Development of a Miniaturized Differential Photoacoustic Gas Sensor

Photoacoustic spectroscopy is one of the most sensitive techniques used to monitor chemical emission or to detect gas traces. However the sensors bulkiness, cost and complexity prevent their use in applications where mass deployment is required. In this paper, the development and characterization of centimeter sized photoacoustic sensors is presented. With a 2.2 mW optical power interband cascade laser at 3.36 μm wavelength, a limit of detection of 320 ppbv is obtained for methane.