Abstract:
A system and method for using near-infrared or short-wave infrared (SWIR) light sources between approximately 1.4-1.8 microns, 2-2.5 microns, 1.4-2.4 microns, 1-1.8 microns for active remote sensing or hyper-spectral imaging for detection of natural gas leaks or exploration sense the presence of hydro-carbon gases such as methane and ethane. Most hydro-carbons (gases, liquids and solids) exhibit spectral features in the SWIR, which may also coincide with atmospheric transmission windows (e.g., approximately 1.4-1.8 microns or 2-2.5 microns). Active remote sensing or hyper-spectral imaging systems may include a fiber-based super-continuum laser and a detection system and may reside on an aircraft, vehicle, handheld, or stationary platform. Super-continuum sources may emit light in the near-infrared or SWIR s. An imaging spectrometer or a gas-filter correlation radiometer may be used to identify substances or materials such as oil spills, geology and mineralogy, vegetation, greenhouse gases, construction materials, plastics, explosives, fertilizers, paints, or drugs.
Abstract:
Die Erfindung betrifft einen Gassensor (5) zum Detektieren wenigstens einer Gaskomponente. Der Gassensor (5) umfasst einen photonischen Kristall (1), welcher eine Mehrzahl von in wenigstens eine Raumrichtung periodisch angeordneten Strukturelementen (2) aufweist. Der photonische Kristall (1) weist des Weiteren wenigstens eine Störstelle auf, durch welche wenigstens ein Resonator (12) für elektromagnetische Strahlung einer Wellenlänge gebildet ist, welche von der wenigstens einen Gaskomponente absorbierbar ist. Der Gassensor (5) umfasst einen Detektor (55), welcher als von dem photonischen Kristall (1) verschiedenes Bauelement ausgebildet und dazu ausgelegt ist, von dem wenigstens einen Resonator (12) abgegebene elektromagnetische Strahlung zu detektieren. Des Weiteren betrifft die Erfindung ein Verfahren zum Detektieren wenigstens einer Gaskomponente.
Abstract:
Gas measurement detectector configured to monitor a level of a gaseous molecular species within a flow path (18) of a flow of breathable gas that communicates with an airway of a subject is performed by infrared spectroscopy. Rather than using an individual source (20) to generate electromagnetic radiation at reference and measurement wavelengths, a near-infrared electromagnetic radiation source (22) is used to generate reference electromagnetic radiation. The detector comprising: a first source (20) configured to emit mid- infrared electromagnetic radiation; a second source (22) configured to emit near-infrared electromagnetic radiation; source optics (24) configured to combine mid-infrared and near-infrared electromagnetic radiation emitted by the first and second source into a coaxial beam, and to direct the coaxial beam across the flow path (18); sensor optics (38) configured to receive electromagnetic radiation in the coaxial beam that has traversed the flow path (18), and to divide the received electromagnetic radiation into first radiation that includes mid-infrared electromagnetic radiation and second radiation that includes near-infrared electromagnetic radiation; a first radiation sensor (40) configured to receive the first radiation, and to generate output signals conveying information related to a parameter of the mid-infrared electromagnetic radiation in the first radiation; a second radiation sensor (42) configured to receive the second radiation, and to generate output signals conveying information related to a parameter of the near-infrared electromagnetic radiation in the second radiation; and a processor (36) configured to determine a level of a gaseous molecular species within the flow of breathable gas in the flow path based on the output signals generated by the first radiation sensor (40) and the second radiation sensor (42) such that the output signals generated by the second radiation sensor (42) are implemented to compensate optical loss through the flow path. Preferably fluctuations in irradiance of the source (20) generating the electromagnetic radiation at the measurement wavelength is compensated for based on a measurement of resistance through the source (20).
Abstract:
Methods and systems for real time, in situ monitoring of fluids, and particularly the determination of both the energy content and contaminants in a gas or oil transmission facility, are provided. The system may include two separate scanning sources to scan two different, but overlapping, NIR ranges, or may involve two separate scans from a single scanning spectroscopy source. The first scan ranges from approximately 1550 nm up through 1800 nm and a second scan concurrently scans at a high resolution across a band from approximately 1560-1610 nm, the wavelength of interest for hydrogen sulfide. The second scan may provide very narrow (0.005 nm) step resolution at a higher power level over just the wavelength of interest for the contaminant. Spectroscopic optical data from the two scans, however obtained, is combined into an analytical processing module analyzes the multi-scan data to yield both energy content and contaminant quantitative data.
Abstract:
A method and analyser for identifying or verifying or otherwise characterising a sample comprising: using or having an electromagnetic radiation source for emitting electromagnetic radiation in at least one beam at a sample, the electromagnetic radiation comprising at least two different wavelengths, using or having a sample detector that detects affected electromagnetic radiation resulting from the emitted electromagnetic radiation affected by the sample and provides output representing the detected affected radiation, and using or having a processor for determining sample coefficients from the output, and identifying or verifying or otherwise characterising the sample using the sample coefficients and training coefficients determined from training samples, wherein the coefficients reduce sensitivity to a sample retainer variation and/or are independent of concentration.
Abstract:
A source assembly (48) configured to generate infrared electromagnetic radiation includes an emitter (60) that emits electromagnetic radiation over an emission solid angle. A portion of the emitted electromagnetic radiation is used in a detection. The portion of the user electromagnetic radiation surrounds the optical path in a usable solid angle. Electromagnetic radiation outside of the usable solid angle is focused back by a reflection assembly (64) onto the emitter to enhance the efficiency of the emitter.