Mid-infrared hyperspectral sensor based on MEMS Fabry-Pérot interferometer for stand-off sensing applications.

Area of Science:

• Optics and Photonics
• Materials Science
• Spectroscopy

Background:

• Hyperspectral imaging offers detailed material characterization.
• Mid-infrared spectroscopy is valuable for identifying polymers.
• Miniaturized optical components enable portable sensing solutions.

Purpose of the Study:

• To develop and demonstrate a novel hyperspectral sensor for material identification.
• To evaluate the performance of a micro-electro-mechanical system (MEMS) Fabry-Pérot interferometer coupled with a supercontinuum laser.
• To assess the sensor's capability for identifying plastics in the mid-infrared region.

Main Methods:

• Utilized a custom mid-infrared supercontinuum laser source.
• Employed a MEMS-based Fabry-Pérot interferometer for on-axis spectral filtering.
• Achieved a spectral resolution of approximately 25 nm.
• Acquired hyperspectral data at a rate of 62.5 spectra/s.

Main Results:

• Successfully demonstrated hyperspectral identification of black polypropylene (PP) and polyethylene (PE500).
• Focused on the 3-3.5 µm spectral region for plastic differentiation.
• Obtained spectral data in excellent agreement with Fourier-transform infrared (FTIR) spectroscopy.
• Confirmed that plastic coloration does not impede identification within the studied wavelength range.

Conclusions:

• The developed MEMS Fabry-Pérot based hyperspectral sensor is effective for plastic identification.
• The sensor shows robust performance across different plastic colors in the mid-infrared spectrum.
• This technology holds promise for advanced material analysis and sensing applications.