Apparatus and method for ranging and noise reduction of low coherence interferometry LCI and optical coherence tomography OCT signals by parallel detection of spectral bands

• US 7,355,716 B2
• Filed: 01/24/2003
• Issued: 04/08/2008
• Est. Priority Date: 01/24/2002
• Status: Expired due to Term

• Current Assignee: General Hospital Corporation
• Original Assignee: The General Hospital Corporation (Mass General Brigham, Inc.)
• Inventors: Tearney, Guillermo J., de Boer, Johannes F., Bouma, Brett E.
• Primary Examiner(s): CONNOLLY, PATRICK J
• Application Number:
  US10/501,276
• Publication Number:
  US 20050018201A1
• Time in Patent Office: 1,901 Days
• Field of Search: 356/479, 356/497
• US Class Current: 356/479
• CPC Class Codes: A61B 5/0059 using light, e.g. diagnosis by transillumination, diascopy, fluorescence A61B5/0093, A61B5/1455, A61B5/02416 and A61B5/0261 take precedence
• CPC Class Codes: A61B 5/0066 Optical coherence imaging
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: G01B 2290/45 Multiple detectors for detecting interferometer signals
• CPC Class Codes: G01B 9/02007 Two or more frequencies or sources used for interferometric measurement using only beat G01B9/02003
• CPC Class Codes: G01B 9/02008 by using a frequency comb
• CPC Class Codes: G01B 9/0201 using temporal phase variation
• CPC Class Codes: G01B 9/02032 generating a spatial carrier frequency, e.g. by creating lateral or angular offset between reference and object beam shearing interferometers G01B9/02098
• CPC Class Codes: G01B 9/02044 Imaging in the frequency domain, e.g. by using a spectrometer
• CPC Class Codes: G01B 9/02045 using the Doppler effect
• CPC Class Codes: G01B 9/02079 Quadrature detection, i.e. detecting relatively phase-shifted signals
• CPC Class Codes: G01B 9/0209 Low-coherence interferometers
• CPC Class Codes: G01B 9/02091 Tomographic interferometers, e.g. based on optical coherence
• CPC Class Codes: G01N 21/4795 spatially resolved investigating of object in scattering medium in vivo A61B

Abstract

Apparatus, method, logic arrangement and storage medium are provided for increasing the sensitivity in the detection of optical coherence tomography and low coherence interferometry (“LCI”) signals by detecting a parallel set of spectral bands, each band being a unique combination of optical frequencies. The LCI broad bandwidth source can be split into N spectral bands. The N spectral bands can be individually detected and processed to provide an increase in the signal-to-noise ratio by a factor of N. Each spectral band may be detected by a separate photo detector and amplified. For each spectral band, the signal can be band p3 filtered around the signal band by analog electronics and digitized, or, alternatively, the signal may be digitized and band pass filtered in software. As a consequence, the shot noise contribution to the signal is likely reduced by a factor equal to the number of spectral bands, while the signal amplitude can remain the same. The reduction of the shot noise increases the dynamic range and sensitivity of the system.

Claims

1. An apparatus for optical imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a non-reflective reference

at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation or a combination of the first and second electro-magnetic radiation into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector configured to detect at least a portion of at least one of the frequency components,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

2. The apparatus according to claim 1, wherein the non-reflective reference is a transmissive reference.

3. The apparatus according to claim 1, further comprising at least one polarization controller.

4. The apparatus according to claim 1, further comprising at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation and the second electro-magnetic radiation.

5. The apparatus according to claim 1, further comprising:

a source generating a third electro-magnetic radiation; and

at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and the third electro-magnetic radiation.

6. The apparatus according to claim 1, further comprising:

a source generating a third electromagnetic radiation; and

a splitter configured to separate the third electro-magnetic radiation into a fourth electro-magnetic radiation directed to the reference and a fifth electro-magnetic radiation directed to the sample.

7. The apparatus according to claim 6, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

8. The apparatus according to claim 1, further comprising a splitter configured to combine the first and second electro-magnetic radiations.

9. The apparatus according to claim 8, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

10. The apparatus according to claim 1, wherein the detectors comprise at least one of (i) at least one single-dimensional detector array, and (ii) at least one multi-dimensional detector array.

11. The apparatus according to claim 1, wherein the spectral separating unit comprises at least one of (i) at least one reflection grating, (ii) at least one transmission grating, and (iii) at least one spectrally dispersive component.

12. The apparatus according to claim 1, further comprising at least one charge coupled device coupled to the at least one detection arrangement.

13. The apparatus according to claim 1, further comprising at least one bandpass filter coupled to the at least one detection arrangement.

14. The apparatus according to claim 13, wherein the bandpass filter is an electronic bandpass filter.

15. The apparatus according to claim 1, further comprising at least one analog to digital converter coupled to the at least one detection arrangement.

16. The apparatus according to claim 1, further comprising at least one processing arrangement receiving information which is at least partially based on the at least one of the frequency components.

17. The apparatus according to claim 1, further comprising at least one acousto-optic modulator coupled to the at least one detection arrangement.

18. The apparatus according to claim 1, wherein the detection arrangement generates at least one signal based on the frequency components and reduces noise of the at least one signal.

19. The apparatus according to claim 1, wherein the detection arrangement is configured to receive at least two electro-magnetic radiations, and detect a polarization state of at least one of the electro-magnetic radiations.

20. The apparatus according to claim 19, wherein the received electro-magnetic radiations are generated by splitting a combination of the first and second electro-magnetic radiations using a polarization-sensitive arrangement.

21. The apparatus according to claim 19, wherein a first one of the at least two of the detectors receives a first signal which has a first polarization of at least one of the first and second electro-magnetic radiations, and a second one of at least two of the detectors receives a second signal which has a second polarization of at least one of the first and second electro-magnetic radiations, the first and second polarization being different from one another.

22. The apparatus according to claim 1, further comprising:

at least one first arrangement detecting a signal relating to the first and second electro-magnetic radiations, and determining a relative phase difference between the first and second electro-magnetic radiations; and

at least one second arrangement controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second electro-magnetic radiations.

23. The apparatus according to claim 22, wherein the second arrangement controls a phase of at least one of the first and second electro-magnetic radiations.

24. The apparatus according to claim 22, wherein the second arrangement maximizes a signal-to-noise ratio of a signal associated with the at least one image.

25. An apparatus for optical imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a non-reflective

at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and a combination of the first and second electro-magnetic radiation into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector configured to detect at least a portion of at least one of the frequency components,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another, and

wherein at least two of the detectors detect a common one of the frequency components, wherein a first one of the at least two of the detectors receives a first signal which has a first phase difference between the first and second electro-magnetic radiation, and a second one of at least two of the detectors receives a second signal which has a second phase difference between the first and second electro-magnetic radiation, the first and second phase differences being different from one another.

26. The apparatus according to claim 25, wherein the first and second ones of the detectors detect the common one of the frequency components in an approximately simultaneous manner.

27. The apparatus according to claim 25, wherein the first and second phase differences are different from one another by approximately periodic of at least one of 15, 30, 45, 60, 75, 90 and 180 degrees.

28. A method for optical imaging, comprising the steps of:

receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a non-reflective reference;

separating spectrum of at least one of the first electro-magnetic radiation or a combination of the first and second light signals into frequency components; and

causing at least one detection of at least a portion of at least one of the frequency components using a plurality of detectors,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

29. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and combination of the first and second electro-magnetic radiations into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector configured to detect at least a portion of at least one of the frequency components, wherein at least two of the detectors detect a common one of the frequency components, wherein a first one of the at least two of the detectors receives a first signal which has a first phase difference between the first and second electro-magnetic radiation, and a second one of at least two of the detectors receives a second signal which has a second phase difference between the first and second electro-magnetic radiation, the first and second phase differences being different from one another,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

30. The apparatus according to claim 29, wherein the first and second ones of the detectors detect the common one of the frequency components in an approximately simultaneous manner.

31. The apparatus according to claim 29, wherein the first and second phase differences are different from one another by approximately periodic of at least one of 15, 30, 45, 60, 75, 90 and 180 degrees.

32. The apparatus according to claim 29, wherein the reference is a transmissive reference.

33. The apparatus according to claim 29, further comprising at least one polarization controller.

34. The apparatus according to claim 29, further comprising at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation and the second electro-magnetic radiation.

35. The apparatus according to claim 29, further comprising:

a source generating a third electro-magnetic radiation; and

at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and the third electro-magnetic radiation.

36. The apparatus according to claim 29, further comprising:

a source generating a third electromagnetic radiation; and

a splitter configured to separate the third electro-magnetic radiation into a fourth electro-magnetic radiation directed to the reference and a fifth electro-magnetic radiation directed to the sample, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

37. The apparatus according to claim 36, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

38. The apparatus according to claim 29, further comprising a splitter configured to combine the first and second electro-magnetic radiations, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

39. The apparatus according to claim 38, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

40. The apparatus according to claim 29, wherein the detectors comprise at least one of (i) at least one single-dimensional detector array, and (ii) at least one multi-dimensional detector array.

41. The apparatus according to claim 29, wherein the spectral separating unit comprises at least one of (i) at least one reflection grating, (ii) at least one transmission grating, and (iii) at least one spectrally dispersive component.

42. The apparatus according to claim 29, further comprising at least one charge coupled device coupled to the at least one detection arrangement.

43. The apparatus according to claim 29, further comprising at least one bandpass filter coupled to the at least one detection arrangement.

44. The apparatus according to claim 43, wherein the bandpass filter is an electronic bandpass filter.

45. The apparatus according to claim 29, further comprising at least one analog to digital converter coupled to the at least one detection arrangement.

46. The apparatus according to claim 29, further comprising at least one processing arrangement receiving information which is at least partially based on the at least one of the frequency components.

47. The apparatus according to claim 29, further comprising at least one acousto-optic modulator coupled to the at least one detection arrangement.

48. The apparatus according to claim 29, wherein the reference is non-reflective.

49. The apparatus according to claim 29, wherein the detection arrangement generates at least one signal based on the frequency components and reduces noise of the at least one signal.

50. The apparatus according to claim 29, wherein the detection arrangement is configured to receive at least two electro-magnetic radiations, and detect a polarization state of at least one of the electro-magnetic radiations.

51. The apparatus according to claim 50, wherein the received electro-magnetic radiations are generated by splitting a combination of the first and second electro-magnetic radiations using a polarization-sensitive arrangement.

52. The apparatus according to claim 29, wherein a first one of the at least two of the detectors receives a first signal which has a first polarization of at least one of the first and second electro-magnetic radiations, and a second one of at least two of the detectors receives a second signal which has a second polarization of at least one of the first and second electro-magnetic radiations, the first and second polarizations being different from one another.

53. The apparatus according to claim 29, further comprising:

at least one first arrangement detecting a signal relating to the first and second electro-magnetic radiations, and determining a relative phase difference between the first and second electro-magnetic radiations; and

at least one second arrangement controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second electro-magnetic radiations.

54. The apparatus according to claim 53, wherein the second arrangement controls a phase of at least one of the first and second electro-magnetic radiations.

55. The apparatus according to claim 53, wherein the second arrangement maximizes a signal-to-noise ratio of a signal associated with the at least one image.

56. A method for imaging, comprising:

receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

separating spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and combination of the first and second electro-magnetic radiations into frequency components; and

causing at least one detection of at least a portion of at least one of the frequency components using a plurality of detectors, wherein at least two of the detectors detect a common one of the frequency components, wherein a first one of the at least two of the detectors receives a first signal which has a first phase difference between the first and second electro-magnetic radiation, and a second one of at least two of the detectors receives a second signal which has a second phase difference between the first and second electro-magnetic radiation, the first and second phase differences being different from one another,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

57. The apparatus according to claim 56, wherein the first and second phase differences are different from one another by approximately periodic of at least one of 15, 30, 45, 60, 75, 90 and 180 degrees.

58. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation or a combination of the first and second electro-magnetic radiations into frequency components; and

at least one detection arrangement including at least three detectors, each of the detectors configured to detect at least a portion of at least one of the frequency components, wherein the detection arrangement generates at least one signal based on the frequency components and reduces noise of the at least one signal,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

59. The apparatus according to claim 58, wherein the reference is a transmissive reference.

60. The apparatus according to claim 58, further comprising at least one polarization controller.

61. The apparatus according to claim 58, further comprising at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation and the second electro-magnetic radiation.

62. The apparatus according to claim 58, further comprising:

a source generating a third electro-magnetic radiation; and

at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and the third electro-magnetic radiation.

63. The apparatus according to claim 58, further comprising:

a source generating a third electromagnetic radiation; and

a splitter configured to separate the third electro-magnetic radiation into a fourth electro-magnetic radiation directed to the reference and a fifth electro-magnetic radiation directed to the sample, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

64. The apparatus according to claim 63, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

65. The apparatus according to claim 58, further comprising a splitter configured to combine the first and second electro-magnetic radiations, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

66. The apparatus according to claim 65, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

67. The apparatus according to claim 58, wherein the detectors comprise at least one of (i) at least one single-dimensional detector array, and (ii) at least one multi-dimensional detector array.

68. The apparatus according to claim 58, wherein the spectral separating unit comprises at least one of (i) at least one reflection grating, (ii) at least one transmission grating, and (iii) at least one spectrally dispersive component.

69. The apparatus according to claim 58, further comprising at least one charge coupled device coupled to the at least one detection arrangement.

70. The apparatus according to claim 58, further comprising at least one bandpass filter coupled to the at least one detection arrangement.

71. The apparatus according to claim 70, wherein the bandpass filter is an electronic bandpass filter.

72. The apparatus according to claim 58, further comprising at least one analog to digital converter coupled to the at least one detection arrangement.

73. The apparatus according to claim 58, further comprising at least one processing arrangement receiving information which is at least partially based on the at least one of the frequency components.

74. The apparatus according to claim 58, further comprising at least one acousto-optic modulator coupled to the at least one detection arrangement.

75. The apparatus according to claim 58, wherein the reference is non-reflective.

76. The apparatus according to claim 58, wherein the detection arrangement is configured to receive at least two electro-magnetic radiations, and detect a polarization state of at least one of the electro-magnetic radiations.

77. The apparatus according to claim 76, wherein the received electro-magnetic radiations are generated by splitting a combination of the first and second electro-magnetic radiations using a polarization-sensitive arrangement.

78. The apparatus according to claim 76, wherein a first one of the at least two of the detectors receives a first signal which has a first polarization of at least one of the first and second electro-magnetic radiations, and a second one of at least two of the detectors receives a second signal which has a second polarization of at least one of the first and second electro-magnetic radiations, the first and second polarization being different from one another.

79. The apparatus according to claim 58, further comprising:

at least one first arrangement detecting a signal relating to the first and second electro-magnetic radiations, and determining a relative phase difference between the first and second electro-magnetic radiations; and

at least one second arrangement controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second arms.

80. The apparatus according to claim 79, wherein the second arrangement controls a phase of at least one of the first and second electro-magnetic radiations.

81. The apparatus according to claim 79, wherein the second arrangement maximizes a signal-to-noise ratio of a signal associated with the at least one image.

82. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and a combination of the first and second electro-magnetic radiations into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector configured to detect at least a portion of at least one of the frequency components, wherein the detection arrangement generates at least one signal based on the frequency components and reduces noise of the at least one signal,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another, and

wherein at least two of the detectors detect the common one of the frequency components in an approximately simultaneous manner.

83. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

at least one of spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation or a combination of the first and second electro-magnetic radiations into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector configured to detect at least a portion of at least one of the frequency components, wherein the detection arrangement is configured to receive at least two electro-magnetic radiations and detect a polarization state of at least one of the electro-magnetic radiations,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

84. The apparatus according to claim 83, wherein the reference is a transmissive reference.

85. The apparatus according to claim 83, further comprising at least one polarization controller.

86. The apparatus according to claim 83, further comprising at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation and the second electro-magnetic radiation.

87. The apparatus according to claim 83, further comprising:

a source generating a third electro-magnetic radiation; and

at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and the third electro-magnetic radiation.

88. The apparatus according to claim 83, further comprising:

a source generating a third electromagnetic radiation; and

a splitter configured to separate the third electro-magnetic radiation into a fourth electro-magnetic radiation directed to the reference and a fifth electro-magnetic radiation directed to the sample, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

89. The apparatus according to claim 88, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

90. The apparatus according to claim 83, further comprising a splitter configured to combine the first and second electro-magnetic radiations, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

91. The apparatus according to claim 90, wherein the splitter is at least one of a fiberoptic splitter and a bulk optic splitter.

92. The apparatus according to claim 83, wherein the detectors comprise at least one of (i) at least one single-dimensional detector array, and (ii) at least one multi-dimensional detector array.

93. The apparatus according to claim 83, wherein the spectral separating unit comprises at least one of (i) at least one reflection grating, (ii) at least one transmission grating, and (iii) at least one spectrally dispersive component.

94. The apparatus according to claim 83, further comprising at least one charge coupled device coupled to the at least one detection arrangement.

95. The apparatus according to claim 83, further comprising at least one bandpass filter coupled to the at least one detection arrangement.

96. The apparatus according to claim 95, wherein the bandpass filter is an electronic bandpass filter.

97. The apparatus according to claim 83, further comprising at least one analog to digital converter coupled to the at least one detection arrangement.

98. The apparatus according to claim 83, further comprising at least one processing arrangement receiving information which is at least partially based on the at least one of the frequency components.

99. The apparatus according to claim 83, further comprising at least one acousto-optic modulator coupled to the at least one detection arrangement.

100. The apparatus according to claim 83, wherein the reference is non-reflective.

101. The apparatus according to claim 83, wherein the received electro-magnetic radiations are generated by splitting a combination of the first and second electro-magnetic radiations using a polarization-sensitive arrangement.

102. The apparatus according to claim 83, wherein a first one of the at least two of the detectors receives a first signal which has a first polarization of at least one of the first and second electro-magnetic radiations, and a second one of at least two of the detectors receives a second signal which has a second polarization of at least one of the first and second electro-magnetic radiations, the first and second polarization being different from one another.

103. The apparatus according to claim 83, further comprising:

at least one first arrangement detecting a signal relating to the first and second electro-magnetic radiations, and determining a relative phase difference between the first and second electro-magnetic radiations; and

at least one second arrangement controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second arms.

104. The apparatus according to claim 103, wherein the second arrangement controls a phase of at least one of the first and second electro-magnetic radiations.

105. The apparatus according to claim 103, wherein the second arrangement maximizes a signal-to-noise ratio of a signal associated with the at least one image.

106. The apparatus according to claim 83, wherein the detectors are provided as a single detection array.

107. The apparatus according to claim 83, wherein the polarization state of the at least one first electro-magnetic radiation is determined from the at least one of the at least two electro-magnetic radiations received by the detectors.

108. The apparatus according to claim 83, wherein the polarization state of the at least one first electro-magnetic radiation is determined from at least one of an amplitude and a phase difference of the at least one of the at least two electro-magnetic radiations received by the detectors.

109. The apparatus according to claim 103, wherein the phase difference is determined from an amplitude of electro-magnetic radiations received by the detectors.

110. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

at least one of spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and a combination of the first and second electro-magnetic radiations into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector configured to detect at least a portion of at least one of the frequency components, wherein the detection arrangement is configured to receive at least two electro-magnetic radiations and detect a polarization state of at least one of the electro-magnetic radiations,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another, and

wherein at least two of the detectors detect the common one of the frequency components in an approximately simultaneous manner.

111. A method for imaging, comprising:

receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

separating spectrum of at least one of the first electro-magnetic radiation or combination of the first and second electro-magnetic radiations into frequency components; and

causing at least one detection of at least a portion of at least one of the frequency components using at least one detection arrangement, wherein the detection arrangement is configured to receive at least two electro-magnetic radiations and detect a polarization state of at least one of the electro-magnetic radiations,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

112. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a first arm and at least one second electro-magnetic radiation from a second arm;

at least one first arrangement detecting a signal relating to the first and second electro-magnetic radiations, and determining a relative phase difference between the first and second electro-magnetic radiations;

at least one of spectral separating arrangement which separates spectrum of a combination of the first and second electro-magnetic radiations into frequency components; and

at least one second arrangement controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second arms,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

113. The apparatus according to claim 112, wherein the first arm is a transmissive reference.

114. The apparatus according to claim 112, further comprising at least one polarization controller.

115. The apparatus according to claim 112, further comprising at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation and the second electro-magnetic radiation.

116. The apparatus according to claim 112, further comprising:

a source generating a third electro-magnetic radiation; and

at least one polarization modulator which is positioned in a path of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and the third electro-magnetic radiation.

117. The apparatus according to claim 112, wherein at least one of the first and second arrangement comprise at least one of (i) at least one single-dimensional detector array, and (ii) at least one multi-dimensional detector array.

118. The apparatus according to claim 112, further comprising a spectral separating unit which is at least one of (i) at least one reflection grating, (ii) at least one transmission grating, and (iii) at least one spectrally dispersive component.

119. The apparatus according to claim 112, further comprising at least one charge coupled device coupled to at least one of the first and second arrangements.

120. The apparatus according to claim 112, further comprising at least one bandpass filter coupled to at least one of the first and second arrangements.

121. The apparatus according to claim 120, wherein the band pass filter is an electronic bandpass filter.

122. The apparatus according to claim 112, further comprising at least one analog to digital converter coupled to at least one of the first and second arrangements.

123. The apparatus according to claim 122, further comprising at least one processing arrangement receiving information which is at least partially based on at least one of the frequency components.

124. The apparatus according to claim 112, further comprising at least one acousto-optic modulator coupled to the at least one detection arrangement.

125. The apparatus according to claim 112, wherein the first arm is a non-reflective reference.

126. The apparatus according to claim 112, wherein at least one of the first and second arrangement is configured to receive at least two electro-magnetic radiations, and detecting a polarization state of at least one of the electro-magnetic radiations.

127. The apparatus according to claim 126, wherein the received electro-magnetic radiations are generated by splitting a combination of the first and second electro-magnetic radiations using a polarization-sensitive arrangement.

128. The apparatus according to claim 126, wherein a first one of the at least two of the detectors receives a first signal which has a first polarization of at least one of the first and second electro-magnetic radiations, and a second one of at least two of the detectors receives a second signal which has a second polarization of at least one of the first and second electro-magnetic radiations, the first and second polarization being different from one another.

129. The apparatus according to claim 112, wherein the second arrangement controls a phase of at least one of the first and second electro-magnetic radiations.

130. The apparatus according to claim 112, wherein the second arrangement maximizes a signal-to-noise ratio of a signal associated with the at least one image.

131. An apparatus for imaging, comprising:

a device receiving at least one first electro-magnetic radiation from a first arm and at least one second electro-magnetic radiation from a second arm;

at least one first arrangement detecting a signal relating to the first and second electro-magnetic radiations, and determining a relative phase difference between the first and second electro-magnetic radiations;

at least one second arrangement controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second arms, wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. frequency components of the first and second electro-magnetic radiations interfere with one another; and

a plurality of detectors detecting a common one of the frequency components of the first and second electro-magnetic radiations in an approximately simultaneous manner.

132. A method for imaging, comprising:

receiving at least one first electro-magnetic radiation from a first arm and at least one second electro-magnetic radiation from a second arm;

detecting a signal relating to the first and second electro-magnetic radiations;

separating spectrum of a combination of the first and second light signals into frequency components;

determining a relative phase difference between the first and second electro-magnetic radiations; and

controlling at least one of the first and second electro-magnetic radiations based on the relative phase difference so as to facilitate a generation of at least one image associated with at least one of the first and second arms,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

133. A storage medium including executable instructions thereon for tracking a phase of at least one electro-magnetic signal so as to reduce an attenuation of the at least one signal due to its fringe instability, wherein, when the executable instructions are executed by a processing system, the executable instructions configure the processing system to perform the steps comprising of:

a. obtaining first data associated with at least one first interferometric signal comprising a plurality of spectral bands separated from the at least one electro-magnetic signal;

b. causing a modulation of the at least one first signal based on a modulating frequency of a modulating arrangement so as to generate at least one second signal;

c. causing a mixing of the at least one first signal with the at least one second signal so as to generate a resultant signal;

d. generating second data associated with an offset based on the resultant signal;

e. controlling a phase of the at least one first signal based on the offset to generate further information; and

f. generating an image based on at least a portion of the sample using the further information.

134. A probe for locating atherosclerotic plaque in a blood vessel, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a non-reflective reference;

at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation or a combination of the first and second electro-magnetic radiation into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector being configured to detect at least a portion of at least one of the frequency components,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

135. A probe for locating atherosclerotic plaque in a blood vessel, comprising:

a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference;

at least one of spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and combination of the first and second electro-magnetic radiations into frequency components; and

at least one detection arrangement including a plurality of detectors, each detector being configured to detect at least a portion of at least one of the frequency components, wherein at least two of the detectors detect a common one of the frequency components, wherein a first one of the at least two of the detectors receives a first signal which has a first phase difference between the first and second electro-magnetic radiation, and a second one of at least two of the detectors receives a second signal which has a second phase difference between the first and second electro-magnetic radiation, the first and second phase differences being different from one another,

wherein at least one of;

a. the first and second electro-magnetic radiations interfere with one another, and

b. the frequency components of the first and second electro-magnetic radiations interfere with one another.

136. An apparatus for delivering a therapeutic agent, comprising:

a) a probe disposed in a housing and comprising;

i. a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a non-reflective reference;

ii. at least one spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation or a combination of the first and second electro-magnetic radiation into frequency components; and

iii. at least one detection arrangement including a plurality of detectors, each detector being configured to detect at least a portion of at least one of the frequency components,

wherein at least one of;

(I) the first and second electro-magnetic radiations interfere with one another, and

(II) the frequency components of the first and second electro-magnetic radiations interfere with one another; and

b) a conduit cooperating with the probe, and comprising a proximal end for receiving the therapeutic agent and a distal end for delivering the therapeutic agent at a predetermined location, the location being determined by imaging an environment in proximity to the distal end using the probe.

137. An apparatus for delivering a therapeutic agent, comprising:

a) a probe disposed in the housing and comprising;

i. a device receiving at least one first electro-magnetic radiation from a sample and at least one second electro-magnetic radiation from a reference,

ii. at least one of spectral separating unit which separates spectrum of at least one of the first electro-magnetic radiation, the second electro-magnetic radiation and combination of the first and second electro-magnetic radiations into frequency components, and

iii. at least one detection arrangement including a plurality of detectors, each detector being configured to detect at least a portion of at least one of the frequency components, wherein at least two of the detectors detect a common one of the frequency components, wherein a first one of the at least two of the detectors receives a first signal which has a first phase difference between the first and second electro-magnetic radiation, and a second one of at least two of the detectors receives a second signal which has a second phase difference between the first and second electro-magnetic radiation, the first and second phase differences being different from one another,

wherein at least one of;

(I) the first and second electro-magnetic radiations interfere with one another, and

(II) the frequency components of the first and second electro-magnetic radiations interfere with one another; and

b) a conduit cooperating with the probe, and comprising a proximal end for receiving the therapeutic agent and a distal end for delivering the therapeutic agent at a predetermined location, the location being determined by imaging the environment in proximity to the distal end using the probe.