Abstract
Abstract
A laser resonant photoacoustic (PA) spectrometer has been designed for methane detection. The design ideas and methods of the device are discussed in detail. Relevant tests are designed and done for testing and verifying the important parameters of the device. The experimental results show that the radiation wavelength of the distributed feedback (DFB) diode laser increases approximately linearly with the increase of operating temperature or injection current, and the change gradient of radiation wavelength to operating temperature is greater than that to injection current. Under the condition of low gas concentration and low laser power, the relationship between PA signal, laser power and methane concentration is linear.