Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A thermal protection system (TPS) test plug has optical fibers with FBGs embedded in the optical fiber arranged in a helix, an axial fiber, and a combination of the two. Optionally, one of the optical fibers is a sapphire FBG for measurement of the highest temperatures in the TPS plug. The test plug may include an ablating surface and a non-ablating surface, with an engagement surface with threads formed, the threads having a groove for placement of the optical fiber. The test plug may also include an optical connector positioned at the non-ablating surface for protection of the optical fiber during insertion and removal.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A sensor for force is formed from an elastomeric cylinder having a region with apertures. The apertures have passageways formed between them, and an optical fiber is introduced into these passageways, where the optical fiber has a grating for measurement of tension positioned in the passageways between apertures. Optionally, a temperature measurement sensor is placed in or around the elastomer for temperature correction, and if required, a copper film may be deposited in the elastomer for reduced sensitivity to spot temperature variations in the elastomer near the sensors.

Abstract: A sensor for force is formed from an elastomeric cylinder having a region with apertures. The apertures have passageways formed between them, and an optical fiber is introduced into these passageways, where the optical fiber has a grating for measurement of tension positioned in the passageways between apertures. Optionally, a temperature measurement sensor is placed in or around the elastomer for temperature correction, and if required, a copper film may be deposited in the elastomer for reduced sensitivity to spot temperature variations in the elastomer near the sensors.

Abstract: A fiber optic sensor comprises two independent fibers having Bragg gratings which are coupled to commutating broadband optical sources through splitters and wavelength discriminators. The ratio of detected optical energy in each of two detectors examining the wave intensity returned to a wavelength discriminator coupled with the characteristic of the wavelength discriminator determines the wavelength returned by the grating. In another embodiment, tunable filters are utilized to detect minimum returned wave energy to extract a sensor wavelength Reference to the original grating wavelength indicates the application of either temperature or strain to the grating. In another embodiment, a plurality of Bragg grating sensor elements is coupled to sources and controllers wherein a dimensional change in a fiber having a Bragg grating is detected using a measurement system comprising broad-band sources, optical power splitters, a high-sensitivity wavelength discriminator, optical detectors, and a controller.

Abstract: A fiber optic sensor comprises two independent fibers having Bragg gratings which are coupled to commutating broadband optical sources through splitters and wavelength discriminators. The ratio of detected optical energy in each of two detectors examining the wave intensity returned to a wavelength discriminator coupled with the characteristic of the wavelength discriminator determines the wavelength returned by the grating. In another embodiment, tunable filters are utilized to detect minimum returned wave energy to extract a sensor wavelength Reference to the original grating wavelength indicates the application of either temperature or strain to the grating. In another embodiment, a plurality of Bragg grating sensor elements is coupled to sources and controllers wherein a dimensional change in a fiber having a Bragg grating is detected using a measurement system comprising broad-band sources, optical power splitters, a high-sensitivity wavelength discriminator, optical detectors, and a controller.

Abstract: A fiber optic sensor comprises two independent fibers having Bragg gratings which are coupled to commutating broadband optical sources through splitters and wavelength discriminators. The ratio of detected optical energy in each of two detectors examining the wave intensity returned to a wavelength discriminator coupled with the characteristic of the wavelength discriminator determines the wavelength returned by the grating. In another embodiment, tunable filters are utilized to detect minimum returned wave energy to extract a sensor wavelength Reference to the original grating wavelength indicates the application of either temperature or strain to the grating. In another embodiment, a plurality of Bragg grating sensor elements is coupled to sources and controllers wherein a dimensional change in a fiber having a Bragg grating is detected using a measurement system comprising broad-band sources, optical power splitters, a high-sensitivity wavelength discriminator, optical detectors, and a controller.

Abstract: A fiber optic sensor comprises two independent fibers having Bragg gratings which are coupled to commutating broadband optical sources through splitters and wavelength discriminators. The ratio of detected optical energy in each of two detectors examining the wave intensity returned to a wavelength discriminator coupled with the characteristic of the wavelength discriminator determines the wavelength returned by the grating. In another embodiment, tunable filters are utilized to detect minimum returned wave energy to extract a sensor wavelength Reference to the original grating wavelength indicates the application of either temperature or strain to the grating. In another embodiment, a plurality of Bragg grating sensor elements is coupled to sources and controllers wherein a dimensional change in a fiber having a Bragg grating is detected using a measurement system comprising broad-band sources, optical power splitters, a high-sensitivity wavelength discriminator, optical detectors, and a controller.

Abstract: A fiber optic sensor comprises two independent fibers having Bragg gratings which are coupled to commutating broadband optical sources through splitters and wavelength discriminators. The ratio of detected optical energy in each of two detectors examining the wave intensity returned to a wavelength discriminator coupled with the characteristic of the wavelength discriminator determines the wavelength returned by the grating. In another embodiment, tunable filters are utilized to detect minimum returned wave energy to extract a sensor wavelength. Reference to the original grating wavelength indicates the application of either temperature or strain to the grating. In another embodiment, a plurality of Bragg grating sensor elements is coupled to sources and controllers wherein a dimensional change in a fiber having a Bragg grating is detected using a measurement system comprising broad-band sources, optical power splitters, a high-sensitivity wavelength discriminator, optical detectors, and a controller.

Abstract: New elements mode-converting two-mode grating and mode-filtering two-mode coupler are disclosed and used as elements in a system for communications, add-drop filtering, and strain sensing. Methods of fabrication for these new two-mode gratings and mode-filtering two-mode couplers are also disclosed.

Abstract: A tunable filter comprises either an internal or an external grating proximal to a variable index of refraction material. This variable index of refraction material may vary upon the application of an external electrical potential or the application of a change in temperature of the polymer. Additionally, the grating may comprise a periodic modulation of the index of refraction, this periodic modulation comprising an isoplanar modulation of the index of refraction at an angle to the central axis of the waveguide, thereby causing conversion of fundamental mode waves to second mode waves, and by reciprocity, conversion of second mode waves to fundamental mode waves.

Abstract: New elements mode-converting two-mode grating and mode-filtering two-mode coupler are disclosed and used as elements in a system for communications, add-drop filtering, and strain sensing. Methods of fabrication for these new two-mode gratings and mode-filtering two-mode couplers are also disclosed.

Abstract: A tapered optical fiber component is provided that has an optical fiber with a cladded region. An optical core passes through the cladded region. The cladded region has a tapered extended first region drawn down in diameter to form an effective area region that has a predetermined effective area. The tapered extended first region is formed to adiabatically concentrate an optical signal for propagation through the effective area region of reduced diameter. The power density of the optical signal propagating through the effective area region is increased as an inverse function of the effective area.