Multi-Wavelength QCL Based MIR Spectroscopy for Fluids and Gases

Jouy, Pierre; Bonetti, Yargo; Hans, Kerstin M.-C.; Gianella, Michele; Sigrist, Markus; Mangold, Markus; Tuzson, Béla; Emmenegger, Lukas; Wägli, Philip; Homsy, Alexandra; Chang, Yu‐Chi; Francesco, J. di; Hvozdara, L.; Herzig, Hans Peter; Looser, Herbert; Hofstetter, Daniel; Faist, Jérôme

doi:10.1364/cleo_at.2013.jm4k.1

Cited by 2 publications

(3 citation statements)

References 6 publications

(5 reference statements)

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Another approach to speed data collection is to employ multiplexing. − Current QCL imaging systems do not address the loss of spectral multiplexing inherently advantageous when using FT systems. Despite modern configurations commonly consisting of four individual QCL lasers per microscope to span the fingerprint region, only one laser is transmitted at a time.…”

Section: Results and Discussionmentioning

confidence: 99%

Multicolor Discrete Frequency Infrared Spectroscopic Imaging

2019

View full text Add to dashboard Cite

Advancement of discrete frequency infrared (DFIR) spectroscopic microscopes in image quality and data throughput are critical to their use for analytical measurements. Here, we report the development and characterization of a point scanning instrument with minimal aberrations and capable of diffraction-limited performance across all fingerprint region wavelengths over arbitrarily large samples. The performance of this system is compared to commercial state of the art Fourier transform infrared (FT-IR) imaging systems. We show that for large samples or smaller set of discrete frequencies, point scanning far exceeds (~10-100 fold) comparable data acquired with FT-IR instruments. Further we show improvements in image quality using refractive lenses that show significantly improved contrast across the spatial frequency bandwidth. Finally, we introduce the ability to image two tunable frequencies simultaneously using a single detector by means of demodulation to further speed up data acquisition and reduce the impact of scattering. Together, the advancements provide significantly better spectral quality and spatial fidelity than current state of the art imaging systems while promising to make spectral scanning even faster.

show abstract

Section: Results and Discussionmentioning

confidence: 99%

Multicolor Discrete Frequency Infrared Spectroscopic Imaging

2019

View full text Add to dashboard Cite

show abstract

“…The application of such schemes spans from health to security, from imaging to environmental monitoring [50,51,52,53,54,55].…”

Section: Optical Monitoring Of Dioxins and Related Compounds A Scmentioning

confidence: 99%

Dioxin and Related Compound Detection: Perspectives for Optical Monitoring

Patrizi

Cumis

Viciani

et al. 2019

IJMS

View full text Add to dashboard Cite

Dioxins and related compounds are environmental xenobiotics that are dangerous to human life, due to the accumulation and persistence in the environment and in the food chain. Cancer, reproductive and developmental issues, and damage to the immune system and endocrine system are only a few examples of the impact of such substances in everyday life. For these reasons, it is fundamental to detect and monitor these molecules in biological samples. The consolidated technique for analytical evaluation is gas chromatography combined with high-resolution mass spectrometry. Nowadays, the development of mid-infrared optical components like broadband laser sources, optical frequency combs, high performance Fourier-transform infrared spectroscopy, and plasmonic sensors open the way to new techniques for detection and real time monitoring of these organic pollutants in gaseous or liquid phase, with sufficient sensitivity and selectivity, and in short time periods. In this review, we report the latest techniques for the detection of dioxins, furans and related compounds based on optical and spectroscopic methods, looking at future perspectives.

show abstract

“…Typically, it is not possible to address the spectra of different gases with a single laser. Here, we explore the concept of "multi-color" spectroscopy based on a dual-wavelength QCL [8]. The active region of the laser consists of two different active layers stacked on top of each other, optimized for a broadband emission at 1600 cm -1 and 1900 cm -1 , while single-mode emission at the desired wavelengths is ensured by a succession of two 978-1-55752-968-8/15/$31.00 ©2015 Optical Society of America distributed-feedback (DFB) gratings with different periodicities.…”

Section: Multi-species Detectionmentioning

confidence: 99%