论述了光声光谱信号的产生。提出用光纤相位传感器代替传统的微音器检测光声信号。用CO2激光器作光源对磷化氢(PH3)气体浓度进行测量。实验表明,最低检测灵敏度可达1.2×10-10。信号处理电路具有较强的抑制噪声干扰能力。该传感器及其系统在灵敏度、精度、响应时间等性能指标上达到了检测气体含量要求。

The generation of photoacoustic spectrum is presented. The optical fiber phase sensor is used to replace the traditional microphone to detect photoacoustic signal. The dye laser is used as the light source to measure PH3 gas concentration, and the sensitivity of 1.2×10-10 is obtained. The signal processing circuit has strong ability to suppress noise interference. The sensor and the system can match the requests of sensitivity, accuracy and response time in detecting gas concentration.