OPTICAL TRACKING DEVICE USING MICROMIRROR ARRAY LENSES

• US 20080273191A1
• Filed: 05/02/2007
• Published: 11/06/2008
• Est. Priority Date: 05/02/2007
• Status: Active Grant

• Current Assignee: Stereo D Inc., Stereo Display, Inc.
• Original Assignee: Angstrom, Inc., Stereo Display, Inc.
• Inventors: Seo, Cheong Soo, Cho, Gyoung Il, Kim, Hye Young, Sohn, Jin Young
• Granted Patent: US 7,463,342 B2
• Time in Patent Office: Days
• US Class Current: 356/4.01
• CPC Class Codes: G01C 3/08 Use of electric radiation detectors
• CPC Class Codes: G01S 11/12 using electromagnetic waves other than radio waves
• CPC Class Codes: G01S 3/7864 T.V. type tracking systems
• CPC Class Codes: H04N 23/55 Optical parts specially adapted for electronic image sensors; Mounting thereof
• CPC Class Codes: H04N 23/60 Control of cameras or camera modules

Abstract

The optical tracking device of this invention comprises a lens unit, a control circuitry communicatively coupled to the lens unit, and an imaging unit optically coupled to the lens unit. The lens unit comprises at least one Micromirror Array Lens, wherein the Micromirror Array Lens comprises a plurality of micromirrors and is configured to have a plurality of optical surface profiles by controlling rotations or translations of the micromirrors. The optical tracking device of the invention further comprises an image processing unit, communicatively coupled to the imaging unit, configured to process the image information from the imaging unit and generates a control signal for the control circuit to control the lens unit. The optical tracking device of the present invention provides capability of tracking a target moving in a high speed, providing three-dimensional image information of the object, and compensating the aberration of the optical tracking device.

Claims

1. An optical tracking device, comprising:

(a) a lens unit comprising at least one Micromirror Array Lens, wherein the Micromirror Array Lens comprises a plurality of micromirrors and is configured to have a plurality of optical surface profiles by controlling rotations or translations of the micromirrors, wherein the motions of micromirrors in the Micromirror Array Lens in controlled to correct aberration;

(b) a control circuitry, communicatively coupled to the lens unit, configured to control the motions of micromirrors in the Micromirror Array Lens to form optical surface profiles for changing a focusing property of the lens unit; and

(c) an imaging unit comprising at least one image sensor, optically coupled to the lens unit, configured to receive a scene image formed by the lens unit to generate image information of the scene image.

2. The optical tracking device of claim 1, further comprising an image processing unit, communicatively coupled to the imaging unit, configured to process the image information from the imaging unit, wherein the image processing unit extracts target movement information and generates a control signal for the control circuit to control the lens unit.

3. The optical tracking device of claim 1, wherein the focusing property of the lens unit is an effective focal length of the lens unit.

4. The optical tracking device of claim 1, wherein the focusing property of the lens unit is an optical axis of the lens unit.

5. The optical tracking device of claim 1, wherein the focusing property of the lens unit is a magnification of the lens unit.

6. The optical tracking device of claim 1, wherein the focusing property of the lens unit is a field of view of the lens unit.

7. The optical tracking device of claim 1, wherein the motions of micromirrors in the Micromirror Array Lens is controlled to correct aberration.

8. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a flat mirror.

9. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a parabolic concave mirror.

10. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a spherical concave mirror.

11. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a hyperbolic concave mirror.

12. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate an elliptic concave mirror.

13. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a parabolic convex mirror.

14. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a spherical convex mirror.

15. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate a hyperbolic convex mirror.

16. The optical tracking device of claim 1, wherein the optical surface profile of the Micromirror Array Lens satisfies a convergence condition and a phase matching condition to simulate an elliptic convex mirror.

17. The optical tracking device of claim 1, wherein the Micromirror Array Lens is a primary mirror in the telescope type configuration.

18. The optical tracking device of claim 17, wherein the Micromirror Array Lens has an opening, wherein light can pass through the Micromirror Array Lens.

19. The optical tracking device of claim 1, wherein the Micromirror Array Lens is a secondary mirror in the telescope type configuration.

20. The optical tracking device of claim 1, wherein the Micromirror Array Lens is a variator, wherein the variator is configured to change the focusing property of the lens unit.

21. The optical tracking device of claim 1, wherein the Micromirror Array Lens is a compensator, wherein the compensator is configured to maintain focus of the lens unit.

22. The optical tracking device of claim 1, wherein the lens unit comprises a first Micromirror Array Lens and a second Micromirror Array Lens.

23. The optical tracking device of claim 22, wherein the first Micromirror Array Lens is arranged to reflect light from the scene to the second Micromirror Array Lens and the second Micromirror Array Lens is arranged to reflect the light from the first Micromirror Array Lens to the imaging unit.

24. The optical tracking device of claim 22, wherein the first Micromirror Array Lens and the second Micromirror Array Lens are positioned so that the path of the light reflected by the first Micromirror Array Lens and the second Micromirror Array Lens is not blocked.

25. The optical tracking device of claim 22, further comprising a beam splitter positioned between the first Micromirror Array Lens and the second Micromirror Array Lens.

26. The optical tracking device of claim 22, wherein the first Micromirror Array Lens and the second Micromirror Array form a telescope type configuration.

27. The optical tracking device of claim 22, wherein the first Micromirror Array Lens and the second Micromirror Array form a Newtonian type telescope configuration.

28. The optical tracking device of claim 22, wherein the first Micromirror Array Lens and the second Micromirror Array form a Cassegrain type telescope configuration.

29. The optical tracking device of claim 22, wherein the first Micromirror Array Lens and the second Micromirror Array form a Gregorian type telescope configuration.

30. The optical tracking device of claim 1, wherein the lens unit further comprises a focus lens or lens group.

31. The optical tracking device of claim 1, wherein the lens unit further comprises a relay lens or lens group.

32. The optical tracking device of claim 1, wherein the lens unit further comprises an erect lens or lens group.

33. The optical tracking device of claim 1, wherein the lens unit further comprises a find-focus lens or lens group having macroscopic mechanical lens movements, optically coupled to the Micromirror Array Lens.

34. The optical tracking device of claim 33, wherein the fixed-focus lens or lens group having macroscopic mechanical lens movements is a compensator, wherein the compensator is configured to maintain focus of the lens unit.

35. The optical tracking device of claim 33, wherein the fixed-focus lens or lens group having macroscopic mechanical lens movements is a variator, wherein the variator is configured to change the focusing property of the lens unit.

36. The optical tracking device of claim 1, wherein the lens unit further comprises a non-MMAL (Micromirror Array Lens) variable focus lens, wherein a focal length of the non-MMAL variable focus lens is changed.

37. The optical tracking device of claim 36, wherein the non-MMAL variable focus lens is a compensator, wherein the compensator is configured to maintain focus of the lens unit.

38. The optical tracking device of claim 36, wherein the non-MMAL variable focus lens is a variator, wherein the variator is configured to change the focusing property of the lens unit,

39. The optical tracking device of claim 1, wherein the lens unit further comprises a flat mirror.

40. The optical tracking device of claim 1, further comprising a mechanical movement unit, communicatively coupled to the image processing unit, configured to mechanically adjust attitude of the optical tracking device in response to the control signal in order to adjust the optical axis at the lens unit.

41. A method for detecting and tracking a target using an optical device comprising steps of:

capturing a scene image using a lens unit having at least one Micromirror Array Lens comprising a plurality of micromirrors and an imaging unit;

processing the scene image using an image processing unit and extracting target movement information;

generating a control signal; and

changing a focusing property of the Micromirror Array Lens by forming an optical surface profile of the Micromirror Mirror Array Lens by controlling motions of the micromirrors in the Micromirror Array Lens according to the control signal while the motions of micromirrors in the Micromirror Array Lens is controlled to correct aberration.

42. The method of claim 41, wherein the step of changing the focusing property of the Micromirror Array lens is for focusing a target image.

43. The method of claim 41, wherein the step of changing the focusing property of the Micromirror Array lens is for adjusting an effective focal length of the lens unit.

44. The method of claim 41, wherein the step of changing the focusing property of the Micromirror Array lens is for adjusting a field of view of the lens unit.

45. The method of claim 41, wherein the step of changing the focusing property of the Micromirror Array lens is for adjusting an optical axis of the lens unit.

46. The method of claim 41, wherein the step of changing the focusing property of the Micromirror Array lens is for adjusting a magnification of the lens unit.

47. The method of claim 41, further comprising;

measuring the distance between the lens unit and the target by extracting an in-focus target image from the scene image using the image processing unit.

48. The method of claim 41, further comprising:

measuring three-dimensional image information of the target by changing a focal plane of the lens unit by adjusting the effect focal length of the lens unit.

49. The method of claim 41, further comprising:

using a time-sharing technique with the optical device to obtain a wide field of view image and a narrow field of view image within a short time period.