基于PIN光电二极管的微型一氧化氮化学发光传感器

Miniature Chemiluminescence NO Sensor Based on PIN Photodiode

以微型、低成本的PIN光电二极管为光电探测元件,研制了微型一氧化氮化学发光传感器;选取Si探测器和InGaAs探测器的5种光电元件,考察其与一氧化氮发光光谱响应及噪声的关系。结果表明:边长为1.2mm的正方形Si探测器响应灵敏,暗电流噪声低,信噪比最低;设计的小型光腔实现了微量一氧化氮(体积分数为2×10^-6~2×10^-4)的测量,线性度为0.9993;整个系统的响应时间为0.13s,传感器的质量小于50g,非常适合用于工业污染源一氧化氮气体的在线监测。

A miniature chemiluminescence NO sensor is developed using a miniature low-cost PIN photodiode as the photoelectric detector. Five optoelectronic components of the Si detector and InGaAs detector are selected to investigate their relationship with the spectral response of NO luminescence and noise. The experimental results show that the 1.2-mm-length rectangular Si detector is the best one with the advantages of a sensitive response, a low dark-current noise, and the lowest signal-to-noise ratio. Moreover, a small optical cavity is designed, small amount of NO luminescence with a volume fraction of 2×10^-6-2×10^-4 is measured, and the linearity is 0.9993. The response time of the whole system is approximately 0.13 s and the sensor weight is less than 50 g. Thus the proposed sensor is very suitable for the online monitoring of NO gas in the industrial pollution source.