Diode Laser Based Mid-IR Gas Sensors (1997 - 2000)

..................................................... Mid-infrared laser absorption spectroscopy, offers high speed, high precision, immunity to interference, and remote sensing capabilities for detection of numerous trace gas species. Tunable near-infrared diode laser sources are mixed and frequency converted to longer wavelengths using state of the art nonlinear optical crystals such as periodically poled lithium niobate. .......................................................
Prototype #1 (1996-1997):

- Diode and solid state laser pumped
- Discrete optics
- Detection of CO, H2CO and CH4

- NASA Phase II-III Lunar Mars Life
Support project: Detection of CO & H2CO

 Prototype#2 (1997):

- Diode laser pumped
- Discrete optics
- Low cost
- Detection of CH4 and H2O
   
Prototype #3 (1998-2000):

Features:
- Diode laser pumped
- Widely tunable: 3.3 - 4.4 microns
- Fiber coupled optics
- Fully automated tuning and
longterm operation
- 12 different species detected

Field tests & Applications:
- H2CO detection in a Trace Contaminant
Control System at TDA Inc., Denver, CO
- Detection of SO2, HCl, CO2, CH4, H2O
at Masaya volcano, Nicaragua		 Prototype #4 (1999-2000)

Features:
- Telecom diode laser pumped
- Fiber amplified
- Fiber coupled optics
- Longterm operation (weeks)
- shock-mounted

Field tests & Applications:
- CH4 detection in Tokyo, Japan
- Detection of CH4 and HCl at
Masaya volcano, Nicaragua
   
Prototype #5 (1999-2000):

Features:
- Telecom diode laser pumped
- High power fiber amplifiers
- Dual beam / 2f detection

Field tests & Applications:
- Sub-ppb detection of atmospheric H2CO		 Prototype #6 (1999-2000):

Features:
- Quantum Cascade Laser
- High power (mW's)
- Room temperature operation (Pulsed)

Field tests & Applications:
- Detection of CH4 and N2O