CAJ | 학술논문

实验中设计了一种基于微型非共振腔的石英增强光声光谱痕量气体传感器,用来检测非纯氦气中的痕量氨气浓度.该传感器采用的微型非共振腔只在空间上限制声波扩散以达到增强信号目的,而不是像传统微型共振腔一样依靠共振效应.如此的设计使探测小分子无机气体的光谱测声器尺寸远远小于共振腔的配置而有利于准直.不同气压下的信号和噪声也被研究,用来优化传感器性能.在这种配置下和27.7 kPa的最优气压下,获得的最佳氨气探测灵敏度为463 ppb (1σ,1 s积分时间),相应的归一化噪声等效吸收系数为4.3×10?9cm?1W/√Hz.
실험중설계료일충기우미형비공진강적석영증강광성광보흔량기체전감기,용래검측비순양기중적흔량안기농도.해전감기채용적미형비공진강지재공간상한제성파확산이체도증강신호목적,이불시상전통미형공진강일양의고공진효응.여차적설계사탐측소분자무궤기체적광보측성기척촌원원소우공진강적배치이유리우준직.불동기압하적신호화조성야피연구,용래우화전감기성능.재저충배치하화27.7 kPa적최우기압하,획득적최가안기탐측령민도위463 ppb (1σ,1 s적분시간),상응적귀일화조성등효흡수계수위4.3×10?9cm?1W/√Hz.
A trace gas sensor, based on quartz-enhanced photoacoustic spectroscopy (QEPAS) with two non-resonant micro-tubes, was designed to detect the ammonia concentration in impure helium. Unlike the traditional micro-resonator, the non-resonant micro-tubes are used to confine the sound wave, but do not exhibit a well-defined resonant behavior. Such a design makes the dimension of the spectrophone much smaller than the micro-resonant configuration, which facilitates the optical alignment. Signal and noise, that were dependent on gas pressure, were also investigated to optimize sensor performance. With the optimal sensor parameters and the optimal gas pressure, the detection sensitivity was found to be 463 ppb (1σ, 1 s averaging time), which corresponds to the normalized absorption sensitivity of 4.3×10?9cm?1W/√Hz.