Abstract: The present invention relates to a method of representing shape of an optical fiber sensor (12) having a central core (16) and a plurality of outer cores (14, 18, 20), each core comprising one or more sensing elements, the method comprising: (a) optically interrogating the cores (14, 16, 18, 20) of the fiber sensor (12) from an incident optical wave over a wavelength range centered on a resonance wavelength of the one or more sensing elements, wherein the wavelength range is associated with a detection limited to a minimum radius of curvature along the fiber sensor; (b) reconstructing the shape of the fiber sensor (12) involving processing of interferometric signals received from the optical interrogation of the cores (14, 16, 18, 20), including reconstructing the shape of at least one out-of-range section along the fiber sensor (12) which is a section having a radius of curvature lower than the minimum radius of curvature, wherein reconstructing the shape of the at least one out-of-range section includes cal

Abstract: The present invention relates to an optical fiber sensor, comprising an optical fiber having embedded therein at least one fiber core (14, 16, 18, 20) extending along a length of the optical fiber, the at least one fiber core having a plurality of single fiber Bragg gratings (40, 42, 44) arranged in series along the at least one fiber core (14, 16, 18, 20), wherein each fiber Bragg grating (40, 42, 44) has a single reflection spectrum around a single reflection peak wavelength when interrogated with light in an unstrained state of the at least one fiber core (14, 16, 18, 20), wherein the reflection peak wavelengths of the single reflection spectra are different from fiber Bragg grating (40, 42, 44) to fiber Bragg grating (40, 42, 44) along the at least one fiber core. Also described is an optical system and a method of interrogating an optical fiber sensor.

Abstract: The present invention relates to an optical fiber sensor, comprising an optical fiber having embedded therein at least one fiber core (14, 16, 18, 20) extending along a length of the optical fiber, the at least one fiber core having a plurality of single fiber Bragg gratings (40, 42, 44) arranged in series along the at least one fiber core (14, 16, 18, 20), wherein each fiber Bragg grating (40, 42, 44) has a single reflection spectrum around a single reflection peak wavelength when interrogated with light in an untrained state of the at least one fiber core (14, 16, 18, 20), wherein the reflection peak wavelengths of the single reflection spectra are different from fiber Bragg grating (40, 42, 44) to fiber Bragg grating (40, 42, 44) along the at least one fiber core. Also described is an optical system and a method of interrogating an optical fiber sensor.

Abstract: A medical system for minimally-invasive measurement of blood flow in an artery (AT). An interventional device (IVD) with an optical fiber (FB) comprising a plurality of temperature-sensitive optical sensor segments, e.g. Fiber Bragg Gratings, spatially distributed along its longitudinal extension is configured for insertion into an artery (AT). A temperature changer (TC) is arranged in the WD to introduce a local change in temperature (?T) of a bolus of blood in the artery, to allow thermal tracking over time with the optical fiber (FB). A measurement unit (MU) with a laser light source (LS) delivers light to the optical fiber (FB) and receives light reflected from the optical fiber (FB) and generates a corresponding time varying output signal. A first algorithm (A1) translates this time varying output signal into a set of temperatures corresponding to temperatures at respective positions along the optical fiber (FB).

Abstract: The present invention relates to an optical shape sensing system, comprising an optical fiber sensor comprising an optical fiber having embedded therein a number of at least four fiber cores (1 to 6) arranged spaced apart from a longitudinal center axis (0) of the optical fiber, the fiber cores each having a resonance wavelength in response to light introduced into the fiber cores (1 to 6) in an unstrained state thereof. The system further comprises an optical interrogation unit (21) configured to interrogate the fiber cores (1 to 6) with light in a scan wavelength range including the resonance wavelengths of the fiber cores in an unstrained state of the fiber cores (1 to 6). The scan wavelength range is set such that a center wavelength of the scan wavelength range is decentered with respect to the resonance wavelength of at least one of the fiber cores (1 to 6).

Abstract: An optical fiber (F2) having a length defining a longitudinal direction is disclosed. The optical fiber (F2) has at least two fiber cores (C21, C22) extending along the length of the optical fiber (F2), and an optical coupling member (OCM2) is arranged at a proximal optical fiber end of the optical fiber (F2). The coupling member (OCM2) has a first distal end face (OF2) optically connected to the proximal optical fiber end, and a proximal second end face (IF2) spaced apart from the first distal end face (OF2) in the longitudinal direction of the optical fiber (F2), the optical coupling member (OCM2) being configured to couple light into each of the fiber cores (C21, C22, C23).

Abstract: An optical fiber sensor includes an optical fiber. The optical fiber includes a cladding having a cladding refractive index, and a plurality of fiber cores embedded in the cladding and extending along a longitudinal axis of the optical fiber. The plurality of fiber cores include a first subset of at least one first fiber core and a second subset of at least one second fiber core. The at least one first fiber core has a first core refractive index different from the cladding refractive index and a first core radius in a direction transverse to the longitudinal axis. The at least one second fiber core has a second core refractive index different from the cladding refractive index and a second core radius transverse to the longitudinal axis. The second core refractive index and the second core radius differ from the first core refractive index and the first core radius such that a temperature sensitivity of the at least one second fiber core differs from the temperature sensitivity of the first fiber core.

Abstract: A method for end-reflection reduction of an optical shape-sensing fiber is described. The includes: providing a tip portion having a length dimension (d); connecting the tip portion to an end portion of an optical fiber configured for optical shape-sensing, the tip portion being indexed matched to the optical fiber; and adjusting the absorption properties of the tip portion using back reflections as feedback to provide an absorption length for light traveling in the optical fiber to reduce the back reflections.

Abstract: A medical interventional tool has distal and proximal ends. A responsive material is located at the distal end or elsewhere along the interventional tool and is capable of providing a temperature-dependent or pressure-dependent optical response. At least one optical guide is in optical communication with the responsive material to collect an optical signal from the responsive material located at the distal end or other location along the interventional tool. The at least one optical guide further guides the collected optical signal to an optical output at the proximal end of the interventional tool. An optical response analyzer is configured to receive the collected optical signal from the optical output and to process the collected optical signal to derive therefrom a temperature or pressure reading or indication representative of a temperature or pressure at the distal end or other location along the interventional tool.

Abstract: A reflection reduction device includes an optical fiber (104) configured for optical sensing and having an end portion. A tip portion (102) is coupled to the end portion. The tip portion includes a length dimension (d) and is index matched to the optical fiber. The tip portion is further configured to include an absorption length to absorb and scatter light within the length dimension, and a surface (S) opposite the end portion is configured to reduce back reflections.

Abstract: A medical method and system include a medical imaging system configured to generate images of an interventional procedure. An overlay generator is configured to generate an overlay image on the images of the interventional procedure. An interventional device tracking system is configured to track a three-dimensional position, orientation and shape of the interventional device during the procedure, wherein the overlay image is dynamically updated in response to deformations caused to an organ of interest by the interventional device during the procedure.

Abstract: The present invention relates to an optical shape sensing system, comprising an optical fiber sensor comprising an optical fiber having embedded therein a number of at least four fiber cores (1 to 6) arranged spaced apart from a longitudinal center axis (0) of the optical fiber, the fiber cores each having a resonance wavelength in response to light introduced into the fiber cores (1 to 6) in an unstrained state thereof. The system further comprises an optical interrogation unit (21) configured to interrogate the fiber cores (1 to 6) with light in a scan wavelength range including the resonance wavelengths of the fiber cores in an unstrained state of the fiber cores (1 to 6). The scan wavelength range is set such that a center wavelength of the scan wavelength range is decentered with respect to the resonance wavelength of at least one of the fiber cores (1 to 6).

Abstract: The present invention relates to an optical fiber sensor for shape sensing, comprising an optical fiber having embedded therein a number of at least four fiber cores (1 to 6) arranged at a distance from a longitudinal center axis (0) of the optical fiber, the number of fiber cores (1 to 6) including a first subset of at least two fiber cores (1, 3, 5) and a second subset of at least two fiber cores (2, 4, 6), the fiber cores (2, 4, 6) of the second subset being arranged to provide a redundancy in a shape sensing measurement of the fiber sensor (12?). The fiber cores (1, 3, 5) of the first subset are distributed in azimuthal direction around the center axis (0) with respect to one another, and each fiber core (2) of the second subset is arranged in non-equidistantly fashion in azimuthal direction around the center axis (0) with respect to two neighboring fiber cores (1, 3) of the first subset.

Abstract: The present invention relates to an optical fiber sensor, comprising an optical fiber having embedded therein at least one fiber core (14, 16, 18, 20) extending along a length of the optical fiber, the at least one fiber core having a plurality of single fiber Bragg gratings (40, 42, 44) arranged in series along the at least one fiber core (14, 16, 18, 20), wherein each fiber Bragg grating (40, 42, 44) has a single reflection spectrum around a single reflection peak wavelength when interrogated with light in an untrained state of the at least one fiber core (14, 16, 18, 20), wherein the reflection peak wavelengths of the single reflection spectra are different from fiber Bragg grating (40, 42, 44) to fiber Bragg grating (40, 42, 44) along the at least one fiber core. Also described is an optical system and a method of interrogating an optical fiber sensor.

Abstract: An optical apparatus (200) includes an outer jacket (230), common cladding (220), and multiple single mode fiber cores (210). The common cladding (220) is within the outer jacket (230) and is used as multimode fiber such that the outer jacket (230) clads the common cladding (220). The single mode fiber cores (210) are within the common cladding (220) such that the common cladding (220) clads the plurality of single mode fiber cores (210).

Abstract: An optical fiber sensor includes an optical fiber. The optical fiber includes a cladding having a cladding refractive index, and a plurality of fiber cores embedded in the cladding and extending along a longitudinal axis of the optical fiber. The plurality of fiber cores include a first subset of at least one first fiber core and a second subset of at least one second fiber core. The at least one first fiber core has a first core refractive index different from the cladding refractive index and a first core radius in a direction transverse to the longitudinal axis. The at least one second fiber core has a second core refractive index different from the cladding refractive index and a second core radius transverse to the longitudinal axis. The second core refractive index and the second core radius differ from the first core refractive index and the first core radius such that a temperature sensitivity of the at least one second fiber core differs from the temperature sensitivity of the first fiber core.

Abstract: A system and method for adaptive imaging include a shape sensing system (115, 117) coupled to an interventional device (102) to measure spatial characteristics of the interventional device in a subject. An image module (130) is configured to receive the spatial characteristics and generate one or more control signals in accordance with the spatial characteristics. An imaging device (110) is configured to image the subject in accordance with the control signals.

Abstract: The present invention relates to an optical shape sensor (OS), comprising an optical fiber (F2) having a length defining a longitudinal direction, the optical fiber (F2) having at least two fiber cores (C21, C22) extending along the length of the optical fiber (F2), an optical coupling member (OCM2) arranged at a proximal optical fiber end of the optical fiber (F2), the coupling member (OCM2) having a first distal end face (OF2) optically connected to the proximal optical fiber end, and a proximal second end face (IF2) spaced apart from the first distal end face (OF2) in the longitudinal direction of the optical fiber (F2), the optical coupling member (OCM2) being configured to couple light into each of the fiber cores (C21, C22, C23).

Abstract: The present invention relates to a method and system of obtaining a twist rate of a twist applied to an optical fiber (12) about a longitudinal axis of the optical fiber (12) at least in a part along a length of the optical fiber, the optical fiber (12) having a center core (16) extending along the length of the optical fiber (12) and at least one outer core (14, 18, 20) helically wound around the center core (16) with a spin rate.

Abstract: A medical method and system include a medical imaging system configured to generate images of an interventional procedure. An overlay generator is configured to generate an overlay image on the images of the interventional procedure.