REFERENCE STRUCTURES AND REFERENCE STRUCTURE ENHANCED TOMOGRAPHY

• US 20100322372A1
• Filed: 12/12/2007
• Published: 12/23/2010
• Est. Priority Date: 09/30/2002
• Status: Active Grant

• Current Assignee: Duke University
• Original Assignee: Duke University
• Inventors: Brady, David Jones
• Granted Patent: US 7,912,173 B2
• Time in Patent Office: Days
• US Class Current: 378/4
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: G06T 11/005 Specific pre-processing for tomographic reconstruction, e.g. calibration, source positioning, rebinning, scatter correction, retrospective gating

Abstract

A reference structure tomography device is provided which includes a reference structure configured to intercept and modulate energy in the form of waves or otherwise propagating from a source to a sensor, along longitudinal and traverse directions. The reference structure modulates or otherwise conditions the propagating wave to simplify an inversion process on the data set created by the interaction between the wave and the sensors. The reference structure can modulate a wave through multiple types of interactions with the wave including obscuring, defracting, defusing, scattering, and otherwise altering any characteristic of a portion of the wave. By selecting a reference structure that is compatible with the sensors, the number of measurements needed to resolve the source through the source wave is reduced. The reference structure can also increase the resolution of an imaging system. Thus, by reducing or altering the data collected by the sensors, the reference structure tomography device can improve the imaging abilities of the system.

Claims

1. A source resolver, comprising:

a multi-dimensional reference structure configured to modulate source radiation in a predetermined manner to produce a reference structure modulated signal comprising a plurality of source space projections, the multi-dimensional reference structure comprises a longitudinal dimension and a transverse dimension, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the multi-dimensional reference structure modulates the source radiation along the longitudinal direction; and

an analyzer configured in accordance with said reference structure for resolving a source state from the reference structure modulated signal.

2. The source resolver of claim 1, wherein the source radiation comprises radiation generated by a source.

3. The source resolver of claim 1, wherein the source radiation comprises radiation scattered by a source.

4. The source resolver of claim 1, wherein the source radiation comprises radiation reflected by a source.

5. The source resolver of claim 1, wherein the source radiation propagates through a source.

6. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by attenuating a portion of the source radiation.

7. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by diffracting a portion of the source radiation.

8. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by scattering a portion of the source radiation.

9. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by refracting a portion of the source radiation.

10. The source wave resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by obscuring a portion of the source radiation.

11. The source resolver of claim 10, wherein the multi-dimensional reference structure comprises at least one aperture in a substantially opaque material, wherein the aperture is configured to pass a portion of the source radiation and the substantially opaque material is configured to obscure the source radiation.

12. The source resolver of claim 11, wherein the multi-dimensional reference structure comprises multiple apertures in a substantially opaque material, wherein at least two of the apertures overlap.

13. The source resolver of claim 12, wherein the multiple apertures comprise a first aperture defining a first plane and a second aperture defining a second plane, wherein the first and second planes are different.

14. The source resolver of claim 10, wherein the multi-dimensional reference structure comprises at least one channel in a substantially opaque material, wherein the channel is configured to pass a portion of the source radiation and the substantially opaque material is configured to substantially obscure a portion of the source radiation.

17. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by absorbing a portion of source radiation.

18. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by shifting a frequency of a portion of source radiation.

19. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by diffusing a portion of source radiation.

20. The source resolver of claim 1, wherein the multi-dimensional reference structure modulates the source radiation by reflecting a portion of source radiation.

21. The source resolver of claim 20, wherein the multi-dimensional reference structure comprises at least one mirror.

22. The source resolver of claim 21, wherein the multi-dimensional reference structure comprises at least one moveable mirror.

23. The source resolver of claim 22, wherein the multi-dimensional reference structure comprises an array of moveable mirrors.

24. The source resolver of claim 1, wherein the multi-dimensional reference structure comprises at least one sensor.

26. The source resolver of claim 1, wherein the multi-dimensional reference structure comprises a three-dimensional structure.

27. The source resolver of claim 1, wherein the analyzer comprises a sensor.

28. The source resolver of claim 27, wherein the sensor comprises a plurality of sensors.

29. The source resolver of claim 27, wherein the sensor comprises an array of sensors.

30. The source resolver of claim 29, wherein the array of sensors is substantially periodic.

31. The source resolver of claim 27, wherein the sensor comprises at least one sensor configured to detect at least one reference structure modulated signal parameter.

32. The source resolver of claim 31, wherein the at least one reference structure modulated signal parameter comprises amplitude.

33. The source resolver of claim 31, wherein the reference structure modulated signal parameter comprises phase.

34. The source resolver of claim 31, wherein the reference structure modulated signal parameter comprises frequency.

35. The source resolver of claim 31, wherein the reference structure modulated signal parameter comprises polarity.

36. The source resolver of claim 31, wherein the reference structure modulated signal parameter comprises dispersion.

37. The source resolver of claim 31, wherein the reference structure modulated signal parameter comprises carrier frequency.

38. The source resolver of claim 36, wherein the source radiation comprises wave packets and the at least one reference structure modulated signal parameter comprises a wavelength of an envelope of the wave packet.

39. The source resolver of claim 1, wherein the analyzer comprises a processor.

40. The source resolver of claim 1, wherein the multi-dimensional reference structure comprises an active reference structure coupled to a reference structure driver.

41. The source resolver of claim 40, wherein the reference structure driver is in communication with the analyzer.

42. The source resolver of claim 40, wherein the reference structure driver is in communication with the source.

43. The source resolver of claim 41, wherein the reference structure driver is configured to receive a feedback signal from the analyzer and output a control signal to the active reference structure.

44. The source resolver of claim 43, wherein the modulation of the source radiation by the active reference structure is variable in accordance with the control signal from the reference structure driver.

45. A tomography machine configured to image an object, comprising the source resolver of claim 1.

46. The source resolver of claim 1, wherein the plurality of source space projections are produced by the multi-dimensional reference structure in a single time step.

47. The source resolver of claim 1, wherein the plurality of source space projections are produced by the multi-dimensional reference structure without scanning of the multi-dimensional reference structure.

15. (canceled)

16. (canceled)

25. (canceled)

48. A source imager, comprising:

a multi-dimensional reference structure configured to modulate source radiation to produce a reference structure modulated signal comprising a plurality of source space projections, the multi-dimensional reference structure comprises a longitudinal dimension and a transverse dimension, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the multi-dimensional reference structure modulates the source radiation along the longitudinal direction;

a sensor array configured to detect the reference structure modulated signal; and

a processor coupled to the sensor array and configured to derive source information from the detected reference structure modulated signal.

49. The source imager of claim 48, wherein the source information comprises a state of the source.

50. The source imager of claim 48, wherein the source information comprises an image of the source.

51. The source imager of claim 48, wherein the plurality of source space projections are produced by the multi-dimensional reference structure in a single time step.

52. The source imager of claim 48, wherein the plurality of source space projections are produced by the multi-dimensional reference structure without scanning of the multi-dimensional reference structure.

53. The source imager of claim 48, wherein the multi-dimensional reference structure comprises a three-dimensional reference structure.

54. A tomographic apparatus, comprising:

a source;

a sensor;

a multi-dimensional reference structure between the source and the sensor for producing modulated radiation from source radiation, wherein the modulated radiation is received by the sensor and comprises a plurality of source space projections, the multi-dimensional reference structure comprises a longitudinal dimension and a transverse dimension, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the multi-dimensional reference structure modulates the source radiation along the longitudinal direction; and

an analyzer coupled to the sensor for analyzing the modulated radiation.

55. The apparatus of claim 54, wherein the plurality of source space projections are produced by the multi-dimensional reference structure in a single time step.

56. The apparatus of claim 54, wherein the plurality of source space projections are produced by the multi-dimensional reference structure without scanning of the multi-dimensional reference structure.

57. The apparatus of claim 54, wherein the multi-dimensional reference structure comprises a three-dimensional reference structure.

58. A method of enhancing a sensor, comprising:

altering radiation received by the sensor by inserting a multi-dimensional reference structure into a path of the radiation, wherein the altered radiation comprises a plurality of source space projections, the multi-dimensional reference structure comprises a longitudinal dimension and a transverse dimension, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the multi-dimensional reference structure modulates the source radiation along the longitudinal direction; and

analyzing the sensor'"'"'s response to the altered radiation.

59. The method of claim 58, wherein the plurality of source space projections are produced by the multi-dimensional reference structure in a single time step.

60. The method of claim 58, wherein the plurality of source space projections are produced by the multi-dimensional reference structure without scanning of the multi-dimensional reference structure.

61. The method of claim 58, wherein the multi-dimensional reference structure comprises a three-dimensional reference structure.

62. A sensor system, comprising:

a multi-dimensional reference structure configured to receive unconditioned data radiated from a source and to produce conditioned data comprising a plurality of source space projections, multi-dimensional reference structure comprises a longitudinal dimension and a transverse dimension, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the multi-dimensional reference structure receives unconditioned data radiated from the source and produces the conditioned data along the longitudinal direction;

a sensor configured to receive the conditioned data; and

an analyzer configured to invert the conditioned data received by the sensor.

63. The sensor system of claim 62, wherein producing conditioned data comprises creating a linear transformation between the unconditioned data and the conditioned data with the multi-dimensional reference structure.

64. The sensor system of claim 63, wherein the reference structure is configured to create a well-conditioned linear transformation.

65. The sensor system of claim 62, wherein the unconditioned data comprises space-time coding.

66. The sensor system of claim 62, wherein the multi-dimensional reference structure comprises a non-monotonic multi-dimensional object.

67. The sensor system of claim 62, wherein the plurality of source space projections are produced by the multi-dimensional reference structure in a single time step.

68. The sensor system of claim 62, wherein the plurality of source space projections are produced by the multi-dimensional reference structure without scanning of the multi-dimensional reference structure.

69. The sensor system of claim 62, wherein the multi-dimensional reference structure comprises a three-dimensional reference structure.

70. A measurement system, comprising:

a source configured to produce source modulated radiation;

a multi-dimensional reference structure comprising a longitudinal dimension and a transverse dimension for receiving the source modulated radiation and producing reference modulated wave radiation comprising a plurality of source space projections, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the multi-dimensional reference structure receives the source modulated radiation and produces the reference modulated wave radiation along the longitudinal direction; and

an analyzer in communication with the reference modulated radiation for analyzing the reference modulated radiation.

71. The system of claim 70, wherein the source modulated radiation is time modulated.

72. The system of claim 70, wherein the source modulated radiation is space modulated.

73. The system of claim 70, wherein the source modulated radiation is space-time modulated.

74. The system of claim 70, wherein the source modulated radiation comprises a controllably variable pattern.

75. The system of claim 70, wherein the source comprises a controllably variable filter.

76. The system of claim 75, wherein the controllably variable filter comprises an LCD (liquid crystal display).

77. The system of claim 70, wherein the plurality of source space projections are produced by the multi-dimensional reference structure in a single time step.

78. The system of claim 70, wherein the plurality of source space projections are produced by the multi-dimensional reference structure without scanning of the multi-dimensional reference structure.

79. The system of claim 70, wherein the multi-dimensional reference structure comprises a three-dimensional reference structure.

80. A method of resolving a source state, comprising:

modulating source radiation such that a plurality of source space projections are created in a parallel fashion using a multi-dimensional reference structure that comprises a longitudinal dimension and a transverse dimension, the multi-dimensional reference structure comprises at least two obscuring structures or apertures distributed in a longitudinal direction in a non-linear manner, and the source radiation is modulated along the longitudinal direction; and

resolving the source state using the plurality of source space projections.

81. The method of claim 80, wherein resolving the source state comprises reconstructing a source distribution.

82. The method of claim 80, wherein resolving the source state comprises determining a spatial position of the source.

83. The method of claim 80, wherein the source radiation is also modulated along a transverse direction.

84. The method of claim 83, wherein the source radiation is modulated with a multi-dimensional reference structure.

85. The method of claim 83, wherein the source radiation is modulated with a volumetric reference structure.

86. The method of claim 80, wherein the source radiation comprises electromagnetic radiation.

87. The method of claim 80, wherein the source radiation comprises acoustic radiation.

88. The method of claim 80, wherein does source radiation comprises optical radiation.