In this paper, a novel single fiber-type double cavity enhanced photoacoustic spectroscopy (SFDCE-PAS) sensor has been proposed and demonstrated for trace methane (CH <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> ) sensing. The mainly consists of Fabry-Perot (F-P) chamber, fiber-optic ceramic pin, polyethylene terephthalate (PET) film, (PA) cavity. PET film acts as an acoustic sensing unit the excitation light can transmit into PA...

This paper reports a mini-resonant photoacoustic sensor for high-sensitivity trace gas sensing. The primarily contains sphere-cylinder coupled acoustic resonator, cylindrical buffer chamber, and fiber-optic sensor. field distributions of this the conventional T-type resonant have been carefully evaluated, showing that first-order resonance frequency present is reduced by nearly half compared to volume developed cavity only about 0.8 cm

We report, what we believe to be, a novel miniaturized 3D-printed Y-type resonant photoacoustic cell (YRPAC) consisting of frustum cone-type buffer chamber and cylindrical chamber. The volume the designed YRPAC is about 7.0 cm3, which only half T-resonant (TRPAC). finite element simulation sound field distribution TRPAC based on COMSOL shows that signal enhanced with shape changing from traditional cylinder cone. spectroscopy (PAS) system, utilizing as reaction units, 1653.7 nm distributed...

This paper presents an all-optical high-sensitivity resonant photoacoustic (PA) sensor to realize remote, long-distance and space-limited trace gas detection. The is integration of a T-type PA cell particular cantilever-based fiber-optic acoustic sensor. finite element simulations about the cantilever vibration mode field distributions are carried out based on COMSOL. sensor, together with high-speed spectrometer DFB laser source, makes up spectroscopy (PAS) system which employed for CH 4...

We propose an all-optical miniaturized multigas simultaneous detection photoacoustic (PA) sensor, which is primarily composed of a copper tube, silica cantilever, and four single-mode fibers. Three fibers are used as excitation to transmit lasers different wavelengths, the remaining one probe fiber. The volumes PA cell (PAC) sensor 36 μL 71 cubic millimeters, respectively. A laser spectroscopy (PAS) system, using detector, 1532.8, 1576.3, 1653.7 nm distributed feedback (DFB) sources for...

Abstract We propose a novel high‐performance dual‐resonance enhanced photoacoustic spectroscopy (DRE‐PAS) gas sensor based on highly sensitive fiber optic cantilever beam microphone and high‐Q spherical cell (PAC). The first‐order resonant frequency (FORF) of the PAC is analyzed by finite element analysis to match FORF for double resonance enhancement signal. (PAS) system, including DRE‐PAS sensor, 1532.8 nm distributed feedback laser, high‐speed spectrometer, has been successfully exploited...

In this paper, a fiber-tip all-optical photoacoustic (PA) transducer is demonstrated. The integrated by silicon cantilever, single optical fiber and dioxide tube. excitation light source of the PA signals detecting Fabry-Perot (F-P) fiber-optic acoustic are coupled in through wavelength division multiplexer. tube has truncated cone-shaped cavity, which serves both as F-P cavity cell. Due to special structure, volume cell ∼ 1.1 μL overall 17 cubic millimeters. miniaturized transducer,...

Conventional cantilever-enhanced photoacoustic spectroscopy (CEPAS) usually requires the cantilever to be in contact with gas, which limits its application dusty and corrosive gas sensing. To overcome this challenge, paper proposes noncontact fiber-optic (NCFO-CEPAS) for high-sensitivity trace analysis. A polyethylene film corrosion-resistant properties is affixed end of acoustic sensor, effect distance between sensor on sensitivity system analyzed by finite element Compared conventional...

A silicon cantilever-based fiber-optic acoustic sensor (FOAS) is presented in this work. rectangular cantilever fabricated upon a silicon-on-insulator (SOI) wafer using micro-electro-mechanical system (MEMS). The length, width and thickness of the are 530 μm, 200 μm 3 respectively. resonant frequency 14820 Hz with sensitivity 950 nm/Pa. An ultra-high speed absolute cavity length demodulation method adopted complementary metal oxide semiconductor (CMOS) spectrometer an 850 nm superluminescent...

An ultra-high-sensitivity, miniaturized Fabry-Perot interferometric (FPI) fiber-optic microphone (FOM) has been developed, utilizing a silicon cantilever as an acoustic transducer. The volumes of the cavity and FOM are determined to be 60 microliters 102 cubic millimeters, respectively. pressure sensitivities 1506 nm/Pa at 2500 Hz 26,773 3233 Hz. minimum detectable (MDP) signal-to-noise ratio (SNR) designed 0.93 μPa/Hz1/2 70.14 dB, respectively, 0.003 Pa. characteristics ultra-high...

In photoacoustic spectroscopy based multicomponent gas analysis, the overlap of absorption spectra among different gases can affect measurement accuracy concentrations. We report a analysis method on empirical modal decomposition (EMD), convolutional neural networks (CNN), and long short-term memory (LSTM) that extract exact concentrations mixed from overlapping wavelength-modulated with second harmonic (WMS-2f) detection. The WMS-2f signals 25 concentration combinations acetylene-ammonia...

Abstract In this paper, a scattering enhanced photoacoustic spectroscopy (SEPAS) technique is introduced for trace gas detection. An acetate membrane mounted at the inner wall of miniaturized (PA) cell to improve light‐gas interaction path. It has been found out from theoretical simulations that light rays in PA with material are obviously denser, leading large enhancement signal. A SEPAS system, mainly consisting sensor, near‐infrared distributed feedback laser source, and high‐speed...

ABSTRACT This paper presents a miniature Rollar‐type resonant photoacoustic cell (RRPAC), consisting of two cylindrical cavities and buffer chamber. The finite element analysis the acoustic field distributions for RRPAC T‐type (TRPAC) is utilized, demonstrating that can produce greater signal than conventional TRPAC. A high sensitivity trace C 2 H spectroscopy (PAS) system successfully developed by combining cantilever beam‐based sensor as sensing unit high‐speed spectrometer demodulation...

In this paper, a new scattering enhanced photoacoustic (PA) spectroscopy (SEPAS) technique is introduced for trace gas detection. The porous materials are used to improve the absorption optical length of gas. working mechanism signal in explained by simulation analysis. Through analysis, enhancement material explained, and experimental results objectively prove that SEPAS can achieve at least three times PA signal. proposed paper increase amplitude sensitivity

In this paper, a miniature all-optical dual-resonance photoacoustic (PA) sensor is demonstrated. This consists of small size resonant T-type PA cell together with an integrated probe silicon cantilever beam. With the average time 1 s, minimum detection limit tested to be 1.2 parts-per-million. Therefore, we believe that reported can suitable for high-sensitivity measurements trace gases in sub-cubic centimeter-scale spaces.