Abstract: Variants of an interferometric device are developed for examining internal structures of objects by means of optical coherence tomography, which allow for controlling a boundary location of the observation range. The device also allows for correcting a distortion of the tomographic image of the object under study, caused by lateral scanning, due to aberrations of the optical path length for the low-coherence optical radiation directed towards the object. Embodiments of the device include either one, or two fiber-optic controlled scanners, which in different combinations perform a function of in-depth scanning of the coherence window of low-coherence optical radiation within the observation range, a function of controlling a boundary location of the observation range, and a function of compensating the optical path length aberration for the low-coherence optical radiation directed towards the object, caused by lateral scanning.

Abstract: Polarization sensitive common path OCT/OCR devices are presented. Optical radiation from a source is converted into two cross-polarized replicas propagating therethrough with a predetermined optical path length difference. The two cross-polarized replicas are then delivered to an associated sample by a delivering device, which is, preferably, an optical fiber probe. A combination optical radiation is produced in at least one secondary interferometer by combining a corresponding portion of an optical radiation returning from the associated sample with a reference optical radiation reflected from a tip of an optical fiber of the optical fiber probe. Subject to a preset optical path length difference of the arms of the at least one secondary interferometer, a cross-polarized component, and/or a parallel-polarized component of the combined optical radiation, are selected. The topology of the devices allows for time domain, as well as for frequency domain registration.

Abstract: Variants of an interferometric device are developed for examining internal structures of objects by means of optical coherence tomography, which allow for controlling a boundary location of the observation range. The device also allows for correcting a distortion of the tomographic image of the object under study, caused by lateral scanning, due to aberrations of the optical path length for the low-coherence optical radiation directed towards the object. Embodiments of the device include either one, or two fiber-optic controlled scanners, which in different combinations perform a function of in-depth scanning of the coherence window of low-coherence optical radiation within the observation range, a function of controlling a boundary location of the observation range, and a function of compensating the optical path length aberration for the low-coherence optical radiation directed towards the object, caused by lateral scanning.

Abstract: Common path frequency domain optical coherence reflectometry/tomography devices include a portion of optical fiber with predetermined optical properties adapted for producing two eigen modes of the optical radiation propagating therethrough with a predetermined optical path length difference. The two replicas of the optical radiation outgoing from the portion of the optical fiber are then delivered to an associated sample by an optical fiber probe. The tip of the optical fiber serves as a reference reflector and also serves as a combining element that produces a combination optical radiation by combining an optical radiation returning from the associated sample with a reference optical radiation reflected from the reference reflector. The topology of the devices allows for registering a cross-polarized or a parallel-polarized component of the optical radiation reflected or backscattered from the associated sample.

Abstract: Common path frequency domain optical coherence reflectometry/tomography devices with an additional interferometer are suggested. The additional interferometer offset is adjusted such, that it is ether less than the reference offset, or exceeds the distance from the reference reflector to the distal boundary of the longitudinal range of interest. This adjustment allows for relieving the requirements to the spectral resolution of the frequency domain optical coherence reflectometry/tomography engine and/or speed of the data acquisition and processing system, and eliminates depth ambiguity problems. The new topology allows for including a phase or frequency modulator in an arm of the additional interferometer improving the signal-to-noise ratio of the devices. The modulator is also capable of substantially eliminating mirror ambiguity, DC artifacts, and autocorrelation artifacts. The interference signal is produced either in the interferometer or inside of the optical fiber probe leading to the sample.

Abstract: The present invention relates to an optical fiber magnetic scanning arrangement for a miniature optical fiber probe and can be applied for optical beam delivery in various optical imaging techniques. The arrangement is of the type where an optical fiber is rigidly fixed to a current conductor and serving as a flexible cantilever with a capability for the distal part of the optical fiber of being deflected in a direction substantially orthogonal to its own axis. New designs of the magnetic system are less critical to the shape and dimensional tolerances of scanner elements and assembly. These designs provide a potential for a less difficult assembly process and for further miniaturization. According to one aspect of the invention the permanent magnet system includes at least a first permanent magnet with a magnetization direction that is substantially aligned with the own axis of the optical fiber. The current conductor loop is placed adjacent to the one of the end faces of the first permanent magnet.

Abstract: The present invention relates to the study of internal structure of objects by optical means. The invention presents a bi-directional sampling optical path for the low coherent optical radiation directed to the sample, i.e. a bi-directional sampling arm, and two unidirectional reference beams directed along a reference path designed as a loop. One of the reference beams propagates clockwise and the other propagates counterclockwise in the reference loop. The beam splitters non-reciprocal or polarization-dependent and by placing polarization-changing elements between the beam splitters and/or into the sampling arm and the reference loop. Thus the developed method and optical interferometer make possible to ensure highly efficient use of optical source power together with optimal signal-to-noise ratio for a given optical source power and are simple and cost effective.

Abstract: In a method for in vivo diagnostics of a biological tissue covered with epithelium an image of the biological tissue is acquired with the aid of a beam in the visible or near IR range directed towards a biological tissue by visualizing the intensity of optical radiation backscattered by the biological tissue. The basal membrane of said biological tissue, which separates the epithelium from an underlying stroma, is identified in the acquired image and diagnostics is performed on basis of the form of the basal membrane. For diagnostics of biological tissue lining the surface of cavities and internal organs of a patient a miniature optical fiber probe is inserted into the patient's cavity. The probe may be placed at a distal end of an endoscope instrumental channel.

Abstract: The present invention relates to the analysis of the internal structures of objects using optical means. According to the invention there were designed an apparatus suited for optical coherence tomography (OCT), an optical fiber lateral scanner (15), which is a part of said apparatus and is incorporated into an optical fiber probe (8), and a method for studying biological tissue in vivo, which allows for making a diagnostics of the biological tissue under study on basis of the state of the basal membrane (46). The moving part of lateral scanner (15) of sampling arm (4) of interferometer (2) is arranged comprising a current conductor (19), which envelopes a magnetic system (17) in the area of one of its poles (25) and an optical fiber (13), which is rigidly fastened to current conductor (19), whereas optical fiber (13) serves as a flexible cantilever, allowing to miniaturize the optical fiber probe (8).

Abstract: The present invention relates to the analysis of the internal structures of objects using optical means. According to the invention there were designed an apparatus suited for optical coherence tomography (OCT), an optical fiber lateral scanner (15), which is a part of said apparatus and is incorporated into an optical fiber probe (8), and a method for studying biological tissue in vivo, which allows for making a diagnostics of the biological tissue under study on basis of the state of the basal membrane (46). The moving part of lateral scanner (15) of sampling arm (4) of interferometer (2) is arranged comprising a current conductor (19), which envelopes a magnetic system (17) in the area of one of its poles (25) and an optical fiber (13), which is rigidly fastened to current conductor (19), whereas optical fiber (13) serves as a flexible cantilever, allowing to miniaturize the optical fiber probe (8).

Abstract: The present invention relates to the study of internal structure of objects by optical means. One modification of the invention presents a bi-directional optical path for the low coherent optical radiation directed to the sample, i.e. a bi-directional sampling arm, and a unidirectional optical path for the low coherent reference optical radiation, i.e. a unidirectional reference arm. This makes splitting and mixing ratios completely independent, the latter providing for optimal power management. Another modification of the invention presents a bi-directional optical path for the low coherent optical radiation directed to the sample, i.e. a bi-directional sampling arm, and two unidirectional reference beams directed along a reference path designed as a loop. One of the reference beams propagates clockwise and the other propagates counterclockwise in the reference loop.

Abstract: The present invention relates to the analysis of the internal structures of objects using optical means. According to the invention there were designed an apparatus suited for optical coherence tomography (OCT), an optical fiber lateral scanner (15), which is a part of said apparatus and is incorporated into an optical fiber probe (8), and a method for studying biological tissue in vivo, which allows for making a diagnostics of the biological tissue under, study on basis of the state of the basal membrane (46). The moving part of lateral scanner (15) of sampling arm (4) of interferometer (2) is arranged comprising a current conductor (19), which envelopes a magnetic system (17) in the area of one of its poles (25) and an optical fiber (13), which is rigidly fastened to current conductor (19), whereas optical fiber (13) serves as a flexible cantilever, allowing to miniaturize the optical fiber probe (8).

Abstract: The invention is related to technical physics, in particular to devices for investigating the internal structure of objects and can be used in medicine for diagnostics of human organs and systems, in particular for optical coherence tomography and in technical diagnostics, for example technological process control. The invention relates to the creation of an optical-fiber interferometer, which, being used in a device for optical coherence tomography, allows one to investigate media with short time of changing of optical characteristics or its position relative to the optical probe, for example biotissues in vivo. The invention also relates to the creation of a piezoelectric modulator, suitable for use in the interferometer and for providing the necessary scanning depth in the mentioned media.

Abstract: The invention is related to technical physics, in particular to devices for investigating the internal structure of objects and can be used in medicine for diagnostics of human organs and systems, in particular for optical coherence tomography and in technical diagnostics, for example technological process control. The invention relates to the creation of an optical-fiber interferometer, which, being used in a device for optical coherence tomography, allows one to investigate media with short time of changing of optical characteristics or its position relative to the optical probe, for example biotissues in vivo. The invention also relates to the creation of a piezoelectric modulator, suitable for use in the interferometer and for providing the necessary scanning depth in the mentioned media.