AUTHOR=Xue Zhengyue , Shen Fengjiao , Li Jun , Liu Xiaohai , Wang Guishi , Liu Kun , Gao Xiaoming , Chen Weidong , Tan Tu 

TITLE=MEMS Modulator-Based Mid-Infrared Laser Heterodyne Radiometer for Atmospheric Remote Sensing

JOURNAL=Frontiers in Physics

VOLUME=10

YEAR=2022

URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2022.945995

DOI=10.3389/fphy.2022.945995

ISSN=2296-424X

ABSTRACT=<p>The performance of a mid-infrared laser heterodyne radiometer (MIR-LHR) based on a micro-electro-mechanical system (MEMS) mirror is demonstrated in ground-based solar occultation mode. A MEMS mirror is employed as an alternative modulator to the traditional mechanical chopper. High-resolution (∼0.0024 cm<sup>−1</sup>) transmission spectrum near 3.93 μm was obtained for atmospheric observation of N<sub>2</sub>O absorption. Operation of the MIR-LHR with laser-induced shot-noise limited performance was analyzed and experimentally achieved. The laser heterodyne spectrum obtained is consistent with Fourier-transform infrared (FT-IR) spectrometer and atmospheric transmission modeling. Compared to the traditional chopper, the MEMS mirror is smaller, lighter and lower power consumption which makes the system more stable and compact. The reported MIR-LHR in this article has great potential in aircraft instruments and satellite payloads.</p>