Abstract: Methods and apparatus for discrete point temperature sensing include a temperature sensor that can be part of an array of temperature sensors for location in a wellbore. A single unitary ribbon-like structure can form the temperature sensor that has separate optical cores possessing different characteristics such that one core is unique from another core. Each core has a reflective grating disposed therein such that the wavelength of light reflected by the gratings is in response to temperature and any strain applied to the sensor from a surrounding environment. For some embodiments, the responses to strain from each of the gratings are similar while the responses from each of the gratings to temperature are dissimilar due to the different characteristics of the cores. These responses provided separately by each grating therefore enable compensation for strain in order to provide an accurate temperature measurement at the sensor.

Abstract: A reclosable bag having two spaced-apart flexible closures and external finger guide ridges and/or pressure distribution ridges to facilitate their closure. The ridges lie in a region between the double closures and they extend generally parallel to each other and to the closures when the bag is in an empty and flat state. The pressure distribution ridges improve the finger pressure distribution by moving the applied forces closer to the closure profiles. When used in conjunction with external finger guide ridges, the pressure distribution ridges also improve the bearing surface of the external finger guide ridges with the thumb and forefinger of the person closing the bag.

Abstract: Methods and apparatus for discrete point temperature sensing include a temperature sensor that can be part of an array of temperature sensors for location in a wellbore. A single unitary ribbon-like structure can form the temperature sensor that has separate optical cores possessing different characteristics such that one core is unique from another core. Each core has a reflective grating disposed therein such that the wavelength of light reflected by the gratings is in response to temperature and any strain applied to the sensor from a surrounding environment. For some embodiments, the responses to strain from each of the gratings are similar while the responses from each of the gratings to temperature are dissimilar due to the different characteristics of the cores. These responses provided separately by each grating therefore enable compensation for strain in order to provide an accurate temperature measurement at the sensor.

Abstract: Methods and apparatus for discrete point temperature sensing include a temperature sensor that can be part of an array of temperature sensors for location in a wellbore. A single unitary ribbon-like structure can form the temperature sensor that has separate optical cores possessing different characteristics such that one core is unique from another core. Each core has a reflective grating disposed therein such that the wavelength of light reflected by the gratings is in response to temperature and any strain applied to the sensor from a surrounding environment. For some embodiments, the responses to strain from each of the gratings are similar while the responses from each of the gratings to temperature are dissimilar due to the different characteristics of the cores. These responses provided separately by each grating therefore enable compensation for strain in order to provide an accurate temperature measurement at the sensor.

Abstract: A reclosable bag having two spaced-apart flexible closures and external finger guide ridges and/or pressure distribution ridges to facilitate their closure. The ridges lie in a region between the double closures and they extend generally parallel to each other and to the closures when the bag is in an empty and flat state. The pressure distribution ridges improve the finger pressure distribution by moving the applied forces closer to the closure profiles. When used in conjunction with external finger guide ridges, the pressure distribution ridges also improve the bearing surface of the external finger guide ridges with the thumb and forefinger of the person closing the bag.

Abstract: Methods and apparatus for discrete point temperature sensing include a temperature sensor that can be part of an array of temperature sensors for location in a wellbore. A single unitary ribbon-like structure can form the temperature sensor that has separate optical cores possessing different characteristics such that one core is unique from another core. Each core has a reflective grating disposed therein such that the wavelength of light reflected by the gratings is in response to temperature and any strain applied to the sensor from a surrounding environment. For some embodiments, the responses to strain from each of the gratings are similar while the responses from each of the gratings to temperature are dissimilar due to the different characteristics of the cores. These responses provided separately by each grating therefore enable compensation for strain in order to provide an accurate temperature measurement at the sensor.

Abstract: The present invention provides a method for making a multicore large diameter optical waveguide having a cross-section of at least about 0.3 millimeters, two or more inner cores, a cladding surrounding the two or more inner cores, and one or more side holes for reducing the bulk modulus of compressibility and maintaining the anti-buckling strength of the large diameter optical waveguide. The method features the steps of: assembling a preform for drawing a multicore large diameter optical waveguide having a cross-section of at least about 0.3 millimeters, by providing an outer tube having a cross-section of at least about 0.3 millimeters and arranging two or more preform elements in relation to the outer tube; heating the preform; and drawing the large diameter optical waveguide from the heated preform. In one embodiment, the method also includes the step of arranging at least one inner tube inside the outer tube.

Abstract: Embodiments of the present invention provide various methods to fabricate optical fibers with reduced radiation sensitivity. Optical fibers are treated to one or more secondary or post-processing “conditioning” steps to create and anneal residual defects in the glass for improved radiation insensitivity.

Abstract: Methods to fabricate an optical preform for draw into Polarization Maintaining (PM) or Polarizing (PZ) optical fiber are provided. The methods involve assembly of pre-shaped and pieced together bulk glass elements into preforms (“assembled preforms”) for simultaneous fusing and drawing into optical fiber. These preforms form a stress-induced birefringent optical core when drawn to fiber.

Abstract: Fiber optic cables suitable for use in harsh environments such as down hole oil and gas well applications and methods for fabricating the same have been provided. In one embodiment, an optic cable suitable for down hole oil field applications comprises one or more optical fibers disposed in an inner tube and a corrosion resistant metal outer tube disposed over the inner tube, where the inner and outer tubes make intermittent contact. In another embodiment, an optic cable suitable for down hole oil field applications comprise one or more optical fibers disposed in a polymer tube having fins extending therefrom.

Abstract: A method and apparatus for terminating an end of an optical cable is disclosed such that coaxial tubes of the cable and fibers therein are all prevented from moving relative to one another. For some embodiments, the coaxial tubes crimp together by a mechanical crimp that compresses the outer tube onto the inner tube without roller crimping. A fiber retention subassembly crimps to one of the coaxial tubes, and an adhesive fills the fiber retention subassembly, thereby fixing the fibers therein and isolating tension from the ends of the fibers that extend from the fiber retention subassembly. The ends of the fibers of the optical cable connect with fibers of another optical cable or device by a fusion splice. A splice cover holds and/or seals the spliced section and prevents relative movement between the optical cables or the optical cable and the device at the spliced section.

Abstract: A fetal electrode sleeve and wire interconnect system for transmitting signals indicative of fetal heart rate from a fetus inside a mother through a cable to a monitor external to the mother. The system includes a holder having a fetal spiral electrode on one end and a maternal reference electrode on its opposite end. A safety cap has a retention groove, a grip, a tip with a recessed end opposite the grip, and a conductive sleeve. The conductive sleeve has a first end enclosed by the grip, a second end enclosed by the tip, and an intermediate exposed portion enclosed by neither the grip nor the tip.

Abstract: A fetal electrode product for transmitting signals indicative of fetal heart rate from a fetus to a monitor. The product includes a slotted introducer which can be comfortably inserted through the cervix of the mother. A drive mechanism slides and rotates a holder--to which are attached, at opposite ends, a fetal spiral electrode (FSE) and a reference electrode--within the introducer to secure the FSE to the fetus. The solid drive mechanism has a drive rod, a handle on one end of the drive rod imparting translation and rotation to the drive rod, and a clutch on the opposite end of the drive rod imparting translation and rotation to the holder. The drive rod, handle, and clutch each have a channel transporting a twisted wire strand from the electrodes to a connector. The connector has an outside dimension greater than the inner diameter of the introducer to facilitate manipulation.

Abstract: A fetal electrode product for transmitting signals indicative of fetal heart rate from a fetus to a monitor. A drive mechanism slides and rotates a holder--to which are attached, at opposite ends, a fetal spiral electrode (FSE) and a reference electrode--to secure the FSE to the fetus. The drive mechanism has a solid drive rod, with at least two regions of different diameter defining the torque versus angular deflection characteristics of the drive rods and a clutch connected to the drive rod and imparting translation and rotation to the holder. The clutch is sufficiently pliable to slip over the reference electrode when the holder resists rotation. The drive rod, a handle, and the clutch are integrally molded together to form the drive mechanism and each has a channel transporting a twisted wire strand, which includes an untwisted length to facilitate removal of the FSE from the fetus, from the electrodes to a connector.

Abstract: A packaging system for a fetal electrode assembly. The assembly includes an electrode which can be attached to a fetus. The electrode is coupled to an electrode wire. The electrode wire extends through a drive tube and terminates in a connector end. A flexible guide tube receives the drive tube. The packaging system includes a handle and a clip. The handle is attached to the rearward end of the drive tube. The handle has a forward section which detachably mounts inside the rearward end of the guide tube. The handle also has a passage for receiving the connector end and a slot for securing the electrode wire when the electrode is not in use. The electrode projects from the forward end of the guide tube when the forward section of the handle is mounted inside the rearward end of the guide tube.