An optical gas sensing technique based on in-plane quartz-enhanced photoacoustic spectroscopy (IP-QEPAS) is reported. In IP-QEPAS, the laser beam is aligned in the plane of the quartz tuning fork (QTF) to increase the interaction area between the acoustic wavefront and the QTF. A custom T-shaped QTF with a prong length of 9.4 mm and a resonance frequency of 9.38 kHz was designed and employed in the IP-QEPAS sensor. For comparison, the traditional QEPAS sensor in which the laser beam is perpendicular to the QTF plane (PP-QEPAS) is investigated with the same operating conditions. Theoretical calculations of strain and displacement of the QTF prong were performed to support the advantage of using the IP-QEPAS technique. By selecting water vapor as the gas target, the IP-QEPAS sensor results in a signal more than 40 times higher than that measured with the PP-QEPAS configuration, confirming the potential of this approach.An optical gas sensing technique based on in-plane quartz-enhanced photoacoustic spectroscopy (IP-QEPAS) is reported. In IP-QEPAS, the laser beam is aligned in the plane of the quartz tuning fork (QTF) to increase the interaction area between the acoustic wavefront and the QTF. A custom T-shaped QTF with a prong length of 9.4 mm and a resonance frequency of 9.38 kHz was designed and employed in the IP-QEPAS sensor. For comparison, the traditional QEPAS sensor in which the laser beam is perpendicular to the QTF plane (PP-QEPAS) is investigated with the same operating conditions. Theoretical calculations of strain and displacement of the QTF prong were performed to support the advantage of using the IP-QEPAS technique. By selecting water vapor as the gas target, the IP-QEPAS sensor results in a signal more than 40 times higher than that measured with the PP-QEPAS configuration, confirming the potential of this approach.

中文翻译：

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面内石英增强光声光谱

报道了一种基于面内石英增强光声光谱 (IP-QEPAS) 的光学气体传感技术。在 IP-QEPAS 中，激光束在石英音叉 (QTF) 的平面内对齐，以增加声波前和 QTF 之间的相互作用面积。IP-QEPAS 传感器设计并采用了一个定制的 T 形 QTF，其叉长为 9.4 毫米，谐振频率为 9.38 kHz。为了进行比较，在相同的操作条件下对激光束垂直于 QTF 平面 (PP-QEPAS) 的传统 QEPAS 传感器进行了研究。对 QTF 插脚的应变和位移进行了理论计算，以支持使用 IP-QEPAS 技术的优势。通过选择水蒸气作为气体目标，IP-QEPAS 传感器产生的信号比使用 PP-QEPAS 配置测量的信号高 40 倍以上，证实了这种方法的潜力。一种基于面内石英增强光声光谱 (IP-QEPAS) 的光学气体传感技术) 报道。在 IP-QEPAS 中，激光束在石英音叉 (QTF) 的平面内对齐，以增加声波前和 QTF 之间的相互作用面积。IP-QEPAS 传感器设计并采用了一个定制的 T 形 QTF，其叉长为 9.4 毫米，谐振频率为 9.38 kHz。为了进行比较，在相同的操作条件下研究了激光束垂直于 QTF 平面 (PP-QEPAS) 的传统 QEPAS 传感器。对 QTF 插脚的应变和位移进行了理论计算，以支持使用 IP-QEPAS 技术的优势。通过选择水蒸气作为气体目标，IP-QEPAS 传感器产生的信号比使用 PP-QEPAS 配置测量的信号高 40 倍以上，证实了这种方法的潜力。