SOLID STATE OPTICAL MOTION COMPENSATION

• US 20090027544A1
• Filed: 07/25/2007
• Published: 01/29/2009
• Est. Priority Date: 07/25/2007
• Status: Abandoned Application

• Current Assignee: Aptina Imaging Corporation (ON Semiconductor Corporation)
• Original Assignee: Micron Technology, Inc.
• Inventors: Grewal, Roopinder Singh
• Application Number:
  US11/782,779
• Publication Number:
  US 20090027544A1
• Time in Patent Office: Days
• US Class Current: 348/352
• CPC Class Codes: H04N 23/68 for stable pick-up of the scene, e.g. compensating for camera body vibrations

Abstract

Methods and systems for capturing an image. Light is received through an imaging lens that has an adjustable focal center. A motion vector representing motion of the imaging lens is estimated and a shift vector is estimated in response to the motion vector. The shift vector is converted into a voltage gradient and provided to the imaging lens. The voltage gradient shifts the focal center of the imaging lens to compensate for the motion of the imaging lens.

Claims

1. A method for capturing an image, the method comprising:

receiving light through an imaging lens having an adjustable focal center;

estimating a motion vector representing motion of the imaging lens;

estimating a shift vector in response to the motion vector;

converting the shift vector into a voltage gradient; and

providing the voltage gradient to the imaging lens,

wherein the focal center of the imaging lens is shifted based on the voltage gradient to compensate for the motion of the imaging lens.

2. The method according to claim 1, further comprising detecting the motion by a motion sensor,

wherein the detected motion by the motion sensor is used to estimate the motion vector.

3. The method according to claim 1, wherein the light is captured as the image, the method further comprising:

capturing multiple images in a sequence;

correlating the multiple images to detect the motion of the imaging lens,

wherein the detected motion from the correlated multiple images is used to estimate the motion vector.

4. The method according to claim 1, wherein the shift vector is estimated from a look-up table or from a predetermined relationship between the estimated motion vector and a predetermined motion compensation by the imaging lens.

5. The method according to claim 1, wherein the shift vector is estimated by predicting further motion of the imaging lens based on the estimated motion vector and at least one previously estimated motion vector, the focal center shifted to compensate for the predicted further motion.

6. The method according to claim 1, wherein the shift vector is converted into the voltage gradient using a look-up table or a predetermined relationship between the estimated shift vector and focusing parameters of the imaging lens.

7. The method according to claim 1, wherein the motion changes over time and the steps of estimating the motion vector, estimating the shift vector, converting the shift vector and providing the voltage gradient to the imaging lens are repeated over time to compensate for the change in the motion.

8. The method according to claim 1, the step of estimating the shift vector including:

determining whether a change in the estimated motion vector from a previously estimated motion vector is greater than a threshold;

maintaining a previously determined voltage gradient to the imaging lens when the change in the estimated motion vector is less than or equal to the threshold; and

estimating the shift vector in response to the estimated motion vector when the change in the estimated motion vector is greater than the threshold.

9. The method according to claim 1, further comprising, prior to transmitting the light through the imaging lens:

generating an initial voltage gradient based on focusing parameters of the imaging lens;

providing the initial voltage gradient to the imaging lens,

wherein the imaging lens is formed according to the focusing parameters and the light is transmitted through the imaging lens according to the focusing parameters.

10. The method according to claim 9, wherein the imaging lens is formed into a positive lens or a negative lens according to the focusing parameters.

11. The method according to claim 1, wherein the voltage gradient generates a directional electric field across the imaging lens and the imaging lens includes particles capable of being reoriented relative to the directional electric field, the voltage gradient provided to the imaging lens reorienting the particles relative to the directional electric field.

12. The method according to claim 11, wherein the directional electric field includes multiple directional electric fields, the particles being reoriented within corresponding regions of the imaging lens according to the multiple directional electric fields.

13. Apparatus for capturing an image, the apparatus comprising:

an imaging lens having an adjustable focal center;

a motion vector estimator for estimating a motion vector representing motion of the imaging lens;

a lens shift estimator for estimating a shift vector in response to the motion vector; and

a converter for converting the shift vector into a voltage gradient,

wherein the voltage gradient is provided to the imaging lens and adjusts the focal center of the imaging lens to compensate for the motion of the imaging lens.

14. The motion compensator according to claim 13, further comprising a plurality of contacts providing on opposing sides of the imaging lens in a regularly spaced or irregularly spaced arrangement, the plurality of contacts configured to apply the voltage gradient to the imaging lens.

15. The motion compensator according to claim 13, wherein the motion vector estimator includes a motion sensor to detect the motion of the imaging lens, the motion vector estimator using the detected motion used to estimate the motion vector.

16. The motion compensator according to claim 13, wherein the motion vector estimator receives multiple images in a sequence, the motion vector estimator configured to correlate the multiple images to detect the motion of the imaging lens and use the detected motion to estimate the motion vector.

17. The motion compensator according to claim 13, further comprising storage for storing at least one of the estimated motion vector, the estimated shift vector, a first look-up table for estimating the shift vector by the lens shift estimator, a second look-up table for converting the shift vector into the voltage gradient by the converter, a first predetermined relationship between the estimated motion vector and a predetermined motion compensation for estimating the shift vector by the lens shift estimator, a second predetermined relationship between the estimated shift vector and focusing parameters of the imaging lens for converting the shift vector by the converter or the voltage gradient received fro the converter.

18. The motion compensator according to claim 13, wherein the lens shift estimator predicts a further motion of the imaging lens based on the estimated motion vector and at least one previously estimated motion vector, the focal center being shifted to compensate for the predicted further motion.

19. The motion compensator according to claim 13, at least one of the lens shift estimator or the converter including a processor for estimating the shift vector or converting the shift vector into the voltage gradient, respectively.

20. The motion compensator according to claim 13, wherein the voltage gradient includes predetermined focusing parameters for the imaging lens, the imaging lens configurable as a negative lens or positive lens having the predetermined focusing parameters responsive to the voltage gradient.

21. The motion compensator according to claim 13, wherein the imaging lens includes particles in a polymer matrix that are responsive to the voltage gradient, the voltage gradient generating a directional electric field across the imaging lens, the directional electric field being reoriented relative to the directional electric field.

22. The motion compensator according to claim 21, wherein the directional electric field includes multiple directional electric fields, the particles being reoriented within corresponding sections of the imaging lens according to the multiple directional electric fields.

23. An imaging device comprising:

a pixel array,

an imaging lens for providing an image onto the pixel array,

the imaging lens including both a fixed real center and an adjustable virtual center,

a motion vector estimator for estimating a motion vector of either the imaging lens or the pixel array, and

a lens shift estimator for estimating a shift vector in response to the motion vector,

wherein the virtual center of the imaging lens is adjusted with respect to the real center based on the shift vector.

24. The imaging device of claim 23 wherein

the imaging lens is oriented in a first X, Y plane of an orthogonal X, Y, Z axes,

the pixel array is oriented in a second X, Y plane of the orthogonal X, Y, Z axes, and

the motion vector and the shift vector are both oriented in either the first or second X, Y plane.

25. The imaging device of claim 24 wherein

the real center is located on a first line oriented perpendicular to both the pixel array and the imaging lens, and

the virtual center is located on a second line oriented parallel to the first line.

26. The imaging device of claim 23 wherein

the real center is located on a first line oriented perpendicular to both the pixel array and the imaging lens, and

the lens shift estimator provides a voltage gradient across the imaging lens for shifting the virtual center with respect to the real center, the virtual center located on a second line oriented parallel to the first line.

27. The imaging device of claim 26 wherein

the imaging lens includes particles that are reoriented based on the voltage gradient provide across the imaging lens.

28. The imaging device of claim 23 wherein

the imaging lens and the pixel array are integrated in a single housing, and

at least one motion sensor is integrated into the housing for sensing motion of the housing and providing the sensed motion to the motion vector estimator.

29. The imaging device of claim 28 wherein

the lens shift estimator is configured to output the shift vector for adjusting the virtual center of the imaging lens only if the input sensed motion is greater than a predetermined threshold value.