Fiber optic coupled multipass gas minicell, design assembly thereof

Patent metadata

Field	Value
Publication number	US-9234794-B2
Application number	US-201414311616-A
Country	US
Kind code	B2
Filing date	Jun 23, 2014
Priority date	Jun 25, 2013
Publication date	Jan 12, 2016
Grant date	Jan 12, 2016

Abstract

A method directs a gas of interest into a minicell and uses an emitting laser to produce laser emission light that is directed into the minicell and onto the gas of interest. The laser emission light is reflected within the cell to make multipasses through the gas of interest. After the multipasses through the gas of interest the laser light is analyzed to produces gas spectroscopy data. The minicell receives the gas of interest and a transmitting optic connected to the minicell that directs a beam into the minicell and onto the gas of interest. A receiving optic connected to the minicell receives the beam from the gas of interest and directs the beam to an analyzer that produces gas spectroscopy data.

First claim

The invention claimed is:

1. An apparatus for gas spectroscopy of a gas of interest, comprising:
a gas cell, said gas cell including
a first side,
a second side, and
an interior,
wherein said second side is opposed to said first side and wherein said interior is between said first side and said second side,
a first side mirror positioned in said interior adjacent said first side,
a second side mirror positioned in said interior adjacent said second side,
wherein said second side mirror is opposed to said first side mirror with said interior between said first side mirror and said second side mirror,
a gas containment system for introducing the gas of interest into said interior of said gas cell between said first side mirror and said second side mirror,
a light source that produces a light beam,
a transmitting optical fiber connected to said gas cell that receives said light beam from said light source and directs said light beam into said interior of said gas cell between said first side mirror and said second side mirror and onto the gas of interest in said interior of said gas cell between said first side mirror and said second side mirror,
wherein said first side mirror and said second side mirror are positioned relative to each other so that said light beam is reflected between said first side mirror and said second side mirror through the gas of interest in said interior of said gas cell,
a receiving optical fiber connected to said gas cell, said optical fiber positioned relative to said first side mirror and said second side mirror so that said optical fiber receives said light beam from the gas of interest in said interior of said gas cell and provides an exit light beam; and
a gas spectroscopy analyzer connected to said receiving optical fiber that receives said exit light beam and produces gas spectroscopy data.

2. The apparatus for gas spectroscopy of a gas of interest of claim 1 wherein said first side mirror and said second side mirror in said interior of said gas cell are arranged to reflect said light beam from said first side mirror to said second side mirror so that said light beam makes a multiplicity of different passes through said gas of interest in said interior of said gas cell and wherein said first side mirror has an inclination that steers said light beam to completely fill said second side mirror so that said light beam makes a multiplicity of different passes through said gas of interest in said interior of said gas cell.

3. The apparatus for gas spectroscopy of a gas of interest of claim 1 wherein said first side mirror and said second side mirror are arranged to reflect said light beam from said first side mirror to said second side mirror so that said light beam makes a multiplicity of different passes through said gas of interest in said interior of said gas cell and wherein said first side mirror has an inclination that steers said light beam to completely fill said second side mirror so that said light beam makes a multiplicity of sixty-four different passes through the gas of interest.

4. The apparatus for gas spectroscopy of a gas of interest of claim 1 wherein said gas containment system includes an inlet into said gas cell and a conduit for directing the gas of interest into said gas cell.

5. The apparatus for gas spectroscopy of a gas of interest of claim 1 wherein said gas cell is a minicell having dimensions of four centimeters by five centimeters by one centimeter or less.

6. The apparatus for gas spectroscopy of a gas of interest of claim 1 wherein said first side mirror has a notch that direct said light beam to said receiving optical fiber.

7. The apparatus for gas spectroscopy of a gas of interest of claim 1 wherein said light source is a laser light source that produces said light beam.

8. The apparatus for gas spectroscopy of a gas of interest of claim 7 wherein said laser light source is a tunable laser.

9. The apparatus for gas spectroscopy of a gas of interest of claim 7 wherein said laser light source is a tunable diode laser.

10. The apparatus for gas spectroscopy of a gas of interest of claim 7 wherein said laser light source is a multiplicity of individual lasers.

11. The apparatus for gas spectroscopy of a gas of interest of claim 7 wherein said laser light source is a tunable vertical cavity surface emitting laser for multiplexing by providing laser light with wavelengths for multiple gases of interest.

12. The apparatus for gas spectroscopy of a gas of interest of claim 1 further comprising additional gas cells wherein each gas cell includes a transmitting and receiving unit for sending and receiving data signals and a computer and data storage unit with an antenna for receiving unit for sending and receiving data signals.

13. An apparatus for gas spectroscopy of a gas of interest, comprising:
a gas minicell, said gas minicell including
a first side,
a second side, and
an interior,
wherein said second side is opposed to said first side and wherein said interior is between said first side and said second side,
two first side mirrors positioned in said interior adjacent said first side,
a second side mirror positioned in said interior adjacent said second side wherein said second side mirror is opposed to said two first side mirrors with said interior between said two first side mirrors and said second side mirror,
a gas containment system for introducing the gas of interest into said interior,
a light source that produces a light beam,
a transmitting optical fiber or fibers connected to said gas minicell that receives said light beam from said light source and directs said light beam into said interior and onto the gas of interest in said interior,
a receiving optical fiber or fibers connected to said gas minicell that receives said light beam from said gas of interest in said interior and directs said light beam from the gas of interest in said interior;
wherein said two first side mirrors have inclinations that direct said light beam to said second side mirror and wherein said inclinations are offset to steer said light beam to completely fill said second side mirror and
wherein said two first side mirrors and said second side mirror are positioned relative to each other and relative to said transmitting optical fiber or fibers and said receiving optical fiber or fibers that said light beam makes a multiplicity of different passes through said gas of interest in said interior, and
a gas spectroscopy analyzer connected to said receiving optical fiber or fibers that receives said light beam from said receiving optical fiber or fibers and produces gas spectroscopy data.

14. The apparatus for gas spectroscopy of a gas of interest of claim 13 wherein said second side mirror has a notch that direct said light beam to said receiving optical fiber or fibers.

15. The apparatus for gas spectroscopy of a gas of interest of claim 13 wherein said two first side mirrors and said second side mirror are arranged to reflect said light beam so that said light beam makes a multiplicity of twenty seven different passes through the gas of interest in said interior.

16. The apparatus for gas spectroscopy of a gas of interest of claim 13 wherein said laser light source is a laser light source.

17. The apparatus for gas spectroscopy of a gas of interest of claim 16 wherein said laser light source is a tunable diode laser.

18. The apparatus for gas spectroscopy of a gas of interest of claim 16 wherein said laser light source is a multiplicity of individual lasers.

Assignees

• L Livermore Nat Security Llc

Inventors

• Bond Tiziana C
• Bora Mihail
• Engel Michael A
• Mccarrick James F
• Moran Bryan D

Classifications

• G01J3/0218 Primary

  using optical fibers · CPC title

• G01J3/42

  Absorption spectrometry; Double beam spectrometry; Flicker spectrometry; Reflection spectrometry (beam switching arrangements G01J3/08) · CPC title

• G01J2003/421

  Single beam · CPC title

• G01N21/03

  Cuvette constructions · CPC title

• G01J3/10

  Arrangements of light sources specially adapted for spectrometry or colorimetry · CPC title