Abstract: Systems and methods for enhancing spectral domain optical coherence tomography (OCT] are provided. In particular, a system and method for calibration of spectral interference signals using an acquired calibration signal are provided. The calibration signal may be logarithmically amplified to further improve the accuracy of the calibration. From the calibration signal, a series of more accurate calibration data are calculated. An acquired spectral interference signal is calibrated using these calibration data. Moreover, systems that include logarithmic amplification of the spectral interference signal and variable band-pass filtering of the spectral interference signal are provided. Such systems increase the dynamic range and visualization capabilities relative to conventional spectral domain OCT systems.

Abstract: An optical system and method for characterizing an object is provided. The system includes at least one light source configured to direct photons toward an object and an interferometer configured to receive photons from the object. The system also includes at least one detector system adapted to detect an optical signal at an output of the interferometer and to remove, from the detected optical signal, a signal portion representing first order photon correlations, when present. The system also includes a processor configured to receive data relating to second-order correlated photons from said at least one detector system, each photon or photon pair subject to at least two indistinguishable paths to a photon or photon pair, but differing in at least one of time and length. The processor is configured to characterize the object based on a self interference of the second-order correlated photons from a common location within the object.

Abstract: An optical system and method for characterizing an object is provided. The system includes at least one light source configured to direct photons toward an object and an interferometer configured to receive photons from the object. The system also includes at least one detector system adapted to detect an optical signal at an output of the interferometer and to remove, from the detected optical signal, a signal portion representing first order photon correlations, when present. The system also includes a processor configured to receive data relating to second-order correlated photons from said at least one detector system, each photon or photon pair subject to at least two indistinguishable paths to a photon or photon pair, but differing in at least one of time and length. The processor is configured to characterize the object based on a self interference of the second-order correlated photons from a common location within the object.

Abstract: Systems and methods for enhancing spectral domain optical coherence tomography (OCT] are provided. In particular, a system and method for calibration of spectral interference signals using an acquired calibration signal are provided. The calibration signal may be logarithmically amplified to further improve the accuracy of the calibration. From the calibration signal, a series of more accurate calibration data are calculated. An acquired spectral interference signal is calibrated using these calibration data. Moreover, systems that include logarithmic amplification of the spectral interference signal and variable band-pass filtering of the spectral interference signal are provided. Such systems increase the dynamic range and visualization capabilities relative to conventional spectral domain OCT systems.

Abstract: A fiber optic needle probe for measuring or imaging the internal structure of a specimen includes a needle defining a bore, an optical fiber substantially positioned within the bore, and a beam director in optical communication with the optical fiber. At least a portion of the wall of the needle is capable of transmitting light. The beam director directs light from the optical fiber to an internal structure being imaged and receives light from the structure through a transparent portion of the wall. An actuating device causes motion of any, or all of, the needle, optical fiber, and beam director to scan the internal structure of the specimen. The fiber optic needle probe allows imaging inside a solid tissue or organ without intraluminal insertion. When used in conjunction with an OCT imaging system, the fiber optic needle probe enables tomographic imaging of the microstructure of internal organs and tissues which were previously impossible to image in a living subject.

Abstract: An imaging system for performing optical coherence tomography includes an optical radiation source; a reference optical reflector; a first optical path leading to the reference optical reflector; and a second optical path coupled to an endoscopic unit. The endoscopic unit preferably includes an elongated housing defining a bore; a rotatable single mode optical fiber having a proximal end and a distal end positioned within and extending the length of the bore of the elongated housing; and an optical system coupled to the distal end of the rotatable single mode optical fiber, positioned to transmit the optical radiation from the single mode optical fiber to the structure and to transmit reflected optical radiation from the structure to the single mode optical fiber.

Abstract: An imaging system for performing optical coherence tomography includes an optical radiation source; a reference optical reflector; a first optical path leading to the reference optical reflector; and a second optical path coupled to an endoscopic unit. The endoscopic unit preferably includes an elongated housing defining a bore; a rotatable single mode optical fiber having a proximal end and a distal end positioned within and extending the length of the bore of the elongated housing; and an optical system coupled to the distal end of the rotatable single mode optical fiber, positioned to transmit the optical radiation from the single mode optical fiber to the structure and to transmit reflected optical radiation from the structure to the single mode optical fiber.