Cian F. Twomey , Gabriele Biagi , Albert A. Ruth , Marilena Giglio , Vincenzo Spagnolo , Liam O’Faolain , Anton J. Walsh
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引用次数: 0
Abstract
We present an all-fiber-based laser gas analyzer (LGA) employing quartz-enhanced photoacoustic spectroscopy (QEPAS) and a side-polished fiber (SPF). The LGA comprises a custom quartz tuning fork (QTF) with 0.8 mm prong spacing, two acoustic micro-resonators (mR) located on either side of the prong spacing, and a single-mode fiber containing a 17 mm polished section passing through both mRs and QTF. The SPF polished face is positioned to enable the evanescent wave (EW) to create a photoacoustic wave and excite the fundamental flexural mode of the QTF. Sensor performance was demonstrated using methane in nitrogen gas mixtures, with CH mixing ratios ranging from 75 ppmv to 1% (by volume), measured with an accumulation time of 300 ms, and a minimum detection limit of 34 ppmv subsequently determined. The EW-QEPAS sensor is ideal for miniaturization, as it does not contain any free-space optics and is suitable for gas sensing in harsh environments and where mobility is required.
PhotoacousticsPhysics and Astronomy-Atomic and Molecular Physics, and Optics
CiteScore
11.40
自引率
16.50%
发文量
96
审稿时长
53 days
期刊介绍:
The open access Photoacoustics journal (PACS) aims to publish original research and review contributions in the field of photoacoustics-optoacoustics-thermoacoustics. This field utilizes acoustical and ultrasonic phenomena excited by electromagnetic radiation for the detection, visualization, and characterization of various materials and biological tissues, including living organisms.
Recent advancements in laser technologies, ultrasound detection approaches, inverse theory, and fast reconstruction algorithms have greatly supported the rapid progress in this field. The unique contrast provided by molecular absorption in photoacoustic-optoacoustic-thermoacoustic methods has allowed for addressing unmet biological and medical needs such as pre-clinical research, clinical imaging of vasculature, tissue and disease physiology, drug efficacy, surgery guidance, and therapy monitoring.
Applications of this field encompass a wide range of medical imaging and sensing applications, including cancer, vascular diseases, brain neurophysiology, ophthalmology, and diabetes. Moreover, photoacoustics-optoacoustics-thermoacoustics is a multidisciplinary field, with contributions from chemistry and nanotechnology, where novel materials such as biodegradable nanoparticles, organic dyes, targeted agents, theranostic probes, and genetically expressed markers are being actively developed.
These advanced materials have significantly improved the signal-to-noise ratio and tissue contrast in photoacoustic methods.