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Design and Characterization Methodology for Efficient Wide Range Tunable MEMS Filters
Published on: February 4, 2018
Frequency-agile bandpass filter for direct detection lidar receivers
Applied Optics
|February 28, 2008
Summary
A new tunable etalon receiver for carbon dioxide (CO2) laser differential absorption lidar (DIAL) systems significantly reduces detector noise. This advancement enhances the capability of DIAL systems for long-distance chemical release monitoring.
Area of Science:
- Atmospheric remote sensing
- Optical engineering
Background:
- Differential absorption lidar (DIAL) systems are crucial for atmospheric monitoring.
- Current DIAL systems face limitations in noise reduction and standoff detection capabilities.
Purpose of the Study:
- To develop a frequency-agile receiver for carbon dioxide (CO2) laser DIAL systems.
- To enhance the sensitivity and performance of DIAL systems for chemical detection.
Main Methods:
- Incorporation of a low-order tunable etalon into the detector's field of view.
- Narrowing the instantaneous spectral bandwidth of the infrared (IR) detector.
Main Results:
- Achieved a projected 2-7 reduction in detector system noise.
- Improved the overall specific detectivity (D*) of the detection system.
- Enabled a narrower wavelength range centered on the transmitted CO2 laser line.
Conclusions:
- The frequency-agile receiver design significantly reduces system noise.
- Enhanced DIAL system performance allows for improved monitoring of chemical releases.
- This technology extends the standoff detection capabilities of DIAL systems.
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