Short-wave infrared super-continuum lasers for natural gas leak detection, exploration, and other active remote sensing applications

• US 9,500,634 B2
• Filed: 12/17/2013
• Issued: 11/22/2016
• Est. Priority Date: 12/31/2012
• Status: Active Grant

• Current Assignee: Omni Medsci, Inc.
• Original Assignee: Omni Medsci, Inc.
• Inventors: Islam, Mohammed N.
• Primary Examiner(s): Chowdhury, Tarifur
• Assistant Examiner(s): Rahman, Md M
• Application Number:
  US14/650,981
• Publication Number:
  US 20150316415A1
• Time in Patent Office: 1,071 Days
• Field of Search: 356/300
• US Class Current: 1/1
• CPC Class Codes: A61B 2562/0233 Special features of optical sensors or probes classified in A61B5/00
• CPC Class Codes: A61B 2562/0238 Optical sensor arrangements for performing transmission measurements on body tissue
• CPC Class Codes: A61B 2562/146 for optical coupling
• CPC Class Codes: A61B 2576/02 specially adapted for a particular organ or body part
• CPC Class Codes: A61B 5/0013 Medical image data A61B1/00011, A61B6/56, A61B8/56 take precedence
• CPC Class Codes: A61B 5/0022 Monitoring a patient using a global network, e.g. telephone networks, internet
• CPC Class Codes: A61B 5/0075 by spectroscopy, i.e. measuring spectra, e.g. Raman spectroscopy, infrared absorption spectroscopy A61B5/0071 takes precedence
• CPC Class Codes: A61B 5/0086 using infrared radiation
• CPC Class Codes: A61B 5/0088 for oral or dental tissue
• CPC Class Codes: A61B 5/14532 for measuring glucose, e.g. by tissue impedance measurement
• CPC Class Codes: A61B 5/14546 for measuring analytes not otherwise provided for, e.g. ions, cytochromes
• CPC Class Codes: A61B 5/1455 using optical sensors, e.g. spectral photometrical oximeters
• CPC Class Codes: A61B 5/4547 Evaluating teeth
• CPC Class Codes: A61B 5/6801 specially adapted to be attached to or worn on the body surface
• CPC Class Codes: A61B 5/7257 using Fourier transforms
• CPC Class Codes: A61B 5/7405 using sound
• CPC Class Codes: A61B 5/742 using visual displays A61B5/339 takes precedence
• CPC Class Codes: G01J 2003/104 Monochromatic plural sources
• CPC Class Codes: G01J 2003/1208 Prism and grating
• CPC Class Codes: G01J 2003/2826 Multispectral imaging, e.g. filter imaging
• CPC Class Codes: G01J 3/0218 : using optical fibers
• CPC Class Codes: G01J 3/108 : for measurement in the infrared range
• CPC Class Codes: G01J 3/14 : using refracting elements, e.g. prisms G01J3/18, G01J3/26 take precedence prisms per se G02B5/04
• CPC Class Codes: G01J 3/1838 : Holographic gratings
• CPC Class Codes: G01J 3/28 : Investigating the spectrum using colour filters G01J3/51
• CPC Class Codes: G01J 3/2823 : Imaging spectrometer
• CPC Class Codes: G01J 3/42 : Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry beam switching arrangements G01J3/08
• CPC Class Codes: G01J 3/453 : by correlation of the amplitudes
• CPC Class Codes: G01M 3/38 : by using light G01M3/02 takes precedence
• CPC Class Codes: G01N 2021/3595 : using FTIR
• CPC Class Codes: G01N 2021/399 : Diode laser
• CPC Class Codes: G01N 21/35 : using infrared light G01N21/39 takes precedence
• CPC Class Codes: G01N 21/3563 : for analysing solids; Preparation of samples therefor
• CPC Class Codes: G01N 21/359 : using near infrared light
• CPC Class Codes: G01N 21/39 : using tunable lasers
• CPC Class Codes: G01N 21/85 : Investigating moving fluids or granular solids
• CPC Class Codes: G01N 21/88 : Investigating the presence of flaws or contamination
• CPC Class Codes: G01N 21/9508 : Capsules; Tablets
• CPC Class Codes: G01N 2201/0221 : Portable; cableless; compact; hand-held
• CPC Class Codes: G01N 2201/061 : Sources
• CPC Class Codes: G01N 2201/06113 : Coherent sources; lasers
• CPC Class Codes: G01N 2201/062 : LED's
• CPC Class Codes: G01N 2201/08 : Optical fibres; light guides
• CPC Class Codes: G01N 2201/12 : Circuits of general importance; Signal processing
• CPC Class Codes: G01N 2201/129 : Using chemometrical methods
• CPC Class Codes: G01N 33/02 : Food
• CPC Class Codes: G01N 33/025 : Fruits or vegetables
• CPC Class Codes: G01N 33/15 : Medicinal preparations ; Physical properties thereof, e.g. dissolubility drug screening with animal cells G01N33/5008
• CPC Class Codes: G01N 33/442 : Resins, plastics
• CPC Class Codes: G01N 33/49 : Blood chemical methods for determining blood cell populations G01N33/5094; chemical analysis of blood groups or blood types G01N33/80
• CPC Class Codes: G16H 40/67 : for remote operation
• CPC Class Codes: G16Z 99/00 : Subject matter not provided for in other main groups of this subclass
• CPC Class Codes: H01S 3/0092 : Nonlinear frequency conversion, e.g. second harmonic generation [SHG] or sum- or difference-frequency generation outside the laser cavity nonlinear frequency conversion per se G02F1/35
• CPC Class Codes: H01S 3/06758 : Tandem amplifiers
• CPC Class Codes: H01S 3/302 : in an optical fibre
• CPC Class Codes: Y02A 90/10 : Information and communication technologies [ICT] supporting adaptation to climate change, e.g. for weather forecasting or climate simulation

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. 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.

Claims

1. A measurement system comprising:

a light source configured to generate an output optical beam, comprising;

one or more semiconductor sources configured to generate an input beam;

one or more optical amplifiers configured to receive at least a portion of the input beam and to deliver an intermediate beam to an output end of the one or more optical amplifiers;

one or more optical fibers configured to receive at least a portion of the intermediate beam and to deliver at least the portion of the intermediate beam to a distal end of the one or more optical fibers to form a first optical beam;

a nonlinear element configured to receive at least a portion of the first optical beam and to broaden a spectrum associated with the at least a portion of the first optical beam to at least 10 nm through a nonlinear effect in the nonlinear element to form the output optical beam with an output beam broadened spectrum; and

wherein at least a portion of the output beam broadened spectrum comprises a short-wave infrared wavelength between approximately 1400 nanometers and approximately 2500 nanometers, and wherein at least a portion of the one of more fibers is a fused silica fiber with a core diameter less than approximately 400 microns;

a measurement apparatus configured to receive a received portion of the output optical beam and to deliver a delivered portion of the output optical beam to a sample, wherein the delivered portion of the output optical beam is configured to generate a spectroscopy output beam from the sample; and

a receiver configured to receive at least a portion of the spectroscopy output beam having a bandwidth of at least 10 nanometers and to process the portion of the spectroscopy output beam to generate an output signal, and wherein the light source and the receiver are remote from the sample, and wherein the output signal is based on a chemical composition of the sample.

2. The system of claim 1, wherein the measurement apparatus is a stand-off detection apparatus, and the spectroscopy output beam is based at least in part on diffuse reflection from the sample.

3. The system of claim 1, wherein the output signal is configured for leak detection, natural gas exploration, or oil spill detection.

4. The system of claim 1, wherein the output signal corresponds to overtone or combinational bands of the chemical composition of the sample.

5. The system of claim 1, wherein the receiver comprises a detection system comprising gas filter correlation radiometry.

6. A measurement system comprising:

a light source configured to generate an output optical beam, comprising;

a plurality of semiconductor sources configured to generate an input optical beam;

a multiplexer configured to receive at least a portion of the input optical beam and to form an intermediate optical beam;

one or more fibers configured to receive at least a portion of the intermediate optical beam and to form the output optical beam;

wherein at least a portion of the one or more fibers comprises a fused silica fiber having a core diameter less than approximately 400 microns;

wherein the output optical beam comprises one or more optical wavelengths, at least a portion of which are between approximately 1400 nanometers and approximately 2500 nanometers; and

wherein the output optical beam has a broadened spectrum relative to the intermediate optical beam of at least 10 nanometers;

a measurement apparatus configured to receive a received portion of the output optical beam and to deliver a delivered portion of the output optical beam to a sample, wherein the delivered portion of the output optical beam is configured to generate a spectroscopy output beam from the sample; and

a receiver configured to receive at least a portion of the spectroscopy output beam having a bandwidth of at least 10 nanometers and to process the portion of the spectroscopy output beam to generate an output signal; and

wherein the light source and the receiver are remote from the sample, and wherein the output signal is based on a chemical composition of the sample.

7. The system of claim 6, wherein the light source comprises a super-continuum laser.

8. The system of claim 6, wherein the measurement apparatus is a stand-off detection apparatus, and the spectroscopy output beam is based at least in part on diffuse reflection from the sample.

9. The system of claim 6, wherein the output signal corresponds to overtone or combinational bands of the chemical composition of the sample.

10. The system of claim 6, wherein the output signal is configured for leak detection.

11. The system of claim 6, wherein the spectroscopy output beam comprises spectral features of hydrocarbons or organic compounds.

12. The system of claim 6, wherein the receiver comprises a wavelength tunable detection system.

13. The system of claim 6, wherein the receiver comprises a detection system comprising gas filter correlation radiometry.

14. The system of claim 6, wherein the output signal is configured for natural gas identification or oil spill identification.

15. A method of measuring, comprising:

generating an output optical beam, comprising;

generating an input optical beam from a plurality of semiconductor sources;

multiplexing at least a portion of the input optical beam and forming an intermediate optical beam; and

guiding at least a portion of the intermediate optical beam using one or more fibers including a fused silica fiber having a core diameter less than 400 microns and forming the output optical beam;

wherein the output optical beam comprises one or more optical wavelengths between 1400 nanometers and 2500 nanometers; and

broadening the spectrum of at least a portion of the intermediate optical beam to at least 10 nanometers to form the output optical beam with an output beam broadened spectrum;

receiving a received portion of the output optical beam and delivering a delivered portion of the output optical beam to a sample located remotely from the generated output optical beam;

generating a spectroscopy output beam having a bandwidth of at least 10 nanometers from the sample, wherein the spectroscopy output beam comprises spectral features of hydrocarbons or organic compounds;

receiving at least a portion of the spectroscopy output beam; and

processing the portion of the spectroscopy output beam and generating an output signal, wherein the output signal is based on a chemical composition of the sample.

16. The method of claim 15, wherein the output signal is configured for leak detection, natural gas exploration, or oil spill detection.

17. The method of claim 15, wherein the output signal corresponds to overtone or combinational bands of the chemical composition of the sample.