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

Abstract

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−1) transmission spectrum near 3.93 μm was obtained for atmospheric observation of N2O 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.

Generation of 2.8 µm fiber laser using an Erbium‐doped ZBLAN double‐clad fiber in a linear‐cavity‐free space experimental setup

“…[1][2][3] Among those, mid-infrared (MIR) fiber laser with a range between 2 and 5 µm has been attracting great interest due to its huge potential for both fundamental research and industrial applications, ranging from telecommunications, [4][5][6] molecular detection, [7][8][9] mid-infrared supercontinuum generations, [10][11][12] material processing, [13][14][15] medical surgery to imaging, [16][17][18][19] and remote sensing. [20][21][22] MIR fiber lasers at 2.0-3.0 µm are the appropriate choices for photo dermatology and tissue ablation since biological tissue contains plenty of water, which has the strongest absorption at 2.94 µm and this is much higher compared to the absorption of CO 2 lasers at 9.6-10.6 µm. 23 The significant absorption coefficient of water in body tissue at wavelength in MIR region has positioned MIR fiber lasers as promising candidates for medical application in spectroscopy and surgery.…”

“…The fiber laser market is expected to experience substantial growth in the coming years, driven by its widespread use across various fields 1–3 . Among those, mid‐infrared (MIR) fiber laser with a range between 2 and 5 µm has been attracting great interest due to its huge potential for both fundamental research and industrial applications, ranging from telecommunications, 4–6 molecular detection, 7–9 mid‐infrared supercontinuum generations, 10–12 material processing, 13–15 medical surgery to imaging, 16–19 and remote sensing 20–22 …”

Performance Characterization of a Fully Transportable Mid-Infrared Laser Heterodyne Radiometer (LHR)

“…The atmospheric windows of 3–5 μm and 8–12 μm correspond to the strong fundamental ro-vibrational absorptions of a large number of key atmospheric species, which are more attractive for LHR-sensitive remote sensing [ 9 ]. A dual-channel LHR involving two interband cascade lasers (ICL) centered at 3.53 µm and 3.93 µm as LOs has been recently reported for remote sensing atmospheric H 2 O vapor, N 2 O, and CH 4 [ 16 , 17 , 18 ]. Weidmann et al developed an LHR based on an external cavity quantum cascade laser (EC-QCL) [ 19 ] as the LO for working in the 8.08–8.93 µm range [ 20 , 21 ], in which O 3 , N 2 O, CH 4 , CCl 2 F 2 , and H 2 O have been measured.…”

Zirconium pentatelluride saturable absorber for solid-state ultrafast lasers

“…Ultrafast solid-state lasers are widely used as light sources in laser medical treatment, scientific research and highcapacity communication [1][2][3][4][5]. As a major way to generate ultrafast lasers, passively mode-locked laser has received extensive attention due to its compactness and miniaturization.…”