Patent application number | Description | Published |
20100150497 | EVANESCENT SENSOR USING A HOLLOW-CORE RING MODE WAVEGUIDE - Method and apparatus enable optical evanescent sensing utilizing a waveguide with an annular core. The annular core can provide detectable sensitivity to a measurand due to optical interactions with contents along an inside surface of the annular core since optical properties of the contents vary with changes in the measurand. | 06-17-2010 |
20120111104 | FIBER OPTIC CABLE FOR DISTRIBUTED ACOUSTIC SENSING WITH INCREASED ACOUSTIC SENSITIVITY - Methods and apparatus for performing Distributed Acoustic Sensing (DAS) using fiber optics with increased acoustic sensitivity are provided. Acoustic sensing of a wellbore, pipeline, or other conduit/tube based on DAS may have increased acoustic sensitivity through fiber optic cable design and/or increasing the Rayleigh backscatter property of a fiber's optical core. Some embodiments may utilize a resonant sensor mechanism with a high Q coupled to the DAS device for increased acoustic sensitivity. | 05-10-2012 |
20140245588 | ARRAY TEMPERATURE SENSING METHOD AND SYSTEM - Methods and apparatus enable monitoring conditions in a well-bore using multiple cane-based sensors. The apparatus includes an array of cane-based Bragg grating sensors located in a single conduit for use in the well-bore. For some embodiments, each sensor is located at a different linear location along the conduit allowing for increased monitoring locations along the conduit. | 09-04-2014 |
20140339411 | OPTICAL COUPLERS USED IN A DOWNHOLE SPLITTER ASSEMBLY - Techniques and apparatus are provided for downhole sensing using optical couplers in a downhole splitter assembly to split interrogating light signals into multiple optical sensing branches. Each optical branch may then be coupled to an optical sensor (e.g., a pass-through or an optical single-ended transducer (OSET)) or to another optical coupler for additional branching. The sensors may be pressure/temperature (P/T) type transducers. Some systems may exclusively use OSETs as the optical sensors. In this manner, if one of the OSETs is damaged, it does not affect light traveling to any of the other sensors, and sensing information from remaining sensors is still returned. | 11-20-2014 |
20140340235 | TIME DIVISION MULTIPLEXING (TDM) AND WAVELENGTH DIVISION MULTIPLEXING (WDM) FAST-SWEEP INTERROGATOR - Methods and apparatus for fast sweeping a spectral bandwidth in order to distinguish among signals received from effectively wavelength division multiplexed (WDMed) and time division multiplexed (TDMed) optical components on a single fiber. For some embodiments, a method for interrogating optical elements having characteristic wavelengths spanning a sweep range is provided. The method generally includes introducing a pulse of light, by an optical source, into an optical waveguide to interrogate at least a first set of optical elements having different characteristic wavelengths by performing a sweep of wavelengths over a period of the pulse, wherein the period is less than a round-trip time for light reflected from an optical element closest to the optical source to reach a receiver and processing the reflected light to determine a parameter based on the times at which signals are received. | 11-20-2014 |
Patent application number | Description | Published |
20090290160 | WAVELENGTH SWEEP CONTROL - Methods and apparatus for the active control of a wavelength-swept light source used to interrogate optical elements having characteristic wavelengths distributed across a wavelength range are provided. | 11-26-2009 |
20100128348 | WAVELENGTH SWEEP CONTROL - Methods and apparatus for the active control of a wavelength-swept light source used to interrogate optical elements having characteristic wavelengths distributed across a wavelength range are provided. | 05-27-2010 |
20130098528 | METHODS AND APPARATUS FOR CONTROLLING EXCESS FIBER LENGTH (EFL) IN ARMORED CABLE - Certain aspects of the present disclosure provide techniques and corresponding apparatus for making armored cables with optical fibers contained therein. The techniques may be utilized to control an amount of excess fiber length (EFL) in the armored cables. The techniques may also allow introduction of optical fibers directly into a welding process without using an inner tube in the final armored cable. | 04-25-2013 |
20130148190 | WAVELENGTH SWEEP CONTROL - Methods and apparatus for the active control of a wavelength-swept light source used to interrogate optical elements having characteristic wavelengths distributed across a wavelength range are provided. | 06-13-2013 |
20140341501 | TIME DELAY COMPENSATION FOR OPTICAL WAVEGUIDES USING A BIDIRECTIONAL WAVELENGTH SCAN - Methods and apparatus for accurately determining wavelength by compensating a time delay using a bidirectional wavelength scan are provided. One example method generally includes introducing first wavelength-swept light into an optical waveguide according to a first sweep function having a first wavelength sweep direction; interrogating one or more optical elements, having characteristic wavelengths, with the first wavelength-swept light to produce a first set of optical signals, wherein the optical elements are disposed along the optical waveguide; introducing second wavelength-swept light into the optical waveguide according to a second sweep function having a second wavelength sweep direction, wherein the second wavelength sweep direction is opposite the first wavelength sweep direction; interrogating the optical elements with the second wavelength-swept light to produce a second set of optical signals; and determining a parameter associated with at least one of the optical elements based on the first and second sets of optical signals. | 11-20-2014 |