Abstract: A sensor assembly having an optical fiber, a lens in optical communication with the optical fiber, a reflective surface spaced from the lens, for reflecting light from the beam back to the lens, a partially reflective surface positioned between the reflective surface and the lens, the partially reflective surface for reflecting light from the beam back to the lens, and an alignment device for aligning the lens and reflective surface with respect to one another, such that light from the beam of light transmitted from the lens reflects from the reflective surface back to the lens. The alignment device can have a rotational component and a base component, where the rotational component rotates to align a beam of light transmitted from the lens. The rotational component can also cooperate with the base component to move axially with respect to the reflective surfaces to align the beam for optimum power.

Abstract: A sensor assembly having an optical fiber, a lens in optical communication with the optical fiber, a reflective surface spaced from the lens, for reflecting light from the beam back to the lens, a partially reflective surface positioned between the reflective surface and the lens, the partially reflective surface for reflecting light from the beam back to the lens, and an alignment device for aligning the lens and reflective surface with respect to one another, such that light from the beam of light transmitted from the lens reflects from the reflective surface back to the lens. The alignment device can have a rotational component and a base component, where the rotational component rotates to align a beam of light transmitted from the lens. The rotational component can also cooperate with the base component to move axially with respect to the reflective surfaces to align the beam for optimum power.

Abstract: A method and apparatus for detecting seismic vibrations using a series of MEMS units, with each MEMS unit including an interferometer is described. The interferometers on the MEMS units receive and modulate light from two differing wavelengths by way of a multiplexing scheme involving the use of Bragg gratings and light circulators, and an optoelectronic processor receives and processes the modulated light to discern vibrational movement of the system, which in turn allows for monitoring and calculation of a specified environmental parameter, such as seismic activity, temperature or pressure.

Abstract: A method and apparatus for detecting seismic vibrations using a series of MEMS units, with each MEMS unit including an interferometer is described. The interferometers on the MEMS units receive and modulate light from two differing wavelengths by way of a multiplexing scheme involving the use of Bragg gratings and light circulators, and an optoelectronic processor receives and processes the modulated light to discern vibrational movement of the system, which in turn allows for monitoring and calculation of a specified environmental parameter, such as seismic activity, temperature or pressure.

Abstract: A fiber optic device for changing direction along a fiber optic path is provided. A first optical fiber having a first end portion, and a second optical fiber having a second end portion are joined at a fusion splice. A miniature bend is formed in the region of the fusion splice. The device is particularly useful for routing optical fibers in the field. A method of forming such a miniature bend in a fusion splice region between two optical fibers is also provided.

Abstract: An optical assembly has a miniature fiber optic bend fixedly attached to a substrate to form an integral assembly with an optical component also fixedly attached to the substrate. The assembly includes at least one optical fiber having an entering fiber portion and a return fiber portion. A miniature bend is formed in an intermediate portion that comprises an optical fiber portion between the entering fiber portion and the return fiber portion to provide a reversal of direction between the entering fiber portion and the return fiber portion. The entering fiber portion and the return fiber portion are preferably fixed in overlying relationship within a channel formed in the substrate. The resulting device is smaller, more environmentally stable, and more robust, because there is no relative motion between components. The resulting device also has fewer parts and processing steps to manufacture.

Abstract: An angled fiber optical connector which includes a curved body portion that includes an internal passageway and a treated optical fiber disposed within the internal passageway. The treated optical fiber has been annealed or otherwise treated to reduce the micromechanical stresses within the fiber in order to reduce the degradation of the optical and physical properties of the fiber. In addition, the treated portion of the optical fiber disposed within the internal passageway can be configured and arranged to prevent physical contact with any of the interior surfaces of the internal passageway.

Abstract: A fiber optic device for changing direction along a fiber optic path is provided using an asymmetrical miniature bend. The fiber optic device with the miniature bend is particularly suitable for components in which one of the fiber portions lies close to a surface, such as a single sided splitter. A method of forming such an asymmetrical miniature bend in optical fibers is also provided. In one embodiment to form the asymmetrical bend, entering and exiting fiber portions are offset along parallel axes prior to bending an intermediate portion. In another embodiment, the intermediate portion is heated at a location that is offset from a bending axis.

Abstract: A routing device for changing the direction of a fiberoptic path from a first axis to a second axis comprising a length of optical fiber having first and second directed fiber portions aligned with the first and second axes, respectively, and having a mid-potion extending through an arc of radius of the order of 2 cm or less; the mid-portion of the fiber having been treated to have a substantially reduced diameter relative to the directed fiber portions. In certain preferred embodiments, the diameter of the mid-portion of the fiber is sufficiently reduced to achieve an air-cladded state. Preferably the routing device includes an outer member for fixing the first and second directed portions relative to one another. The mid-fiber portion is preferably reduced by etching, polishing, or drawing (e.g., differential speed unidirectional drawing). Bent sections of the fiber are thermally annealed forming stress-free bends of minimum bend radius for long term applications.

Abstract: The invention features a fiber optic coupler package including a rigid substrate and at least two side-by-side optical fibers joined in a coupler region. The substrate has a coefficient of thermal expansion substantially matched to that of the fibers. Each fiber extends axially to opposite sides of the coupler region to a primary and secondary regions of fixation, at each side of the coupler region. In the primary region of fixation, each fiber is separately bonded in close proximity to a rigid mounting surface of the substrate using a small amount of adhesive contiguously disposed on opposite sides of the line of tangency formed by the fiber and the mounting surface. The adhesive is distributed to form a pair of substantially identical masses with mirror symmetry relative to a plane defined by the central fiber axis and the line of tangency.

Abstract: Bends in optical fibers can be miniaturized by reducing the diameter of a section of the fiber in the region where bending is desired to a condition in which the optical properties of the fiber have reduced bend-loss sensitivity. In one aspect of the invention, radii of curvature less than 100 microns (.mu.) and very low optical power loss are achieved. A fiber with such specially reduced diameter may also be twisted about its longitudinal axis to a greater degree than a comparable length of larger diameter fiber. Any optical fiber can be processed by redrawing and/or chemical means to allow such bending or twisting. Bend or twist tolerant regions thus formed may be packaged separately or built integrally into a wide range of fiber optic components, networks, or systems with significant space savings, added performance features and mechanical flexibility.

Abstract: An electro-optical converter has at least three optical or electrical ports at least one of which is optical and one of which is electrical. The converter includes an essentially rigid support, a fiber-optic lateral coupler secured to the support including at least two length-wise continuous optical fibers juxtaposed along a portion of their length to provide lateral transfer of optical energy therebetween, and an electro-optical device also secured to the support in close relationship to the coupler. The device has at least one optical port and at least one electrical port. One of the coupler fibers communicates within the converter with the optical port of the electro-optical device, to serve as an internal signal link therebetween. The length of the link between coupler and electro-optical device is of the order of 10 centimeters or less. Protective means associated with the optical fibers, the electro-optical device and the internal link serve to protect the components from outside physical disturbance.

Abstract: A terminator for use with an optical fiber access port structure that supports an optical fiber having an optical end face exposed to communicate with a like end face of another fiber, the terminator comprising a pig-tail-free compact supporting body carrying within itself light-absorbing means and shaped to removably interfit with the access port structure to present the light-absorbing means in light transferring relationship to the exposed end of said optical fiber at the port in manner to absorb incident light from the fiber end face and prevent back-reflection.

Abstract: An electro-optical converter has at least three optical or electrical ports at least one of which is optical and one of which is electrical. The converter includes an essentially rigid support, a fiber-optic lateral coupler secured to the support including at least two length-wise continuous optical fibers juxtaposed along a portion of their length to provide lateral transfer of optical energy therebetween, and an electro-optical device also secured to the support in close relationship to the coupler. The device has at least one optical port and at least one electrical port. One of the coupler fibers communicates within the converter with the optical port of the electro-optical device, to serve as an internal signal link therebetween. The length of the link between coupler and electro-optical device is of the order of 10 centimeters or less. Protective means associated with the optical fibers, the electro-optical device and the internal link serve to protect the components from outside physical disturbance.