as to maintain a substantially fixed relationship between the selected scene and the imaging plane.

12. The method of claim 11, wherein the first image comprises a reference image and the correlating includes selecting an initial image of the successive images of features of the environment as the reference image.

13. The method of claim 11, comprising updating the reference image with a subsequent image of the successive images of features based on selected operating criteria.

14. The method of claim 13, wherein updating the selected operating criteria comprises movement of the imaging device resulting in no common features between the first and second images.

15. The method of claim 11, wherein controlling opto-mechanical adjustments comprises adjusting a position of the image plane along the first axis and the second axis.

16. The method of claim 15, wherein controlling opto-mechanical adjustments comprises adjusting the position of the image plane together with a position of the image sensor along the first axis and the second axis.